Electroretinogram

The electroretinogram (ERG) is a diagnostic tool for examining retinal function. Light stimuli are applied and the electrical potentials formed by the retina are recorded using several electrodes. These potentials reflect the electrical activity of the cones and rods as well as the bipolar cells. A distinction is made between scotopic (dark-adapted) and photopic (light-adapted) conditions. In scotopic conditions mainly the rods are tested, in photopic conditions the cones are tested. The investigation is z. B. used in the context of follow-up checks of retinopathia pigmentosa .

In the Ganzfeld electroretinogram, disturbances that only affect the macula are mostly hidden, which is why the multifocal electroretinogram (mfERG) is used if there is a suspicion of disturbance of the central visual field. Here, the patient is offered changing light stimuli for certain areas of the retina and the response curve is calculated separately for each retinal area.

The electroretinogram is also used in zoology - especially in the sensory physiology of animals - to examine the eyes of vertebrates and invertebrates.

See also

• Photoreceptor

Web links

Wiktionary: Elektroretinogramm  - explanations of meanings, word origins, synonyms, translations

Wiktionary: ERG  - explanations of meanings, word origins, synonyms, translations

• Overview of the methods of ophthalmic electrodiagnostics
• Info page of the Eye Center Siegburg

literature

• Franz Grehn: Ophthalmology. Berlin: Springer Verlag, 30th edition, 2008, ISBN 978-3-540-75264-6
• Erwin J. Hentschel, Günther H. Wagner: Dictionary of Zoology , 7th edition, Munich 2004, ISBN 3-8274-1479-2 , page 194, article "Elektroretinogramm"