This study aimed to assess the correlation between RNFL thickness and disease severity in MS patients in absence of previous optic neuritis (ON).

This retrospective analysis was performed on 81 multiple sclerosis patients (71.6% female, mean age 35 years) with no prior history of optic neuritis. The thickness of the RNFL was assessed using OCT and compared with normal values. Clinical factors, such as Expanded Disability Status Scale (EDSS) scores and disease duration, were examined for relationships with retinal nerve fiber layer (RNFL) thickness.

The average RNFL thickness in MS patients (87.7 ± 13.0 µm) was substantially lower than that of healthy controls (110.01 ± 7.39 µm, p < 0.001), with the most pronounced thinning occurring in the nasal quadrant (−26.98%). An negative connection was identified between RNFL thickness and EDSS scores (r = −0.34, p = 0.034), with patients with substantial disability demonstrating reduced RNFL thickness (74.6 ± 8.1 µm) relative to those with light disability (89.4 ± 12.8 µm). No notable correlation was detected with disease duration (p = 0.838). Patients receiving high-efficacy disease-modifying treatments (DMTs) had enhanced preservation of retinal nerve fiber layer (RNFL) (p = 0.04).