Associations between lens features assessed in the Oxford Clinical Cataract Classification and Grading System

PURPOSE: To study the associations between eleven lens features graded according to the Oxford Clinical Cataract Classification and Grading System (OCCCGS). METHOD: 560 subjects taking part in the Melton Eye Study had their lenses graded according to the OCCCGS by one of two examiners. Associations between features were examined using log-linear models for categorised grades. Adjustment was made for age, sex and grader. RESULTS: Within subjects, the two nuclear features, white nuclear scatter and brunescence, are closely related with one another, as are coronary flakes and focal-dots, but these two groupings are negatively associated. Cortical spoke, fibrefolds and waterclefts are all associated with one another and this group is positively associated with coronary flakes and focal-dots. Posterior subcapsular and anterior subcapsular opacity are associated with one another and with cortical spokes. A within-eye analysis gives similar results. CONCLUSION: These associations may be important in defining cataract subtypes and in identifying minor features that indicate early cataract development.