To conduct an objective and subjective assessment of the afferent visual pathway (AVP) in multiple sclerosis (MS) patients in order to find a more sensitive parameter that demonstrate its damage.

The AVP is frequently affected in MS and visual quality of life (VQL) is commonly compromised. High contrast visual acuity (HCVA) and visual field (VF) exam are performed in clinical practice to assess visual impairment. However, this tests may be normal in a high percentage of patients with visual complaints. Therefore, this evaluation methodology has a low sensitivity to detect AVP impairment. 

A prospective cohort study was conducted. Neuro-ophthalmological assessment included: HCVA, color vision, LCLA, VF exam, VQL questionnaire using the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25I) and Optical Coherence Tomography (OCT). Statistical analysis was performed using the SPSS package.

We evaluated 59 patients; visual complaints were present in 83% and VQL was affected in 92% of them. Of 117 eyes HCVA, Color vision and VF exams were normal in 92%, 82% and 97% respectively; and LCLA was altered in 63%. We found a correlation between NEI-VFQ-25I results and LCLA (r = 0.52 p = 0.013) not found with HCVA or VF exam. OCT was performed in 71 eyes. The RNFL and GCL thinning was found in 50.7% and 58,3% respectively. We found a correlation between RNFL and GCL thickness (r = 0.325, p <0.01) and decreased RNFL thickness with LCLA deterioration (r = - 0.389, p <0.01), as well as between RNFL thickness and HCVA (r = 0.336, p <0.01).

We detected a high percentage of patients with AVP compromise and normal conventional evaluation. Since we found a correlation between LCLA, NEI-VFQ-25I and OCT and demonstrated to be more sensitive parameters of visual disability in MS patients we consider the relevance of its use in clinical practice routine.