Retinal Nerve Fiber Layer Thickness in Multiple Sclerosis

Purpose: To evaluate retinal nerve fiber layer (RNFL) thickness measured by spectral optical coherence tomography (OCT) in multiple sclerosis (MS) patients. Material and Method: Twenty six patients followed up at the neurology clinic with the diagnosis of MS according to the McDonald criteria were included in our study. Three groups were formed: group 1-MS patients with a history of optic neuritis (N: 12); group 2 - S patients without history of optic neuritis (N: 14); and group 3 (control group)-age-and sex-matched healthy individuals (N: 15). Results: The mean age was 34.07 +/- 4.49 years for the patients and 33.06 +/- 5.73 years for the control group. Considering the group with optic neuritis, 10 out of 12 patients were affected unilaterally and the remaining 2 patients were affected bilaterally. The mean RNFL thickness was 84.78 +/-.68 mu in 14 eyes and 105.10 +/- 9.17 mu in the other 10 eyes of group 1, 98.35 +/- 2.57 mu in 28 eyes of group 2, and 124.16 +/- 10.52 mu in 30 eyes of the control group. The average RNFL thickness in the affected eyes of MS patients was significantly lower than that in the unaffected eyes of MS patients and in the control group (p<0.01). Finally, sectoral analysis showed that RNFL thickness became thinnest in the temporal quadrant. Discussion: RNFL thickness decreases in MS patients especially with a history of optic neuritis. In consequence, due to its reproducibility, RNFL thickness measurement with OCT may be a useful method for determining clinically occult neurodegeneration, monitoring the treatment and following up the disease.