Risk of endophthalmitis after intravitreal drug injection when topical antibiotics are not required: The diabetic retinopathy clinical research network laser-ranibizumab-triamcinolone clinical trials

Objective: To report the incidence of endophthalmitis after intravitreal drug injection by means of a standardized procedure that does not require topical antibiotics, sterile gloves, or a sterile drape. Methods: Intravitreal injections of preservative-free triamcinolone acetonide or ranibizumab were administered in 2 prospective randomized clinical trials performed by the Diabetic Retinopathy Clinical Research Network. The standardized procedure for these trials requires the use of a topical combination product of povidone-iodine, a sterile lid speculum, and topical anesthetic, but does not require the use of topical antibiotics before, on the day of, or after injection. Results: As of February 23, 2009, a total of 3226 intravitreal injections of ranibizumab and 612 injections of preservative-free triamcinolone had been administered. Topical antibiotics were given on the day of injection in 361 (9.4%) of the 3838 cases, for several days after injection in 813 cases (21.2%), on the day of injection and after injection in 1388 cases (36.2%), and neither on the day of injection nor after injection in 1276 cases (33.3%). Three cases of culture-positive endophthalmitis occurred after ranibizumab injections (0.09%), and no cases occurred after triamcinolone injections. In all 3 cases of endophthalmitis, topical antibiotics were given for several days after the injection but not before injection. Conclusions: The results suggest that a low rate of endophthalmitis can be achieved by means of a protocol that includes use of topical povidone-iodine, a sterile lid speculum, and topical anesthetic, but does not require topical antibiotics, sterile gloves, or a sterile drape.