Chronic Migraine Is Associated With Region-Specific High-Grade Enlarged Perivascular Spaces: Retrospective Matched Case-Control Study

Background and Purpose Enlarged perivascular spaces (EPVS) observed on magnetic resonance imaging (MRI) reflect impaired glymphatic system (GS) function; however, their association with chronic migraine remains unclear.This study aimed to investigate whether chronic migraine is associated with a high burden of region-specific high-grade EPVS.Methods This retrospective case-control study included 44 patients with chronic migraine, 44 age-and sex-matched patients with episodic migraine, and 39 matched healthy controls.Brain MRI scans were assessed for EPVS in the centrum semiovale (CS), basal ganglia, and midbrain (MB) using a validated visual rating scale.High-grade EPVS was defined according to regionspecific criteria.Logistic regression analyses were performed to evaluate the association between chronic migraine and high-grade EPVS, adjusting for age, sex, hypertension, alcohol consumption, and insomnia. ResultsThe prevalence of high-grade EPVS in the CS and MB differed significantly among the chronic migraine, episodic migraine, and control groups.Post-hoc analysis revealed a significantly higher prevalence in the chronic migraine group compared to controls in both regions, and compared to the episodic migraine group in the CS.Chronic migraine was independently associated with high-grade EPVS in the CS (adjusted odds ratio [OR]=9.345,p<0.001) and MB (adjusted OR=4.026, p=0.007).Conclusions Chronic migraine is associated with an increased prevalence of high-grade EPVS in specific brain regions, suggesting an underlying GS dysfunction.Thus, EPVS is a potential imaging biomarker of chronic migraine.