Basilar artery fenestration with an associated aneurysm: case report

Cerebral arterial fenestrations

Arterial fenestrations are an anatomic variant with indeterminate significance. Given the controversy surrounding fenestrations we sought their prevalence within our practice along with their association with other cerebrovascular anomalies. We retrospectively reviewed 10,927 patients undergoing digital subtraction angiography between 1992 and 2011. Dictated reports were searched for the terms "fenestration" or "fenestrated" with images reviewed for relevance, yielding 228 unique cases. A Medline database search from February 1964 to January 2013 generated 304 citations, 127 cases of which were selected for analysis. Cerebral arterial fenestrations were identified in 228 patients (2.1%). At least one aneurysm was noted in 60.5% of patients, with an aneurysm arising from the fenestration in 19.6% of patients. Aneurysmal subarachnoid hemorrhage or non-aneurysmal subarachnoid hemorrhage were present in 60.1% and 15.8%, respectively. For the subset of patients with an aneurysm arising directly from a fenestration relative to those patients with an aneurysm not immediately associated with a fenestration, the prevalence of aneurysmal subarachnoid hemorrhage was 66.7% vs. 58.6% (p = 0.58). Fenestrations were more often within the posterior circulation (73.2%) than the anterior circulation (24.6%), though there was no difference in the prevalence of aneurysms within these groups (61.1% vs. 60.7%, p = 1.0). Cerebral arterial fenestrations are an anatomic variant more often manifesting at the anterior communicating arterial complex and basilar artery and with no definite pathological relationship with aneurysms.

Ruptured vertebrobasilar junction aneurysm associated with basilar artery fenestration

A case of a ruptured saccular aneurysm arising from the proximal portion of a partially duplicated basilar artery in a 36-year-old woman is reported. CT and lumbar puncture confirmed subarachnoid haemorrhage. Cerebral angiography detected a vertebrobasilar junction aneurysm associated with basilar artery fenestration. The patient underwent successful clipping and coating of the aneurysm by a right lateral suboccipital osteoclastic approach. Embryological development, pathogenesis, diagnostic and therapeutic difficulties of this vascular malformation are discussed in this report.

Supraclinoid internal carotid artery fenestration with an associated aneurysm. Case report

The case of an aneurysm occurring at the site of fenestration of the supraclinoid portion of the left internal carotid artery (ICA) is reported. A 37-year-old woman presenting with subarachnoid hemorrhage was found to have bilateral ICA aneurysms at the level of the posterior communicating arteries (PCoA's). The patient underwent right-sided craniotomy with uneventful clipping of the right PCoA aneurysm, and attempted clip placement on the contralateral left ICA aneurysm. The follow-up angiogram revealed a residual dome on the left ICA aneurysm, which was noted to originate at the proximal end of a fenestration of the left supraclinoid ICA. This represents the third reported case of fenestration of the intracranial ICA associated with an aneurysm. Intracranial artery fenestrations and their embryological origins are also reviewed.

Aneurysm of the fenestrated basilar artery: report of two cases

This report describes two patients with fenestrated basilar artery aneurysms, and one of the patients underwent a postmortem examination. In our cases, the aneurysms arose at the proximal end of the fenestration, which involved the proximal third of the basilar artery. Subtraction angiography and oblique projections were essential in diagnosing the aneurysms. Complete neck clipping was successfully performed through a lateral suboccipital approach in the two cases. Technical aspects of neck clipping of the aneurysm of this unique location are discussed. Pathogenesis of these rare aneurysms is also discussed with clinical and histopathological data.

Cerebral arterial fenestrations associated with intracranial saccular aneurysms

Fenestrations of cerebral arteries other than the anterior communicating artery are rare congenital anomalies, which may be associated with saccular aneurysms. In such cases, the aneurysms may be located at the fenestration itself or may involve other intracranial vessels. This kind of association is not infrequently the cause of angiographic diagnostic problems, as well as surgical difficulties, and consequently needs to be well known to physicians. Four recent cases of rare fenestrations of cerebral arteries associated with intracranial aneurysms are reported in this study and discussed together with a review of the literature.

Duplication of the vertebro-basilar system

During the examination of 75 fixed brains and 2086 vertebral angiograms we encountered two cases of fenestration of the vertebral artery and two cases of partial duplication of the basilar artery. In the first case, an 81 year old male, there was fenestration, of the basilar artery at the union of the two vertebral arteries. The fenestration was 9mm long with no associated vascular disease. The other partial duplication of the basilar artery was observed in the upper portion of the artery in a 54 year old male patient investigated angiographically for subarachnoid haemorrhage. The fenestration of the third case was demonstrated in the intracranial part of the right vertebral artery of a 50 year old female patient during digital subtraction angiography for subarachnoid haemorrhage. In the fourth case, the fenestration was found angiographically at the atlanto-axial level in the extracranial portion of the left vertebral artery in a 37 year old female patient with subarachnoid haemorrhage from an arteriovenous malformation in the left cerebral hemisphere. The embryonic, histological and radiological implications of the duplication are discussed.