Cadaveric study of nerves supplying the membranous urethra

Erectile function, urinary continence and oncologic outcomes of neurovascular bundle sparing robot-assisted radical prostatectomy for high-risk prostate cancer: A systematic review and meta-analysis

Background

The nerve-sparing (NS) effect of robot-assisted radical prostatectomy (RARP) on patients with a high-risk prostate cancer remains unclear. The objective of this study was to compare the urinary continence, erectile function and oncology outcomes of the nerve-sparing and non-nerve-sparing (NNS) group during RARP surgeries.

Methods

We systematically searched databases including PubMed, Embase, Cochrane Library and Web of Science to identify relevant studies published in English up to December 2022. Newcastle-Ottawa Scale (NOS) was used as a quality evaluation tool to evaluate the quality of the literature parameters involved, including urinary continence, erectile function and oncologic outcomes, which were compared using the Stata 15.1 software (StataSE, USA).

Results

A total of 8 cohort studies involving 2499 patients were included. A meta-analysis of results showed that the NS group was beneficial to the recovery of urinary continence (RR 0.46, 95%CI 0.22, 0.96; p=0.045<0.05) and erectile function (RR 0.32, 95%CI 0.16, 0.63; p=0.001<0.05) 12 months after surgeries, which showed a better oncological outcome (RR 1.31, 95%CI 1.01, 1.69; p=0.01<0.05).

Conclusions

The current study results indicate that intraoperative NS during RARP is beneficial to long-term postoperative functional recovery and tumor prognosis of patients with high-risk prostate cancers. Due to interstudy interferences, the results should be interpreted with caution.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022384647.

Optimizing Nerve Sparing in Robotic-Assisted Radical Prostatectomy: A Comparative Investigation of Traditional and Modified Endopelvic Fascia Preservation Techniques

Background

Prostate cancer (PCa) is the second most common cancer and the sixth leading cause of cancer-related mortality in men. In 2000, Abbou performed the first robot-assisted radical prostatectomy, and radical prostatectomy has developed rapidly. Robot-assisted radical prostatectomy (RARP) is a valuable therapeutic option for the management of localized Pca.

Objective

To present the functional outcome of robot-assisted laparoscopic radical prostatectomy using traditional and modified endopelvic fascia preservation methods in a single center in Vietnam.

Methods

We prospectively analyzed a series of 65 patients diagnosed with prostate cancer from 2020 to 2023. All of those were operated by DaVinci Si system robot-assisted laparoscopic prostatectomy. Twenties patients were applied with a modified nerve-sparing technique, intrafascial dissection, and lateral prostatic fascia preservation, leaving the lateral tissue, including the neurovascular bundle, untouched and covered. We used the traditional approach, intrafascial nerve-sparing with open endopelvic fascia and lateral prostatic fascia in 45 cases. Patients were followed up to 12 months to assess the continence and erectile function by using IIEF-5 and EPIC questionnaires.

Results

The study sample included 65 cases; the mean patient age was 64.21 ± 6.68, erection rate after surgery at six months in bilateral NS was 36.58% (15/41) in the traditional group, and 68.42% (13/19) in the modified group (p=0.028). The patient did not recover erectile ability in the group of elderly patients (>65 years old) and unilateral nerve-sparing group. The continence rate six months after surgery was 86.66 % in the conventional group and 85% in the modified group, with no significant difference between the two groups. In the potency group, the IIEF-5 score was 13 ± 4.9, and the EPIC-26 score was 62.20 ± 10.04. Erectile ability in the modified group was better than the traditional group at six months after surgery.

Conclusion

Our results showed better potency recovery in the modified group. These results should be tested in future research with randomized studies.

The effects of primary realignment or suprapubic cystostomy on prostatic displacement in patients with pelvic fracture urethral injury: a clinical study based on MR urethrography

BACKGROUND

To provide direct evidence of whether primary realignment (PR) or suprapubic cystostomy (SPC) had different effects on the prostatic displacement and prognosis in patients with pelvic fracture urethral injury who needed delay anastomotic urethroplasty based on Magnetic Resonance (MR) urethrography.

