Standard Reliability and Gaze Tracking Metrics in Glaucoma and Glaucoma Suspects.

PURPOSE

To compare standard reliability metrics and gaze tracking (GT) metrics on the Humphrey field analyzer (HFA).

DESIGN

Retrospective cross-sectional study.

METHODS

The study was performed at the VA Medical Center, San Diego, and included 494 glaucoma and glaucoma suspect patients who had an HFA 24-2 SITA Fast visual field (VF) performed in both eyes. Standard reliability metrics (fixation loss [FL], false-positive [FP], and false-negative [FN]) were compared to GT metrics (deviations of 1°-2° [M1], deviations of 3°-5° [M3], deviations >6° [M6], and tracking failure frequency [TFF]). The main outcome measures were Spearman rank-based correlation coefficient and area under the receiver operating characteristic (AUROC) curves between standard and GT reliability metrics.

RESULTS

The 95th percentile limits for GT metrics were 66.7% for M1, 67.5% for M3, 49.5% for M6, and 79.8% for TFF. There were statistically significant correlations between standard and GT reliability metrics using the 95th percentile as a binary cutoff for GT metrics. However, low Spearman correlation values and AUROC calculations suggest little clinical significance of the associations. FN increased as VF severity worsened (P < .001). M6 was lower in eyes with mild compared to moderate and advanced VF loss (P = .012).

CONCLUSIONS

GT metrics do not have a clinically significant association with standard reliability metrics. Both FN and M6 are influenced by VF severity. Aggregate GT metrics do not aid in reliability assessment. These findings suggest that GT metrics may provide an alternative or complementary measure of VF reliability.