Effectiveness of Superficial Temporal Artery–Middle Cerebral Artery Anastomosis in Adult Moyamoya Disease

Abstract

Background and Purpose —The efficacy of superficial temporal artery–middle cerebral artery (STA-MCA) anastomosis in adult moyamoya disease was evaluated by clinicopathophysiological studies. Methods —Fifteen patients with cerebral ischemic attacks (ischemia group) and 15 patients with intracranial hemorrhages (hemorrhage group) were investigated. Clinicoangiographic features and regional cerebral blood flow (rCBF) of the MCA territory were preoperatively and postoperatively investigated, and cortical arterial pressure (CAP) and anastomotic blood flow (AF) were intraoperatively measured. Results —In the ischemia group, the preoperative rCBF of 38.4 mL/100 g per minute was significantly increased to 42.1 mL/100 g per minute with a diminution of angiographic moyamoya vessels in 67% of patients after surgery. The mean CAP and AF were 25.6 mm Hg and 34.7 mL/min, respectively. Proximal and distal cerebral vascular resistance (PCVR=[Mean Systemic Arterial Blood Pressure−Mean CAP]/rCBF and DCVR=[Mean CAP/rCBF]) were 1.78 and 0.68, respectively. One patient died perioperatively as a result of intracerebral hemorrhage. During follow-up (mean, 67 months), 12 of 14 patients recovered without neurological deficits, 1 was moderately disabled because of the initial insult, and another patient experienced an intracerebral hemorrhage but recovered fully. In the hemorrhage group, the preoperative rCBF of 38.0 mL/100 g per minute was significantly increased to 42.7 mL/100 g per minute with a diminution of moyamoya vessels in 60% after surgery. The mean CAP and AF were 29.1 mm Hg and 24.1 mL/min, respectively. PCVR and DCVR were 1.72 and 0.77, respectively. One patient became hemiparetic because of perioperative intracerebral hemorrhage. During follow-up (mean, 94 months), 3 patients had fatal intracranial hemorrhages, 10 had good recoveries, and 2 had moderate disabilities. Conclusions —This study revealed a high PCVR and a very low DCVR in both the ischemia and hemorrhage groups of patients. STA-MCA anastomosis partially normalized cerebral circulation and decreased moyamoya vessels but did not completely prevent rebleeding.