Electroretinography 3 JAX_ERG_003

Jump to:

Purpose

Full-field electroretinogram (ERG) is a mass electrical response of the retina to a light stimulus. The ERG contains four components: a-wave, b-wave, c-wave and FO-wave. These four components reflect the responsiveness of retinal photoreceptor cells and other neurons as a measure of visual function.

Experimental Design

 

Equipment

Celeris - Diagnosys LLC

Procedure

Procedure

  1. Transfer mice from the animal room to the testing room.
  2. Mice are dark adapted overnight (alternatively: minimum of 2 hours) for testing procedures.
    1. All rod testing procedures are done under dim red light after a minimum 2-hour dark adaptation period
  3. Following dark adaptation one drop of an appropriate mydriatic solution is applied to each eye to induce pupil dilation.
  4. Once the pupils have dilated mice are anesthetized with the inhalation of 2% Isoflurane.
  5. When the mouse has reached the proper plane of anesthesia, the mouse is placed on a heated platform and the nose is placed in the nose cone for continuous anesthetic inhalation.
  6. An appropriate opthalmic lubricant is applied to the electrodes before placing on each cornea.
  7. The scotopic test is performed with pulsing white light.
  8. A 3-minute light-adaptation follows before the photopic test is run. At this time an additional drop of opthalmic lubricant should be added to each eye without adjusting the electrodes.
  9. After 3 minutes of light adaptation, photopic ERGs are obtained with brighter white flashes at varying stimulation intensities.
  10. Once the photopic test is complete, carefully remove the recording electrodes and apply a generous amount of an ophthalmic gel to both eyes and allow the mouse to recover in a clean heated pen until fully conscious.
  11. Return the mouse to its home pen.
  12. Clean the electrodes with sterile water followed by 70% ethanol.
  13. Save the test results and export to the server.

Notes

Amplitude and timing measures of the ERG waveform are taken:

  1. The a-wave amplitude is measured from the pre-stimulus baseline to the lowest negative trough; the b-wave amplitude is measured from the trough of the a-wave to the following highest peak; the c-wave amplitude is measured from the pre-stimulus baseline to the following highest peak; the FO- wave amplitude is measured from the peak of the c-wave to the subsequent lowest trough.
  2. Implicit time (t) is measured from stimulus onset to the trough or peak of each wave.

Parameters & Metadata

Filter:

Name Version Type Description Req. Upload Req. Analysis Annotation Increment Options Ontology Options Unit Data Type Derived History Key Group ID
Name Version Type Description Req. Upload Req. Analysis Annotation Increment Option Ontology Options Unit Data Type Derived History Key Group ID