Purpose: To compare the sterilization effectivity of topical povidone-iodine, ciprofloxacin, and ofloxacin on the conjunctival bacterial flora.
Methods: One hundred sixty-four eyes of 164 patients scheduled for cataract surgery were prospectively analyzed. Conjunctival cultures were obtained 1 day before the surgery without any topical application in all patients. Conjunctival flora was examined in 53 eyes of 53 patients (Group I) 15 min after 5% topical povidone-iodine application on the day of the surgery. Fifty-four eyes of 54 patients (Group II) received 1 drop 0.3% ciprofloxacin at 12 pm 1 day before the operation and 4 drops at 15 min intervals on the day of the surgery. Another 57 eyes of 57 patients (Group III) received 0.3% ofloxacin in the same application mode as ciprofloxacin. Conjunctival cultures were taken in all patients 15 min after last drop of topical antibiotic application.
Results: Only coagulase-negative staphylococci were isolated from 75.4% in Group I, 72.2% in Group II, and 59.6% in Group III on pretreatment culture. Different types of bacteria such as Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Proteus spp., Micrococcus spp. were identified in other patients. Pretreatment conjunctival flora of Group I and Group II were similar (P>0.05), but it was significantly different in Group III (P<0.05). After topical application no bacterial growth was observed in 77.3% in Group I, 92.5% in Group II, and 66.6% in Group III. The difference between Group I and III was insignificant (P>0.05), but bacterial eradication effectiveness was significantly higher in Group II than that of other groups (P<0.05). Post-treatment cultures showed same bacterial flora as pretreatment cultures in 14.9% in Group I, 1.8% in Group II, and 19.2% in Group III. The difference between Group I and Group III was statistically insignificant (P>0.05) and the difference between Group II and other groups was statistically significant (P<0.05). Four eyes (7.5%) showed different types of bacterial growth from pretreatment flora in Group I, which were seen in 3 eyes (5.5%) in Group II and in 8 eyes (14%) in Group III. The differences between groups were statistically insignificant (P>0.05).
Conclusion: Ciprofloxacin seems to be more effective in conjunctival sterilization. In consideration with high variety of bacterial flora in pretreatment period in ofloxacin group, ofloxacin seems to be superior to povidone-iodine on the reduction of bacterial flora on the conjunctiva.