Contrast Sensitivity Changes in Center Involving Diabetic Macular Edema Treated with Aflibercept

PURPOSE: To characterize the changes in contrast sensitivity (CS) and retinal anatomy in patients with center involving diabetic macular edema (CDME) measured from baseline to post-loading doses of aflibercept. PATIENTS AND METHODS: This single center, prospective, open-label, non-controlled evaluation of five aflibercept intravitreal injections for treatment of CDME over a 16-week period. One eye in each of the forty patients will receive aflibercept every 4 weeks. Subject testing includes measurements of central retinal thickness (CRT), best corrected visual acuity (BCVA), Pelli–Robson (PR) CS, and CamBlobs (CB) CS at 20 weeks post baseline. RESULTS: A total of 40 eyes from 40 patients with CDME were analyzed. The mean age was 62.9 ±10.6 years and 55% were male. At baseline, CRT was 365 ±94.6µm with logMAR BCVA 0.25±0.20. CS PR at baseline was 1.46±0.13 logCS compared to the normal population 1.79±0.10 logCS (P=<0.01), and the CS CB was 1.55±0.16 logCS compared to 1.92±0.08 logCS in the normal population (P=<0.01). At the completion of the study, CRT was decreased to 289 ±43.7µm (P=<0.001), and the logMAR BCVA improved to 0.18±0.02 (P=<0.05). At the same point the CS PR was 1.52±0.16 and CS CB was 1.62±0.16 logCS. At the end of the study 85% of eyes obtained BCVA of 0.3 logMAR or better. There was a reduction from baseline of 82.5% to 57.5% in the number of patients that had a CS that was two standard deviations below the mean. The greatest improvement in CS was associated with those patients that had the greatest reduction in CRT. CONCLUSION: CS impairment in patients with CDME is significant. Although treatment can be associated with improvement, there still remains a group with decreased CS that could impact activities of daily living. Earlier intervention using reduction in CS as a metric may be associated with reduced residual deficit associated with treatment.