Abstract
Purpose:
To evaluate endophthalmitis rates after intravitreous injection with and without pre- or post- injection antibiotics as well as protocol violations involving omission of topical betadine in the Diabetic Retinopathy Clinical Research Network (DRCR.net).
Methods:
The DRCR.net uses a standardized intravitreous injection procedure across 7 clinical trials for diabetic macular edema and/or diabetic retinopathy. The procedure requires topical povidone-iodine allowed to be present for at least 30 seconds over the injection site, use of a sterile lid speculum, and topical anesthetic. Omission of povidone-iodine is a protocol violation. However topical antibiotics prior to, on the day of, or after injection are not required but are permitted based on investigator discretion. Prohibition of talking during the procedure, use of sterile gloves or a sterile drape also is at investigator discretion. Injections were given after aflibercept, bevacizumab, ranibizumab, or saline was drawn from a single use vial. Diagnosis of endophthalmitis was based on investigator’s judgment<br /> <br />
Results:
Between June 2006 and October 31, 2014, 11 cases of endophthalmitis occurred following 24,065 intravitreous injections administered to 2,598 eyes (0.046% of injections, 0.42% of eyes). In only 2 eyes povidone iodine was not administered over 13 injections. Both eyes developed endophthalmitis. Excluding the injections given without povidone iodine, of the 10,447 injections (43%) using topical antibiotics, 6 eyes (0.057%) developed endophthalmitis compared with 3 eyes (0.022%) out of 13,605 (57%) injections administered without using topical antibiotics (P value = 0.19).
Conclusions:
Results suggest that not including topical povidone-iodine prior to intravitreous injections substantially increases the risk of endophthalmitis. Furthermore, a low rate of endophthalmitis can be achieved without the use of topical antibiotics when the technique includes the use of topical povidone-iodine, a sterile eyelid speculum and topical anesthetic.