Moyamoya Across the Lifespan: Current Neurologic Care and Future Directions.

Abstract

Moyamoya arteriopathy is an important cause of stroke across the lifespan, with high rates of incident and recurrent stroke in affected individuals. Although it affects adults and children globally, moyamoya is more prevalent in East Asian countries, particularly Japan and Korea. The R4810K variant of the RNF213 gene, most common in Asian populations, is associated with severe, early onset, multisystem vasculopathy. Neuroimaging is critical for moyamoya diagnosis and treatment planning, with conventional imaging, catheter angiography, perfusion imaging, and cerebrovascular reactivity assessment all having a place within moyamoya care. Medical management of moyamoya entails reducing the competing risks of ischemic and hemorrhagic stroke as well as managing coexisting conditions, such as headache, epilepsy, and neuropsychological sequelae. Antiplatelet therapy is commonly prescribed to prevent thromboembolic stroke, although data supporting this practice are limited and practice patterns vary globally. Promoting cerebral oxygen and nutrient delivery with sufficient fluid intake, maintaining adequate blood pressure, and avoiding anemia and hypoglycemia aid in stroke prevention in moyamoya. Definitive treatment of moyamoya is predicated on surgical revascularization, which aims to augment perfusion to at-risk brain tissue and decrease the risk of hemorrhage from fragile moyamoya collaterals. Although surgery is highly effective in appropriately selected patients, perioperative ischemic events occur following 4%-18% of cases. Perioperative medical management aims to mitigate this risk by optimizing brain oxygen delivery through adequate cerebral perfusion and blood oxygenation, pain/nausea control, minimizing metabolic demand, and preventing thrombosis. Long-term neuroimaging surveillance, evaluation of the neuropsychological effect of moyamoya, and screening for and management of headache and epilepsy resulting from moyamoya are important aspects of the chronic care of all patients with moyamoya. In this review, we summarize key aspects of neurologic evaluation and management for moyamoya across the lifespan, highlight key differences between adult and pediatric moyamoya, and discuss ongoing research efforts that aim to improve care of children and adults with moyamoya.