Frequently Asked Questions &


Frequently Asked Questions

Prepping the skin takes 2-3 minutes. For light adapted testing (the most commonly used), ERG protocols vary in length but are as short as 15 seconds per eye. Test time will be extended if more than 1 protocol is used in succession.  

Dark adapted testing, used to asses rod function, requires 20 minutes of dark adaptation prior to starting a test.   

Yes, however, excessive blinking may slightly extend the test duration. 

Non-mydriatic testing allows you to complete ERG testing without having to dilate the patient’s pupils.  This can be beneficial in reducing the overall time for the test, not subjecting the patient to the downsides of dilation, and better fitting into the patient flow of your practice. 

The RETeval device has a built in pupillometer that dynamically measures and compensates for pupil size to create consistent retinal stimulation for non-mydriatic testing. 

This means dilation is not required for the most commonly used protocols

Yes. The only caveat is the pupil must fit inside the green circle and not be obscured by the eyelid.

No. The charging cradle needs to be connected to a computer to download PDF reports but a connection to a computer is not required during testing. 

For about 8 hours or 70 tests. Most customers store the hand-held device in the charging cradle so this is never an issue. 

Is there an aged-matched normative database?

Yes, over 500 subjects for most protocols.

Yes. RETeval does have the capability of running a Flash VEP. A VEP kit (sold separately) is required. Please note that the Flash VEP protocol does not have normative data and only provides an indication that the signal from the retina is reaching the primary visual cortex.  

Yes. Color coded results are included for all protocols that use normative data.

The device is easy to un-box and simple to set up. Online video training is provided by Konan’s learning management system (LMS) which is supplemented by one-on-one remote training with one of Konan’s Application Specialists.

It is quick and easy to sanitize using at 70% isopropyl alcohol and no additional cleaning is required specifically for COVID-19.

RETeval qualifies for CPT Codes 92273 (ffERG) and 95930 (VEP). Reimbursement policies vary between payors.


Light source (LED):   
Dynamic flash luminance energies (cd⋅s/m²)  Background luminance (cd/m²)
- Red (621 nm)
- Green (530 nm) 
- Blue (470 nm) 
- White (RGB) 
Input Type
< 0.1 µV at the flicker frequency for flicker protocols 
> 100 dB at 50-60 Hz 

Frequency Range

Flicker Frequency
Approximately 28.3 Hz

Data Resolution
Approximately 71 nV / bit 

Input Range
±0.6 V 

Timing accuracy†: (electronic eye) 
< ±0.1 ms 

Timing precision†: (human eye, 1σ) 
Typically < ±1 ms 

Pupil measurements
1.3 mm – 9.0 mm, < 0.1 mm resolution, 28.3 Hz 

Complies with optical, electrical, and biocompatibility safety standards

FDA 510(k) cleared
CE Marked