くも膜下出血により対側動眼神経麻痺を来した内頚動脈-前脈絡叢動脈分岐部脳動脈瘤の1例

A Case of Contralateral Oculomotor Nerve Palsy due to Internal Carotid Artery-Anterior Choroidal Artery Ruptured Aneurysm

Ⅰ．はじめに

　動眼神経麻痺はさまざまな要因で生じるが，頭痛，頚部痛を伴う突然の動眼神経麻痺は，同側の内頚動脈瘤切迫破裂を示唆する所見として知られており，早急な対応，治療が求められる．今回われわれは，突然の動眼神経麻痺を契機に指摘された，対側の内頚動脈瘤破裂によるくも膜下出血の1例を経験したため，文献的考察を加え報告を行う．

　Sudden oculomotor palsy with severe headache is known to suggest a ruptured ipsilateral internal carotid artery aneurysm. We encountered a case of contralateral oculomotor nerve palsy due to internal carotid artery-anterior choroidal artery ruptured aneurysm. A 63-year-old woman presented with severe headache and sudden right oculomotor palsy. Computed tomography（CT）showed subarachnoid hemorrhage, and three-dimensional CT showed a left internal carotid artery-anterior choroidal artery aneurysm. We performed neck clipping via a left pterional approach. After the surgery, right oculomotor palsy was not observed. We think the causes of oculomotor nerve palsy in this case were hematoma and elevated intracranial pressure. Once these factors were removed, we think that oculomotor nerve palsy was not observed.