Optimising PhNR recording for paediatric testing
Research type
Research Study
Full title
Optimising methodology for recording the Photopic Negative Response of the Electroretinogram for Children
IRAS ID
264782
Contact name
Oliver R Marmoy
Contact email
Sponsor organisation
Manchester Metropoliton University
Duration of Study in the UK
2 years, 1 months, 17 days
Research summary
The Electroretinogram (ERG) is a test measures responses from cells in the retina to a flashing light. Recently, the International Society for Clinical Electrophysiology of Vision (ISCEV) published standards for recording the Photopic Negative Response (PhNR), but these aren’t child-friendly because they require pupil dilation with drugs, corneal electrodes (fine wires which touch the eye surface), ten minutes light adaptation (sitting still for ten minutes in bright light) whilst still looking into a large ‘ganzfeld’ white bowl. The PhNR is a relatively new way of clinically examining the function of the nerve cells (retinal ganglion cells) in the eye which is particularly useful in patients who have neurological or nerve disease of the eye.
At GOSH, we record our other types of ERG using a local, but well published, ‘child friendly’ protocol using a hand-held flash light, skin electrodes and no pupil dilation, which give similar results. To date, however, there has been no research to see if we can effectively modify the recent ISCEV standard PhNR protocol in line with our existing tests, to be more child friendly, which is the aim of this study.
We intend to record the PhNR in healthy adult volunteers during one to two visits using a modified ‘paediatric’ protocol, to see if our local technique can be adapted successful to recording a PhNR. We will do this in three stages. First (1) we will need to establish the ideal flash strength which makes the largest PhNR response. Secondly (2), we need to work out the optimum time between flashes we can use without affecting the PhNR (faster=better for children to reduce time needing to sit still). Lastly (3), we need to work out the variation of the PhNR in this modified protocol between and within the same individuals (‘inter- and intra-subject variability’).
REC name
South Central - Berkshire Research Ethics Committee
REC reference
20/SC/0345
Date of REC Opinion
11 Sep 2020
REC opinion
Further Information Favourable Opinion