Abstract
Background
Cerebrovascular lesions are uncommon in neurofibromatosis type 1 (NF1).
Case Description
We report a case of 34-year-old man with NF1 who developed posterior circulation stroke. Diffusion-weighted imaging showed acute infarcts in the right vertebra basilar artery territory. Digital subtraction angiography demonstrated significant stenosis of the basilar artery in the mid segment that was identified as the etiology of the symptoms. The vertebral arteries were tortuous and the basilar artery was ectatic. Subsequently endeavour resolute stent was placed across the lesion and post-procedure angiogram showed resolution of stenosis.
Conclusion
Selective stenotic involvement of the basilar artery with ectatic vertebrobasilar circulation associated with NF1, which was successfully treated with endovascular method, was not been reported previously to our knowledge.
Keywords: basilar artery, neurofibromatosis, stent, stroke
Introduction
Neurofibromatosis type 1 (NF1) is a genetic disorder that produces a broad spectrum of clinical manifestations as a result of abnormal growth of neuroectodermal tumors throughout the body. It is a genetic disorder, caused by a mutation in the NF1 gene on chromosome 17 [1]. The most common manifestation of NF1 vasculopathy is renal artery dysplasia and hypertension. Cerebrovascular abnormalities in NF1 are uncommon manifestations. Neurofibromin, the protein product of the NF1 gene, expressed in endothelial and smooth muscle cells of blood vessels [2], is lost in NF1 which increases the proliferation of vascular smooth muscle cells with subsequent intimal proliferation and arterial stenosis. We report a case of posterior circulation ischemic stroke caused by basilar artery stenosis in an Asian man with NF1, treated successfully with percutaneous transluminal angioplasty and stenting. This is an unusual clinical presentation in NF1 with only involvement of the basilar artery and no other vascular involvement.
Case report
A 34-year-old man with no previous history of any medical illness presented with recurrent symptoms of ataxia, dizziness, and imbalance from past 3 months. The frequency of these symptoms was increasing despite the continuous medical treatment (Plavix 75 mg and Ecospirin 75 mg). On clinical examination, he has multiple neurofibromas (Figure 1) predominantly involving the joints. Magnetic resonance imaging (MRI) of the brain showed foci of restricted diffusion in the right vertebrobasilar artery territory suggestive of acute infarcts. Three-dimensional (3-D) time-of-flight MR angiography showed ectatic basilar with stenosis in the mid basilar segment (Figure 2). Digital subtraction angiography done subsequently showed tortuous vertebral arteries and the ectatic basilar artery with significant flow limiting stenosis in the mid segment (Figure 3A). In view of the increasing frequency of the symptoms despite the optimum medical management, endovascular treatment was planned.
Figure 1. Cutaneous neurofibromas seen involving the hand, foot, and the elbow joint regions.
Figure 2. MRI (A) demonstrates the acute infarcts (arrows) in the right vertebrobasilar artery territory. MR angiogram (B) showing the ecstatic basilar artery (double-lined arrow) with mid segment stenosis (single arrow ).
Figure 3. Angiogram demonstrates the stenotic lesion (arrow in A). Drug eluting stent was placed across the lesion (arrow in B). Post-procedure angiogram with good flow across the stented segment (C and D).
Under general anesthesia, right common femoral was accessed. Standard heparinization was given to maintain the activated clotting time of ~250 s. Guide catheter (5F Envoy, cordis) was placed in the left vertebral artery (with Nimodipine infusion). The stenotic segment of the ectatic basilar artery was crossed using a 0.014 microwire. Subsequently, drug eluting stent (Endeavour) was placed across the lesion (Figure 3B). Post-stent angiogram showed resolution of the stenosis with good ante grade flow across the treated segment (Figure 3C and D).
The intra- and periprocedural periods were uneventful. The patient did not have any further episodes of transient ischemic attacks and was discharged on dual antiplatelet (Ecospirin 75 mg and Plavix 75 mg). On 1-month clinical followup, neurological examination was normal.
