Preoperative and Intraoperative Measurements of Urethral Length as Predictors of Continence After Robot-Assisted Radical Prostatectomy

Membranous urethral length measurement on preoperative MRI to predict incontinence after radical prostatectomy: a literature review towards a proposal for measurement standardization

OBJECTIVES

To investigate the membranous urethral length (MUL) measurement and its interobserver agreement, and propose literature-based recommendations to standardize MUL measurement for increasing interobserver agreement. MUL measurements based on prostate MRI scans, for urinary incontinence risk assessment before radical prostatectomy (RP), may influence treatment decision-making in men with localised prostate cancer. Before implementation in clinical practise, MRI-based MUL measurements need standardization to improve observer agreement.

METHODS

Online libraries were searched up to August 5, 2022, on MUL measurements. Two reviewers performed article selection and critical appraisal. Papers reporting on preoperative MUL measurements and urinary continence correlation were selected. Extracted information included measuring procedures, MRI sequences, population mean/median values, and observer agreement.

RESULTS

Fifty papers were included. Studies that specified the MRI sequence used T2-weighted images and used either coronal images (n = 13), sagittal images (n = 18), or both (n = 12) for MUL measurements. 'Prostatic apex' was the most common description of the proximal membranous urethra landmark and 'level/entry of the urethra into the penile bulb' was the most common description of the distal landmark. Population mean (median) MUL value range was 10.4-17.1 mm (7.3-17.3 mm), suggesting either population or measurement differences. Detailed measurement technique descriptions for reproducibility were lacking. Recommendations on MRI-based MUL measurement were formulated by using anatomical landmarks and detailed descriptions and illustrations.

CONCLUSIONS

In order to improve on measurement variability, a literature-based measuring method of the MUL was proposed, supported by several illustrative case studies, in an attempt to standardize MRI-based MUL measurements for appropriate urinary incontinence risk preoperatively.

CLINICAL RELEVANCE STATEMENT

Implementation of MUL measurements into clinical practise for personalized post-prostatectomy continence prediction is hampered by lack of standardization and suboptimal interobserver agreement. Our proposed standardized MUL measurement aims to facilitate standardization and to improve the interobserver agreement.

KEY POINTS

• Variable approaches for membranous urethral length measurement are being used, without detailed description and with substantial differences in length of the membranous urethra, hampering standardization. • Limited interobserver agreement for membranous urethral length measurement was observed in several studies, while preoperative incontinence risk assessment necessitates high interobserver agreement. • Literature-based recommendations are proposed to standardize MRI-based membranous urethral length measurement for increasing interobserver agreement and improving preoperative incontinence risk assessment, using anatomical landmarks on sagittal T2-weighted images.

Combination of deep learning and ensemble machine learning using intraoperative video images strongly predicts recovery of urinary continence after robot-assisted radical prostatectomy

BACKGROUND

We recently reported the importance of deep learning (DL) of pelvic magnetic resonance imaging in predicting the degree of urinary incontinence (UI) following robot-assisted radical prostatectomy (RARP). However, our results were limited because the prediction accuracy was approximately 70%.

AIM

To develop a more precise prediction model that can inform patients about UI recovery post-RARP surgery using a DL model based on intraoperative video images.

METHODS AND RESULTS

The study cohort comprised of 101 patients with localized prostate cancer undergoing RARP. Three snapshots from intraoperative video recordings showing the pelvic cavity (prior to bladder neck incision, immediately following prostate removal, and after vesicourethral anastomosis) were evaluated, including pre- and intraoperative parameters. We evaluated the DL model plus simple or ensemble machine learning (ML), and the area under the receiver operating characteristic curve (AUC) was analyzed through sensitivity and specificity. Of 101, 64 and 37 patients demonstrated "early continence (using 0 or 1 safety pad at 3 months post-RARP)" and "late continence (others)," respectively, at 3 months postoperatively. The combination of DL and simple ML using intraoperative video snapshots with clinicopathological parameters had a notably high performance (AUC, 0.683-0.749) to predict early recovery from UI after surgery. Furthermore, combining DL with ensemble artificial neural network using intraoperative video snapshots had the highest performance (AUC, 0.882; sensitivity, 92.2%; specificity, 78.4%; overall accuracy, 85.3%) to predict early recovery from post-RARP incontinence, with similar results by internal validation. The addition of clinicopathological parameters showed no additive effects for each analysis using DL, EL and simple ML.

CONCLUSION

Our findings suggest that the DL algorithm with intraoperative video imaging is a reliable method for informing patients about the severity of their recovery from UI after RARP, although it is not clear if our methods are reproducible for predicting long-term UI and pad-free continence.

Predictors of Urinary Continence Recovery after Laparoscopic-Assisted Radical Prostatectomy: Is Surgical Urethral Length the Only Key Factor?

Several efforts in recent years have been made to predict urinary continence (UC) recovery after radical prostatectomy. The aim of our study was to investigate the impact of surgical urethral length preservation (SULP) on urinary continence after LARP (laparoscopic-assisted radical prostatectomy). We retrospectively queried our datasets from May 2021 to May 2022. After the application of exclusion criteria, a total of 100 patients who underwent LARP for prostate cancer at our institution were enrolled. Through a sterile ruler inserted by a 12 mm trocar, the length of the membranous urethra spared during LARP was assessed intra-operatively. The baseline and peri- and postoperative data of patients were collected, and UC was defined as 0 or 1 on a safety pad. The median SULP was 20.5 mm (IQR, 14.5-25), and the median intraoperative EBL were 150 mL (IQR, 100-200). The Kaplan-Meier curve showed a significant difference at 20 mm, which was used as the cut-off value for SULP (log-rank test, p < 0.001). Multivariate Cox proportional hazards models showed that SULP and EBL < 250 mL were associated with UC recovery (all p < 0.02). Surgical urethral length preservation seemed to improve early UC recovery after LARP. Further multicentric studies are needed to confirm our findings.

Anterior Sphincter-sparing Suturing of the Vesicourethral Anastomosis During Robotic-assisted Laparoscopic Radical Prostatectomy

Background

Continence is an important functional outcome after robotic-assisted laparoscopic radical prostatectomy (RARP), and modifications of the surgical technique may improve outcomes.

Objective

To illustrate a novel RARP technique and to describe the observed continence outcomes.

Design setting and participants

A retrospective study of men treated with RARP between 2017 and 2021 was conducted.

Surgical procedure

During RARP, periprostatic structures are preserved, the intraprostatic urethra is partially spared, and the anterior anastomosis stitches involve the plexus structures but not the anterior urethra.

Measurements

A descriptive analysis of the pathological, functional, and short-term oncological outcomes was performed.

