Optical blur effects on pattern & focal ERG in healthy eyes (V1.0).
Research type
Research Study
Full title
The value of comparing standard pattern and focal electroretinography under different conditions of optical blur in healthy adult participants.
IRAS ID
342012
Contact name
Anthony G. Robson
Contact email
Sponsor organisation
Research and Development Office, Moorfields Eye Hospital NHS Foundation Trust
Duration of Study in the UK
0 years, 5 months, 13 days
Research summary
Pattern electroretinogram (PERG) is a valuable test used to assess macular and retinal ganglion cell (optic nerve) function, to aid diagnostic assessment of retinal and neurological disease. The PERG is generated by a high contrast checkerboard stimulus (black and white checks display on a monitor; during recording, the checks reverse - black turns into white, and white turns into black), this checkerboard pattern can be attenuated by defocus, which affects the stimulus contrast. Optical defocus can therefore confound interpretation of a reduced PERG response, and the ability to reliably assess retinal function. The current International Society for Clinical Electrophysiology of Vision (ISCEV) Standard for PERG emphasises the need for optimal correction to accurately assess retinal responses.
Although used locally at Moorfields Eye Hospital, the focal electroretinogram (FERG; of 4 squares) is not widely used in other laboratories, however the FERG is now recognised as a potentially useful adjunct to standard pattern ERG testing by the current ISCEV standards updated and published in 2024. The PERG responses are markedly altered (amplitude reduction and/or shift in peak time) in a significant number of patients who attend unrefracted or forget to bring their spectacles. Such alterations can confound reliable assessment of central macular dysfunction, potentially leading to diagnostic inaccuracies, or the need for repeat testing, causing delay in clinical management.
The relationship between the degree of optical blur and relative influence on PERG and FERG is not fully understood. It would be advantageous to quantify the relative effect of optical blur on both types of response (to PERG and FERG pattern) in order to minimise measurement uncertainty and to inform interpretation in a healthy adult population.REC name
London - Riverside Research Ethics Committee
REC reference
24/PR/1333
Date of REC Opinion
13 Nov 2024
REC opinion
Further Information Favourable Opinion