Abstract
Purpose :
Swedish Interactive Threshold Algorithm (SITA)-Standard (SS) and SITA-Fast (SF) are widely utilized standard automated perimetry(SAP) strategies used in glaucoma management. In this retrospective comparative study, we aimed to compare several parameters of visual field testing between SS and SF strategies.
Methods :
We reviewed all 24-2 SS and SF visual field tests (Humphrey® Field Analyzer; Carl Zeiss Meditec) of glaucoma and glaucoma suspect eyes performed between Jan. 2013 and Aug. 2016 at the Kresge Eye Institute. We only included the better eye of each patient based on mean deviation. To reduce the learning effect, we only included the third visual field test of each eye. Other criteria included: age >30 years, best corrected visual acuity > 20/100, spherical equivalent > -8 diopters, and astigmatism > 3 diopters at the time of visual field testing. Eyes with neurological and major retinal diseases were excluded. The study outcomes included: test duration, mean deviation, pattern standard deviation, visual field index, fixation loss, false positive and false negative errors. To define the number of reliable tests in each group, we used the reliability cut off points defined by the manufacturer(FL< 20%, FP <15% and FP <15%). There were no selection criteria for choosing patients to do SS or SF tests. Selection was completely based on practice pattern of the glaucoma specialists at our institution.
Results :
468 SS and 472 SF visual field tests were included in this study. Table 1 compares different study outcomes between the two study groups. SS strategy showed significantly longer test duration (p<0.001) and worse fixation loss (p=0.013)(Table 1). SF strategy showed significantly more reliable visual field tests compared to SS strategy(51.27% vs. 42.09%; p= 0.041)(Table 2). Logistic regression analysis revealed test duration and SF strategy had significant negative (coefficient: -0.438; p < 0.001) and positive (odds ratio: 1.31; p <0.001) association with visual field test reliability, respectively(Table 2).
Conclusions :
SF strategy showed shorter test duration, better fixation loss and more reliable visual field tests. False positive and negative errors were comparable between two strategies. Logistic model showed test duration and SF strategy are significantly associated with test reliability. Severity of glaucoma indicated by MD, PSD and VFI was not associated with test reliability.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.