September 1991
Volume 32, Issue 10
Free
Articles  |   September 1991
Peripheral color contrast. A new screening test for preglaucomatous visual loss.
Author Affiliations
  • T C Yu
    Department of Clinical Ophthalmology, University of London, United Kingdom.
  • F Falcao-Reis
    Department of Clinical Ophthalmology, University of London, United Kingdom.
  • W Spileers
    Department of Clinical Ophthalmology, University of London, United Kingdom.
  • G B Arden
    Department of Clinical Ophthalmology, University of London, United Kingdom.
Investigative Ophthalmology & Visual Science September 1991, Vol.32, 2779-2789. doi:
  • Views
  • PDF
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      T C Yu, F Falcao-Reis, W Spileers, G B Arden; Peripheral color contrast. A new screening test for preglaucomatous visual loss.. Invest. Ophthalmol. Vis. Sci. 1991;32(10):2779-2789.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

A new test of peripheral color contrast is described. A high-definition color monitor driven by a personal computer with a graphics interface card displays an annulus subtending 25 degrees at the eye. The color contrast between the annulus and the background can be varied. Forty-five degrees of the annulus is randomly removed in one of four quadrants. Patients are asked to identify the position of the gap while fixating a central spot. The minimum color contrast between annulus and background at which the identification is possible is between 13-16% for the protan, deuteran, and tritan axis in normal subjects. This threshold value changes little with age, refractive error, or pupillary aperture, and test-retest variability is low. Testing one eye takes only 1-2 min. The test was applied to ocular-hypertensive and glaucomatous patients. All patients with glaucoma had thresholds greater than two standard deviations (SD) above the normal mean. In addition, 97% of glaucoma patients had thresholds greater than four SDs, and 95% had thresholds more than five SDs above the normal mean. Most patients with ocular hypertension and clinical signs indicating a low or medium risk of conversion to glaucoma had thresholds under the upper limit of normal. High-risk patients with ocular hypertension fell into two groups. One approximated to normal; the other had elevated thresholds, which in many cases were more than four SDs above the normal mean. The epidemiologic consequences of this test are discussed.

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×