Abstract
Purpose :
To compare the efficacy of 1-day versus one-hour application of a topical fourth-generation fluoroquinolone in reducing preoperative conjunctival bacterial flora and preventing aqueous humor contamination in patients undergoing cataract surgery.
Methods :
Study subjects scheduled for cataract surgery (n=38) were recruited and randomized to receive either topical 0.5% moxifloxacin or 0.6% besifloxacin for 1 day (QID, n=17) or 1 hour (q5 minutes for 3 doses, n=21) preoperatively. Cultures were collected from the inferior palpebral conjunctival sac using a culture swab moistened with sterile tryptic soy broth at baseline (T0) and after topical antibiotic applications (T1). All eyes underwent standard periocular disinfection using povidone-iodine on the eyelids and surrounding skin. Aqueous humor samples of approximately 0.01 ml were collected intraoperatively (T2) from all subjects immediately after the initial paracentesis incision and cultured. All three conjunctival and aqueous humor samples were immediately inoculated onto blood and chocolate agar plates and in tryptic soy broth. Subsequent positive bacterial growth was identified and compared.
Results :
The rate of positive baseline conjunctival cultures (T0) was 47% (n=8) in the 1-day group and 61.9% (n=13) in the one-hour group (p = 0.360). The rate of positive conjunctival cultures after administration of topical antibiotics (T1) was 0.0588% (n=1) in the 1-day group as compared with 0.095% (n=2) in the one-hour group, with no significant differences (p = 0.679). Among the aqueous humor samples (T2), the rate of positive cultures was 0.0588% (n= 1) in the 1-day group and 0.095% (n=2) in the one-hour group (p = 0.679). Of the positive baseline conjunctival cultures, the most commonly isolated bacteria in either group was Staphylococcus epidermidis (66.7% of baseline, n=14).
Conclusions :
In this study, topical applications of a fourth-generation fluoroquinolone for one hour is as effective as its application for one day in reducing the perioperative conjunctival bacterial load and preventing aqueous humor contamination. These results may support that a shorter duration of topical antibiotic prophylaxis may be sufficient prior to cataract surgery, however a larger study will be needed to confirm results found in this study.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.