Optimal RF-ERG

  • Research type

    Research Study

  • Full title

    Investigating the optimal red-flash ERG strength after 20-minutes of dark adaptation in healthy adults

  • IRAS ID

    337851

  • Contact name

    Eduardo Normando

  • Contact email

    e.normando@nhs.net

  • Sponsor organisation

    Imperial College London

  • Duration of Study in the UK

    0 years, 8 months, 1 days

  • Research summary

    Research Summary:

    This study investigated the most appropriate strength of a red light flash for measuring retinal function using an eye test called an electroretinogram (ERG), which records the electrical responses of the retina to light.

    We found that stronger red light flashes produced larger retinal responses and faster response times. Several flash strengths performed well, but a flash strength of 0.25 candela-seconds per square metre (cd·s/m²) provided the best overall performance. Flash strengths between 0.2 and 0.6 cd·s/m² produced responses that were similar to those obtained using the standard dim white flash currently used in clinical testing.

    We also examined whether age affected test results. No meaningful differences were found between younger and older participants, suggesting that age does not have a significant impact on this red flash ERG test.

    These findings suggest that a red flash strength of approximately 0.25 cd·s/m² may be a useful option for assessing retinal function and could help support future clinical and research applications of the test.

    Visual electrophysiology is a group of diagnostic tests which provides information on the function of the visual pathway. The electroretinogram or electroretinography (ERG) is a type of visual electrophysiology test that measures the electrical response of cells in the retina. The retina is located at the back of the eye and its function is to capture light and transmit an electrical signal for the brain to perceive a visual image. The retina consists of many types of cells. Therefore, there are different types of ERG that can target areas of the retina or types of retinal cells. In this study the type of ERG that will be investigated is called the dark adapted red-flash ERG. During this test, a flash of red light is used in eyes that have been dark adapted (20 minutes in a dark room). Current research on the impact of red flash strength on waveform optimisation is sparse, leading to variability in protocols across different centres. This study aims to fill this gap by identifying the red flash strength that elicits the most optimal waveform after 20 minutes of dark adaptation in healthy adults.

  • REC name

    South West - Cornwall & Plymouth Research Ethics Committee

  • REC reference

    24/SW/0118

  • Date of REC Opinion

    22 Oct 2024

  • REC opinion

    Further Information Favourable Opinion