Discussion
NF1 present frequently with “cafe au lait” spots and neurofibromas. Vasculopathy in NF1 commonly involves the renal arteries but cerebrovascular involvement can occur.
Neurovascular abnormalities in NF1 are rare. The various abnormalities in NF1 include steno-occlusive disease, arteriovenous fistula, and aneurysm formation [3].
Mitsui et al reported a case of the basilar artery fusiform aneurysm manifesting as Wallenberg’s syndrome in a patient with NF1 [4]. In our present case, the vertebrobasilar circulation was ectatic and the patient did not have any other risk factors for atherosclerosis. Ectasia of the vertebrobasilar artery system was defined as arterial diameter 4.5 mm in any location along its course [5]. The cerebrovascular alterations in NF1 are usually asymptomatic, with few cases of ischemic stroke being reported [6]. The most common form of cerebral vasculopathy in NF1 patients is occlusive disease, usually occurring in childhood or adolescence and often associated with a moya moya pattern of collateral blood flow [3] which was not seen in our case. The supraclinoid portion of the internal carotid artery is the segment most frequently involved in the occlusive disorder. Primary involvement of the anterior and middle cerebral arteries is common. Bilateral internal carotid angiograms were normal with normal anterior and middle cerebral arteries in our case. Involvement of the posterior circulation alone is less frequent as seen in the present case. In the literature review, we did not find such a case in adults with stroke in stenotic disease. Piovesan et al [6] reported a case of stroke and the basilar artery impression in NF1. Moya moya syndrome was seen in their case. Cases of vertebral arteriovenous fistulae and aneurysms treated by endovascular method were reported [7]–[13]. Partha et al in their study assessed the prevalence, clinical manifestations, and outcome of cerebral vasculopathy in children with NF1 in children. They found vasculopathy in 4.8% of children and none of children had neurologic deficits. Moya moya pattern was seen in seven patients and occlusive disease is seen in the rest of the patients [14].
We did not find any reports of treatment of intracranial arterial stenotic disease associated with NF1. The present case report is unique because of the unusual clinical manifestation in middle-aged man with NF1, the ectatic basilar artery with segmental flow limiting stenosis which was successfully treated with endovascular treatment.
Table 1. Review of previously reported cases of NF1 with cerebrovascular disease.
| No. | Study | Demographics (M: male; F: female | Presentation | Cerebrovascular Manifestations |
|---|---|---|---|---|
| 1 | Mitsui et al [4] | 49 M | Atypical Wallenbergs syndrome | Fusiform aneurysm of the mid basilar artery along with enlarged basilar artery. |
| 2 | Piovesan et al [6] | 51 M | Stroke | Proximal stenosis of right internal carotid artery, moya moya vessels in posterior fossa with occlusion of bilateral vertebrals. Basilar artery impression. |
| 3 | Partha et al [14] | 7 F and 8 M in pediatric age group | No neurological deficit | Moya moya pattern in seven cases and occlusion of major arteries in eight cases |
| 4 | Pereira et al [11] | 49 F | Neck pain and torticolis | Vertebrovertebral arteriovenous fistula |
| 5 | Pereira et al [11] | 45 M | Cervical bruit, retroauricular pain, and progressive parapresis | Vertebrovertebral arteriovenous fistula |
| 6 | Pereira et al [11] | 48 M | Cervical bruit and right cervical pain radiating to the right arm | vertebrovertebral arteriovenous fistula |
| 7 | Pereira et al [11] | 14 F | Radiculopathy | Right vertebral aneurysm at the C5–C6 level |
