TWO-YEAR OUTCOME OF UNILATERAL SURAL NERVE INTERPOSITION GRAFT AFTER RADICAL PROSTATECTOMY HONG GEE SIM, MICHEL KLIOT, PAUL H. LANGE, WILLIAM J. ELLIS, THOMAS K. TAKAYAMA, AND CLAIRE C. YANG ABSTRACT Objectives. To study 41 men treated for prostate cancer with unilateral nerve-sparing radical prostatec- tomy and contralateral sural nerve grafting from January 2000 to September 2003. Methods. Patients were considered for sural nerve grafting if they were considered at high risk of extra- capsular extension before or during surgery, were younger than 70 years of age with good preoperative erectile function, were sexually active, and had no significant risk factors for erectile dysfunction. Potency was assessed by patient-reported questionnaires, including the International Index of Erectile Function erectile domain and Rigiscan testing. Results. The mean follow-up was 27.4  14.5 months. At 24 months, 24 (63.2%) of 38 men had erections sufficient for intercourse, with or without phosphodiesterase type 5 inhibitor use. Four men had partial erections that were occasionally satisfactory (10.5%), and 10 men reported no sexual activity, no sponta- neous erections, or partial erections unsatisfactory for intercourse (26.3%). In contrast, in a group of 49 men who underwent unilateral nerve-sparing prostatectomy without nerve grafting during the same period at our institution, 13 (26.5%) had rigid erections adequate for intercourse with or without phosphodiesterase type 5 inhibitor use at 24 months of follow-up. Conclusions. At 24 months of follow-up, men who had undergone unilateral nerve-sparing prostatectomy with contralateral sural nerve interposition graft repair of a cut cavernosal nerve had a greater rate of return of erectile function than men undergoing unilateral nerve-sparing prostatectomy alone. UROLOGY 68: 1290–1294, 2006. © 2006 Elsevier Inc. T he recovery of erectile function after radical prostatectomy is highly dependent on the num- ber of intact neurovascular bundles remaining af- ter the operation. Men undergoing bilateral nerve- sparing operations have a greater rate of return of erectile function than men undergoing unilateral nerve-sparing operations. In large contemporary series, 47% to 76% of patients regained their erec- tile function with preservation of both neurovas- cular bundles compared with 25% to 53% of pa- tients with preservation of a single nerve bundle. 1–3 When both neurovascular bundles are resected, very few patients can have spontaneous erections. 4 In patients who have a high risk of extracapsular tumor extension, wide resection of the prostate with excision of the neurovascular bundle can re- duce the risk of positive surgical margins and dis- ease recurrence. 5 However, sacrifice of the cavern- osal nerves is done at the expense of potency after surgery. Kim et al. 6,7 first reported the technique of bilateral interposition sural nerve grafts after radi- cal prostatectomy with bilateral cavernosal nerve resection and showed that the technique is techni- cally feasible and resulted in return of spontaneous erection in some cases. Of 23 patients, 6 (26%) were able to have medically unassisted intercourse and 6 (26%) had partial erections at 18 months. 8 The benefit of a unilateral interposition nerve graft is less obvious, because potency may be pre- served in up to one half of patients with unilateral nerve resection without a nerve graft. We studied a group of patients who underwent unilateral nerve- sparing radical prostatectomy combined with sural nerve grafting of the cut cavernosal nerve. By com- From the Departments of Urology and Neurosurgery, University of Washington School of Medicine; and Veterans Affairs Puget Sound Health Care System, Seattle, Washington Reprint requests: Claire C. Yang, M.D., Department of Urol- ogy, University of Washington School of Medicine, Box 356510, Seattle, WA 98195. E-mail: cyang@u.washington.edu Submitted: March 9, 2006, accepted (with revisions): August 11, 2006 ADULT UROLOGY © 2006 ELSEVIER INC. 0090-4295/06/$32.00 1290 ALL RIGHTS RESERVED doi:10.1016/j.urology.2006.08.1064