Bacterial culture after three sterilization methods for cataract surgery

Purpose To compare bacterial cultures from three sterilization methods immediately before and after cataract surgery. Design A prospective randomized open-label group-comparison study. Methods We investigated 75 eyes in 73 consecutive patients undergoing cataract surgery. After swabbing the eyelid and surrounding area, patients were randomly assigned to one of 3 eye-washing methods: patients administered one drop of 5 % povidone–iodine (Group A); patients whose conjunctival sac was washed with 0.02 % chlorhexidine while everting the eyelid (Group B); or 0.02 % chlorhexidine as above but without eyelid eversion (Group C). In each group, specimens were collected from the conjunctival sac immediately before and after eye washing and again at completion of surgery, along with aqueous humor. The post-surgical condition of the corneal epithelium and the severity of anterior chamber inflammation were assessed by use of a slit-lamp microscope. Results In Groups A and C, the percentage of eyes with conjunctival bacteria decreased significantly from immediately before to immediately after washing (Group A, p = 0.008; Group C, p = 0.016), but there was no significant decrease in Group B ( p = 0.125). Slit-lamp microscopy showed that inflammation of the anterior chamber 1 day after surgery was significantly milder in Group C than in Group B ( p = 0.032). Conclusion Eye-washing methods without eyelid eversion are more effective in reducing conjunctival bacteria before surgery and anterior chamber inflammation after surgery than those with eyelid eversion.