Abstract
BACKGROUND: Enlarged perivascular spaces (EPVSs) are associated with a number of cerebrovascular diseases and have been observed in patients with moyamoya disease (MMD); however, their characteristics in pediatric patients with MMD have not been characterized. We aimed to identify the characteristics and risk factors of EPVS in pediatric MMD and to determine if they differ from those of adult moyamoya. Especially, we identified the systemic immune-inflammatory markers reflecting systemic inflammation and immune status and the unique hyperintense medullary streaks observable on fluid-attenuated inversion recovery imaging (HMSFs) in pediatric MMD. METHODS: The data of 72 participants, including 36 pediatric patients of MMD and 36 age/sex-matched children without cerebrovascular diseases were collected. The burden of EPVS in the centrum semiovale per hemisphere was calculated and categorized into five grades (0-4) in each hemisphere. The clinical and radiological features were analyzed between MMD and controls and between the low- (EPVS grade =0-3) and high-EPVS grade group (EPVS grade =4). We evaluated EPVS in relation to risk factors that emerged from the aforementioned statistical analysis (P<0.05). These factors encompassed MMD, hypertension, white-matter lesions, systemic immune-inflammatory marker platelet-to-lymphocyte ratio (PLR), and HMSFs. RESULTS: EPVS counts and grades (P<0.0001), PLR (P<0.05), and HMSF counts (P<0.01) were significantly higher in pediatric MMD and the high-EPVS grade group. In univariate analyses, EPVSs were found to be significantly related to MMD (P<0.001), white-matter lesions (P<0.001), PLR (P=0.010), and HMSFs (P<0.001). In multivariate analyses, EPVSs were associated with MMD (P<0.001) and HMSFs (P=0.01). In the pediatric MMD group, EPVS grades were associated with PLR (P=0.04). CONCLUSIONS: Patients with pediatric MMD exhibited increased EPVS number, HMSF counts, and PLR as compared to control participants. MMD is a risk factor for EPVSs.