Open AccessPartial Masking of the Canine Electroretinogram by Oscillatory Potentials
Author(s) -
Sims Michael H.
Publication year - 1990
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/j.1939-1676.1990.tb00872.x
Subject(s) - erg , notching , bandwidth (computing) , electroretinography , amplifier , medicine , optics , amplitude , retinal , physics , ophthalmology , telecommunications , computer science , materials science , metallurgy
Recording the electroretinogram (ERG) in dogs has become a standard procedure in clinical ophthalmology. The ERG provides highly objective information about retinal function that is otherwise unobtainable from dogs. However, problems may be encountered in measuring the latencies and amplitudes of the a and b waves, depending upon the amplifier bandwidth used to record the potential. Superimposed on the canine ERG are other complex retinal potentials, some of which have higher frequency spectra than those that give rise to a and b waves. Whereas an amplifier bandwidth of 1.0 to 100 Hz or more insures that the slower components of the ERG are recorded, it also allows higher frequency oscillatory potentials (OP) to be recorded on the b wave. The OP cause a notching in the peak of the b wave thus necessitating a decision about how to measure the b wave. Bandwidth characteristics of the ERG and OP are presented and some possible methods for measuring the OP‐contaminated ERG are discussed. (Journal of Veterinary Internal Medicine 1990; 4:40–42)