METHODS

We screened the urethral stenosis database of our single institution from January 2016 to June 2020. Patients who underwent delayed anastomotic urethroplasty with a preoperative MR urethrography and no treatment history of urethra were included. We compared the urethral gap length and prostatic displacement between the PR and SPC group based on MR urethrography. The terminal outcomes such as stenosis-free rate, urinary continence and erectile function were also analyzed between two groups.

RESULTS

66 patients were included in this retrospective study in which 36 were in PR group and 30 in SPC group. Mean follow-up time was 15.1 months (3-38 months). One and two patients experienced recurrence of stenosis after urethroplasty in two groups (p = 1.000). No difference of erectile dysfunction and urinary incontinence was found between two groups. Based on MR urethrography, the urethral gap length was 17.4 mm and 23.3 mm (p = 0.008) which presented a significant decrease in PR group. The superior prostatic displacement was similar in two groups (9.8 mm vs. 13.8 mm, p = 0.081). The numbers and distance of displacement on lateral aspect showed no difference, either. However, PR group had less anterior-posterior prostatic displacement (p = 0.005). Besides, the erectile function was significantly related to the lateral prostatic displacement (p = 0.030/0.047).

CONCLUSIONS

Based on MR urethrography, patients in PR group showed shorter urethral gap distance and slighter anterior-posterior prostatic displacement without extra erectile dysfunction or incontinence. Besides, patients' erectile function might be significantly related to the lateral prostatic displacement.

A randomised-controlled, prospective study on the effect of dorsal penile nerve block after TURP on catheter-related bladder discomfort and pain

PURPOSE

In the present study, the impact of penile nerve block (PNB) on postoperative pain and Catheter-Related Bladder Discomfort (CRBD) in the transurethral resection of prostate(TURP) patients were evaluated.

METHODS

Participants of the present study were selected from patients who performed TURP under spinal anaesthesia for benign prostatic hyperplasia (BPH) between January 2018 and July 2020. The present study was planned as a single-centre, randomised-controlled prospective study in which the patients were divided into two groups. Group 1 was administered Control (n:40), and Group 2 ultrasonography(USG) guided PNB (n:40). The patients were included in the Groups, respectively. Visual analogue scale (VAS) scores were questioned and recorded in order to evaluate the postoperative pain complaints of the patients after the operation. In addition, in order to evaluate the CRBD, VAS scores were questioned and recorded as 0th, 0-1th hour, 1st-2nd hour, 2nd-4th hour, 4th-8th hour, 8th-12th hour, and 12th-24th hour. In addition, postoperative pain and need for analgesic drug were recorded. Tramadol was given to patients with moderate to severe CRBD. The findings were compared between the Groups.

RESULTS

There was no statistical difference demographic and per-operative data between Group 1 and Group 2. The CRBD and pain-related VAS scores were significantly higher in Group 1 between the 0 and 8th hours. There was no difference between VAS scores in the postoperative 8-24th hours. In total 24 hours, Group 2's need for tramadol was significantly less than Group 1. On examining the factors affecting CRBD in the multivariate analysis, age, body mass index(BMI), prostate volume, operation time do not affect CRBD statistically, and only PNB reduces CRBD (P: .029). While less drug-related complications were observed in Group 2, no serious complications related to PNB were observed.

CONCLUSION

Penile nerve block is an effective method for the decrease pain and CRBD after urological surgery. It will also reduce the need for analgesics, and provide painless patients in the postoperative period.

Dorsal penile nerve block alleviates pain in men undergoing rigid cystoscopy: A single‐center, randomized, double‐blind, and placebo‐controlled trial

Objective

To assess the effectiveness and safety of dorsal penile nerve block (DPNB) compared with tetracaine gel in analgesia for men undergoing rigid cystoscopy.

Patients and methods

This study was conducted as a prospective, randomized, double‐blind, placebo‐controlled, and single‐center trial. Men undergoing diagnostic rigid cystoscopy were randomly allocated into one of three groups (n = 86 each): (1) tetracaine gel group (DPNB with saline), (2) DPNB group (DPNB with ropivacaine + plain lubricant), and (3) combination group (DPNB with ropivacaine + tetracaine gel). The primary outcome was visual analog scale (VAS) for pain at cystoscopic inspection of the external sphincter.

