Moyamoya disease is a rare pathological disorder characterized by progressive intracranial artery stenosis and collateral vessel formation. Posterior cerebral artery involvement is rare with a predilection towards infarction. Herein we present a case of a young female with moyamoya disease treated with bilateral encephalomyosynangiosis which subsequently progressed to posterior cerebral artery involvement, requiring encephalomyosynangiosis to prevent further infarction.