Diagnosis and treatment of adult Moyamoya disease

ABSTRACT

Moyamoya disease (MMD) refers to a chronic progressive steno-occlusive disease at the distal portion of the internal carotid artery with abnormal collateral vessel formation of unknown etiology. The definite diagnosis of MMD requires cerebral angiography or magnetic resonance angiography and/or magnetic resonance imaging after excluding other underlying diseases, particularly in adult patients. The treatment aims to improve regional cerebral blood flow to prevent cerebral ischemic events and alleviate hemodynamic instability that can provoke cerebral hemorrhage. Although various surgical revascularization methods have been introduced, combined revascularization surgery including direct revascularization is preferred over indirect revascularization only in adult MMD patients. Several recent studies have shown that surgical treatment has better outcomes and prognosis for symptomatic hemodynamically unstable MMD patients with both ischemic and hemorrhagic presentations. For asymptomatic patients, follow up with appropriate imaging is recommended. Surgery should be considered when new symptoms emerge with hemodynamic aggravation.