For 32 eyes tested for glare disability after undergoing extracapsular cataract extraction with implantation of posterior chamber intraocular lenses, the mean contrast threshold in the presence of the glare source was 23% for undilated pupils and 31% with dilation. A regression analysis of glare scores as a function of the amount of posterior capsule opacification showed a significant (P less than .00001) association between the two.