Microperimetric test-retest repeatability at the border of a deep scotoma was worse than at other areas of normal retina, and this highlights the limitation of applying a single estimate of test-retest repeatability to determine whether significant functional decline has occurred at the border of a deep scotoma.

Purpose: We compared measurements of central retinal sensitivity on a portable, lowcost tablet device to the established method of microperimetry in age-related macular degeneration (AMD).Methods: A customized test designed to measure central retinal sensitivity (within the central 18 radius) on a tablet device was developed using an open-source platform called PsyPad. A total of 30 participants with AMD were included in this study, and all participants performed a practice test on PsyPad, followed by four tests of one eye and one test of the other eye. Participants then underwent standardized microperimetry examinations in both eyes. Results:The average test duration on PsyPad was 53.9 6 7.5 seconds, and no significant learning effect was observed over the examinations performed (P ¼ 1.000). The coefficient of repeatability of central retinal sensitivity between the first two examinations on PsyPad was 61.76 dB. The mean central retinal sensitivity was not significantly different between PsyPad (25.7 6 0.4 dB) and microperimetry (26.1 6 0.4 dB, P ¼ 0.094), and the 95% limits of agreement between the two measures were between À4.12 and 4.92 dB. Conclusions:The measurements of central retinal sensitivity can be performed effectively using a tablet device, displaying reasonably good agreement with those obtained using the established method of microperimetry.Translational Relevance: These findings highlight the potential of tablet devices as low-cost and portable tools for developing and performing visual function measures that can be easily and widely implemented.