THE RELATIONS BETWEEN CLINICAL CLASSIFICATION OF CATARACT AND LENS HARDNESS

`Hardness' of the cataractous lens is one of the major factors influen cing the suitability of a patient for phacoemulsification. Surgeons sh ould be able to estimate hardness when choosing patients for this meth od of cataract extraction. The aims of the study mere to investigate t he relationship between the clinical appearance of cataracts and their hardness. Ninety-one lenses were studied from patients undergoing end ocapsular cataract extraction. Lenses were assessed using a classifica tion based on the Lens Opacities Classification System II and hardness mas assessed using an automated lens guillotine. The degree of nuclea r sclerosis and the age of the patient were found to influence lens ha rdness. Regression analysis showed that 56% of the variation in hardne ss could be explained in terms of age and the degree of nuclear sclero sis. The presence of posterior subcapsular and cortical cataract did n ot influence hardness. These findings confirm our clinical suspicions and enable surgeons to make a more objective analysis of hardness prio r to phacoemulsification.