(Doctor…My child keeps falling over) unexpected MRI findings in children with history of frequent falls and dizziness: a case series

Abstract

Frequent falls and dizziness are common complaints in children. These symptoms can be caused by wide range of underlying pathologies including peripheral vestibular deficits, cardiac disease, central lesions, motor skills delay and psychogenic disorders. We report three paediatric cases who presented with complaints of repeated falls and imbalance. MRI scan revealed underlying brain lesions (frontal lobe arteriovenous malformation, exophytic brain stem glioma and cerebellomedullary angle arachnoid cyst with cerebellar tonsillar ectopia). By reporting these cases, we would like to emphasise the importance of a thorough assessment of children with similar symptoms by detailed clinical history, physical examination and maintaining low threshold for investigations, including radiological imaging. Taking in consideration, the wide range of differential diagnosis, the challenge of obtaining detailed history and difficulty of performing reliable physical examination in this age group. Management of underlying disorders can be medical, surgical or just observational.

Background

Frequent falls and dizziness are not uncommon complaints in children, but surprisingly there are few articles in the literature discussing this subject. Although the first article reporting dizziness in children was published in 1962,¹ the available data are very variable and limited. The reported prevalence of dizziness and balance disorders in paediatric age group varies between 0.4% and 15%.^{2 3} An epidemiological study showed that 5.7% of the children in UK will experience symptoms of dizziness before or at the age of 10 years.⁴

The extensive differential diagnosis, the unspecificity of the information that can be gathered from the child in most of the cases and the difficulty in obtaining reliable and indicative physical examination findings in young age group, make reaching the accurate diagnosis of the causative aetiology and managing it effectively, a real challenge for any physician. Moreover, 6%–24% of these symptoms can be secondary to psychogenic disorders, with no significant clinical finding.^{5 6}

The peculiarity of this condition can lead either to unnecessary extensive investigations or to overlook serious pathologies like central and cardiac diseases. Therefore, detailed history and meticulous physical examination are the cornerstones in directing the next step in the management to reach the accurate diagnosis and treatment.

Case presentation

All the cases were seen in our specialist paediatric otology clinic in otolaryngology department with complaints of imbalance and frequent falls.

Case 1

A 13-year-old girl referred to the clinic with complaint of dizziness which has been going on since birth, and repeated falls which were noticed 1 year before being assessed in the clinic. She was complaining of headaches, nausea and vomiting. Neuro-otological examination including cranial nerve function and vestibular function tests were normal. Hearing test and audiogram showed normal hearing thresholds on both ears.

Case 2

A 5-year-old girl presented to the clinic with complaints of dizziness, falling over repeatedly, imbalance and speech delay. She had temporal bone fracture subsequent to a fall at the age of 1 year. Neuro-otological examination including cranial nerves and vestibular function was unremarkable. Hearing test and audiogram showed normal hearing levels on both ears.

Case 3

A 6-year-old girl was seen in the clinic for history of clumsiness and regular tripping over which was noticed by her family and reported by the school too. Also, there was a history of symptoms that reflect poor motor coordination like struggling in tying her shoe laces, button and unbutton her shirts and difficulty in going downstairs without holding the staircase. She was under the care of speech and language therapy team in her school due to speech delay. Neuro-otological examination including cranial nerves and vestibular function was unremarkable. Hearing test and audiogram showed normal hearing thresholds on both ears.

Investigations

The order of clinical and radiological exams to be considered in similar cases, depends mainly on the differential diagnosis list that can be formulated after taking the clinical history from the patient and the family. Therefore, it is difficult to formulate a generic rule due to the wide range of possible causes. But when central neurological causes are at the top of the differential diagnosis, then the first-line radiological exam should be the MRI scan and the second one is the CT scan. Due to the fact that the presenting symptoms of the patients were not fully explained by the history and clinical observation, MRI scan of the internal auditory meatus and brain was requested to rule out central and retrocochlear pathology.

Case 1

Magnetic resonance angiography (MRA) and MRI scan showed left frontal lobe arteriovenous malformation (AVM) with feeding vessel from the middle cerebral artery. Spetzler-Martin AVM grade 1. MRI demonstrated normal inner ear structures (figure 1).

