Asymptomatic moyamoya disease subsequently manifesting as transient ischemic attack, intracerebral hemorrhage, and subarachnoid hemorrhage in a short period: case report.

A 59-year-old man, who had incidentally been found to have asymptomatic moyamoya disease 4 months previously, suffered transient ischemic attack (TIA) in the left extremities. Three weeks later, he again suffered TIA, and neuroimaging examination revealed fresh subarachnoid hemorrhage in the interhemispheric cistern as well as an asymptomatic thalamic hemorrhage in the contralateral hemisphere, which was not evident at the first onset of TIA. Digital subtraction angiography confirmed the diagnosis of moyamoya disease, and single-photon emission computed tomography demonstrated significant hemodynamic compromise in the right hemisphere. He underwent superficial temporal artery-middle cerebral artery anastomosis with indirect pial synangiosis without complication one month later. The TIA completely disappeared after surgery, and no further cerebrovascular event occurred during the follow-up period of 2 years. Asymptomatic moyamoya disease may manifest with a dynamic course, so careful follow up is necessary. Simultaneous manifestation of ischemic attack, subarachnoid hemorrhage, and intracerebral hemorrhage in a short period in the present case may indicate the underlying mechanism of the cerebrovascular events in this rare entity.