Purpose:
To develop databases from a common set of normal participants for probability plots for Humphrey size III, size V, Motion Perimetry and Matrix Perimetry; to compare the normal and abnormal probability plot results of the 4 perimetric tests.
Methods:
We computed empiric probability plots from data collected from testing 60 common normal participants (ages 40 - 78) with the four perimetry types above. We then analyzed the probability plots of 120 Glaucoma patients (ages 38 - 81, mean deviation -6.67±4.4). We counted the number of test locations without and with loss at <1%, <2%, and <5% levels and compared the number of normal and abnormal test locations from our normative databases using the four tests (Figure). We used two-way repeated measures ANOVA to compare the counts of normal and abnormal test locations among the tests.
Results:
The graph shows the differences in the number of normal and abnormal test locations flagged by the four tests’ probability plots (average of two visits). For the number of normal test locations, sizes III and V were not significantly different from each other. But both III and V were significantly different from Motion and Matrix (all at p<.001); Matrix had significantly fewer normal test locations than the other tests (p<.001).
Conclusions:
While clinically significant differences among the tests were small (of the order of 2-3 abnormal test locations per visual field exam), Matrix testing produced significantly more abnormal test locations.
Keywords: visual fields • perimetry • optic nerve