Effectiveness of Time Domain and Spectral Domain Optical CoherenceTomograph to Evaluate Eyes with And Without Optic Neuritis in MultipleSclerosi Patients

Abstract Purpose: To compare the macular assessment and retinal nerve fiber layer (RNFL) thickness by using two different optical coherence tomographies (OCTs): a time domain (TD) and a spectral domain (SD) OCT, in multiple sclerosis (MS) patients with and without unilateral optic neuritis (ON). Methods: We enrolled 34 patients (13 males and 21 females): 18 without previous episodes of ON and16 with a previous monolateral episode of ON occurred at least 3 months prior to examination. Patients underwent ophthalmological examination, TD OCT and SD OCT scans. We compared the outcomes of eyes with and without ON by using Student’s t test. Results: In the affected eye group a reduction of the average RNFL was found using TD OCT (reduction of 22.8%) with the difference between the two groups being statistically significant (p<0.05) in almost all the investigated retina areas. Similar results were found when eyes were analysed with SD OCT, also when the ganglion cell layer (GCC) was considered: a reduction of 18.1% of GCC average thickness was found. No significant difference was found when the outer retina was considered. Conclusions: In MS patients both OCT systems were able to detect a difference between eyes with an outcome of optic neuritis and those without optic neuritis.