Proceedings 28th Symposium ESVN‐ECVN Amsterdam, The Netherlands 18th–19th September 2015

TIMETABLE OF THE SYMPOSIUM

FRIDAY 18 TH SEPTEMBER
08.00:	Registration
	MOVEMENT DISORDERS
08.30:	Welcome to the meeting
08.40:	INVITED SPEAKER SESSION
	Hans Stroink
	“EPILEPSY IN CHILDREN, CLASSIFICATION AND DIAGNOSTICS, WHEN IS IT EPILEPSY?”
09.30:	FREE COMMUNICATIONS RESEARCH ABSTRACTS
	1) EPILEPTOID CRAMPING SYNDROME IN THE NORWICH TERRIER: CLINICAL CHARACTERISATION AND PREVALENCE IN THE UK
	L De Risio, J Freeman
	2) DEGENERATIVE ENCEPHALOPATHY OF NOVA SCOTIA DUCK TOLLING RETRIEVERS
	E Barker, D O'Brien, L Dawson, G Johnson, J Rose, S Van Meervenne, K Sörensen, C Rohdin, A Leijon, O Frykman, N Granger
	3) EPILEPTOGENIC ELECTROENCEPHALOGRAPHIC FINDINGS IN CANINE EPISODIC HEAD TREMOR SYNDROME
	FMK James, S Dugas, MA Cortez, S Sanders, L Barnard, G Leblond, T Jokinen, H Lohi
10.15:	Coffee break, poster exhibition and sponsors
	4) MYOCLONIC EPILEPSY WITH PHOTOSENSITIVITY IN RHODESIAN RIDGEBACKS
	F Wieläender, F James, MA Cortez, G Kluger, M Kornberg, A Bathen‐Noethen, T Flegel, S Bhatti, V Hülsmeyer, H Lohi, A Fischer
	5) LONG‐TERM TREATMENT OF CANINE PAROXYSMAL DYSKINESIAS WITH FLUOXETINE: 6 CASES
	T Bouzouraa, C Escriou
	6) INTERICTAL CARDIAC AUTONOMIC NERVOUS SYSTEM DISTURBANCES IN DOGS WITH IDIOPATHIC EPILEPSY
	D Mocanu, M Musteata, GD Stanciu, M Armasu, A Baisan, G Solcan
	7) CANINE EPILEPTOID CRAMPING SYNDROME: A GLUTEN SENSITIVE PAROXYSMAL MOVEMENT DISORDER – MORE THAN A GUT FEELING
	M Lowrie, O Garden, M Hadjivassiliou, R Harvey, D Sanders, R Powell, L Garosi
11.45:	INVITED SPEAKER SESSION
	Ronald Corbee (sponsored by Hills)
	“INFLUENCE OF SUPPLEMENTS, NUTRITION ON EPILEPSY AND MOVEMENT DISORDERS”
12.30:	Lunch, exhibition and poster session (Posters attended by authors)
13.45:	FREE COMMUNICATIONS RESEARCH ABSTRACTS
	8) ALTERNATIVE NON‐MEDICAL TREATMENTS VAGAL STIMULATION, TRANSCRANIAL MAGNETIC STIMULATION IN EPILEPSY
	SFM Bhatti
	9) THE EFFECT OF IMEPITOIN, A RECENTLY DEVELOPED ANTIEPILEPTIC DRUG, ON THYROID FUNCTION TEST PARAMETERS AND FAT METABOLISM IN HEALTHY BEAGLE DOGS
	K Bossens, S Daminet, M Rick, L Duchateau, L Van Ham, S Bhatti
	10) EFFICACY OF IMEPITOIN AS FIRST CHOICE DRUG IN THE TREATMENT OF 53 NAÏVE DOGS AFFECTED BY IDIOPATHIC EPILEPSY
	A Gallucci, T Gagliardo, M Menchetti, A Ruffini, E Bianchi, A Milici, P Tosolini, A Cauduro, G Gandini
14.30:	INVITED SPEAKER SESSION
	Bas Bloem
	“RECOGNITION, CLASSIFICATION AND TREATMENT OF NEUROLOGICAL MOVEMENT DISORDERS IN HUMANS”
15.30:	Coffee break, poster exhibition and sponsors
16.00:	INVITED SPEAKER SESSION
	Bas Bloem
	“RECOGNITION, CLASSIFICATION AND TREATMENT OF NEUROLOGICAL MOVEMENT DISORDERS IN HUMANS”
16.30:	FREE COMMUNICATIONS RESEARCH ABSTRACTS
	11) VALUE OF CEREBROSPINAL FLUID ANALYSIS IN EPILEPTIC DOGS THAT LACK INTERICTAL NEUROLOGICAL ABNORMALITIES AND HAVE UNREMARKABLE MAGNETIC RESONANCE IMAGING OF THE BRAIN
	AM Coelho, T Maddox, D Sanchez‐Masian, R Gonçalves
16.00:	INVITED SPEAKER SESSION
	Dennis O'Brien
	“MOVEMENT DISORDERS IN ANIMALS: TERMINOLOGY, CLASSIFICATION” Part 1
17.30:	Annual General Meeting (AGM) of the European Society and College of Veterinary Neurology
17.30:	Closing of the day
SATURDAY 19 TH SEPTEMBER
08.00:	Registration
08.30:	INVITED SPEAKER SESSION
	Dennis O'Brien
	“MOVEMENT DISORDERS IN ANIMALS: TERMINOLOGY, CLASSIFICATION” Part 2
09.30:	FREE COMMUNICATIONS RESEARCH ABSTRACTS
	12) PHENOTYPIC CHARACTERIZATION OF SPINNING AND TAIL‐CHASING IN GERMAN SHEPHERD AND JACK RUSSELL TERRIER
	C Escriou, J Meynet, C Dufaure de Citres, A Thomas
	13) VLDLR‐ASSOCIATED CEREBELLAR HYPOPLASIA IN EURASIER DOGS
	A Fischer, K Rentmeister, S Lindsteding, F Bernardino, E Manz
10.00:	INVITED SPEAKER SESSION
	Caroline Hahn
	“MOVEMENT DISORDERS IN LARGE ANIMALS”
10.15:	Coffee break, poster exhibition and sponsors
10.45:	INVITED SPEAKERS SESSION
	Angelica Richter and Franziska Richter
	“WHAT CAN WE LEARN FROM ANIMAL MODELS OF DYSTONIA/DYSKINESIAS IN VETERINARY AND HUMAN NEUROLOGY”
	Clare Rusbridge
	“MRI PROTOCOL IN EPILEPSY, MOVEMENT DISORDER CASES AND AN OUTLOOK FOR THE FUTURE”
11.45:	FREE COMMUNICATIONS RESEARCH ABSTRACTS
	14) COMPUTER SIMULATION OF THE CANINE SPINE: THE EFFECTS OF INCREASED SPINAL CORD MOTION ON THE DEVELOPEMNT OF SYRINGOMYELIA
	R Lloyd, S Cirovic, J Jovanovik, H Volk, C Rusbridge
	15) A PRELIMINARY STUDY OF THE PENLIGHT‐COVER TEST IN DIFFERENTIATING BETWEEN PERIPHERAL AND CENTRAL VESTIBULAR DISEASE IN DOGS AND CATS
	GE Longson, C Turner, AE Vanhaesebrouck, EJ Ives, TL Williams, PM Freeman
12.30:	Lunch, exhibition and poster session (Posters attended by authors)
14.00:	INVITED SPEAKERS SESSION
	Hans Stroink, Dennis O'Brien and Angelica Richter
	Video sessions with the audience and voting system: “HOW MUCH DO WE THINK WE KNOW…”
14.45:	FREE COMMUNICATIONS RESEARCH ABSTRACTS
	16) INTERLEUKIN‐17 AND CD40 LIGAND IN CANINE STEROID‐RESPONSIVE MENINGITIS‐ARTERITIS
	J Freundt Revilla, R Carlson, A Maiolini, A Tipold
	17) MORPHOLOGICAL RECLASSIFICATION OF IMMUNE‐MEDIATED NEUROPATHIES (IMPN) IN DOGS AND CATS: BEYOND THE CONCEPT OF AXONAL AND DEMYELINATING DISEASE
	S Gross, M Rosati, L Matiasek, D Corlazzoli, R Capello, T Harcourt‐Brown, A Fischer, V Huelsmeyer, H Schenk, G Gandini, K Gnirs, A Jeandel, M Baroni, S Loderstedt, T Flegel, K Jurina, G Abbiati, K Matiasek
	18) IMMUNOHISTOCHEMICAL CHARACTERIZATION OF THE ANTI‐INFLAMMATORY EFFECT OF TWO TREATMENT PROTOCOLS IN DOGS WITH GRANULOMATOUS MENINGOENCEPHALOMYELITIS OR NECROTIZING (MENINGO)‐ENCEPHALITIS
	F Salger, A Oevermann, L Kreipe, T Flegel, M Vandevelde, B Vidondo Curras, D Henke
15.30:	Coffee break, exhibition and poster session
16.00:	FREE COMMUNICATIONS RESEARCH ABSTRACTS
	19) CLINICAL, IMAGING CHARACTERISTICS AND LONG TERM OUTCOME OF DOGS WITH INTRANASAL MENINGOENCEPHALOCELE: A CASE SERIES
	K Lazzerini, J Guevar, G Hammond, F McConnell, J McMurrough, R Goncalves, R Gutierrez‐Quintana
	20) MULTIPLE THORACOLUMBAR PARTIAL LATERAL CORPECTOMIES IN 17 DOGS
	S Hanemann, M Münch, K Held, F Salger, L Ziegler, P Böttcher, T. Flegel
	21) COMPARISON OF CONVENTIONAL AND HIGH DEFINITION VIDEO TELESCOPE ASSISTED VENTRAL SLOT DECOMPRESSION FOR CERVICAL INTERVERTEBRAL DISC HERNIATION IN 51 DOGS
	D Rossetti, C Ricco, G Ragetly, C Poncet
	22) ACQUISITION OF INVOLUNTARY SPINAL LOCOMOTION (SPINAL WALKING) IN DOGS WITH IRREVERSIBLE THORACO‐LUMBAR SPINAL CORD LESION: A RETROSPECTIVE STUDY ON 81 DOGS
	A Gallucci, G Gandini, M Menchetti, T Gagliardo, M Pietra, M Cardinali, L Dragone
	23) ROLE OF THERAPY WITH GROWTH FACTORS IN THE MANAGEMENT OF PAIN PERCEPTION NEGATIVE DOGS CAUSED BY THORACOLUMBAR DISK EXTRUSIONS
	D Faissler, E Rozanski, M Kowaleski
	24) IDENTIFICATION OF BEHAVIORAL STATES IN CANINE NEONATES AND THEIR INFLUENCE ON NEUROLOGICAL EXAMINATION
	C Morale, J Fatjó, P Montoliu
17.45:	Boehringer Ingelheim and John Presthus Awards
18.00:	Closing remarks

ORAL PRESENTATIONS

Epileptoid cramping syndrome in the Norwich terrier: clinical characterisation and prevalence in the UK

L. De Risio, J. Freeman

Neurology Unit, Animal Health Trust, Newmarket, UK

Episodic muscular hypertonicity in Norwich terriers (NT) was first reported in a brief letter in the Veterinary Record in 1984. Since then there have been anecdotal reports and the condition has remained poorly characterized. The aims of this study were to characterize clinically NT epileptoid cramping syndrome (ECS), and to estimate its prevalence in the UK.

The owners of NT born since 1 January 2000 were invited by the UK Kennel Club and NT Breed Club to complete a specifically designed questionnaire aimed at identifying affected and unaffected NT, and clarifying the clinical characteristics of NTECS.

The questionnaire was returned for 198 NT. Of these, 26 (13%) NT were classified as affected by NTECS following revision of the questionnaires, videos of the episodes, veterinary medical records and telephone interview with the owners. All NT were clinically normal between episodes. No significant abnormalities were detected on diagnostic investigations, including electroencephalography (which was performed in 2 NT). Mean age at the first episode of NTECS was 3 years. The episodes were characterized by sustained muscular hypertonicity, dystonia of the pelvic or all 4 limbs, and difficulty or inability standing up and walking. Consciousness was normal. Episode frequency varied both between and within individuals. Stress, anxiety, excitement, and variation in daily routine were recognized as episode triggers in 13 NT. Episode duration was 2–5 minutes in the majority of NT (range <1–30 minutes).

Several affected NT were genetically related. Genetic investigations to identify causal mutations are in progress.

Degenerative encephalopathy of Nova Scotia duck tolling retrievers

E. Barker¹, D. O'Brien², L. Dawson¹, G. Johnson², J. Rose¹, S. Van Meervenne³, K. Sörensen⁴, C. Rohdin⁴, A. Leijon⁵, O. Frykman⁶, N. Granger¹

¹University of Bristol, Bristol, UK, ²University of Missouri, Columbia, MO, USA, ³AniCura Läckeby Djursjukhus, Läckeby, Sweden, ⁴National Veterinary Institute SVA , Uppsala, Sweden, ⁵Department of Biomedical Sciences and Veterinary Public Health, Section of Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden, ⁶Herrgårdskliniken, Aneby, Sweden

Hereditary neurodegenerative diseases have been reported in both human and veterinary literature. Clinical signs are often progressive, but may be delayed in onset, and typically reflect the area of the central nervous system most affected most altered pathologically.

Eight young adult Nova Scotia duck‐tolling retrievers (NSDTRs) from Sweden, Canada and UK have been evaluated for neurological dysfunction in the last two years. The aim of this study was to characterize the clinical and histopathological features of this disease.

Clinical history, MRI imaging and laboratory analysis were retrospectively reviewed. Nervous tissue was collected prospectively from selected cases following owner decision to euthanize on welfare grounds.

Neurological dysfunction was reported from four months to five years of age, and was progressive in nature. Clinical signs were characterized by marked sleep disorder (paddling, vocalization), increased anxiety, noise phobia, and gait abnormalities. MRI documented bilateral symmetrical changes predominately in the caudate nuclei. In one case these were shown to be progressive. Clinicopathological analysis of blood and CSF, infectious disease screening and urine metabolite screening were unremarkable. Post‐mortem examination of brain tissue identified malacia of the caudate nucleus as the most marked and consistent finding. Genealogical analysis supports an autosomal recessive mode of inheritance.

In conclusion a degenerative encephalopathy has been identified in young adult NSDTRs, with a worldwide distribution. MRI and histopathological lesions are characteristic. The prognosis is guarded due to progressive disease, which is minimally responsive to empirical treatment.

Epileptogenic electroencephalographic findings in canine episodic head tremor syndrome

F.M.K. James¹, S. Dugas², M.A. Cortez³, S. Sanders⁴, L. Barnard¹, G. Leblond¹, T. Jokinen⁵, H. Lohi⁶

¹Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada, ²Southern California Veterinary Specialty Hospital, Irvine, California, USA, ³Neurosciences and Mental Health Program, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Toronto, Ontario, Canada, ⁴Seattle Veterinary Specialists, Kirkland, Washington, USA, ⁵Department of Clinical Veterinary Sciences, University of Helsinki, Helsinki, Finland, ⁶Department of Medical Genetics, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland

Canine episodic head tremor syndrome (CEHTS) is considered a benign paroxysmal movement disorder of unknown pathogenesis. CEHTS is diagnosed based on signalment, history, and clinical description. Electroencephalographic (EEG) investigation into this condition has only been reported in Doberman Pinschers and was unrewarding. However, EEG abnormalities were reported in focal juvenile canine epilepsies that presented with tremor. It was hypothesized that further EEG recording of CEHTS would help to clarify nature of the pathogenesis. Ten dogs clinically diagnosed with CEHTS and video confirmation of tremor underwent video or routine EEG recording with client consent for our multicenter collaboration. There were 6 English Bulldogs and one each of Labrador retriever, Boxer, Lapponian Herder, and Alaskan Klee Kai. Four dogs demonstrated head tremor during video‐EEG recording. In three cases (one each of Boxer, Bulldog, and Lapponian Herder) , there were ictal EEG abnormalities that consisted of right‐sided predominant 6 Hz spike‐and‐wave discharges associated with the head tremor. In the remaining case (Alaskan Klee Kai) , a 12–14 Hz polyspike‐and‐wave pattern was recorded. Of the six dogs that did not demonstrate tremor during recording, there were no ictal EEG abnormalities.

These findings support the reclassification of CEHTS as an epileptic syndrome of 6 Hz spike‐and‐wave with focal onset seizures in some dogs.

Further investigation is required to determine whether there are breed‐specific differences and whether the presence of ictal or interictal patterns correlates with the natural history of the syndrome or treatment outcomes. Video‐EEG facilitates the proper diagnosis of epileptic‐like syndromes for subsequent genetic analysis.

Myoclonic epilepsy with photosensitivity in rhodesian ridgebacks

F. Wielaender¹, F. James², M.A. Cortez³, G. Kluger⁴, M. Kornberg⁵, A. Bathen‐Noethen⁶, T. Flegel⁷, S. Bhatti⁸, V. Hülsmeyer¹, H. Lohi⁹, A. Fischer¹

¹Centre for Clinical Veterinary Medicine, LMU University of Munich, Munich, Germany, ²Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Ontario, Canada, ³Neurosciences and Mental Health Program, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Ontario Canada, ⁴Department of Neuropediatrics, Epilepsy Center, Vogtareuth, Germany and Paracelsus Medical University, Salzburg, Austria, ⁵Veterinary Hospital Trier, Trier, Germany, ⁶Veterinary Practice Bathen‐Noethen, Cologne, Germany, ⁷Department of Small Animal Medicine, University of Leipzig, Leipzig, Germany, ⁸Department of Small Animal Medicine and Clinical Biology, Ghent University, Belgium, ⁹Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland

A breed‐specific syndrome characterized by frequent myoclonic jerks has been observed in Rhodesian Ridgebacks. The aim of the study was to provide a clinical and electroencephalographic description of this syndrome and to investigate its epileptic nature.

Seventeen dogs that shared a unique phenotype were identified. Owners were asked to provide a videotape and to complete an online‐questionnaire. Extensive diagnostic work‐up was offered and pedigrees were analyzed. Awake ambulatory wireless video‐electroencephalography (EEG) was performed in 11 affected Rhodesian Ridgebacks and five controls of the same breed. One dog underwent an additional video‐EEG with photic stimulation in a neuropediatric epilepsy center. EEG was reviewed by a neurophysiologist, a neuropediatrician, and three veterinarians, with consensus results reported.

Violent myoclonic jerks occurred in a recumbent and relaxed, drowsy or asleep state (n = 17) and occasionally also while standing (n = 10). In five dogs myoclonic seizures could be triggered by flashing lights. Median age of onset was 6 months (9w ‐ 1.5y). Over time seven dogs additionally developed other seizure types. Video‐EEG confirmed the diagnosis of a myoclonic epilepsy in affected dogs. One dog showed photomyoclonic responses on video‐EEG with photic stimulation. Control dogs displayed unremarkable EEG findings. None of the performed examinations (MRI, CSF, neurometabolic screening) demonstrated an underlying structural or metabolic cause. Pedigree analyses pointed to an hereditary disorder.

Rhodesian Ridgebacks suffer from an idiopathic (genetic) myoclonic epilepsy with photosensitivity. Affected dogs show a characteristic EEG pattern. This is proposed as the definition of a peculiar electroclinical syndrome whose genetic base is currently under investigation.

Long‐term treatment of canine paroxysmal dyskinesias with fluoxetine: 6 cases

T. Bouzouraa¹, C. Escriou²

¹Internal Medicine, VetAgro Sup, Lyon, France, ²Neurology, VetAgro Sup, Lyon, France

It is only recently that both clinical features and genetic basis of canine paroxysmal dyskinesias (CPDs) have been documented. Their management remains challenging though phenothiazine, benzodiazepines even anticonvulsants yielded unsatisfactory results. Fluoxetine, a selective serotonin reuptake inhibitor, seems promising.

Three Scottish terriers (STs), 2 Cavalier King Charles Spaniels (CKCSs) suffering from Scottie Cramp (SC) and Episodic Falling, respectively, then an English Setter with a dyskinesia of unknown origin, displayed many daily episodes, triggered by exercise and/or excitement that definitely preventing them from living normally. All dogs received fluoxetine as a single treatment (2–4 mg/kg q24 h). Four dogs displayed early and complete remissions that persisted over long periods (1 year for 1 CKCS then 2, 6 and 7 years for the 3 STs). The remaining 2 cases showed a significant improvement with a decline to approximately one single episode every 2 months for both dogs. Transient relapses occurred when treatment was interrupted or tapered in 3 dogs. No treatment resistance or side effect was observed.

Fluoxetine may be a good and safe option for the long‐term management of CPDs, allowing dogs for resuming to normal activity and lifestyle. It can directly correct serotoninergic transmission imbalance suspected in SC. Its activity remains unclear in other CPDs; direct serotoninergic action is likely but indirect effect through a reduction of behavioral reactivity to triggering factors like stress, excitation or environmental stimulations is also plausible.

Interictal cardiac autonomic nervous system disturbances in dogs with idiopathic epilepsy

D. Mocanu, M. Musteata, G.D. Stanciu, M. Armasu, A. Baisan, G. Solcan

Department of Clinical Science, Internal Medicine, Faculty of Veterinary Medicine Iași, Romania

Up to 65% of dogs with idiopathic epilepsy (IE) have an abnormal EEG in the interictal phase, but no neurological deficits or other positive findings on imagistic and blood examination are observed at that moment. In humans, an impaired activity of autonomic nervous system (ANS) is seen in the interictal phase of IE patients and appears to have an important role in long‐term prognosis of the cases. Until now there are no reports in which ANS is analyzed in dogs with IE.

To asses ANS we used time domain and spectral power analysis of heart rate variability (HRV) on 5 minutes ECG day time recordings in 26 newly diagnosed and chronic IE dogs with positive EEG epileptic discharges The control group was represented by 13 healthy dogs, age and weight matched. Cardiac depolarization time was assessed by measuring P wave dispersion (PWD) and corrected QT interval in all dogs.

There were no differences between IE and normal dogs in overall HRV (SDANN and LF/HF), but a significant increase in vagal tone (HF and pNN50%), PWD and QT interval was observed in the epileptic group. Those are proved triggers for sever cardiac arrhythmias in dogs (atrial fibrillation and ventricular tachyarrhythmia) and are involved in the pathogenesis of sudden death epileptic syndrome in humans.

In conclusion, dogs with subclinical brain epileptic activity have a permanent alteration in cardiac ANS function. These changes may have a contribution in increasing the risk of premature death in dogs with IE.

Canine epileptoid cramping syndrome: a gluten sensitive paroxysmal movement disorder – more than a gut feeling

M. Lowrie¹, O. Garden², M. Hadjivassiliou³, R. Harvey⁴, D. Sanders⁵, R. Powell⁶, L. Garosi¹

¹Davies Veterinary Specialists, Higham Gobion, Hitchin, UK, ²Department of Clinical Sciences and Services, Royal Veterinary College, Hatfield, UK, ³Department of Neurology, Royal Hallamshire Hospital, Sheffield, UK, ⁴Department of Pharmacology, UCL School of Pharmacy, London, UK, ⁵Department of Gastroenterology, Royal Hallamshire Hospital, Sheffield, UK, ⁶Powell Torrance Diagnostic Services, Higham Gobion, Hitchin, UK

Canine epileptoid cramping syndrome (CECS) is a paroxysmal movement disorder of Border terriers (BTs). Previous work has suggested these dogs may respond to a gluten‐free diet. The objective of this study was to investigate the possibility of an immune response to gluten and to study the effect of a gluten‐free diet in BTs with CECS. Our hypothesis was that CECS is a manifestation of gluten sensitivity.