Results

VAS (median [interquartile]) at inspection of the external sphincter was significantly lower in both DPNB and combination groups than that in tetracaine gel group (4 [3–6] and 4 [3–5] vs 6 [5–7], P < .0001), with a 33% reduction of median VAS. Overall pain level during procedure was significantly alleviated in the DPNB and combination groups with more stabilized HR and MAP when compared with tetracaine gel group. No adverse events were observed during DPNB including penile hematoma, erection, local anesthetic toxicosis or incompletion of cystoscopy.

Conclusion

Our study suggests analgesia provided by DPNB with or without tetracaine gel instilled is superior to that provided by tetracaine gel alone in men undergoing diagnostic rigid cystoscopy.

Clinical Trials Registration

ClinicalTrials.gov registration number: NCT02502487.

Does instillation of lidocaine gel following flexible cystoscopy decrease the severity of post procedure symptoms? A randomised controlled trial assessing the efficacy of lidocaine gel post flexible cystoscopy

Objective

To assess whether instillation of lidocaine gel both before and after flexible cystoscopy is more effective at reducing post procedural symptoms than instillation of lidocaine gel pre flexible cystoscopy alone. We hypothesise that inadequate urethral dwell time and dilution of lidocaine gel by the irrigation fluid during flexible cystoscopy limits its anaesthetic efficacy. Only one other study has attempted to reduce bothersome urinary symptoms through an intervention after flexible cystoscopy.

Methods

This was a randomised controlled trial in which patients were randomised 1:1 to receive lidocaine gel pre and post flexible cystoscopy (treatment) or lidocaine gel pre flexible cystoscopy only (control). Patient-reported outcome measures were used to assess symptoms and quality of life prior to cystoscopy, on day 2 and day 7 post cystoscopy.

Result

Fifty patients were divided equally between the treatment and control groups. There were no significant differences in baseline characteristics between the groups (p = 1.000). An overall symptoms variable was measured, though no significant difference was found in the distribution of responses between the groups at baseline, 2 or 7 days after the flexible cystoscopy (p = 0.423, 0.651,0.735). In the treatment group, 1 patient (4.0%) presented to a doctor for review following flexible cystoscopy, and 4 patients (16.0%) presented in the control group (p = 0.349).

Conclusion

Initial study results suggest that post-operative lidocaine does not significantly limit the exacerbation of urinary symptoms following flexible cystoscopy; however, our results are not powered to detect a small difference. We do not recommend a change in practice based on our results.

Predictors of urinary toxicity with MRI-assisted radiosurgery for low-dose-rate prostate brachytherapy

PURPOSE

MRI-assisted radiosurgery (MARS) is a modern technique for prostate brachytherapy that provides superior soft tissue contrast. The purpose of this analysis was to evaluate treatment planning factors associated with urinary toxicity, particularly damage to the membranous urethra (MUL) and external urethral sphincter (EUS), after MARS.

MATERIAL AND METHODS

We retrospectively reviewed 227 patients treated with MARS. Comparisons were made between several factors including preimplantation length of the MUL and EUS dosimetric characteristics after implantation with longitudinal changes in American Urological Association (AUA) urinary symptom score.

RESULTS

Rates of grade 3 urinary incontinence and obstructive urinary symptoms were 4% and 2%. A piecewise mixed univariate model revealed that MUL and V₂₀₀, V₁₅₀, V₁₂₅, and D₅ to the EUS were all associated with increased rates of urinary toxicity over time. On univariate logistic regression, MUL >14.2 mm (odds ratio [OR] 2.03 per cm³, 95% confidence interval [CI] 1.10-3.77, p = 0.025), V₁₂₅ to the EUS (OR 3.21 cm³, 95% CI 1.18-8.71, p = 0.022), and use of the I-125 isotope (OR 3.45, 95% CI 1.55-7.70, p = 0.001) were associated with subacute urinary toxicity (i.e., that occurring at 4-8 months). Optimal dose-constraint limits to the EUS were determined to be V₂₀₀ < 0.04 cm³ (p = 0.002), V₁₅₀ < 0.12 cm³ (p = 0.041), V₁₂₅ < 0.45 cm³ (p = 0.033), D₃₀ < 160 Gy (p = 0.004), and D₅ < 218 Gy (p = 0.016).

