Baseline Hemodynamic Impairment and Revascularization Outcome in Newly Diagnosed Adult Moyamoya Disease Determined by Pseudocontinuous Arterial Spin Labeling

OBJECTIVE: The study aimed to investigate the hemodynamic features and independent predictors of neoangiogenesis after revascularization in moyamoya disease (MMD) by pseudocontinuous arterial spin labeling magnetic resonance imaging (pCASL MRI). METHODS: Thirty-nine MMD patients were categorized into infarction group, hemorrhagic group, and atypical group. All patients underwent combined bypass surgery and pCASL MRI with postlabeling delays (PLD) of 1525 ms and 2525 ms. Absolute CBFMCA (cerebral blood flow in middle cerebral artery territory), relative CBFMCA (CBFMCA 2525 ms/CBFMCA 1525 ms), and spatial coefficient of variation of MCA (CoVMCA) were analyzed. Relationships between CBFMCA and the following clinical parameters were assessed: Suzuki stage, modified Rankin scale (mRS), cerebrovascular accident lesion score, and deep medullary veins score. Potential predictors for favorable neoangiogenesis and hemodynamic changes were explored as well. RESULTS: Preoperative CBF(MCA )differed among MMD patients with variable clinical presentations, Matsushima stages, modified Rankin Scale scores, CVA scores, and deep medullary vein scores. After bypass surgery, mean CBF(MCA )increased significantly in the infarction group(P[0.027) and decreased in the hemorrhagic group (P[0.043), while spatial CoV(MCA )was observed to decline in all groups. Higher preoperative relative CBFMCA and spatial CoVMCA were independent predictors for robust neoangiogenesis after bypass. The cutoff value of 0.330 of spatial CoV(MCA )at long PLD yielded the best sensitivity at 82.1%and specificity at 81.8%. Furthermore, both preoperative relative CBF(MCA )and spatial CoVMCA showed mild positive correlations with delta mRS in MMD patients. CONCLUSIONS: pCASL-MRI with multiple PLDs could reflect preoperative hemodynamic impairment and predict the neoangiogenesis after combined bypass surgery in moyamoya patients