Development and Validation of an Internet-Based Remote Perimeter (Perimouse).

Abstract

We sought to validate the feasibility of Perimouse, an internet-based remote perimeter that allows for natural fixation and can be performed on most computers via a web page. In this cross-sectional study, Perimouse evaluated the visual field of 45 healthy people and 27 patients with primary open-angle glaucoma on a laptop. Participants used a mouse cursor to locate new dots on the screen that were determined by preset saccade vectors. A "click and confirm" strategy was used to eliminate the unwanted visual search. Dot brightness was either fixed at 12dB in the suprathreshold program (screening program) or variable in the threshold program. We compared Perimouse outcomes with the Humphrey Field Analyzer (HFA) 24-2 Swedish Interactive Testing Algorithm standard program. In the screening program, Perimouse showed moderate to high concordance with HFA. The intraclass coefficient ranged from 0.58 to 0.86 in different areas of Garway-Heath mapping. In the threshold program, normal subjects had threshold ranging from 19 to 16dB, presenting sensitivity changes according to the "hill of vision". The test-retest difference was 0.09dB. Habitual spectacle correction and environmental luminance (2-337 lux) had little impact on the central or peripheral threshold (P > 0.05). The correlation between Perimouse and HFA threshold sensitivity was strong (R = 0.950), although Perimouse mean defect was 4.40dB higher than the HFA mean defect. Perimouse is a reliable visual field test that correlates strongly with HFA. It shows potential for population screening and monitoring visual field defects. Perimouse assesses the visual field using saccade vectors without eye trackers, enhancing its accessibility via a web page.