MRI factors to predict urinary incontinence after retropubic/laparoscopic radical prostatectomy

The Association Between Low Preoperative Serum Testosterone and Post-radical Prostatectomy Urinary Function

OBJECTIVE

To determine if hypogonadism leads to delayed urinary function recovery post-radical prostatectomy (RP) by studying the effect of preoperative factors including age, membranous urethral length, radiation therapy, and Body Mass Index on urinary continence in patients with or without hypogonadism.

MATERIALS AND METHODS

We identified 1209 patients treated by RP with both pretreatment T and post-treatment urinary outcome. We assessed whether there was an association between low preoperative T level (prenoon T ≤ 300 ng/dL) and continence (using ≤1 pad/d) at 6 and 12months post-RP. Patient-reported continence was used when available, otherwise, surgeon-assessed continence was used. Logistic regression models were used, adjusted for age at RP and nerve-sparing status.

RESULTS

Median age at RP was 61 (Intraquatile Range (IQR) 56, 66), 92% of patients had at least one nerve spared and 99% were continent at baseline. Continence in patients with low T was nonsignificantly lower at 6months (odds ratio 0.69, 95% confidence interval 0.44, 1.06; P = .10) and nonsignificantly higher at 12months (odds ratio 1.07, 95% confidence interval 0.71, 1.58; P = .8). Sensitivity analyses excluding patients with preoperative metastasis or treated with androgen deprivation therapy (ADT) and including testosterone as a continuous predictor were consistent with the primary analysis; similarly finding no evidence of an association.

CONCLUSION

Although we cannot rule out an effect on early continence, overall the evidence does not suggest that low serum testosterone adversely impacts urinary function recovery after RP. This finding can be used to counsel patients enrolled in neoadjuvant ADT trials or those patients undergoing RP who have had prior ADT, such as in the setting of oligometastatic disease.

An artificial intelligence method for predicting postoperative urinary incontinence based on multiple anatomic parameters of MRI

Background

Deep learning methods are increasingly applied in the medical field; however, their lack of interpretability remains a challenge. Captum is a tool that can be used to interpret neural network models by computing feature importance weights. Although Captum is an interpretable model, it is rarely used to study medical problems, and there is a scarcity of data regarding MRI anatomical measurements for patients with prostate cancer after undergoing Robotic-Assisted Radical Prostatectomy (RARP). Consequently, predictive models for continence that use multiple types of anatomical MRI measurements are limited.

Methods

We explored the energy efficiency of deep learning models for predicting continence by analyzing MRI measurements. We analyzed and compared various statistical models and provided reference examples for the clinical application of interpretable deep-learning models. Patients who underwent RARP at our institution between July 2019 and December 2020 were included in this study. A series of clinical MRI anatomical measurements from these patients was used to discover continence features, and their impact on continence was primarily evaluated using a series of statistical methods and computational models.

Results

Age and six other anatomical measurements were identified as the top seven features of continence by the proposed model UINet7 with an accuracy of 0.97, and the first four of these features were also found by primary statistical analysis.

Conclusions

This study fills the gaps in the in-depth investigation of continence features after RARP due to the limitations of clinical data and applicable models. We provide a pioneering example of the application of deep-learning models to clinical problems. The interpretability analysis of deep learning models has the potential for clinical applications.

Prediction of recovery time of urinary incontinence following robot-assisted laparoscopic prostatectomy

OBJECTIVES

Postoperative urinary incontinence recovery following robot-assisted laparoscopic prostatectomy is an important outcome. We investigated whether factors that affect urinary incontinence can predict the duration of postoperative incontinence recovery.

METHODS

A total of 310 patients underwent robot-assisted laparoscopic prostatectomy. Continence recovery was defined as either pad-free or a safety pad only status. Univariate and multivariate analyses were performed on clinical variables to identify those that were associated with continence recovery. A scoring system to predict recovered continence was constructed using statistically significant variables. The validity of this tool was tested in a new cohort of 273 patients.

RESULTS

Factors associated with recovery of urinary incontinence were membranous urethral length, preservation of bilateral neurovascular bundles, and a preoperative Prostate Imaging Reporting and Data System score of ≥3 in the apex. Age was related only to incontinence recovery at 1 month. To prepare the score, weighting was performed using the estimated values. Using the developed scoring system, participants in the verification set were divided into three groups. The early recovery group had a median incontinence recovery of 4 (4-12) weeks, the medium recovery group, 12 (4-24) weeks, and the late recovery group, 24 (24-48) weeks, which was a significant difference (p < 0.001).

