A Sensitive Test of Disability Glare

Abstract

Visual acuity alone is a poor indicator of visual performance in patients with media disturbances. Hess and Woo (1978) demonstrated that cataract patients with similar levels of visual acuity could have markedly different contrast sensitivity functions. It has been suggested that the detrimental effect that lens opacities have on vision can be better evaluated by the assessment of disability glare. Disability glare causes a reduction in visual performance that results from intraocular light scatter reducing the contrast of the retinal image. Disability glare is assessed by determining the extent to which the introduction of a bright light source close to a test target impairs the visibility of that target. Paulsson and Sjostrand (1980) found that cataractous patients who had good visual acuity and only moderately reduced contrast sensitivity under normal testing conditions, showed severe contrast sensitivity deficits in the presence of a glare source.