CONCLUSIONS

MARS brachytherapy provides detailed anatomic information for treatment planning, implantation, and quality assurance. Overall rates of urinary toxicity are low; however, several dosimetric variables associated with the EUS were found to correlate with urinary toxicity.

Effect of Bladder Neck Preservation on Long-Term Urinary Continence after Robot-Assisted Laparoscopic Prostatectomy: A Systematic Review and Meta-Analysis

This study aimed to evaluate the effect of bladder neck preservation (BNP) on long-term urinary continence after robot-assisted laparoscopic prostatectomy (RALP). We systematically searched the PubMed, Embase, and Cochrane Library databases to identify studies that assessed the difference in urinary continence and oncologic outcomes between patients who underwent RALP with BNP and those who underwent RALP without BNP. Four trials (1880 cases with BNP, 727 controls without BNP) were considered suitable for meta-analysis. BNP was associated with significantly better urinary continence outcomes at 3–4 months (odds ratio (OR), 2.88; 95% confidence interval (CI), 1.52–5.48; p = 0.001), 12 months (OR, 2.03; 95% CI, 1.10–3.74; p = 0.02), and 24 months (OR, 3.23; 95% CI, 1.13–9.20; p = 0.03) after RALP. There was no difference in the rate of overall positive surgical margin (PSM) (OR, 1.00; 95% CI, 0.72–1.39; p = 0.99) and that of PSM at the prostate base (OR, 0.49; 95% CI, 0.21–1.13; p = 0.09) between the two groups. The BNP technique during RALP leads to early return of urinary continence and long-term urinary continence without compromising the oncologic outcomes.

Reconstruction of Membranous Urethral Strictures

PURPOSE OF REVIEW

Due to the proximity of the rhabdosphincter and cavernous nerves to the membranous urethra, reconstruction of membranous urethral stricture implies a risk of urinary incontinence and erectile dysfunction. To avoid these complications, endoscopic management of membranous urethral strictures is traditionally favored, and bulboprostatic anastomosis is reserved as the main classical approach for open reconstruction of recalcitrant membranous urethral stricture. The preference for the anastomotic urethroplasty among reconstructive urologists is likely influenced by the familiarity and experience with trauma-related injuries. We review the literature focusing on the anatomy of membranous urethra and on the evolution of treatments for membranous urethral strictures.

RECENT FINDINGS

Non-traumatic strictures affecting bulbomembranous urethra are typically sequelae of instrumentation, transurethral resection of the prostate, prostate cancer treatment, and pelvic irradiation. Being a different entity from trauma-related injuries where urethra is not in continuity, a new understanding of membranous urethral anatomy is necessary for the development of novel reconstruction techniques. Although efficacious and durable to achieve urethral patency, classical bulboprostatic anastomosis carries a risk of de-novo incontinence and impotence. Newer and relatively less invasive reconstructive alternatives include bulbar vessel-sparing intra-sphincteric bulboprostatic anastomosis and buccal mucosa graft augmented membranous urethroplasty techniques. The accumulated experience with these techniques is relatively scarce, but several published series present promising results. These approaches are especially indicated in patients with previous transurethral resection of the prostate in which sparing of rhabdosphincter and the cavernous nerves is important in attempt to preserve continence and potency. Additionally, introduction of buccal mucosa onlay grafts could be especially beneficial in radiation-induced strictures to avoid transection of the sphincter in continent patients, and to preserve the blood supply to the urethra for incontinent patients who will require artificial urinary sphincter placement. The evidence regarding erectile functional outcomes is less solid and this item should be furtherly investigated.

Surgical Techniques to Optimize Early Urinary Continence Recovery Post Robot Assisted Radical Prostatectomy for Prostate Cancer

Purpose of Review

A variety of different surgical techniques are thought to impact on urinary continence (UC) recovery in patients undergoing robot assisted radical prostatectomy (RARP) for prostate cancer. Herein, we review current evidence and propose a composite evidence-based technique to optimize UC recovery after RARP.