CONCLUSIONS

The applied scoring system based on preoperative factors related to incontinence and derived from patient groups was significantly associated with continence recovery time. In patients undergoing robot-assisted laparoscopic prostatectomy, our unit-weighted regression model of clinical variables can predict the duration of continence recovery.

A standardized method to measure the membranous urethral length (MUL) on MRI of the prostate with high inter- and intra-observer agreement

OBJECTIVES

The membranous urethral length (MUL), defined as the length between the apex and penile base as measured on preoperative prostate magnetic resonance imaging (MRI), is an important predictor for urinary incontinence after radical prostatectomy. Literature on inter- and intra - observer agreement of MUL measurement is limited. We studied the inter- and intra-observer agreement between radiologists using a well-defined method to measure the MUL on the prostate MRI.

METHODS

Prostate cancer patients underwent a preoperative MRI and robot-assisted radical prostatectomy (RARP) at one high-volume RARP center. MUL measurement was based on well-defined landmarks on sagittal T2-weighted (anatomical) images. Three radiologists independently performed MUL measurements retrospectively in 106 patients blinded to themselves, to each other, and to clinical outcomes. The inter- and intra-observer agreement of MUL measurement between the radiologists were calculated, expressed as intra-class correlation coefficient (ICC).

RESULTS

The initial inter-observer agreement was ICC 0.63; 95% confidence interval (CI) 0.28-0.81. Radiologist 3 measured the MUL mean 3.9 mm (SD 3.3) longer than the other readers, interpreting the caudal point of the MUL (penile base) differently. After discussion on the correct anatomical definition, radiologist 3 re-assessed all scans, which resulted in a high inter-observer agreement (ICC 0.84; 95% CI 0.66-0.91). After a subsequent reading by radiologists 1 and 2, the intra-observer agreements were ICC 0.93; 95% CI 0.89-0.96, and ICC 0.98; 95% CI 0.97-0.98, respectively. Limitation is the monocenter design.

CONCLUSIONS

The MUL can be measured reliably with high agreement among radiologists.

KEY POINTS

• After discussion on the correct anatomical definition, the inter- and intra - observer agreements of membranous urethral length (MUL) measurement on magnetic resonance imaging (MRI) were high. • A reproducible method to measure the MUL can improve the clinical usefulness of prediction models for urinary continence after RARP which may benefit patient counselling.

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.

The key role of levator ani thickness for early urinary continence recovery in patients undergoing robot-assisted radical prostatectomy: A multi-institutional study

BACKGROUND

Urinary continence (UC) recovery dramatically affects quality of life after robot-assisted radical prostatectomy (RARP). Membranous urethral length (MUL) has been the most studied anatomical variable associated with UC recovery.

OBJECTIVE

To investigate whether levator ani thickness (LAT), assessed with multi-parametric magnetic resonance imaging (mpMRI), correlates with UC recovery after RARP.

DESIGN, SETTING, AND PARTICIPANTS

The study included 209 patients treated with RARP by expert surgeons with extensive robotic experience from 2017 to 2019. All patients had complete, clinical, mpMRI, pathological, and postoperative data including pelvic floor muscle training (PFMT) protocols.

INTERVENTION

After a radiologist-specific training, two urologists independently examined the files, blinded to clinical and pathological findings as well as to postoperative continence status.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

On mpMRI, LAT, bladder neck (BN) shape, MUL, and apex overlapping (AO) were measured. UC recovery was defined as use of 0 or 1 safety pad at follow-up. Multivariable models were used to assess the association between variables and UC recovery.

RESULTS AND LIMITATIONS

Overall, 173 (82.8%) patients were continent after a median follow-up of 23 months (interquartile range [IQR]: 17-28). Of these, 98 (46.9%) recovered within 3 months after surgery, 42 (20.1%) from 3 to 6 months, and 33 (15.8%) from 6 months onwards. A significant higher rate of patients with LAT > 10 mm (88.1 vs.75.8%; p = 0.03) experienced UC recovery, compared to those with LAT < 10 mm. This difference was observed in the first 3 months after surgery. At multivariable analysis, LAT (odds ratio [OR]: 1.18, 95% confidence interval [CI]: 1.02-1.37; p = 0.02), Preoperative ICIQ score (OR: 0.91, 95% CI: 0.82-0.98, p = 0.03) and PFMT (OR: 1.98, 95% CI: 1.01-3.93; p = 0.04) independently predict higher UC recovery within 3 months, after accounting for age, BMI, preoperative PSA, D'Amico risk group, MUL, BN shape and AO.

