OPTICAL COHERENCE TOMOGRAPHY (OCT) IN ASSESSING RETINAL NEURODEGENERATION AND DISEASE PROGRESSION IN MULTIPLE SCLEROSIS

Abstract

Optical coherence tomography (OCT), anterior and posterior segment structures can be visualized with unprecedented high resolution in cross-sectional images. With the non-invasive nature of OCT, in particular the potential for tracking disease progression and visual outcome, there has been increasing interest in studying its utility for retinal change monitoring in multiple sclerosis (MS). Objective: The aim of this study is to investigate OCT sensitivity in predicting visual and disease progression in 100 MS patients over a period of 9 months by looking at if (or not) that parameters independently predict clinical outcome. Methods: A prospective cohort study was conducted at Lady Reading Hospital, Peshawar where patients were followed at baseline and 3, 6 and 9 months. OCT parameters assessed were: Peripapillary RNFL Thickness, Macular GCIPL Thickness, Temporal RNFL Thickness, Macular Volume and presence of Hyperreflective Foci. Visual acuity (logMAR) and Expanded Disability Status Scale (EDSS) measurements were also noted. Correlations between OCT findings and clinical parameters were analysed. Results: A significant temporal thinning in Peripapillary RNFL, Macular GCIPL and Temporal RNFL was noted over time, and retinal thinning strongly correlated with visual acuity changes. Macular volume was decreased indicating structural effects of MS on the retina. Hyperreflective foci, observed in many patients, were indicative of retinal injury. Furthermore, OCT parameters were correlated with EDSS scores thus demonstrating that OCT could constitute a predictive tool of disease severity and activity. Conclusion: OCT is a reliable, non-invasive strategy to follow retinal changes in MS. Retinal layer thinning and macular volume changes represent important parameters for the follow-up of disease evolution as well as for visual outcomes, allowing an early detection of MS-related retinal injury. This study demonstrates the potential utility of OCT in shaping and optimizing individual treatment and patient monitoring for MS, which should be further explored in larger cohorts with broader MS phenotypes.

Keywords: Optical Coherence Tomography (OCT), Retinal changes, Multiple sclerosis (MS), Disease evolution, Visual outcomes.