Figure 1.

Images showing left frontal lobe arteriovenous malformation (AVM) with feeding vessel from the middle cerebral artery (white arrow). Spetzler-Martin AVM grade 1. (A) Three-Dimensional Maximum Intensity Projection (3D MIP) of the MRA study. (B) MRI scan (T2-weighted image). (C) MRA scan. (D) 3D reconstruction. MRA, magnetic resonance angiography.

Case 2

MRI scan showed focal mass lesion measuring 2.5×1.7×1.5 cm involving the posteroinferior left pons, left middle cerebellar peduncles and posterior left medulla extending posteriorly to the craniocervical junction at the upper cervical cord around the level of C1. Additionally, there was minimal mass effect with compression on the inferior half of the fourth ventricle. Scan suggested the diagnosis of brain stem glioma depending on the radiological appearance of the lesion, with no disseminated disease and normal inner ear structures (figure 2).

Figure 2.

MRI scan showing left side brainstem glioma (white arrow). (A) T2-weighted image. (B) T1-weighted image.

Case 3

MRI scan showed 1 cm left cerebellomedullary angle arachnoid cyst and 7 mm simple pineal cyst without complex features or mass effect and no signs of hydrocephalus (figure 3).

Figure 3.

MRI scan showing left side cerebellomedullary angle arachnoid cyst (white arrow). (A) Axial T2-weighted image showing the cyst. (B) Coronal T2-weighted image showing the extension of the cyst. (C) Axial Fluid Attenuated Inversion Recovery (FLAIR) sequence showing the lesion is suppressing the signal completely. (D) Axial diffuse-weighted imaging showing that there is no restricted diffusion.

Differential diagnosis

Repeated falls and unsteadiness in children can be presenting signs of dizziness and imbalance and they are usually caused either by peripheral, neurological, cardiovascular or psychogenic disorders. Detailed history, associated symptoms and clinical examination can direct the investigation towards one of these categories in most of the cases. In these three cases, the associated presenting symptoms of nausea, vomiting, headache, clumsiness and motor skills delay with the absence of history of cardiac symptoms like syncope, pallor, chest pain, cyanosis or palpitation make the possibility of neurological pathology more likely than the cardiovascular or psychogenic ones. Also, the absence of aural symptoms with normal ear and vestibular function examination, in addition to normal audiological tests, put the peripheral causes down in the list of the differential diagnosis. In view of the history and clinical examination findings, we decided to rule out the possibility of underlying neurological pathology as the next step in our assessment. Therefore, MRI scan was requested, as it is the best and more reliable imaging modality to look for central pathologies which can be vascular, demyelinating, benign or malignant tumours.

Treatment

Case 1

Patient was referred to the paediatric neurosurgery team where she had MRA scan, and she was discussed in the vascular multidisciplinary team meeting. The recommendation was to consider gamma knife treatment with digital subtraction angiography (DSA), as the anomaly is unruptured AVM. Patient underwent stereotactic radiosurgery under general anaesthesia with dose of 25 Gy.

Case 2

Patient was referred to the paediatric neurology team where interval MRI scanning at 1, 3 and 6 months, to monitor the progression or change in the size of the tumour, was performed. Scan that was performed after 6 months showed bulkier tumour compared with the previous scans. In view of these findings, biopsy and partial debulking of the lesion was performed and histopathology sample confirmed the diagnosis of low-grade glial tumour with BRAF V600 mutation. Scan was repeated 1 month after the surgery which showed minimal progression of the tumour at the level of the cervicomedullary junction, so another debulking surgery was performed. Chemotherapy was commenced and 50 cycles of weekly treatment with vincristine (42 mg/m²) and carboplatin (5913 mg/m²) were given.

Case 3

Patient was referred to the paediatric team for further assessment and examination. Her MRI scan findings (arachnoid cyst and pineal cyst) were considered as incidental finding because there was no distortion or mass effect can be seen on the scan that would explain patient’s symptoms. The patient was referred to the physiotherapy team for assessment of her motor skills where she was provided with exercises to strengthen her core muscles.