Six BTs with clinically confirmed CECS were tested for anti‐transglutaminase 2 (TG2 IgA) and anti‐gliadin (AGA IgG) antibodies in the serum at presentation, and subsequently three, six and nine months after the introduction of a gluten‐free diet. Duodenal biopsies were performed in one patient. Serum samples were also collected from five BTs having medical investigations for conditions unrelated to neurological or gastrointestinal disease to serve as healthy controls.

Serum TG2 IgA titers were increased in 6/6 BTs and AGA IgG titers were increased in 5/6 BTs at presentation compared to controls. After nine months there was clinical and serological improvement in all BTs with CECS strictly adherent to a gluten‐free diet. One dog had persistently increased antibody titers, but was found to have scavenged horse manure. On the strict introduction of a gluten‐free diet this dog also had an improved clinical and serological response. The diet‐associated improvement was reversible in two dogs on completion of the study, both of which suffered a clinical relapse of CECS on the re‐introduction of gluten.

CECS is best described as a gluten sensitive movement disorder triggered and perpetuated by gluten and thus responsive to a gluten‐free diet.

Alternative non‐medical treatments vagal stimulation, transcranial magnetic stimulation in epilepsy

S.F.M. Bhatti

Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium

Neurostimulation is a treatment modality in which electrical pulses are administered to nerve tissue in order to manipulate a pathological substrate and to achieve a symptomatic or even curative therapeutic effect. In human epilepsy, a substantial number of patients either lack good seizure control with pharmacological or surgical treatment, or they experience major adverse effects (or both). Therefore, neurostimulation‐based treatments have gained considerable interest the last 10–15 years.

Electrical stimulation of the tenth cranial nerve or vagus nerve stimulation (VNS) is an extracranial form of neurostimulation that was developed in the 1980s and is currently routinely and worldwide available for the management of human epilepsy. VNS is indicated in patients with refractory epilepsy who are unsuitable candidates for epilepsy surgery or who have had insufficient benefit from such a treatment. VNS influences crucial brainstem and intracranial structures including the nucleus of the solitary tract, the locus coeruleus, the thalamus, and limbic structures. The precise mechanism of action (MOA) by which VNS exerts its antiepileptic effect is still unknown. The current consensus on efficacy is that one third of patients have a considerable improvement in seizure control with a reduction in seizure frequency of at least 50%, one third of patients experience a worthwhile reduction in seizure frequency between 30% and 50%, and the remaining one third of patients experience little or no effect. Increased insight into the MOA may help to identify responders and increase clinical efficacy.

Also, from a veterinary point of view, research towards neurostimulatory treatments for refractory canine epilepsy is needed. Only one study evaluated the efficacy and safety of VNS in dogs with idiopathic epilepsy and the results seemed promising. We examined the MOA of VNS in healthy Beagle dogs and demonstrated changes in cerebral perfusion using µ‐SPECT and increases in CSF norepinephrine concentrations induced by VNS.

The effect of imepitoin, a recently developed antiepileptic drug, on thyroid function test parameters and fat metabolism in healthy beagle dogs

K. Bossens¹, S. Daminet¹, M. Rick², L. Duchateau³, L. Van Ham¹, S. Bhatti¹

¹Department of Small Animal Medicine and Clinical Biology, Ghent University, Belgium, ²Department of Pathobiology and Diagnostic Investigation, Michigan State University, USA, ³Department of Physiology and Biometrics, Faculty of Veterinary Medicine, Ghent University, Belgium

Since early 2013, imepitoin has been introduced in most European countries for the management of recurrent single generalized epileptic seizures in dogs with idiopathic epilepsy. It has been demonstrated that imepitoin is similarly effective as phenobarbital in controlling seizures in dogs with newly diagnosed idiopathic epilepsy. Furthermore, a clinically significant superior safety profile was shown compared to phenobarbital administration. As the use of imepitoin gains popularity, its effect on serum thyroid function test parameters warrants further investigation. It is well known that long‐term phenobarbital administration influences thyroid function test parameters in dogs. This alteration in serum thyroid hormone concentrations can lead to misinterpretation of results and incorrect diagnosis of thyroidal illness.

A prospective study was conducted to compare the effect of phenobarbital and imepitoin on serum concentrations of total thyroxine (TT4), triiodothyronine, free thyroxine, thyroglobulin auto‐antibodies, thyroid‐stimulating hormone, cholesterol and triglycerides in healthy Beagle dogs. These parameters were determined prior to initiation of antiepileptic drug administration, and after 6, 12 and 18 weeks of antiepileptic drug administration. The oral starting dose of phenobarbital was 5 mg/kg PO q12 h and was monitored and adjusted to obtain optimal therapeutic serum concentrations (30–35 µg/mL). Imepitoin was given at 30 mg/kg PO q12 h.

The results of our study showed that, firstly, imepitoin administration did not affect mean serum TT4 concentrations over an 18‐week period. In contrast, mean serum TT4 concentrations decreased significantly over time in dogs where phenobarbital was administered. Secondly, mean serum cholesterol concentrations increased significantly over time in the dogs on imepitoin but not to the same extent as commonly seen in dogs with primary hypothyroidism.

Efficacy of imepitoin as first choice drug in the treatment of 53 naïve dogs affected by idiopathic epilepsy

A. Gallucci¹, T. Gagliardo¹, M. Menchetti¹, A. Ruffini¹, E. Bianchi^1,2, A. Milici³, P. Tosolini⁴, A. Cauduro⁵, G. Gandini¹

¹Department of Veterinary Medical Sciences, University of Bologna, Ozzano Emilia, Italy, ²Department of Veterinary Medical Sciences, University of Parma, Parma, Italy, ³Veterinary Clinic “Città di Saronno”, Saronno, Italy, ⁴Veterinary Clinic “Schiavi”, Udine, Italy, ⁵Veterinary Clinic, Legnano, Italy

The efficacy and safety of Imepitoin, a novel antiepileptic drug, were retrospectively evaluated in 53 naïve idiopathic epileptic dogs that met the inclusion criteria (diagnosis of Idiopathic Epilepsy and Imepitoin monotherapy).

Follow‐up information was obtained through a questionnaire sent to the owners: 53 (100%), 35 (66%) and 13 (25%) dogs had follow‐up information at 3, 6 and 9 months, respectively.

Imepitoin starting dosage (expressed as mg/kg BID) was 8–10 in 11 dogs (21%), 11–20 in 40 dogs (75%) and 21–30 in 2 dogs (4%). During time, dosage was increased in 20 dogs (34%), becoming 11–20 mg/kg in 39 dogs (74%) and 21–30 mg/kg in 10 dogs (19%).

Successful treatment, defined as >50% reduction in seizures was noted in 25 (47%), in 20 (57%) and 9 (69%) dogs at 3, 6 and 9‐months follow‐up, respectively. Complete remission was achieved in 15 (28%), 9 (26%) and 3 (23%) dogs at 3, 6 and 9‐months follow‐up. Cluster seizures (before treatment: n = 16, 30%) turned to single seizures in 8 (15%), 4 (11%) and 1 (8%) at 3, 6 and 9 months follow‐up.

Side effects were observed in 19 dogs (36%) and consisted in transient sedation/somnolence, hyperexcitability, aggressiveness, tremors, gastrointestinal problems. Two dogs still showed mild aggressiveness in long term.

Lack of efficacy and consequent change/association of drug was the reason for 9 and 11 dogs that missed the follow‐up at 6 and 9 months.

In this study Imepitoin showed its major efficacy at a dosage >15 mg/kg BID. Side effects were mild and, mostly, transient.

Value of cerebrospinal fluid analysis in epileptic dogs that lack interictal neurological abnormalities and have unremarkable magnetic resonance imaging of the brain

A.M. Coelho, T. Maddox, D. Sanchez‐Masian, R. Gonçalves

Small Animal Teaching Hospital, University of Liverpool, Neston, UK

To diagnose idiopathic epilepsy (IE), CSF analysis is essential to exclude other causes of seizures. Dogs with interictal neurological deficits are likely to have a underlying brain disease but the value of performing CSF analysis in dogs that lack interictal changes and have normal advanced imaging of the brain has not yet been assessed.

The database of the University of Liverpool was searched for dogs presenting for recurrent seizures with no interictal abnormalities according to the owners. Inclusion criteria for the study comprised an unremarkable neurological examination, exclusion of possible causes of reactive seizures (including a normal hematology and biochemistry profiles) and normal magnetic resonance (1‐Tesla) of the brain. Results of the CSF analysis in these patients were evaluated and considerate abnormal if the protein concentration was >30 mg/dl and/or the total nucleated cell count was >5cells/μL. Dogs were excluded if the CSF RBC count was >5000 μl.

A total of 120 dogs met the inclusion criteria. An abnormal CSF was only found in 5.8% (7/120) of dogs. The prevalence found for diagnosis other than IE was 1/120 dogs (0.8%). The site of CSF sampling, the interval between last seizure and CSF collection and the seizure type had no correlation with having an abnormal CSF. The number of red blood cells in the sample was significantly different between dogs with normal and abnormal CSF (P = 0.016).

These results suggest that CSF analysis has a poor incremental diagnostic value for other than idiopathic epilepsy in patients with the same inclusion criteria of this study.

Phenotypic characterization of spinning and tail‐chasing in German shepherd and Jack Russell terrier

C. Escriou¹, J. Meynet¹, C. Dufaure de Citres², A. Thomas²

¹Neurology, VetAgro Sup, Lyon Veterinary Campus, France, ²Antagène, France

A predisposition to develop “spinning” (S) and “tail chasing” (TC) behavior has been observed in Bull Terriers (BT). These stereotypic behaviors are related to Obsessive Compulsive Disorder (OCD) and genetic basis have been demonstrated. Signs of hallucination and psychotic like behavior (freezing, staring, unprovoked aggression, unexplained growling, fly catching) are commonly associated and a complex neurological and evolutive syndrome related to autism is suspected were OCD coexists with focal/partial seizures.

In order to determine if others breeds could be affected by this disease, we recruited other dogs than BT affected by spinning or tail‐chasing using a web questionnaire. We recruited 20 German Shepherd (GS) and 14 Jack Russell Terrier (JRT). A precise phenotypic characterization could have been done and compared to BT's one. As in BT, we describe an association between spinning/tail chasing and psychotic like behavior with alteration of dog's personality. Trance like behavior were observed in a majority of dogs with disconnection from the environment during episodes. Same stages of disorders reflecting the severity and evolutive nature of the disease were applied to GS or JRT as for BT. Some minor breed specificities seems to exists as high spinning velocity in JRT, spinning with tail in the mouth in JRT and GS (but not in BT) for example.

Spinning or tail chasing in GH and JRT must be considered as the same complex neurobehavioral disease as in BT although its prevalence in this breeds seems to be lower than in BT.

VLDLR‐associated cerebellar hypoplasia in Eurasier dogs

A. Fischer¹, K. Rentmeister², S. Lindsteding³, F. Bernardino¹, E. Manz⁴

¹Centre for Clinical Veterinary Medicine, LMU University of Munich, Munich, Germany, ²Tierärztliche Praxis für Neurologie, Dettelbach, Germany, ³Kynologische Zuchtgemeinschaft Eurasier e. V.¸ Germany, ⁴Generatio Sol. GmbH, Heidelberg, Germany

The very low density lipoprotein receptor (VLDLR) is part of the reelin signaling pathway, which directs neuroblast migration. VLDLR‐associated cerebellar hypoplasia in Eurasier dogs is an autosomal recessive inherited cerebellar malformation due to a one base pair deletion in the very low density lipoprotein receptor (Gerber et al., 2015). It is characterized by absence of the caudal portions of the cerebellar vermis and the cerebellar hemispheres, large retrocerebellar fluid accumulations, enlarged fourth ventricle and variable caudal fossa size (Bernardino et al., 2015). Non‐progressive ataxia is the main neurologic sign. Phenotypic variation in the severity of the ataxia may occur, ranging from severe cerebellar ataxia in puppies, to improved ataxia in adults, and an almost normal gait in one affected dog despite the presence of a severely hypoplastic cerebellum.

Therefore the aim of the present investigation was to estimate the prevalence of the VLDLR:c.1713delC mutation in a population of Eurasier dogs. EDTA blood samples from 397 Eurasier dogs were collected in association with the respective breed club and stored frozen at −20°C until further analysis. Genetic testing for the VLDLR‐mutation was done as described previously (Gerber et al., 2015).

Results identified 46 heterozygous carriers of the mutation and indicated an estimated prevalence of 11.59% (CI95% 8.44% –14.74%). In conclusion, the VLDLR:c.1713delC mutation has a high prevalence in this population. Genetic testing is recommended prior to breeding in any Eurasier dog to avoid breeding carriers to each other, and also as a simple diagnostic tool in any Eurasier dog with non‐progressive ataxia.

Computer simulation of the canine spine: the effects of increased spinal cord motion on the developemnt of Syringomyelia

R. Lloyd¹, S. Cirovic¹, J. Jovanovik², H. Volk³, C. Rusbridge^2,4

¹Department of Mechanical Engineering Sciences, University of Surrey Guildford, Surrey, UK, ²Fitzpatrick Referrals, Godalming, Surrey, UK, ³Royal Veterinary College, University of London, London, UK, ⁴School of Veterinary Medicine, University of Surrey, Guildford, Surrey, UK

Syringomyelia is a disorder characterized with the presence of fluid‐filled cavities in the spinal cord. The condition occurs in both humans and animals. The mechanism(s) of cavity formation are not clear, leading to limited treatment. Current theories are based on the assumption that abnormities in the circulation of the cerebrospinal fluid (CSF) generates pressures that drive the fluid into the cord.

A finite element model was constructed using geometry extracted from MRI scans of a Cavalier King Charles spaniel with syringomyelia, to explore possible mechanisms of syrinx formation. The model included the spinal cord, subarachnoid space (SAS), dura mater, and the epidural space. It has been shown in patients with restricted CSF flow, that there is exaggerated movement of the spinal cord during the cardiac cycle. This motion was applied to the cranial end of the spinal cord of the model.

The peak longitudinal and radial pressure differences in the SAS oscillated between −22.3 to +90.0 Pa, and −100 to +100 Pa, respectively. Low‐amplitude cyclic shear stresses were present in the cervical spinal cord (C2 – C6), where the cavities typically originate.

In conclusion it was proposed that the CSF pressure gradients are unlikely to cause fluid movement into the cord, sufficient to generate syrinxes. On the other hand, although the shear stress in the cord is low, its location and cyclic nature indicates the possibility that this may be the factor that generates the initial tissue damage, which eventually leads to the formation of syrinxes.

A preliminary study of the penlight‐cover test in differentiating between peripheral and central vestibular disease in dogs and cats

G.E. Longson, C. Turner, A.E. Vanhaesebrouck, E.J. Ives, T.L. Williams, P.M. Freeman

Department of Veterinary Medicine, University of Cambridge, Cambridge, UK

Differentiating between peripheral and central vestibular disease is important for clinical decision‐making and prognostication. Current diagnostic methods used for differentiation are infrequently available in general practice, require general anesthesia and carry a high cost. The penlight‐cover test (PCT) may provide a simple, safe and cost‐effective clinical test to overcome these limitations.

Masking visual input using a bright penlight should reduce suppression of spontaneous nystagmus in cases of peripheral but not central vestibular disease.

The utility of the PCT to differentiate between peripheral and central vestibular disease was evaluated by measuring changes in slow phase velocity (SPV) and beat frequency (BF) of nystagmus whilst masking visual input.

Data were collected from 5 peripheral and 8 central cases in a referral population of dogs and cats. SPV increased when visual input was removed in 60% of peripheral cases but 0% of central cases (Fisher's exact test, P = 0.035). BF increased when visual input was removed in 80% of peripheral cases but 12.5% of central cases (Fisher's exact test, P = 0.0319). The BF increased by a median of 4 beats in 7 seconds in peripheral cases and 0 beats in 7 seconds in central cases (Mann‐Whitney U test, P = 0.0193).

In conclusion, increased SPV or BF when visual input is removed may increase suspicion of peripheral vestibular disease, whereas unchanged SPV, or unchanged or decreased BF, may increase suspicion of central vestibular disease. Further studies are required to calculate the sensitivity, specificity and predictive values of the PCT in a larger population of dogs and cats.

Interleukin‐17 and CD40 ligand in canine steroid‐responsive meningitis‐arteritis

J. Freundt Revilla, R. Carlson, A. Maiolini, A. Tipold

Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany

Steroid‐Responsive Meningitis‐Arteritis (SRMA) is an immune mediated disorder characterized by a neutrophilic pleocytosis in the cerebrospinal fluid (CSF). Previous studies of the disease have shown increased levels of IL‐6 and TGF‐ß1 in CSF indicating the presence of Th17 lymphocytes. IL‐17 induces and mediates inflammatory responses and plays an important role in recruitment of neutrophils. The hypothesis of a Th17 skewed immune response in SRMA should be confirmed by evaluating IL‐17 and CD40L, inducing B‐T cell interaction.

Enzyme‐linked immunosorbent assays (ELISA) were performed to measure IL‐17 and CD40L in serum and CSF of patients suffering from SRMA in the acute stage (SRMA A), under treatment with glucocorticosteroids (SRMA T), during recurrence of the disease (SRMA R) and with other neurological disorders and in healthy dogs (animal experiment 05‐14A453).

Significant higher levels of IL‐17 were found in CSF of dogs with SRMA A compared with SRMA T, other neurological disorders and healthy dogs (P < 0.0001). In addition, levels of CD40L in CSF in dogs with SRMA A and SRMA R were significantly higher than in healthy controls (P < 0.05). Furthermore, CSF concentrations of IL‐17 and CD40L showed a strong positive correlation among each other (rSpear = 0.4215; P < 0.0003) and with the degree of pleocytosis (rSpear = 0.8924; P < 0.0001 and rSpear = 0.3817; P < 0.0034).

These results imply that Th17 cells are inducing the autoimmune response in SRMA and are involved in the development of the severe neutrophilic pleocytosis. The investigation of the role of IL‐17 and CD40L in SRMA adds to the knowledge of pathophysiological mechanisms in SRMA and opens the discussion about new therapeutic strategies.

Morphological reclassification of immune‐mediated neuropathies (IMPN) in dogs and cats: beyond the concept of axonal and demyelinating disease

S. Gross¹, M. Rosati¹, L. Matiasek², D. Corlazzoli³, R. Capello⁴, T. Harcourt‐Brown⁵, A. Fischer⁶, V. Huelsmeyer⁶, H. Schenk⁷, G. Gandini⁸, K. Gnirs⁹, A. Jeandel¹⁰, M. Baroni¹¹, S. Loderstedt¹², T. Flegel¹³, K. Jurina², G. Abbiati¹⁴, K. Matiasek¹

¹Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig‐Maximilians University, Munich, Germany, ²Neurology Referral Service, Tierklinik Haar, Haar, Germany, ³Clinica Veterinaria Roma Sud, Rome, Italy, ⁴North Downs Specialist Referrals, Bletchingley, Surrey, UK, ⁵Langford Veterinary Services, University of Bristol, Bristol, UK, ⁶Section of Neurology, Centre for Clinical Veterinary Medicine, Ludwig‐Maximilians University, Munich, Germany, ⁷Neurology Service, Small Animal Clinic, Lueneburg, Germany, ⁸Department of Veterinary Medical Science, University of Bologna, Italy, ⁹Advetia Clinic for Small Animal Medicine, Paris, France, ¹⁰Ecole Nationale Vétérinaire d'Alfort, Maisons Alfort, France, ¹¹Clinica Veterinaria Valdinievole, Monsummano, Italy, ¹²Neurology Service, Clinic of Small Animal Medicine, University of Berlin, Berlin, Germany, ¹³Section of Neurology, Clinic of Small Animal Medicine, University of Leipzig, Leipzig, Germany, ¹⁴Clinica Veterinaria Malpensa, Samarate, Italy

Recent developments in human Guillain‐Barre research challenge the classification of IMPN according to axonal and demyelinating features even though unsupported by morphological investigations. To contribute to this discussion, this study screened for an association of inflammatory features and fiber pathologies amongst IMPN affected nerves from dogs and cats.

Archived nerves from dogs and cats exhibiting fiber‐invasive inflammatory cells underwent duo dichromatic teasing preparation (DTP) and were reevaluated for affection of functional fiber subunits. The features were correlated to clinical records and electrophysiological data.

Altogether 19 IMPN affected dogs and 15 cats were included. In each species, the mode of inflammation and fiber degeneration gave rise to four IMPN subtypes, with affection of Schmidt‐Lanterman clefts (SLC) (9/34), nodes‐paranodes (NPN) (10/34) or both (14/34). Amongst dogs displaying NPN (9/19) two different stages were distinguished suggesting humoral immune mechanisms to precede cellular infiltrates (4/19). Feline biopsies mostly featured involvement of both subunits (12/15) at advanced stages. Electrophysiology was rarely predictive of the primarily affected subunit in pure SLC and NPN types.

Evaluation of fiber subunits provide a better insight into the immunobiology of IMPN by unraveling the primary targets. Like in humans, nodo‐paranodopathies and internodopathies can be distinguished in animals. In a strict sense, the former relates to acute motor axonal neuropathy (AMAN) while the latter corresponds to acute inflammatory demyelinating polyneuropathy (AIDP) in people. Correct IMPN subtyping by DTP is recommended in order to achieve a correct diagnosis and to base prospective clinical studies on a scientific ground.

Immunohistochemical characterization of the anti‐inflammatory effect of two treatment protocols in dogs with granulomatous meningoencephalomyelitis or necrotizing (meningo)‐encephalitis

F. Salger^1,2, A. Oevermann¹, L. Kreipe², T. Flegel³, M. Vandevelde^1,2, B. Vidondo Curras⁴, D. Henke^1,2

¹Division of Neurological Sciences, University of Leipzig, Germany, ²Division of Clinical Neurology, University of Leipzig, Germany, ³Department of Small Animal Medicine, Faculty of Veterinary Medicine, University of Leipzig, Germany, ⁴Department of Veterinary Public Health, Vetsuisse Faculty, University of Bern, Switzerland

There is little objective evidence about the effect of immunosuppressive treatment of canine granulomatous meningoencephalomyelitis (GME) and necrotizing encephalitides (NME/NLE summarized as NE).

To assess the effect of two different treatment protocols for GME and NE, the inflammatory reaction in these conditions was evaluated quantitatively and qualitatively in 18 untreated dogs (5 GME, 13 NE), in 10 dogs treated with prednisolone (4 GME, 6 NE), and in 7 dogs treated with prednisolone and lomustine (CCNU‐P) (4 GME, 3 NE) which were all euthanized because of their CNS disease or other reasons. Randomly selected areas of representative lesions were examined for the total inflammatory cell count (TCC), and the number and relative distribution of T‐lymphocytes (CD3), B‐lymphocytes (CD20) and macrophages (CD18) using immunohistochemistry.

