Analysis of Visual Acuity, Contrast Sensitivity and Color Perception in Multiple Sclerosis Patients

¹Celia Oreja-Guevara, ¹Johnny Quezada-Sánchez, ¹Martínez-Pérez E, ¹Judit Díaz-Díaz, ¹Irene Gómez-Estévez, ¹Elda Alba Suárez

¹Hospital Clínico San Carlos, Madrid, Spain

Background:

Optic neuritis is a very frequent manifestation in the course of the disease and can lead to changes in visual function. The main objective of this study was to analyze low contrast visual acuity (VA), contrast sensitivity (CS) and color perception in multiple sclerosis patients with and without optic neuritis.

Material(s) and Method(s):

MS patients with more than six months of follow-up and clinically stable in the last six months were analyzed. We performed a complete ophtalmologic study. Low contrast VA was assessed with the ETDRS Bailey-Lovie test at 2.50% and 1.25%, SC with the Pelli-Robson test and chromatic perception with the Ishihara test and the Farnsworth-Munsell D28 test. We compared patients with optic neuritis and those without optic neuritis.

Result(s):

Of the 50 eyes that were evaluated, 16 had some past optic neuritis and 34 had no previous optic neuritis. There were 18 females with a mean age of 42.65 and 7 males with a mean age of 44.69. Patients who had past optic neuritis showed a slight decrease in low contrast VA (greater reduction in the 1.25% test than in the 2.50% test) both monocularly and binocularly, with respect to those who have never had an optic neuritis. In the contrast sensitivity test, reduced values were also observed in those who had previous optic neuritis. In the chromatic preception tests it was observed that the results obtained in the Ishihara test were normal with a reading of 17 lamellae or more, while in the Farnsworth Munsell D28 test only 12 patients were normal trichromats in both eyes, 2 patients clearly showed color defects in the blue-yellow axis (tritan) in both eyes, 2 patients showed an undefined pattern in both eyes and the rest of the patients presented different patterns in each eye.

Conclusion(s):

To discriminate chromatic alterations in patients with MS, it seems that the Farnsworth Munsell D28 test is more sensitive than the Ishihara test in all patients who were evaluated. This leads us to believe that MS may affect color perception more slowly resulting in clearly defined patterns, such as blue-yellow axis defects, in the long term. Patients with optic neuritis have worse low-contrast VA and worse contrast sensitivity.