Photopic Negative Response Obtained Using a Handheld Electroretinogram Device: Determining the Optimal Measure and...

Area of Science:

• Ophthalmology
• Neuroscience
• Medical Devices

Background:

• The full-field electroretinogram (ERG) is crucial for assessing retinal function.
• The photopic negative response (PhNR) is a key component of the ERG, reflecting inner retinal function.
• Optimizing PhNR measurement repeatability is essential for reliable clinical and research applications.

Purpose of the Study:

• To identify the optimal measure of the photopic negative response (PhNR) for test-retest repeatability.
• To evaluate the repeatability of PhNR measurements using a handheld, nonmydriatic ERG system with self-adhering skin electrodes.
• To assess PhNR repeatability under varying conditions, including different examiners and sessions.

Main Methods:

• Twenty normal participants underwent multiple ERG recordings (200 sweeps each) in both eyes across two sessions.
• The coefficient of repeatability (CoR) was calculated for different PhNR measures and testing conditions.
• Comparisons were made for intra-examiner, inter-examiner, and inter-session variability.

Main Results:

• The PhNR/b-wave peak ratio (PhNR/B) demonstrated the lowest CoR relative to its dynamic range (30 ± 4%).
• No significant changes in the PhNR/B ratio were observed over seven measurements within sessions (P ≥ 0.100).
• No significant differences in CoR were found across different testing conditions (P = 0.314).

Conclusions:

• The PhNR/B ratio is the most reliable measure for minimizing variability in ERG recordings.
• The handheld ERG system and proposed protocols ensure consistent PhNR measurements.
• This technique is suitable for clinical and research use due to its high consistency.