An Open-source Static Threshold Perimetry Test Using Remote Eye-tracking (Eyecatcher): Description, Validation, and Preliminary Normative Data

Purpose: To describe, validate, and provide preliminary normative data for an open-source eye-movement perimeter (Eyecatcher). Methods: Visual field testing was performed monocularly in 64 normally sighted young adults, using (i) a Humphrey Field Analyzer (HFA) and (ii) the novel Eyecatcher procedure. Eyecatcher used a remote eye-tracker to position stimuli relative to the current point of fixation, and observers responded by looking towards the stimulus. In both tests, Goldman III stimuli were sampled from a 24-2 grid, and were presented against a 10 cd/m(2) background. Participants completed each test twice to assess test-retest repeatability. Results: Mean Sensitivity (MS) did not differ between Eyecatcher and the HFA (P = 0.086), and both tests exhibited similar test-retest repeatability (CoREyecatcher = +/- 1.86 dB; CoRHFA = +/- 1.95 dB). Eyecatcher was also able to detect changes in sensitivity across the normal visual field (the "Hill of Vision"), and could differentiate the physiological blind spot from adjacent retinal locations. Mean sensitivities and 95% limits of agreement are described for each pointwise location. Conclusions: Eyecatcher can use eye movements to assess visual fields in young, normally sighted adults. In such observers, it provides results similar to the current gold standard clinical device (HFA). Translational Relevance: Given further development, eye movement perimeters such as Eyecatcher could be particularly useful for individuals unable to perform traditional perimetric assessments, such as young children or stroke patients. Full technical details and information on how to freely acquire the source code are included.