Associations of human crystalline lens retrodots and waterclefts with visual impairment: An observational study

PURPOSE. To investigate the relationships between visual acuity, contrast sensitivity, and 11 clinicopathologic classes of opacity in the human crystalline lens. METHODS. The Somerset and Avon Eye Study is an observational population study of age-related sight-threatening eye disease, based in Bristol, UK. After excluding eyes with other visually relevant disease, data from 902 individuals aged 55 years or older were analyzed. The associations of lens features (posterior subcapsular cataract, nuclear color, nuclear white scatter, cortical spokes, anterior subcapsular cataract, vacuoles, waterclefts, coronary flakes, focal dots, retrodots, fiber folds), with refracted log minimum angle of resolution (MAR) distance acuity and Pelli-Robson contrast sensitivity, were investigated. Multivariable linear regression models using data from both eyes and taking account of the intraclass correlation between eyes were used for analysis, with the lens features and age included as potential explanatory variables. RESULTS. As anticipated from earlier studies, posterior subcapsular, nuclear, and cortical cataracts were associated with visual impairment. In addition, retrodots were strongly and independently associated in the multivariable models with both impaired visual acuity (P < 0.001) and contrast sensitivity (P < 0.001). Waterclefts were strongly associated with impaired visual acuity (P < 0.001). CONCLUSIONS. Retrodots and waterclefts are associated with visual impairment. A causal relationship between these lens features and retinal image degradation is plausible.