Preoperative antibiotic soaking of silicone sponges. Does it make a difference?

A prospective randomized trial was carried out during the years 1974 to 1981 to determine whether preoperative antibiotic soaking of silicone sponges used in retinal detachment surgery would reduce the incidence of postoperative infection and extrusion. During this period 2972 consecutive primary scleral buckles were performed and in 921 (31%) of the cases an episcleral sponge was utilized either alone or in conjunction with a hard silicone encircling band. In alternate cases the sponge was soaked in an antibiotic solution for at least 30 minutes prior to insertion. In the remaining cases the sponge was not soaked. Overall, a statistically significant (P = 0.00018) seven-fold reduction in the rate of infection or extrusion was observed in cases where the silicone sponge was soaked preoperatively in antibiotics. An additional result of the study showed the rate of sponge removal was significantly increased by the use of multiple episcleral sponges (P = 0.00002).