Predictors for Revascularization Patterns After Bypass Procedures for Moyamoya Disease in Adults

Area of Science:

• Neurosurgery
• Neurology
• Vascular Surgery

Background:

• Combined revascularization is effective for moyamoya disease (MMD), reducing ischemic events.
• Predictors for the degree of revascularization in MMD patients are not well-defined.
• Identifying patient-specific factors is crucial for optimizing surgical outcomes.

Purpose of the Study:

• To identify preoperative factors associated with postoperative revascularization patterns in adult MMD patients.
• To determine predictors of successful revascularization after combined procedures.
• To enhance patient selection for direct bypass surgery in MMD.

Main Methods:

• Analysis of clinical and radiographic data from 33 adult MMD patients undergoing combined revascularization (2020-2025).
• Assessment of preoperative factors including internal carotid artery (ICA) terminus flow, collateral flow, MMD severity (Berlin grade), age, sex, and cerebrovascular reserve (CVR).
• Firth's penalized logistic regression used to identify predictors of postoperative revascularization (Matsushima grade - MG).

Main Results:

• Absence of anterograde ICA flow was an independent predictor of achieving Matsushima grade A (OR 46, p=0.001).
• Patients with Matsushima grade A showed improved cerebral perfusion (p=0.008).
• No significant association was found between revascularization grade and modified Rankin Scale (mRS) improvement (p=0.739).

Conclusions:

• Absence of preoperative anterograde ICA flow independently predicts robust postoperative revascularization in adult MMD.
• Preoperative ICA patency assessment may serve as a biomarker for patient selection for direct bypass.
• This finding can guide surgical planning to maximize benefits for MMD patients.