In all untreated dogs, macrophages were the most common cell population, followed by B‐lymphocytes and much less T‐lymphocytes. The TCC was decreased following both treatment protocols as compared to untreated dogs; however, only after CCNU‐P this difference reached significance. In dogs treated with CCNU‐P for GME, all cell types, and in dogs with NME/NE specifically macrophages and T‐lymphocytes were significantly decreased.

Our results regarding the qualitative distribution of inflammatory cells were consistent with previous reports in dog with GME; however, we did not find a predominance of T‐lymphocytes in in dog with NE as reported before. The immunosuppressive effect of both treatment protocols was evident, but the CCNU‐P seems to be more effective. Interestingly, the percentage of B‐lymphocytes was much higher following treatment in dogs with NE compared to dogs with GME. This finding may imply a role for antibody mediated mechanisms in the pathogenesis of NE.

Clinical, imaging characteristics and long term outcome of dogs with intranasal meningoencephalocele: a case series

K. Lazzerini¹, J. Guevar¹, G. Hammond¹, F. McConnell², J. McMurrough³, R. Goncalves², R. Gutierrez‐Quintana¹

¹Small Animal Hospital, University of Glasgow, UK, ²Small Animal Teaching Hospital, University of Liverpool, UK, ³PetMedics, Worsley, Manchester, UK

A meningoencephalocele is a protrusion of cerebral tissue and meninges through a cranium defect. There are few case reports describing this uncommon condition in dogs. The aim of this retrospective case series is to describe the clinical presentation, magnetic resonance imaging (MRI) or necropsy features, treatment and outcome of dogs with meningoencephalocele.

Four young dogs (aged between 8 weeks and 10 months) were presented with a history of seizures. In one dog neurological examination was unremarkable. In three dogs, neurological deficits indicated a forebrain neurolocalisation. Intranasal meningoencephalocele was diagnosed with MRI in all four cases. MRI revealed signs of inflammation of herniated meninges and brain parenchyma. One dog was euthanized after MRI. Necropsy confirmed the imaging diagnosis. The three other dogs were treated with phenobarbitone. In the three cases, seizures were well controlled under treatment four months to four years after diagnosis.

In these four cases, intranasal meningoencephalocele was diagnosed with MRI in young dogs presenting with seizures. It has been hypothesized that a meningoencephalocele could be a possible seizure focus. In humans, surgical excision of the herniated brain tissue is the treatment of choice. In veterinary medicine, two cases (one dog and one cat) were described in which the neurological signs disappeared after surgical treatment. In three of the dogs presented here, adequate seizure control and good quality of life were achieved with medical treatment only. Antiepileptic treatment is a valid non invasive treatment option when there is no cerebrospinal fluid leakage and the neurological deficits are mild.

Multiple thoracolumbar partial lateral corpectomies in 17 dogs

S. Hanemann¹, M. Münch¹, K. Held¹, F. Salger², L. Ziegler³, P. Böttcher¹, T. Flegel¹

¹Department of Small Animal Medicine, University of Leipzig, Germany, ²Devision of Clinical Neurology, Vetsuisse Faculty, University of Bern, Switzerland, ³Clinic for Birds, Reptiles, Amphibians and Fish, Faculty of Veterinary Medicine, Justus Liebig University Giessen, Germany

Thoracolumbar partial lateral corpectomies (TLPLC) facilitates access to the ventral spinal canal and allows spinal cord decompression by minimizing spinal cord manipulation. In veterinary literature multiple TLPLCs have not been recommended because of potential spinal instability.

The aim of this retrospective study was to report the feasibility of multiple thoracolumbar partial lateral corpectomies in dogs with intervertebral disc disease (IVDD) and to describe the clinical outcome.

Seventeen dogs were treated by multiple TPLCs for ventral spinal cord compression caused by Hansen type I or II IVDD. The presurgical spinal cord compression and postsurgical decompression, as well as slot dimensions were measured based on computed tomography‐ myelography images. The neurological outcome was assessed based on repetitive examinations and owner questionnaires. Fourteen dogs had two TLPLCs, two dogs had three TLPLCs and one dog had four TLPLCs performed. The mean slot depth, height and length were 63%, 29% and 25% of the vertebral body, respectively. The mean residual vertebral interslot length between two adjacent TLPLCs was 65% of the vertebral body length. At re‐evaluation four weeks after surgery, seven dogs (35.3%) had the same modified Frankel Score compared to the presurgical examination, whereas eleven dogs (64.7%) had neurologically improved. According to the owners, 78.6% of the dogs showed a normal gait within six months after surgery.

In conclusion, multiple spinal cord compressions caused by IVDD can be eliminated by multiple TLPLCs. The benefit of complete spinal cord decompression at all relevant disc locations seems to outweigh the risk of potential spinal instability.

Comparison of conventional and high definition video telescope assisted ventral slot decompression for cervical intervertebral disc herniation in 51 dogs

D. Rossetti, C. Ricco, G. Ragetly, C. Poncet

Centre Hospitalier Vétérinaire Frégis, Arcueil France

The ventral slot surgery is the treatment of choice for cervical intervertebral disc disease (IVDD) in dogs. Little is known about the use of magnification in veterinary neurosurgery. The objective of this prospective study was to compare the use of a Video Telescope Operating Monitor (VITOM) with the conventional approach.

Fifty‐one dogs that presented with cervical intervertebral disc disease between June 2013 and September 2014. The dogs were assigned to a VITOM group (n = 30) or a conventional group (n = 21). Signalment, pre‐operative neurological status, preoperative spinal cord dimension at the compression level obtained with CT myelography, operative time, surgical complications, ventral slot size, postoperative spinal height and diameter at the compression level obtained with CT myelography, hospitalization time and the post‐operative outcome were compared between the two groups.

No significant differences in the surgical time were noted (62.4 ± 14.2 min, P = 0.6). The VITOM group was associated with a greater post‐operative spinal diameter (P = 0.01) and spinal height (P = 0.002) as well as a smaller ventral slot (P = 0.007) in comparison with the conventional group. The VITOM group was associated with a better post‐operative outcome (P < 0.01) and a shorter post‐operative hospitalization time (P = 0.006).

The VITOM installation was not time consuming and the learning curve was considered to be fast. The results of this study support the view that the VITOM technique could be advantageous compared with conventional ventral slot surgery.

Acquisition of involuntary spinal locomotion (spinal walking) in dogs with irreversible thoraco‐lumbar spinal cord lesion: a retrospective study on 81 dogs

A. Gallucci¹, G. Gandini¹, M. Menchetti¹, T. Gagliardo¹, M. Pietra¹, M. Cardinali², L. Dragone³

¹Department of Medical Sciences, University of Bologna, Ozzano Emilia, Italy, ²Istituto Veterinario di Novara, Novara, Italy, ³Physiotherapy and Rehabilitation Center, Dog Fitness, Reggio Emilio, Italy

Spinal walking (SW) is described as the acquisition of an involuntary motor function in paraplegic dogs and cats without deep pain perception (DPP) affected by a thoracolumbar (TL) lesion.

Aim of this retrospective study, was to evaluate the number of TL paraplegic dogs without DPP that developed an autonomous spinal walking after intensive physical rehabilitation, consisting in passive and active assisted exercises. Cornerstones of the treatment were the use of underwater treadmill, and cage restriction to avoid the dogs to drag on their hind limbs.

The medical records of 81 acute paraplegic TL dogs were selected according to the inclusion criteria (intensive rehabilitation treatment in paraplegic dogs with absence of DPP on admission and during the whole treatment). Nonparametric and parametric statistics were used to analyze possible correlation between variables and acquisition of SW.

Autonomous SW was achieved in 48 dogs (59%). 34 had intervertebral disk disease, 14 had traumatic injury. Out of these, 31 underwent surgery. Age and weight were significantly lower (P = 0.0064 and P = 0.0269) in SW than in No‐SW group. Type and site of the lesion and hospitalization were not significantly correlated to development of SW. Early start of physiotherapy and its duration, were positively associated with becoming SW (P = 0.0426 and P < 0.0001). Time of physiotherapy had a median of 86 days in SW and 64 days in No‐SW dogs.

Our data suggested that dogs with irreversible TL lesion had significant possibilities to develop SW after intensive physiotherapy treatment, especially when started soon and in lightweight dogs.

Role of therapy with growth factors in the management of pain perception negative dogs caused by thoracolumbar disk extrusions

D. Faissler, E. Rozanski, M. Kowaleski

Cummings School of Veterinary Medicine, Tufts University, North Grafton, USA

The purpose of this prospective pilot study was to examine the hypothesis that dogs with an acute onset of paraplegia and absent pain perception treated with either subdural platelet rich plasma injections or the intravenous application of erythropoietin at the time of decompressive surgery will have a higher likelihood of a functional recovery than dogs treated with surgery alone.

Inclusion criteria included chondrodystrophic dogs presenting with acute thoracolumbar disk extrusion, paraplegia, and absent pain perception. All dogs underwent decompression within 24 hours after admission and were randomly assigned to: 1) saline subdural, 2) autologous platelet rich plasma subdural or 3) erythropoietin (EPO) IV. Initial and follow‐up examinations were performed at the time of admission, and 1, 3, 7, 14, 42 and 84 days post‐surgery, with a focus on ambulation and fecal/urinary continence. Statistical analysis was performed with SPSS for Windows 20 software. The level of significance was defined as P < 0.05.

The median age of the 32 dogs enrolled was 5 years. Dachshunds were the most common breed. One dog developed myelomalacia 4 days post‐surgery and was euthanized. Three month post‐surgery 24/31 (78%) dogs regained ambulatory function whereas 7/31 (22%) did not. There was no overall difference between groups, although dogs treated with EPO had a trend towards improved overall outcome with a reduction in incontinence (Chi Square, P = 0.081).

Despite the good outcome in all the groups, the application of erythropoietin might be beneficial. Future studies should be directed towards the application of EPO in a larger group of dogs.

Identification of behavioral states in canine neonates and their influence on neurological examination

C. Morales¹, J. Fatjó², P. Montoliu¹

¹Neurocat Veterinaris, Barcelona, Spain, ²Chair Affinity Foundation Animals and Health, Department of Psychiatry and Forensic Medicine, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain

In human neonatology, behavioral state (BS) is defined as a group of physiological, motor and behavioral characteristics occurring at the same time indicating the infant´s levels of arousal. It is an extremely important variable while assessing newborns, as the same stimulus can produce different responses depending on the BS.

Our objectives were to investigate whether BS are recognizable in canine neonates by a descriptive behaviour classification and if BS can determine the responses to stimuli during neurological examination. This study obtained ethical approval.

An adaptation of the Behavioral States Scale for human infants was developed for its application in dogs. As part of a larger study with the objective to develop a standardized neonatal neurological examination procedure for dogs, serial neurologic examinations were performed in 53 beagles ranging from 0 to 13 days of age. Pup's responsiveness to seven selected stimuli (palpebral reflex, superficial skin sensation, hopping response, walking, righting reflex, withdrawal reflex and muscle tone evaluation) was assessed in each identified state.

Five distinct behavioural states could be easily identified in neonate dogs: asleep, drowsy, quiet alert, active alert, and crying. Responses to stimuli during neurological examination were observed to be influenced by BS. Thus, the optimal BS for each item was established.

Our results show that, in order to standardize neurological assessment in canine neonates, instructions need to be provided about in which BS a given item should be tested. Changes in BS during exam also suggest the need to be flexible in the sequence of neurological examination.

POSTER PRESENTATIONS

Evaluation of magnetic resonance imaging guidelines to differentiate between thoracolumbar nucleus pulposus extrusions and anulus fibrosus protrusions in large breed dogs

S. De Decker, S.A. Gomes, R.M.A. Packer, P.J. Kenny, E. Beltran, B. Parzefall, J. Fenn, D. Nair, G. Nye, H.A. Volk

The Royal Veterinary College, University of London, Hatfield, UK

Four MRI variables have recently been identified, which are independently associated with a diagnosis of thoracolumbar nucleus pulposus extrusion (NPE) or anulus fibrosus protrusion (AFP). Midline intervertebral disk (IVD) herniation, and partial IVD degeneration were associated with AFP, while presence of a single IVD herniation and disk material dispersed beyond the boundaries of the IVD space were associated with NPE. The aim of this study was to evaluate if using these MRI variables improves differentiation between NPE and AFP.

No ethical approval was required for this study. Eighty large breed dogs with surgically confirmed thoracolumbar NPE or AFP that underwent MRI were included. Studies were randomized and presented on 2 occasions to 6 blinded observers, which were divided into 3 experience categories. During the first assessment, observers made a presumptive diagnosis of thoracolumbar NPE or AFP without guidelines. During the second assessment they were asked to make a presumptive diagnosis with the aid of guidelines. Additionally, they were asked to record the presence or absence of each MRI variable. Agreement was evaluated by Kappa‐statistics.

Diagnostic accuracy improved from 70.8% to 79.6% and inter‐observer agreement for making a diagnosis of NPE or AFP improved from fair (κ = 0.27) to moderate (κ = 0.41) after using the proposed guidelines. Diagnostic accuracy was influenced by degree of observer experience. Intra‐observer agreement for the assessed variables was variable, while inter‐observer agreement ranged from fair to moderate.

The results of this study suggest that the proposed imaging guidelines can aid in differentiating thoracolumbar NPE from AFP.

Familial ovine episodic ataxia

I.G.J. Mayhew, R.D. Jolly, D. Burnham, A.I. Ridler, G.J. Poff, H.T. Blair

IVABS, Massey University, Palmerston North, New Zealand

A similar episodic neurological disorder occurred in crossbred lambs on 2 properties and in a proportion of lambs born to a sire from each property. Some lambs were abnormal at birth, tended to adopt a head and neck extended posture and were slow to get to their feet and suckle when they then became apparently normal. When forced to move, they and other more robust lambs elicited an asymmetric gait, base‐wide extensor hypertonia (hypometria) of thoracic limbs and flexor hypertonia (hypermetria) of pelvic limbs. In some there was variable nystagmus. After several meters of asymmetric ataxic gait they would fall to one side, sometimes adopting a sitting position. Recovery usually occurred in one to several minutes. As lambs aged, it became more difficult to elicit the episodes of dysfunction and by 6 months of age they appeared normal.

The disorder was diagnosed as a dominant familial episodic cerebellovestibular ataxia inherited as a dominant trait, with incomplete penetration of observed clinical signs and variable expressivity. A proportion of affected lambs are likely to die in the neonatal period so the specific nature of the disorder may go unrecognized. Because of incomplete penetrance and varying expressivity, many of the lambs carrying this mutation will survive without showing clinical signs and may enter breeding flocks, where the disorder may be perpetuated and contribute to neonatal deaths. Several genes involved with episodic ataxias in rodents and humans have been assessed in affected sheep and have been inconclusive to date.

The sero‐prevalence of anti‐glycolipid antibodies in acute canine polyradiculoneuritis and other peripheral and cranial neuropathies, neuromuscular disorders and myopathies – interim report

A. Rupp¹, S.K. Halstead², J. Penderis³, E. Bianchi⁴, M. Dondi⁴, H.A. Volk⁵, S. Bhatti⁶, A. Pakozdy⁷, G. Gandini⁸, R. Gutierrez‐Quintana⁹, T. Harcourt‐Brown¹⁰, P.M. Smith¹¹, E.J. Ives¹², C. Rusbridge¹³, A. Tauro¹³, H.J. Willison²

¹Department of Veterinary Medicine, University of Cambridge, UK, ²Institute of Infection, Immunity and Inflammation, University of Glasgow, UK, ³Vet Extra Neurology, Broadleys Veterinary Hospital, Stirling, UK, ⁴Veterinary Teaching Hospital, University of Parma, Italy, ⁵Department of Clinical Science and Services, Royal Veterinary College, University of London, UK, ⁶Department of Small Animal Medicine and Clinical Biology, Ghent University, Belgium, ⁷University Clinic of Small Animals, University of Veterinary Medicine, Austria, ⁸Department of Veterinary Medical Sciences, University of Bologna, Italy, ⁹Small Animal Hospital, University of Glasgow, UK, ¹⁰Langford Veterinary Services, University of Bristol, UK, ¹¹Davies Veterinary Specialists, Higham Gobion, Herts, UK, ¹²Queen's Veterinary School Hospital, University of Cambridge, UK, ¹³Fitzpatrick Referrals, Godalming, Surrey, UK

This study was funded by PetSavers the charitable division of the BSAVA

Recent research indicated serum anti‐ganglioside antibodies as a potential marker for acute canine polyradiculoneuritis (ACP), with such antibodies reaching a sensitivity of 60% and a specificity of 97% in a small cohort of Italian dogs (n = 25). The current study aims to validate these results in a larger, geographically more heterogeneous canine population.

To date, 167 serum samples from ten institutions in four countries have been examined for antibodies against 10 common glycolipids and their heteromeric dimers with recently developed combinatorial microarrays. These comprised sera from 72 dogs with the presumptive diagnosis of ACP based on clinical and electrophysiological findings (ACP), 6 dogs in which ACP could not be excluded (possACP), 40 dogs with other peripheral and cranial neurological, neuromuscular and muscular disorders (ONM), and 49 neurologically inconspicuous dogs (CTRL).

The predominant binding pattern observed was against gangliosides GM2 and/or GA1 and their associated dimers. Overall, 48/72 ACP‐sera contained such antibodies, with 32 dogs exhibiting anti‐GM2 reactivity, 4 dogs exhibiting anti‐GA1 reactivity and 12 dogs exhibiting both. Additionally, 3/6 possACP‐dogs had anti‐GM2 or anti‐GA1 antibodies, whilst only 3/40 ONM‐ sera and 5/49 CTRL‐sera exhibited antibodies with such binding patterns. For anti‐GM2 and anti‐GA1 antibodies combined, the serum screens at this stage reached a sensitivity of 66.7% and a specificity of 88.4%. Combining groups ACP and possACP reached a sensitivity of 65.4% and a specificity of 91.0%.

These results both confirm the findings of the pilot study and indicate that this research is very likely to yield meaningful results over its time.

Stereotactic irradiation of stage IV canine nasal tumors

M. Dolera, L. Malfassi, S. Pavesi, M. Sala, G. Mazza, S. Marcarini, N. Carrara, S. Finesso

La Cittadina Fondazione Studi e Ricerche Veterinarie, Romanengo, Italy

The prognosis for canine nasal tumors with intracranial extension is poor with an expected survival of 1 month with palliation and 6.7 months with irradiation. However, studies regarding stage IV nasal tumors treated with brain‐sparing irradiation techniques are lacking. The aim of this prospective study was to evaluate feasibility and efficacy of definitive intent stereotactic radiotherapy in dogs with nasal tumors with massive intracranial extension.

Seven dogs with stage IV nasal tumors were treated with high‐dose hypo‐fractionated stereotactic radiotherapy with volumetric modulated arc therapy technique. Dose prescriptions were 32–36 Gy in four consecutive‐day fractions to the gross tumor and 30 Gy to lymphatics. Adjuvant treatment included carboplatin. Serial clinical and Computed Tomography/Magnetic Resonance Imaging examination were performed. Disease control and toxicity effects were evaluated according to response evaluation criteria in solid tumors and veterinary radiation therapy oncology group criteria. Median survival time (MST) was evaluated using Kaplan‐Meier curves.

Six carcinomas and 1 sarcoma were treated. Prescription goals were obtained in four cases with V95 > 95% and V107 > 2% whereas in 3 dogs V95 = 86–90% was accepted to limit maximum brain punctual dose < 27 Gy. Two partial response and 5 complete responses were obtained. MST was 9 months. One grade II late brain radiotoxicity and two brain ascending infections were observed. Relapse pathways involves diffuse meningeal and sphenoid invasion.

The initial experiences with the radiation therapy regimen adopted indicate a feasibility and effectiveness in modified stage IV nasal tumors. The relapse pathways observed suggests to evaluate alternative adjuvant treatment in dogs treated with stereotactic radiotherapy.

Canine peripheral nerve sheath tumors: magnetic resonance and comparison of palliation, surgery and stereotactic radiotherapy

M. Dolera, L. Malfassi, S. Pavesi, M. Sala, G. Mazza, S. Marcarini, N. Carrara, S. Finesso

La Cittadina Fondazione Studi e Ricerche Veterinarie, Romanengo, Italy

No updates for canine peripheral nerve sheaths tumor (PNST) appeared in recent literature. The aim of this study was to evaluate the correlation between clinical aspects and MRI findings of tumors involving a major peripheral nerve, plexus or root and to determine the survival time in dogs treated with palliation, surgery or stereotactic radiotherapy (SRT).

Records of dogs with PNST evaluated from 2000 to 2014 were reviewed to determine signalment, duration of clinical signs, neurological examination, MRI features, treatment option (palliation, surgery, stereotactic hypo fractionated radiotherapy). Time to first event, survival times and statistical differences across categories were calculated by the Kaplan‐Meier product limit method and log‐rank test.

Forty‐seven dogs (median age 9 years, male:female ratio 1.76) were included, with Labrador retriever over represented (17%). Roots lesions were the most frequent (46.8%), with C5‐T1, V nerve and left side more involved (25.5%, 19.1% and 61.7%). Presenting sings were lameness, paresis and pain. Mean duration of clinical signs was 90 days. MRI findings comprises increased diameter, hyper intense and contrast enhancing nerve roots (57.1%), plexus or peripheral nerve (42.9%), focal hypomiotropy and muscle hyper intensity (73%). The time to first event was 30 days after surgery and 240 days after SRT. Overall mean survival was 97, 144 and 371 days with palliation, surgery and SRT.

A predilection for Labrador retriever is observed. Comparing our results with published data, SRT seem to promise better results than palliation or surgery and warrant further evaluation.

Surgical stabilization of canine lumbosacral spine with stop‐screws and iliac wings screws

M. Dolera, L. Malfassi, S. Pavesi, M. Sala, G. Mazza, S. Marcarini, N. Carrara, S. Finesso

La Cittadina Fondazione Studi e Ricerche Veterinarie, Romanengo, Italy

Surgical stabilization of canine lumbosacral spine can be challenging. The aim of this research was to evaluate two surgical techniques to achieve lumbosacral stabilization in dogs either with normal or transitional vertebrae.

Lumbosacral instability and degenerative stenosis were evaluated by dynamic Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). In dogs with normal vertebrae two 4.5 mm screws were bicortically inserted in S1 with the heads behind the caudal articular process of L7 to prevent the extension of the lumbosacral joint; if ventral listhesis of S1 was evident, the head of the screws were augmented by methyl methacrylate. In dogs with transitional vertebrae, two 4.5 mm screws were inserted in the iliac wings, two 3.5 mm screws were inserted in the spinous process of L6 and L7; the emerging screws were embedded in methyl methacrylate after flexion of the lumbosacral spine. In cases of residual radicular compression, dorsal laminectomy and partial discectomy were accomplished. Serial clinical and imaging follow up examinations were performed.

Twenty‐two large breed dogs were enrolled. In 14 dogs stop‐screws (in 4 augmented) and in 8 dogs iliac wings screws were inserted. Two dogs required additional decompression. During a mean follow up of 36 months, clinical examination and imaging reveals amelioration of presenting complaints and reduction of radicular compression, with no surgical complications.

Stop‐screws and iliac wings technique are effective methods to obtain stabilization and indirect decompression of the lumbosacral joint. Compared with other described surgical procedures, our obtained results are better but with lesser complications.

