|Year : 2021 | Volume
| Issue : 1 | Page : 38-40
Endovascular treatment of a saccular aneurysm associated with fenestrated basilar artery and proximal stenosis of vertebral artery origin - A treatment challenge
Himanshu R Patel, Barve S Pandurang, Trimurti D Nadkarni
Department of Neurosurgery, Topiwala National Medical College, B.Y.L. Nair Ch. Hospital, Mumbai, Maharashtra, India
|Date of Submission||21-Nov-2020|
|Date of Decision||01-Jun-2021|
|Date of Acceptance||18-Jul-2021|
|Date of Web Publication||27-Aug-2021|
Dr. Trimurti D Nadkarni
Department of Neurosurgery, Topiwala National Medical College, B.Y.L. Nair Ch. Hospital, Mumbai, Maharashtra
Source of Support: None, Conflict of Interest: None
A 52-year-old woman had subarachnoid haemorrhage due to an aneurysm at a fenestration of the vertebrobasilar artery junction. The fenestration and aneurysm filled by the dominant left vertebral artery (VA). The left VA had a tight stenosis at its origin from the left subclavian artery. The patient underwent a stent-assisted coiling of the aneurysm after balloon dilatation of the proximal stenosis. The management of this unusual and rare entity is discussed. The relevant literature on the subject is presented.
Keywords: Basilar artery fenestration, endovascular treatment, stent-assisted coiling, three-dimensional rotational angiography
|How to cite this article:|
Patel HR, Pandurang BS, Nadkarni TD. Endovascular treatment of a saccular aneurysm associated with fenestrated basilar artery and proximal stenosis of vertebral artery origin - A treatment challenge. J Cerebrovasc Sci 2021;9:38-40
|How to cite this URL:|
Patel HR, Pandurang BS, Nadkarni TD. Endovascular treatment of a saccular aneurysm associated with fenestrated basilar artery and proximal stenosis of vertebral artery origin - A treatment challenge. J Cerebrovasc Sci [serial online] 2021 [cited 2021 Dec 1];9:38-40. Available from: http://www.jcvs.com/text.asp?2021/9/1/38/324816
| Introduction|| |
Fenestration of the basilar artery is rare and occurs most frequently at its proximal third. The detection of fenestration of basilar artery depends on the radiological technique used namely 0.5% at angiography, 2% on magnetic resonance angiography and up to 5% at autopsy. Saccular aneurysms of the vertebrobasilar junction are rare and they are often associated with fenestration of the basilar artery. Fenestration occurs due to failure of fusion plexiform primitive longitudinal neural arteries. The complex anatomy of the brainstem region makes endovascular treatment the first choice in most cases. The aim of our case study is to report the management of a patient with fenestrated basilar artery and saccular aneurysm with proximal left side vertebral artery (VA) origin stenosis.
| Case Report|| |
A 52-year-old woman presented with sudden onset of severe headaches and giddiness followed by vomiting and loss of consciousness for 48 h. Computed tomography (CT) of the brain showed subarachnoid haemorrhage in bilateral Sylvian fissures, prepontine and basal cisterns. CT Angiogram of intracranial arteries showed a fenestration at the left vertebrobasilar artery junction. There was a 4 mm × 4 mm aneurysm on the left arm of the basilar fenestration. On digital subtraction angiography both the aneurysm and fenestration opacified only on the left VA injection [Figure 1]. There was no filling of the aneurysm or evidence of a fenestration on the right VA injection [Figure 2]. A significant left VA stenosis was noted at its origin from the left subclavian artery. A three-dimensional rotational angiography (3DRA) was performed to further delineate the anatomy of the aneurysm and its relation to the fenestration.