Results and limitations

Of 640 men, 448 (70%) with at least 1 yr of follow-up and a median age of 66 yr were included. The median operative time was 270 min and the prostatic volume 52 ml. The transurethral catheter was removed after a median of 3 d, and leakage of urine in the first 24 h after catheter removal was observed in 66/448 patients (15%). Positive surgical margins were reported in 104/448 (23%). Prostate-specific antigen persistence after prostatectomy was observed in 26/448 (6%). During a median follow-up of 2 yr (interquartile range 1-3 yr), the biochemical recurrence after prostatectomy was observed in 19/448 patients (4%). One year after prostatectomy, 406/448 patients (91%) were continent and required no pad at all, while 42/448 (9%) required at least one pad per day.

Conclusions

Not stitching the anterior urethra is a novel technical modification and may improve continence outcomes.

Patient summary

We describe a novel way to stitch the bladder neck to the urethra after removal of the prostate using a surgical robotic system. Our technique appeared safe, with promising urinary continence results.

"Urethral-Sparing" Robotic Radical Prostatectomy: Critical Appraisal of the Safety of the Technique Based on the Histologic Characteristics of the Prostatic Urethra

BACKGROUND

The prostatic urethra (PU) is conventionally resected during robot-assisted radical prostatectomy (RALP). Recent studies demonstrated the feasibility of the extended PU preservation (EPUP).

AIMS

To describe the histologic features of the PU.

METHODS

The PU was evaluated using cystoprostatectomy and RALP specimens. Cases of PU infiltration by prostate cancer or distortion by benign hyperplastic nodules were excluded. The thickness of the chorion and distance between the urothelium and prostate glands were measured. Prostate-specific antigen expression in the PU epithelium was evaluated with immunohistochemistry. Descriptive statistics were used.

RESULTS

Six specimens of PU were examined. Histologically, the following layers of the PU were observed: (1) urothelium with basal membrane, (2) chorion, and (3) prostatic peri-urethral fibromuscular tissue. The chorion measures between 0.2 and 0.4 mm. There is not a distinct urethral muscle layer, but rather muscular fibers that originate near the prostatic stroma and are distributed around the PU. This muscular tissue appears to be mainly represented in the basal and apical urethra, but not in the middle urethra. The mean distance between the chorion and prostatic glands is 1.74 mm, with significant differences between base of the prostate, middle urethral portion, and apex (2.5 vs. 1.49 vs. 1.23 mm, respectively). PSA-expressing cells are abundant in the PU epithelium, coexisting with urothelial cells.

CONCLUSIONS

The exiguity of thickness of the PU chorion, short distance from glandular tissue, and coexistence of PSA-expressing cells in the epithelium raise important concerns about the oncologic safety of EPUP.

Significance of postoperative membranous urethral length and position of vesicourethral anastomosis for short-term continence recovery following robot-assisted laparoscopic radical prostatectomy

BACKGROUND

We assess whether short-term recovery of urinary incontinence following robot-assisted laparoscopic radical prostatectomy (RARP) is associated with postoperative membranous urethral length (MUL) and position of vesico-urethral anastomosis (PVUA).

METHODS

Clinical variables including PVUA and pre-and postoperative MUL were evaluated in 251 patients who underwent RARP from August 2019 to February 2021. Continence recovery was defined as no pad or one security liner per day assessed by patient interview at least 6 months follow-up. Univariate and multivariate logistic regression analyses were used to assess variables associated with continence recovery at 3 months after the operation.

RESULTS

Continence recovery rates at 3 and 6 months were 75% and 84%, respectively. Lower BMI (< 25 kg/m²) (p = 0.040), longer preoperative MUL (≥ 9.5 mm) (p = 0.013), longer postoperative MUL (≥ 9 mm) (p < 0.001), higher PVUA (< 14.5 mm) (p = 0.019) and shorter operating time (< 170 min) (p = 0.013) were significantly associated with continence recovery at 3 months in univariate analysis. Multivariate analysis revealed that postoperative MUL (OR 3.75, 95% CI 1.90-7.40, p < 0.001) and higher PVUA (OR 2.02, 95% CI 1.07-3.82, p = 0.032) were independent factors for continence recovery. Patients were divided into 3 groups based on the multivariate analysis, with urinary continence recovery rates found to have increased in turn with rates of 43.7% versus 68.2% versus 85.0% (p < 0.001) at 3 months.

CONCLUSIONS

PVUA and postoperative MUL were significant factors for short-term continence recovery. Preservation of urethral length might contribute to continence recovery after RARP.

Value of Different Magnetic Resonance Imaging-based Measurements of Anatomical Structures on Preoperative Prostate Imaging in Predicting Urinary Continence After Radical Prostatectomy in Men with Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

Measurements of anatomical structures on preoperative prostate magnetic resonance imaging (MRI) are used in risk models for treatment decisions to predict urinary continence (UC) following radical prostatectomy (RP). However, the association between these parameters and UC is unclear.

OBJECTIVE

To systematically summarize the literature on prognostic preoperative prostate MRI measurements of (peri)prostatic structures in relation to time to recovery of postoperative UC in men with prostate cancer.

EVIDENCE ACQUISITION

Online libraries were searched up to August 27, 2021. Article selection and critical appraisal were performed by two reviewers. All papers reporting on preoperative MRI measurements with UC correlation in univariable or multivariable analyses were included.

EVIDENCE SYNTHESIS

In the 50 studies included (mostly retrospective), 57 MRI parameters were evaluated. The pooled analyses showed that greater membranous urethra length (MUL) was prognostic for regaining UC at 1 mo (odds ratio [OR] 1.15, 95% confidence interval [CI] 1.10-1.21), 3 mo (OR 1.23, 95% CI 1.16-1.31), 6 mo (OR 1.16, 95% CI 1.08-1.25), and 12 mo (OR 1.19, 95% CI 1.10-1.29). Several other anatomical structures showed at least in one study a significant correlation with later return to UC: four prostate-related parameters (greater depth, apical protrusion, larger intravesical protrusion, small dorsal vascular complex), five urethra-related parameters (thicker wall, severe fibrosis, smaller volume, larger preoperative angle between the prostate axis and membranous urethra, shorter minimal residual MUL), and six musculoskeletal-related parameters (lower perfusion ratio, thinner levator ani muscle, larger inner or outer levator distance, shorter pelvic diaphragm length, and larger midpelvic area).

CONCLUSIONS

Greater MUL as measured on preoperative MRI was an independent prognostic factor for return to UC within 1 mo after RP and remained prognostic at 12 mo. Other anatomical structures may potentially be predictive, but these would need to be substantiated in prospective trials before being adopted in postoperative UC risk models for treatment decisions in men with prostate cancer.

PATIENT SUMMARY

We summarized study data on the relation between measurements of anatomical structures on preoperative magnetic resonance imaging scans and urinary continence after removal of the prostate. Greater length of one part of the urethra (membranous urethra) is associated with faster return to continence. Other anatomical structures have potential for predicting postoperative continence, but need further investigation.

