Characterizing the C-Wave of the Electroretinogram
The c-wave of the electroretinogram is a slow cornea-positive response which must be recorded by d.с. -amplification. It is generated in part by the pigment epithelium but also by the Müller cells and inner retina. The amplitude and waveform of the c-wave are quite variable which complicates its definition for clinical use. Both c-wave amplitude and time-to-peak increase with stimulus energy, and the c-wave can integrate stimulus energy over several seconds. For every light intensity there is a critical duration beyond which integration no longer takes place. If the c-wave is to be used as a clinical measure of pigment epithelial function, the techniques for human recording must be improved, and recording protocols must be devised which selectively emphasize the pigment epithelial components of the response.
KeywordsRetina Ketamine Pentobarbital Urethane Zinn
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