Abstract Details

Title Cerebral Hyperperfusion Syndrome Incidence following Moyamoya Revascularization Surgery: A Meta-analysis of Incidence, Meta-regression of Trends, and Cumulative Evidence

Topic Cerebrovascular Disease and Interventional Neurology

Presentation(s) P9 - Poster Session 9 (5:00 PM-6:00 PM)

Poster/Presentation
Number 4-022

Objective This meta-analysis aimed to determine the precise incidence of cerebral hyperperfusion syndrome (CHS) following revascularization surgery for moyamoya disease (MMD) across different patient populations and surgical procedures.

Background

CHS is a well-known, serious complication after MMD revascularization surgery, but a comprehensive evaluation of its incidence has been lacking.

Design/Methods A systematic review and single-arm meta-analysis was conducted using databases including PubMed, Scopus, and Web of Science up to August 2025. The analysis pooled incidence rates for CHS in adult and pediatric patients who underwent direct or combined bypass surgery. Heterogeneity was assessed using I² statistics, and publication bias was evaluated with funnel plots.

Results Among 5758 patients in 65 studies, the overall pooled incidence of CHS was 17% (95% CI: 13%-21%). Subgroup analysis revealed an incidence of 18% in adults and 11% in pediatric patients. By surgical approach, the incidence was 16% for combined surgery and 17% for direct bypass. Analysis of adverse events found incidences of 23% for hematoma, 18% for seizure, 32% for progress rate, and 59% for transient neurologic deficits. Meta-regression indicated a stable incidence over time for the overall and adult cohorts, but a potential decrease in pediatric cases. The incidence of hematoma and seizure appeared to decline, while the reported progress rate increased. Funnel plots suggested a generally low risk of publication bias for most outcomes. Cumulative analysis showed that effect estimates stabilized over time, becoming more precise after 2012.

Conclusions CHS is a common complication following revascularization for MMD, reported in approximately 17% of patients, more commonly reported in adults. Risk for individual adverse events, particularly transient neurologic deficits, is high. In spite of overall incidence being unchanged, trends show that some outcomes improve with time. These findings endorse the need to remain cautious and initiate effective management strategies for CHS.

Authors/Disclosures
Abdullah Serhan, MD PRESENTER	Dr. Serhan has nothing to disclose.
Bara M. Hammadeh	Mr. Hammadeh has nothing to disclose.
Mohammad M. Hamad	Mr. Hamad has nothing to disclose.
Talal F. Salem, MD	Dr. Salem has nothing to disclose.
Mohammed Awamleh, MD	Mr. Awamleh has nothing to disclose.
Abdullah jariri, MD	Dr. jariri has nothing to disclose.
Yakeen Asha	Miss Asha has nothing to disclose.
Ethar Hazaimeh, MD	Dr. Hazaimeh has nothing to disclose.
Omar Jbarah (Jordan University of Science and Technology)	Omar Jbarah has nothing to disclose.
Hiroki Kurita, MD, PhD	Prof. Kurita has nothing to disclose.