Full-Field Electroretinography Changes Associated with Age-Related Macular Degeneration: A Systematic Review with Meta-Analyses

Abstract

Background: The aim of this study was to systematically review the literature and to perform meta-analyses on full-field electroretinography (ffERG) between healthy controls and age-related macular degeneration (AMD) to map the extent of retinal dysfunction.

Summary: We systematically searched 11 databases on 3 March 2021. Eligible studies had to measure retinal function using ffERG in eyes with AMD and in healthy controls. We extracted data on a-wave and b-wave function in dark- and light-adapted ffERG and calculated summary estimates on differences between eyes with AMD and controls using weighted mean differences (WMD). Subgroup analyses were made for early and late AMD. Six studies (n = 481 eyes) were eligible for review (301 with any AMD, 180 controls). For dark-adapted data, any AMD was associated with reduced a-wave amplitude (WMD: -17.16 μV; 95% CI: -31.79 to -2.52 μV; p = 0.02) and b-wave amplitude (WMD: -28.70 μV; 95% CI: -51.40 to -6.01 μV; p = 0.01). For light-adapted data, any AMD was associated with longer a-wave implicit time (WMD: 0.92 ms; 95% CI: 0.12-1.72 ms; p = 0.02), reduced b-wave amplitude (WMD: -13.26 μV; 95% CI: -18.64 to -7.88 μV; p < 0.0001), and longer b-wave implicit time (WMD: 0.69 ms; 95% CI: 0.30-1.08 ms; p = 0.0006). Subgroup analyses found that these changes were only statistically significant in eyes with late AMD, not early AMD.

Key messages: Reduced retinal function on ffERG is present in eyes with AMD, in particular those with late AMD. These findings suggest that AMD is a pan-retinal disease with AMD-associated photoreceptor dysfunction beyond the macula.

Keywords: Age-related macular degeneration; Full-field electroretinography; Functional testing; Peripheral retina.