Direct and indirect revascularization for moyamoya disease surgical techniques and peri-operative complications

We have performed surgical treatment for Moyamoya disease using the superficial temporal artery to middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-arterio-myo-synangiosis (EDAMS). In this paper, the surgical technique of combined revascularization for Moyamoya disease as well as peri-operative complications are discussed. Craniotomy and dural opening were extensively carried out to expose the brain surface as widely as possible. Dissection of the STA, which is the most powerful resource of direct revascularization, should be carefully carried out using a surgical microscope. The temporal muscle and middle meningeal artery, which have the most potential as sources of indirect revascularization, must be preserved. STA-MCA anastomosis to the frontal branch of the middle cerebral artery is indispensable for improving cerebral circulation of the frontal lobe. A small arachnoid membrane opening and water-tight closure are also important to avoid post-operative subdural and subcutaneous fluid collection. Ischemic events disappeared immediately after surgery in most cases. However, in several cases, transient ischemic attacks recurred for several months after the surgery. Chronic subdural hematoma was seen in two cases.