Comparing significance and magnitude of glaucomatous visual field defects using the SITA and Full Threshold strategies

PURPOSE: To evaluate and compare visual field test results as presented by the Statpac interpretation tools in tests obtained with the new short SITA Standard and the even shorter SITA Fast strategies to the traditional Humphrey Full Threshold strategy.

SUBJECTS AND METHODS: One eye of each of 44 glaucoma patients was examined four times with each of the Humphrey SITA Standard, SITA Fast, and Full Threshold strategies. Another 21 eyes of 21 normal subjects had one eye examined once with each of the three strategies.

RESULTS: Average light sensitivity was highest with the shortest SITA Fast strategy and lowest with the longest Full Threshold strategy. Magnitude of field loss as defined by the Statpac Mean Deviation (MD) did not differ between the three strategies. In the glaucoma patients, both SITA strategies showed larger number of significantly depressed points in Statpac probability maps than the Full Threshold strategy. In the normal subjects SITA Standard showed more significantly depressed points, close to the statistically expected number, at the lowest probability level (p<5%) than both Full Threshold and SITA Fast. At higher probability levels (p<1%) SITA Standard and Full Threshold showed similar numbers of significantly depressed points.

CONCLUSION: Both SITA Standard and SITA Fast identified at least as much significant glaucomatous field loss as the Full Threshold using the Statpac interpretation tools.