Effects of levofloxacin eye drops on ocular surface bacterial colonization and postoperative infection rate in patients undergoing blepharoplast

Background: Ocular surface bacterial colonization is a key risk factor for postoperative infection after blepharoplasty, yet clinical evidence on the impact of levofloxacin eye drops remains limited. Objectives: This study aims to evaluate the actual impact of perioperative levofloxacin eye drops on bacterial colonization density, changes in bacterial spectrum and postoperative infection rates in patients undergoing blepharoplasty. Methods: This single-center retrospective cohort study reviewed the electronic medical records of 215 patients who underwent blepharoplasty between January 2023 and January 2025. Based on the treatment they actually received, patients were categorized into two groups: the combination group (n=108), who received levofloxacin eye drops (4 times daily for 1 week) in addition to basic treatment and the control group (n=107), who received basic treatment only. The primary outcome was the incidence of postoperative infection. Secondary outcomes included the bacterial colonization positivity rate and density (days 3 and 7), changes in the bacterial spectrum, ocular surface irritation scores, wound-healing time, and adverse reactions. Results: The postoperative infection rate in the combination group was 2.78% (3/108), which was significantly lower than that in the control group (11.21% (12/107), p = 0.013). Multivariate regression analysis showed that levofloxacin use was a protective factor for postoperative infection (OR = 0.23, 95% CI: 0.07-0.81), while a history of diabetes was an independent risk factor (OR = 3.47, 95% CI: 1.14-10.55). There was no significant difference in the time to wound healing between the two groups (7.5 ± 1.2 days vs 7.7 ± 1.4 days, p = 0.258). Conclusion: Perioperative levofloxacin eye drops may reduce ocular surface bacterial colonization and the risk of postoperative infection in blepharoplasty patients without delaying wound healing.