SITA Fast, a new rapid perimetric threshold test. Description of methods and evaluation in patients with manifest and suspect glaucoma

Purpose: To describe and evaluate the new rapid SITA Fast computerized perimetric threshold strategy. Method: Computer simulations of visual fields were used to develop a new rapid threshold strategy, SITA Fast. In a clinical evaluation 30 patients were examined twice with each of the Full Threshold, Fastpac and SIT;I Fast strategies. Results: SITA Fast had significantly shorter test time using on average 34% of the test time when compared to the Full Threshold strategy (p<0.0001) and 53% compared to Fastpac (p<0,0001), Reproducibility; calculated as the average Root Mean Square Error, was 1.84 dB in SITA tests, and 1.99 dB and 2.02 dB with Full Threshold and Fastpac, respectively. Both SITA Fast and Fastpac showed slightly higher sensitivities on average than theoretically expected. Sensitivity differences were larger in eyes with large differences in test time. Defects detected by SITA Fast were often deep and more localised than those detected by the Full Threshold and the Fastpac strategies. Conclusion: SITA Fast tests were considerably shorter than Fastpac tests. The low test-retest variability found in the SITA Fast tests implies that it may be a sensitive test for detection of field progression.