Dataset Information

Edge of Scotoma Sensitivity as a Microperimetry Clinical Trial End Point in USH2A Retinopathy.

ABSTRACT: Purpose:Microperimetry is commonly used to assess retinal function. We perform cross-sectional and longitudinal analysis on microperimetry parameters in USH2A retinopathy and explore end points suitable for future clinical trials. Methods:Microperimetry was performed using two grids, Grid 1 (18° diameter) and Grid 2 (6° diameter). In Grid 1, four parameters (number of nonscotomatous loci, mean sensitivity [MS], responding point sensitivity [RPS], and edge of scotoma sensitivity [ESS]) were analyzed. In Grid 2, number of nonscotomatous loci and MS were examined. Interocular symmetry was also examined. Longitudinal analysis was conducted in a subset of eyes. Results:Microperimetry could be performed in 16 of 21 patients. In Grid 1 (n = 15; average age, 35.6 years), average number of nonscotomatous loci, MS, RPS, and ESS were 46.6 loci, 10.0 dB, 14.7 and 9.6 dB, respectively. In Grid 2 (n = 13; average age, 37.4 years), 12 eyes had measurable sensitivity across the entire grid. Average MS was 23.8 dB. Interocular analysis revealed large 95% confidence intervals for all parameters. Longitudinally, Grid 1 (n = 12, average follow-up 2.6 years) ESS showed the fastest rate of decline (-1.84 dB/y) compared with MS (-0.34 dB/y) and RPS (-0.90 dB/y). Conclusions:Our data suggest that ESS may be more useful than MS and RPS in test grids that cover a large extent of the macula. We caution the use of contralateral eye as an internal control. Translational Relevance:ESS may decrease the duration or sample size of treatment trials in USH2A retinopathy.

SUBMITTER: Charng J

PROVIDER: S-EPMC7488629 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Edge of Scotoma Sensitivity as a Microperimetry Clinical Trial End Point in <i>USH2A</i> Retinopathy.

Charng Jason J Lamey Tina M TM Thompson Jennifer A JA McLaren Terri L TL Attia Mary S MS McAllister Ian L IL Constable Ian J IJ Mackey David A DA De Roach John N JN Chen Fred K FK

Translational vision science & technology 20200909 10

<h4>Purpose</h4>Microperimetry is commonly used to assess retinal function. We perform cross-sectional and longitudinal analysis on microperimetry parameters in <i>USH2A</i> retinopathy and explore end points suitable for future clinical trials.<h4>Methods</h4>Microperimetry was performed using two grids, Grid 1 (18° diameter) and Grid 2 (6° diameter). In Grid 1, four parameters (number of nonscotomatous loci, mean sensitivity [MS], responding point sensitivity [RPS], and edge of scotoma sensiti ...[more]

PMID: 32974081

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Dataset Information

Edge of Scotoma Sensitivity as a Microperimetry Clinical Trial End Point in USH2A Retinopathy.

Publications

Edge of Scotoma Sensitivity as a Microperimetry Clinical Trial End Point in <i>USH2A</i> Retinopathy.

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