1) craniocaudal (high or low riding)
2) mediolateral-premeatal (proximal)
3) meatal-postmeatal (distal).
The management strategies for treatment differ according to the location and configuration of the aneurysm. The existing body of neurosurgical literature contains articles published on aneurysms arising from the AICA near the basilar artery (BA), intracanalicular/meatal aneurysms, and distal AICA. Several therapeutic options exist, encompassing microsurgical and endovascular techniques.
Bambakidis et al. describe a case of treatment involving a large BA-AICA aneurysm approached via exposure of the presigmoid dura using a retromastoid suboccipital craniectomy and partial petrosectomy. Treatment of these lesions requires detailed knowledge of the anatomy, and an anatomical overview of the AICA with its arterial loops and significant branches is presented, including a discussion of the internal auditory artery, recurrent perforating arteries, subarcuate artery, and cerebellosubarcuate artery. The authors discuss the various surgical approaches (retromastoid, far lateral, subtemporal, and transclival) with appropriate illustrations, citing the advantages and disadvantages in accessing these AICA lesions in relation to these approaches. The complications of these different surgical techniques and possible clinical effects of parent artery occlusion during AICA surgery are highlighted. 1)
Aneurysms arising from the midbasilar trunk are not common, and surgical management of these aneurysms remains a difficult challenge to neurosurgeons because of its anatomic characteristics. A patient with a ruptured aneurysm arising from the basilar artery at the origin of the anterior inferior cerebellar artery and projecting to the right and upward. The aneurysm was successfully treated by a subtemporal transpetrosal approach in an acute stage 2).
Distal anterior inferior cerebellar artery (AICA) pseudoaneurysms are very rare lesions. Although cases have been previously reported, only a few have been reported as a result of vestibular schwannoma (VS) radiation, none have been reported as a result of VS resection, and only one has been reported as treated with parent vessel occlusion (PVO) with n-butyl cyanoacrylate (nBCA) 4).
Sato S, Adachi H, Imamura H, Sakai N, Tani S, Narumi O, Sakai C, Arimura K, Morimoto T, Shibata T, Agawa Y, Shimizu K, Kikuchi H. [A Case of Stent-Assisted Coil Embolization for Ruptured Anterior Inferior Cerebellar Aneurysm after Iatrogenic Vertebral Arteriovenous Fistula]. No Shinkei Geka. 2017 Nov;45(11):997-1002. doi: 10.11477/mf.1436203635. Japanese. PubMed PMID: 29172206 5).