ERG; Electrophysiologic testing

Electroretinography is a test to measure the electrical response of the eye's light-sensitive cells, called rods and cones. These cells are part of the retina (the back part of the eye).

Contact lens electrode on eye

The electroretinography (ERG) test measures the electrical response of the retina to light. It is performed by placing an electrode on the cornea of the eye after it has been numbed with eye drops. Disorders of the retina can be evaluated with this test. It can also help to determine if retinal surgery may be helpful.

How the Test is Performed

How to Prepare for the Test

How the Test will Feel

Why the Test is Performed

Normal Results

What Abnormal Results Mean