Bacterial flora in relation to cataract extraction. V. Effects of topical antibiotics on the preoperative conjunctival flora.

In a randomized study comprising 60 patients, six different prophylactic regimens were evaluated for their effectiveness in eradicating bacteria on the conjunctivas before surgery. Gentamicin sulfate ophthalmic solution was the only antibiotic able to eliminate bacteria in almost all of the examined patients. The other drugs (chloramphenicol solution, oxytetracycline-polymyxin B ointment, sulphamethizole, bacitracin-neomycin and ristocetin-polymyxin B solutions) were not effective, although most of the isolated strains were sensitive to the respective antibiotics, probably because of the short treatment period (18 h). The problem of prophylactic therapy of ophthalmology is discussed, and some guide lines are given.