Impact of Pelvic Anatomical Changes Caused by Radical Prostatectomy

Simple Summary

After radical prostatectomy, the pelvic anatomy is altered such that the postoperative structure differs from the preoperative one, resulting in a variety of complications. In this review, the complications and mechanisms of pelvic anatomical changes associated with radical prostatectomy, as well as countermeasures, are outlined. An analysis of the anatomical mechanisms that cause complications after radical prostatectomy using imaging and other modalities is in progress. In addition, many surgical techniques that ensure the prevention of postoperative complications have been reported, and their usefulness has been evaluated. The preservation of as much periprostatic tissue and periprostatic structures as possible may lead to favorable postoperative functions, as long as the cancer condition permits.

Abstract

During radical prostatectomy, the prostate is removed along with the seminal vesicles, and the urinary tract is reconstructed by dropping the bladder onto the pelvic floor and suturing the bladder and urethra together. This process causes damage to the pelvic floor and postoperative complications due to the anatomical changes in the pelvic floor caused by the vesicourethral anastomosis. Urinary incontinence and erectile dysfunction are major complications that impair patients’ quality of life after radical prostatectomy. In addition, the shortening of the penis and the increased prevalence of inguinal hernia have been reported. Since these postoperative complications subsequently affect patients’ quality of life, their reduction is a matter of great interest, and procedural innovations such as nerve-sparing techniques, Retzius space preservation, and inguinal hernia prophylaxis have been developed. It is clear that nerve sparing is useful for preserving the erectile function, and nerve sparing, urethral length preservation, and Retzius sparing are useful for urinary continence. The evaluation of pre- and postoperative imaging to observe changes in pelvic anatomy is also beginning to clarify why these techniques are useful. Changes in pelvic anatomy after radical prostatectomy are inevitable and, therefore, postoperative complications cannot be completely eliminated; however, preserving as much of the tissue and structure around the prostate as possible, to the extent that prostate cancer control is not compromised, may help reduce the prevalence of postoperative complications.

Preoperative Prostate MRI Predictors of Urinary Continence Following Radical Prostatectomy

Background Urinary continence after radical prostatectomy (RP) is an important determinant of patient quality of life. Anatomic measures at prostate MRI have been previously associated with continence outcomes, but their predictive ability and interrater agreement are unclear in comprehensive clinical models. Purpose To evaluate the predictive ability and interrater agreement of MRI-based anatomic measurements of post-RP continence when combined with clinical multivariable models. Materials and Methods In this retrospective cohort study, continence outcomes were evaluated in men who underwent RP from August 2015 to October 2019. Preoperative MRI-based anatomic measures were obtained retrospectively by four abdominal radiologists. Before participation, these radiologists completed measure-specific training. Logistic regression models were developed with clinical variables alone, MRI variables alone, and combined variables for predicting continence at 3, 6, and 12 months after RP; some patient data were missing at each time point. Interrater agreement of MRI variables was assessed by using intraclass correlation coefficients (ICCs). Results A total of 586 men were included (mean age ± standard deviation: 63 years ± 7). The proportion of patients with incontinence was 0.2% (one of 589) at baseline, 27% (145 of 529) at 3 months, 14% (63 of 465) at 6 months, and 9% (37 of 425) at 12 months. Longer coronal membranous urethra length (MUL) improved the odds of post-RP continence at all time points (odds ratio per 1 mm: 0.86 [95% CI: 0.80, 0.93], P < .001; 0.86 [95% CI: 0.78, 0.95], P = .003; and 0.79 [95% CI: 0.67, 0.91], P = .002, respectively) in models that incorporated both clinical and MRI predictors. No other MRI variables were predictive. Age and baseline urinary function score were the only other predictive clinical variables at every time point. Interrater agreement was moderate (ICC, 0.62) for MUL among readers with measure-specific prostate MRI training and poor among those without the training (ICC, 0.38). Conclusion Preoperative MRI-measured coronal membranous urethra length was an independent predictor of urinary continence after prostatectomy. © RSNA, 2022 Online supplemental material is available for this article.

Longer preserved urethral length in robot‐assisted radical prostatectomy significantly contributes to post‐operative urinary continence recovery

Objectives

To assess the relationship between the surgical procedure of robot‐assisted radical prostatectomy (RARP) and urinary continence recovery by reviewing the video database.

Methods

Video and data about men diagnosed with prostate cancer and underwent RARP were extracted and reviewed. Preserved urethral length (PUL) was semi‐quantitatively measured using the lateral width of a 16‐Fr urethral balloon catheter while cutting the urethra on a video screen. In addition, by reviewing intraoperative RARP video database, other surgical skill outcomes were also collected. Kaplan–Meier analysis with log‐rank test was used to compare the urinary continence recovery rate, stratified by the PUL. Univariate and multivariate analyses were performed using the Cox proportional hazards model, and p‐values of <0.05 were considered significant.

Results

The number of patients included in this study was 213. In univariate analysis, a PUL of ≥16 mm, a body mass index of <23.1 kg/m² and a resected prostate volume of <44.3 g were statistically significant factors that influenced urinary continence recovery [hazard ratio (HR) 1.58, p = 0.036; HR 0.67, p = 0.021; and HR 0.58, p = 0.005, respectively]. Those factors also remained statistically significant in the multivariate analysis (HR 1.87, p = 0.022; HR 0.54, p = 0.001; and HR 0.57, p = 0.005, respectively). One year post‐operatively, the recovery rate from urinary continence was 79.0% for patients with a PUL of ≥16 mm and 66.5% for patients with a PUL of <16 mm.

Conclusion

These results suggest that patients with longer PUL in RARP have a significantly higher rate of post‐operative urinary continence recovery.

Evaluation of image-based prognostic parameters of post-prostatectomy urinary incontinence: A literature review

Prostate cancer is the second most common male cancer, and radical prostatectomy is a highly effective treatment for intermediate and high-risk disease. However, post-prostatectomy urinary incontinence remains a major functional side-effect in patients undergoing radical prostatectomy. Despite recent improvements in preoperative imaging quality and surgical techniques, it remains challenging to predict or prevent occurrence of this complication. The aim of this research was to review the current published literature on pre- and postoperative imaging evaluation of the prostate and pelvic structures, to identify added value in the prediction of post-prostatectomy urinary incontinence. A computerized bibliographic search of the PubMed library was carried out to identify imaging-based articles evaluating the pelvic floor and surrounding structures pre- and/or postradical prostatectomy to predict post-prostatectomy urinary incontinence. A total of 32 articles were included. Of these, 29 papers assessed the importance of magnetic resonance imaging evaluation, with a total of 16 parameters evaluated. The most common parameters were intravesical protrusion, the membranous urethral length, prostatic volume and periurethral fibrosis. Preoperative membranous urethral length and its preservation after surgery showed the strongest correlation with urinary incontinence. Three studies evaluated ultrasound, with all carried out postoperatively. This technique benefits from a dynamic evaluation, and the results are promising for proximal urethral hypermobility and the degree of bladder neck funneling on the Valsalva maneuver. Several imaging studies evaluated the predictors of post-prostatectomy urinary incontinence, with preoperative membranous urethral length offering the most promise. However, the current literature is limited by the single-center nature of studies, and the heterogeneity in patient populations and methodologies used.

