Visual Field Progression Rates in Glaucoma: Frontloaded Versus Clinical Standard (Nonfrontloaded) SITA-Faster.

Purpose

To compare glaucoma progression detection rates using mean deviation (MD) slopes when using frontloaded (2 visual field [VF] tests per eye per visit) and clinical standard (1 VF test per eye per visit) 24-2 SITA-Faster test protocols in a clinical practice.

Design

Prospective accuracy analysis comparing assessment methods.

Subjects

6571 reliable VF tests of 336 subjects.

Methods

Mean deviation (MD) slopes were calculated for each eye for each participant over time, with significant slopes (P < .05) defining progression. The number of progressors were compared between frontloaded and clinical standard approaches using the McNemar test. Time and visit to detection and progression rates were compared for mutually detected cases using Wilcoxon rank-sum tests.

Main outcome measure: Cases of progression detected, time and visit to detection, and progression rates.

Results

The average baseline MD values were -1.94 dB and -1.78 dB for right and left eyes, respectively. Over approximately 2.7-2.8 years of follow-up and 6.2-6.4 visits, there were 25 and 33 unique cases of progression detected for right and left eyes, respectively. Frontloading detected more than 2.3 times more progressors compared with the clinical standard. When considering mutually detected cases, frontloading resulted in an average of 0.5 years' earlier detection compared to the clinical standard (P = .0087). For those who progressed, there was no significant difference in the progression rate measured using either method (P > .05).

Conclusions

Frontloaded (two 24-2 SITA-Faster VF tests per eye per visit) tests detected more than twice the number of glaucoma progressors based on MD slopes in a cohort of patients with predominantly early glaucoma, compared with the clinical standard (1 VF per eye per visit). These results provide, for the first time, empirical evidence supporting frontloaded VF testing to detect more cases of glaucoma progression at an earlier time point, thereby allowing earlier intervention to minimize vision loss.