| 8 | Miyazaki et al [12] | 52 F | Neck pain, monoparesis, and somnolence | Left vertebral artery aneurysm |
| 9 | Myung Won You et al [13] | 16 M | Visual disturbance for 1 year | Fusiform aneurysms from bilateral extracranial internal carotid arteries |
| 10 | Present case | 35 M | Posterior circulation stroke | Stenotic lesion in mid basilar artery segment with ecstatic basilar artery treated by drug eluting stent |
References
- 1.Fortman BJ, Kuszyk BS, Urban BA, Fishman EK. Neurofibromatosis type 1: a diagnostic mimicker at CT. Radiographics. 2001;21:601–12. doi: 10.1148/radiographics.21.3.g01ma05601. [DOI] [PubMed] [Google Scholar]
- 2.Rosser TL, Vezina G, Packer RJ. Cerebrovascular abnormalities in a population of children with neurofibromatosis type 1. Neurology. 2005;64:553–55. doi: 10.1212/01.WNL.0000150544.00016.69. [DOI] [PubMed] [Google Scholar]
- 3.Schievink WI, Riedinger M, Maya MM. Frequency of incidentalintracranial aneurysms in neurofibromatosis type 1. Am J MedGenet A. 2005;134A:45–8. doi: 10.1002/ajmg.a.30475. [DOI] [PubMed] [Google Scholar]
- 4.Mitsui Y, Nakasaka Y, Akamatsu M, Ueda H, Kihara M, Takahashi M. Neurofibromatosis type 1 with basilarBasilar Artery fusiform aneurysm manifesting Wallenberg’s syndrome. Intern Med. 2001;9:948–51. doi: 10.2169/internalmedicine.40.948. [DOI] [PubMed] [Google Scholar]
- 5.Ubogu EE, Zaidat OO. Vertebrobasilar artery dolichoectasia diagnosed by magnetic resonance angiography and risk of stroke and death: a cohort study. J Neurol Neurosurg Psychiatry. 2004;75:22–6. [PMC free article] [PubMed] [Google Scholar]
- 6.Piovesan EJ, Scola RH, Werneck LC, et al. Neurofibromatosis, stroke and basilar artery impression. Case report. Arq Neuropsiquiatr. 1999;57:484–8. doi: 10.1590/s0004-282x1999000300022. [DOI] [PubMed] [Google Scholar]
- 7.Hori Y, Goto K, Ogata N, Uda K. Diagnosis and endovascular treatment of vertebral arteriovenous fistulas in neurofibromatosis 1. Intervent Neuroradiol. 2000;6:239. doi: 10.1177/159101990000600310. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Ma X, Aminima M, Rozen TD. Arteriovenous fistula in neurofibromatosis. Neurology. 2000;55:288. doi: 10.1212/wnl.55.2.288. [DOI] [PubMed] [Google Scholar]
- 9.Tanaka T, et al. Combination of intravascular surgery and surgical operation for occipital subcutaneous arteriovenous fistula in a patient with neurofibromatosis type I. No Shinkei Geka. 2002;30(3):309–13. [PubMed] [Google Scholar]
- 10.Kahara V, et al. Vertebral epidural arteriovenous fistulaand radicular pain in neurofibromatosis type I. ActaNeurochir (Wien) 2002;144:493–6. doi: 10.1007/s007010200071. [DOI] [PubMed] [Google Scholar]
- 11.Pereira VM, Geiprasert S, Krings T, et al. Extracranial vertebral artery involvement in neurofibromatosis type I. Report of four cases and literature review. Interv Neuroradiol. 2007;13:315–28. doi: 10.1177/159101990701300402. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Miyazaki T, et al. 2004Extracranial vertebral artery aneurysm ruptured into the thoracic cavity with neurofibromatosis type 1: case report Neurosurgery 541517–20.; discussion 1520, 1 [DOI] [PubMed] [Google Scholar]
- 13.Myung Won You, Eui Jong Kim, Woo Suk Choi. Intracranial and extracranial fusiform aneurysms in a patient with neurofibromatosis type 1: a case report. Neurointervention. 2011;6:34–7. doi: 10.5469/neuroint.2011.6.1.34. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Partha S. Ghosh, David Rothner A, Todd M. Emch, et al. Cerebral vasculopathy in children with neurofibromatosis type 1. J Child Neurol. 2012 doi: 10.1177/0883073812441059. doi:10.1177/0883073812441059. [DOI] [PubMed] [Google Scholar]