Evaluation of the retinal nerve fiber layer thickness and its relation to visual evoked potentials in multiple sclerosis
Abstract
Purpose
To evaluate the retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT) in Lithuanian patients with multiple sclerosis (MS) and to assess the relationship between RNFL thickness and visual evoked potentials (VEP).
Methods
From 2013 till 2014 a prospective study involving 71 patients with multiple sclerosis was conducted in Vilnius University Hospital Santariškių Clinic Center of Neuroscience and Eye Diseases. The epidemiological, clinical, laboratory and instrumental data was assessed: gender, age, oligoclonal bands, IgG index in cerebrospinal fluid (CRF), visual evoked potentials (VEP), OCT. RNFL and papilomacular bundel (PMB) thicknesses were performed with SD-OCT.
Results
The distribution of gender for patients with MS was as follows: men n = 22 (31%), women n = 49 (69%); average age −40.7 ± 10.7 years. OCT results were as follows: RNFL average thickness: right eye 85.5 ± 15.6 μm, left eye 86.3 ± 13.2 μm. According to the t-test: the upper nasal (NS) segment averages of right and left eyes differed statistically significant −6.6 ± 14.7 μm (p < 0.05). There was significant negative correlation between VEP P100 latency and RNFL thickness of the right eye TI segment (r = −0.57; p = 0.01) and the left eye PMB segment (r = −0.52; p = 0.02). The most damaged segment was the temporal (T) one: right eye 84.5% (n = 60), left eye −90.1% (n = 64). RNFL of both eyes revealed statistically significant mean differences with the IgG index.
Conclusions
The most vulnerable segment of the retina is the temporal. If VEP gets prolonged thinning of RNFL is also observed. The CSF index is increased by immunologically more active multiple sclerosis. We think that more active form of MS may be associated with retinal segments violation. Hence we may conclude that RNFL thinning could be related with irreversible progression of the disease.