|Figure 1: Digital subtraction angiography left vertebral artery injection showing a saccular aneurysm at vertebrobasilar fenestration|
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|Figure 2: Digital subtraction angiography right vertebral artery injection demonstrates that the vertebrobasilar fenestration and aneurysm do not fill from the right vertebral artery|
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The ruptured aneurysm was treated by a stent-assisted coiling method. It was decided to approach the aneurysm from the left VA as this vessel was dominant and the aneurysm was on the left side of the fenestration. Because of the marked stenosis at left VA origin, the left VA stenosis was dilated by balloon angioplasty (Sprinter Legend Rx 3.5 mm × 12 mm) [Figure 3]. Post-angioplasty, a 6F guiding catheter (Envoy) was easily negotiated into the distal left VA. A microcatheter (SL 10) was negotiated into the aneurysm and jailed by deployment of stent. A stent (Neuroform Atlas More Details 3 mm × 21 mm) was deployed across neck of aneurysm from the left arm of the fenestration to the left VA. The stent's distal end was just proximal to the origin of the left anterior inferior cerebellar artery (AICA) and its proximal end in left VA [Figure 4]. The aneurysm was coiled using three coils through the jailed microcatheter. The coils used were as follows Target 360 soft 3 × 6, Target 360 soft 2.5 × 6 and Target Helical Ultra 2 × 4. A check angiogram showed complete occlusion of the aneurysm with patency of the left fenestration parent branch [Figure 5]. The patient had an uneventful post-procedure recovery. The patient was discharged on dual anti-platelets therapy. She was asymptomatic on 3 months' follow-up.
|Figure 3: Digital subtraction angiography left vertebral artery origin (a) Pre-angioplasty; (b) Post-angioplasty|
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|Figure 4: Plain anteroposterior radiograph of skull shows the deployed intracranial stent (arrows)|
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|Figure 5: Digital subtraction angiography left vertebral artery injection shows complete coiling of the aneurysm with patency of the fenestration|
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| Discussion|| |
The basilar artery is the second-most common site of intracranial fenestration, after the anterior communicating artery. Fenestration of the basilar artery is most common in the proximal portion near the vertebrobasilar artery junction. Conversely, fenestration of the middle and distal portions of the basilar artery is not common and fenestration of the basilar artery with an aneurysm is rare.
The basilar artery is formed by fusion of the plexiform primitive longitudinal neural arteries in a craniocaudal direction by approximately the fifth foetal week. If these embryonic precursors fail to fuse completely, duplication or fenestration of the basilar artery results.
There is an increased incidence of aneurysm formation at the site of fenestration, presumably due to abnormal flow dynamics. They are reported in 7% of fenestrations. Medial defects, are a common feature in both intracranial arteries and fenestrations, which may pre-dispose the arterial fenestration to aneurysm formation.
A meticulous pre-procedural planning is extremely important to study the exact anatomy of the aneurysm-fenestration complex to determine the most appropriate endovascular therapeutic technique. To achieve this, a 3DRA is an extremely helpful tool as was done in our case.
Decision making for endovascular coiling of this type of aneurysm is also dependent on the relationship between AICA or posterior inferior cerebellar artery (PICA) and the fenestration loop. If the AICA or PICA does not originate from the fenestration loop, one side of the fenestration loop of the VA can be occluded safely if warranted.
Intracranial stenting or stent-assist coil embolisation of unruptured aneurysms requires sufficient pre-medication with an antiplatelet agent, mainly P2Y12 blocker, such as clopidogrel. Before stenting procedures, a therapeutic serum level of an ingested drug can be checked by platelet function assay.
Several endovascular techniques described could be adopted to treat aneurysms at fenestrations, including simple coiling, balloon remodelling, stent-assisted coiling and flow diversion devices. Our literature review shows that the majority of the fenestrated basilar artery aneurysms were treated with simple coiling (78.2%), even those with wide necks. This could be explained because many of these patients were treated before the development of the balloon remodelling and the stent-assisted coiling techniques.,
The endovascular technique used in the reported case highlights the efficacy of stent-assisted coiling in such cases. The need for balloon angioplasty for the proximal VA stenosis was necessary to permit access to the aneurysm. However, this step added to the complexity of the procedure with due risks.
| Conclusion|| |
Vertebrobasilar junction aneurysms associated with fenestrations are rare. Stent-assisted coiling technique of such an aneurysm offers complete cure.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]