Bladder neck sparing during robot-assisted laparoscopic radical prostatectomy: Six-year experience

OBJECTIVE:

Prostate cancer is the most frequently diagnosed cancer among men in developed countries. Radical prostatectomy (RP) is the standard surgical treatment for patients with organ-confined disease and robot-assisted laparoscopic radical prostatectomy (RALP) procedures get more popular in the past 20 years. The most important factor of continence after RP is the preservation of the functional sphincter mechanisms. Tunc et al. described the novel bladder neck preserving technique in RALRP in 2015. The purpose of this study is to present our long-term results of our novel technique during RALP performed by single surgeon (LT).

METHODS:

In this study, 331 patients who went under procedure RALP between January 2012 and December 2017 analyzed retrospectively. Bladder neck sparing technique was performed for all patients used by a four-armed da Vinci robotic surgical system (Intuitive Surgical, Inc., Sunnyvale, CA). Quality of life (QoL) scores were assessed before RALP, after urethral catheter removal, and at the 1^st month after RALP used by SF-12 QoL questionnaire. Patients without urine leakage during coughing or sneezing, as well as those who stayed totally dry, were considered as continent. Those who used more than 1 protective pad per day and/or had urine leakage during coughing, sneezing, or during the night were considered incontinent.

RESULTS:

The mean operation time, docking time, and anastomosis time were 76.9±28.9, 7.2±2.2, and 18±3.1 min, respectively. Estimated blood loss was 51.6±22.9 ml. The mean hospital stay was 2.2±0.8 days. The mean duration of the catheter was 7.1±1.3 days. After catheter removal, 310 (93.6%) of patients were continent immediately. During follow-up, 318 (96%) were continent after 1 month and 329 (99.3%) were totally continent after 1 year. No patient received surgical treatment for stress incontinence.

CONCLUSION:

Since we have defined bladder neck sparing technique, we have realized that our technique is very effective with our long-term results. Our novel technique provided very early continence at the time of catheter removal after RALP within short-term follow-up in addition to favorable oncologic results.

Effect of prostatic apex shape (Lee types) and urethral sphincter length in preoperative MRI on very early continence rates after radical prostatectomy

Purpose

To test the effect of anatomic variants of the prostatic apex overlapping the membranous urethra (Lee type classification), as well as median urethral sphincter length (USL) in preoperative multiparametric magnetic resonance imaging (mpMRI) on the very early continence in open (ORP) and robotic-assisted radical prostatectomy (RARP) patients.

Methods

In 128 consecutive patients (01/2018–12/2019), USL and the prostatic apex classified according to Lee types A–D in mpMRI prior to ORP or RARP were retrospectively analyzed. Uni- and multivariable logistic regression models were used to identify anatomic characteristics for very early continence rates, defined as urine loss of ≤ 1 g in the PAD-test.

Results

Of 128 patients with mpMRI prior to surgery, 76 (59.4%) underwent RARP vs. 52 (40.6%) ORP. In total, median USL was 15, 15 and 10 mm in the sagittal, coronal and axial dimensions. After stratification according to very early continence in the PAD-test (≤ 1 g vs. > 1 g), continent patients had significantly more frequently Lee type D (71.4 vs. 54.4%) and C (14.3 vs. 7.6%, p = 0.03). In multivariable logistic regression models, the sagittal median USL (odds ratio [OR] 1.03) and Lee type C (OR: 7.0) and D (OR: 4.9) were independent predictors for achieving very early continence in the PAD-test.

Conclusion

Patients’ individual anatomical characteristics in mpMRI prior to radical prostatectomy can be used to predict very early continence. Lee type C and D suggest being the most favorable anatomical characteristics. Moreover, longer sagittal median USL in mpMRI seems to improve very early continence rates.

Transperineal ultrasound as a reliable tool in the assessment of membranous urethra length in radical prostatectomy patients

To evaluate the usefulness of transperineal ultrasound (TPUS) as a method of membranous urethra length (MUL) measurement and investigate whether preoperative (MULpre) and postoperative (MULpost) would be associated with the degree and time of urinary continence recovery after laparoscopic radical prostatectomy (LRP). 84 patients who underwent LRP between January 2017 and December 2018 were selected for final analysis. All patients had preoperative and postoperative measurement of MUL in TPUS. Urinary continence was defined as no pad or a safety pad. Recovery of continence was assessed at 1, 3, 6 and 12 months after catheter removal. We prospectively analyzed correlation of MULpre, MULpost and a percent change in membranous urethral length (MULratio) with the urinary continence status. 69 (82%) patients regained continence in the follow-up of 12 months. MULpre, MULpost and MULratio assessed in TPUS were larger in subgroups of patients who regained continence earlier and in the entire continent group. Spearman rank test showed strong correlations between MULpost and MULratio (R-0.6 and R-0.56, respectively, p < 0.0001) with the time to continence recovery in the cumulative 12 months follow-up. TPUS allowed a reliable measurement of MUL before and after LRP. MULpre, MULpost as well as MULratio are related with time to regain continence and recovery rate after LRP. Sparing longest possible sphincteric urethra, with respect to oncological outcomes is a key factor in recovering continence after prostate cancer surgery.

Postoperative membranous urethral length is the single most important surgical factor predicting recovery of postoperative urinary continence

PURPOSE

To analyze the potential surgical factors affecting postoperative urinary continence, including postoperative membranous urethral length (MUL), in an era where open radical prostatectomy (ORP) and robot-assisted radical prostatectomy (RARP) coexist.

METHODS

Consecutive patients undergoing either ORP or RARP between April 2009 and June 2017 were included in this study. Pericatheter urethrography (PCU) was performed the day of catheter removal to confirm healing of the vesicourethral anastomosis and to measure PCU-MUL. Daily usage of incontinence pad was self-reported by the patient at each post-operative visit through a questionnaire. Univariate and multivariate analyses were performed to identify factors that influenced recovery of continence.

RESULTS

Of the 196 patients included, 121 and 75 patients received ORP and RARP, respectively. The cumulative full continence rates (0 pad/day) at 1 year in the ORP and RARP groups were 87% and 95%, respectively. In the univariate analysis, older age, high preoperative International Prostate Symptom Score (IPSS) irritative symptom domain, ORP, poorer NVB preservation, and shorter PCU-MUL were associated with delayed recovery of full continence. In the multivariate analysis, only older age, high preoperative IPSS irritative symptom domain, and shorter PCU-MUL remained as independent factors significantly associated with delayed recovery of full continence.

CONCLUSIONS

Our study highlights the importance of saving the MUL as long as possible in terms of continence recovery. This holds true for ORP even in the era of RARP and surgeons should not simply give up the prospect of early urinary continence in exchange for the patient's choice of ORP instead of RARP.

How to Prevent and Manage Post-Prostatectomy Incontinence: A Review

PURPOSE

To provide an overview of the currently available evidence relating to the prevention and management strategies of urinary incontinence (UI) after radical prostatectomy (RP).

