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

Abstract

<b><i>Background:</i></b> 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. <b><i>Summary:</i></b> 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 (<i>n</i> = 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; <i>p</i> = 0.02) and b-wave amplitude (WMD: −28.70 μV; 95% CI: −51.40 to −6.01 μV; <i>p</i> = 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; <i>p</i> = 0.02), reduced b-wave amplitude (WMD: −13.26 μV; 95% CI: −18.64 to −7.88 μV; <i>p</i> &#x3c; 0.0001), and longer b-wave implicit time (WMD: 0.69 ms; 95% CI: 0.30–1.08 ms; <i>p</i> = 0.0006). Subgroup analyses found that these changes were only statistically significant in eyes with late AMD, not early AMD. <b><i>Key Messages:</i></b> 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.