CONCLUSIONS

LAT greater than 1 cm was associated with greater UC recovery. Specifically, LAT greater than 1 cm seems to be associated with higher UC rate at 3 months after RARP, compared to those with LAT < 1 cm.

PATIENT SUMMARY

Magnetic resonance features can help in predicting the risk of incontinence after robot-assisted radical prostatectomy and should be taken into account when counseling patients before surgery.

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.

Myosteatosis as a novel predictor of urinary incontinence after robot-assisted radical prostatectomy

OBJECTIVES

To evaluate the impact of sarcopenia and myosteatosis on urinary incontinence after prostatectomy.

METHODS

We retrospectively reviewed consecutive patients who underwent robot-assisted radical prostatectomy without nerve sparing between December 2012 and March 2019. Psoas muscle index and average total psoas density, which were measured on preoperative computed tomography images at level L3, were used to evaluate sarcopenia and myosteatosis, respectively. In addition, several magnetic resonance imaging variables associated with pelvic muscles, the urethra and the prostate were measured. Urinary continence was defined as non-use or use of just one incontinence pad per day. Logistic regression analyses aimed to identify the predictors of urinary incontinence 3 and 12 months after surgery.

RESULTS

Overall, 121 patients were included in the analysis. The incidence rates of urinary incontinence 3 and 12 months after surgery were 42% (51/121 cases) and 16% (19/121 cases), respectively. Logistic multivariable analysis showed that low average total psoas density was the only significant independent predictor of urinary incontinence 3 months after surgery (P < 0.01), and low obturator internus muscle thickness (P = 0.01), short membranous urethral length (P = 0.01) and low average total psoas density (P < 0.01) were significant independent predictors of urinary incontinence 12 months after surgery. By contrast, psoas muscle index was not statistically associated with urinary incontinence after surgery.

CONCLUSIONS

Myosteatosis (low average total psoas density) could be a novel predictor of urinary incontinence after robot-assisted radical prostatectomy.

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.

Patient- and Tumour-related Prognostic Factors for Urinary Incontinence After Radical Prostatectomy for Nonmetastatic Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

While urinary incontinence (UI) commonly occurs after radical prostatectomy (RP), it is unclear what factors increase the risk of UI development.

OBJECTIVE

To perform a systematic review of patient- and tumour-related prognostic factors for post-RP UI. The primary outcome was UI within 3 mo after RP. Secondary outcomes included UI at 3-12 mo and ≥12 mo after RP.

EVIDENCE ACQUISITION

Databases including Medline, EMBASE, and CENTRAL were searched between January 1990 and May 2020. All studies reporting patient- and tumour-related prognostic factors in univariable or multivariable analyses were included. Surgical factors were excluded. Risk of bias (RoB) and confounding assessments were performed using the Quality In Prognosis Studies (QUIPS) tool. Random-effects meta-analyses were performed for all prognostic factor, where possible.

EVIDENCE SYNTHESIS

A total of 119 studies (5 randomised controlled trials, 24 prospective, 88 retrospective, and 2 case-control studies) with 131 379 patients were included. RoB was high for study participation and confounding; moderate to high for statistical analysis, study attrition, and prognostic factor measurement; and low for outcome measurements. Significant prognostic factors for postoperative UI within 3 mo after RP were age (odds ratio [OR] per yearly increase 1.04, 95% confidence interval [CI] 1.03-1.05), membranous urethral length (MUL; OR per 1-mm increase 0.81, 95% CI 0.74-0.88), prostate volume (PV; OR per 1-ml increase 1.005, 95% CI 1.000-1.011), and Charlson comorbidity index (CCI; OR 1.28, 95% CI 1.09-1.50).

CONCLUSIONS

Increasing age, shorter MUL, greater PV, and higher CCI are independent prognostic factors for UI within 3 mo after RP, with all except CCI remaining prognostic at 3-12 mo.

PATIENT SUMMARY

We reviewed the literature to identify patient and disease factors associated with urinary incontinence after surgery for prostate cancer. We found increasing age, larger prostate volume, shorter length of a section of the urethra (membranous urethra), and lower fitness were associated with worse urinary incontinence for the first 3 mo after surgery, with all except lower fitness remaining predictive at 3-12 mo.

Anatomical predictors of long-term urinary incontinence after robot-assisted laparoscopic prostatectomy: A systematic review

AIMS

There is scarce evidence of anatomical risk factors that might affect long-term post-prostatectomy incontinence (PPI) in patients undergoing robot-assisted laparoscopic prostatectomy (RALP). This systematic review aims to identify anatomical measurements in preoperative magnetic resonance imaging (MRI) that might be associated with increased risk of urinary incontinence (UI) 1 year after RALP.

