Clinical outcome after 450 revascularization procedures for moyamoya disease

Object. Moyamoya disease (MMD) is a rare cerebrovascular disease mainly described in the Asian literature. To address a lack of data on clinical characteristics and long-term outcomes in the treatment of MMD in North America, the authors analyzed their experience at Stanford University Medical Center. They report on a consecutive series of patients treated for MMD and detail their demographics, clinical characteristics, and long-term surgical outcomes. Methods. Data obtained in consecutive series of 329 patients with MMD treated microsurgically by the senior author ( G. K. S.) between 1991 and 2008 were analyzed. Demographic, clinical, and surgical data were prospectively gathered and neurological outcomes assessed in postoperative follow-up using the modified Rankin Scale. Association of demographic, clinical, and surgical data with postoperative outcome was assessed by chi-square, uni- and multivariate logistic regression, and Kaplan-Meier survival analyses. Results. The authors treated a total of 233 adult patients undergoing 389 procedures (mean age 39.5 years) and 96 pediatric patients undergoing 168 procedures (mean age 10.1 years). Direct revascularization technique was used in 95.1% of adults and 76.2% of pediatric patients. In 264 patients undergoing 450 procedures ( mean follow-up 4.9 years), the surgical morbidity rate was 3.5% and the mortality rate was 0.7% per treated hemisphere. The cumulative 5-year risk of perioperative or subsequent stroke or death was 5.5%. Of the 171 patients presenting with a transient ischemic attack, 91.8% were free of transient ischemic attacks at 1 year or later. Overall, there was a significant improvement in quality of life in the cohort as measured using the modified Rankin Scale (p < 0.0001). Conclusions. Revascularization surgery in patients with MMD carries a low risk, is effective at preventing future ischemic events, and improves quality of life. Patients in whom symptomatic MMD is diagnosed should be offered revascularization surgery. (DOI: 10.3171/2009.4.JNS081649)