Global Information Lookup Global Information

Electroretinography information


Electroretinography
Maximal response ERG waveform from a dark adapted eye.
ICD-9-CM95.21
MeSHD004596
[edit on Wikidata]
Schematic Electroretinography waves of healthy people.

Electroretinography measures the electrical responses of various cell types in the retina, including the photoreceptors (rods and cones), inner retinal cells (bipolar and amacrine cells), and the ganglion cells. Electrodes are placed on the surface of the cornea (DTL silver/nylon fiber string or ERG jet) or on the skin beneath the eye (sensor strips) to measure retinal responses. Retinal pigment epithelium (RPE) responses are measured with an EOG test with skin-contact electrodes placed near the canthi. During a recording, the patient's eyes are exposed to standardized stimuli and the resulting signal is displayed showing the time course of the signal's amplitude (voltage). Signals are very small, and typically are measured in microvolts or nanovolts. The ERG is composed of electrical potentials contributed by different cell types within the retina, and the stimulus conditions (flash or pattern stimulus, whether a background light is present, and the colors of the stimulus and background) can elicit stronger response from certain components.[citation needed]

If a dim flash ERG is performed on a dark-adapted eye, the response is primarily from the rod system. Flash ERGs performed on a light adapted eye will reflect the activity of the cone system. Sufficiently bright flashes will elicit ERGs containing an a-wave (initial negative deflection) followed by a b-wave (positive deflection). The leading edge of the a-wave is produced by the photoreceptors, while the remainder of the wave is produced by a mixture of cells including photoreceptors, bipolar, amacrine, and Müller cells or Müller glia.[1] The pattern ERG (PERG), evoked by an alternating checkerboard stimulus, primarily reflects activity of retinal ganglion cells.

  1. ^ Perlman, Ido. "The Electroretinogram: ERG by Ido Perlman". Webvision at University of Utah. Archived from the original on 2015-12-28.

and 24 Related for: Electroretinography information

Request time (Page generated in 0.5971 seconds.)

Electroretinography

Last Update:

Electroretinography measures the electrical responses of various cell types in the retina, including the photoreceptors (rods and cones), inner retinal...

Word Count : 1249

Electrogram

Last Update:

An electrogram (EGM) is a recording of electrical activity of organs such as the brain and heart, measured by monitoring changes in electric potential...

Word Count : 375

Achromatopsia

Last Update:

as achromats exhibit a complete absence of cone cell activity via electroretinography in photopic lighting. There are at least four genetic causes of achromatopsia...

Word Count : 2928

Nyctalopia

Last Update:

088807. PMC 2516064. PMID 18660533. Witzel CA, Joyce JR, Smith EL. Electroretinography of congenital night blindness in an Appaloosa filly. Journal of Equine...

Word Count : 1073

Retinitis pigmentosa

Last Update:

presentation and course. Furthermore, there was greater preservation in electroretinography amplitudes than the more prevalent Pro23His mutation. Autosomal recessive...

Word Count : 6401

Medical procedure

Last Update:

Electromyography Electroneuronography Electronystagmography Electrooculography Electroretinography Endoluminal capsule monitoring Endoscopy Colonoscopy Colposcopy Cystoscopy...

Word Count : 572

List of medical tests

Last Update:

Smear tests such as Pap smears dilated fundus examination multifocal electroretinography (mfERG) optical coherence tomography (OCT) visual field test polysomnography...

Word Count : 298

Acute zonal occult outer retinopathy

Last Update:

associated with photopsia, minimal funduscopic changes and abnormal electroretinography findings. This retinal disease was first described by Donald Gass...

Word Count : 185

Ophthalmology

Last Update:

angiography to visualize the vascular networks of the retina and choroid. Electroretinography (ERG) measures the electrical responses of various cell types in...

Word Count : 5317

Cataract surgery

Last Update:

topography Electrodiagnosis Electronystagmography Electrooculography Electroretinography Fluorescein angiography Fundus photography Heidelberg Retinal Tomography...

Word Count : 15154

Eye examination

Last Update:

computed tomography Scanning laser polarimetry Electrooculography Electroretinography Ultrasound biomicroscopy Maddox rod Brock string Convergence Testing...

Word Count : 2079

Ursodoxicoltaurine

Last Update:

days from post-natal day 6 (p6) to p30 and compared to the vehicle. Electroretinography (ERG), photoreceptor cell counts, cone photoreceptor nuclei counts...

Word Count : 1526

Retina

Last Update:

dark-adapted visual thresholds, vascular diameters, pupillometry, electroretinography (ERG), multifocal ERG and optical coherence tomography (OCT). This...

Word Count : 9293

Electrocardiography

Last Update:

heart Electroencephalography Electrogastrogram Electropalatography Electroretinography Emergency medicine Forward problem of electrocardiology Heart rate...

Word Count : 9808

Electrophysiology

Last Update:

common electrooculography EOG eye—entire globe 2—somewhat common electroretinography ERG eye—retina specifically 2—somewhat common electronystagmography...

Word Count : 4430

Idebenone

Last Update:

experiments with mice. In humans, evaluation of Surrogate endpoints like electroretinography, auditory evoked potentials and visual analogue scales also suggested...

Word Count : 1513

Chloroquine retinopathy

Last Update:

electroretinography (paracentral depressions) may be obtained. Profound abnormalities detected with visual field and multifocal electroretinography testing...

Word Count : 641

Stargardt disease

Last Update:

retinal pathology. Spectral-domain optical coherence tomography, electroretinography and microperimetry are also useful for diagnostic and prognostic...

Word Count : 2814

Hydrodissection

Last Update:

topography Electrodiagnosis Electronystagmography Electrooculography Electroretinography Fluorescein angiography Fundus photography Heidelberg Retinal Tomography...

Word Count : 218

Evoked potential

Last Update:

negativity Event-related potential Evoked field Electroencephalography Electroretinography Slow vertex response Event-related potential N100, N200, N2pc, N170...

Word Count : 5213

Appaloosa

Last Update:

December 12, 2010. Witzel, C.A.; Joyce, J.R.; Smith, E.L. (1977). "Electroretinography of congenital night blindness in an Appaloosa filly". Journal of...

Word Count : 7231

Capsulorhexis

Last Update:

topography Electrodiagnosis Electronystagmography Electrooculography Electroretinography Fluorescein angiography Fundus photography Heidelberg Retinal Tomography...

Word Count : 562

Usher syndrome

Last Update:

characteristic chromosomal mutations. An alternative approach is electroretinography, although this is often disfavored for children, since its discomfort...

Word Count : 3585

Cone dystrophy

Last Update:

and the difficulty in making the diagnosis in the early stages, electroretinography (ERG) remains the best test for making the diagnosis. Abnormal cone...

Word Count : 1318

PDF Search Engine © AllGlobal.net