Featured Article for November 30, 2020
Electroretinogram
The electroretinogram (ERG) is a diagnostic test that measures the electrical activity of the retina in response to a light stimulus. The ERG arises from currents generated directly by retinal neurons in combination with contributions from retinal glia. Importantly, the ERG is an objective measure of retinal function that can be recorded non-invasively under physiological conditions. ERGs are often recorded using a thin fiber electrode that is placed in contact with the cornea or an electrode that is embedded within a corneal contact lens. These electrodes permit the electrical activity generated by the retina to be recorded at the corneal surface. The ERG can be elicited by diffuse flashes or patterned stimuli. The International Society for Clinical Electrophysiology of Vision (ISCEV) has introduced standards for the different forms of ERG recordings. The ERG has important clinical utility, in that it provides diagnostic information concerning a variety of inherited and acquired retinal disorders. Moreover, the ERG can be used to monitor disease progression and evaluate retinal toxicity due to various drugs or retained intraocular foreign bodies.
