Postoperative seizure, stroke, hemorrhage, and cerebral hyperperfusion syndrome rates in adult patients with moyamoya disease undergoing revascularization: a systematic review and proportional meta-analysis.

To compare the postoperative incidence rate of seizure, stroke, hemorrhage, and cerebral hyperperfusion syndrome (CHP) in patients undergoing revascularization for Moyamoya disease (MMD) across direct, indirect, or combined revascularization approaches. MMD is a rare, progressive cerebrovascular disorder characterized by critical stenosis of the carotid terminus leading to chronic hypoperfusion and risk for cerebral ischemia. Revascularization in MMD may lead to a risk of perioperative seizures; however, this has not been rigorously studied. PubMed, Medline, Embase, Scopus, and Web of Science were systematically searched according to the PRISMA guidelines for studies describing postoperative seizure incidence in adult moyamoya patients. The search strategy was predefined in the authors' PROSPERO protocol (CRD42024510239). The systematic review identified 31 case series describing 3,788 Moyamoya patients, including 1598 (42.19%) male and 2190 (57.81%) female. The pooled mean age was 41.30 (95% CI: 39.66-42.94) years, and the pooled mean follow-up was 31.0 (95% CI: 20.0-42.0) months. The postoperative seizure incidence was found to be 3.99% (95% CI = 1.71-7.15) in the direct, 3.75% (95% CI = 1.88-6.23) in the indirect, and 4.59% (95% CI = 2.84-6.75) in the combined approaches. The postoperative CHP incidence was 7.20% (95% CI = 1.85% - 15.67%) in the direct, and 17.39% (95% CI = 10.51% - 25.56%) in the combined approaches. The postoperative stroke incidence was 8.30% (95% CI = 3.92% - 14.13%) in the direct, 5.73% (95% CI = 3.60% - 8.33%) in the indirect, and 2.57% (95% CI = 0.89% - 5.09%) in the combined approaches, furthermore the postoperative hemorrhage incidence was 1.57% (95% CI = 0.40% - 3.48%) in the direct, 4.26% (95% CI = 0.74% - 10.48%) in the indirect and 3.70% (95% CI = 1.87% - 6.11%) in the combined approaches. There were no statistically significant differences in post-operative seizure incidence, stroke, hemorrhage, and cerebral hyperperfusion syndrome rate across the three surgical approaches.