The Diagnostic Accuracy of the Photopic Negative Response (PhNR)
Research type
Research Study
Full title
The diagnostic accuracy of broadband versus narrowband photopic negative responses
IRAS ID
285508
Contact name
Shaun Leo
Contact email
Sponsor organisation
Moorfields Eye Hospital NHS Foundation Trust
Clinicaltrials.gov Identifier
000, 000
Duration of Study in the UK
0 years, 6 months, 0 days
Research summary
In Ophthalmology, electrodiagnostic tests detect signals that are produced by the retina, optic nerve and brain in response to visual stimulation, such as a flash of light. These tests provide valuable objective information about the function of certain cells in the visual system.
This study aims to establish the most clinically suitable protocol from a choice of two types of the same test, both a form of electroretinogram (ERG), which is a recording of the electrical responses from the retina at the back of the eye. This is similar to the way that the ECG (electrocardiogram) is a recording of signals from the heart. The test in question is known as the photopic negative response (PhNR) and it is a measure of the function of retinal ganglion cells (RGCs), which are nerve cells in the inner retina.
The first PhNR stimulus used in this study would be a flashing white light (W/W) that is already validated and used routinely for clinical work. The second type of PhNR is also a flashing light, but instead of being white, it would be a red flash with a constant, blue background (R/B). There is some evidence to suggest that the red-on-blue protocol may be superior for the diagnosis of specific cohorts of patients with Glaucoma. We would like to further investigate this finding to determine which test is the most suitable for use in a diverse group of adult patients attending our outpatient clinic.REC name
Wales REC 6
REC reference
20/WA/0300
Date of REC Opinion
5 Nov 2020
REC opinion
Favourable Opinion