Intraoperative Nerve Monitoring During Robotic-assisted Radical Prostatectomy

Can Intraoperative Nerve Monitoring Predict and Improve Functional Outcomes After Robotic-assisted Radical Prostatectomy

The purpose of this study is to evaluate whether the use of intraoperative nerve monitoring during robotic-assisted radical prostatectomy (RARP) can predict and improve post-surgery urinary continence and erectile function.

Study design: This is a single center, randomized, single blinded, prospective, clinical trial. The study population will comprise of 100 men that will undergo either a non-nerve sparring or unilateral-nerve sparring RARP. This means that the preoperative evaluation has suggested that it will not be possible to preserve the cavernous parasympathetic nerves lying in the fascia on either side of the prostate gland during surgery (called bilateral-nerve sparring). Despite the term, non-nerve sparring surgery, the surgeon will still attempt to preserve the somatic fibers of the pudendal nerve as best possible. However, due to the extent of cancer tissue the surgeon will generally need to operate closer to the pudendal nerve then when performing bilateral-nerve sparring surgery. So, the somatic fibers of the pudendal nerve are more likely to be severed. The same is the case on one side when performing unilateral surgery. The treatment group will consist of 50 subjects that will undergo nerve monitoring during RARP. Results will be compared to a control cohort consisting of 50 patients that will undergo contemporary RARP. Aside from the usage of nerve monitoring in the intervention-group, all procedures and care from admission to the hospital through discharge will be standard of care for subjects in both the control and Intervention-group. Baseline evaluation and collection of data: Patients will be screened for eligibility on the phone, and if eligible and they accept they will be scheduled to a visit at the hospital where the following data will be registered for all participants prior to surgery: Age at time of surgery Known co-morbidity Body Mass Index (BMI) Medicine status Smoking Partner status Level of education Employment Clinical status Clinical stage (cT-staging) Gleason score Prostate specific antigen (PSA) Prior to surgery participants will also have answered the questionnaires listed either prior to or during the first visit and have undergone an MRI and the bulbocavernosus-reflex test: ICIQ (International Consultation on Incontinence Questionnaire) form about incontinence symptoms Danish Prostate Symptom Score (DAN-PSS) International Prostate Symptom Score (IPSS) International Index of Erectile Function (IIEF) score Erection Hardness Scale (EHS) score Presence or absence of bulbocavernosus-reflex. The physician test for this by shortly squeezing the penis while observing if the urethra retracts or the anal sphincter contracts. The test is not painful and only takes a few seconds. Magnetic Resonance Imaging (MRI) scan with measurements of the urethral length and width, and prostate volume along with other specific anatomical structures in relation to the urethra. Contrast agents will not be applied. Intraoperative data: Contraction of the sphincter musculature during stimulation via the nerve monitoring system before removal of the prostate gland Contraction of the sphincter musculature during stimulation via the nerve monitoring system after removal of the prostate gland. Blood loss Non- or unilateral nerve sparring Lymph node dissection Total surgical time Sphincter lesion The surgeon's subjective prediction whether the patient will return to continence postoperatively During the procedure, through discharge and before follow-up regime begins, the following data points will be collected: Time to removal of catheter Leakage of the anastomosis Stricture. Other adverse effects Pathologic cancer stage (pT-stage) Pathologic Gleason score Status of surgical margins Follow-up evaluation. Subjects will be evaluated 14 days after catheter removal and at standard clinical controls at 3, 6 and 12 months. The following questionnaires are answered at every visit: International consultation on Incontinence Questionnaire (ICIQ) for incontinence, Danish Prostate Symptom Score (DAN-PSS) International Prostate Symptom Score (IPSS) International Index of Erectile Function (IIEF) and Erection Hardness Scale (EHS). During the last 3 visits subjects also answers a fluid intake/output questionnaire and hand in the results of a 24-hour pad test. In addition to the questionnaires the patients will also undergo an MRI and a bulbocavernosus reflex test 12 months postoperative.

Urinary incontinence, Prostate cancer, Erectile dysfunction, Functional outcome, Robotic prostatectomy, Prostatectomy, Urethral sphincter

Patients that undergo robotic-assisted radical prostatectomy with the use intraoperative nerve monitoring, via electromyography, to identify the exact location of the somatic fibers in the pelvic nerves that seem crucial for urinary continence control and erectile function

Intraoperative nerve monitoring, via electromyography, enables real-time identification of the location of the somatic fibers in the pelvic nerves that seem crucial for urinary continence control and erectile function.

Difference in total International consultation on incontinence questionnaire (ICIQ)-score between the 2 groups after a follow-up of 1 year. ICIQ is a self-reported survey and screening tool for incontinence. It consists of 3 questions regarding symptoms in the past 4 week, with an overall 0-21 score, where greater values indicate increased severity. Question 1 scores from 0-5, question 2 scores either 0,2,4 or 6 and question 3 scores from 0-10. Only the total score is evaluated. Furthermore there is 1 self-diagnostic question.

Difference in erection rates and sexual activity between the 2 groups after 12 months. Sexual activity defined as yes to the question "Within the last 3 months, have you been sexually active and attempted intercourse?" Erection is defined as a score of at least 17 on the IIEF-5 form and or a score of a least 3 on the EHS form with the use of either no assistance phosphodiesterase 5 inhibitors

Nerve function prior to removal of the prostate correlated to patient's preoperative urinary function

Nerve function prior to removal of the prostate correlated to patient's preoperative erectile function

Inclusion Criteria: Patients that are planned to undergo either non-nerve or unilateral nerve sparring surgery. Patients that deemed able to understand the protocol and to return for all the required post-treatment follow-up visits. Exclusion Criteria: Incontinence prior to surgery Diabetes Known neurological disease that can affect urinary/erectile function Condition with Pacemaker Previous pelvic trauma Previous pelvic surgery including transurethral resection of the prostate Previous pelvic radiation therapy