Electroretinogram studies

Parisi, V., M. Tedeschi et al. (2008). Carotenoids and antioxidants in age-related maculopathy Italian study Multifocal electroretinogram modifications after 1 year. Ophthalmology 115(2) 324—333. 

Another indirect measure of physiological function relating to PUFA metabolism comes from studies of the electroretinogram (ERG). It is known that adequate n-3 PUFA levels are essential for normal retinal function. Our group has shown that schizophrenic patients show ERG changes similar to those that occur in states of experimental dietary deprivation of n-3 in primates (Warner et al., 1999). 

One test, the electroretinogram (ERG), was not accomplished during the typical data collection week. The ERG, a method of measuring retinal function, was administered to a subset of enrollees during the week prior to the normal data collection period. Studies in animals chronically-exposed to JP8 have shown selective cellular damage to cells located in the retina and cerebellum. Since any retinal changes detectable by the ERG would be the result of chronic exposure, repeat ERG testing (pre and post work period) was unnecessary. Approximately 20 subjects at each base were selected to complete the ERG. 

Electroretinogram (ERG) The ERG is a device designed to measure the electrical response of the eye to brief, high intensity flashes. In this study, the ERG was used to determine the association between JP8 exposure and retinal Mueller cell function. Subjects who volunteered for this protocol underwent an ERG as part of their evaluation. Since the hypothesized retinal changes are associated with chronic JP8 exposure, the ERG procedure was accomplished only once on the enrollee selected. In addition to comparisons between the exposed and unexposed groups, ERG results were compared with normative data. 

However, L supplementation at achievable dietary levels increased and maintained serum levels, and this was associated with an improvement in glare recovery and VA [177]. A pilot study found that short-term intervention including 15 mg lutein was associated with statistically significant changes in macular focal electroretinogram parameters, suggestive of an improvement in retinal function in ARM [178]. 

A subsequent study was performed in order to compare the influence of different types of anesthetics on two of the main electroretinogram waves in the beagle dog and showed good homogeneity of values for each kind of anesthetic and a trend to variable increases in latencies depending on the anesthetic. It was found that results could be easily obtained in conscious dogs. 

The electroretinogram (ERG) is composed of responses of many different retinal cell types. Many studies have been made to separate the ERG into components and to link different components to different retinal structures. In theese studies, authors used microelectrodes and intact eyes of laboratory animals (Heynen and van Norren, 1985). However, in most clinical situations or during the course of toxicity studies, this technic is not suitable because it does not allow long-term studies on the same animal. Our first goal was to find a technic that permit to record global ERGs from the same animal at different times. 

In the present study, we examined ocular toxicity of ofloxacin ophthalmic solution (3 times daily for one year application) in beagle dogs with pigmented eyes. In order to investigate the effects of melanin-bound ofloxacin on retinal function and the effect of ofloxacin on central nerve system, electroretinogram (ERG) was recorded and behavior of dogs was observed during test periods. 

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