Glaucoma home-monitoring using a tablet-based visual field test (Eyecatcher): An assessment of accuracy and adherence over six months

Jones, P. R.; Campbell, P.; Callaghan, T.; Jones, L.; Asfaw, D. S.; Edgar, D. F.; Crabb, D. P.

Purpose: To assess accuracy and adherence of visual field (VF) home-monitoring in a pilot sample of glaucoma patients. Design: Prospective longitudinal observation. Methods: Twenty adults (median 71 years) with an established diagnosis of glaucoma were issued a tablet-perimeter (Eyecatcher), and were asked to perform one VF home-assessment per eye, per month, for 6 months (12 tests total). Before and after home-monitoring, two VF assessments were performed in-clinic using Standard Automated Perimetry (SAP; 4 tests total, per eye). Results: All 20 participants could perform monthly home-monitoring, though one participant stopped after 4 months (Adherence: 98%). There was good concordance between VFs measured at home and in the clinic (r = 0.94, P < 0.001). In 21 of 236 tests (9%) Mean Deviation deviated by more than {+/-}3 dB from the median. Many of these anomalous tests could be identified by applying machine learning techniques to recordings from the tablets' front-facing camera (Area Under the ROC Curve = 0.78). Adding home-monitoring data to 2 SAP tests made 6 months apart reduced measurement error (between-test measurement variability) in 97% of eyes, with mean absolute error more than halving in 90% of eyes. Median test duration was 4.5 mins (Quartiles: 3.9 - 5.2 mins). Substantial variations in ambient illumination had no observable effect on VF measurements (r = 0.07, P = 0.320). Conclusions: Home-monitoring of VFs is viable for some patients, and may provide clinically useful data.