Background: Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disorder. Patients diagnosed asymptomatic MMD should have no prior ischemic or hemorrhagic episode and no history of neurologic diseases. The incidence of asymptomatic MMD has turned out to be higher than previously thought due to better diagnosis with the increasing availability of magnetic resonance imaging or magnetic resonance angiography technology. However, the clinical symptoms of asymptomatic MMDs are still obscure.
Clinical Case: This report presents an asymptomatic MMD patient, who was a previously healthy 42-year-old-woman. The patient suffered from burst coma and started vomiting 3 hours before hospitalization. The patient died of the rupture of hemorrhage located on the right temporal lobe near the cortex. Autopsy revealed that the vascular networks were increased at the right postcentral gyrus and on the surface of the occipital lobe.
Conclusions: As a small number of asymptomatic MMD patients have clinical symptoms, we must be aware of the possibility of MMD. The clinical symptoms of transient ischemic attack, ischemic stroke, or/and intracranial bleeding maybe the manifestation of this disease. Early recognition, accurate diagnosis and prompt treatment are vital to the survival of the patients with asymptomatic MMD.