Procedures & Services > Diagnostic Testing > Electroretinogram (ERG)

Your eyes will be dilated for this test. We ask that you do not apply creams, lotions or cosmetics the day of testing. You will be placed in a darkened room and allowed to adapt to the dark for 30 to 40 minutes.

An electrode will be placed on your forehead and special contact lenses with electrodes will be into your eyes after a topical numbing drop has been applied. During the test, you will place your chin into a chin rest that is attached to a special lighted bowl and several sequences of bright flashes of light will occur. After the initial series of light flashes, the room will be lightened for a final series of flashes. There may be slight discomfort from wearing the lenses, especially if you are not a routine lens wearer. Please allow one to two hours for testing.