Evaluation of the Efficacy of Ozonated Oil in Liposomes as an Adjuvant in Intravitreal Injection Prophylaxis: OPERA Study

Background/Purpose: The prevention of endophthalmitis continues to pose a significant challenge for intravitreal injections (IVIs) due to the increasing prevalence of these procedures. In response, we conducted a prospective, interventional, single-center clinical study to evaluate the collective efficacy of ozonated oil in liposomes, administered via eye drops (Ozodrop IVT™), and eyelid foam (Blefox™) in combination with povidone iodine (PI) 5% as prophylaxis. Methods: Both eyes of each patient were included and categorized into two groups. Group 1 received prophylaxis with Ozodrop IVT™ and Blefox™ for three days, followed by PI 5% before intravitreal (IV) injection. Group 2, comprising contralateral eyes, underwent standard prophylaxis with PI 5% only. Conjunctival and eyelid edge swabs were collected from both eyes at T0 (four days before IV) and T1 (10 minutes before injection, after 30-second treatment with PI 5% and washing with balance salt solution). Swabs were plated on chocolate agar for aerobic bacteria and blood agar for anaerobic bacteria. The primary endpoint assessed the difference in bacterial colonies reduction between the two groups at specified time points. The study employed a paired-eye design. Secondary endpoints included conjunctival hyperemia evaluation and subject satisfaction grade. Results: A total of 390 eyes from 195 patients (mean age: 69.6 ± 10.4 years, 48% female) were enrolled. Chocolate agar demonstrated a significant reduction in bacterial load, with decreases of 72.3% in group 1 and 50.3% in group 2 (p<0.001). Testing on blood agar also exhibited reductions, with percentages of 66.7% in group 1 and 49.7% in group 2 (p<0.001). Five (2.66%) patients reported traces, while mild was reported by only one (0.53%) patient regarding conjunctival hyperemia. No other adverse events were reported. A total of 159 (84.57%) patients reported no ocular discomfort, while mild discomfort occurred in 28 (14.89%) patients. Conclusions: The combination of ozonated oil in liposomes with PI in IV prophylaxis effectively reduced microbial load, surpassing the efficacy of standard prophylaxis with PI alone. This finding suggests a potential enhancement in intravitreal injection safety through the incorporation of ozonated oil in liposomes as an adjuvant therapy.