Study of Stimulus Parameters in Flicker Electroretinogram (ERG)

Study Overview
=================
Brief Summary
-----------------
The electroretinogram (ERG) is a diagnostic test that measures the electrical activity generated by cells in the retina in response to a light stimulus. Typically, an ERG is recorded with white flash when the pupil is dilated. RETeval Visual Diagnostic Device (RETeval) generates an array of color flashes, which allows studying whether color flash would be a useful diagnostic tool. Full pupil dilation is required to obtain a response from the whole retina. However, this requirement often limits a patient's flow in the clinic and increases the overall time patients spend at the eye practitioner. RETeval provides the possibility of recording ERGs in un-dilated pupils therefore making the whole exam easier and shorter. These results need to be compared to the classic, fully dilated ERG and evaluated for efficiency. The purpose of this research study is to use the RETeval device to measure the eye's electrical response and how it changes with different stimuli such as changing flash color or pupil dilation.

Official Title
-----------------
Study of Stimulus Parameters in Flicker Electroretinogram (ERG)

Conditions
-----------------
Retinopathy

Intervention / Treatment
-----------------
* Device: RETeval color flicker ERG
* Device: RETeval dilated versus un-dilated flicker ERG
* Other: pupil dilation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: healthy adult volunteers volunteers able to get their pupil fully dilated Exclusion Criteria: pregnant women children subjects with light sensitivity photosensitive epilepsy allergies or sensitivity to pupil dilation ophthalmic solutions history of glaucoma cardiac dysrhythmia will not be invited to participate in this study. Pregnancy status, light sensitivity and photosensitive epilepsy will be based on volunteer's providing this information at the time of signing the consent form

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: RETeval color flicker ERG<br>Compare implicit times and amplitudes of electroretinograms obtained from series of color flashes to those obtained from white flashes. | Device: RETeval color flicker ERG<br>* Flicker ERGs obtained to 56 CIE 1931 (created by the International Commission on Illumination (CIE) in 1931) colors series. White flash of 0,33, 0,33 was used for comparison.<br>|
| Other: RETeval dilated versus un-dilated flicker ERG<br>Compare implicit times and amplitudes of ERGs obtained from cd/m2/sec stimulation (used with dilated pupils) to those obtained from troland stimulation (used with un-dilated pupils). | Device: RETeval dilated versus un-dilated flicker ERG<br>* Two series of white flashes: 3,0 cd/m2/sec and Trolands equivalent assuming 3,7 mm pupil size, delivered at 3 min interval over 30 min.<br>Other: pupil dilation<br>* Pupil will be dilated using Proparacaine 0.5% and Tropicamide 0.5%<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Flicker harmonic amplitude |  | up to 2 mnths | 
| Flicker harmonic implicit time |  | up to 2 months | 
| Flicker fundamental amplitude |  | up to 2 months | 
| Flicker fundamental implicit time |  | up to 2 months | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Retinal function