Presoaked IOLs show dual action

Intraocular lenses (IOLs) soaked in antibiotics have antimicrobial properties, according to results published in the October issue of the Journal of Ocular Pharmacology and Therapeutics.

Edward F. Smith of the department of ophthalmology at the State University of New York (SUNY), US and colleagues immersed six groups (each group, n=8–10) of commercially available IOLs in fourth-generation fluoroquinolones as follows: 1.8 µg/mL moxifloxacin for 60 minutes; 5 mg/mL moxifloxacin for one minute; 5 mg/mL moxifloxacin for 60 minutes; 0.48 µg/mL gatifloxacin for 60 minutes; 3 mg/mL gatifloxacin for one minute; and 3 mg/mL gatifloxacin for 60 minutes. A control group of IOLs was soaked in saline for 60 minutes. The IOLs were placed in agar with an overlay of S. aureus and after 24 hours, the team measured bacterial kill zones.

Among the groups soaked in lower-strength doses of antibiotic for 60 minutes, the 0.48 µg/mL gatifloxacin and saline produced no measurable bacterial kill zone, whereas the 1.8 µg/mL moxifloxacin group produced a bacterial kill zone of 3.88±3.18 mm. A kill zone of ≥33 mm was achieved by all groups soaked in high dose fluoroquinolones: for the 5 mg/mL moxifloxacin group (one minute), this was 38.80±3.74 mm; 3 mg/mL gatifloxacin (one minute), 34.30±1.34 mm; 5 mg/mL moxifloxacin (60 minutes), 33.56±1.42 mm; 3 mg/mL gatifloxacin (60 minutes), 33.67±0.50 mm.

Thus the researchers concluded that soaking IOLs in high (commercial) levels of fluoroquinolones produces IOLs with antimicrobial properties in vitro. The widest bacterial kill zone was achieved with IOLs immersed for one minute in 5 mg/mL of moxifloxacin.