Computational development and evaluation of a cervical intervertebral disc prosthesis in dogs by means of the finite element method

P.V.T. Marinho¹, A.P. Macedo², C.P. Sampaio³, A.C. Shimano⁴, C.C. Zani⁵, M.V.B. Arias⁵

¹Department of Surgery, University of São Paulo, Faculty of Veterinary Medicine and Animal Science, Brazil, ²Department of Dental Materials and Prosthodontics, Ribeirão Preto Dental School, University of São Paulo, São Paulo, Brazil, ³Department of Design, State University of Londrina, Brazil, ⁴Department of Biomechanics, Medicine and Locomotive Apparatus Rehabilitation, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil, ⁵Department of Veterinary Medicine, State University of Londrina, Brazil

Currently the most effective treatment of disk‐associated cervical spondylomyelopathy is distraction‐merger, however, this technique can lead to biomechanical changes in the adjacent segments increasing the risk of “domino” type injury.

The objective of this study was to develop cervical intervertebral disc prosthesis and evaluate main stress points in the prosthesis system ‐ vertebral body using the Finite Element Method (FEM). The prosthesis sizing was based on width, height and length measuring of the vertebral body of C5‐C6 of the sixteen cervical spine of mature canine cadavers weighing between 25–35 Kg. The prosthesis was developed on Rhinoceros^® software and 3D prototyping to refine its design. The analysis was done using the FEM using the Ansys Workbench^® software after applying extension, lateral and ventral bending forces, assessing the average equivalent von‐Mises stress on the prosthesis‐vertebral body system.

The vertebral body received much lower stress than the prosthesis for all applied forces. The average stresses on the vertebral body were superior on the lateral and ventral surfaces when compared to the cranial surface of C5 and the caudal of C6. Finally, the average stress on the prostheses was intensely more focused on the bearing contact surface and less intensely on the interface between the prosthesis and screw. For screws, the bigger stress happened on the cranial surface.

The developed prosthesis had an adequate design and good fit on the intervertebral space between C5 and C6, allowing a homogeneous distribution of stresses on vertebral body, which lowered stress on vertebral endplates.

Changes in interictal vs. postictal diffusion and perfusion MR parameters in familial spontaneous epileptic cats

D. Hasegawa, S. Mizoguchi, Y. Hamamoto, T. Kuwabara, Y. Yu, A. Fujiwara, M. Fujita

Department Clinical Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan

Familial spontaneous epileptic cats (FSECs) is the only genetic model of epilepsy in cats. The epileptogenic zone of FSECs is thought to exist in the amygdala and/or hippocampus, as determined by seizure semiology (spontaneous orofacial automatisms and stimulation‐induced generalized seizures), EEG features, and volumetric MRI.

To confirm and analyze their epileptogenic zone, we performed diffusion and perfusion MRI. This study was approved by the Animal Care and Use Committee of the University. Using a 3.0T MRI system, diffusion‐weighted imaging, diffusion tensor imaging, and dynamic susceptibility contrast perfusion weighted imaging were performed, and the apparent diffusion coefficient (ADC), fractional anisotropy, relative cerebral blood flow (rCBV), relative cerebral flow (rCBF), and mean transit time were calculated. Six healthy control cats and 6 FSECs at the interictal state were compared. Compared with controls, ADCs in the hippocampus of FSECs were significantly higher and rCBV and rCBF in the hippocampus of FSECs were significantly lower than in the controls. Using the same 6 FSECs, diffusion and perfusion parameters were compared between the interictal and postictal states. Images of the postictal state were obtained immediately after vestibular stimulation‐induced seizures (<15 min). At the postictal state compared with the interictal state, ADCs in the hippocampus were significantly decreased and rCBV and rCBF in the amygdala and cortex were significantly increased.

In conclusion, FSECs have higher diffusion and lower perfusion in the amygdala or hippocampus at the interictal state; in turn, these are reversed at the postictal state, as observed in PET/SPECT studies of human epilepsy.

Post mortem assessment of intervertebral disk protrusion in dogs without neurological signs

C.C. Zani¹, M.V.B. Arias¹, P.V.T. Marinho², G.A.C. Diamante¹

¹Department of Veterinary Clinics, Londrina State University, Brazil, ²Department of Surgery, University of Sao Paulo, Faculty of Veterinary Medicine and Animal Science, Brazil

Hansen type II intervertebral disc degeneration (IVD) is a process that increases with age, but link between disc degeneration, protrusion with spinal cord compression and clinical signs remain unclear.

Our objective was to determine the presence of type II disk degeneration with extradural spinal cord compression in 30 dogs (24 nonchondrodystrophic, 6 chondrodystrophic) without neurological signs, aged more than 7 years old (median 10), weighing from 6 to 36 kg (median 12.9 kg). Dogs were euthanized for non‐neurological reasons and owners gave permission to the study. Immediately after euthanasia, myelography was performed in order to identify sites of disc protrusion. All spines were opened by dorsal laminectomy to identify all sites of protrusion, identified or not by myelography. Protruded disc was opened in a midsagittal plane in order to perform macroscopic classification of IVD according to Thompson (1990) scheme (I‐healthy to V‐severe degeneration).

We observed that 12/30 dogs (40%) presented disc protrusion, and from these, seven (58%) had more than one (maximum 5) intervertebral disc protrusion. Five dogs were chondrodystrophic (83%) and seven nonchondrodystrophic (29%). The most affected site was L4‐L5 (6 discs), followed by L6‐L7 region (3 discs), C6‐C7 (3 discs), and T2‐T3 (1 disc). Grade III IVD was the most common (14 discs), followed by grade IV, V (4 discs) and II (3 discs).

Nonchondrodystrophic and chondrodystrophic old dogs may have disk asymptomatic protrusion and spinal cord compression representing a normal aging process, being important to take this in consideration when dealing with old dogs with neurological signs.

The occurrence of cardiac abnormalites in canine steroid responsive meningio‐arteritis (SRMA)

G. McLauchlan¹, J. Penderis², L. Dickson¹, K. Holmes¹, J. Prieto‐Ramos¹, L. Cosgrove¹, R. Gutierrez‐Quintana¹, J. Guevar¹, I. Sanz‐Gonzalez¹, A. French¹

¹Small Animal Hospital, School of Veterinary Medicine, University of Glasgow, UK, ²Vet Extra Neurology, Stirling, UK

Concurrent cardiac disorders, such as arrhythmias and myocarditis, are well documented in human patients with central nervous system (CNS) diseases, including bacterial meningitis. Similarly, single case reports in dogs with steroid responsive meningio‐arteritis (SRMA) have suggested concurrent cardiac abnormalities. This prospective study aimed to document the prevalence of cardiac changes in dogs with SRMA based on measurement of serum cardiac troponin‐I (cTnI) and echocardiography, and to monitor these changes during SRMA treatment.

SRMA was diagnosed based on typical clinical presentation, blood/urinalysis, cerebral spinal fluid analysis, and in some cases infectious disease serology and MRI. Echocardiography was performed in all dogs, where possible prior to starting any anesthesia, opiate or glucocorticoid therapy. Repeated neurological examination, C‐reactive protein (CRP), cTnI and echocardiography were performed after 14 days.

Fourteen dogs were prospectively enrolled (3FE, 1FN, 5ME, 5MN) with a mean age of 12.5 months (range 6 months – 30 months). Increased cTnI was identified in 5/14 dogs (mean 4.16 ng/l; range 0.59–14.5; reference range <0.15) and echocardiographic abnormalities detected in 12/14 dogs, including spontaneous echo‐contrast (SEC) in 12/14 and mild pericardial effusion in 5/14.

Treatment with glucocorticoids was associated with clinical improvement and CRP normalization in all dogs. cTnI normalized in 4/5 dogs and significantly reduced in 1/5 dogs. SEC resolved in 9/12 dogs and reduced in 3/12 dogs. Pericardial effusion resolved in all dogs.

These results show that cardiac changes are common in dogs with SRMA, and resolve with therapy in most dogs. Longer term follow‐up of dogs with persistent cardiac changes is warranted.

Comparison of clinical presentation and outcome in dogs with presumptive ischaemic myelopathy and acute non‐compressive nucleus pulposus extrusion

J. Fenn, R. Drees, H.A. Volk, S. De Decker

Department of Clinical Science and Services, Royal Veterinary College, Hatfield, UK

The objective of this study was to compare the clinical presentation and outcome of dogs with a presumptive diagnosis of ischemic myelopathy (IM) and acute non‐compressive nucleus pulposus extrusion (ANNPE).

Medical records and MRI studies were reviewed, yielding 93 suitable dogs with an antemortem presumptive diagnosis of IM or ANNPE. Patient signalment, clinical presentation and short‐term outcome were retrospectively retrieved from clinical records. Long‐term follow‐up was achieved by telephone questionnaire with veterinarians and owners.

Compared to the hospital population of the study institution, English Staffordshire Bull Terriers were overrepresented with IM, and Border Collies with ANNPE. Dogs with ANNPE were significantly older (mean 7.0y ±2.2) than those with IM (mean 5.9y ±2.8). Dogs diagnosed with ANNPE were significantly more likely to present with a history of onset vocalization (50%), spinal hyperesthesia (47.6%) and a C1‐C5 myelopathy (16.7%) compared to those with IM. Dogs with IM were more likely to present with an L4‐S3 myelopathy (11.8%), compared to dogs with ANNPE (0%). Dogs with ANNPE were more likely to be ambulatory at discharge (69.0%) than those with IM (43.1%). Although long‐term follow‐up did not reveal a difference in quality of life or outcome success, dogs with IM were significantly more likely to have reduced fecal continence (40.7%), compared to those with ANNPE (7.7%).

In conclusion, differences were found in clinical presentation that may aid differentiation between IM and ANNPE. ANNPE may lead to a faster recovery of function, and dogs with IM may be at higher risk of permanent fecal incontinence.

Is the neurological examination a valid method to correctly identify the lesion localization of vestibular dysfunction in dogs?

U. Bongartz^1,2, J. Neßler¹, A. Maiolini¹, V.M. Stein¹, A. Tipold¹, A. Bathen‐Nöthen²

¹Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Germany, ²Veterinary Practice A. Bathen‐Nöthen, Cologne, Germany

The aim of this study was to prove the reliability of the neurological examination in localizing a vestibular syndrome in dogs with magnetic resonance imaging (MRI) as gold standard of correct lesion localization. Neurological examination results and MRI findings of 91 dogs with vestibular signs were reviewed retrospectively encompassing central vestibular syndrome (CVS) and peripheral vestibular syndrome not responding to treatment (PVS).

The majority of dogs (78/91; 85.7%) showed a head tilt as cardinal sign indicating vestibular disease. Additional signs comprised ataxia, strabismus, nystagmus, proprioceptive deficits, other cranial nerve deficits, and tetraparesis. Based on the neurological examination, 31 dogs had PVS, 57 had CVS and 3 remained unclear. After MRI examination 20 dogs had PVS, 70 dogs had CVS, and the diagnosis remained unclear in one dog. The neuroanatomical localization after neurological examination was in accordance with MRI results in 80.6% (54/67) for CVS and 85% (17/20) for PVS. After MRI and cerebrospinal fluid analysis clinical diagnoses of inflammation (21/70; 30%), neoplasia (16/70; 22.9%) and infarcts (10/70; 14.3%) were assessed as causes for CVS and idiopathic (12/20; 60%) and otitis media/interna (6/20; 30%) for PVS.

In contrast to other studies, CVS occurred more frequently than PVS in the current study referring to the fact that only dogs with severe PVS not responding to the first treatment attempt underwent a complete diagnostic workup including MRI. Despite this bias the neurological examination is still a valid method for identifying the correct localization in dogs with vestibular dysfunction.

Evaluation of postoperative survival and complications after intracranial surgery in dogs

A.K. Forward, H.A. Volk, S. De Decker

Royal Veterinary College, University of London, Hatfield, UK

Although intracranial surgery is increasingly performed in veterinary medicine, little is known about the nature and prevalence of post‐operative complications and survival of dogs undergoing intracranial surgery. This study aimed to describe survival and early postoperative outcome following intracranial surgery in dogs.

Records were searched and analyzed for dogs that had intracranial surgery performed between 2005–2015. Signalment, clinical presentation, neurological deficits, concurrent medical conditions, perioperative laboratory data, diagnosis, administration of perioperative glucocorticoids or anti‐epileptic drugs and specific imaging, surgical and anesthetic variables were evaluated as potential risk factors for survival, occurrence of postoperative complications and hospitalization times. Univariate linear and logistic regression followed by multivariable regression models were performed.

Fifty dogs were included. 96% (48/50) of dogs survived the immediate postoperative period, 92% (46/50) survived to discharge and 48% (23/48) experienced a postoperative complication. Non‐neurological post‐operative complications were seen in 19% (9/48) of dogs, with aspiration pneumonia being the most common one [12% (5/48)]. Early postoperative neurological deterioration was seen in 46% (22/48) of dogs, with this group more likely to develop non‐neurological postoperative complications. Development of non‐neurological complications (P = 0.0004) and higher postoperative serum glucose concentrations (P = 0.002) were associated with longer hospitalization times. Higher postoperative lactate concentrations (P = 0.009) were associated with longer hospitalization times in the ICU.

Dogs undergoing intracranial surgery had a high rate of survival with a relative low number of postoperative complications. As a result, intracranial surgery for appropriate cases can offer a good outcome for dogs but more investigation is needed to ascertain long‐term survival times.

Magnetic resonance features of suspected leukoaraiosis in elderly dogs

E. Scarpante, G.B. Cherubini, A. de Stefani, O. Taeymans

Dick White Referrals, Six Mile Bottom, UK

Age‐related changes have been identified on brain MRI (magnetic resonance imaging) of dogs over 9 years of age. Brain atrophy, ventricular enlargement, and well‐demarcated sulci have been already described in veterinary medicine.

This case series describes the MRI features of suspected leukoaraiosis in 7 elderly dogs.

The clinical database between October 2009 and May 2015 was reviewed. Dogs with bilaterally symmetrical periventricular areas of T2 and FLAIR hyperintensity compatible with leukoaraiosis and older than 9 years were included. Seven dogs met the inclusion criteria, two neutered females and five neutered males, mean age was 13 years 5 months. Breeds included two Jack Russell Terrier, two cross breed, and one of each of the following breeds: Labrador retriever, Lhasa apso and Cavalier King Charles Spaniel. All dogs underwent MRI of the brain for a suspected intracranial disease based on physical and neurological examinations.

The T2 and FLAIR hyperintensities appeared as well‐defined bilaterally symmetrical periventricular areas of increased signal intensity, located dorso‐laterally and dorso‐caudally to the lateral ventricles, isointense to normal white matter on T1‐weighted images and non‐contrast‐enhancing. Given their topographical distribution these lesions were considered most compatible with an age‐related white matter change.

Pathophysiology of leukoaraiosis remains incompletely understood, but an ischemic origin of these lesions has been favored. Endothelial damage, leading to narrowing of the vessels lumen, and ultimately reduced blood flow, is suspected. The pattern of vascularization, which makes the periventricular white matter an arterial border zone, has been considered responsible for the topographical distribution typical of these lesions.

Prevalence and breed predisposition of thoracolumbar intervertebral disc disease in cats

S. De Decker, A.S. Warner, H.A. Volk

The Royal Veterinary College, University of London, Hatfield, UK

Although several studies have evaluated the prevalence and breed predisposition of intervertebral disk disease (IVDD) in dogs, such information is not yet available for cats. The aims of this study were to evaluate the prevalence and possible breed predilections for thoracolumbar IVDD in cats.

Medical records and imaging studies of cats diagnosed with IVDD were retrospectively reviewed and compared to the general hospital population between January 2008 and August 2014. The association between type of IVDD [i.e. nucleus pulposus extrusion (NPE) or anulus fibrosus protrusion (AFP)] and breed, age, gender, duration and severity of clinical signs was also evaluated.

Of 12900 cats presented during the study period, 31 (0.24%) were diagnosed with IVDD, including 17 purebred and 14 non‐purebred cats. Of all presented purebred cats, 2.84% were diagnosed with IVDD. More specifically, 1.29% of all British Shorthairs and 1.83% of Persians were diagnosed with IVDD. Compared to the general hospital population, purebred cats (P < 0.0001), British Shorthairs (P < 0.0001) and Persians (P = 0.0006) were significantly overrepresented with thoracolumbar IVDD. Of 31 cats with IVDD, 19 were diagnosed with NPE and 12 with AFP. Cats with NPE had a significantly shorter duration of clinical signs (P = 0.0002) and demonstrated more severe neurological deficits (P = 0.04) compared to cats with AFP.

Although IVDD is an uncommon condition in cats, purebred cats, British Shorthairs, and Persians were overrepresented. It is currently unclear if this represents a true breed predisposition or a higher likelihood of owners of purebred cats to seek referral for advanced diagnostic imaging procedures.

Comparison of cervical canal occupancy in giant, large, and small breed dogs: an MRI morphometric study

M. Bonelli^1,2, R. da Costa²

¹Federal Rural University of Pernambuco, Recife‐PE, Brazil, ²The Ohio State University, Columbus‐OH, USA

The pathophysiology of cervical spondylomyelopathy (CSM) appears to involve a major static component, namely relative and absolute stenosis of the vertebral canal, which would facilitate or cause compression of the spinal cord.

Our objective was to compare the cervical vertebral canal occupying ratio of the spinal cord (C3‐C7) in giant, large, and small breeds hoping to gain insights regarding the prevalence of CSM in larger breed dogs compared to small breeds. Magnetic resonance images for 90 dogs were used: 30 small‐breed dogs; 30 Doberman Pinschers (15 clinically normal and 15 CSM‐affected) representing large‐breed dogs; and 30 Great Danes (15 clinically normal and 15 CSM‐affected) representing giant‐breed dogs. Area and height of the spinal cord and vertebral canal/foramina between C3 and C7 were measured on transverse and sagittal images, respectively, at both the cranial and caudal edge of the vertebrae. Calculations were made to determine the vertebral canal occupying ratio of the spinal cord (cord:canal ratio) for each group.

Overall, small‐breed dogs had higher cord:canal area and height ratios, suggesting they have less space available for the spinal cord. Great Danes had the lower cord:canal area ratios, indicating they have less area of the canal occupied by the spinal cord. Doberman Pinschers generally had similar values of cord:canal area ratios to the small‐breed dogs.

Our results suggest that the vertebral canal occupying ratio of the spinal cord cannot, by itself, explain the discrepancy in prevalence of CSM in small and large breeds.

Non accidental trauma (inflicted brain injury)

C. Centellas¹, X. Raurell¹, G. Feliz¹, A. Zamora²

¹Hospital Veterinari Molins, Barcelona, Spain, ²Imagovet, Barcelona, Spain

Non accidental trauma (NAT) synonyms like non accidental injury (NAI); shaken baby syndrome (SBS) or non accidenteal head injury (NAHI) are often used in human medicine to describe inflicted brain injury (iBI).

Three cases with clear evidence of iBI were detected at our Hospital in a two month period. Their histories and subsequent outcomes demonstrated human involvement. All of them undergo MR (Esaote 0.25T) which was revealed as one of the best diagnostic clue to detect animal abuse. MRI is more difficult to perform in acute setting than computed tomography (CT). However, overall increased sensitivity for most injuries except fractures and acute hemorrhages outweigh difficulties. It may be also helpful as an adjunct for the evaluation of axonal shear injuries and for more precise dating of intracranial hemorrhage. Diffusion‐weighted imaging (DWI) could also detect early ischemic injury and is frequently used in trauma to help determine prognosis.

In the first case, MR findings were compatible with the SBS (medical terminology); subdural hemorrhage (SDH) over cerebral convexities and interhemispheric fissure which is the most common manifestation in NAT. The second patient showed also subdural collections at the temporoparietal convexities, occipital contusion and zygomatic arch fracture. The third one presented residual encephalomalacic lesions and a frontoparietal bone defect. Multi‐organ system trauma was also found; rib fractures, vitreous hemorrhage, a foreign body in the uterus and perineal burns.

We have not found many veterinary bibliographies on this subject whereas there areextensive studies in human medicine. Making a correct diagnosis could be crucial to the health and welfare of the animals and the family members involved.

Retrospective study of spinal arachnoid diverticulum in 15 dogs diagnosed with 3D‐CISS MRI

A. Tauro¹, J. Jovanovik¹, C. Driver¹, C. Rusbridge^1,2

¹Fitzpatrick Referrals, Godalming, Surrey, UK, ²University of Surrey, Guildford, UK

Spinal arachnoid diverticula (SAD) are considered rare conditions in veterinary medicine, although the number of diagnosed cases is recently growing due to the increase use of MR imaging and predisposed breed popularity. SAD are defined as intradural, extramedullary cavitations filled with CSF; the etiology is not well understood and disorders that cause alterations of the arachnoid trabeculae and interference with the CSF flow are implicated. A better outcome is based on an early diagnosis and intervention, and the interpretation of the advanced images can be challenging often leading to misdiagnosis and treatment delay.

The purpose of this retrospective study was to describe a three‐dimensional (3D) constructive interference in steady state (CISS), which has a combination of high signal levels and extremely high spatial resolution and offers excellent contrast between CSF and pathological structures in providing anatomical information to identify SAD with minimal signal loss due to CSF pulsations.

Medical records of 15 dogs between 2013 and 2015 were reviewed retrospectively. Inclusion criteria were the presence of compatible clinical signs and advance imaging using the 3D‐CISS sequences confirming the presence of SAD. Male Pugs were over‐represented, while caudal thoracic SAD were outnumbered. Pugs appeared to be predisposed to multiple SAD located dorsally at C2‐C3 and thoracic spine. 3D‐CISS sequences were beneficial in detecting SAD secondary to scarring and adhesion following surgical intervention.

Findings from this study support the superiority of 3‐D CISS imaging in all cases particularly when spinal cord edema, gliosis and/or syringomyelia may obscure the true spinal cord lesion.

Clinical features and disease progression of L‐2‐hydroxyglutaric aciduria in 27 staffordshire bull terriers

A. Shea¹, L. De Risio¹, H. Carruthers², E. Beltran³

¹Centre for Small Animal Studies, The Animal Health Trust, Newmarket, UK, ²Tay Valley Veterinary Centre, Perth, Scotland, ³The Royal Veterinary College, University of London, Hatfield, UK

L‐2‐hydroxyglutaric aciduria (L2HGA) results from autosomal recessive mutations within the L‐2‐hydroxyglutarate dehydrogenase (L2HGDH) gene. Accumulation of L‐2‐hydroxyglutaric acid in brain tissue causes oxidative stress and interferes with cerebellar creatine kinase activity. There is no published data on clinical outcomes or prognostic factors. Our aim was to describe the onset, pattern and nature of clinical signs (CS) in a cohort of L‐2‐HGA‐affected Staffordshire Bull Terriers (SBTs).

