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The authors present computer perimetric simulation results of a white Goldmann Size III variant of the ZEST Bayesian thresholding procedure, called ARREST (Australian Reduced Range Extended Spatial Test). ARREST censors threshold testing at test points where the algorithm has already found that sensitivity is < 17dB. Time thus saved is used to examine additional test point locations near the detected defect. In computer simulations comparing their method to ZEST, ARREST used 25% to 40% fewer test presentations, while showing sensitivity to detect visual field progression that was similar to that of ZEST.
These simulation findings are consistent with the work of Gardiner and colleagues,1,2 confirming that censoring SAP testing below approximately 19 dB may save testing time without impairing detection of visual field progression. How best to use resulting time savings remains an open question. Time savings might be used as the authors suggest, to provide higher spatial definition in areas adjacent to detected loss. Alternatively, savings might be used to test more carefully for macular field loss,3,4 or to simply shorten testing time in the hope of achieving improved clinical compliance with currently recommended visual field testing frequencies.
As the authors note, we also have good evidence that perimetric progression detection can be significantly improved simply by using test stimuli that are larger than Size III,5 and by progressively increasing step size as scotomas deepen.6,7 Thus, censoring might be beneficially combined with use of larger stimuli and variable step size. It is well past time for us all to work decisively toward the development of practical and widely-available visual field testing strategies that hasten and simplify detection of progressive visual field loss.