Evaluation of the efficacy of contrast sensitivity measures for the detection of early primary open-angle glaucoma.

We investigated the relative efficacy of contrast sensitivity (CS) measures for the identification of early primary open-angle glaucoma (POAG) patients. The contrast sensitivity function (CSF) was sampled at five spatial frequencies using a standard oscilloscope technique and measures of CS were also obtained using the Cambridge Gratings, Pelli-Robson CS Charts, Melbourne Edge Test (MET), and the High and Low Contrast Bailey-Lovie Letter Charts. Of the techniques evaluated, the High and Low Contrast Bailey-Lovie Letter Charts and the oscilloscope technique at the peak of the CSF exhibited the highest levels of sensitivity and specificity for differentiating between the POAG patients and normals. However, the relatively low levels of sensitivity and specificity obtained for the oscilloscope and chart tests overall indicate that, regardless of the pass/fail criterion selected, CS is unsuitable for screening for early POAG.