Outcome and follow-up

Case 1

Treatment was carried out successfully, with follow-up appointment at the neurosurgery department in 6 months and MRI scanning to be repeated in 2 years to look for AVM nidus. If the nidus is not visible on the scan at that time, then DSA will be performed to confirm the obliteration of the lesion.

Case 2

The initial plan was to give 18 months of chemotherapy treatment. MRI scans showed no progression of the tumour over a period of 12 months with clinical improvement, plus the patient developed allergic reactions to the medications, so the decision of stopping the chemotherapy was taken. Clinical and radiological follow-up was arranged with the option of using BRAF inhibitor chemotherapy if signs of progression develop again.

Case 3

Patient was followed up by the paediatric and physiotherapy teams. Improvement was noticed in her clinical symptoms after she practiced the provided exercises. She is currently having regular follow-up in the paediatric clinic.

Discussion

Dizziness in paediatric population can be secondary to different disorders. A dizzy child can presents with wide range of complaints like unsteadiness, frequent falls, abnormal gait, clumsiness, lightheadedness, frequent tripping over with or without other symptoms. These symptoms are essential in minimising the extensive list of the differential diagnosis. Causes of imbalance and dizziness in this age group are different from adult patients. Although middle ear effusion and acute otitis media are among the most common causes of dizziness in children,⁷ but in patients with normal hearing threshold and tympanic membrane examination, migraine and benign paroxysmal vertigo of childhood represent the majority of the causes.5 6 8–13 Psychiatric disorders like depression and anxiety can be important factors, especially in adolescents population.¹⁴ Furthermore, motor and developmental skills delay can be the cause of imbalance and frequent falls in 10.6% of the cases.¹⁵ Least common, but most serious etiologies that need to be ruled out, are the cardiovascular and central neurological diseases.

Despite the fact that dizziness in children can be associated with widely variable symptoms depending on the underlying pathology, headache and nausea are the most common ones.^{7 8} Also, it can be associated with hearing loss, tinnitus, vomiting, pallor, staring, blackouts and others.⁸

The wide spectrum of pathologies that can present with balance disorders make the history, clinical examination and parental observation the most important factors in directing the next step in approaching the final diagnosis. Family history should be inquired, as many balance disorders have a significant genetic association.¹⁵ Neuro-otological examination, motor skills assessment, vestibular function evaluation and hearing test including tympanogram should be considered as part of the initial evaluation. By the end of the primary assessment, a very short differential diagnosis list should be formulated and any further diagnostic steps should be guided by this list to avoid any unnecessary investigations. Further tests should be requested depending on the suspected pathology which can include blood, vestibular, genetic or imaging investigations.

Central lesions should be suspected in cases with long-term history of imbalance, recurrent unexplained witnessed falls with normal neuro-otlogical examination and audiovestibular tests. Utilisation of radiological investigations is important to rule out these lesions. MRI scan is the most sensitive and accurate imaging modality that can be used to rule out central causes when brain lesions are suspected,^{6 7} although sedation is needed in young children.

Multidisciplinary approach is important in the management of a dizzy child due to the different possible causative disorders, which might require the involvement of other specialties like neurology, neurosurgery, paediatrics, audiology, physiotherapy, cardiology, psychiatry, genetics and orthopaedics.¹⁵ Early referral to the paediatric neurology or neurosurgery team is required when central lesion and MRI scan findings is suspected to be the cause of the child’s symptoms, for further assessment and treatment depending on each case clinical presentation and underlying pathology.

It is important to remember that some of these MRI findings are incidental and does not explain the clinical symptoms. So, other possible etiologies should be investigated, and the patient needs to be treated accordingly.

Learning points.

• History and physical examination are the most important part in the assessment of dizziness in children.

• Brain lesions should be ruled out in patients with recurrent falls and normal neuro-otlogical examination, vestibular assessment and audiological tests.

• Low threshold should be maintained for radiological investigations when central neurological lesions are suspected for being the cause of imbalance and dizziness.

• Despite the necessity of sedation in young children, MRI is the most reliable imaging modality when central pathologies need to be investigated.

• Radiological findings should be evaluated carefully, as these findings can be incidental with no clinical significance.

• Multidisciplinary setting is essential in the evaluation and management of dizziness and balance disorders in paediatric population, in view of the wide spectrum of the possible etiologies.