National survey on bullous keratopathy in Japan

Purpose: To present the results of a national survey on bullous keratopathy (BK) in Japan. Methods: A cross-sectional national survey was conducted for 963 eyes with BK seen between 1999 and 2001 by members of the Japan Cornea Society. Demographic characteristics, type of surgery, complications, and postoperative outcome were analyzed. Results: BK accounted for 24.2% (963 eyes) of total keratoplasties performed during the period. Graft clarity was maintained in 77.4% of cases, and immunologic rejection and elevated intraocular pressure was noted in 10.8% and 15.3%, respectively. Cataract surgery was the most common cause of BK (n = 428, 44.4%), and phacoemulsification and aspiration were performed in approximately 40% of cases. BK secondary to laser iridotomy (LI) was the second most common cause of BK (n = 225, 23.4%). LI was performed as a prophylactic measure in approximately one half of these cases. BK developed with a mean duration of 6.8 years after LI. Fuchs dystrophy was the cause of BK in 18 eyes (1.9%). Conclusions: The causes of BK in Japan are considerably different from those in other Western countries. LI-related BKs showed a remarkably high number, whereas Fuchs dystrophy was observed only rarely.