# Ocular Manifestations of Multiple Sclerosis: A Retrospective, Population-Based Single-Center Study

## TL;DR

This study examines how multiple sclerosis affects vision, finding that optic neuritis is a common early sign and that eye exams can help diagnose MS early.

## Contribution

The study provides population-based data on the prevalence of specific ocular manifestations in MS patients and the role of visual evoked potentials in diagnosis.

## Key findings

- Optic neuritis was the most common afferent visual pathway issue and often the first sign of MS.
- Nystagmus and internuclear ophthalmoplegia were the most frequent efferent visual pathway issues.
- Visual evoked potentials were effective in detecting both obvious and hidden visual pathway abnormalities.

## Abstract

Background and objective

Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system by causing inflammation and damage to myelinated axons. It often impacts the visual pathways, and optic neuritis (ON) is commonly the first symptom people notice. Eye movement disorders, including internuclear ophthalmoplegia (INO) and nystagmus, may result in double vision, oscillopsia, and reading fatigue. MS is also linked to ocular inflammation, such as pars planitis and retinal periphlebitis. This study aimed to identify the most common eye-related symptoms of MS and to determine the proportion of patients with afferent and efferent visual disturbances. Additionally, the study assessed the contribution of visual evoked potentials (VEPs) in detecting visual pathway abnormalities and identified ocular findings that represented the initial clinical manifestation of MS.

Methods

This retrospective study analyzed 192 MS patients evaluated in an ophthalmology clinic. Data were obtained from structured questionnaires completed during routine visits.

Results

Among the 192 MS patients, 30 were male, and 162 were female. Most patients (54%) were between 20 and 30 years old. Ocular symptoms were reported by 120 patients, and for 81, these were the first sign of MS. Visual field (VF) defects were found in 93 patients, mostly in the afferent pathway (89), while 48 had efferent pathway defects. The most common VF defect was field narrowing. Four patients had other autoimmune diseases. Seventy-six patients had positive VEPs, which was statistically significant (p < 0.001).

Conclusions

In this study, most patients were women aged 20 to 30, showing that MS is more common in young adult women. ON was the most frequent afferent visual pathway problem, matching its known role as an early sign of MS. For efferent issues, nystagmus (12%) and INO (9%) were most common, with the sixth cranial nerve most often affected. VF narrowing was the most common defect, highlighting the need for thorough visual exams. VEPs helped detect both obvious and hidden visual pathway problems, proving useful for routine checks and early MS diagnosis. A small number of patients (2%) had other autoimmune diseases, so physicians should be on the lookout for these conditions. These results highlight the need for comprehensive eye exams, including VEP and perimetry, in MS patients to support early treatment, improve vision, and coordinate care.