コイル塞栓術を行った遠位上小脳動脈解離性動脈瘤破裂の1例

Ruptured Dissecting Distal Superior Cerebellar Artery Aneurysm Successfully Treated with Coil Embolization:A Case Report

Ⅰ．はじめに

　くも膜下出血のうち原因が解離性動脈瘤破裂によるものは3%程度と報告されている¹⁷⁾．その多くは椎骨動脈，中大脳動脈，内頚動脈などの主幹動脈に発生し，遠位部末梢での報告は少なく，特に上小脳動脈（superior cerebellar artery：SCA）遠位部は稀である．治療法としては，直達手術によるトラッピング，バイパスを併用したトラッピング，体部クリッピングなどが報告されており，血管内治療としては，親血管閉塞，膨隆部塞栓が報告されているが，治療法の選択について確立したものはない．

　今回，くも膜下出血で発症したSCA末梢遠位部の解離性動脈瘤破裂に対して親血管閉塞を含んだコイル塞栓術を行い，良好な転帰を得た症例を経験したので，報告する．

　Background:Ruptured dissecting superior cerebellar artery aneurysms are rare, and only 12 cases have been reported. We report a case of dissecting aneurysm of the distal superior cerebellar artery presenting with subarachnoid hemorrhage.

　Case Presentation:An 80-year-old man presented with a three-day history of headache and diplopia. CT revealed slight subarachnoid hemorrhage and CT angiography demonstrated a dissecting aneurysm located in the distal portion of the left superior cerebellar artery. Initially, we chose conservative therapy. Ten days later, the patient became drowsy. Repeat CT showed that the amount of the subarachnoid hematoma increased and the aneurysm enlarged. Emergent endovascular coil embolization with parent artery occlusion was performed successfully. Postoperative MRI revealed no infarction in the cerebellum or brain stem. Delayed ischemic deficits were not observed after treatment.

　Conclusion:Endovascular parent artery occlusion of the distal superior cerebellar artery is an effective method with low morbidity for treatment of ruptured dissecting distal superior cerebellar artery aneurysms.