“…Although no completed randomized clinical trials have addressed the benefit of surgical revascularization, the dismal prognosis of moyamoya disease [2][3][4]7,8,21,23,31,33,[41][42][43] and a large number of case series demonstrating an improved outcome in surgically treated patients have provided evidence in support of revascularization procedures in a select group of patients. 4,[7][8][9][10][11]16,17,25,29,30,32,34,40,43 Currently, the Ministry of Health and Welfare of Japan reports that bypass surgery is indicated when there are 1) repeated clinical symptoms due to apparent cerebral ischemia and (2) decreased regional cerebral blood flow, vascular response, and perfusion reserve.…”