Impact of Surgical Revascularization on Regression of Enlarged Perivascular Spaces in Adult Moyamoya Disease

Objective Previous studies have suggested that enlarged perivascular spaces (EPVSs) are potential radiological markers of cerebral ischemia in moyamoya disease (MMD). However, serial changes in EPVSs after surgical revascularization have not yet been clarified. In the present study, we evaluated the change of EPVSs after surgical revascularization in adult patients with MMD. Methods This was a single-center study. We counted the EPVSs in the basal ganglia (BG) and centrum semiovale (CSO) in each hemisphere on T2-weighted MRI performed upon admission. EPVSs were also quantified three months and two years after combined bypass surgery in surgically treated patients and compared with the number of EPVSs before surgery. We performed multivariate logistic regression analysis to identify the clinical and radiological factors associated with the number of EPVSs. Results This study included 120 hemispheres of 65 adults with MMD. Older age (P = 0.04) and hypertension (P = 0.04) were significantly associated with a larger baseline number of EPVSs in the BG. Older age (P < 0.01), posterior cerebral artery (PCA) involvement (P < 0.01), and cerebral blood flow (CBF) impairment (P = 0.02) were significantly associated with a large number of EPVSs in the CSO. The number of EPVSs only in the CSO markedly decreased at three months and two years after surgery compared with that before surgery (P < 0.01). Conclusions The number of EPVSs in the CSO was closely associated with age, PCA involvement, and CBF impairment in adult patients with MMD, which remarkably regressed after surgical revascularization. EPVSs are reversible radiological markers reflecting impaired cerebral hemodynamics in adult patients with MMD.