WHAT IS ELECTRORETINOGRAPHY?
Electroretinography
(ERG) is a computerized technique that we use to measure the function of the
retina. With the patient sedated, 2 small reference electrodes are placed under
the skin, one on the orbital bone, one on the bridge of the nose, and a contact
lens electrode is placed on the cornea. With the room lights off, a light
source is periodically flashed into the eye to stimulate an electrical response
from the retina. The information is gathered by the electrodes and processed by
the computer, which creates a waveform. The waveform is comprised of 2 main
waves – A and B. Basically, these waves directly reflect the activity of the
photoreceptor cells in the retina.