[Effect of treatment in loss of retinal nerve fibre layer in multiple sclerosis patients]

To evaluate the effect of pathogenic treatments in the reduction of the retinal nerve fibre layer (RNFL) in patients with Multiple Sclerosis (MS) by means of ocular imaging technologies.

A total 155 eyes of 79 patients with MS were enrolled in this study. All patients underwent a complete ophthalmic examination including best corrected visual acuity using Snellen chart, colour vision using Ishihara pseudoisochromatic plates, visual field examination, optical coherence tomography (OCT), scanning laser polarimetry (GDx) and visual evoked potentials. The patients were re-evaluated after a one year period and changes were assessed in order to detect differences between treatments using the Anova statistical test. The patients were divided into four groups: 1) Patients without treatment, 2) Patients treated with interferon beta-1a, 3) Subjects who received interferon beta-1b, 4) Patients treated using glatiramer acetate.

There were no statistically significant differences between patients with or without treatment and between the four groups (P>0.05, t test), but functional and structural parameters showed greater loss in RNFL thickness in non-treated patients. Temporal quadrant RNFL thickness measured by OCT was the parameter with the highest variation (reduction of 4.97μm in patients without treatment vs 1.08μm in treated patients).

MS pathogenic treatment may be a protective factor in the RNFL loss that is associated to the disease progression. More studies are needed.