Quantitative cone contrast threshold testing in patients with differing pathophysiological mechanisms causing retinal diseases

Abstract

Background Cone contrast threshold testing (CCT) provides quantitative measurements of color and contrast function to reveal changes in vision quality that are not standard endpoints in clinical trials. We utilize CCT to measure visual function in patients with multiple sclerosis (MS), age-related macular degeneration (AMD), epiretinal membrane (ERM), and retinal vein occlusion (RVO). Methods Retrospective data was gathered from 237 patients of the Gavin Herbert Eye Institute. Subjects included 17 patients with MS, 45 patients with AMD, 41 patients with ERM, 11 patients with RVO, and 123 healthy controls. Patients underwent the primary measurement outcome, CCT testing, as well as Sloan visual acuity test and spectral domain optical coherence tomography during normal care. Results Color and contrast deficits were present in MS patients regardless of history of optic neuritis. AMD with intermediate or worse disease demonstrated reduced CCT scores. All 3 stages of ERM demonstrated cone contrast deficits. Despite restoration of visual acuity, RVO-affected eyes demonstrated poorer CCT performance than unaffected fellow eyes. Conclusions CCT demonstrates color and contrast deficits for multiple retinal diseases with differing pathophysiology. Further prospective studies of CCT in other disease states and with larger samples sizes is warranted.