Measuring differences in the ERG in myopia using the RETeval device with skin electrodes

Area of Science:

• Ophthalmology
• Neuroscience
• Biomedical Engineering

Background:

• Previous studies indicate reduced and delayed electroretinogram (ERG) responses in non-pathological myopia.
• Traditional ERG methods involve invasive electrodes and cumbersome equipment, limiting widespread clinical use.
• This study explores the feasibility of using non-invasive skin electrodes and a handheld ERG device to assess myopia-related ERG changes.

Purpose of the Study:

• To investigate if non-invasive skin electrodes and a handheld ERG device can detect previously reported ERG alterations in myopia.
• To compare ERG responses between individuals with non-pathological myopia and non-myopic controls using novel technology.

Main Methods:

• Monocular flash electroretinograms (ERGs) were recorded using the RETeval® device with Sensor Strip skin electrodes.
• The study included 46 participants with non-pathological myopia and 47 non-myopic controls.
• Measurements followed the 'ISCEV 6 Step Dark First cd' protocol under pupil mydriasis.

Main Results:

• A statistically significant delay in median dark-adapted (DA) implicit times was observed in myopic participants for DA 3.0 A-wave, DA 10.0 A-wave, B-waves, and DA Oscillatory potentials 1 and 2.
• No significant differences in light-adapted (LA) implicit times or response amplitudes were found between the refractive groups.
• A significant positive correlation was identified between axial length (AL) and DA implicit times in all DA components.

Conclusions:

• The RETeval® device with skin electrodes detected subtle DA implicit time delays in myopia, consistent with prior research.
• This non-invasive approach did not detect reduced ERG amplitudes, possibly due to inter-subject variability or skin electrode artifacts.
• The absence of differences in LA implicit times suggests potential underlying differences in dark-adaptation or scotopic pathways in myopia.