Neurological Surgery 脳神経外科37巻4号

2009年04月発行

連載 脳神経外科疾患治療のスタンダード

5．未破裂脳動脈瘤の治療―脳ドックのガイドライン2008を中心に

著者： 森田明夫¹ 木村俊運¹ 楚良繁雄¹

所属機関： ¹NTT東日本関東病院脳神経外科

ページ範囲：P.399 - P.411

Ⅰ．はじめに

　未破裂脳動脈瘤の治療方針の決定は難しい．その理由は第1に未破裂脳動脈瘤の自然歴が個々の瘤に関しては不明なこと⁵⁴⁾，第2に治療リスクが報告によってかなり異なり，動脈瘤の部位や大きさ，患者の状況によっても施設ごとで治療成績に差があること^56,63)，また3つ目には，治療は予防治療の色合いが濃く，その意義について患者と医療側の考えに大きな差がありうること^3,27)，もし何らかの合併症を併発すると訴訟を含めた問題となりうることなどである．また破裂率の高い瘤ほど治療のリスクも高いという大きな問題がある．

　現在日本では，年間1万例超の未破裂脳動脈瘤患者が開頭クリッピングまたは血管内コイル治療のいずれかを受けている．社団法人日本脳神経外科学会調べでは2006年には日本全国で8,839件の開頭クリッピング術，3,053件のコイル塞栓術が施行されている（http://ucas-j.umin.ac.jp/UCAS2007/index.html）．このような治療の根拠を明らかとし，医療者としてしっかりとした基準をつくる努力をしなければならない．

　このたび筆者が中心となって，脳ドックのガイドライン2008，無症候性未破裂脳動脈瘤への対応を改定した（http://www.snh.or.jp/jsbd/pdf/guideline2008.pdf）．本稿ではその内容を中心に，未破裂脳動脈瘤の治療方針について現時点で得られている情報から考えうることを解説したい．また現在筆者の施設において気をつけている未破裂脳動脈瘤の治療のポイントについて示したい．

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