Comparison between Fundus Automated Perimetry and Humphrey Field Analyzer: performance and usability of the Fundus Automated Perimetry and Humphrey Field Analyzer in healthy, ocular hypertensive, and glaucomatous patients

Purpose: We compared the performance and usability of the Fundus Automated Perimetry (FAP) and Humphrey Field Analyzer (HFA) in patients with glaucoma, ocular hypertension, and healthy subjects. Materials and methods: A total of 60 participants, divided in three groups of 20, glaucoma (POAG), ocular hypertension (OHT), and controls group, underwent a HFA test 24-2 SITA standard and a FAP test 24-2 ZEST sequence, in randomized order. The mean differences between perimeters of mean deviation (MD), pattern standard deviation (PSD) were correlated using the t-test and the Bland-Altman plot while execution time, Glaucoma Staging System 2 (GSS2), Hodapp-Parrish-Anderson staging system, localization of the defect, false positives (FP), and false negatives (FN) were compared with t-test analysis. Usability was measured through answers of a dedicated questionnaire. Results: MD's difference was higher for FAP than HFA: OHT -2.20 ± 1.33 dB (p < 0.001), POAG -2.00 ± 1.66 dB (p < 0.001), and controls -1.08 ± 1.43 dB (p < 0.001). PSD's difference was higher for FAP than HFA: OHT 0.85 ± 1.16 dB (p < 0.001), POAG 0.78 ± 2.32 dB (p = 0.043), and controls 0.49 ± 1.15 dB (p < 0.001). GSS2's difference showed that FAP found more severe defects than HFA. Exams duration was longer for FAP versus HFA: in OHT 363 s versus 301 s, in POAG 494 s versus 362 s, and in controls 360 s versus 277 s. For FN and FP, there were no statistically significant differences. The 77% of all subjects preferred FAP to HFA test. Conclusion: Considering MD and GSS2 classification, FAP finds more severe defects. Moreover, although FAP duration is longer, this method is preferred by most of the patients.