Fujimura Miki, Inoue Takashi, Shimizu Hiroaki, Tominaga Teiji
Department of Neurosurgery, Kohnan Hospital, Sendai, Miyagi, Japan.
Neurol Med Chir (Tokyo). 2012;52(6):435-8. doi: 10.2176/nmc.52.435.
A 77-year-old woman presented with an extremely rare exclusively intra-meatal anterior inferior cerebellar artery (AICA) aneurysm manifesting as subarachnoid hemorrhage. The aneurysm was located at a non-branching site of its meatal loop, deeply inside the internal auditory canal. The ipsilateral posterior inferior cerebellar artery was hypoplastic and the affected AICA supplied a wide vascular territory in the right cerebellum. The patient underwent microsurgical trapping of the distal AICA aneurysm in the acute stage. Collateral back flow to the parent artery was poor, so right occipital artery (OA)-AICA anastomosis was performed prior to aneurysm trapping. The postoperative course was uneventful, and magnetic resonance imaging after surgery did not demonstrate any ischemic change. Postoperative angiography showed complete disappearance of the AICA aneurysm and the apparently patent OA-AICA bypass. She did not suffer neurological deficit except for right incomplete hearing disturbance, and postoperative single photon emission computed tomography demonstrated absence of hemodynamic compromise in the cerebellum. OA-AICA anastomosis with aneurysm trapping could be the optimal surgical management of the AICA aneurysm located exclusively inside the internal auditory canal, especially if the parent artery supplies a wide vascular territory.
一名77岁女性因极其罕见的仅位于内听道内的前下小脑动脉（AICA）动脉瘤破裂导致蛛网膜下腔出血前来就诊。该动脉瘤位于其内听道袢的非分支部位，深埋于内听道内。同侧后下小脑动脉发育不良，受累的AICA为右侧小脑的广泛血管区域供血。患者在急性期接受了AICA远端动脉瘤的显微手术夹闭。向母动脉的侧支回流较差，因此在动脉瘤夹闭前进行了右枕动脉（OA）-AICA吻合术。术后病程平稳，术后磁共振成像未显示任何缺血改变。术后血管造影显示AICA动脉瘤完全消失，且OA-AICA搭桥明显通畅。除了右侧不完全听力障碍外，她没有出现神经功能缺损，术后单光子发射计算机断层扫描显示小脑无血流动力学受损。对于仅位于内听道内的AICA动脉瘤，尤其是当母动脉为广泛血管区域供血时，OA-AICA吻合术联合动脉瘤夹闭可能是最佳的手术治疗方法。