Recent Findings

A literature search on studies reporting on surgical techniques to improve early continence recovery post robotic prostatectomy was conducted on PubMed and EMBASE. The available data from studies ranging from randomized control trials to retrospective cohort studies suggest that minimizing damage to the internal and external urinary sphincters and their neural supply, maximal sparing of urethral length, creating a secure vesicourethral anastomosis, and providing anterior and posterior myo- fascio-ligamentous support to the anastomosis can improve early UC recovery post RARP.

Summary

A composite evidence-based surgical technique incorporating the above principles could optimize early UC recovery post RARP. Evidence from randomized studies is required to prove benefit.

Efficacy of pudendal nerve block for alleviation of catheter-related bladder discomfort in male patients undergoing lower urinary tract surgeries: A randomized, controlled, double-blind trial

BACKGROUND

Catheter-related bladder discomfort (CRBD) to an indwelling urinary catheter is defined as a painful urethral discomfort, resistant to conventional opioid therapy, decreasing the quality of postoperative recovery. According to anatomy, the branches of sacral somatic nerves form the afferent nerves of the urethra and bladder triangle, which deriving from the ventral rami of the second to fourth sacral spinal nerves, innervating the urethral muscles and sphincter of the perineum and pelvic floor; as well as providing sensation to the penis and clitoris in males and females, which including the urethra and bladder triangle. Based on this theoretical knowledge, we formed a hypothesis that CRBD could be prevented by pudendal nerve block.

OBJECTIVE

To evaluate if bilateral nerve stimulator-guided pudendal nerve block could relieve CRBD through urethra discomfort alleviation.

DESIGN AND SETTING

Single-center randomized parallel controlled, double blind trial conducted at West China Hospital, Sichuan University, China.

PARTICIPANTS

One hundred and eighty 2 male adult patients under general anesthesia undergoing elective trans-urethral resection of prostate (TURP) or trans-urethral resection of bladder tumor (TURBT). Around 4 out of 182 were excluded, 178 patients were randomly allocated into pudendal and control groups, using computer-generated randomized numbers in a sealed envelope method. A total of 175 patients completed the study.

INTERVENTION

Pudendal group received general anesthesia along with nerve-stimulator-guided bilateral pudendal nerve block and control group received general anesthesia only.

MAIN OUTCOME MEASURES

Incidence and severity of CRBD; and postoperative VAS score of pain.

RESULTS

CRBD incidences were significantly lower in pudendal group at 30 minutes (63% vs 82%, P = .004), 2 hours (64% vs 90%, P < .000), 8 hours (58% vs 79%, P = .003) and 12 hours (52% vs 69%, P = .028) also significantly lower incidence of moderate to severe CRBD in pudendal group at 30 minutes (29% vs 57%, P < .001), 2 hours (22% vs 55%, P < .000), 8 hours (8% vs 27%, P = .001) and 12 hours (6% vs 16%, P = .035) postoperatively. The postoperative pain score in pudendal group was lower at 30 minutes (P = .003), 2 hours (P < .001), 8 hours (P < .001), and 12 hours (P < .001), with lower heart rate and mean blood pressure. One patient complained about weakness in levator ani muscle.

CONCLUSION

General anesthesia along with bilateral pudendal nerve block decreased the incidence and severity of CRBD for the first 12 hours postoperatively.

The impact of nerve-sparing robot-assisted radical prostatectomy on lower urinary tract function: Prospective assessment of patient-reported outcomes and frequency volume charts

AIMS

To elucidate the effects of a nerve-sparing (NS) procedure on lower urinary tract symptoms (LUTS) and urinary function after robot-assisted radical prostatectomy (RARP), the associations between the NS procedure and LUTS and urinary function were investigated.

METHODS

The participants in this study were 200 consecutive patients who underwent RARP. These patients were categorized into unilateral and bilateral NS groups and the non-NS group. The International Prostate Symptom Score (IPSS), quality of life (QOL) index, frequency-volume chart, uroflowmetry, 1-h pad test, and the 5-item International Index of Erectile Function (IIEF-5) questionnaire were evaluated before and after RARP.

