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Structure-function relationship between handheld photopic negative response and macular GCIPL thickness in chronic
Yuri Seo1, Dongheon Surl2, Jinu Han3
1Department of Ophthalmology, Gangnam Severance Hospital, Institute of Vision Research, Yonsei University College of Medicine, Seoul, Republic of Korea.
Documenta Ophthalmologica. Advances in Ophthalmology
|June 24, 2026
Summary
Handheld electroretinography (ERG) effectively measures residual retinal ganglion cell function in optic neuropathy. Photopic negative response (PhNR) parameters, especially the W-ratio, correlate with inner retinal structure, aiding clinical assessment.
Area of Science:
- Ophthalmology
- Neuroscience
- Medical Imaging
Background:
- Optic neuropathy (ON) involves progressive damage to the optic nerve, impacting vision.
- Assessing residual retinal ganglion cell (RGC) function is crucial for managing ON.
- Current methods may not fully capture RGC-driven inner retinal function.
Purpose of the Study:
- To evaluate handheld electroretinography (ERG) photopic negative response (PhNR) parameters as indicators of RGC function in chronic ON.
- To correlate ERG-derived functional measures with optical coherence tomography (OCT)-based structural metrics.
Main Methods:
- Retrospective observational study of 27 patients with unilateral chronic ON.
- Handheld full-field photopic ERG (PhNR parameters) and OCT (GCIPL, RNFL thickness) were performed.
- Linear mixed-effects models were used to analyze structure-function relationships.
Main Results:
- ON eyes showed significantly reduced PhNR72, PhNR minimum amplitudes, P-ratio, and W-ratio compared to unaffected eyes.
- The W-ratio demonstrated an independent association with ganglion cell-inner plexiform layer (GCIPL) thickness.
- No significant associations were found with retinal nerve fiber layer (RNFL) thickness or visual field indices.
Conclusions:
- Handheld ERG PhNR parameters, particularly the W-ratio, selectively reflect RGC-driven inner retinal function.
- Portable ERG serves as a practical functional biomarker complementing OCT in chronic ON assessment.
- This approach offers a valuable tool for evaluating residual RGC function.
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