Comparing the RETeval portable ERG device with more traditional tabletop ERG systems in normal subjects and selected retinopathies.

Purpose: Our study aimed to determine if ISCEV standard-like ERGs recorded with the LKC RETeval portable ERG unit compared to those obtained using the more traditional tabletop unit.

Methods: ERGs recorded from normal subjects and patients affected with retinal ON and OFF pathway anomalies were compared. Analysis included peak time and amplitude measurements as well as time-frequency domain analysis with the discrete wavelet transform of waveforms obtained with the two systems.

Results: Although both systems were similarly able to record reliable and highly reproducible ERG responses, there were major discrepancies in ERG responses between the portable and tabletop units, pointing toward a weaker stimulation of the retinal OFF pathway with the portable RETeval unit.

Conclusion: The portable RETeval unit appears to be able to record highly reproducible and diagnostically useful clinical ERGs, albeit with some significant differences in waveform composition compared to those obtained with more standard tabletop systems. Given the unknown origin of these waveform discrepancies, if left uncorrected, these differences could potentially lead to erroneous interpretation when used in the clinical context and/or compared to ERGs recorded using more traditional table top units. Clearly, more research is warranted before handheld devices, such as the RETeval, can be homologated as a diagnostically sound ERG devices.