METHODS

A comprehensive search on Pubmed and Scopus databases up to November 2020 was performed. Eight articles met the inclusion criteria and were finally selected.

RESULTS

The selected studies included 1146 patients. Seven articles focused on membranous urethral length (MUL); all of them related MUL to long-term PPI in univariate analysis and five of them in multivariate analysis. Four studies presented MUL difference to measure the magnitude of the effect. Average MUL (mm) was 15.9 (SD, 2.6), 16.1 (95% confidence interval [CI]: 13.9-18.9), 12.1 (95% CI 9.7-14.9) and 14.5 in continent patients and 13.9 (SD, 2.9), 10 (95% CI: 8.7-12.1), 10.3 (95% CI: 8.7-12.4) and 9.3 in incontinent patients, with statistically significant differences in all cases. Five studies presented the odds ratio as a result; although there was substantial heterogeneity in the methods used to obtain it, there was consistency in finding an inverse association between MUL and PPI. Other measurements including prostatic-urethral angle, membranous urethral thickness, intraprostatic urethral length and intravesical prostatic protrusion have been reported in few studies, and no association with long-term PPI was found. Levator ani muscle thickness was related to long-term PPI in one article.

CONCLUSION

Greater MUL on preoperative MRI is associated with lower risk of UI 1 year after RALP.

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.

Significance of Membranous Urethral Length for Recovery From Postoperative Urinary Incontinence Following Holmium Laser Enucleation of the Prostate

PURPOSE

The aim of this study was to determine the significance of the membranous urethral length (MUL), including the thickness of the urethral sphincter, for recovery from postoperative stress urinary incontinence (SUI) following holmium laser enucleation of the prostate (HoLEP).

METHODS

We analyzed 78 patients who underwent HoLEP between June 2013 and September 2018, all of whom preoperatively received magnetic resonance imaging. MUL was measured using sagittal T2-weighted fast spin-echo images. The clinical and anatomical factors associated with MUL were evaluated. The recovery time of urinary incontinence was compared between patients with a long MUL (≥14 mm) and a short MUL (<14 mm). SUI included both stress and mixed urinary incontinence. Continence was defined as complete dryness.

RESULTS

The median MUL in patients without incontinence at 1 month postoperatively was significantly longer than the MUL in patients with incontinence (15.3 mm vs. 12.7 mm, P<0.001). The continence rates at 1 month after HoLEP in patients with longer MULs and shorter MULs were 80.4% and 30.0%, respectively. The recovery time of urinary incontinence in patients with longer MULs (≥14 mm) was significantly shorter than that in patients with shorter MULs (<14 mm) (log-rank test, P=0.001). After 6 months, the continence rates in patients with longer MULs and shorter MULs were similar (97%). MUL was significantly correlated with the recovery period of urinary incontinence (r=-0.459, P<0.001).

CONCLUSION

MUL was useful for predicting early recovery from urinary incontinence following HoLEP. This study provides evidence that postoperative urinary incontinence following a transurethral procedure for benign prostatic hyperplasia was associated with anatomical factors. A long MUL was associated with better tolerance to urinary sphincter damage by the transurethral procedure.

A novel tool to predict functional outcomes after robot-assisted radical prostatectomy and the value of additional surgery for incontinence

OBJECTIVES

To develop and validate a model to predict 12-month continence status after robot-assisted radical prostatectomy (RARP) from preoperative and 3-month postoperative data; this model could help in informing patients on their individualised risk of urinary incontinence (UI) after RP in order to choose the best treatment option.

PATIENTS AND METHODS

Data on 9421 patients in 25 Belgian centres were prospectively collected (2009-2016) in a compulsory regional database. The primary outcome was the prediction of continence status, using the International Consultation on Incontinence Urinary Incontinence Short Form (ICIQ-UI-SF) at 12-months after RARP. Linear regression shrinkage was used to assess the association between preoperative 3-month postoperative characteristics and 12-month continence status. This association was visualised using nomograms and an online tool.

RESULTS

At 12 months, the mean (sd) score of the ICIQ-UI-SF questionnaire was 4.3 (4.7), threefold higher than the mean preoperative score of 1.4. For the preoperative model, high European Association of Urology risk classification for biochemical recurrence (estimate [Est.] 0.606, se 0.165), postoperative radiotherapy (Est. 1.563, se 0.641), lower preoperative European Organisation for Research and Treatment of Cancer quality of life questionnaire 30-item core (EORCT QLQ-C30)/quality of life (QoL) score (Est. -0.011, se 0.003), higher preoperative ICIQ-UI-SF score (Est 0.214, se 0.018), and older age (Est. 0.058, se 0.009), were associated with a higher 12-month ICIQ-UI-SF score. For the 3-month model, higher preoperative ICIQ-UI-SF score (Est. 0.083, se 0.014), older age (Est. 0.024, se 0.007), lower 3-month EORCT QLQ-C30/QoL score (Est. -0.010, se 0.002) and higher 3-month ICIQ-UI-SF score (Est. 0.562, se 0.009) were associated with a higher 12-month ICIQ-UI-SF score.

