The Clinical and Neuroimaging Factors of Stroke Outcome of Unilateral Moyamoya Disease.

Rationale and objectives: The clinical feature and long-term prognosis of unilateral moyamoya disease (MMD) have not been fully described and studied. The study aimed to investigate independent risk factors for stroke in unilateral MMD patients during a long-term follow-up.

Materials and methods: A total of 393 unilateral MMD patients (median age, 40 years) were assessed at baseline and followed for an average time of 68.9 months. Ischemic and hemorrhagic stroke incidence rates were determined. Multiple demographic, clinical and neuroimaging factors at baseline were considered as potential predictors of stroke during the follow-up period. Hazard ratios (HR) and corresponding 95% confidence interval (CI) for stroke were calculated by univariable and multivariable Cox proportional hazards models. Cumulative risk of stroke was estimated by the Kaplan-Meier product-limit method.

Results: During the follow-up period, 43 patients experienced stroke events (10.9%). 5 children experienced stroke events (5/46, 10.9%) and 38 adults experienced stroke events (38/347, 11.0%) (P>0.05). 21 patients with encephaloduroarteriosynangiosis (EDAS) experienced stroke events (21/254, 8.3%) and 22 patients with conservative treatment experienced stroke events (22/139, 15.8%) (P<0.05). After adjustment for clinical characteristics, multivariable analysis showed that involvement of posterior cerebral artery (HR, 2.199; 95% CI, 1.100-4.398), decreased cerebral blood flow (CBF) (HR, 2.292; 95% CI, 1.182-4.446) and concentric enhancement of the arterial wall (HR, 3.093; 95% CI, 1.617-5.915) were significantly associated with stroke, and EDAS (HR, 0.385; 95% CI, 0.203-0.730) and compensatory blood supply by anterior communicating artery (HR, 0.413; 95% CI, 0.206-0.830) were protective factors for stroke.

Conclusion: Involvement of posterior cerebral artery, decreased CBF, concentric enhancement of the arterial wall, EDAS and compensatory blood supply by anterior communicating artery may help stratify the risk of stroke and improve therapeutic decisions in unilateral MMD. Unilateral MMD could benefit from EDAS and have a lower risk of future stroke.