Utility of 10-2 Visual Field Testing in Glaucoma Patients with Early 24-2 Visual Field Loss

Abstract Objective To determine whether the 10-2 test of the Humphrey Field Analyzer detected a higher proportion of abnormal visual fields compared to the 24-2 test in the central 10° in patients with early visual field damage. Design Prospective observational study. Participants Patients with early open-angle glaucoma and healthy controls. Methods All subjects underwent a 24-2 and 10-2 test. Only the 12 central test locations of the 24-2 test were included to analyse equivalent visual field areas. The performance of the two tests was compared across 4 pointwise criteria: total deviation (TD) and pattern (PD) deviation analyses at the 5% and 2% levels. Analyses were also conducted for two pairs of follow-up tests, each performed 4 months apart. Main Outcome Measures (i) area under the receiver operating characteristics curve (AUC); (ii) sensitivity at identically matched specificity for the 4 criteria; (iii) overlap (whole field and by quadrant) of abnormal visual fields with both tests; (iv) repeatability of the findings over two follow-up tests. Results One eye each of 97 patients with early glaucoma (median mean deviation, -2.31 dB) and 65 controls were included in the study. The AUCs for the 24-2 and 10-2 were not significantly different for any of the 4 criteria and ranged from 0.88 to 0.93 and 0.91 to 0.94, respectively. At matched specificity, the sensitivity of the 24-2 was significantly higher for all criteria except for PD analysis at 5%. In patients with an abnormal field with either test, the overlap varied from 60% to 86% depending on the criterion, while analysis according to quadrant yielded a concordance ranging from 70% to 87%. Over the follow-up, the repeatability of the test result (both 24-2 and 10-2 abnormal, either abnormal, or both normal) was achieved in 55% to 70% of patients. Conclusions In this study of glaucoma patients with early damage with the 24-2 test, there was little evidence that adding the 10-2 test revealed additional undetected defects in the central visual field. It might be more prudent to reserve 10-2 testing for following selected patients with a higher risk of progression in the central visual field.