Hemorrhage in Adult Moyamoya Disease With Intracranial Aneurysms: A Long-Term Observational Study on the Roles of Moyamoya Vessels and Admission Glasgow Coma Scales

BACKGROUND: Moyamoya disease (MMD) is a chronic progressive cerebrovascular disease characterized by bilateral steno-occlusive changes at the terminal internal carotid arteries. Fragile vascular wall alterations combined with hemodynamic stress may facilitate intracranial aneurysm formation. This study aimed to identify risk factors of intracranial hemorrhage in MMD patients with associated aneurysms. METHODS: Between March 2014 and October 2021, a consecutive cohort of 69 patients who were diagnosed with MMD associated with aneurysms was enrolled in this retrospective single-center study. Treatments, including conservation, endovascular intervention, surgical clipping, and revascularization, were conducted in patients based on individual status and clinical experience. Hemorrhage was noticed by annual clinical visit or telephone and confirmed by computed tomography. RESULTS: This cohort of MMD with IA underwent a median follow-up of 76.2 months. During this period, 17 patients experienced hemorrhage while 52 maintained hemorrhagic-free survival. Logistic regression showed that ipsilateral moyamoya vessels with aneurysms (P=0.018) and low admission GCS (P<0.001) were independent predictors of hemorrhage. Cox regression analysis also confirmed both factors (P=0.003; <0.001) had a statistical association with reduced hemorrhage-free survival. No significant differences between the nonhemorrhagic and hemorrhagic groups were observed in sex, age, previous hemorrhage, or impaired perfusion on computed tomography perfusion between the 2 groups. CONCLUSIONS: Hemorrhage constituted a clinically significant incident in MMD with aneurysm, characterized by relatively high frequency and catastrophic neurological consequences. Ipsilateral moyamoya vessels harboring aneurysms and low admission GCS were independent factors for hemorrhage following initial intervention. Both factors also correlated with shorter hemorrhage-free survival.