CONCLUSIONS

Our models set the stage for a more accurate counselling of patients. In particular, our preoperative model assesses the risk of UI according to preoperative and early postoperative variables. Our postoperative model can identify patients who most likely would not benefit from conservative treatment and should be counselled on continence surgery.

Climacturia After Radical Prostatectomy: MRI-Based Predictors

BACKGROUND

After radical prostatectomy (RP), climacturia is a prevalent and distressing problem. To date, no specific predictors have been identified.

AIM

In this analysis, we sought to find associated pelvic magnetic resonance imaging (MRI) parameters.

METHODS

We identified all men in our departmental database who (i) had climacturia post-RP, ≥3 episodes; (ii) underwent a pre-RP endorectal MRI; (iii) had no radiation or androgen deprivation therapy (ADT). Soft tissue and bony dimensions were measured by 2 raters blinded to clinical and pathological data.

OUTCOMES

MRI parameters included the following: maximum height, width, and depth of prostate, prostate volume, urethral width and length, lower conjugate of pelvis, bony femoral width, outer and inner levator distances and thickness. Point-biserial correlations were run on univariate associations. Logistic regression was used for the multivariable model.

RESULTS

194 consecutive pre-RP MRI studies were reviewed (56 men with and 138 without climacturia). Mean age was 60 ± 7 years, average time post-RP at assessment, 7 ± 7 months. Of MRI parameters, urethral width (r = 0.13, P = .03) and lower conjugate (r = 0.12, P = .05) were associated with presence of persistent climacturia. 2 others met criteria for multivariable analysis, prostate depth and outer levator distance. Of the non-MRI parameters, none were significantly related to climacturia and only body mass index (BMI) met criteria for multivariable analysis. On multivariable analysis, only urethral width was associated with climacturia (OR = 1.23, 95% CI: 1.01-1.49, P = .04); the wider the urethra, greater the chance of climacturia.

CLINICAL IMPLICATIONS

Improved ability to predict the occurrence of orgasm-associated incontinence in the preoperative setting.

STRENGTHS AND LIMITATIONS

Limitations include the fact that the MRI endorectal probe may have distorted pelvic tissues during imaging and that our study population size was small. However, prospective data collection, blinded measurements by 2 trained readers, and rigorous statistical analysis should be considered strengths.

CONCLUSION

By identifying preoperative risk factors, such as urethral width on MRI, we may be able to better understand the pathophysiology of this condition and furthermore may permit us to better counsel men regarding this postoperative outcome. Sullivan JF, Ortega Y, Matsushita K, et al. Climacturia After Radical Prostatectomy: MRI-Based Predictors. J Sex Med 2020;17:1723-1728.

How can we prevent postprostatectomy urinary incontinence by patient selection, and by preoperative, peroperative, and postoperative measures? International Consultation on Incontinence-Research Society 2018

AIMS

To review current prevention strategies for urinary incontinence among patients undergoing radical prostatectomy (RP).

METHODS

This is a consensus report of the proceedings of a research proposal from the annual International Consultation on Incontinence-Research Society (ICI-RS), 14 to 16 June 2018 (Bristol, UK): "How can we prevent postprostatectomy incontinence by patient selection, and by preoperative, peroperative, and postoperative measures?"

RESULTS

Several baseline parameters were proposed as predicting factors for postprostatectomy urinary incontinence (PPUI), including age, tumor stage, prostate volume, preoperative lower urinary tract symptoms, maximum urethral closure pressure, and previous transurethral resection of the prostate. More recently, magnetic resonance imaging has been used to measure the membranous urethral length and sphincter volume. Peroperative techniques include preservative and reconstructive approaches. Bladder neck preservation improved early (6 months), as well as long-term (>12 months) continence rates. Several prospective studies have reported earlier return of continence following preservation of puboprostatic ligaments, although no long-term data are available. Preservation of the urethral length yielded controversial outcomes. Concerning postoperative strategies, it is probably optimal to remove the catheter in a window between 4 and 7 days if clinically appropriate; however, more research in this regard is still required. Postoperative PFME (preoperative pelvic floor muscle exercise) appears to speed up the recovery of continence after RP.

