Optical coherence tomography in secondary progressive multiple sclerosis: cross-sectional and longitudinal...

Area of Science:

• Neuroscience
• Ophthalmology
• Radiology

Background:

• Optical coherence tomography (OCT) inner retinal metrics are recognized indicators of neurodegeneration in multiple sclerosis (MS).
• Investigating OCT measures as potential biomarkers for disease severity in secondary progressive multiple sclerosis (SPMS) is crucial for patient management.

Purpose of the Study:

• To explore the utility of OCT measures as biomarkers of disease severity in patients with SPMS.
• To correlate inner retinal thicknesses with clinical and imaging outcomes in SPMS.

Main Methods:

• Analysis of brain MRIs, clinical assessments, and OCT data from 212 participants with SPMS at baseline and 96 weeks.
• Measurement of peripapillary retinal nerve fibre layer (pRNFL) and macular ganglion cell-inner plexiform layer (GCIPL) thicknesses.
• Statistical analyses including correlations, multivariable linear regressions, and mixed-effects models to assess associations.

Main Results:

• Baseline pRNFL and GCIPL thicknesses correlated with Symbol Digit Modalities Test (SDMT) scores and deep grey matter volume.
• pRNFL and GCIPL thicknesses were associated with changes in Expanded Disability Status Scale (EDSS) score, Timed 25-Foot Walk (T25FW), and brain volume.
• Significant annualised thinning rates were observed for both pRNFL (-0.83 µm/year) and GCIPL (-0.37 µm/year).

Conclusions:

• OCT measures correlate with key clinical and imaging markers of disease severity in SPMS patients with long disease duration.
• OCT-derived retinal metrics show potential as non-invasive biomarkers for tracking neurodegeneration and disease progression in SPMS.