Grades of Robotic Nerve Sparing – AUA 2008 Award Winning Video from nycrobotics on Vimeo.

Technique of traction-free nerve-sparing robotic prostatectomy: delicate tissue handling by real-time penile oxygen monitoring.

Sexual dysfunction is the most common long-term adverse effect of a Robotic prostatectomy. Published literature has reported that anywhere between 30% and 85% of men are incapable of an erection sufficient for penetration following RP. It is postulated that erectile dysfunction results from damage to the nerves during surgery that cause histologic changes within the penis. ED also results from the loss of oxygen to the penis due to the restriction of blood flow to this area during surgery. Dr. Ash Tewari of Weill Cornell Medical College Prostate Cancer Institute hypothesized that if he could monitor tissue oxygenation in the neural tissue and penis, it may serve as a surrogate for significant traction on this important tissue. He also hypothesized that real-time intraoperative feedback regarding tissue oxygenation levels could aid surgeons in making slight alterations in surgical technique. Between May 2008 and July 2008, 64 patients were enrolled in this study (group 1). Following sterilization, the Odissey Tissue Oximeter probe was placed on the shaft of the penis, 2 cm from its base. The patient underwent continuous penile tissue saturation monitoring during surgery. Surgical dissection was altered whenever the oxygen saturation alarm went off until it was restored to ≥85%. In addition, 192 patients, matched for age, preoperative prostate-specific antigen, clinical stage, baseline sexual function, Charlson comorbidity index and nerve-sparing status operated between October 2007 and July 2008, formed the control group (group 2). These patients did not have any intraoperative tissue oxygenation monitoring. Our results were as follows: A significantly higher percentage of group 1 patients with bilateral nerve sparing had no ED compared with group 2 patients at 6 weeks (24.5% vs. 10.4%; P=.014) and 52 weeks (83.7% vs. 68%; P=.029). Overall, 93.9% of patients in study group had Sexual Health Inventory for Men (SHIM) score of ≥17 (mild to no ED) at 1 year compared with 78.4% of patients in the control group. We conclude that avoidance of stress to the penile tissues, aided by intraoperative penile oxygenation monitoring, may help surgeons improve their technique and thus functional outcomes in patients.

This study appeared in the International Journal of Impotence Research (2012). The abstract can be found here.

Matthieu Durand and Prof. Jean Amiel (L to R)

The European Association of Urology is holding its annual meeting in Paris this week. Our team has won first prize for best oncology abstract for the work presented in “Real-time, in vivo multiphoton microscopy imaging is a promising tool to identify prostate tissue during rat survival surgery.” This work was presented by Matthieu Durand who spent a year working at Cornell in New York. The full abstract can be found here and is reproduced below.

Multiphoton microscopy is a novel imaging modality that can differentiate various structures while performing prostate cancer surgery. This technology has the potential to reduce morbidity and complications during robotic prostate surgery.
Real-time, in vivo multiphoton microscopy imaging is a promising tool to identify prostate tissue during rat survival surgery
Durand, M.1, Aggarwal, A.2, Robinson, B.3, Srivastava, A.4, Sooriakumaran, P.4, Mtui, J.4, Brooks, D.4, Flomenbaum, D.4, Sterling, J.2, Mukherjee, S.2, Leung, R.4, Tewari, A.K.4
1Academic Hospital of Nice, Dept. of Urology, Nice, France, 2Weill Medical College of Cornell University, Dept. of Biochemistry, New York, United States of America, 3Weill Medical College of Cornell University, Dept. of Surgical Pathology, New York, United States of America, 4Weill Medical College of Cornell University, Dept. of Urology, New York, United States of America
Introduction & Objectives

Extraprostatic extension of prostate cancer is a microscopic phenomenon; therefore, it is not possible to differentiate cancerous cells from nerves during surgery. This can result in the incomplete removal of the cancer and/or postoperative impotence due to damage or excision of the nerves. In vivo multiphoton microscopy (MPM) is a novel technology that has shown promise in visualizing prostatic structures and adjacent nerves in an ex vivo setting. We investigated its role in an animal model, to discover whether it could be used in an in vivo setting.
Material & Methods

