Rabin Color Cone Contrast Testing and Retinal Structure in Multiple Sclerosis (P3.227)

OBJECTIVE: Evaluation of computerized cone contrast testing as a rapid, sensitive, quantitative measure of color visual performance in a large cohort of patients with MS. BACKGROUND: Color vision disturbance is a common clinical complaint in patients with MS. To date, color vision testing has suffered from being either of limited quantitative value or being time consuming (or both). The Rabin cone contrast test (RCCT) is a well-established test of cone sensitivity thresholds that is easy to perform in a standard clinical setting, and has never previously been studied in MS. DESIGN/METHODS: We performed Rabin cone contrast testing and spectral domain retinal optical coherence tomography (OCT) in 135 participants with MS (77[percnt] women; 39 with prior optic neuritis). Mixed model linear regression, adjusting for age, sex, history of optic neuritis (ON) and accounting for intra-individual inter-eye correlations was used to analyze associations between cone contrast scores and retinal layer thickness. RESULTS: Lower red, green, and blue color cone contrast test scores on the RCCT were strongly correlated with thinning of both the peripapillary retinal nerve fiber layer (pRNFL) and macular ganglion cell/inner plexiform layer (p<0.001 for both). There was no association between red, green, or blue RCCT scores and the thickness of photoreceptor or outer nuclear layers. CONCLUSIONS: Cone contrast testing is a promising modality for assessing color vision in MS, is strongly associated with ganglion cell injury, and may be complementary to other standard assessments of visual function. It could be easily employed as a relevant functional visual outcome in the MS clinic and additional validation in therapeutic clinical trials is warranted. Disclosure: Dr. Samuel has nothing to disclose. Dr. Yiu has nothing to disclose. Dr. Songster has nothing to disclose. Dr. Bolivar has nothing to disclose. Dr. Gelfand has received personal compensation for activities as a medical-legal consultant. Dr. Gelfand9s wife has received personal compensation for activities with FCB. Dr. Gelfand and his wife have received personal compensation in an editorial capaci Dr. Green has received personal compensation for activities with Novartis, Prana Bioscience, Acorda Therapeutics, Roche Diagnostics Corp., and Biogen Idec.