Concentrations of Levofloxacin, Ofloxacin, and Ciprofloxacin in Aqueous Fluid and Corneal Tissue after Topical Ophthalmic Administration in Human Volunteers before Penetrating Keratoplasty

Abstract

Abstract: : Purpose: This study examined concentrations of commercially available levofloxacin 0.5%, ofloxacin 0.3%, and ciprofloxacin 0.3% topical ophthalmic solutions in aqueous fluid and corneal tissue of human volunteers scheduled for penetrating keratoplasty. Methods: Sixty-five patients scheduled for PK were enrolled in a prospective, double-masked, multicenter study. Patients had to have an intact corneal epithelium and minimal or no corneal edema (pachymetry < 650 µm). After informed consent, patients were randomized to receive levofloxacin 0.5%, ofloxacin 0.3%, or ciprofloxacin 0.3%. Instillation of fluoroquinolone began with 1 drop applied 15 minutes before surgery and 3 minutes after application of 1 drop of proparacaine. A second drop was applied 5 minutes after the first. A 100- to 150-µL sample of aqueous fluid was obtained at the outset of surgery through the corneal trephination wound. Aqueous samples and excised corneas were stored frozen at -70°C. HPLC was used to determine drug concentrations. Results: Results for a total of 65 corneal tissue and 59 aqueous fluid samples are shown in Table 1. Kruskal-Wallis one-way analysis of variance on ranks showed statistically significant differences among concentrations of fluoroquinolone in aqueous fluid (P < .001) and corneal tissue (P = .03). Pairwise multiple comparison (Dunn’s Method) compared each fluoroquinolone to the others. In corneal tissue, LVFX attained a statistically significantly higher concentration than CFLX (P < .05). In aqueous fluid, LVFX attained a statistically significantly higher concentration than both CFLX and OFLX (P < .05). Conclusions: LVFX penetrates human corneal tissue to reach significantly higher concentrations in aqueous fluid than either OFLX or CFLX and is present in corneal tissue in significantly higher concentration than CFLX. Table 1. Concentrations of fluoroquinolones in aqueous and cornea  

Keywords: antibiotics/antifungals/antiparasitics • cornea: stroma and keratocytes • pharmacology