Dissecting anterior inferior cerebellar artery aneurysm treated by endovascular route: report of three cases and review.

ANGIORAD, Interventional Radiology, Hospital Santa Joana, Recife PE, Brazil: Interventional Radiologist, Scientific Director of ANGIORAD; Neurosurgeon, Hospital da Restauração, Recife PE, Brazil; Chaiman of the Department of Neurosurgery, Hospital da Restauração, Recife PE, Brazil; Resident of Neurosurgery, Hospital da Restauração, Recife PE, Brazil; Resident of Interventional Radiology, ANGIORAD; Interventional Radiologist, Chairman of ANGIORAD. Among the major arteries of the posterior fossa, the anterior inferior cerebellar artery (AICA) is the least likely to harbor an aneurysm, being a very rare pathology. Only two AICA aneurysms were found in 7,933 lesions. In the presence of a high flow lesion, aneurysms tend to occur more commonly in the feeding arteries. These flow-related aneurysms in the posterior fossa can be found mainly associated with arteriovenous malformations (AVM) or hemangioblastomas, which represents the majority of AICA aneurysms reported. For eight years, 1,450 aneurysms were seen in a single-center, with only two AICA aneurysms, both flow-related (AVM). Aside from flow-related aneurysms, almost all distal AICA aneurysms are dissecting aneurysms, usually presenting in otherwise healthy adults. Again the AICA is the least likely to present an isolated dissection among the major arteries. We report three cases of “spontaneous” AICA dissection aneurysms.