CONCLUSIONS

Conservative strategies to prevent PPUI include proper patient selection and PFME. Peroperative techniques have largely shown benefit in the short term. Postoperative complications and timing of trial without catheter can influence continence status. Future research initiatives must assess peroperative and postoperative measures, with longer-term follow-up.

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.

Correlation between lumbar skeletal muscle size and urinary incontinence after radical prostatectomy

OBJECTIVES

Urinary incontinence is a major concern after radical prostatectomy because it can decrease quality of life. The aim of the present study was to explore the effect of preoperative skeletal muscle on urinary quality of life after robot-assisted radical prostatectomy.

METHODS

A total of 762 patients underwent robot-assisted radical prostatectomy. Longitudinal health-related quality of life was evaluated using the Expanded Prostate Cancer Index Composite instrument. The skeletal muscle area at the level of the third lumbar vertebra was assessed preoperatively by computed tomography and was standardized to height to obtain the skeletal muscle index. Reduced skeletal muscle size (RSMS) was defined as a skeletal muscle index ≤ 53 or ≤ 43 cm² /m² in patients with a body mass index (BMI) ≥25 or < 25, respectively.

RESULTS

A total of 301 patients were included in this study, of whom 91 were classified as having RSMS (30.2%). Non-RSMS patients exhibited better urinary function at 12 months (P = .012) and better urinary continence recovery at 2 weeks and 12 months (P = .033 and P = .014, respectively) after prostatectomy compared with RSMS patients. Univariate and multivariate analyses identified preoperative RSMS as a significant and independent predictor of urinary incontinence (odds ratio = 1.77, P = .028).

CONCLUSIONS

Patients with RSMS had a lower urinary quality of life compared with non-RSMS patients after robot-assisted radical prostatectomy, and RSMS, independent of age or BMI, was predictive of postoperative urinary incontinence.

MRI of the Male Pelvic Floor

The pelvic floor is a complex structure that supports the pelvic organs and provides resting tone and voluntary control of the urethral and anal sphincters. Dysfunction of or injury to the pelvic floor can lead to gastrointestinal, urinary, and sexual dysfunction. The prevalence of pelvic floor disorders is much lower in men than in women, and because of this, the majority of the published literature pertaining to MRI of the pelvic floor is oriented toward evaluation of the female pelvic floor. The male pelvic floor has sex-specific differences in anatomy and pathophysiologic disorders. Despite these differences, static and dynamic MRI features of these disorders, specifically gastrointestinal disorders, are similar in both sexes. MRI and MR defecography can be used to evaluate anorectal disorders related to the pelvic floor. MRI can also be used after prostatectomy to help predict the risk of postsurgical incontinence, to evaluate postsurgical function by using dynamic voiding MR cystourethrography, and subsequently, to assess causes of incontinence treatment failure. Increased tone of the pelvic musculature in men secondary to chronic pain can lead to sexual dysfunction. This article reviews normal male pelvic floor anatomy and how it differs from the female pelvis; MRI techniques for imaging the male pelvis; and urinary, gastrointestinal, and sexual conditions related to abnormalities of pelvic floor structures in men.Online supplemental material is available for this article.^©RSNA, 2019.

Total anatomical reconstruction during robot-assisted radical prostatectomy: focus on urinary continence recovery and related complications after 1000 procedures

OBJECTIVES

To present the functional and oncological outcomes after ≥1 year of follow-up, following an experience of >1000 robot-assisted radical prostatectomies (RARPs) with our standardised total anatomical reconstruction (TAR) technique. To evaluate which factors influence postoperative continence recovery in order to obtain a nomogram to predict the risk of postoperative urinary incontinence (UI).

PATIENTS AND METHODS

The enrolment phase began in June 2013 and ended in May 2017. Patients were prospectively included in the study with the following inclusion criteria: (i) localised prostate cancer (clinical stages cT1-3, cN0, cM0); (ii) indication for RP; and (iii) preoperative multiparametric prostate magnetic resonance imaging. All patients underwent RARP with the TAR technique done at the end of the demolitive phase. The continence rates were assessed at 24 h, and 1, 4, 12, 24 and 48 weeks after catheter removal. Patients were defined as continent if they answered 'zero pad' or 'one safety pad' per day. A logistic regression model was used to evaluate the potential impact of some pre- and intraoperative factors on postoperative urinary continence recovery. Model discrimination was assessed using an area under (AUC) the receiver operating characteristic (ROC) curve. A nomogram to predict the risk of postoperative UI after RARP with the TAR technique was generated based on the logistic model.