RESULTS

The total IPSS score was significantly lower in the unilateral (P = 0.03) and bilateral NS groups (P = 0.03) than in the non-NS group after RARP. Diurnal maximum voided volume (MVV) values were significantly greater in the bilateral NS group than in the non-NS group after RARP (P = 0.002). Nocturnal frequency was significantly decreased in the unilateral NS group than in the non-NS group after RARP (3 months P = 0.01, 12 months P = 0.01). Erectile function was significantly better in both the unilateral NS group (P < 0.0001) and the bilateral NS group (P = 0.02) than in the non-NS group 12 months after RARP.

CONCLUSIONS

The NS procedure in RARP has the possibility to improve not only erectile function, but also LUTS, owing to both the increase of MVV and the decrease of nocturia. Therefore, the NS procedure is also recommended from the viewpoint of early improvement of LUTS and lower urinary tract dysfunction after RARP.

Recovery of urinary continence after radical prostatectomy

INTRODUCTION

In the era of minimally-invasive surgery, urinary incontinence (UI) after radical prostatectomy (RP) still represents a troublesome issue for a considerable rate of patients. Factors associated with the risk of post-RP UI, need to be carefully assessed throughout the overall clinical management process thus including the pre-operative, intra-operative and post-operative setting.

AREAS COVERED

This review analyses current published evidences regarding clinical and surgical aspects associated with urinary continence (UC) recovery after RP. A careful evaluation of patient's clinical characteristics should be carried out before surgery in order to properly counsel the patients regarding the risk of UI. In the last two decades, the advent of robotic surgery has led to an overall improvement of functional outcomes after RP, thanks to the development of different surgical strategies based on either the 'preservation' or the 'reconstruction' of the anatomical elements responsible for urinary continence. Finally, several therapeutic strategies including either a conservative approach, or pharmacological and surgical treatments, should be carefully considered for the post-operative management of UI. Expert commentary: A comprehensive pre-operative patient's clinical assessment, along with a proper and well-conducted surgical procedure and an effective post-operative care management are essential element to achieve a high probability of UC recovery.

Dorsal penile nerve block for rigid cystoscopy in men: study protocol for a randomized controlled trial

Background

Pain is common in men undergoing rigid cystoscopy. Even with the application of a lubricant containing 2 % lidocaine, about 76 % of men suffer from mild to severe pain when undergoing rigid cystoscopy. The most painful part of the procedure for men is when the cystoscope passes through the membranous urethra. Song et al. (Neurourol Urodyn 29:592–5, 2010) did autopsies on males and found that the dorsal nerve of the penis (DNP), the terminal branch of the pudendal nerve, innervates the membranous urethra in 53.3 % of specimens. In addition, the urethral mucosa has branches of innervated DNP. Dorsal penile nerve block (DPNB) is usually used for circumcision in children, and it has been shown to provide effective analgesia for penile surgeries. In this study, we hypothesized that DPNB could reduce the overall pain level in men during rigid cystoscopy.

Methods/design

The trial is a prospective, randomized, double-blind, placebo-controlled, single-center trial to evaluate the effectiveness and safety of DPNB in analgesia for men undergoing rigid cystoscopy. Participants will be enrolled and randomly allocated into one of three groups according to the different analgesia regimens: 1) tetracaine gel group (DPNB with saline), 2) DPNB group (DPNB with ropivacaine plus plain lubricant), 3) combination group (DPNB with ropivacaine plus tetracaine gel). The primary outcome of this study is the visual analog scale (VAS, 0–10) for pain at cystoscopic inspection of the external sphincter. VAS scores evaluated at other time points serve as secondary outcomes. Vital signs are secondary outcomes that address the discomfort and pain during the procedure. Furthermore, the incidence of adverse events as secondary outcomes will also be recorded for evaluation of the safety of DPNB in rigid cystoscopy. Clinical assessments will be evaluated prior to DPNB, at administration of the lubricant gel, at cystoscopic inspection of the penile and bulbar urethra, external sphincter, prostate, and bladder, as well as at withdrawal of the cystoscope.

