Impaired glymphatic system function in relapsing-remitting multiple Sclerosis: Insights from diffusion tensor imaging...

Area of Science:

• Neuroimaging
• Neurology
• Radiology

Background:

• Glymphatic dysfunction, characterized by enlarged perivascular spaces, cognitive impairment, and inflammation, is linked to relapsing-remitting multiple sclerosis (RRMS).
• Diffusion tensor image analysis along the perivascular space (DTI-ALPS) is a novel technique to assess glymphatic function.

Purpose of the Study:

• To evaluate glymphatic function in RRMS patients using DTI-ALPS.
• To investigate the association between DTI-ALPS index, diffusion tensor imaging (DTI) metrics, and clinical variables in RRMS.

Main Methods:

• 39 RRMS patients and 34 healthy controls (HC) underwent DTI-ALPS analysis.
• Regions of interest were placed in fiber areas, and lesion masks were used to exclude affected areas from diffusion coefficient calculations.
• DTI metrics (FA, MD, AD, RD) and clinical data (disease duration, disability score) were analyzed alongside the DTI-ALPS index.

Main Results:

• RRMS patients exhibited a significantly lower DTI-ALPS index compared to HC, indicating altered water diffusivity along perivascular spaces.
• The DTI-ALPS index negatively correlated with clinical disability and disease duration in RRMS patients.
• RRMS patients showed decreased fractional anisotropy (FA) and increased mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD).

Conclusions:

• Altered DTI-ALPS index in RRMS suggests impaired glymphatic function.
• Changes in DTI-ALPS index are associated with microstructural damage and disease progression in RRMS.
• DTI-ALPS may serve as a potential imaging biomarker for glymphatic dysfunction in multiple sclerosis.