RESULTS

In all, 1008 patients were enrolled in our study. At 24 h, and 1, 4, 12, 24 and 48 weeks after catheter removal, 621 (61.61%), 594 (58.93%), 803 (79.66%), 912 (90.48%), 950 (94.25%) and 956 (94.84%) patients were continent, respectively. In the logistic regression model, the variables analysed had a higher impact on continence recovery at 4 and 12 weeks. At 4 weeks, the postoperative odds of urinary continence recovery increased with the absence of diabetes [odds ratio (OR) 2.76, 95% confidence interval (CI) 1.41-5.41] and D'Amico low vs high risk (OR 2.01, 95% CI 1.01-3.99). At 12 weeks, urinary continence increased with the absence of diabetes (OR 3.01, 95% CI 1.23-7.35), D'Amico low vs high risk (OR 4.04, 95% CI 1.56-10.47), and D'Amico intermediate vs high risk (OR 3.33, 95% CI 1.66-6.70). ROC curves were drawn and an AUC value of 61.9% (95% CI 57.49-66.36) at 4 weeks and 63.8% (95% CI 58.03-69.65) at 12 weeks were computed. Based on these parameters, two nomograms (at 4 and 12 weeks postoperatively) were generated.

CONCLUSION

The TAR technique conferred excellent results in the early recovery of urinary continence. Two nomograms were created, to predict preoperatively the postoperative odds of urinary continence recovery at 4 and 12 weeks after RARP by integrating the presence of diabetes and D'Amico risk classification.

Pelvic magnetic resonance imaging parameters predict urinary incontinence after robot-assisted radical prostatectomy

OBJECTIVE

Urinary incontinence (UI) is a major prostate cancer (PCa) treatment-related morbidity. It has been reported that post-prostatectomy UI is related to the width of the pelvic floor muscles (PFM) and the length of the urethra. However, the details of these anatomical parameters are unknown. The aim of this study was to investigate whether preoperative pelvic parameters or anatomical parameters of the urethra, as measured by magnetic resonance imaging (MRI), are correlated with UI.

METHODS

Between 2010 and 2017, 571 patients with localized PCa underwent robot-assisted radical prostatectomy (RARP) at Okayama University Hospital. Patients treated by a single experienced surgeon were included in the study. Preoperative prostate volume, obturator internal muscle, anal sphincter muscle, levator ani muscle (LAM), urethra wall thickness (UWT), and membranous urethral length (MUL) were measured by MRI. Patients were divided into two groups depending on leakage status 1 year after RARP using Expanded Prostate Index Composite Item 1.

RESULTS

Seventy patients were included in this retrospective study. Based on leakage status, 37 and 33 patients were allocated to the no-leakage and leakage groups, respectively. There were significant differences between the two groups in age (P = 0.03), MUL (P < 0.001), UWT (P = 0.03), and LAM (P = 0.001). Multivariate logistic regression analyses revealed that MUL and LAM predicted UI 1 year after RARP.

CONCLUSIONS

Pelvic parameters measured by MRI before RARP may be useful in the prediction of UI. In particular, MUL and LAM can predict postoperative UI by strict definition.

Appropriate preoperative membranous urethral length predicts recovery of urinary continence after robot-assisted laparoscopic prostatectomy

PURPOSE

We investigated that preoperative membranous urethral length (MUL) would be associated with the recovery of urinary continence after robot-assisted laparoscopic prostatectomy (RALP).

PATIENTS AND METHODS

We studied 204 patients who underwent RALP between May 2013 and March 2016. All patients underwent pelvic magnetic resonance imaging (MRI) preoperatively to measure MUL. Urinary continence was defined as the use of one pad or less (safety pad). The 204 patients were divided into two groups: continence group, those who achieved recovery of continence at 3, 6, and 12 months after RALP, and incontinence group, those who did not. We retrospectively analyzed the patients in terms of preoperative clinical factors including age, body mass index (BMI), estimated prostate volume, neurovascular bundle salvage, history of preoperative hormonal therapy, and MUL.

RESULTS

The safety pad use rate was 69.6%, 86.9%, and 91.1% at 3, 6, and 12 months, respectively. On univariate and multivariate analyses, MUL were significant factors in every term of recovery of urinary continence in both groups. According to the receiver operating characteristic (ROC) curve analysis, the preoperative MUL that could best predict early recovery of urinary continence at 3 months after RALP was 12 mm.

CONCLUSIONS

We suggest that preoperative MUL > 12 mm would be a predictor of early recovery of urinary continence after RALP.

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.

