もやもや病に対する直接バイパス術の長期効果と統合画像を利用した治療戦略およびMRI上のMicrobleedsの意義(<特集>もやもや病-治療戦略と長期予後) Long-term Results of Direct Bypass and Application of Co-registrated Imaging to the Treatment of Moyamoya Disease(<Topics>Moyamoya Disease: Treatment Strategies and Long-term Prognosis)

A retrospective analysis of 70 patients with moyamoya disease (MMD), 56 of whom received direct bypass, suggested direct bypass did not significantly reduce the occurrence of cerebral hemorrhage but did reduce ischemic stroke. A prospective analysis of 50 patients with 3-tesla magnetic resonance (MR) imaging indicated that the presence of multiple microbleeds is an independent risk factor of subsequent cerebral hemorrhage in MMD. An analysis with co-registrated imaging between MR images and cerebral blood flow (CBF) images suggested an inverted correlation between the decrease of regional CBF before surgery and the postoperative increase of CBF. Co-registrated imaging also preoperatively identified a recipient artery at the site with decreased CBF in direct bypass surgery. Results of 15 cases with this "target bypass" method appeared to be feasible.