Re: “Is Risk of Artificial Urethral Sphincter Cuff Erosion Higher in Patients With Penile Prosthesis?”

Abstract

We read this article with great interest and appreciate the work of the authors.1 The authors investigated concomitant penile prosthesis (PP) implantation as a potential risk factor for cuff erosion in men who underwent artificial urethral sphincter (AUS) placement for stress urinary incontinence after radical prostatectomy. They hypothesized that concomitant PP might promote AUS cuff erosion because of impaired corporal blood supply and/or increased pressure on the cuff. They retrospectively compared AUS cuff erosion and explantation rates in patients with and without PP implantation for erectile dysfunction (ED). They concluded that men with AUS and PP implantation had a significantly higher risk of cuff erosion and explantation rate from any cause. They advocated that continence should be restored over erectile function in high-risk and elderly patients and PP implantation should be discouraged in challenging cases. We have some questions and comments about their findings. The findings of this study showed that patients in the AUS-only group were more likely to have high submuscular placement of the pressure-regulating balloon. Could the location of the pressure-regulating balloon affect erosion rates and thus cause any bias in patient selection? Possible trauma during urethral catheterization without AUS deactivation might increase the risk for cuff erosion.2 Were there any patients who underwent catheterization without AUS deactivation? Bladder neck contracture, which sometimes occurs in patients after radical prostatectomy, might be a possible risk factor for AUS cuff erosion.3,4 Were there any patients who had postoperative bladder neck contracture and were operated on for this reason? Did all patients use phosphodiesterase type 5 inhibitors for erectile function rehabilitation before PP implantation? Did the authors have any data regarding the comparison of erosion rates between men who were previously treated with phosphodiesterase type 5 inhibitors and those who were not? The authors reported that patients with cuff erosion had a significantly lower testosterone level compared with patients without erosion. Were there any patients who were treated with adjuvant radiotherapy and/or androgen ablation therapy? These two treatment modalities could negatively affect urethral vascularization and potentially cause a significant decrease in testosterone level. How many patients had preoperative ED? ED is believed to be a precursor sign for vascular disease and a potential marker for atherosclerosis, endothelial dysfunction, and cardiovascular disease.5 Although this recent study reported no difference between the AUS-only and AUS-PP groups for coronary artery diseases, ED was significantly higher in the AUS-PP group and urethral blood flow might have already deteriorated in the patients with ED. Further, PP placement might be an additional risk factor for cuff erosion. Could the authors make any comment on the speculation that the rate of cuff erosion was higher in men with existing ED because of an abnormal urethral blood supply?