Owners of 119 SBTs positive for the L2HGDH genetic mutation were requested to complete a questionnaire regarding their pet's symptoms. Information was available for 27 dogs, all with neurological abnormalities. The mean age of onset of CS was 12 months (range 2.5–60). Gait dysfunction was reported in all 26 dogs with available data, with stiffness of all four limbs the most common (24/26) and earliest recognized abnormality. Kyphosis (19/26), body and/or head tremors (19/26) and hypermetria (15/26) were frequent. Behavioural changes were present in 24/27 dogs; most commonly staring into space (21/27), signs of dementia (15/27) and loss of training (15/27). Fifteen dogs demonstrated paroxysmal seizure‐like or dyskinetic episodes. Nineteen (70%) dogs were alive at a mean of 76.6 months (12–170) after onset of CS; eight were ≥99 months from onset. L2HGA was the cause of euthanasia in six dogs with meningoencephalomyelitis and suspected stroke resulting in euthanasia of two dogs. Euthanasia occurred at a mean of 44 months (8.5–93) after onset of CS, with 2/8 dogs euthanized within 12 months.

L‐2‐HGA is considered a progressive neurological disease, however symptoms can be successfully managed to allow dogs a good quality of life long term.

Identification of the causal GFAP mutation in a labrador retriever with Alexander's disease

V. Martlé¹, M. Van Poucke², L. Van Brantegem³, L. Van Ham¹, S. Bhatti¹, R. Ducatelle³, L. Peelman²

¹Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Belgium, ²Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Belgium, ³Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Belgium

Alexander's disease is a neurodegenerative disorder of astrocyte dysfunction in humans, for which already a number of causal mutations have been described, mostly de novo dominant missense mutations in the Glial Fibrillary Acidic Protein (GFAP). A similar frequently lethal disorder was already phenotypically described in 12 dogs and 4 sheep, but until now no causal mutations have been identified.

A 3‐month‐old Labrador retriever pup developed progressively worsening tetraparesis with a spastic swimming‐puppy‐like position of the thoracic limbs. One month later mild vestibular signs and myoclonic jerks were noticed. Complete blood work, electrophysiological examination and CSF were within normal limits. The pup was euthanized at the age of 4.5 months and on histopathological examination Alexander's disease was diagnosed by the detection of GFAP containing Rosenthal fibers in astrocytes throughout the brain and spinal cord. From frozen brain tissue, the complete GFAP coding sequence was amplified by (RT)‐PCR, sequenced and compared to the canine reference sequence. Genetic examination of the GFAP gene identified a heterozygous G→A nucleotide substitution resulting in an arginine to histidine amino acid substitution at position 240.

We detected a causal point mutation in a Labrador retriever with multifocal central nervous system signs and characteristic histopathological features of Alexander's disease. This is an orthologous mutation to the heterozygous de novo dominant R239H hotspot mutation in humans. To the best of our knowledge, this is the first report of a GFAP mutation in an animal with Alexander's disease.

Paroxysmal dyskinesia in adult maltese dogs?

V. Martlé¹, S. Bhatti¹, D. O'Brien², I. Gielen³, L. Van Ham¹

¹Department of Small Animal Medicine and Clinical Biology, Ghent University, Merelbeke, Belgium, ²College of Veterinary Medicine, University of Missouri‐Columbia, Columbia, USA, ³Department of veterinary Medical Imaging and Small Animal Orthopaedics, Ghent University, Merelbeke, Belgium

Paroxysmal dyskinesias (PD) are central nervous system disorders characterized by episodes of abnormal involuntary hyperkinetic movement or muscle tone without altered consciousness. Hereditary canine PD have been described in Chinooks, Soft Coated Wheaten terriers, Scottish terriers and Cavalier King Charles Spaniels.

This study provides the phenotypical description of a possible PD observed in 5 adult Maltese dogs. The episodes always started at the age of 5 to 6 years and dogs appeared normal in between. In four dogs, the episodes were witnessed by video analysis and in one dog an episode occurred during consultation. Episodes seemed to be triggered by exercise, stress or excitement and were typically characterized by generalized stiffness of the limbs and alternating involuntary flexion of 1 or multiple limbs. Often a kyphotic back posture was also noticed. All dogs remained fully conscious during the episodes, but seemed uncomfortable. The frequency and duration of the dyskinesia episodes varied between dogs. The clinical and neurological examination (3 dogs) and further diagnostic work‐up (complete blood work (3 dogs), MRI brain and CSF analysis (2 dogs), electrophysiological exam (1 dog), urinalysis (1 dog) were unremarkable. Three dogs were clear of the PIGN missense mutation recently discovered in Soft Coated Wheaten terriers with PD. Therapy with acetazolamide (2 dogs) provided an obvious improvement in 1 dog.

A possible paroxysmal dyskinesia with an adult onset is suspected in the Maltese dog, although additional cases and expanding pedigree and genetic analysis is necessary.

Application of magnetic resonance spectroscopy in canine epilepsy of unknown origin – the preliminary results

A. Olszewska¹, M. Płonek¹, J. Nicpoń², M. Wrzosek¹

¹Department of Internal Medicine and Clinic of Diseases of Horses, Dogs and Cats, Wrocław University of Environmental and Life Sciences, Wroclaw, Poland, ²Center of Experimental Diagnostics and Innovative Biomedical Technology, The Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, Wroclaw, Poland

Canine epilepsy posts a diagnostic challenge for veterinary professionals. Magnetic resonance spectroscopy (MRS) is a noninvasive method that determines the chemical composition of brain tissue and is displayed as a spectrum of peaks fit along the x‐axis, labeled in parts per million (ppm). The three major peaks observed in the MRS spectra are those of N‐acetyl‐aspartate (NAA), creatine (Cr), choline (Cho). MRS may be used to lateralize an epileptic focus.

The study was carried out on 10 dogs of different breeds with a diagnosis of canine epilepsy of unknown origin, which underwent an MRI examination utilizing a 1.5T Ingenia Philips scanner under general anesthesia. MRS was performed using single‐voxel 1 cm × 1 cm × 1 cm acquisitions. The voxel was located bi‐hemispherically at the border of the piriform lobe and hippocampus. Three main metabolites (NAA, Cho, Cr) were determined in the analysis and compared between hemispheres.

There was an interhemispheric difference in the NAA to Cr ratios in 6 of the 10 dogs. Four dogs presented a normal NAA/Cr ratio. The proportions of Cho/Cr were stable in all 10 dogs. The observed difference in the ratio of NAA/Cr between patients may have been due to various epileptic stages of the dogs during the study.

These preliminary results suggest the possible application of MRS to determine the lateralization of seizure foci in canine epileptic patients. NAA may be used as an indicator of neuronal dysfunction during seizures.

Relapses in dogs with steroid‐responsive meningitis‐arteritis

E. Biedermann¹, A. Tipold², T. Flegel¹

¹Department of Small Animal Medicine, University of Leipzig, Leipzig, Germany, ²Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany

The purpose of this study was to describe relapse rates in dogs with steroid‐responsive meningitis‐arteritis (SRMA) and, in addition, to identify factors influencing the occurrence of relapses.

Dogs with SRMA were retrospectively identified from the hospital database and were assigned to one of three groups: dogs without relapse, with at least one relapse and unknown relapse‐status. The groups without and with at least one relapse were compared regarding the following parameters: sex, age, body weight, nucleated cell count, total protein concentration, and percentage of neutrophils on initial cerebrospinal fluid (CSF) analysis, IgA in serum and CSF initially, nucleated cell count on CSF analysis at 3‐month‐re‐evaluation, C‐reactive protein (CRP) in serum and CSF initially and at 3‐month‐re‐evaluation, frequency of breeds.

Between one and four relapses were seen in 32.4% of dogs whereas 55.4% were relapse free. The relapse status was unknown in 12.2% of dogs. None of the factors tested were different between dogs with and without relapse, except for the following three: 1. Nucleated cell count in CSF at 3‐month‐re‐evaluation was higher in dogs with relapses. 2. Beagles are more frequently affected by relapses. 3. There was a tendency for higher CRP levels in serum in dogs with relapse at 3‐month‐re‐evaluation.

We conclude that relapses are frequent but there is currently no reliable indicator predicting relapses. Elevated CRP in serum on re‐evaluation, however, warrants continuing therapy.

A mutation in MFSD8 causes neuronal ceroid lipofuscinoses in Chihuahua dogs

K.M.E. Faller¹, J. Bras², S. Sharpe¹, L. Darwent², C. Kun‐ Rodrigues², J. Alroy³, J. Penderis⁴, S. E. Mole⁵, R. Gutierrez‐Quintana¹, R. J. Guerreiro²

¹School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK, ²Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK, ³Department of Pathology, Tufts University School of Medicine and Tufts‐New England Medical Center, Boston, USA, ⁴VetExtra Neurology, Stirling, UK, ⁵MRC Laboratory for Molecular Cell Biology, University College London, London, UK

Two littermates Chihuahua dogs (one male, one female) were investigated for progressive blindness, ataxia and cognitive impairment with an onset from around one year of age. Magnetic resonance imaging revealed marked generalized brain atrophy suggestive of a neurodegenerative disorder. Due to worsening of the signs, both dogs were euthanized before the age of two years. Brain histopathological examination demonstrated abundant neuronal accumulation of autofluorescent intracytoplasmic storage material characteristic of Neuronal Ceroid Lipofuscinosis (NCL), with a lamellar ultrastructure.

Following ethical approval, DNA was collected from both affected dogs and five related dogs including the sire and dam. Whole genome sequencing was performed on one of the affected dogs. Sequence alignment and variant calling was done against the canine reference genome. Homozygous variants were found in the coding or splicing regions of four genes previously identified as causing NCL (ARSG, CLN2 = TPP1, CLN6, CLN7 = MFSD8). Segregation analysis by Sanger sequencing characterized MFSD8:c.843delT ‐ predicted to cause a truncated protein ‐ as the causal mutation.

Although NCL has been previously reported in Chihuahuas on three different occasions, the causal mutation had remained unknown. In a recent report, the identical mutation uncovered in this study was strongly suspected to be the cause of disease in a single case in the Chinese Crested dog, suggesting a genetic relationship between both breeds. Considering the strong similarity of the clinical presentation and histological changes between humans with CLN7 disease and the two dogs presented here, Chihuahua could potentially be used as a large animal model of the human disease.

Lafora disease in a beagle

I. Hajek¹, V. Simerdova², P. Wang³, S.F.M. Bhatti⁴, B.A. Minassian⁵, V. Palus¹

¹Centre of Veterinary Medicine Sibra, Bratislava, Slovakia, ²Small Animal Clinic, Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences Brno, Brno, Czech Republic, ³Program in Genetics and Genome Biology, Hospital for Sick Children and University of Toronto, Toronto, Canada, ⁴Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium, ⁵Department of Paediatrics, Faculty of Medicine, University of Toronto, Toronto, Canada

Lafora disease, also called progressive myoclonic epilepsy, is a fatal inherited neurodegenerative disease caused by deposits of inclusion bodies within the cells of several organs including the brain. There is a known genetic mutation in the wire‐haired dachshunds but a genetic mutation has not yet been identified in different dog breeds.

This case report describes the mutation in a clinically affected beagle. An eight‐year‐old neutered male beagle with progressive myoclonic episodes was presented for neurological examination. We observed mild myoclonic movements of the head exacerbated by sudden sounds. A routine hematology, biochemistry and urinalysis were unremarkable. Magnetic resonance of the brain and cerebrospinal fluid examination were unremarkable. Southern blot analysis of genomic DNA from the patient´s blood collected in EDTA tube detected a sequence repeat for an EPM2B gene.

In conclusion, this is the first report of an EPM2B mutation causing progressive myoclonic epilepsy in a beagle dog breed. This case report suggests that the similar mutations can be present also in other breeds suffering of progressive myoclonic epilepsy.

Expression of epidermal growth factor receptor and KI‐67 in canine gliomas

A. Fraser¹, B. Bacci², M. le Chevoir¹, S. Long¹

¹Translational Research and Animal Clinical Trial Studies Group, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Victoria, Australia, ²Department of Anatomic Pathology, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Victoria, Australia

The histologic classification of gliomas can be challenging. In people accurate diagnosis is essential as the treatment and prognosis varies between tumor type and grade. Numerous biomarkers have been investigated in human gliomas to aid in their diagnosis and to act as potential therapeutic targets. To utilize these therapies in veterinary medicine investigation of biomarkers in canine gliomas is required. Epidermal growth factor receptor (EGFR) is associated with glioma grade and is a therapeutic target in human glioma trials. The Ki‐67 labeling index (LI) is a marker of proliferation, which is a prognostic indicator in human gliomas.

The objectives of the current study were to evaluate EGFR and Ki‐67 expression immunohistochemically in canine gliomas and to determine if immunopositivity is associated with histologic tumor type and grade.

Formalin‐fixed paraffin‐embedded canine gliomas were assessed for EGFR and Ki‐67 expression. EGFR immunopositivity was evaluated using a semi‐quantitative score and the Ki‐67 LI was calculated.

Thirty‐one canine gliomas were evaluated. EGFR expression was identified in 16/31 (51.6%) tumors; expression was significantly greater in high grade tumors when compared to low grade tumors (P = 0.041). EGFR expression was also significant in gliomatosis cerebri. Ki‐67 was expressed in 28/31 (90.3%) gliomas and the Ki‐67 LI was significantly greater in the high grade tumors (P = 0.024). A significant moderate correlation was identified between EGFR immunopositivity and Ki‐67 LI (r = 0.472, P = 0.007).

While EGFR is expressed in approximately 50% of canine gliomas, investigation in to other therapeutic targets is required. EGFR may be a suitable therapeutic target for gliomatosis cerebri.

Identification of motor patterns and assessment of primitive reflexes in canine neonates

C. Morales¹, J. Fatjó², V. Aige³, P. Montoliu¹

¹Neurocat Veterinaris, Barcelona, Spain, ²Chair Affinity Foundation Animals and Health, Department of Psychiatry and Forensic Medicine, School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain, ³Departament de Sanitat i Anatomia Animals, Universitat Autònoma de Barcelona, Barcelona, Spain

Primitive reflexes are brainstem‐mediated, complex, automatic and stereotyped movement patterns that appear during development. They are usually present at birth and become more difficult to elicit with central nervous system maturation or are replaced by more complex postural responses. The early motor behaviour of the newborn is related to primitive reflexes. Descriptions of primitive reflexes in dogs are sparse, and their influence on neurological examination is poorly documented.

The purpose of this study was to describe in detail the main primitive reflexes that can be assessed in canine neonates and how these motor patterns influence neurological examination. This is part of a larger study with the objective to develop a neurological examination procedure for neonatal dogs. This study obtained ethical approval.

Serial neurologic examinations were performed in 110 pups ranging from 0 to 13 days of age and of different breeds, mainly beagles. Assessed items included primitive reflexes and responses described in previous studies, human primitive reflexes adapted for evaluation in dogs and observation of characteristic motor patterns. A total of 13 primitive reflexes were evaluated.

It was possible to elicit righting, withdrawal and crossed extensor reflexes, walking reflex, hopping, and pelvic limb straightening‐supporting reflex from birth in most dogs, and uniform and reproducible responses were observed. For all these reflexes, detailed descriptions of initial posture, stimulus, supporting maneuvers, and a gradation of normal responses were established. Influences of instinctive motor patterns and optimal behavioural states for each item were identified. This work establishes a basis for standardization of canine neonates neurological assessment.

Prognostic factors for one week survival in dogs diagnosed with meningoencephalitis of unknown aetiology

I. Cornelis, H.A. Volk, S. De Decker

Clinical Science and Services, The Royal Veterinary College, Hatfield, UK

Although several studies have evaluated the long‐term outcome of meningoencephalitis of unknown etiology (MUA), little is known about short‐term survival and initial response to therapy. The aims of this study were therefore to evaluate possible prognostic factors for 7‐day survival after diagnosis of MUA.

Medical records were reviewed for dogs diagnosed with MUA between 2004 and 2015. Previously described inclusion criteria were used, and for all dogs 7‐day survival data needed to be available. A poor outcome was defined as death.

One hundred and sixteen dogs met the inclusion criteria. Thirty‐two (38%) dogs died within 7 days after making a presumptive diagnosis of MUA. Dogs were typically treated with steroids and/or cytosine arabinoside. Both the presence of seizures and the presence of cluster seizures were significantly associated with a poor outcome. Total nucleated cell count in cerebrospinal fluid and lactate levels on venous blood analysis at time of diagnosis were significantly associated with poor outcome. Age, sex, neuroanatomical localization(s), total protein concentration in cerebrospinal fluid, and white blood cell count were not associated with 7‐day survival.

Every third dog died within one week after diagnosis, emphasizing the need for evaluation of short‐term prognostic factors. Presence of seizures and presence of cluster seizures at time of presentation, increased venous lactate concentrations and a higher total nucleated cell count in the cerebrospinal fluid are significantly associated with 7‐day survival.

Anticonvulsant hypersensitivity syndrome in a dog after phenobarbital administration

L. Bosseler¹, I. Cornelis^2,3, P. Defauw², S. Bhatti², R. Ducatelle¹

¹Department of Pathology, Bacteriology and Avian Medicine, Faculty of Veterinary Medicine, Ghent University, Belgium. ³Clinical Science and Services, The Royal Veterinary College, Hatfield, UK, ²Department of Medicine and Clinical Biology of Small Animals, Faculty of Veterinary Medicine, Ghent University, Belgium. ³Clinical Science and Services, The Royal Veterinary College, Hatfield, UK

Phenobarbital is the most commonly used first‐line anti‐epileptic drug in dogs. In human medicine, a clinical syndrome called “anticonvulsant hypersensitivity syndrome (AHSS) can occur within 1–8 weeks after initiation of phenobarbital treatment, consisting of a triad of fever, internal organ involvement (lymphadenopathy, hepatomegaly, splenomegaly) and a skin rash. Here we report the clinical and histopathological findings in a dog with suspected AHSS.

A 6‐year‐old, male neutered Beagle was presented with acute onset of lethargy, icterus, fever and coagulopathy 7 weeks after initiation of phenobarbital treatment. The dog developed acute liver failure and despite cessation of phenobarbital and institution of supportive treatment his clinical condition deteriorated quickly and he died 3 days after the onset of clinical signs. A complete necropsy revealed multiple hemorrhagic foci, generalized icterus, splenomegaly, markedly enlarged abdominal lymph nodes, and an enlarged, pale and fragile liver. No skin abnormalities were seen. PCR testing for Leptospira spp returned negative. Histopathology revealed periacinar liver damage, in favor of a toxic event. Based on these findings, the dog was diagnosed with a toxic hepatopathy, most likely caused by phenobarbital, and the combination with the lymphadenopathy raised the suspicion of AHSS.

This is the first case report of suspected AHSS after phenobarbital treatment in a dog and the first description of the pathological findings. Clinicians should be aware of this serious and possibly fatal complication. With aggressive and early treatment, chances of survival are good in human patients.

Post‐operative symptomatic pneumorrhachis in a dog with a thoracolumbar intervertebral disc extrusion

I. Cornelis, P. Monticelli, S. De Decker

Clinical Science and Services, Royal Veterinary College, Hatfield, UK

Although pneumorrhachis, the presence of air in the vertebral canal, is extensively described in human medicine, it has been described only twice in veterinary literature.

A 6‐year‐old crossbreed presented with acute, progressive ambulatory paraparesis localized to the T3‐L3 spinal cord segments. MRI revealed an L1‐L2 intervertebral disc extrusion, which was removed by a right‐sided T13‐L2 hemilaminectomy. Surgery and recovery from anesthesia were uneventful. One day after surgery, the dog demonstrated slight deterioration, being non‐ambulatory paraparetic. The dog however became paraplegic with intact nociception and marked thoracolumbar hyperesthesia 48 hours after surgery. A CT scan of the thoracolumbar vertebral column revealed the presence of a spherical, gas filled structure at the level of T13. The structure had a maximum diameter of 4.8 mm, filling up approximately 50% of the vertebral canal and was associated with marked spinal cord compression. A hyperdense lesion possibly surrounding the gas bubble was concurrently identified, so the dog was presumptively diagnosed with an extradural gas bubble and hematoma, causing marked spinal cord compression. Revision surgery confirmed the presence of a hematoma, which was removed. The dog gradually improved and was neurologically normal 6 weeks after surgery. In agreement with reports in human medicine, pneumorrhachis in this dog was possibly caused by ongoing intervertebral disc disease (vacuum phenomenon) or by entrapment of air in the vertebral canal during surgery.

Although pneumorrhachis is a rare condition, it should be considered a possible cause for early post‐operative neurological deterioration in dogs undergoing decompressive spinal surgery. Surgical revision might result in a good outcome. This is the first case report of post‐operative pneumorrhachis after thoracolumbar hemilaminectomy in a dog.

Endothelin‐1 expression in a canine model of spinal cord injury

D. Mayer^1,2, A. Oevermann^1,3, T. Seuberlich^1,3, M. Vandevelde^1,2, A. Casanova‐Nakayama⁴, S. Selimovic‐Hamza^1,3, D. Henke^1,2

¹Division of Neurological Sciences, Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Switzerland, ²Department of Clinical Veterinary Medicine, Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Switzerland, ³Department of Clinical Research and Veterinary Public Health, Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Switzerland, ⁴Centre for Fish and Wildlife Health, Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, Switzerland

The pathophysiology of ascending/descending myelomalacia (ADMM) following canine intervertebral disc (IVD) extrusion remains poorly understood. Vasoactive molecules may contribute to this lesion.

The aim of the study was to investigate the expression of endothelin‐1 (ET‐1) in the uninjured and injured canine spinal cord and its potential association with intramedullary hemorrhage and extension of myelomalacia.

Spinal cord tissue of 11 normal control dogs and 34 dogs with IVD extrusion was examined histologically at the level of the extrusion (epicenter) and in segments remote from the epicenter. Endothelin‐1 expression was examined immunohistochemically and by in situ hybridization. Using statistical analysis, we searched for associations between the expression of ET‐1 and the severity of intramedullary hemorrhage or the extension of myelomalacia.

Endothelin‐1 was mainly expressed by astrocytes, macrophages and neurons and only rarely by endothelial cells in both control and affected dogs. In astrocytes at the epicenter, ET‐1 expression was significantly higher in affected dogs than in control dogs irrespective of the grade of hemorrhage or myelomalacia (P < 0.001, P = 0.001, respectively). ET‐1 expression in neurons at the epicenter was lower than in control dogs (P = 0.004, P = 0.008, respectively). In both astrocytes and neurons, there was a higher ET‐1 expression in spinal cord regions remote from the epicenter than in the epicenter itself.

Our observation of enhanced ET‐1 expression over multiple spinal cord segments could help to explain the pathogenesis of ADMM. However, more effective quantitative techniques and larger case numbers are required to investigate this further.

Evaluation of cerebrospinal fluid biomarkers in paraplegic dogs with intervertebral disc herniation

S.I. Wicha, R. Carlson, A. Tipold, V.M. Stein

Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany

The definition of a reliable prognosis is challenging in paraplegic dogs with intervertebral disc herniation (IVDH). Tau protein, macrophage inflammatory protein 3 beta (MIP3b) and glial fibrillary acidic protein (GFAP) are potential markers of spinal cord injury. In the current prospective study the value of these substances as biomarkers in cerebrospinal fluid (CSF) for establishing prognosis in paraplegic dogs should be assessed.

Concentrations of tau protein, MIP3b and GFAP were measured in cisternal and lumbar CSF samples using ELISA assays in 42 dogs. The dogs were classified as grade IV or grade V according to the presence (n = 19) or absence (n = 17) of deep pain sensation. Six healthy dogs served as controls. Outcome of dogs was monitored by neurological control exams over at least four weeks after surgery.

