A randomized phase 3 study of intraoperative cavernous nerve stimulation with penile tumescence monitoring to improve nerve sparing during radical prostatectomy.

PURPOSE We determine if mapping of the cavernous nerve during radical prostatectomy using intraoperative cavernous nerve stimulation with tumescence monitoring results in improved erectile potency compared to conventional nerve sparing. MATERIALS AND METHODS A prospective, randomized, single blinded study was performed on 61 patients at 6 centers. Patients had elected to undergo nerve sparing prostatectomy and had normal preoperative erectile function documented by the Sexual Function Inventory Questionnaire (SFIQ) and RigiScan parallel testing. Patients were randomized between conventional nerve sparing and nerve sparing assisted by the CaverMap Surgical Aid. paragraph sign In all patients neural continuity was assessed immediately after prostate removal by proximal cavernous nerve stimulation. All patients were blinded according to their allocation cohort. RESULTS At 1 year there was substantial improvement in erectile function in the CaverMap group as measured by RigiScan. This group had a mean of 15. 9 minutes of greater than 60% nocturnal tumescence compared to 2.1 minutes in the conventional nerve sparing group (p <0.024). By SFIQ there was a nonsignificant trend to improved potency in the CaverMap group (71% versus 62%, p = 0.17). Of patients who had bilateral, unilateral and no response to stimulation after resection erectile function assessed by SFIQ recovered in 68%, 27% and 0%, respectively (p = 0.016). CONCLUSIONS CaverMap assisted prostatectomy led to improved erectile function as assessed by RigiScan testing with no associated adverse events. A response to stimulation immediately after removal of the prostate accurately predicted return of erectile function.

[1]  W. D. de Groat,et al.  Electrophysiological study of neural activity in penile nerve of the rat. , 1988, The American journal of physiology.

[2]  P. Scardino,et al.  Sildenafil citrate after radical retropubic prostatectomy. , 1999, The Journal of urology.

[3]  M. Bagshaw.  Effect of combined transient androgen deprivation and irradiation following radical prostatectomy for prostatic cancer. , 1999, The Prostate.

[4]  C. Bennett,et al.  Sexual dysfunction and electroejaculation in men with spinal cord injury: review. , 1988, The Journal of urology.

[5]  L. Bégin,et al.  Neurogenic erectile dysfunction: the course of nicotinamide adenine dinucleotide phosphate diaphorase-positive nerve fibers on the surface of the prostate. , 1996, Urology.

[6]  U. Michl,et al.  Is intraoperative electrostimulation of erectile nerves possible? , 1999, The Journal of urology.

[7]  J. Robinson,et al.  Erectile functioning of men treated for prostate carcinoma , 1997, Cancer.

[8]  A. G. Johnson,et al.  Surgery as a placebo , 1994, The Lancet.

[9]  A. Agarwal,et al.  Treatment of erectile dysfunction after radical prostatectomy with sildenafil citrate (Viagra). , 1999, Urology.

[10]  A. Melman,et al.  Intracavernous pressure responses to physical and electrical stimulation of the cavernous nerve in rats. , 1998, Urology.

[11]  T. Lue,et al.  Electrostimulation and penile erection. , 1985, Urologia internationalis.

[12]  P. Carroll,et al.  Intraoperative electrostimulation of the cavernous nerve: technique, results and limitations. , 1995, The Journal of urology.

[13]  T. Lue,et al.  Spinal anesthesia and electroerection in dogs and monkeys. , 1989, The Journal of urology.

[14]  P. Walsh,et al.  Sexual function following radical prostatectomy: influence of preservation of neurovascular bundles. , 1991, The Journal of urology.

[15]  J H Wasson,et al.  A structured literature review of treatment for localized prostate cancer. Prostate Disease Patient Outcome Research Team. , 1993, Archives of family medicine.

[16]  C. Carati,et al.  Autonomic control and vascular changes during penile erection in monkeys. , 1988, British journal of urology.

[17]  L. Klotz,et al.  Early experience with intraoperative cavernous nerve stimulation with penile tumescence monitoring to improve nerve sparing during radical prostatectomy. , 1999, Urology.