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Local cone and rod system function in patients with retinitis pigmentosa
K Holopigian1, W Seiple, V C Greenstein
1Department of Ophthalmology, New York University School of Medicine, BEL 5N15, 550 First Avenue, New York, NY 10016, USA. kh19@nyu.edu
Investigative Ophthalmology & Visual Science
|February 27, 2001
Summary
In retinitis pigmentosa (RP), cone system function showed better agreement between psychophysical and electrophysiological tests than rod system function. Psychophysical measures better corresponded to each other than electrophysiological measures for both systems.
Area of Science:
- Ophthalmology
- Neuroscience
- Vision Science
Background:
- Retinitis pigmentosa (RP) is a group of inherited retinal diseases causing progressive vision loss.
- Understanding the functional deficits of cone and rod photoreceptor systems is crucial for RP management.
Purpose of the Study:
- To compare local cone and rod system function in RP patients.
- To evaluate electrophysiological and psychophysical techniques for assessing cone and rod function.
Main Methods:
- Cone-mediated multifocal electroretinograms (M-ERGs) and visual fields were assessed.
- Rod-mediated M-ERGs and visual fields were also measured.
- Seven patients with RP participated in the study.
Main Results:
- Cone system visual fields and M-ERG implicit times were normal centrally but abnormal peripherally.
- Rod-mediated M-ERGs were often measurable and within normal limits, but showed no correlation with visual field thresholds.
- Psychophysical thresholds for both cone and rod systems showed regional correspondence.
Conclusions:
- Local correspondence between psychophysical and electrophysiological measures was better for the cone system than the rod system in RP.
- Psychophysical measures demonstrated better correspondence than electrophysiological measures for both cone and rod function.
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