We used a custom-built MPM, consisting of an Olympus BX61WI upright frame and a modified Bio-Rad MRC 1024 scanhead. We used Sprague Dawley rat models, ex vivo and then in vivo for in-situ MPM imaging to assess its ability for identifying the anatomy of the prostatic tissue; we also examined the imaged tissue for signs of phototoxicity. A cocktail of ketamine and xylazyne was used as general anesthesia to keep the rat asleep and decrease body movement during imaging. Open surgical exposure of the prostate was performed to image the right prostatic lobe and the left lobe was used as an internal control. After image acquisition, the rat’s abdominal cavity was closed and the rat removed from the stage back to the husbandry unit for recovery. The rat was monitored for at least 15 days to check for signs of distress. Finally, the rat was euthanized and the whole prostate was processed for histological analysis to look for phototoxicity effects and to provide correlation between MPM ‘virtual’ histology and the gold standard.
Results

MPM was correctly able to identify anatomical structures of the rat prostatic tissue, as seen in figure 1. No tissue damage was observed either during imaging, or in the histopathology slides prepared from the imaged specimens.
Conclusions

Real-time, MPM imaging is feasible and safe without damaging tissue structures or being life-threatening in rat models. This novel technology may in the future be translated to human subjects via intra-operative use of a multiphoton endoscope currently being developed by our collaborators.

Patients’ satisfaction with overall sexual experience is substantially influenced by orgasm. As a result, variations in orgasm can lead to reductions in physical and emotional satisfaction.  Orgasmic dysfunction, which can take the form of decreased intensity, absence or dysorgasmia, is a common complication associated with radical prostatectomy. Although studies have shown a reduction in orgasmic function after retropubic radical prostatectomy, there is a dearth of information studying the effects of robotic assisted radical prostatectomy on orgasmic function.  In order to address this lack of data, Dr. Ash Tewari investigated the orgasmic outcomes in patients undergoing robotic assisted laparoscopic radical prostatectomy (RALP) and the effects of age and nerve sparing on these outcomes.  This study appeared in the February issue of British Journal of Urology International.

Between January 2005 and June 2007, 708 patients underwent RALP at our institution.  Out of 708, 444 patients fulfilled our criteria for eligibility, preoperatively potent and able to achieve orgasm. Potency was defined as achieving erections sufficient for vaginal intercourse.  Of those 444 patients, 36 were lost to follow up, thus the final cohort consisted of 408 eligible patients.  These patients completed health questionnaire’s pre operatively and then at regular intervals after surgery, specifically evaluating their post orgasmic function. Of men aged ≤60 years, 88.4% (198/224) were able to achieve orgasm postoperatively in comparison to 82.6% (152/184) of older men (P < 0.001). Of patients who received bilateral nerve sparing (BNS) during surgery, 273/301 (90.7%) were able to achieve orgasm postoperatively compared with 46/56 (82.1%) patients who received unilateral nerve sparing and 31/51 (60.8%) men who received non-nerve sparing surgery (P <0.001).  In men ≤60 years who also underwent BNS, decreased sensation of orgasm was present in 3.2% of men, and postoperative orgasmic rates were significantly better than men ≤60 years who underwent unilateral or no nerve sparing (92.9% vs. 83.3% vs. 65.4%, respectively; P <0.001). Potency rates were also significantly higher in men ≤60 years and in those who underwent BNS.

Our results suggest that age and nerve sparing influence recovery of orgasm and erectile function after RALP and that men ≤60 years old and those who undergo BNS are most likely to maintain normal sexual function.

Dr. Ash Tewari is an expert in robotic prostatectomy for the treatment of prostate cancer. He has performed over 3500 robotic prostate cancer surgeries.

The Institute for Prostate Cancer at the Weill Cornell Medical College Department of Urology is delighted to invite you to the Inaugural Prostate Cancer Symposium on May 10 – 12, 2011. This multidisciplinary meeting will bring together over 70 experts from across the globe, aimed toward initiating advances in prostate cancer care.

Registration is now open. Visit our symposium website.