Long-Term Follow-up Study after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis plus Encephalomyosynangiosis for Moyamoya Disease

ABSTRACT

During the period from March 1990, through September 1993, 11 patients with moyamoya disease underwent superficial temporal artery(STA)-to-middle cerebral artery(MCA) anastomosis and encephalomyosynangiosis(EMS) bilaterally. The mean follow-up period was 30.6 months(range 17 to 42 months). The most frequent computed tomographic findings were intraventricular hemorrhage in adult patients and cortical infarction in pediatric patients. In all of the patients, confirmatory diagnosis could be made by angiography, and all had typical angiographic finding of moyamoya disease. According to angiographic classification by Suzuki, the most frequent phase was stage three. A modified continuous suture technique was used during anastomosis. The advantages of this microvascular suture technique are saving time for the surgical procedure, lessening bleeding from the anastomotic site and the ease and safety with which anastomosis can be achieved in the deep cranial cavity. Postoperatively, follow-up angiography was taken between 1 year and 2 years after operation. The angiography revascularization rate was 100%, excellent in 6, and good in 5. The typical postoperative angiography findings are as follows 1) reduction of moyamoya vessels, 2) normalization or improvement of abnormal posterior circulation, 3) visualization of MCA territory through MCA-STA bypass, and 4) dilatation of STA. There were no major complication in patients with surgery, and no poor outcomes. These results indicate that the STA-MCA anastomosis and EMS in moyamoya disease can normalize cerebral circulation and reduce repeat ischemic attack and repeated bleeding.