Comparison of the Performance of a Novel, Smartphone-based, Head-mounted Perimeter (GearVision) with the Humphrey Field Analyser.

Pradhan, Zia Sultan; Sircar, Tushar; Agrawal, Harshit; Rao, Harsha Laxmana; Bopardikar, Ajit; Devi, Sathi; Tiwari, Vijay N

PRECIS The agreement between a head-mounted perimeter (GearVision) and HFA for total threshold sensitivity was a mean difference of -1.9â–’dB (95% limits of agreement -5 to 1). GearVision was the preferred perimeter in 68.2% of participants. PURPOSE To compare reliability indices and threshold sensitivities obtained using a novel, smartphone-based, head-mounted perimeter (GearVision) with the Humphrey field analyser (HFA) in normal, glaucoma suspect and glaucoma patients. A secondary objective was to evaluate the subjective experience participants had with both perimeters using a questionnaire. METHODS In a prospective, cross-sectional study, 107 eyes (34 glaucoma, 18 glaucoma suspect, and 55 normal) of 54 participants underwent HFA and GearVision in random order. The main outcome measure was the agreement of threshold sensitivities using Bland and Altman analysis. Participants also completed a questionnaire about their experience with the devices. RESULTS Median false positive response rate for GearVision was 7% (4-12) while for HFA it was 0% (0-6, P<0.001). Median false negative response rate was similar for both tests. 84 eyes with reliable HFA and GearVision results were included in the final analysis. Median threshold sensitivity of all 52 points on HFA was 29.1â–’dB (26.5, 30.7) and for GearVision was 30.6â–’dB (29.1, 32.6; P<0.001). Mean difference (95% limits of agreement, LoA) in total threshold sensitivity between HFA and GearVision was -1.9â–’dB (-5, 1). The 95% LoA were fairly narrow (-8 to 2â–’dB) across the 6 Garway-Heath sectors. Most participants preferred to perform GearVision (68.2%) if required to repeat perimetry compared to HFA (20.6%, P<0.001). CONCLUSIONS There was fairly good agreement between the threshold sensitives of GearVision and HFA. GearVision was also preferred by most patients and could potentially supplement HFA as a portable or home perimeter.