ABSTRACT
PURPOSE: We determine the feasibility of using a home-based tablet device to monitor retinal sensitivity (RS) in intermediate age-related macular degeneration (iAMD), the benefits of weekly reminders, and the comparison with clinic-based results. METHODS: A customized test for tablets was designed to measure RS (within central 2°) in individuals with iAMD at weekly intervals in their home, with remote data collection. Half of the participants were randomized to receive weekly test reminders. Clinic-based microperimetric macular sensitivity results were compared to tablet results. Participation rates were analyzed at 2 months. RESULTS: Of 38 participants (mean age, 70.3 years) with iAMD enrolled in the study, 21 (55%) were using the tablet-based test at 2 months. Common reasons for inactivity were noncompatible devices (41.1%) or other technology access issues (35.3%). Participants with weekly reminders completed tests more regularly (6.6 ± 3.9 vs. 8.7 ± 4.1 days, P = 0.01), but weekly reminders showed no effect on participation rates (P = 0.69). Mean RS from the tablet device (25.03 ± 2.41 dB) was not significantly different from the clinic-based microperimetry performance (25.21 ± 2.20 dB; P = 0.58). CONCLUSIONS: Regular monitoring of retinal function on a tablet device in a home setting in individuals with iAMD is feasible with results comparable to those of clinic-based microperimetry. Weekly reminders resulted in more frequent testing. Seamless ability to access technology will be important for higher participation rates. TRANSLATIONAL RELEVANCE: The use of home-monitoring on a tablet-device is promising, but adequate support for an older cohort to take up technology is required if such a tool is to be useful for long-term home monitoring.
ABSTRACT
PURPOSE: To determine the feasibility of a tablet-based application to detect changes in retinal sensitivity and correlations with underlying pathology in neovascular age-related macular degeneration (nAMD) eyes undergoing treatment and in at-risk fellow eyes. METHOD: Participants with nAMD in at least one eye were recruited, examined, and imaged using spectral-domain optical coherence tomography (SD-OCT). Retinal sensitivity was measured within the central 5° at 12 locations using a customized test delivered on an iPad. Test points were superimposed on SD-OCT locations to investigate structure/function relationships. RESULTS: Included in the study were 53 nAMD eyes and 21 at-risk fellow eyes. In nAMD eyes, the mean retinal sensitivity was 24.1 ± 1.8 dB with reduced retinal sensitivity associated with the presence of atrophy (P < 0.01), retinal pigment epithelium (RPE) disruption (P < 0.01), and absent ellipsoid zone (EZ) (P < 0.01), but not with the presence of subretinal fluid (P = 0.94) nor intraretinal fluid (P = 0.52). In at-risk eyes, the average retinal sensitivity was 28.8 ± 0.6 dB, with reduced sensitivity significantly associated with the presence of drusen, atrophy, RPE disruption, and absent EZ (P < 0.01). CONCLUSION: The tablet-based test of retinal sensitivity was able to be performed by an elderly cohort with nAMD. The ability to correlate differences in sensitivity with pathology is encouraging when considering using the tablet devices as a home monitoring tool with remote surveillance. Dual pathology often present with retinal fluid confounded our ability to correlate fluid with sensitivity. TRANSLATIONAL RELEVANCE: These findings highlight the potential of tablet-based devices in performing visual function measures as a home monitoring tool with remote surveillance for the earlier detection of nAMD.
ABSTRACT
PURPOSE: We compared measurements of central retinal sensitivity on a portable, low-cost 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 1° 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 ± 7.5 seconds, and no significant learning effect was observed over the examinations performed (P = 1.000). The coefficient of repeatability of central retinal sensitivity between the first two examinations on PsyPad was ±1.76 dB. The mean central retinal sensitivity was not significantly different between PsyPad (25.7 ± 0.4 dB) and microperimetry (26.1 ± 0.4 dB, P = 0.094), and the 95% limits of agreement between the two measures were between -4.12 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.
ABSTRACT
This article introduces PsyPad, a customizable, open-source platform for configuring and conducting visual psychophysics experiments on iPads without the need for any code development for the iPad. Stimuli for experiments are created off-line as a library of images. The PsyPad app (obtainable from the Apple App Store) presents the images according to either built-in, customizable staircase or method of constant stimuli procedures, mapping stimuli levels to images based on the image file names. On-screen buttons for responses are configurable and matched to "correct" using the image file name of any given stimulus. All actions are logged into a text file and sent to a specified server at the end of the test if an Internet connection is available. If the iPad is not connected, the results are uploaded the next time the iPad is online. We provide a secure server for this purpose, but the server-side software is also open source if researchers choose to run their own server.
