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Contrast sensitivity measurement in the detection of primary open angle glaucoma

Wood, Joanne M. and Lovie-Kitchin, Jan E. (1991) Contrast sensitivity measurement in the detection of primary open angle glaucoma. In Proceedings Perimetry Update 1990/1991 Proceedings of the IXth International Perimetric Society Meeting, pages pp. 82-86, Malmo, Sweden.

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Abstract

Contrast sensitivity is a well established psychophysical technique for identification and monitoring of visual dysfunction. Traditional methods of contrast sensitivity measurement using oscilloscope-based techniques are too time-consuming and expensive to be clinically viable. A number of chart-based test have been introduced to simplify measurement. These employ either grating or letter targets and incorporate criterion-free psychophysical strategies such as two alternate forced choice to reduce measurement error. The aim of the study was to determine the potential of such tests in the detection of primary open angle glaucoma. Twenty primary open angle glaucoma, 20 ocular hypertensive patients and 20 normal control subjects were investigated using the following chart-based contrast sensitivity tests: Cambridge Gratings, Pelli-Robson Letter Charts, High and Low Contrast Letter Charts and Melbourne Edge Test. The validity and diagnostic capability of each was evaluated with respect to oscilloscope-based contrast sensitivity and to Humphrey Field Analyzer central visual fields assessment (program 24-2), disc photographs and intraocular pressures. The validity of each of the chart-based tests relative to the oscilloscope-based standard was poor (r < 0.70). ROC curves demonstrate low sensitivity and specificity (poor diagnostic capacity) at the recommended cut-off levels for all of the contrast sensitivity tests. Alternative criteria are suggested to improve diagnostic capacity.

Item Type:Conference Paper
Status:Published
Subjects:320000 Medical and Health Sciences > 320900 Optometry
ID Code:5654
Deposited By:Bonham, Mark
Deposited On:05 July 2007
Copyright Owner:Copyright 1991 (please consult author)
Additional Information:For more information please contact the author: j.lovie-kitchin@qut.edu.au