Posterior Inferior Cerebellar Artery Excision and End-to-End Reanastomosis for Treatment of a Giant, Partially Thrombosed Aneurysm: 2-Dimensional Operative Video

Abstract

Aneurysms of the anterior inferior cerebellar artery-posterior inferior cerebellar artery (AICA-PICA) anatomic variants with a single trunk arising from the basilar artery supplying the AICA and PICA territories are relatively rare. 1,2 Large aneurysms in this region, particularly those that are partially thrombosed, may mimic other pathologies such as tumors and highlights the importance of vascular imaging as part of the workup. 3,4 Aneurysm excision with end-to-end reanastomosis in the PICA territory is a viable treatment modality for aneurysms that are unable to be treated with endovascular techniques or primarily clipped without putting the distal vascular territory at risk. 5,6 We demonstrate the technique of aneurysm excision and vessel reimplantation for the treatment of an unruptured, giant, partially thrombosed PICA aneurysm along with AICA-PICA variant anatomy found in a 42-year-old man. The patient consented to the procedure and the publication of his image. Safe occlusion of the aneurysm was not felt to be possible with endovascular treatment or with primary microsurgical clipping without resulting in a proximal PICA stroke because of the aneurysm's dysplastic neck. It was felt that aneurysm excision with vessel reanastomosis was the most appropriate management option to preserve blood supply in the distal vascular territory, exclude the aneurysm from the cerebral circulation, and decrease the aneurysm's mass effect on the surrounding brainstem. The redundancy of the PICA segments allowed for the successful creation of an in-situ end-to-end reanastomosis. Aneurysm excision and reanastomosis is an effective treatment strategy for select complex aneurysms.