In Vitro Cataract Classification Systems : A Review
In early days, since the whole lenses were readily available from intracapsular cataract surgery, so the early systems of cataract classification1,2,3 were developed for use almost exclusively with isolated lenses. These systems were largely qualitative, and they emphasized nuclear color as the index of the severity of cataract formation; lighting systems that improved visualization of cortical and subcapsular morphologic detail had not been developed. Before 1976, lens and cataract research emphasized studies of animal lenses, and researchers erroneously believed these animal lenses to be adequate models of the human lens. In 1976, the CCRG was established to increase understanding of the mechanisms of human cataract formation. One of the CCRG's goals was to establish a lens classification system to help lens researchers study the biochemical and biophysical properties of the cataractous lens and compare them with those of normal lenses. Such a system would facilitate biochemical, bio