Paraplegic dogs had significantly (P < 0.05) higher tau protein and MIP3b levels than the control group of which lumbar concentrations were also significantly higher compared to cisternal CSF samples. GFAP only showed significantly higher values in cisternal CSF in dogs with grade V compared to the control group. CSF concentrations of tau protein, MIP3b and GFAP could not discriminate between grade IV and V. Cisternal tau protein values were significantly lower in dogs showing neurological improvement at least one grade within four weeks.

In conclusion tau protein, MIP3b, and GFAP values were significantly increased in dogs with IVDH and only cisternal tau protein concentrations seem to be correlated with the outcome of paraplegic dogs. The measurement of multiple biomarkers did not enhance outcome prediction.

Bone remodeling after conservative management of hypovitaminosis A in an african lion

J. Siedenburg¹, S. Wicha¹, V. Molnár², P. Dziallas¹, M. Shamir³, V.M. Stein¹, A. Tipold¹

¹Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany, ²Zoo Hannover, Hannover, Germany, ³Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Jerusalem, Israel

A four‐month‐old, intact, captive male African lion (Panthera leo) was presented with a history of mild vestibular signs. Serum Vitamin A levels were decreased.

To confirm the diagnosis of suspected hypovitaminosis A associated occipital bone malformation, computed tomography (CT) and magnetic resonance imaging (MRI) of the skull were performed. To obtain comparable ratios, CT and MRI based measurements were normalized with skull width and diameter of vitreous humor. Tentorium cerebelli and occipital bone were thickened and cerebellar herniation was evident on MRI T2w midsagittal planes. The tentorium cerebelli/skull width ratio (TCR) was 0.0839, basisphenoid/skull width ratio (BBR) 0.067, occipital bone/vitreous humor ratio (OBR) 0.5. A cervical intramedullary T2w hyperintensity extending for at least two cervical vertebrae was visible. Conservative treatment consisted of intramuscular vitamin A supplementation (2000 IU/kg/week for four weeks, 2000 IU/kg/14 days for five months, than 1000 IU/kg/14 days) and feeding of whole carcasses.

After three months the neurological status improved and only a very slight ataxia was visible. In control MRI examinations the TCR declined to 0.0538, the BBR to 0.0462, and the OBR to 0.46. Though the tentorium cerebelli osseum and the occipital bone were still thickened and the cerebellum remained mildly herniated, cervical hyperintensities were no longer visible. Another five months later MRI ratios and pathologies in CT scans changed again (TCR 0.0463, BBR 0.0429, OBR 0.51). A subtle cerebellar herniation was still evident. In conclusion, vitamin A supplementation seems to ameliorate clinical signs and positively influence bone remodeling in young lions with hypovitaminosis A.

Distal polyneuropathy in a birman cat with toxoplasmosis

L. Mari¹, G.D. Shelton², L. De Risio¹

¹Animal Health Trust, Newmarket, UK, ² Department of Pathology, School of Medicine, University of California, San Diego, USA

A 6‐year‐old female spayed Birman cat presented with a history of weight loss and stiff and short‐strided gait in the pelvic limbs progressing to non‐ambulatory tetraparesis over six weeks.

At presentation, poor body condition, dehydration and generalized muscles wastage were evident. Neurological examination revealed mildly depressed metal status, non‐ambulatory flaccid tetraparesis and severely decreased proprioception and spinal reflexes in all four limbs. No hyperalgesia was elicited on spinal or muscles palpation. The neuroanatomic localization was to the peripheral nervous system.

Hematology, FIV/FeLV serology, serum biochemistry including CK and T4, thoracic radiographs and abdominal ultrasound did not reveal significant abnormalities.

Electromyography revealed fibrillation potentials and positive sharp waves in axial and appendicular muscles. Motor nerve conduction velocity was decreased and amplitude was severely reduced in ulnar and sciatic‐tibial nerves. On muscle biopsies, several intramuscular nerve branches were variably depleted of myelinated fibers and contained myelin ovoids. Some of the depleted nerve branches showed an excessive mononuclear cellularity. The biopsy of the common peroneal nerve was normal. IgG and IgM Toxoplasma Gondii serology titers were 1:200 and 1:160 respectively.

Fluid therapy and oral clindamycin 15 mg/kg every 12 hours were initiated. The cat started improving within 24 hours and was ambulatory within 4 days. Serology titers and neurological examination were normal 11 and 16 weeks post initiation of the treatment respectively. Clindamycin was discontinued after 16 weeks. No relapse was reported during the following 6 months.

To our knowledge, this is the first report of distal polyneuropathy associated with toxoplasmosis in a cat.

Diagnostic value of myocytic MHC‐II expression in the diagnosis of canine immune‐mediated myositis (CIMM)

M. Rosati, M. Leipig, K. Matiasek

Section of Clinical and Comparative Neuropathology, Ludwig‐Maximilians University, Munich, Germany

Lymphocytic invasion of predegenerate myofibers resembles the hallmark of CIMM. However, patchy lesion distribution and preceding treatment may preclude detection of specific infiltrates on microscopy. Thus immunohistochemical markers have been used to increase sensitivity and specificity of biopsy studies. Amongst those MHC‐II was evaluated in immune cells. Since myocytes also may act as antigen‐presenting cells, their MHC‐II expression was evaluated with regards to aiding CIMM diagnosis.

34 CIMM dogs, 10 dogs with non‐inflammatory myopathy and 10 dogs with neurogenic muscle atrophy were evaluated immunohistologically for expression of CD3, CD8, CD20, IBA‐1 and MHC‐II in immune cells and myocytes, respectively. The expression was scored (all markers) and sorted for subcellular distribution (MHC‐II) after which group specific data were obtained according to standard algorithms.

Myocytic MHC‐II expression was significantly increased in CIMM if compared to the other diseases (P ≤ 0.02), which only stained weakly positive in 35% of cases. There was a moderate correlation (0.52; P = 0.01) between CD3 and MHC‐II for CIMM cases. With a cut off between scores 1 and 2, MHC‐II reached 100% specificity and 75% sensitivity with 23/34 CIMM (67.6%) staining positive. The overall calculated accuracy was 83%.

MHC‐II expression is a valid diagnostic marker for CIMM that extends beyond inflammatory foci. Sub threshold MHC‐II expression requires further investigation since animals treated with corticosteroids might have not reached cut‐off threshold.

MRI findings in a carbon monoxide intoxication in 2 dogs

M. Kolecka, S. Schulze, D. Farke, Ch. Söffler, M. Kramer, K. von Pückler, M. Schmidt

Small Animal Clinic Department of Small Animal Surgery, JL University, Giessen, Germany

A six years old female intact Jack Russell Terrier was found in a burning house without consciousness. After emergency treatment the dog showed ataxia, circling and vocalization. Magnetic resonance imaging was performed 13 days after admission. T2W, FLAIR and diffusion weighted sequences revealed bilateral symmetrical diffuse and homogeneous hyperintensity of the caudate nuclei. ADC mapping showed a hyperintensity of the caudate nuclei. Four weeks after admission the dog showed no neurological deficits and was discharged.

A second dog (4 years old neutered male crossbreed) was presented 2 weeks after smoke exposure. Initially the dog showed no abnormalities. At the presentation the dog was obtunded and disorientated, showing signs of cerebellar ataxia and proprioceptive deficits. T2W and FLAIR images revealed a heterogeneous hyperintensity of both caudate nuclei. Their signal was hypointense in T1. Generalized hyperintensity of the grey matter surrounding the cerebellar foliae was visible in T2w and FLAIR sequences. Due to progressive deterioration of clinical signs the dog was euthanized 5 months later.

The MRI findings presented in this report are partially compatible with acute and chronic findings reported in human patients after carbon monoxide intoxication. Hyperintense signal changes of the basal nuclei, hippocampus and cerebellum in T2W and FLAIR images with restricted diffusion were major findings in the acute phase. In the chronic phase changes involve predominantly the white matter. Lesions were observed as bilateral diffuse hyperintense signal changes in T2w and FLAIR sequences with a restricted diffusion. Cerebellar involvement was observed in the acute and chronic phase.

Residual disc volumes in chondrodystrophic versus non‐chondrodysrophic dogs with intervertebral disc disease treated by assisted mini‐hemilaminectomy

F. Innerkofler¹, K. Matiasek², S. Medl¹

¹Neurology Referral Service, Tierklinik Babenhausen, Germany, ²Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig‐Maximilians University of Munich, Germany

For years, hemilaminectomy (HL) has been the most advocated decompression technique for surgical therapy of intervertebral disc disease (IVDD) in chondrodystrophic (CDD) and non‐chondrodystrophic dogs (NCDD). However mini‐hemilaminectomy (MH) very early has been shown to preserve better the stability of the vertebral column and to yield considerably more promising results than HL in terms of both postoperative status and recovery time.

This monocenter trial evaluated the efficacy of volume reduction by MH in combination with power‐fenestration or small corpectomy in CDD and NCDD suffering from thoracolumbar IVDD. Medical charts of dogs with thoracolumbar IVDD from 2010–2015 were reviewed. Inclusion criteria were (1) IVDD documented by native‐phase CT images pre and post surgery and (2) treatment via MHL plus small corpectomy or power fenestration. On serial images, the area of the spinal canal occupied by disc material was assessed via image analysis. Thereby, Filling Percentage (FP), Maximum Filling Percentage (MFP) pre surgery, Residual Filling Percentage (RFP) and Maximum Residual Filling Percentage (MRFP) post surgery, as well as Residual Disc Percentage (RDP) were calculated.

A total of 74 patients were included (CDD: 59, NCDD:15). The mean FP was 27.9 ± 13.2%, mean RFP 10.3%±5.1%, mean MFP 48.5%±19.8%, mean MRFP 18.9 ± 9.1% and mean RDP was 31.2 ± 18.5% (CDD: 31.0 ± 17.5%, NCDD: 31.8 ± 22.7%).

Assisted MHL comprises a tissue sparing decompression technique that proved successful in both CCD and NCDD, likewise. Volume reduction as assessed by RDP appears superior to previously published.

Correlation of transcranial magnetic motor evoked potentials and mri morphometry in dogs with functional motor recovery after intervertebral disc herniation: a follow‐up study

J. Siedenburg¹, H.L. Amendt¹, P. Dziallas¹, K. Rohn², A. Tipold¹, V.M. Stein¹

¹Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Hannover, Germany, ²Department of Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Hannover, Germany

The definition of a reliable prognosis in dogs with intervertebral disc herniation (IVDH) has been subject to extensive investigations. Magnetic resonance imaging (MRI) morphometric measurements such as L2 normalized ratios of compression length (CLR) and T2 weighted hyperintensities (T2WLR) correlate with severity of clinical signs but do not provide information about functional integrity of the spinal cord. Transcranial magnetic stimulation (TMS) induces magnetic motor evoked potentials (MMEPs) reflecting spinal cord functional impairment due to spinal cord diseases.

This prospective study aimed to correlate morphometric MRI findings and MMEPs with the course of neurological signs of 20 paraplegic dogs due to thoracolumbar IVDH and neurological improvement within one month after surgical decompression.

MMEPs were assessed in thoracic and pelvic limbs before decompressive surgery, at improvement within one month and 3 months after surgery and MRI was conducted before and 3 months after surgery. Before decompressive surgery no MMEPs could be measured in the plegic limbs. In 9/20 dogs MMEPs could be elicited in the pelvic limbs when motor improvement was noted within one month and in 18/20 dogs 3 months after surgery. Statistical analysis of post‐surgically recorded pelvic limb MMEPs showed a significant increase in peak‐to‐peak amplitudes whereas onset latency significantly decreased. CLR and T2WLR were not significantly correlated with the MMEPs metrics. The comparison of MRI morphometric ratios pre surgery and three months post surgery revealed a significant decrease of CLR (P < 0.004) whereas decrease of T2WLR did not reach the significance level.

In conclusion, MMEPs reflect spinal cord recovery after severe functional impairment. However, correlation of MMEPs with MRI morphometrics could not be confirmed.

Assessment of presence, prevalence and risk factors associated to phantom limb pain in a client‐owned dog population after limb amputation

M. Menchetti^1,2, A. Gallucci², G. della Rocca³, L. Matiasek⁴, K. Matiasek¹, F. Gentilini², G. Gandini², M. Rosati¹

¹Section of Clinical and Comparative Neuropathology, Ludwig‐Maximilians University, Munich, Germany, ²Department of Veterinary Medical Science, University of Bologna, Italy, ³Department of Veterinary Medicine, University of Perugia, Italy, ⁴Neurology Referral Service, Tierklinik Haar, Haar, Germany

Phantom Limb Pain (PLP) refers to pain perceived in the area of an amputated limb. Despite the comparatively high rate of limb amputation in dogs, occurrence of PLP has not been systematically studied. Hence, we screened a client‐owned population of dogs with limb amputation through an online survey aimed to document PLP prevalence, risk factors and owner´s perception of their pets´ quality of life (QoL).

The 75 questions survey evaluated reasons of amputation, pain before and after amputation, pain frequency (expressed as daily, weekly, monthly or yearly episodes) and QoL after amputation. Data were analysed with a Chi‐squared test.

156 dog owners completed the survey. The main reasons for amputation were cancer (59%) and trauma (35%). According to the owners´ perception, pain appeared similar before (81%) and after (86%) amputation (P = 0.44). Over time, 66% of dogs experienced pain between 24 hours to 1 week, 20% between the second and fourth week, 9% between one and three months and 5% between three and six months after amputation. Duration of preamputation pain correlated positively to the frequency of painful episodes after amputation (P = 0.001). Despite 22% of owners were not satisfied with pain control, 86% of them did not regret the decision of amputation.

Post‐amputation pain is a common problem in dogs affecting 86% of patients and requiring appropriate treatment. Besides pain reported within the first week after amputation, 20% of dogs showed pain at a later moment resembling PLP. Duration of preamputation pain is a risk factor associated with occurrence of PLP.

vascular and metabolic compromise of L7 dorsal root ganglia in dogs with painful nerve root compression

M. Menchetti^1,2, U. Foitzik¹, M. Rosati¹, T. Gödde³, A. Blutke¹, F. Steffen⁴, H. Volk⁵, T. Flegel⁶, R. Cappello⁷, M. Lowry⁸, G. Gandini², K. Matiasek²

¹Section of Clinical and Comparative Neuropathology, Ludwig‐Maximilians University, Munich, Germany, ²Department of Veterinary Medical Science, University of Bologna, Italy, ³Neurology Referral Service, Tierarztpraxis Stauffeneck, Piding, Germany, ⁴Neurology Unit, Tierspital, Vetsuisse Faculty, University of Zurich, Switzerland, ⁵Clinical Science and Services, Royal Veterinary College, Hatfield, UK, ⁶Section of Neurology, Department of Small Animal Medicine, University of Leipzig, Leipzig, Germany, ⁷North Downs Specialist Referrals, Bletchingley, UK, ⁸Davies Veterinary Specialists, Higham Gobion, Hitchin, UK

Neuroforaminal Stenosis (NFS) and consequent nerve root compression has been shown to cause morphological changes of entrapped blood vessels and increase neuronal VEGF expression in entrapped dorsal root ganglia (DRG). These findings indicate adaptive changes to hypoxia and circulatory impairment. Reduced oxygen supply could furthermore stimulate a shift in neuronal metabolsim and ultimately influence neuronal function. To challenge this hypothesis we evaluated the expression of neuroglobin (NGB), carbonic anhydrase IX (CA‐IX), monocarboxylate transporter‐1 (MCT‐1) and ‐4 (MCT‐4) in compressed canine DRG via immunohistochemistry.

Altogether, 15 L7‐DRG were evaluated from nine dogs by lumbosacral NFS. Results were compared to age‐/breed‐matched non‐compressed DRG.

All entrapped DRG showed significant neuronal positivity for NGB (P < 0.0001), CA‐IX (P < 0.0001), MCT‐1 (P < 0.0001) and MCT‐4 (P < 0.0001). Substantial increase of endothelial MCT‐1 (P = 0.005) and MCT‐4 (P = 0.02) expression throghout the endoneurium was seen. Furthermore, in all entrapped DRG satellite cells showed significant immunoreactivity for NGB (P = 0.02), CA‐IX (P = 0.001), MCT‐1 (P = 0.02) and MCT‐4 (P = 0.03) expression.

Local increase of neuronal NGB is indicative of adaptative survival mechanism to hypoxic conditions through increased neuronal oxygen binding capacity. A shift towards glycolytic metabolism had been identified through increased expression of CA‐IX and of MCTs meant to prevent intracellular acidosis. The involvement of satellite cells further indicates activation of scavanging mechanisms. These findings highlight significant neuronal distress, that is likely to contribute to aberrant electrical activity, neuronal drop out and persistence of neuropathic pain.

Evaluation of the risk factors and ABCB1 genotype in dogs affected by refractory idiopathic epilepsy

T. Gagliardo¹, F. Gentilini¹, A. Gallucci¹, M. Menchetti¹, M. Turba², E. Bianchi³, A. Cauduro⁴, D. Corlazzoli⁵, S. Gianni⁶, M. Baroni⁷, M. Bernardini⁸, G. Gandini¹

¹Department of Veterinary Medical Sciences, University of Bologna, Italy, ²Genefast, Bologna, Italy, ³Department of Veterinary Medical Sciences, University of Parma, Italy, ⁴Neurovet Professional Association, Milan, Italy, ⁵Roma Sud Veterinary Clinic, Rome, Italy, ⁶Gran Sasso Veterinary Clinic, Milan, Italy, ⁷Valdinievole Veterinary Hospital, Pistoia, Italy, ⁸Portoni Rossi Veterinary Hospital, Bologna, Italy

The aims of this study were to evaluate the risk factors in a population of dogs affected by refractory idiopathic epilepsy (RIE) and assess the frequency of the ABCB1 gene mutation (c.‐6‐ 180T>G), previously associated to phenobarbital‐resistant idiopathic epilepsy in Border Collies (BCs).

The multicentric study had a cross‐sectional design. Among a population of idiopathic epileptic dogs, 52 dogs affected by RIE (defined as a condition in which two anti‐epileptic drugs at adequate serum concentration did not achieve a decrease in seizure frequency ≥50%) were found. Breed, gender, body weight (divided as > or <20 kg), age at the onset of seizures (<12 m; 12–24 m; 25–36 m; >36 m) and seizure type (cluster/single and generalized/focal) were analyzed.

The most represented breeds were mongrel (40%) and BC (7%). The median weight was 19.5 kg. The median age at onset of seizures was 21 months. Cluster seizures were present in 55% of dogs, including 33%, which experienced status epilepticus. The most common seizure type was generalized tonic‐clonic (88%).

BCs were significantly (P < 0.001) at higher risk to develop RIE. Parameters significantly associated to RIE were: weight >20 kg (Relative Risk (RR):1.9), age at onset seizure between 12–24 month (RR: 2.7), and cluster seizure (RR: 4.8).

The ABCB1 mutation was present in the 56% of the dogs, 50% in a homozygous and 50% in a heterozygous state. The ABCB1 mutation was also identified in breeds different from BC.

Besides identifying clinical risk factors, the study demonstrates that other polymorphisms may be responsible for RIE in dogs.

Synringomyelia in the French bulldog

C. Ricco¹, F. Samarani², E. Gomes¹, L. Cauzinille¹

¹Centre Hospitalier Vétérinaire Frégis, Arcueil France, ²Animal Health Trust, Newmarket, UK

Syringomyelia (SM) is a well‐recognized spinal cord malformation that often affects the cervical segment and can manifest clinically by pain, phantom scratching, and proprioceptive deficits. This disease has been well described in the Cavalier King Charles Spaniel (CKCS) and more recently in the Griffon Bruxellois (GB). The aim of this study was to assess the prevalence of SM in the French Bulldog (FB) and to describe the common clinical manifestations, outcome and prognosis. Of the 850 FBs that presented within 3.5 years at our institution, 9.5% (12 cases) of FBs with clinical signs referring to a lesion along the cervical spinal cord tract, presented SM. Unlike the clinical signs in the CKCS and GB, the typical neck pain and scratching behaviour were rare features; proprioceptive deficits were a common finding. It is hypothesized that this prevalence may be higher considering the possible silent SM and the lack of magnetic resonance imaging in all dogs with cervical involvement. We emphasize that SM should be considered a differential diagnosis for FB with a primary complaint referring to the cervical region.

Seizures do not mask the pattern of pervasive changes in cats with hypertensive encephalopathy

S. Bertram^1,2, L. Matiasek³, M. Rosati¹, E. Wagner¹, H.A. Volk⁴, A. Fischer², K. Matiasek¹

¹Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig‐Maximilians University, Munich, Germany, ²Section of Neurology, Centre for Clinical Veterinary Medicine, Ludwig‐Maximilians University, Munich, Germany, ³Neurology Referral Service, Tierklinik Haar, Haar, Germany, ⁴Clinical Science and Services, Royal Veterinary College, Hatfield, UK

Systemic arterial hypertension impacts on the brain by malperfusive and pervasive effects that show a characteristic topography and therefore may allow for an imaging diagnosis of feline hypertensive encephalopathy (FHE). Neurological complications of FHE, on the other hand, include seizures in up to 30% of affected animals.

It was the aim of this study to evaluate the impact of seizures on the spatial pattern of pervasive changes in order to differentiate target areas of hypertensive damage from those prone to seizure‐related blood brain barrier breakdown (B4).

The study enrolled brains of 31 cats, including 9 epileptics, with FHE identified through blood pressure increase, compatible primary lesions and target organ damage of brain vessels. Brain tissue was screened for actual and post‐resorption stages of edema, perivascular microgliosis, parenchymal and vascular lesions.

Apart from a subsignificantly increased involvement of hippocampus, caudate nucleus and marginal gyrus by actual edema and aquaporin‐4 expression, there were no differences in between lesion maps or damage scores of epileptic and non‐epileptic FHE cases (P ≥ 0.05).

Brain edema and perivascular gliosis in FHE resemble blood pressure‐induced vascular dysfunction rather than consequences of local excitotoxicity. The lesion pattern persists throughout epileptic and non‐epileptic FHE courses and therefore allows for an accurate imaging diagnosis of systemic hypertension.

Altered expression of an excitatory tachykinin neuropeptide in seizure‐associated feline hippocampal sclerosis

M. Rosati¹¹, E. Wagner¹¹, A. Fischer²², L. Matiasek³, T. Flegel⁴, K. Matiasek¹¹

¹Section of Clinical and Comparative Neuropathology, Ludwig‐Maximilians University, Munich, Germany, ²Section of Clinical and Comparative Neurology, Ludwig Maximilians University, Munich, Germany, ³Neurology Referral Service, Tierklinik Haar, Haar, Germany, ⁴Section of Neurology, Department of Small Animal Medicine, University of Leipzig, Leipzig, Germany

Substance P (SP) has pro‐epileptic effects due to its neurokinin‐1 receptor activation evoking neuronal depolarization and enhancing excitation. During status epilepticus hippocampal expression of SP increases the electrical activity of the region, which becomes more prone to seize. Considering SP a candidate for neuromodulation we investigated its expression in feline hippocampi with (HS) and without (NHS) seizure‐associated hippocampal sclerosis.

Immunohistochemical distribution of SP at the temporo‐ventral body of the hippocampus was assessed in 26 epileptic cats and compared to non‐neurologic controls. Algorithms for analysis comprised semiquantitative scoring of SP expression throughout hippocampal subregions and its subcellular distribution.

