Electroretinography

electroretinography

Electroretinography is a medical test that records the electrical activity produced by the retina, the light-sensitive layer at the back of the eye. During the test, brief flashes or patterns of light stimulate the retina while electrodes placed on the eye surface or nearby skin pick up the tiny electrical signals the retinal cells generate. The test captures how well different groups of retinal cells—such as rods for dim light and cones for color and detail—respond to light, producing a waveform that clinicians can interpret. This test matters because it provides an objective measurement of retinal function, even when the eye looks normal during a routine exam. Doctors use it to diagnose inherited retinal diseases, monitor progression, and check for damage from medications or other conditions. There are variations, like full-field and multifocal recordings, that focus on overall retinal function or on specific regions. The procedure is generally safe and noninvasive, though it can be uncomfortable for people sensitive to bright flashes or who need pupil dilation.