MRI Evaluation of Glymphatic Dysfunction in Cerebral Small Vessel Disease: Hypertensive vs. Normotensive Patients.

The glymphatic system (GS) serves as the brain's waste clearance pathway, with dysfunction implicated in neurodegenerative disorders-particularly cerebral small vessel disease (CSVD). As hypertension is a modifiable risk factor strongly linked to CSVD progression, we compared magnetic resonance imaging-derived (MRI-derived) GS metrics between hypertensive and normotensive CSVD patients. So, in this study, we retrospectively analyzed 72 clinically diagnosed CSVD patients (37 hypertensive [CSVD_HT+], 35 normotensive [CSVD_HT-]), and 40 age-matched healthy controls (HCs). Key MRI-derived GS indices included: perivascular space volume fraction (PVS-VF), diffusivity along perivascular spaces (ALPS index), free water in white matter (FW-WM), and choroid plexus volume (Chp). CSVD patients exhibited abnormal MRI-derived indices, Compared to CSVD_HT- individuals, CSVD_HT+ were characterized by lower ALPS index, higher FW-WM and hypertrophy of Chp. Random systolic blood pressure (SBP) negatively correlated with ALPS index (r = -0.220, p = 0.055), while positively correlating with FW-WM (r = 0.460, p < 0.001), and Chp volume (r = 0.310, p = 0.006). Cognitive assessments revealed associations between ALPS index and memory scores (r = 0.280, p = 0.020). These findings suggest that elevated SBP exacerbates GS impairment in CSVD, underscoring the critical role of blood pressure management. Longitudinal studies are needed to confirm these observations.