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Purpose: To evaluate acuity and multifocal electroretinogram (mfERG) responses from the macula in affected and unaffected fellow eyes of patients with macular holes. Methods: We tested 10 eyes with macular hole and 10 fellow eyes from 11 patients. We measured local visual acuity thresholds at 27 discrete locations within 21° diameter using the Functional Fundus Imaging System (FFIS), a psychophysical system that measures visual acuity as a function of visual field location, and local ERG responses within 45° diameter using the mfERG. Results: In the affected eyes, the mean FFIS visual acuity thresholds were significantly elevated within the central 21° diameter area, compared to a group of control eyes. No significant differences were found between the acuities of the fellow eyes compared to those of the control group. The amplitudes of the first positive peak of the mfERG were reduced in the central 7.8° in affected eyes. In the central 2°, 4 out of 10 affected eyes showed non-measurable ERG signals. The remaining six eyes showed significantly reduced mean amplitudes, but not delayed implicit times, when compared to the control group. For the fellow eyes, the mean amplitudes of the mfERG and implicit times did not differ from the means of the control eyes. Conclusions: Both local psychophysical and electrophysiological testing demonstrated retinal dysfunction extending beyond the site of the macular holes in some patients (three of the patients had central mfERG amplitudes falling within the normal range). [ABSTRACT FROM AUTHOR]

Abstract We examined the reliability of Humphrey visual field thresholds and multifocal electroretinogram (mfERG) amplitudes and timing in a group of patients with Retinitis Pigmentosa (RP). Eight patients with RP and seven control subjects were tested five times: at baseline (visit #0), at three weekly follow-up visits (visits #1#3), and at three months (visit #4). For the Humphrey thresholds, differences between dB values on repeat visits were obtained. Differences between log values on repeat visits were calculated for mfERG amplitude and implicit time. We used the standard deviations of these difference scores as a measure of reliability and the means of the difference scores as a measure of progression. We found that the majority of the patients repeat data were more variable than that of the control subjects for both the Humphrey and mfERG. We found no single factor that predicted the magnitude, or the variance, of the SD of differences scores for the patients. We recommend that each patients reliability be assessed individually. Ultimately, the choice of an outcome measure must be guided by its reliability, as well as its ability to assess the visual function of interest. [ABSTRACT FROM AUTHOR]

The author discusses several papers presented at the 46th Symposium of the International Society for Clinical Electrophysiology of Vision (ISCEV), held in Morgantown, West Virginia on July 10-15, 2008. The topics include link between the structure and function of cortex and retina, role of electrophysiology in identifying low vision. William W. Dawson lectured on his research on naturally occurring age-related macular degeneration in monkeys. Information on oral presentations are also presented.