Visual dysfunction and neurological disability in multiple sclerosis patients in correlation with the retinal nerve fiber layer and the ganglion cell layer using optical coherence tomography

Aim The aim of this study was to measure retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) complex thickness with Cirrus optical coherence tomography (OCT) in Egyptian multiple sclerosis (MS) patients, and to correlate the OCT findings with the visual functions and neurological conditions. Patients and methods This study design was a cross-sectional one. A total of 40 eyes of 22 MS patients diagnosed according to the McDonald criteria were included in this study. Exclusion criteria were as follows: optic neuritis less than 6 months ago; best-corrected visual acuity (BCVA) less than 0.5; intraocular pressure more than 21 mmHg; cup-to-disc ratio more than 0.5; myopia more than 5 D; and eyes with other ocular or central nervous system diseases. All patients were subjected to the following: full history taking; complete ophthalmic examination, including visual functions (BCVA, color vision, and contrast sensitivity), intraocular pressure, and anterior and posterior segment examination; ophthalmic investigations using the Cirrus OCT (peripapillary RNFL thickness and macular GCL complex thickness); and complete neurological examination containing Expanded Disability Status Scale (EDSS). Results There were statistically significant negative correlations (which is mostly still thickened or biased with BCVA selection) between BCVA and the GCL complex of the superior areas among the studied patients. There were statistically significant negative correlations between color total errors and the GCL complex of the inferior temporal areas among the studied patients. No statistically significant correlations between contrast or EDSS and the GCL complex of any area were found among the studied patients. Conclusion GCL complex thickness is correlated better compared with RNFL thickness in MS patients with their visual functions (mainly color vision with the inferior temporal area of the GCL complex), and visual function is better correlated with them than with neurological disability measured using EDSS.