All hippocampi showed SP synaptic immunoreactivity in the external and internal stratum moleculare of dentate gyrus, pyramidal layer, stratum radiatum, stratum oriens and more diffusely within parahippocampal gyrus (PHG). SP expression was reduced in epileptic cats reaching statistical significance (P < 0.02) in all segments but dentate gyrus. SP was significantly decreased in HS compared to controls in CA3, CA2, CA1 and PHG. NHS differed from controls only in CA1. A significant reduction of SP expression was seen after SE in CA3 (P = 0.052) and PHG (P = 0.004).

Decrease of SP expression in the hippocampus of epileptic cats in course of HS could be attributed to loss of synapses in course of HS. SE and prolonged excitatory electrical activity might as well decrease SP expression through its synaptic depletion. Assessment of candidate neuropeptides for neuromodulation is a preliminary step towards development of adjuvant therapies to assist conventional antiepileptic treatments.

Association between MRI assessed disc degeneration and recurrence of clinical signs following surgical treatment of thoracolumbar intervertebral disc disease in dogs

S. Longo, D. Burnand, S.A. Gomes, P. Freeman

The Queen's Veterinary School Hospital, Department of Clinical Veterinary Medicine, University of Cambridge, UK

An association between the number of calcified intervertebral discs (IVDs) on survey radiographs and recurrence of clinical signs following surgery for thoracolumbar intervertebral disc extrusion (IVDE) in dogs has been previously described. MRI is now the imaging modality of choice in canine IVDE. The aim of this study is to examine the relationship between MRI‐assessed IVD degeneration and recurrence of clinical signs in surgically treated dogs.

Medical records and MRI‐studies of dogs undergoing hemilaminectomy without fenestration for thoracolumbar IVDE at two centers (2010–2014) were reviewed. Recurrence was assessed by telephone follow‐up to either referring vets or owners. Recurrence was recorded if thoracolumbar pain or neurological deficits occurred after a period of at least 6 months during which recovery was seen. Fifty‐four dogs were included and MRI studies from T11 to L3 were assessed for number of degenerated discs in addition to the affected one in mid‐sagittal T2W‐images.

In common with previous studies, most animals were Dachshunds (43%) and mean age was 5.75 yrs (2.6–11). 96% of extruded discs were between T11 and L2. Recurrence of clinical signs was seen in 13/54 (24%) of cases, and 100% of these cases had at least one other degenerate IVD seen on initial MRI. In the non recurrence group 23/41 (56%) showed no other degenerate discs. There was a significant correlation between number (P = 0.022) of degenerate discs and recurrence.

These results might be of value in predicting recurrence in dogs, assisting surgical decision making with regard to prophylactic fenestration.

Outcome and complication rate in canine cervical disk extrusions treated either with a ventral slot or a cervical hemilaminectomy procedure

D. Faissler, S. Samuels

Cummings School of Veterinary Medicine at Tufts University, Grafton, USA

Cervical disk extrusions accounts for 15–25% of canine IVDD. The purpose of this study was to assess post‐surgical complications, short and long‐term outcome canine cervical IVDD treated with either a ventral slot (VSL) or cervical hemilaminectomy (CHL) procedure.

Our hypothesis is that dogs undergoing VSL or CHL have a similar incidence of post‐surgical complications and outcome, but a significantly higher incidence of recurrence at an adjacent disk space after a VLS procedure. Inclusion criteria were complete medical history, advanced diagnostic imaging and postsurgical follow‐up of >2 years.

Eighty‐seven dogs were included; 61 dogs underwent a VSL surgery and 26 dogs had a CHL procedure. There was no difference in breed, weight, age, sex, onset, and clinical presentation, affected disk space and degree of spinal cord compression between the two groups. Dogs undergoing CHL had a lateral or foraminal extrusion more frequently. Surgery time, days on a fentanyl CRI and hospitalization time were significantly shorter in the VSL group. The rate of adverse events assessed with SAVES grades was similar in both groups (8.4% vs. 7.7%). Both procedures had good return to normal function (80% vs. 88%). Dogs in the VSL group had a higher recurrence rate than in the CHL group (21.7% vs. 7.7%) with the adjacent disk space affected frequently (13.3% vs. 3.8%).

The VSL procedure is faster, requires less post‐operative pain medication, and has a shorter hospitalization time. However, with the VSL procedure patients are at a higher risk of recurrence, especially at the adjacent disk.

Inheritance of Chiari‐like malformation: can a mixed breed reduce the risk of syringomyelia?

S Knowler¹, H v/d Berg², A McFadyen³, E Noorman⁴, R La Ragione¹, C Rusbridge^1,2

¹School of Veterinary Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK, ²Fitzpatrick Referrals, Godalming, UK, ³AKM‐STATS, Glasgow, Scotland, UK, ⁴Dierenkliniek den Heuvel, Oirschotesweg NL

Chiari‐like malformation (CM) and syringomyelia (SM) are complex multifactorial disorders. Quantitative analysis in a family group was used to investigate the inheritance and feasibility of crossbreeding a mesaticephalic normal Australian terrier and brachycephalic CM affected Griffon Bruxellois (GB) and then backcrossing to produce individuals free of CMSM and regain breed type.

The 27 dog family had 5 foundation dogs which had been members of a 155 GB dog cohort investigated in a previous study and which were identified for eight traits significant for CM and SM affectedness. Moreover, a Quantitative Trait Locus analysis had shown six of these to be associated with 5 Canis Familiaris Autosomes. T1‐weighted sagittal DICOM images of the brain and cervico‐cervical junction were analyzed for five significant traits (2 angles, 2 lines and a “best fit” occipital lobe circle diameter), which were useful to distinguish the phenotype.

The mean measurements for mixed and pure‐breed groups were compared. The traits exhibited segregation that may be additive towards the severity of CM. Furthermore, the external phenotypes showed that by outcrossing breed types and careful selection of appropriate conformation characteristics in the first generation, it is possible to regain the GB breed standard and reduce the degree of CM. The four dogs affected with SM in the study all exhibited reduced caudal skull development compared to their relatives.

These traits may be useful to quantify CM and risk of SM to assist breeders with mate selection. Such a system requires validation to ensure appropriateness for all breeds at risk.

A retrospective review of 135 cases of meningioencephalomyelitis of unknown aetiology treated with cytosine arabinoside and glucocorticoids

M.F.E. Hill¹, R.M.A. Packer², P.J. Kenny², S. De Decker², H.A. Volk²

¹Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK, ²Department of Clinical Science and Services, Royal Veterinary College, University of London, Hatfield, UK

Meningoencephalomyelitis of unknown etiology (MUA) is a commonly diagnosed neurological condition in dogs that can be treated by a variety of immunomodulating drugs including cytosine arabinoside. The aims of this study were to review the outcomes (including death and response to treatment) and adverse effects associated with treatment with cytosine arabinoside and glucocorticoids in patients diagnosed with MUA.

Patients were enrolled from the population referred to the Neurology and Neurosurgery service at the Queen Mother Hospital for Animals, Royal Veterinary College, between 2005 and 2014. Inclusion was based upon previously published criteria. Cytosine arabinoside administration was typically by subcutaneous injection at 50 mg/m² every 12 hours over a 48‐hour period, initially, at three weekly intervals. Prednisolone was started at 1 mg/kg every 12 hours and tapered based on clinical response. Outcome data were collected by regular re‐examination visits at our dedicated cytosine arabinoside clinic and a standardised telephone questionnaire.

135 dogs were included in this study. Survival times ranged from 0 to 3030 days (mean 710 days, median 377.5 days, lower quartile 85 days, upper quartile, 1104 days). None of the evaluated variables were significantly associated with prognosis. 9% of dogs demonstrated side effects associated with cytosine arabinoside, which included vomiting or diarrhea (5.2%), calcinosis cutis (1.5%), myelosupression (2.2%), and injection site infection (0.7%). Clients reported 78% of dogs showed one or more side effects associated with glucocorticoid use, these were reduced or alleviated through dose reduction in 98% of cases.

Cytosine arabinoside can be safely used for the long‐term management of MUA, and it has the potential to significantly reduce the side effects associated with concomitant glucocorticoid use through dose reduction.

Imepitoin is well tolerated by healthy cats

O. Engel¹, J. Mueller¹, F. de Vries¹

¹Boehringer Ingelheim Vetmedica GmbH, Ingelheim am Rhein, Germany

Epilepsy in the cat is a serious medical condition as in all species. To date there are no licensed treatments for feline epilepsy and no well‐controlled clinical studies on the efficacy or safety of antiepileptic drugs in cats.

The new antiepileptic drug imepitoin has demonstrated clinical efficacy and safety in dogs to reduce the frequency of generalized seizures due to idiopathic epilepsy.

The aim of this randomized, controlled, blinded GLP study was to investigate the tolerance of imepitoin in clinically healthy male and female cats after repeated oral administration in a laboratory setting. In two studies, 30 cats received twice daily doses of 0, 30, 40 or 80 mg/kg bodyweight for 30 days.

No serious adverse events were observed in any of the dose groups. In the imepitoin treated groups, emesis was observed in some animals temporarily and intermittently mainly in the second and third weeks of treatment. At the highest doses (40 and 80 mg/kg), a slight reduction in food consumption was observed especially at the beginning of the study, with subsequently slightly lower body weights compared to controls. Hematology and clinical chemistry results revealed no relevant changes. The pharmacokinetic profile appeared to be similar to dogs with a Tmax of 1.5 hours.

In summary, in this laboratory study imepitoin was well tolerated in cats, even at very high doses. For definitive evidence on safety and efficacy, clinical trials in feline epilepsy patients are warranted. The studies described here were approved by the relevant authorities for protection of animals.

Use of gabapentin for neuropathic pain treatment in dogs: a prospective clinical trial

A. Seisdedos¹, A. Galán Rodríguez¹, J. Morgaz Rodríguez¹, B. Blanco Navas¹, E. Martín‐Suárez¹

¹Department of Internal Medicine, University of Córdoba, Spain

Neuropathic Pain (NP) is a chronic pain with many forms of presentation and multiple etiologies. Most clinical signs related to NP are difficult to recognize in dogs. Up to the date, there are few studies about the most effective treatment (Grubb 2010, Wolfe and Poma 2010, Maden et al. 2014, Plessas et al. 2015). The objective of this prospective clinical trial was to assess the effectiveness of gabapentin in the treatment of NP in dogs.

Eleven patients followed a 6‐week period treatment with gabapentin at dosage of 15 mg/kg/12 h during the 1st and 6th weeks and 15 mg/kg/8 h from the 2nd to the 5th weeks. They were examined at the first visit (T0) and 3th (T1) and 6th (T2) weeks, obtaining heart rate, respiratory rate, arterial pressure, blood count, blood levels of cortisol and fructosamine. Two questionnaires (Q1 and Q2) for the assessment of pain were performed. Q1 assessed dog's behavior at home and Q2 assessed the patient's pain at the visit.

At the end of the treatment, although without significant differences, all dogs showed a notable decrease in the punctuation in Q2. Cortisol levels decreased progressively during the treatment and significant differences were observed between the T0 and T2.

In conclusion, reductions in cortisol levels and decrease of clinical signs related to NP at consultation make us consider gabapentin 15 mg/kg/8 h as useful for the NP treatment in dogs.

Diagnostic yield and diagnostic accuracy of magnetic resonance imaging‐guided frameless stereotactic brain biopsy in dogs and cats with intracranial disease

A. Staudacher¹, A. Oevermann², F. Forterre³, D. Henke⁴, D. Gorgas¹

¹Division of Clinical Radiology, Department of Clinical Research and Veterinary Public Health, Vetsuisse‐Faculty Bern, Switzerland, ²Division of Neurological Sciences, Vetsuisse‐Faculty Bern, Switzerland, ³Division of Small Animal Surgery, Department of Clinical Research and Veterinary Public Health, Vetsuisse‐Faculty Bern, Switzerland, ⁴Division of Clinical Neurology, Department of Clinical Research and Veterinary Public Health Vetsuisse‐Faculty Bern, Switzerland

Stereotactic brain biopsy (SBB) is currently the least invasive method to obtain a specific histopathological diagnosis of intracranial disease, which is essential to establish a well‐founded prognosis and a rational therapy plan. Frameless magnetic resonance imaging (MRI)‐guided SBB is becoming the standard of care for image‐guided brain biopsy in human medicine, but its diagnostic success has never been investigated in veterinary patients. Therefore, the aim of this prospective study was to evaluate the diagnostic yield and diagnostic accuracy of the MRI‐guided BrainsightTM frameless stereotactic system in a series of dogs and cats with intracranial lesions.

Forty‐five dogs and six cats with intracranial disease, which was confirmed on MRI, underwent MRI‐guided SBB. Routine histopathological examination was performed on the obtained brain biopsy specimen. Brain necropsy was available for comparison of histopathological diagnoses in thirty‐eight animals.

Brain tissue was obtained in all biopsy procedures. The overall diagnostic yield was 80.4% (41/51). The histological diagnosis of SBB was confirmed (complete agreement) in twenty‐six (86.7%) and slightly differed (minor disagreement) in four (13.3%) of the thirty diagnostic cases, which were also available for necropsy. For the thirty‐one patients in the complete and major agreement groups of this study, the accuracy of the histological diagnosis was 100% (31/31).

In conclusion, MRI‐guided SBB using the BrainsightTM frameless stereotactic system is an effective method to collect brain tissue samples resulting in a correct histopathological diagnosis in the majority of patients.

Morphology of the caudal fossa in mesaticephalic and brachycephalic cats

K. Marioni‐Henry¹, T. Schwarz¹, D. Gunn‐Moore¹

¹Hospital for Small Animals, Royal ^Dick School of Veterinary Studies, Roslin, UK

Morphological abnormalities of the caudal fossa are increasingly recognized as a cause of morbidity in many brachycephalic dogs with round broad heads and shortened facial bones such as Cavalier King Charles Spaniels. The study objective was to investigate presence of similar morphological abnormalities of the caudal fossa of mesaticephalic and brachycephalic cats.

The records of the Diagnostic Imaging Service at the R(D)SVS were searched for MRI studies of brain of cats from January 2014 to June 2015. Twenty‐six cases were identified, four MRI were eliminated due to structural intracranial abnormalities. T2W sagittal images of the remaining 22 MRI studies were blindly analyzed by KMH. Subjective assessments included coning of the cerebellar vermis, indentation of the cerebellum by the supraoccipital bone, iso‐ to hyper‐intense material in the middle ear and, when concurrent MRI studies of the spine were available, presence of syringohydromyelia. Measurements of foramen magnum and cerebellar herniation, area of the cerebellum, length of the forebrain and cerebellum were also acquired.

After the MRI studies were reviewed they were unblinded and the data were divided in 2 groups based on the classification of the cat breeds among mesaticephalic (16 cats: 14 Domestic Shorthaired cats, 1 Ragdoll and 1 Maine Coon) or brachycephalic (6 cats: 2 Burmese cats, 1 British Shorthaired, 1 Burmilla, 1 Chinchilla, 1 Tiffany). Cerebellar coning and cerebellar indentation by the foramen magnum was reported in 5/6 cats (83%) of the brachycephalic group versus 8/16 cats (50% for cerebellar coning) and 3/16 (19% indentation) of the mesaticephalic group.

Genetic epilepsy in CANE CORSO and Dogue de Bordeaux

C. Escriou¹, P. Quignon², E. Menzer¹, S. Correard², C. André²

¹Neurology, VetAgro Sup, Lyon Veterinary Campus, France, ²CNRS, UMR 6290, Genetic and Development Institute, Rennes, France

Genetic factors are increasingly being identified as the underlying mechanism of breed specific type of epilepsy in dogs. Prevalence and phenotypic characteristics of epilepsy are well described in popular breeds like Belgian Shepherd, Australian Shepherd, Border Collie or Labrador. To date, no descriptions have been reported in molossoid breeds like Cane Corso and Dogue de Bordeaux.

In order to determine breed specific epilepsy presentation we asked breeders or owners to complete a questionnaire about epilepsy.

We collected 25 epileptic Cane Corso and 5 epileptic Dogue de Bordeaux.

Cane Corso displayed severe epilepsy with very homogenous presentation appearing during teenage (median 17.5 months) with no sex predisposition. All dogs presented generalized seizures and 91% have systematic clusters. 30% of dogs are euthanized or deceased from status epilepticus before 3 years. In 54% of dogs, seizure frequency didn't decreased with anticonvulsants. Epilepsy in Dogue de Bordeaux was similar (generalized seizures and clusters for all dogs) but a juvenile form is observed in 4 dogs (first seizure before 4 months).

In Cane Corso, 17 dogs were related and pedigree analysis is in favor of recessive autosomal transmission.

Whether this severe epilepsy is linked to the size of the dogs as previously described or to the specific underlying genetic factors remains questionable.

Seizures in a coati (nasua nasua) with craniopharyngioma – a case report

D. Farke¹, M. Kolecka¹, S. Kirsten², L. Rydewski², A. Schänzer³, H. Dohmen‐Scheuffler³, C. Herden², M.J. Schmidt¹

¹Clinic for Small Animals‐Surgery, Justus Liebig University, Giessen Germany, ²Institute of Veterinary Pathology, Justus Liebig University, Giessen, Germany, ³Institute of Neuropathology, Justus Liebig University, Giessen, Germany

A ten years old coati was presented with a 3‐week history of generalized seizures, altered consciousness, circling and blindness. Abdominal and chest radiographs, complete blood cell count and biochemistry panel from the referring veterinarian revealed no abnormalities. Neurological examination showed a reduced menace response on both eyes. Magnetic resonance imaging showed an extra‐axial, well demarcated mass lying in the middle cranial fossa, which had a mass effect on the brainstem, cerebellum, thalamus and corpus callosum. The mass was heterogeneous with a central hyperintensity in T2, T2FFE and FLAIR. In T1‐ weighted images a central hypointensity and a moderate contrast enhancement was visible. Differential diagnosis included macroadenoma/ carcinoma of the pituitary gland, germinoma meningioma, lymphoma and craniopharyngioma. The animal was euthanized and a pathological examination was performed. Macroscopic examination revealed a pressure‐induced atrophy of the brainstem. Histological findings included satelitiosis, mild mononuclear cell infiltration within the meninges and a mild vacuolization of the white matter adjacent to the mass. The mass itself was organized in nests of round to polygonal cells with eosinophilic cytoplasm. Few mitoses were visible and within the stroma areas of necrosis and calcification were visible around one big central necrosis. Imunohistochemistry showed that tumour cells strongly expressed epithelial marker, and ß‐catenin (NSE) and showed a low mitotic activity (MIB‐1) <5%. The histology is consistent with a low grade tumor of epithelial differentiation and in combination with the radiological findings a craniopharyngioma of papillary type was diagnosed.

Immunohistological stains were positive for vimentin, cytoceratine, NSE within the stroma and the mass and synaptophysine. They were negative for GFAP, S100 and NF. So the histopathological examination considered a pituitary gland neoplasia most likely.

Acetazolamide‐responsive paroxysmal dyskinesia in a golden retriever puppy

E. Royaux¹, S. Bhatti¹, R. Harvey², L. Garosi³, G.D. Shelton⁴, L. Van Ham¹

¹Department of Small Animal Medicine and Clinical Biology, Ghent University, Belgium, ²Department of Pharmacology, UCL School of Pharmacy, London, UK, ³Davies Veterinary Specialists, Higham Gobion, Hertfordshire, UK, ⁴Department of Pathology, School of Medicine, University of California San Diego, La Jolla, CA USA

Paroxysmal dyskinesias are episodes of abnormal, sudden, involuntary contractions of a group of skeletal muscles that recur episodically. This is the first report of a paroxysmal dyskinesia in a young Golden Retriever.

A twelve‐week‐old female intact Golden Retriever was referred with an 8‐week history of recurring episodes of muscle stiffness and collapse. Episodes were most often triggered by excitement and exercise. Mentation was normal and abnormal autonomous activity was not present during the entire episode. On clinical examination a poor body condition score was noted. Neurological examination revealed generalized muscle atrophy. Complete blood examination did not reveal any abnormalities. Electromyography was performed during an episode of hypertonicity on the awake dog and complete electrodiagnostic testing was performed under general anesthesia. No abnormalities were found. Muscle biopsies were collected and a type 2 fiber atrophy or hypotrophy was recognized. This may be the result of disuse or altered patterns of neural excitability to the muscle fibers. The affected puppy, unaffected littermates, the dam and the sire all tested negative for episodic falling syndrome in CKCS (negative for the BCAN microdeletion). The puppy was not responsive to clonazepam but complete remission was seen with acetazolamide. Now, 1 year later, the dog still receives acetazolamide and is neurologically normal. The owner did not report any side effects of long‐term acetazolamide treatment.

Phenotypically the episodes of the puppy were similar to those of Cavalier King Charles Spaniels with episodic falling syndrome. Further genetic testing including sequencing of the BCAN gene would be necessary to identify an underlying mutation.

Peripheral glycaemia in dogs with limb thrombosis: a prospective study

M. Dolera, L. Malfassi, R. Vailati Facchini, S. Finesso, G. Mazza, S. Pavesi, N. Carrara, S. Marcarini, M. Sala

La Cittadina Fondazione Studi e Ricerche Veterinarie, Romanengo, Italy

The aim of this study was to document the peripheral glycaemia variations in hypoperfused limbs of patients affected by Magnetic Resonance Imaging (MRI)‐confirmed arterial thrombosis.

Eleven dogs were recruited. Inclusion criteria were a clinical examination supportive of limb hypoperfusion and availability of blood cell count, biochemical profile and urine analyses. Two blood samples were sampled, one from the affected limb and one from a healthy limb. Plasmatic glycaemia was measured using an automated glucose analyzer. All the patients underwent a total body MRI that provided the final diagnosis.

The thrombus was located: in the abdominal aorta (7/11), in the subclavian artery (1/11), in the axillary artery (1/11), in the iliac arteries (2/11). Of the total abdominal aortic thrombosis, 3/7 involved also the internal iliac arteries, 2/7 the external ones and 2/7 both. The extent of the thrombosis was classified as grade 1 when the greatest portion of the thrombus did not reach half of the vessel lumen (1/11); grade 2 when the greatest portion of the thrombus was between 1/2 and 2/3 of the vessel lumen (7/11); grade 3 when the thrombus exceeded 2/3 of the lumen (3/11).

A substantial decrease in peripheral glycaemia values was found in sampling arising from the affected limbs. Comparing affected limbs values with healthy limbs measurements from the same patient, the reduction was found from 17.65% to 34.41%. Accounting only the grade 3 scored patients, the percentage of reduction was found up to the 28.34%.

Cortical dysplasia as a cause of drug resistant epilepsy in two juvenile dogs

G.J. Nye¹, H.A. Volk¹, S.L. Priestnall², R. Drees¹

¹Department of Veterinary Clinical Sciences, Royal Veterinary College, Hatfield, Hertfordshire, UK, ²Pathology and Pathogen Biology, Royal Veterinary College, Hatfield, Hertfordshire, UK

Cortical Dysplasia (CD) is a rare condition causing seizures. The condition is only sparsely reported in the veterinary literature. Focal CD is seen in human, especially juvenile, patients as a cause for drug‐resistant epilepsy. A retrospective case study was performed to identify dogs with CD lesions, identifiable on Magnetic Resonance Imaging (MRI) and post‐mortem histopathology.

