Best-corrected visual acuity and retinal thickness are associated with improved cortical visual processing in treated wet AMD patients

Abstract

Purpose In response to anti-VEGF treatment for wet AMD retinal anatomy and visual acuity is often remedied. In our previous study, we showed that visual evoked potentials (VEP) improve following successful anti-VEGF treatment. The aim of this study was to investigate, how visual acuity and retinal thickness changes are reflected in VEP parameters. Moreover, we wanted to assess the feasibility of VEP as a novel monitoring tool for wet AMD patients. Methods A total of 16 patients and six control subjects were enrolled in this study. Patients received three bevacizumab intravitreal injections. At the beginning of the study and four to 6 weeks after the last injection, the best-corrected visual acuity (BCVA) test, full biomicroscope examination, OCT analysis and VEP were performed. Results In treated eyes, logMAR visual acuity improved on average 0.18 ± 0.32 units, OCT retinal thickness decreased 170 ± 200 micrometres and VEP amplitude increased 1.0 ± 1.4 microvolts. All changes were significant at p < 0.05. There was a significant correlation between the relative changes of VEP amplitude and retinal thickness r = -0.630 (p < 0.05), and between visual acuity (logMAR) and retinal thickness r = 0.576 (p < 0.05). Conclusion We showed that both the increase in VEP amplitude and the improvement in visual acuity are associated with the decrease in retinal thickness in treated wet AMD patients. The results do not indicate additional usefulness of VEP in the diagnosis or monitoring of wet AMD.