Perforator aneurysms of the posterior circulation: case series and review of the literature.

Introduction: Posterior circulation perforator artery aneurysms are sparsely reported in the literature. The natural history of these rare lesions remains unclear and their diagnosis and management are not well-defined.

Methods: We reviewed our institution's medical records and performed a comprehensive literature search for cases of posterior circulation perforator aneurysms. Diagnostic imaging, management and clinical outcomes were the primary components of interest.

Results: Our first case was a 58-year-old patient who developed an infarct after attempted endovascular treatment of a basilar perforator artery aneurysm, the second case was a 55-year-old patient with a posterior cerebral artery perforator aneurysm who did well with conservative management and the third case was a 68-year-old patient who suffered an infarct after successful Onyx embolization of a superior cerebellar artery perforator aneurysm. From the literature we identified four case reports and four case series, all describing aneurysmal lesions of the basilar perforator arteries, giving a total of 17 cases including those from our institution. All cases presented with subarachnoid hemorrhage although 47% of initial vascular imaging studies failed to reveal the aneurysm. Cumulatively, 41% of patients were treated with microsurgery, 35% were treated with endovascular therapy and 24% were managed conservatively with subsequent spontaneous aneurysm resolution at a mean interval of 10 months after rupture.

Conclusions: Perforator aneurysms of the posterior circulation are diagnostic and therapeutic challenges. Both microsurgical and endovascular treatment of posterior circulation perforator aneurysms are technically difficult, necessitating comprehensive management by an experienced cerebrovascular team.