Comparison between Tendency-Oriented Perimetry (TOP) and octopus thresholdperimetry

Objective: To compare the results obtained by a new ultra-short automated p erimetry test known as Tendency-Oriented Perimetry (TOP), which is an algor ithm based on estimation of thresholds from information gathered from adjac ent points with those obtained by a standard bracketing approach. TOP is de signed to save up to 1/5 of the time taken by standard strategy by presenti ng each stimulus once on each location (instead of 4 to 6 times per locatio n with the standard technique) and reaching a final threshold estimate by g athering information from responses to adjacent locations. Design: Prospective, multicenter, observational comparative case series. Participants/Methods: Four academic institutions provided data from testing 57 subjects, 15 with a normal ocular exam and 42 with a variety of visual field abnormalities. A total of 228 visual fields were analyzed. Two examin ations of standard thresholding testing (Octopus program 32) and two examin ations of the TOP program were obtained in each subject the same day. Main Outcome Measures: Comparison of global indices such as mean deviation (MD), square root of loss of variance (sLV), topographical defects, point b y point differences, reproducibility, sensitivity/specificity, and time req uired to complete the test. Results: Correlation coefficient of global indices between both tests was h igh, with mean deviation of r = 0.97 (SE[YX] +/- 1.65 decibels) and square root of loss variance of r = 0.93 (SE[YX] +/- 1.10 dB), Mean sensitivity te nded to be 1 dB higher while MD tended to be I dB lower with TOP strategy. Reproducibility was equally good between both tests for threshold determina tion as well as for all global indices (MS, MD per quadrant, and LV), Clust er criteria for abnormality demonstrated TOP versus 32, sensitivity of 89/8 7; specificity of 90/77; positive predictive value of 96/91; negative predi ctive value of 75/68; and accuracy of 89/84, Mean time taken by this beta v ersion of TOP was 4.05 minutes standard deviation +/- 0.55 versus the stand ard 32 version taking 14.65 minutes standard deviation +/- 3.75. Conclusions: TOP was four times faster than the traditional full-threshold technique and was successful in detecting visual field abnormalities. Defec ts with TOP tended to be smaller, shallower, and with softer edges than wit h standard approach. TOP could prove an alternative to traditional perimetr ic techniques. Ophthalmology 2000; 107: 134-142 (C) 2000 by the American Ac ademy of Ophthalmology.