Comparison of the efficacy of povidone–iodine 1.0%, 5.0%, and 10.0% irrigation combined with topical levofloxacin 0.3% as preoperative prophylaxis in cataract surgery

Abstract

To compare the efficacy of povidone-iodine 1.0%, 5.0%, and 10.0% in combination with topical levofloxacin 0.3% in reducing the preoperative conjunctival bacterial load before cataract surgery. Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. Randomized clinical trial. This study enrolled patients scheduled for cataract surgery between July 2010 and January 2011. All patients received topical levofloxacin 0.3% 4 times on the preoperative day and were randomly assigned to these study groups: Group 1 (povidone-iodine 1.0%), Group 2 (povidone-iodine 5.0%), and Group 3 (povidone-iodine 10.0%). In all groups, the conjunctiva was flush irrigated with 10 mL of povidone-iodine of the respective concentration. Conjunctival specimens were obtained at 4 timepoints: baseline (no-surgery eye), before povidone-iodine irrigation, after povidone-iodine irrigation, and at the end of surgery. All specimens were inoculated onto blood and chocolate agars and into thioglycolate broth. The study was completed by 271 patients. In the control smear (no-surgery eye), no significant difference in positive cultures was found. After 10 mL povidone-iodine irrigation, a considerable reduction in the conjunctival bacterial load occurred in all groups. The difference in positive cultures was statistically significant between Group 1 and Group 3 (P=.024) and between Group 2 and Group 3 (P=.029). Coagulase-negative Staphylococcus was the most commonly isolated bacteria in all groups. Povidone-iodine 10.0% was more effective than povidone-iodine 1.0% and 5.0% in decreasing the conjunctival bacterial load before surgery. No author has a financial or proprietary interest in any material or method mentioned.