Discussion

This research will determine the effectiveness and safety of DPNB in men undergoing rigid cystoscopy. The results of this trial may have important implications for exploring the role of DPNB in analgesia for cystoscopy in men.

Trial registration

ClinicalTrials.gov identifier NCT02502487 (6 Jul 2015).

A Critical Analysis of the Current Knowledge of Surgical Anatomy of the Prostate Related to Optimisation of Cancer Control and Preservation of Continence and Erection in Candidates for Radical Prostatectomy: An Update

CONTEXT

In 2010, we published a review summarising the available literature on surgical anatomy of the prostate and adjacent structures involved in cancer control and the functional outcome of prostatectomy.

OBJECTIVE

To provide an update based on new literature to help the surgeon improve oncologic and surgical outcomes of radical prostatectomy (RP).

EVIDENCE ACQUISITION

We searched the PubMed database using the keywords radical prostatectomy, anatomy, neurovascular bundle, nerve, fascia, pelvis, sphincter, urethra, urinary continence, and erectile function. Relevant articles and textbook chapters published since the last review were critically reviewed, analysed, and summarised. Moreover, we integrated aspects that were not addressed in the last review into this update.

EVIDENCE SYNTHESIS

We found new evidence for several topics. Up to 40% of the cross-sectional surface area of the urethral sphincter tissue is laterally overlapped by the dorsal vascular complex and might be injured during en bloc ligation. Denonvilliers fascia is fused with the base of the prostate in a horizontal fashion dorsally/caudally of the seminal vesicles, requiring sharp detachment when preserved. During extended pelvic lymph node dissection, the erectile nerves are at risk in the presacral and internal iliac area. Dissection planes for nerve sparing can be graded according to the amount of tissue left on the prostate as a safety margin against positive surgical margins. Vascular structures can serve as landmarks. The urethral sphincter and its length after RP are influenced by the shape of the apex. Taking this shape into account allows preservation of additional sphincter length with improved postoperative continence.

CONCLUSIONS

This update provides additional, detailed information about the surgical anatomy of the prostate and adjacent tissues involved in RP. This anatomy remains complex and widely variable. These details facilitate surgical orientation and dissection during RP and ideally should translate into improved outcomes.

PATIENT SUMMARY

Based on recent anatomic findings regarding the prostate and its surrounding tissue, the urologist can individualise the dissection during RP according to cancer and patient characteristics to improve oncologic and functional results at the same time.

Preservation of the neurovascular bundles is associated with improved time to continence after radical prostatectomy but not long-term continence rates: results of a systematic review and meta-analysis

CONTEXT

The aetiology of urinary incontinence following radical prostatectomy (RP) is incompletely understood. In particular, it is unclear whether there is a relationship between neurovascular bundle (NVB) sparing and post-RP urinary continence.

OBJECTIVE

To review systematically the association of NVB sparing in RP with postoperative urinary continence outcomes and synthesise the results in a meta-analysis.

EVIDENCE ACQUISITION

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement. PubMed, Medline, and Cochrane Central Register of Controlled Trials were searched (December 2013), yielding 3413 unique records. A total of 27 longitudinal cohort studies were selected for inclusion. Studies were evaluated using a predefined criteria adapted from the Cochrane Tool to Assess Risk of Bias in Cohort Studies.

EVIDENCE SYNTHESIS

Data from 13 749 participants in 27 studies were synthesised in a meta-analysis. An assessment of the study methodology revealed a high risk of bias due to differences in baseline characteristics, outcome assessment, and the likely presence of unreported confounding factors such as meticulous apical dissection. Meta-analysis demonstrated that nerve sparing (NS) compared with non-nerve sparing (NNS) resulted in improved early urinary continence rates up to 6 mo postoperatively. Beyond this time, no significant difference was observed. This effect was seen most clearly for bilateral NS compared with NNS. A sensitivity analysis of prospective cohort studies revealed consistent results.

CONCLUSIONS

This analysis demonstrates an association between NS and improved urinary continence outcomes up to 6 mo postoperatively. NS in men with poor preoperative erectile function should be considered in the context of oncologic risk stratification because it may improve time to continence recovery. The underlying cause of the relationship between NS and continence is unknown. It may represent preservation of the intrapelvic somatic nerves supplying the rhabdosphincter or the influence of other confounding factors. Future research should be directed towards improving understanding of the anatomy of urinary continence and the pathophysiology of post-RP incontinence.

