Effectiveness of liposomal ozonised oil in reducing ocular microbial flora in patients undergoing cataract surgery

Purpose: To evaluate the antimicrobial effectiveness of a liposomal ozonised-oil solution used as a home therapy in patients undergoing cataract surgery. Antimicrobial efficacy was evaluated as the reduction in the bacterial load of the most common bacteria isolated from endophthalmitis cases. Setting: Twenty Italian experimental centres of the ELOOM (Effectiveness of Liposomal Ozonised-oil on Ocular Microbial flora before cataract surgery) study group. Design: An interventional, non-randomised, paired-eye designed, Phase 4 clinical study METHODS:: A total of 174 patients undergoing cataract surgery were divided into two groups: the study group (174 eyes) underwent surgery and received an isotonic ophthalmic solution of 0.5% ozonised oil in liposomes plus hypromellose treatment (2 drops 4 times/day), and the control group (174 contralateral eyes) was treated with saline solution. The treatment lasted for 3 days. Subconjunctival swabs were taken from both eyes of each patient at T0 (the day before starting the treatment, 4 days before surgery) and at T4 (after 3 days of treatment, 10 min before surgery) and sent to the laboratory within 24 h of collection for microbiological analysis. Results: Thirty percent of swabs taken at T0 were sterile. Contaminated swabs had a high prevalence of coagulase-negative staphylococci, including Staphylococcus epidermidis, and more than 60 different bacterial species were isolated. A significant reduction in microbial load was observed after treatment (>90% of the samples). The microbial load in the control group remained unchanged. Conclusions: Liposomal ozonised oil reduced the microbial burden after topical administration in a large study population.