EVALUATION OF LENS OPACITIES CLASSIFICATION-SYSTEM-III APPLIED AT THESLITLAMP

The Lens Opacities Classification Systems (LOCS III) was developed and standardized using photograding. The purpose of this study was to ass ess the validity of LOCS III at the slitlamp and to compare slitlamp w ith photograding. To do so, two independent observers graded cataract at the slitlamp and in photographs from two sets of patients; the firs t set consisted of 205 eyes (193 acceptable photographs) and the secon d set of 51 eyes (51 photographs). The 95% tolerance limits (TL) for g rading at the slitlamp ranged from 0.9 to 1.8 for the first set and 0. 6 to 1.2 for the second (intraclass correlation coefficients 0.79 to 0 .91 vs. 0.70 to 0.97, respectively). Specifically, there was a signifi cant decrease in 95% TL for cortical and nuclear color. For the first set of photograding, the 95% TL were 0.3 to 0.6 between the two observ ers and 0.6 to 0.8 for the same observer at two different sessions. Si milar results were found for photograding the second set. The 95% TL f or comparing slitlamp and photograding were generally >1.0. The result s suggest that (1) LOCS III at the slitlamp has 95% TL only slightly w orse than those for LOCS III photogradings; (2) LOCS III slitlamp grad ing for cortical and nuclear color improves with practice; and (3) the slitlamp and photographic gradings cannot be used interchangeably.