Steady State Pattern Electroretinography (ssPERG) in Age-Related Macular Degeneration (AMD) compared to controls.

Abstract

Purpose: evaluate the ssPERG in eyes with AMD compared to normal controls.

Methods: Nineteen eyes of 19 patients with AMD (7 dry, 12 neovascular or wet) were enrolled. The ssPERGs were recorded from each eye using the Diopsys NOVA System (Diopsys, Inc. Pine Brook, NJ) following best-corrected visual acuity (BCVA) testing. Two concentric field sizes (large and small) were presented during each recording. Concentric field size ratios (CFR) were calculated by dividing the small field magnitude by the large field magnitude. Dry AMD and wet AMD eyes were compared to 24 normal controls. Area-under-curve (AUC) analyses of the ssPERG parameters were performed. One-way ANOVA analysis was used to compare the large field magnitudes and the CFR of the AMD eyes to the controls and linear regression analysis was used to investigate the relationship between the ssPERG and LogMAR BCVA.

Results: Mean LogMAR BCVAs for the groups were 0.139±0.13 (dry AMD), 0.206±0.160 (wet AMD), and 0.034±0.09 (controls). The mean large field magnitude ssPERG responses for the dry (0.97±0.38uV) and wet AMD (1.05±0.45uV) eyes were similar, both significantly less then that of the normal control eyes (1.71±0.48uV), (p=0.028, p=0.005, respectively). The control eyes had a mean CRF of 0.71(±0.14) compared to the dry and wet AMD eyes, 0.91(±0.14) (p=0.019) and 0.91(±0.20) (p=0.005), respectively. The AUC of dry AMD eyes compared to controls was 0.88 (0.71 - 1.00) and the AUC of wet AMD compared to controls was .86 (0.73 - 0.99). Linear regression analysis revealed the following relationship: CFR = 0.715 + 0.891BCVA, (p < 0.0001).

Conclusions: ROC analysis of the ssPERG responses may provide a way to discriminate both dry and wet AMD eyes from healthy eyes. The ssPERG may also be beneficial in detecting early visual function loss due to macular degeneration and may to be prove useful in monitoring the treatment of AMD.

Keywords: 509 electroretinography: clinical • 412 age-related macular degeneration • 585 macula/fovea