Two dogs were identified, one with focal polymicrogyria (PMG) and the other with widespread CD and hydrocephalus ex vacuo. Both cases presented with acute‐onset cluster seizure episodes unresponsive to phenobarbital treatment. Both dogs had generalized tonic‐clonic seizures. The dog with PMG additionally had history of behavioural change, focal complex motor seizures and bilateral menace response deficits. On MRI the temporal lobe is affected in both dogs, and the frontal lobes in one of the dogs with regions of poor definition of cortex and white matter. Post‐mortem examination found that both dogs were consistent with a type Ic focal CD (International League Against Epilepsy (ILAE)). Both patients were euthanized for poor seizure control unresponsive to antiepileptic drug treatment.

These case reports highlight that CDs can be a cause for drug resistant epilepsy not only in people but also in dogs. CD should be considered as a differential in young dogs presenting with seizures.

Clinical experience in the use of magnesium and magnesium sulfate as an adjunct therapy in five dogs with generalized tetanus

C. Loeffler, T. Flegel, G. Oechtering, S. Hanemann

Department of Small Animal Medicine, University of Leipzig, Germany

Magnesium sulfate (MgSO4) has been used in humans with tetanus to control muscle spasms and therefore to reduce sedation requirements. The aim of this study was to investigate the effect of supraphysiologic serum magnesium in tetanic dogs and to establish a dosing protocol for the use of magnesium and magnesium sulfate.

Five dogs were presented due to generalized tetanus between January 2014 and May 2015. All dogs received open wound management, equine tetanus antitoxin, metronidazol and sedatives. Magnesium therapy was initiated within 24 to 48 hours after the initial presentation with the goal of increasing total serum magnesium to 2–4 mmol/l (reference range:0.6–1 mmol/l ) based on a therapeutic range from human literature. Serum magnesium concentrations were monitored every 12–24 hours. The MgSO4 infusion was initiated with 10 mg/kg/d and was gradually increased over the following three days to 30 mg/kg/d. Medication was switched from injectable MgSO4 to oral magnesium once normal food intake was assured. Oral magnesium was given with an initial dosage of 20 mg/kg/d divided in three doses and was gradually increased over the following 3–5 days to a maximum of 400 mg/kg/d.

No clinical signs associated with magnesium toxicity like nausea, lethargy, bradycardia or respiratory depression were evident during the therapy. After initiation of magnesium the dogs tolerated the reduction of sedatives. The targeted serum magnesium concentration could not be achieved in any patient. Further studies with markedly higher dosing protocols will be necessary to find out the required dosage and dosing interval for tetanic dogs.

Pancreatitis in dogs with intervertebral disc disease

M‐K. Müller¹, K. Winter², T. Flegel¹

¹Department of Small Animal Medicine, University of Leipzig, Leipzig, Germany, ²Translational Centre for Regenerative Medicine, Leipzig, Germany

Since the early 1980's it was presumed that intervertebral disc disease (IVDD) may lead to pancreatitis particularly if linked to corticosteroid administration and surgery. The purpose of this study therefore was to determine if IVDD is a predisposing factor for pancreatitis in dogs and to evaluate possible influencing factors such as general anaesthesia, surgery and corticosteroid administration.

Three groups of dogs were tested: 1. confirmed IVDD with surgical treatment (n = 71) 2. presumed IVDD without general anesthesia (n = 20) 3. confirmed acute intramedullary lesion without surgical treatment (n = 15). Canine pancreatic lipase was measured (Spec cPL and Snap cPL) at day of presentation and 4 days later. An abdominal ultrasound was performed at day 4. Furthermore the dogs were daily examined for clinical signs of pancreatitis such as anorexia, abdominal pain or vomitus. The diagnosis of pancreatitis was based on two of the following findings: clinical signs, abnormal spec cPL, suggesting abdominal ultrasound results.

A total of 6(5.6%) and 15(4.1%) pancreatitis cases were confirmed on day 0 and 4, respectively. At day 0 a higher percentage of dogs was diagnosed with pancreatitis compared to the other groups. At day 4 the surgically treated dogs showed more pancreatitis cases on percentage basis. However, there was no statistical significance (P = 0.604 and P = 0.214). Additionally, neither of the following factors had a statistically significant influence on the frequency of pancreatitis at day 4: ambulation, administration of NSAID and/or corticosteroids, anesthesia and surgery.

Conclusively, it was not confirmed that IVDD is a predisposing factor for pancreatitis in dogs.

Cervical spinal cord granulomatous meningoencephalomyelitis mimicking neoplasia in three dogs

F. de Strobel, V. Palus, A. Caine, A. De Stefani, G.B. Cherubini

Dick Whire Referrals, Six Mile Bottom, Cambridgeshire, UK

Three cases of focal cervical spinal cord GME (granulomatous meningoencephalomyelitis) with MR (magnetic resonance) features that overlap with those of neoplastic lesions are described.

The three dogs all presented with cervical hyperesthesia and different grades of tetraparesis and ataxia; episodes of fly catching and generalized seizure activity occurred in two cases. A well‐defined intradural‐extramedullary mass, arising from the dorsal margin and invading the dorsal midline of the cervical spinal cord was the common MR feature. The lesions were isointense to the cord in T1w, slightly hypointense in T2w and STIR images and displayed a strong uniform contrast enhancement. Meningeal enhancement or dural tail signs were present in all cases. Mild intraparenchymal contrast uptake was additionally seen in two cases. All lesions were surrounded by intramedullary edema. Cerebrospinal fluid (CSF) analysis showed increased protein concentration and marked pleocytosis in two dogs; in one case the diagnosis of GME was confirmed by biopsy. This dog was euthanized after surgical debulking of the lesion; the other two initially responded to immunomodulatory treatment however one was euthanized after seven months of treatment for relapsing of clinical signs.

GME must be considered in presence of a well‐defined contrast enhancing extramedullary mass, with MR features overlapping spinal cord neoplasms. The careful analysis of MR images to look for additional features including diffuse meningeal enhancement or other areas of parenchymal enhancement, in combination with clinical signs and CSF results, can be helpful in the differentiation between neoplastic and inflammatory spinal cord diseases and in the consequent choice of treatment.

Cervical dysplasia in a 7 months old alpaca mare

J. Nessler¹, R. Eibach², C. Helmer², Ann‐Kathrin Uhde³, M. Hewicker‐Trautwein³, M. Fehr¹, A. Tipold¹

¹Small Animal Clinic, University of Veterinary Medicine, Hannover, Germany, ²Clinic for Swine, Small Ruminants and Forensic Medicine, University of Veterinary Medicine, Hannover, Germany, ³Institute for Pathology, University of Veterinary Medicine, Hannover, Germany

A 7 months old alpaca mare was presented with a 3 months history of waxing and waning ataxia. When the first gait abnormalities were observed vitamin D/phosphate deficiency was diagnosed: serum levels of vitamin D 5.36 µg/l (reference >25 µg/l) and phosphor 0.46 mmol/l (reference 1.45–2.6 mmol/l). Substitution led to marked improvement of the ataxia. Two months later the alpaca developed generalized ataxia and tetraparesis with short steps in the thoracic limbs and hypermetric steps in the pelvic limbs and marked proprioceptive deficits. Muscle tone and spinal reflexes were normal or increased in all limbs. Consciousness and cranial nerves were unremarkable. A cervical lesion was suspected. Computed tomography and magnetic resonance imaging (MRI) in general anesthesia revealed a dramatic compressive myelopathy due to dysplasia of several cervical vertebrae. Dorsal laminectomy at C2‐C3 revealed intramedullary bleeding. Post surgery neurological signs worsened and the alpaca developed apnea. After 5 hours of mechanical ventilation without improvement the alpaca was euthanized. Necropsy confirmed MRI findings: C2‐3 spinal cord segments showed an hourglass like compression and marked intramedullary bleeding; cervical vertebrae were dysplastic. Histopathology revealed bleeding in white and grey matter, moderate gliosis with spheroids, myelinophagia and axonal drop out. These findings were pronounced in C2‐C3 spinal cord segments but visible up to the lumbar spinal cord.

Rickets due to hypovitaminosis D is a well‐known disease in alpacas and may cause scoliosis in humans. Vitamin D and phosphor deficiency might have caused the described cervical deformation in the alpaca, although to the author's knowledge a similar case has not been described yet.

The effects of allogenic mesenchymal stem cell transplantation in experimentally induced spinal cord injury in rats

P. Can¹, F. Pinarlı², S. A. Vural³, T. Delibasi², O. Besalti¹

¹Department of Surgery, Faculty of Veterinary Medicine, Ankara University, Turkey, ²Dışkapı Yıldırım Beyazıt Training and Research Hospital, Ankara Turkey, ³Department of Pathology, Faculty of Veterinary Medicine, Ankara University, Turkey

Spinal Cord Injury (SCI) is a debilitating and devastating condition for humans and also for companion animals. Although substantial level of progress has been reported for medical and surgical treatment of spinal trauma, it is not yet possible to completely retain neuronal function after SCI.

The aim of this study was to investigate the effects of bone marrow‐derived allogenic mesenchymal stem cells (BM‐AMSCs) transplantation in acute stage of the experimentally induced SCI. The study protocol was approved by the Animal Experimentations Local Ethic Committee. One‐day‐old rats were used for stem cell collection. Sixty five rats were grouped as sham control, control and experiment. The effects of BrDU labeled stem cells which were transplanted intraparanchymally 6 hours after the trauma were evaluated at 1st, 3rd, 7th and 21sth days by clinically, histologically, electrophysiologically and immunohistochemically.

There was no difference between the control and experiment group with regard to clinical score, caspase 3, caspase 8, caspase 9 and apoptosis rates. There was a statistically significant improvement in SEP score of the experiment group compared to control group, which were euthanized at 3rd day. Histologic findings were similar in all groups. BrDU labeled stem cells were seen at the injured site of spinal cord with a decreasing rate by the time in the experiment groups.

In conclusion, the transplantation of BM‐AMSCs in the acute stage of the SCI might not provide a dramatical change, but the presence of the BrDU labeled stem cells until 21sth day encourage us for future studies.

Extradural meningeal cystic lesion corresponding to type I meningeal cyst in a dog

F. Tirrito¹, F. Cozzi¹, M. Bonaldi¹, K. Matiasek², M. Rosati², R. Lombardo^1,3

¹Clinica Neurologica Veterinaria, Milan, Italy, ²Department of Clinical and Comparative Neuropathology, Veterinary Faculty of the Ludwing Maximilians, University of Munich, Munich, Germany, ³Università degli Studi di Milano, Dipartimento VESPA, Milan, Italy

Spinal extramedullary cysts are uncommon causes of myelopathy and are classified in meningeal and extradural non‐meningeal cysts. The former group includes: type I and II extradural and type III intradural meningeal cysts. Type I cysts originate from protrusion of the arachnoid through a dural defect and are subdivided into types IA and IB, their etiology is still unknown and have not been reported in veterinary medicine.

The purpose of this report is to describe a case of type I meningeal cyst in a dog.

A 11‐years‐old female Doberman Pinscher was referred because of tetraparesis. The neuroanatomical localization was cervical spinal cord. MRI of the cervical region showed a rounded non enhancing extradural mass located in the right side of the spinal canal, at the level of C6‐C7. The lesion was hyper‐intense in T2 and STIR sequences, hypointense in T1 sequences. A dorsal laminectomy of C6‐C7 was performed and an extradural mass resembling a cystic lesion with a thin and translucent wall was completely removed. The mass was adjacent to the epidural fat, near but not in relationship with the nerve root and articular processes. Histopathology revealed a fibrocollagenous capsule adjacent to dura mater, associated with aggregates of arachnoidal cells on its inner surface; it was consistent with a type I meningeal cyst. On re‐examination, one month postoperatively, the neurologic conditions improved: the patient was able to stand and walk with a moderately ataxic gait.

This is the first case of type I meningeal cyst in veterinary medicine to the authors knowledge.

MRI assessment of the effect of age on hippocampus height in dogs

A. Gardini, O. Taeymans, A. De Stefani, E. Vettorato, G.B. Cherubini

Dick White Referrals, Six Mile Bottom, Cambridgeshire, UK

Dogs’ hippocampal volume reduction occurs across the adult lifespan. A retrospective study was designed to assess if the height of hippocampus (HH) is affected by ages in dogs and to evaluate the magnitude of this reduction.

Magnetic resonance of dogs brain performed at DWR (2007–2014) were reviewed; 134 studies, in which there was no macroscopic evidence of brain abnormalities, were included. Dogs were divided in two groups: young (1–3 years) and old (>10 years). T2 FLAIR images were analyzed using the same degree of image magnification: the height of the brain (HB) and the height of hippocampus (HH) were measured on a single transverse image containing both the rostral colliculi and mesencephalic aqueduct. HH to brain ratio (HBr) was calculated as (HH/HB)*100. A student t‐test was used to compare HH, HB and HBr between young and old dog (P < 0.05); data were reported as mean (SD).

84 cases were assigned to the young and 50 to the old group. HH was 7.7 (1.2) mm in young and 6.6 (1) mm in old dogs (P < 0.001); HB was 45.3 (3.4) mm in young and 45.5 (4) mm in old animals (P = 0.075). HBr was 17.1 (2.5) % in young and 14.6 (2.5) % in old dogs (P < 0.001).

We demonstrated a statistically significant reduction in HH in older patients. This represents an easy method to evaluate canine hippocampus measurement by a non‐experienced observer who would be able to establish the presence of hippocampal atrophy and to assess its severity in old dogs.

Slit ventricle syndrome and subdural hemorrhage due to suspected overshunting in a dog with hydrocephalus internus

S. Bittermann¹, C. Precht², D. Henke¹, F. Forterre³, P. Karli¹

¹Division of Neurological Sciences, Clinical Veterinary Neurology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Switzerland, ²Division of Clinical Radiology, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Switzerland, ³Division of Small Animal Surgery, Department of Clinical Veterinary Medicine, Vetsuisse Faculty, University of Bern, Switzerland

Overshunting of ventriculoperitoneal (VP) shunts in hydrocephalus patients occurs in 3–5% of people, but is poorly described in dogs.

A 1.5‐year old Chihuahua was presented with clinical signs consistent with multifocal intracranial localization. Magnetic resonance imaging (MRI) findings were compatible with the diagnosis of a hydrocephalus internus and atrophy of the left hippocampus. Following placement of a VP shunt with a low pressure valve in the left ventricle, marked post‐operative improvement was noted. However, clinical signs returned one month later. Cerebrospinal fluid analysis was unremarkable and conservative treatment was unrewarding. A control MRI revealed subdural hematoma, meningeal reaction and slit like ventricles, and was interpreted as overshunting. Saline solution was injected in the ventricles via the shunt, which was then closed by ligation. Clinical improvement was noted, followed again by relapse 3 months later. A third MRI revealed recurrence of the dilatation of the lateral and the third ventricles, residual subdural hemorrhage and meningeal thickening with strong contrast uptake. Owning to the recurrence of hydrocephalus the VP shunt was reconnected and additionally the valve was positioned and fixed in a vertical position. A subcutaneous swelling at the caudal part of the head due to suspected disconnection of the valve occurred two weeks later. The owners elected euthanasia and declined pathological examination.

Complications following VP shunting in this case reveal many similarities to those described in CSF overshunting in people and, although rare, should be considered as a possible complication in dogs following VP shunt placement. The use of middle pressure valves instead of low pressure valves may be beneficial.

Phenobarbitone administration every 8 hours can improve seizure management in idiopathic epileptic dogs with decreased phenobarbitone elimination half life

F. Stabile, L. Sanchez Gallego, L. De Risio

Animal Heath Trust, Newmarket, UK

The purpose of this study was to evaluate safety and efficacy of administration of phenobarbitone every 8 hours (h) in idiopathic epileptic dogs (IED) with decreased phenobarbitone elimination‐half‐life (PBT1/2). Phenobarbitone oral dosage every 12 h (PB0), side effects of treatment and seizure frequency (SF), PBT1/2 when phenobarbitone was administered every 12 h (PBT1/20), phenobarbitone oral dosage every 8 h (PB1), side effects of the treatment and SF, PBT1/2 when phenobarbitone was administered every 8 h (PBT1/21) and administration of additional antiepileptic medications were reviewed in 10 IED in which PBT1/20 was less than/equal to 20 h. PBT1/20 ranged between 7.7 h‐20 h. PB0 ranged from 3.5–8 mg/kg/12 h. SF ranged from a seizure a day for 14 consecutive days to a cluster of three seizures every 6 days. Additional antiepileptic medications included levetiracetam in 2 dogs, potassium bromide and levetiracetam in 4 dogs and levetiracetam as pulsed treatment for cluster of seizures in 1 dog. PB1 ranged from 2.7–5.6 mg/kg/8 h. PBT1/21 was above 30 h (range 20 h‐535 h) in all dogs but one. The PBT1/21 in this dog was 20 h whist PBT1/20 was 7.7 h. All but 1 dog experienced improvement in SF on PB1. Extension of the interictal‐interval greater than 3 times the longest interictal‐interval from seizure‐onset to administration of PB1 was recorded in 8 dogs. Reduction in severity and in clusters of seizures was recorded in 1 dog. In 1 dog SF didn't change but it appeared less sedated, ataxic, poliphagic and polyuric. Administration of phenobarbitone orally every 8 hours in IED with decreased PBT1/2 appears safe and can improve seizure management.

Hypovitaminosis a in a cat: magnetic resonance, computed tomography and histopathological findings

I. Espadas¹, E. Ricci², F. McConnell³, D. Sánchez‐Masián¹

¹Veterinary Neurology and Neurosurgery Small Animal Teaching Hospital, University of Liverpool, Liverpool UK, ²Veterinary Pathology, University of Liverpool, Liverpool UK, ³Diagnostic Imaging, Small Animal Teaching Hospital, University of Liverpool, Liverpool UK

Vitamin A (retinol) is an essential micronutrient that acts as a systemic antioxidant and is involved in the regulation of biological processes including stem cell differentiation, organ development and function, immune system, bone remodeling and vision.

A seven‐year old domestic long hair cat fed a chicken and rice‐based diet, was evaluated for chronic progressive visual impairment and lethargy. Physical and neurological examination revealed cerebellovestibular ataxia and tetraparesis. He was obtunded and had postural reaction deficits in all four limbs. Cranial nerve examination revealed absent menace response and moderately reduced pupillary light reflexes bilaterally. He was visual but was suspected to have difficulty tracking moving objects. Fundoscopic examination showed areas of tapetal hyperreflectivity nasal to the head of the optic nerve He had facial hypoalgesia and significantly reduced corneal reflex bilaterally. The neuroanatomical localization was to the cerebellum/central vestibular system and optic chiasm/retinas and/or optic nerves. Magnetic resonance and computed tomography studies revealed diffuse thickening of the calvarium and tentorium cerebelli with secondary abnormal conformation of the brain. There was mild narrowing of the foramen magnum causing dentation of the caudoventral aspect of the cerebellum. Plasma retinol concentration was 0.1umol/L (reference range 0.86–2.2). Postmortem examination revealed volumetric reduction of the frontal lobes secondary to diffuse skull hyperostosis. Microscopically, there were mild white mater spongiosis affecting the corona radiata and optic nerves and multiple small plaque‐like thickening of the meninges.

Vitamin A deficiency should be considered in the differential diagnosis of cats with progressive history of multifocal intracranial signs (especially visual deficits and cerebellar signs).

Acute ventral cervical spinal cord compression by extrusion of liquid nucleous pulposus in 12 dogs

D. Faissler¹, T. Sutton¹, J. Barker², P. Bain¹

¹Cummings School of Veterinary Medicine at Tufts University, North Grafton, MA 01536, USA, ²Bush Veterinary Neurology Service, Springfield, VA 22150, USA

Hansen type I intervertebral disk disease is characterized by extrusion of cartilaginous and calcified nucleus pulposus. The goal of this study was to describe a series of dogs with spinal cord compressions consisting of a grayish, viscous substance. Inclusion criteria were complete medical history, MRI and visualization of the extruded material at surgery.

Twelve dogs with an average weight of 15.2 ± 9.5 kg and median age of 10.75 years were included. Clinical signs were peracute onset of non‐ambulatory tetraparesis (5/12) or tetraplegia (6/12). One patient exhibited neurogenic respiratory compromise. MRI revealed ventral compressions at C3‐4 (2/12) and at C4‐5 (10/12) with material that was homogeneously hyperintense on T2 and hypointense on T1 weighted sequences. The affected disk showed a partial loss of T2 weighted signal intensity. In 2/12 dogs dog a diffuse, intramedullary T2 weighed hyperintensity was noticed. The estimated spinal cord transverse surface was reduced to 63.7 ± 10.1 % of its original size. After surgical dissection of dorsal annulus fibrosus and longitudinal ligament, leakage of a grayish liquid was observed. One month post‐surgery the neurological status of all dogs had improved.

Cytology of the extruded liquid material was performed in 8 dogs. The analysis showed a basophilic background of a protein rich substance containing microscopic clusters of chondrocytes.

Our hypothesis is that these dogs experienced a sudden rupture of the dorsal annulus fibrosus. The subsequent extrusion of liquid nucleus pulposus caused concussive and compressive spinal cord disease explaining the observed sudden onset, MRI and surgical findings.

MRI findings of dogs with hydrocephalus

N. Tanaka^1,2, D. Ito¹, C. Ishikawa¹, S. Ohta¹, M. Kitagawa¹

¹School of Veterinary Medicine, Nihon University, Kanagawa, Japan, ²Grace Animal Hospital, Tokyo, Japan

Hydrocephalus was a disease with abnormal neurological symptoms resulting from distension of the ventricular system. Diagnosis of hydrocephalus was to find ventriculomegaly by image diagnosis. Recently, magnetic resonance imaging (MRI) is commonly used for the diagnosis. In human, MRI provides characteristic findings of hydrocephalus other than ventriculomegaly (i.e. mamillopontine distance), however there is no information in dogs. Therefore we investigate whether hydrocephalus dogs had these MRI findings.

Five dogs that diagnosed the congenital hydrocephalus at the Nihon University Animal Medical Center were included in this study. The cause of hydrocephalus was diagnosed as aqueduct stenosis in 4 dogs and obstruction of the lateral aperture in remaining dog. Five normal puppies were used as control. We investigate following MRI findings which referred as criteria in human hydrocephalus patients (Gammal TE et al. 1987, Willing SJ. 1995); (1)mamillopontine distance; (2)periventricular interstitial edema; (3)ventricular angle.

Mean VB ratio was 67.2 (59–76) %. mamillopontine distance was 4.3 (1.8–6.8) mm in hydrocephalus dogs, and 3.38 (2.6–4.2) mm in control. Mamillopontine distance tends to reduce in human hydrocephalus patient, but this findings was not commonly seen in dogs. All dogs with hydrocephalus showed periventricular interstitial edema around the anterior horn of lateral ventricle, but all control dogs did not show. Ventricular angle was measured in two dogs with hydrocephalus (8.5, 7.4°). Ventricular angle in normal dogs was mean 33.42 (27.3–37.9°).

Mamillopontine distance was not characteristic findings, but periventricular interstitial edema and decrease of ventricular angle were observed in hydrocephalus dogs similar to human.