PATIENT SUMMARY

We found that avoiding damage to the nerves around the prostate improves urinary continence in the first 6 mo after surgery. After this time, there is no difference in continence between men who had these nerves removed and those who had them saved. This finding could be due to a true effect of saving these nerves or to a number of other factors affecting the research.

Nerve-sparing Surgery Technique, Not the Preservation of the Neurovascular Bundles, Leads to Improved Long-term Continence Rates After Radical Prostatectomy

BACKGROUND

The effect of preservation of neurovascular bundles (NVBs) during radical prostatectomy (RP) on continence remains controversial.

OBJECTIVE

To analyze if the differing surgical techniques of nerve-sparing (NS) versus non-nerve-sparing (NNS) RP and not the preservation of the NVB itself may be responsible for differences in continence rates.

DESIGN, SETTING, AND PARTICIPANTS

A total of 18 427 men who underwent RP from 2002 to 2014 in a single high-volume center were analyzed retrospectively. Patients with bilateral NS RP, with primary NNS RP, and with bilateral secondary resection of the NVBs for positive frozen-section results after an initial bilateral nerve sparing (secNNS) RP were studied.

INTERVENTION

NS, NNS, or secNNS RP.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Multivariable and propensity score matched analyses adjusting for age, prostate volume, and year of surgery were performed to assess differences in continence rates after RP. Continence was defined as the use of no or one safety pad per day.

RESULTS AND LIMITATIONS

Post-RP urinary continence rates at 1 wk, 3 mo, and 12 mo were 59.8%, 76.2%, 85.4% in the NS group, 39.5%, 59.5%, and 87.0% in the secNNS group, and 29.1%, 52.8%, and 70.5% in the NNS group. Continence rates at 12 mo after surgery did not differ significantly between patients who had bilateral NS and patients who had resection of both NVBs after an initial nerve-sparing technique (secNNS). In contrast, when comparing the NNS study groups with initial NNS versus secNNS, the latter group had significantly higher continence rates after 12 mo.

CONCLUSIONS

Our results indicate that the meticulous apical dissection associated with the NS RP technique rather than the preservation of the NVBs itself may have a positive impact on long-term urinary continence rates.

PATIENT SUMMARY

We looked at continence rates after nerve-sparing (NS) versus non-NS radical prostatectomy (RP). NS surgery technique but not the preservation of the neurovascular bundles led to improved long-term continence rates after RP.

Anatomy of the dorsal nerve of the penis, clinical implications

OBJECTIVE

To show the branching patterns and the anatomic variations of the dorsal nerve of the penis (DNP) along the penile shaft, particularly the relation with the tunica albuginea.

METHODS

The penises of 22 adult cadavers were dissected. The number and the diameters of the branches, the presence of anastomoses between the main trunks, the positioning of the nerves before entering the glans penis, and the presence of branches emerging from the body of the DNP and perforating the tunica albuginea were noted and photographed. The compartments where the anatomic findings were located were noted.

RESULTS

The DNP was composed of 2, 3, 4, 5, and 6 main branches in 6 (27.3%), 6 (27.3%), 6 (27.3%), 1 (4.5%), and 3 (13.6%) of 22 dissections, respectively. We could trace 2, 3, 4, and 5 terminal branches of the DNP going into the glans penis in 4 (18.2%), 8 (36.4%), 7 (31.8%), and 3 (13.6%) dissections, respectively. In 2 dissections (9.1%), fine branches were present between the main trunks crossing the midline. Anastomosing branches between ipsilateral main trunks of the DNP were identified in 5 dissections (22.7%). In 16 (72.7%) dissections, branches emerging from the inferior aspect of the body of the DNP, which perforated the tunica albuginea, could be identified.

CONCLUSION

The exact anatomic knowledge of the DNP is mandatory during penile reconstructive surgeries. The presence of branches perforating the tunica albuginea is the most important finding of this cadaveric study, together with the other documented variations, which must be taken into consideration during penile reconstructive surgeries.