PROSPECTIVE EVALUATION OF NEOMYCIN SERUM CONCENTRATIONS AFTER DIRECT CORPORA CAVERNOSA IRRIGATION DURING PENILE PROSTHESIS PLACEMENT

Objectives. To determine if toxic serum levels of neomycin are generat ed after direct corpora cavernosa irrigation during penile prosthesis placement. Methods. We have used an infection prophylaxis technique th at involves directly irrigating the corpora cavernosa tissue (through the corporotomy) with 0.5% neomycin solution. Serum neomycin concentra tions were measured at hour and 4 hours after irrigation in 13 patient s undergoing penile prosthesis placement. A subset of patients who had preimplant and postimplant serum creatinine concentrations was evalua ted for changes in renal function. Results. The mean 1-hour postirriga tion serum neomycin level was 1.2 mu g/mL and the mean 4-hour postirri gation level was 1.2 mu g/mL. These serum neomycin concentrations are lower than those thought to be necessary to produce nephrotoxicity or ototoxicity. Renal function was not significantly affected by the neom ycin irrigation. Conclusions. Although aminoglycosides are ototoxic an d neomycin has the highest nephrotoxic potential of the aminoglycoside s, we conclude that direct irrigation of the corpora cavernosa with 0. 5% neomycin solution does not produce significant systemic exposure to result in nephrotoxicity or ototoxicity. One-time prophylactic neomyc in irrigation remains an effective, safe, and economic adjunct to peni le prosthesis placement.