Spatial and Temporal Frequency Tuning Of Pattern-Reversal Retinal Potentials (PRRPs)

Bloom and Sokol, Feb. 1977; Armington, Corwin, and Marsetta, Nov. 1971; and Maffei and Fiorentini, Feb. 1981; have described in detail electroretinographic responses evoked by spatially oscillating checkerboard patterns. Maffei and Fiorentini proposed that this pattern-reversal ERG may provide a new diagnostic tool for early detection of diseases specific to the ganglion cells and optic nerve. Evidence obtained from sectioning the optic nerves of cats suggests that the electrical response observed from patterned stimuli arises primarily from the ganglion cells of the retina. Diffuse Flash Electroretinograms, presently used in electrodiagnostic evaluation of retinal pathology have their primary etiology in the photoreceptor and the inner nuclear layers of the sensory retina. These tests are not effective in diagnosing pathology arising in subsequent layers of the visual pathway. Although VER's may be of diagnostic value for optic nerve and cortical evaluation, no present electrodiagnostic test can explicitly evaluate ganglion cell defects. It is the intention of this project to examine pattern-reversal retinal potentials to obtain normative clinical data using different temporal and spatial frequency patterns to determine appropriate parameters to obtain the most reliable responses. Subsequent application of this data to patients with optic nerve disease will also be examined.