MATERIALS AND METHODS

A comprehensive research was carried out on MEDLINE/PubMed database to identify pertinent studies concerning post-RP UI. The search strategy included these words: urinary continence; urinary continence recovery; urinary incontinence; radical prostatectomy; and prostate cancer.

RESULTS

Post-RP UI still represents a challenging issue for both urologic patients and clinicians. A complete preoperative assessment of the risk factors associated with post-RP UI aids both in counseling those patients with a higher estimated likelihood of postoperative UI and in identifying those who would probably benefit from preventive strategies in the preoperative and in the intraoperative settings. Over the last decades different surgical strategies based on either the "preservation" or the "reconstruction" of the anatomical elements responsible for urinary continence (UC) led to an overall improvement of postoperative functional outcomes. Finally, several therapeutic strategies should be evaluated for the postoperative UI management. Artificial urinary sphincter implantation represents the gold standard for treatment, notwithstanding its wide adoption is limited due to high costs and significant risk of surgical revision. In this context, male sling positioning seems the most promising strategy, in particular in mild and moderate post-RP UI.

CONCLUSIONS

To enhance the likelihood of obtaining an optimal UC recovery after RP, it is here strongly suggested to intervene throughout the overall clinical management process thus including the pre-, intra- and postoperative settings.

Deep learning using preoperative magnetic resonance imaging information to predict early recovery of urinary continence after robot-assisted radical prostatectomy

OBJECTIVES

To investigate whether a deep learning model from magnetic resonance imaging information is an accurate method to predict the risk of urinary incontinence after robot-assisted radical prostatectomy.

METHODS

This study included 400 patients with prostate cancer who underwent robot-assisted radical prostatectomy. Patients using 0 or 1 pad/day within 3 months after robot-assisted radical prostatectomy were categorized into the "good" group, whereas the other patients were categorized into the "bad" group. Magnetic resonance imaging DICOM data, and preoperative and intraoperative covariates were assessed. To evaluate the deep learning models from the testing dataset, their sensitivity, specificity and area under the receiver operating characteristic curve were analyzed. Gradient-weighted class activation mapping was used to visualize the regions of deep learning interest.

RESULTS

The combination of deep learning and naive Bayes algorithm using axial magnetic resonance imaging in addition to clinicopathological parameters had the highest performance, with an area under the receiver operating characteristic curve of 77.5% for predicting early recovery from post-prostatectomy urinary incontinence, whereas machine learning using clinicopathological parameters only achieved low performance, with an area under the receiver operating characteristic curve of 62.2%. The gradient-weighted class activation mapping methods showed that deep learning focused on pelvic skeletal muscles in patients in the good group, and on the perirectal and hip joint regions in patients in the bad group.

CONCLUSIONS

Our results suggest that deep learning using magnetic resonance imaging is useful for predicting the severity of urinary incontinence after robot-assisted radical prostatectomy. Deep learning algorithms might help in the choice of treatment strategy, especially for prostate cancer patients who wish to avoid prolonged urinary incontinence after robot-assisted radical prostatectomy.

Impact of surgically maximized versus native membranous urethral length on 30-day and long-term pad-free continence after robot-assisted radical prostatectomy

BACKGROUND

Pelvic multiparametric magnetic resonance imaging (mpMRI)-determined membranous urethral length (MUL) and its surgical maximization have been reported to impact early- and long-term pad-free urinary continence after robot-assisted radical prostatectomy (RARP).

OBJECTIVE

The objective of this study was to present evidence (data and video) of important effects on post-RARP continence recovery from both innate mpMRI-assessed and surgical preservation of MUL.

DESIGN SETTING AND PARTICIPANTS

Of 605 men undergoing RARP, 580 with complete follow-up were included: Group 1, prior (N = 355), and Group 2, subsequent (N = 225) to technique change of MUL maximization. Effect of innate, mpMRI-assessed MUL on postoperative continence was assessed.

SURGICAL PROCEDURE

Before technique change, the dorsal venous complex was stapled before transection of the membranous urethra. After the change, the final step of extirpation was transection of the dorsal venous complex and periurethral attachments, thus facilitating surgical maximization of MUL.

MEASUREMENTS

Primary and secondary outcomes for technique change and mpMRI-assessed MUL were both patient-reported 30-day and 1-year pad-free continence after RARP, respectively.

RESULTS

Preoperative prostate-specific antigen, age, and disease aggressiveness were significantly higher in Group 2. After technique change and surgical maximization of MUL, 30-day and 1-year pad-free continence were both significantly improved (p < 0.05). In multivariate analysis, maximization of MUL significantly increased the likelihood of both early- and long-term continence recovery. For men undergoing MUL preservation, mpMRI-assessed MUL>1.4 cm also independently predicted higher 30-day (odds ratio: 4.85, 95% confidence interval: 1.24-18.9) and 1-year continence recovery (odds ratio: 11.26, 95% confidence interval: 1.07-118).

CONCLUSIONS

Prostatic rotation and circumferential release of apical attachments and maximization of MUL improves continence after RARP. Separately, innate MUL>1.4 cm independently increased 30-day and 1-year continence recovery.

PATIENT SUMMARY

Surgeon efforts to maximize MUL during radical prostatectomy are highly encouraged, as maximally preserved MUL likely improves post-RARP continence recovery. In addition, individual patients' mpMRI-assessed MUL (approximately >1.4 cm) independently limits continence recovery.

Association of preoperative urethral parameters on magnetic resonance imaging and immediate recovery of continence following Retzius-sparing robot-assisted radical prostatectomy

Background

Studies regarding predictive factors of urinary continence following Retzius-sparing radical prostatectomy (RP) is limited. This study was designed to evaluate association of urethral parameters on preoperative magnetic resonance imaging (MRI) and immediate recovery of urinary continence following Retzius-sparing robot assisted radical prostatectomy (RS-RARP).

Methods

This retrospective cohort study enrolled 156 patients with clinically localized prostate cancer who underwent MRI before RS-RARP. We measured the following structures on preoperative MRI: minimal residual membranous urethral length (mRUL), peri-urethral sphincter complex (PSC) thickness, urethral wall thickness (UWT), the thicknesses of the levator ani muscle (LAM) and obturator internus muscle (OIM). Immediate urinary continence was defined as patients reported freedom from using safety pad within 7 days after removal of urinary catheter. Patients were divided into two groups according the median of each parameter on MRI. We retrospectively analyzed the patients in term of preoperative clinical factors and postoperative urinary continence.

Results

A total of 100 patients (64.1%) reported immediate urinary continence after RS-RARP. Immediate urinary continence was significantly more in patients with longer mRUL (≥8.70 mm) than in patients with shorter mRUL (<8.70 mm; P=0.000). On multivariable analysis, longer mRUL was significantly related to immediate urinary continence after RS-RAPA (odds ratio 8.265; P=0.000). PSC, UWT, LAM and OIM were not associated with immediate urinary continence.

