Moyamoya disease presenting with subarachnoid hemorrhage: Clinical features and neuroimaging of a case series

Background. Hemorrhage is a major category of the clinical symptoms of moyamoya disease (MMD). Intracerebral and intraventricular hemorrhages are the most common hemorrhages in MMD, and subarachnoid hemorrhages (SAHs) are notably rare. There have only been a few previous case reports of this imaging manifestation. In the present study, we investigated the clinical and neuroimaging features of MMD patients who presented with SAH and sought to identify the possible causes of hemorrhage. Methods. The right and left cerebral hemispheres of each patient were identified as hemorrhagic or non-hemorrhagic. Each hemisphere was assessed for Suzuki stage, and dilatation and branch extension of the anterior choroidal artery (AChA) and posterior communicating artery (P-CoM) and for the degree of transdural anastomosis and posterior circulation compensation. Next, these data were statistically analyzed for correlations with the SAH events. Results. In 34 of 349 hemorrhagic MMD patients, the first episode of hemorrhage ...