Dataset Information

Electrophysiological measures of dysfunction in early-stage diabetic retinopathy: No correlation between cone phototransduction and oscillatory potential abnormalities.

ABSTRACT:

Purpose

To define the relationship between abnormalities in the activation phase of cone phototransduction and the oscillatory potentials (OPs) of the light-adapted electroretinogram in diabetics who have mild or no retinopathy.

Methods

Subjects included 20 non-diabetic controls and 40 type-2 diabetics (20 had no clinically apparent diabetic retinopathy [NDR] and 20 had mild nonproliferative DR). Single flash responses for a series of stimulus retinal illuminances were measured under light-adapted conditions using conventional techniques. The a-waves of the responses were fit with a delayed Gaussian model to derive R_mp3 (maximum amplitude of the massed photoreceptor response) and S (phototransduction sensitivity). OPs were extracted from the responses by conventional band-pass filtering.

Results

Analysis of variance (ANVOA) indicated that both diabetic groups had significant OP amplitude and S reductions compared to the controls, whereas R_mp3 did not differ significantly among the groups. Although log OP amplitude and log R_mp3 were significantly correlated for the control subjects for each flash retinal illuminance (all r?>?0.49, p?mp3 were not correlated for either diabetic group for any flash retinal illuminance (all r???0.36, p???0.13). Log OP amplitude and log S were generally not correlated significantly for the control or diabetic groups.

Conclusion

OP amplitude losses do not appear to be related to reduced cone sensitivity in early-stage diabetic retinopathy. This suggests that diabetes may separately affect cone function, as evidenced by cone phototransduction sensitivity losses, and inner-retina function, as evidenced by OP amplitude losses.

SUBMITTER: McAnany JJ

PROVIDER: S-EPMC6980927 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Publications

Electrophysiological measures of dysfunction in early-stage diabetic retinopathy: No correlation between cone phototransduction and oscillatory potential abnormalities.

McAnany J Jason JJ Liu Karen K Park Jason C JC

Documenta ophthalmologica. Advances in ophthalmology 20190911 1

<h4>Purpose</h4>To define the relationship between abnormalities in the activation phase of cone phototransduction and the oscillatory potentials (OPs) of the light-adapted electroretinogram in diabetics who have mild or no retinopathy.<h4>Methods</h4>Subjects included 20 non-diabetic controls and 40 type-2 diabetics (20 had no clinically apparent diabetic retinopathy [NDR] and 20 had mild nonproliferative DR). Single flash responses for a series of stimulus retinal illuminances were measured un ...[more]

PMID: 31512016

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Dataset Information

Electrophysiological measures of dysfunction in early-stage diabetic retinopathy: No correlation between cone phototransduction and oscillatory potential abnormalities.

Purpose

Methods

Results

Conclusion

Publications

Electrophysiological measures of dysfunction in early-stage diabetic retinopathy: No correlation between cone phototransduction and oscillatory potential abnormalities.

Similar Datasets

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