Evaluation of a Lens Opacities Classification System
M. C. Leske, L. T. Chylack Jr, R. Sperduto, P. Khu, S. Y. Wu and D. McCarthy
Department of Community and Preventive Medicine, State University of New York at Stony Brook 11794-8036.
A simple system, based on standard photographs, has been developed to
classify lens opacities. The system allows the definition of cataract cases
and noncases according to the location of lens opacification (nuclear,
cortical, posterior subcapsular) and its extent (early or more advanced).
Evaluation of the system has shown good to excellent reproducibility for
clinical and photographic classifications. Comparisons of clinical and
photograph-derived gradings has shown generally good agreement in
classifying the presence and type of cataract; this agreement is highest
for nuclear cataract. Photographic gradings of posterior subcapsular and,
to a lesser degree, cortical opacities tend to underestimate the extent of
opacification found by clinical gradings. The Lens Opacities Case-Control
Study system is simple, reproducible, and easy to implement; it is offered
for use in case-control and other cross-sectional studies of cataract with
compatible classification goals.