Quantitative assessment of fascia preservation improves the prediction of membranous urethral length and inner levator distance on continence outcome after robot-assisted radical prostatectomy

AIMS

To determine whether preoperative prostate/pelvic anatomical structures and intraoperative fascia preservation (FP) predict continence recovery after robot-assisted radical prostatectomy (RARP).

METHODS

Between January 2012 and March 2016, 439 prostate cancer (PCa) patients with normal preoperative continence were retrospectively included. FP score was defined as the extent of FP from base to apex of the prostate, quantitatively assessed by the surgeon. Anatomical prostate structures were measured on endorectal preoperative Magnetic Resonance Imaging. The International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF) was used to assess urinary incontinence (UI). Cox analysis was used to determine predictive factors for early continence recovery. Finally a binary logistic regression analysis was performed to develop a risk calculator.

RESULTS

At a median follow up of 12.1 months 50.8% of men reported UI. In the Cox multivariate analysis longer membranous urethral length (MUL; P < 0.0001; OR 1.309; CI 1.211, 1.415) and shorter inner levator distance (ILD; P < 0.0001; OR 0.904; CI 0.85, 0.961) were predictors of earlier continence recovery. In the multivariate binary logistic regression analysis longer MUL (P < 0.0001; OR 1.565, CI 1.362, 1.798), shorter ILD (P < 0.0001; OR 0.819, CI 0.742, 0.904) and higher FP score (P = 0.024; OR 1.089, CI 1.011, 1.172) were independent predictors of continence outcome. The risk calculator predicted continence recovery between 1.3% and 99%.

CONCLUSIONS

Preoperative longer MUL and shorter ILD, but also intraoperative FP independently improve continence recovery after RARP. The risk calculator could be used to identify patients at high risk of UI.

Magnetic resonance imaging-guided functional anatomy approach to prostate brachytherapy

PURPOSE

To provide an MRI based functional anatomy guide to prostate brachytherapy.

METHODS AND MATERIALS

We performed a narrative review of periprostatic functional anatomy and the significance of this anatomy in prostate brachytherapy treatment planning.

RESULTS

MRI has improved delineation of gross tumor and critical periprostatic structures that have been implicated in toxicity. Furthermore, MRI has revealed the significant anatomic variants and the dynamic nature of these structures that can have significant implications for treatment planning and dosimetry.

CONCLUSIONS

The MRI-based functional anatomy approach to prostate brachytherapy takes into account extent of disease, its relation to the patient's individual anatomy, and functional baseline to optimize the therapeutic ratio of prostate cancer treatment.

Preoperative Membranous Urethral Length Measurement and Continence Recovery Following Radical Prostatectomy: A Systematic Review and Meta-analysis

CONTEXT

Membranous urethral length (MUL) measured prior to radical prostatectomy (RP) has been identified as a factor that is associated with the recovery of continence following surgery.

OBJECTIVE

To undertake a systematic review and meta-analysis of all studies reporting the effect of MUL on the recovery of continence following RP.

EVIDENCE ACQUISITION

A comprehensive search of PubMed, EMBASE, and Scopus databases up to September 2015 was performed. Thirteen studies comprising one randomized controlled trial and 12 cohort studies were selected for inclusion.

EVIDENCE SYNTHESIS

Four studies (1738 patients) that reported hazard ratio results. Every extra millimeter (mm) of MUL was associated with a faster return to continence (hazard ratio: 1.05; 95% confidence interval [CI]: 1.02-1.08, p<0.001). Eleven studies (6993 patients) reported the OR (OR) for the return to continence at one or more postoperative time points. MUL had a significant positive effect on continence recovery at 3 mo (OR: 1.08, 95% CI: 1.03-1.14, p=0.004), 6 mo (OR: 1.12, 95% CI: 1.09-1.15, p<0.0001). and 12 mo (OR: 1.12, 95% CI: 1.03-1.22, p=0.006) following surgery. After adjusting for repeated measurements over time and studies with overlapping data, all OR data combined indicated that every extra millimeter of MUL was associated with significantly greater odds for return to continence (OR: 1.09, 95% CI: 1.05-1.15, p<0.001).

CONCLUSIONS

A greater preoperative MUL is significantly and positively associated with a return to continence in men following RP. Magnetic resonance imaging measurement of MUL is recommended prior to RP.

PATIENT SUMMARY

We examined the effect that the length of a section of the urethra (called the membranous urethra) had on the recovery of continence after radical prostatectomy surgery. Our results indicate that measuring the length of the membranous urethra via magnetic resonance imaging before surgery may be useful to predict a longer period of urinary incontinence after surgery, or to explain a delay in achieving continence after surgery.