Blindness from cataract formation in leprosy.

Of 744 leprous patients, 61 (8.2%) had cataract-induced blindness; 46 patients (6.2%) were unilaterally blind and 15 (2.0%) were bilaterally blind. The mean age of patients with cataracts was 63.4 years in the tuberculoid-type leprosy and 56.4 years in the lepromatous type. The appearance of cataracts in lepromatous patients at an earlier age than in tuberculoid patients is significant (p less than 0.005). Of 41 cataractous eyes with posterior iris synechiae, 42.1% were observed in patients with tuberculoid-type leprosy and 59.1% in patients with the lepromatous type. Histopathological examination of 24 lenses showed that irregularities of the lens epithelium were present in 79.2%. Posterior iris synechiae were seen in 66.7% and fibrous pseudometaplasia in 41.7%. Posterior migration of the lens epithelium in the posterior subcapsular area was observed in 54.2%. In view of these clinical and histopathological findings, we discuss the probability that most cataracts in leprous patients are complicated in nature.