Conclusions

Our results firstly demonstrated that preoperative mRUL measured on MRI was an independent predictor of immediate urinary continence following RS-RARP. Therefore, preservation of membranous urethra is still the anatomical basis of better urinary outcome after RS-RARP.

Feasibility and continence outcomes of extended prostatic urethral preservation during robot-assisted radical prostatectomy

BACKGROUND

The prostatic urethra is conventionally resected during robot-assisted radical prostatectomy (RARP). We describe the technical feasibility and urinary continence outcomes of extended prostatic urethral preservation (EPUP) during RARP.

METHODS

A single surgeon at a National Comprehensive Cancer Network institute performed 48 consecutive RARP operations using EPUP from March 2014 to March 2016, during which time 177 conventional non-EPUP RARP operations were performed by other surgeons. Prior to this period, the EPUP surgeon had performed 17 non-EPUP RARP operations over 15 months. Total intracorporeal urethral length (IUL) preserved during EPUP was measured intraoperatively. Associations of EPUP and IUL with continence recovery rates and/or times were tested in Fisher's exact and log rank univariate analyses and Cox logistic regression multivariable analyses.

RESULTS

Median IUL preserved during EPUP was 4.0 cm (range 2.5-6.0 cm), and urethral dissections typically spanned the prostatic apex to mid-gland or base. Seven-week continence rates were significantly higher with versus without EPUP. EPUP patient rates of using 0 or 0-1 pads per day immediately after catheter removal were 19% and 35%, respectively. These rates increased significantly (53% and 76%, respectively), as did the IUL preserved (median 5.0 cm), among more recent EPUP patients (n = 17), which suggested a learning curve. In multivariable analyses including all patients, an EPUP approach was an independent predictor of faster continence recovery. In multivariable analyses of the EPUP subset, a longer IUL preserved was independently associated with faster continence recovery. No EPUP patient had a urethral fossa positive margin, and apical positive margins were similarly infrequent among EPUP and non-EPUP patients.

CONCLUSIONS

EPUP is technically feasible during RARP and associated with faster continence recovery. Future investigation into the generalizability of these findings and the oncologic safety of EPUP is warranted.

Improvement in early urinary continence recovery after robotic-assisted radical prostatectomy based on postoperative pelvic anatomic features: a retrospective review

Background

We investigated the impact of postoperative membranous urethral length and other anatomic characteristics of the pelvic floor shape as measured by magnetic resonance imaging on the improvement in continence following robotic-assisted radical prostatectomy.

Methods

We retrospectively reviewed data from 73 patients who underwent postoperative prostate magnetic resonance imaging following robotic-assisted radical prostatectomy between 2013 and 2018. Patient demographics; pre-, peri-, and post-operative parameters; and pelvic anatomic features on magnetic resonance imaging were reviewed. Patients who used no urinary incontinence pads or pads for protection were considered to have achieved complete continence.

Results

Urinary continence was restored in 27.4, 53.4, 68.5, and 84.9% of patients at 1, 3, 6, and 12 months after robotic-assisted radical prostatectomy, respectively. When patients were divided into early and late continence groups based on urinary continence at 3 months after robotic-assisted radical prostatectomy, no significantly different clinical characteristics or surgical outcomes were found. However, the mean membranous urethral length (18.5 mm for the early continence group vs. 16.9 mm for the late continence group), levator muscle width (7.1 vs. 6.5 mm, respectively), and bladder neck width on the trigone side (7.2 mm vs. 5.4 mm, respectively) were significantly different between groups (all p < 0.05). Multivariate logistic regression analysis showed that membranous urethral length (odds ratio, 1.227; 95% confidence interval, 1.011–1.489; p = 0.038) and bladder neck width (odds ratio, 1.585; 95% confidence interval, 1.050–2.393; p = 0.028) were associated with the period of early urinary continence.

Conclusions

Postoperative membranous urethral length and bladder neck width were significantly associated with early urinary continence recovery after robotic-assisted radical prostatectomy. It is highly recommended that surgeons focus on preserving the membranous urethral length and increasing the bladder neck width on the trigone side during surgery to achieve optimal continence outcomes after robotic-assisted radical prostatectomy.

Preoperative MRI Parameters Predict Urinary Continence after Robot-Assisted Laparoscopic Prostatectomy in Prostatic Cancer Patients

We aimed to investigate whether preoperative MRI findings could predict the bladder neck location on postoperative cystography and recovery of urinary incontinence after robot-assisted laparoscopic radical prostatectomy (RALP). We retrospectively reviewed 270 consecutive patients who had complete preoperative data, including MRI, and underwent postoperative observation for more than three months. Preoperative MRI parameters consisted of the membranous urethral length (MUL) and pubic symphysis-prostate apex length (PAL) on sagittal images. The bladder neck location on a postoperative cystography was defined as the lowest extension of the tapering contrast medium in the bladder, and its relation to the pubic symphysis (above (higher group) and below (lower group) the middle of the pubic symphysis height) was evaluated. Those who required no pad or a safety pad were defined as being continent. PAL was significantly shorter in the higher group than that in the lower group (25.5 vs. 29.1 mm; p < 0.0001). The continent group at three months had a significantly longer MUL and shorter PAL than those in the incontinent group (8.1 vs. 6.7 mm; p < 0.05, and 26.0 vs. 28.1 mm; p < 0.05, respectively). Preoperative MRI parameters could predict the bladder neck location on postoperative cystograms and the recovery of urinary incontinence after RALP.

Preoperative magnetic resonance imaging in predicting early continence recovery after robotic radical prostatectomy

INTRODUCTION AND AIMS

Urinary incontinence is a common complication after radical prostatectomy. The aim of our study was to describe the preoperative anatomical features using magnetic resonance imaging in order to predict early continence recovery after robotic radical prostatectomy.

MATERIAL AND METHODS

72 patients who underwent robotic radical prostatectomy were prospectively analysed. EPIC questionnaire (1, 6 and 12 mo) and first self-reported continence were used to assess functional outcomes. Membranous urethral length (MUL) and MUL-prostate axis angle (aMULP) were assessed preoperatively on T2 weighted sagittal images.

RESULTS

Continence rate was 67.2%, 92.6% and 95.2% at 1, 6 and 12 months, respectively. Early continence was achieved in patients with the lower aMULP. At 1 month, average aMULP in continent patients was 107.21° (IC 95% 90.3-124.6) vs. 118.5° (IC 95% 117.7-134) in incontinent ones (P=.014). At 6 month differences in aMULP among groups were found: 114.24° (IC 95% 104.6-123.9) in continents vs. 142° (IC 95% 126.5-157.6) in incontinents (P=0.015). At 12 month, continent group showed a significantly higher preoperative aMULP. aMULP was revealed as the only independent predictor of urinary continence at 6 mo in multivariate analysis, OR 0.007 (IC 95% 0.002-0.012), P=0.012.

CONCLUSIONS

Preoperative anatomical parameters assessment prior surgery can help to identified those patients will achieve early continence recovery and it supports therapeutic decisions making.

