破裂前交通動脈瘤の治療に対するクリッピング術とコイル塞栓術の症例分配について

Case Allocation in the Management of Ruptured Anterior Communicating Aneurysm Using Endovascular Embolization as a First Option

Ⅰ．はじめに

　International Subarachnoid Aneurysm Trial（ISAT）の研究結果は，これまで主に開頭手術で行われてきた破裂前交通動脈瘤の治療にコイル塞栓術という選択肢を加えた^12,13,21)．しかし，ISATの結果を一般化しコイル塞栓術を第一選択とすることには批判もあり，破裂前交通動脈瘤は，pterional approachで開頭手術を第一選択として行っている施設が大多数と思われる^4,5,17)．開頭手術，血管内治療それぞれの利点を高め，リスクを最小限にとどめるような症例の選択を具体的にどうすべきかは不明確である^{7,15,18,19,21)}．

　われわれは2004年4月より破裂動脈瘤は“コイル塞栓術”“開頭手術”それぞれの治療を専門とする医師が動脈瘤の形状，病態を考慮し治療法を決定し，いずれの方法でも治療可能と判断された場合にはコイル塞栓術を第一選択とする方針を採用した¹³⁾．今回，2004年以後の当院における破裂前交通動脈瘤の治療現状を，decision-making processと各治療に分配される頻度についてretrospectiveに検討し両治療の適切な選択に関する考察を行った．

　Objective: The management of ruptured anterior communicating aneurysms remains controversial since the results of ISAT have been reported. The aim of our study is to report our decision-making process and outcome in 36 consecutive cases using endovascular coil embolization as a first choice of treatment.

　Patients and methods: Thirty-six patients were studied. Since April, 2004, the treatment modality has been decided after discussion between the endovascular and cerebrovascular surgeons, taking into account the physiological status, treatment risk and morphology of the aneurysm.

　Results: Twelve (33%) of 36 patients were allocated to coil embolization. Factors leading to the selection of clipping surgery were decided mostly by the morphology of the aneurysm, namely, tiny in 11 (47.8%), irregular shape in 6 (26.1%), broad neck in 3 (13.0%) and bleb located at the neck in 3 (13.0%). Half of the aneurysms projecting anteriorly were treated by coil embolization.

　Conclusion: The allocation rate of endovascular treatment in ruptured anterior communicating aneurysms was 33%. Endovascular treatment was effective in at least half of the anterior the projecting aneurysms.