SITA-Faster Test Provides Repeatable Glaucoma Defect Analysis When Front Loaded

Swedish Interactive Threshold Algorithm (SITA) Faster testing can provide repeatable data that may yield added confidence in discerning new deficits, or reversal of prior defects, in patients with glaucoma, according to research published in Ophthalmology. The study shows that, in suspected or confirmed glaucoma, 2 clustered, same-visit visual field (VF) assessments per eye with SITA-Faster protocol produced reliable metrics in approximately the same time needed for 1 SITA-Standard.

The research took into account 144 eyes of 91 patients (mean age 68.6 [SD 13.4] years) at an academic hospital ophthalmology department in Australia. Early, moderate, or advanced glaucoma was confirmed in 79.2% of participants.

A prior SITA-Standard test revealed the group’s mean deviation (MD) was -5.83 dB, and VF index (VFI) 85.6%. In the initial 52-test-location SITA-Faster test, MD was -5.28 dB and VFI 87.1%, and the second yielded -5.71 dB, VFI 86.2%. Repeated measures ANOVA indicated no significant difference among the 3 evaluations (P =.48).

Clustered SITA-Faster tests revealed repeatable data that agreed with SITA-Standard for 62.3% of points in the deviation grid, reversal of defect in 8.2% of locations, and new defects in 5.4%. No significant difference was detected in nonrepeatable locations for how defects were spread out, peripherally or centrally. Also, the researchers found similar rates among Standard or Faster algorithms for producing 1 or more reliable test map per participant (P =.77).

Duration differed; 379 seconds for SITA-Standard, 160 seconds for the first SITA-Faster assessment, and 158 seconds in the subsequent SITA-Faster (P <.0001).

“Furthermore, the repeatable pointwise data demonstrated that 20.1% of eyes in our cohort fulfilled Anderson and Patella’s criteria of a new visual field defect comprising 3 contiguous points including one with P <0.01 on two field tests,” according to the researchers. They also report “no observable decline in performance from test fatigue” using 2 SITA-Faster assessments.

Previous studies involving SITA-Standard report slightly higher false positive rates with SITA-Faster, which current investigators reported at 15%. This proportion decreased in the second test, which may have occurred due to a “learning effect.”

Limitations of this study included higher test to re-test differences prompted by those who had more false positive errors, as well as varying time periods between previous and baseline visits, attributable to COVID-19 restrictions.