Investigating the mechanism underlying urinary continence recovery after radical prostatectomy: effectiveness of a longer urethral stump to prevent urinary incontinence

OBJECTIVE

To assess the chronological changes in urinary incontinence and urethral function before and after radical prostatectomy (RP), and to compare the findings of pelvic magnetic resonance imaging (MRI) before and after RP to evaluate the anatomical changes.

PATIENTS AND METHODS

In total, 185 patients were evaluated with regard to the position of the distal end of the membranous urethra (DMU) on a mid-sagittal MRI slice and urethral sphincter function using the urethral pressure profilometry. The patients also underwent an abdominal leak point pressure test before RP and at 10 days and 12 months after RP. The results were then compared with the chronological changes in urinary incontinence.

RESULTS

The MRI results showed that the DMU shifted proximally to an average distance of 4 mm at 10 days after RP and returned to the preoperative position at 12 months after RP. Urethral sphincter function also worsened 10 days after RP, with recovery after 12 months. The residual length of the urethral stump and urinary incontinence were significantly associated with the migration length of the DMU at 10 days after RP. The residual length of the urethral stump was a significant predictor of urinary incontinence after RP.

CONCLUSION

This is the first study to elucidate that the slight vertical repositioning of the membranous urethra after RP causes chronological changes in urinary incontinence. A long urethral residual stump reduces urinary incontinence after RP.

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.

Prevalence analysis of urinary incontinence after radical prostatectomy and influential preoperative factors in a single institution

AIMS

To assess prevalence of urinary incontinence (UI) after radical prostatectomy (RP) and to analyze which preoperative characteristics of the patients have influence on UI.

METHODS

Between 2002 and 2012, 746 consecutive patients underwent RP for clinically localized prostate cancer. We defined UI according to International Continence Society (ICS) definition: "the complaint of any involuntary leakage of urine" after 12 months of recovery, international consultation on incontinence questionnaire (ICIQ-SF) and pads/day was collected too. Clinical features and magnetic resonance imaging measurements were assessed. A multivariable logistic regression model predicting incontinence were built-in after adjust by cofounding factors and bootstrapping.

RESULTS

About 172 (23%) of the patients were classified as incontinent according to the ICS definition. The mean value of the ICIQ-SF was 10.87 (±4). 17.8% of patients use at least one pad/day, 11.9% use more than one pad/day. The preoperative factors independently influential in UI are: age [OR: 1.055; CI 95% (1.006-1.107), p = .028], urethral wall thickness [OR: 5.03; CI 95% (1.11-22.8), p = .036], history of transurethral resection of the prostate [OR: 6.13; CI 95% (1.86-20.18), p = .003] and membranous urethral length [OR: 0.173; CI 95% (0.046-0.64), p = .009]. The predictive accuracy of the model is 78.7% and the area under the curve (AUC) value 71.7%.

CONCLUSIONS

Urinary incontinence after radical prostatectomy has different prevalence depending on the definition. Age, prior transurethral resection of the prostate (TURP), membranous urethral length (MUL) and urethral wall thickness (UWT) were risk factors.

Review of optimal techniques for robotic-assisted radical prostatectomy

PURPOSE OF REVIEW

Robotic-assisted radical prostatectomy has been rapidly adopted and is now the standard of care in the surgical management of prostate cancer. Since the initial description in 2001, the technique has evolved to optimize oncological functional outcomes. Herein, we review key techniques for the robotic-assisted radical prostatectomy.

RECENT FINDINGS

With the current influx of new technology such as focal therapy, stereotactic body radiation therapy and prostate-sparing treatments, there is greater emphasis on maximizing outcomes of robotic-assisted radical prostatectomy. The evidence-based techniques of optimizing oncological outcomes including the lymph node dissection and improving cancer control through minimizing positive surgical margins are reviewed. Improvements in functional recovery has also been seen with technical modifications such as nerve sparing, preservation of the urethral support structures and the bladder neck and the urethra-vesical reconstruction.

SUMMARY

Robotic prostatectomy has demonstrated adequate long-term oncologic success and satisfactory functional recovery. As technology and techniques in robotic-assisted surgery evolve, surgeons will continue to optimize techniques to maximize functional outcome recovery and cancer control. Further studies are actively being conducted to provide level one evidence in multiple aspects of the robotic-assisted radical prostatectomy.

Literature review of factors affecting continence after radical prostatectomy

Radical prostatectomy (RP) is the most common cause of stress urinary incontinence (UI) in men. Several anatomic structures affect or may affect urinary continence - urethral sphincter, levator ani muscle, puboprostatic ligaments, bladder neck, endopelvic fascia, neurovascular bundle - and understanding of the anatomy of pelvic floor and urethra is crucial for satisfactory functional outcome of the procedure. Surgical techniques implemented to improve continence rates include nerve-sparing procedure, bladder neck preservation/plication, urethral length preservation, musculofascial reconstruction, puboprostatic ligaments preservation or seminal vesicle preservation. Perioperative (preoperative and postoperative) pelvic floor muscle training (PFMT) aims to shorten the duration of postoperative UI and thus, improve early continence rates postoperatively. In the review, complex information regarding anatomical, intra- and perioperative factors affecting urinary continence after RP is provided, including description of important anatomical structures, possible implications for surgical technique and evaluation of different PFMT strategies in perioperative period.

Impact of preoperative and postoperative membranous urethral length measured by 3 Tesla magnetic resonance imaging on urinary continence recovery after robotic-assisted radical prostatectomy

INTRODUCTION

We sought to investigate the impact of preoperative and postoperative membranous urethral length (MUL) on urinary continence using 3 Tesla (3T) magnetic resonance imaging (MRI) after robotic-assisted radical prostatectomy (RARP).

METHODS

Between 2008 and 2013, 190 men with RARP underwent preoperative and postoperative MRI. Patients who received adjuvant radiotherapy or who were lost to followup were excluded, leaving 186 patients eligible for analysis. Preoperative MUL was estimated from the prostate apex to the penile bulb, while postoperative MUL was estimated from the bladder neck to penile bulb. Patients with no pads or protection were considered to have complete continence. Logistic regression analysis was used to identify predictors associated with urinary incontinence at six and 12 months.

RESULTS

Age was commonly associated with urinary incontinence at six and 12 months. In addition, diabetes mellitus (DM) was another factor associated with urinary incontinence at 12 months. When adjusting these variables, preoperative MUL ≤16 mm (95% confidence interval [CI] 1.01-1.14; p=0.022), postoperative MUL ≤14 mm (95% CI 1.16-9.80; p=0.025) and percent change of MUL >18% (95% CI 1.17-7.23; p=0.021) were significantly associated with urinary incontinence at six months. However, at 12 months, preoperative MUL ≤13.5 mm (95% CI 1.85-19.21; p=0.003) and postoperative MUL ≤13 mm (95% CI 1.24-13.84; p=0.021) had impacts on urinary incontinence, but not percent change of MUL.

CONCLUSIONS

Preoperative and postoperative MUL were significantly associated with urinary continence recovery after RARP. Therefore, efforts to preserve MUL are highly recommended during surgery for optimal continence outcomes after RARP.

