Full‐field electroretinography in age‐related macular degeneration: an overall retinal response

Abstract

Purpose Age‐related macular degeneration (AMD) is generally considered a disease of the macula. However, recent studies show peripheral retinal lesions are prevalent in patients with AMD, indicative of a disease process that is more widespread. Full‐field electroretinography (ffERG) measures an electrical response, not only from the macula, but from the entire retina. We wanted to study the ffERG response in eyes with AMD. Methods We performed full‐field electroretinography (RETI‐port/scan 21, Roland, Berlin) in 13 patients with early AMD, 25 patients with late AMD and 24 individuals without vitreoretinal disease as a control group. Dawson–Trick–Litzkow fibre electrodes were used. Statistical analysis was performed and a p‐value <0.05 was considered significant. Results After adjusting for multiple comparisons, both the light‐adapted 3.0 a‐wave implicit time (p < 0.001) and 30‐Hertz flicker peak time (p = 0.012) showed significant difference between patients with late AMD and individuals without vitreoretinal disease. There was a significant difference in the light‐adapted 3.0 a‐wave implicit time (p = 0.011) between patients with early AMD and the control group, but the difference in 30 Hz flicker peak time was not significant (p = 0.256). Conclusion The difference in cone function measured by light‐adapted 3.0 a‐wave implicit time and 30‐Hertz flicker peak time in early and late AMD when compared to healthy controls suggests a more diminished overall response when AMD has reached later stages.

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

“…There were no differences in light-adapted a-wave and b-wave amplitudes and implicit times [13]. Forshaw et al [2] compared patients with early AMD and patients with late AMD with a healthy control group. There were no differences in the dark-adapted a-wave and b-wave amplitudes and implicit times between the groups, but in the light-adapted responses the 3.0 a-wave implicit times were significantly prolonged in patients with early AMD and late AMD [2].…”

“…Forshaw et al [2] compared patients with early AMD and patients with late AMD with a healthy control group. There were no differences in the dark-adapted a-wave and b-wave amplitudes and implicit times between the groups, but in the light-adapted responses the 3.0 a-wave implicit times were significantly prolonged in patients with early AMD and late AMD [2]. Thirty Hertz flicker peak times were significantly prolonged in the late AMD group compared to the control group [2].…”

“…Age-related macular degeneration (AMD) is the most common cause of irreversible vision loss in the Western World [1]. AMD is often described as a form of exaggerated retinal aging, as even normal aging leads to a decline in retinal function [2]. Hallmarks of early AMD are drusen and changes to the retinal pigment epithelium, characteristics that are thought to be present in 8.0% of individuals aged 45 years or more [1].…”

“…ffERG can therefore investigate the impact of peripheral retinal lesions leading to a better understanding of overall retinal function in AMD. Modern ERG makes use of the International Society for Clinical Electrophysiology of Vision (ISCEV) standardized protocol that enables the comparison of data from different laboratories around the world [7] and while studies are showing that patients with AMD have an impaired overall retinal response [2], academic and clinical consensus regarding this has yet to be reached. The purpose of our study was therefore to systematically review the literature and perform meta-analyses to map and investigate possible differences in ffERG between patients with AMD and healthy individuals.…”

The potential of marine resources for retinal diseases: a systematic review of the molecular mechanisms

“…Consequently, ERG is not standard in the assessment of retinal dysfunction in AMD (Gerth 2009). However, prolonged ERG latency in the a-wave in light-adapted flicker ERG may be an indicator of the progression of AMD (Forshaw et al 2020).…”