Cerebral revascularization for moyamoya disease in adults

The cause of and best treatment for adult moyamoya disease remain uncertain. These patients present either with ischemic or hemorrhagic symptoms, and without treatment, they have a high risk of future events. Direct STA-MCA bypass does seem to improve CBF and hemodynamics and also seems to reduce the risk of rebleeding, although it does not eliminate the risk. It is significantly more effective in prevention of ischemic episodes. Direct bypass does seem superior to indirect revascularization in adult patients, and a combined procedure may be performed when possible. Direct treatment of distal aneurysms is usually not indicated, because the aneurysms are often not visible on angiography. After revascularization, a decrease in the perfusion pressure in the basal moyamoya vessels is thought to reduce the hemodynamic stress that leads to vessel rupture. Because significant controversy surrounding the efficacy of therapy exists, a prospective controlled trial is necessary to truly determine the appropriate treatment.