A prognostic model for predicting urinary incontinence after robot-assisted radical prostatectomy

BACKGROUND

The aim of this study is to develop a novel prognostic model for estimating the risk of postoperative urinary incontinence (UI) after robot-assisted radical prostatectomy (RARP).

METHODS

Participants comprised 131 men who underwent RARP at our hospital from 2011 to 2013. Cox regression analyses were performed to evaluate associations between UI and preoperative factors including filling cystometry and pressure-flow study results and magnetic resonance imaging.

RESULTS

Logistic regression analyses revealed significant associations between membranous urethral length or levator thickness and UI at 3 and 6 months. Stratification produced high (membranous urethral length < 9.5 mm or levator thickness < 9.0 mm) and low (membranous urethral length ≥ 9.5 mm and levator thickness ≥ 9.0 mm) UI risk groups. These inter-group differences in UI rate were significant.

CONCLUSIONS

We developed a novel prognostic model based on preoperative patient data that can be used for patient counselling.

The influence of membranous stretched urethral length and urethral circumference on postoperative recovery of continence after radical prostatectomy: A pilot study

INTRODUCTION

We investigate the influence of stretched membranous urethral length (SUL) and urethral circumference (UC) on postoperative recovery of continence after radical prostatectomy (RP).

METHODS

To evaluate the distal continence zone intraoperatively, we individually measured and recorded stretched membranous urethral length (distance between the urogenital diaphragm and the prostate apex with cephalad retraction, SUL) and urethral circumference (UC) after exposure of the urethra. We analyzed the association between magnetic resonance imaging-measured membranous urethral length (MRIL) and urethral diameter (MRID) and intraoperative SUL and UC and influence on return to continence.

RESULTS

The mean patient age, SUL and UC were 66.5 ± 6.0 years, 24.2 ± 3.3 mm, and 27.5 ± 4.4 mm, respectively. MRIL and MRID were 11.3 ± 1.6 mm and 10.6 ± 1.9mm, respectively. In the bivariate correlation analysis, there was no statistically significant correlation between SUL and MRIL (p = 0.201) and between UC and MRID (p = 0.124). In the Kaplan-Meier curve analysis, cumulative continence rates between the two groups dichotomized at the median value according to age (p = 0.0519), SUL (p = 0.6583), UC (p = 0.4031), MRIL (p = 0.4042), and MRID (p = 0.8191) were not significantly different. High SUL-to-MRIL ratio (>2.2) was the only significant predictor of lower cumulative continence rate (p = 0.0457).

CONCLUSIONS

MRIL measured during surgery was not associated with postoperative continence recovery after RP. We observed that an excessively long membranous urethra compared to the urethral length on preoperative MRI is predictive of poorer postoperative continence recovery. However, small sample size and potential confounding surgical factors limit the significance of this study.

A novel surgical technique for preserving the bladder neck during robot-assisted laparoscopic radical prostatectomy: preliminary results

PURPOSE

To describe our new surgical technique for preserving the bladder neck during robot-assisted laparoscopic prostatectomy (RALP) and to present the anatomy between the bladder neck and prostate.

METHODS

Between December 2012 and May 2014, 52 RALPs were performed at our institute. Demographic, perioperative, and postoperative data were recorded. Quality of life (QoL) scores were assessed before RALP, after urethral catheter removal, and at the first month after RALP. Fatty connective tissue between bladder neck and prostate was introduced, and circular muscle fibers of the internal sphincter were seen in all patients. Complications were classified according to the Clavien-Dindo classification. Statistical analyses were performed.

RESULTS

Mean follow-up was 9.6±5.2 months; mean age was 61.1±6.5 years. Our novel surgical technique for preserving the bladder neck was performed in 52 patients, and they were continent after catheter removal; mean duration of the catheter was 9.4±1.4 days. There was a significant difference in QoL before RALP and after catheter removal, however, but there was no statistical difference between before and 1 month after RALP (respectively; P<0.001, P=0.5). Furthermore, there was no complication related to the bladder neck such as bladder neck stricture, acute/chronic urinary retention, as well as no Clavien III, IV, and V complications. In addition, conventional laparoscopy and/or open surgery was not needed in any of the RALP cases.

CONCLUSION

Our novel technique provided very early continence at the time of catheter removal after RALP within short-term follow-up. This can help early recovery and develop QoL scores after RALP.

Current techniques to improve outcomes for early return of urinary continence following robot-assisted radical prostatectomy

Although open retropubic radical prostatectomy has been the most commonly used surgical technique for patients with localized prostate cancer for decades, robot-assisted radical prostatectomy (RARP) has recently become an alternative option and widely used in Japan as well as around the world. RARP has been shown to have higher postoperative continent rates than retropubic and laparoscopic radical prostatectomy; however, urinary incontinence has remained one of the most significant causes for concern among patients who seek surgical treatment for prostate cancer, even after the introduction of RARP. The literature has shown that certain technical modifications to improve urinary continence are advocated as potential aids to reduce the risk of urinary incontinence after RARP. These modifications might be divided into 3 categories to realize the improvement of early return of urinary continence after RARP: 1) preservation, 2) reconstruction, and 3) reinforcement of the anatomic structures in the pelvis, which will make a new supporting system after radical prostatectomy. In this review, we discuss the intraoperative techniques to improve outcomes for early return of urinary continence following RARP, and provide a critical summary of current knowledge on its outcome in the literature.

MRI findings of radiation-induced changes in the urethra and periurethral tissues after treatment for prostate cancer

PURPOSE

To assess radiotherapy (RT)-induced changes in the urethra and periurethral tissues after treatment for prostate cancer (PCa).

METHODS AND MATERIALS

This retrospective study included 108 men (median age, 64 years; range, 43-87 years) who received external-beam radiotherapy (EBRT) and/or brachytherapy for PCa and underwent endorectal-coil MRI of the prostate within 180 days before RT and a median of 20 months (range, 2-62 months) after RT. On all MRIs, two readers independently measured the urethral length (UL) and graded the margin definition (MD) of the urethral wall and the signal intensities (SIs) of the urethral wall and pelvic muscles on 4-point scales.

RESULTS

The mean urethral length decreased significantly from pre- to post-RT MRI (from 15.2 to 12.6mm and from 14.4 to 12.9 mm for readers 1 and 2, respectively; both p-values <0.0001). Brachytherapy resulted in greater urethral shortening than EBRT. After RT, SI in the urethral wall increased in 57% (62/108) and 35% (38/108) of patients (readers 1 and 2, respectively). The frequency and magnitude of SI increase in pelvic muscles depended on muscle location. In the obturator internus muscle, SI increased more often after EBRT than after brachytherapy, while in the periurethral levator ani muscle SI increased more often after brachytherapy than after EBRT.

CONCLUSION

After RT for PCa, MRI shows urethral shortening and increased SI of the urethral wall and pelvic muscles in substantial percentages of patients.