Striated Urethral Sphincter Research Articles

Ultrasound-Based Prognostic Anatomical Parameters for Post-Prostatectomy Incontinence: A Systematic Review

Background: A number of assessment methods for the pelvic floor have been described. Male pelvic floor ultrasound is an accessible, noninvasive assessment tool. Objective: To evaluate current published literature on anatomical parameters on pre- and postoperative ultrasound imaging of the male pelvic floor and correlation with continence status following radical prostatectomy (RP). Methods: A comprehensive literature search was conducted using the PRISMA guidelines to identify publications up to November 2022. Exclusion criteria consisted of animal studies, non-English articles, case reports, reviews and abstracts or reports from conferences. A full-text review was performed on 12 papers using ultrasound to assess pelvic floor anatomy and correlation with continence status following RP. Results: A total of 18 anatomical parameters were evaluated using US. Membranous urethral length (MUL), striated urethral sphincter (SUS) morphology and activation were most commonly studied. Shorter pre- and postoperative MUL, decreased preoperative SUS thickness and vascularity, postoperative discontinuity of SUS muscle fibres and decreased SUS activation are associated with post-prostatectomy incontinence (PPI). There is a paucity of data comparing anatomical changes in men prior to and following RP. The benefits of transperineal ultrasound are that it is minimally invasive, accessible, provides dynamic imaging of all three striated muscle complexes simultaneously and includes a bony landmark to reference measures of pelvic floor muscle displacement. Conclusions: Ultrasound evaluation of the male pelvic floor is an evolving field as there is development in technology and understanding of pelvic floor anatomy. It is an accessible and dynamic imaging modality, which allows both morphological and functional assessment of pelvic floor anatomy and its role in PPI. MUL and SUS morphology and activation are associated with continence status following RP. Several other anatomical parameters that may predict PPI were identified. Current literature is limited by small, single-centre studies with heterogeneous cohorts and methodologies.

Pelvic Floor Muscle Function and Its Relationship with Post-Prostatectomy Incontinence

ObjectivesPost-prostatectomy incontinence (PPI) is a common condition, but the underlying mechanisms are not completely understood. Transperineal ultrasound (TPUS) assessment of voluntary pelvic floor muscle (PFM) function may be associated with PPI. This study investigates the relationship between PPI and pre- and postoperative displacement of anatomical landmarks related to PFM function.MethodsThis was a prospective longitudinal cohort study of 40 patients undergoing robotic-assisted radical prostatectomy (RARP) by a high-volume single surgeon. All patients underwent PFM training pre- and postoperatively. TPUS was used to obtain sagittal images of pelvic structures during maximal voluntary PFM contractions: (1) preoperatively, (2) 3 weeks postoperatively, and (3) 6 weeks postoperatively. TPUS images were analyzed to calculate displacement of anatomical landmarks associated with activation of striated urethral sphincter (SUS), bulbocavernosus muscle (BC), and puborectalis muscle (PR). Continence was assessed at 3 and 6 weeks postoperatively, defined as use of ≤ 1 pad/day. The relationship of continence to the displacement of SUS, BC, and PR was analyzed.ResultsSUS, BC, and PR displacement decreased significantly 3 weeks postoperatively (P = 0.042, P = 0.002, P < 0.001, respectively). Continent men exhibited significantly greater SUS displacement (median, 5.13 mm) than incontinent men (median, 3.90 mm) 3 weeks postoperatively (P = 0.029). Between 3 and 6 weeks following RARP, there was significant increase in SUS, BC, and PR displacement (P = 0.003, P = 0.030, P < 0.001, respectively).ConclusionsA significant decrease in PFM function occurs following RARP, with a subsequent recovery of postoperative PFM function between 3 and 6 weeks post-procedure in men who undergo PFM training. SUS activation was significantly greater in continent patients compared to incontinent patients at 3 weeks following RARP.

The relationship between pre- and postprostatectomy measures of pelvic floor muscle function and development of early incontinence after surgery.

The aim of this study is to investigate (i) whether pelvic floor muscle (PFM) shortening can be enhanced by provision of training focused on striated urethral sphincter (SUS) with feedback before prostatectomy, (ii) whether PFM shortening during voluntary efforts and coughing before and after prostatectomy differs between men who do and do not report symptoms of urinary incontinence 1 month after prostatectomy, and (iii) the relationship between severity of incontinence after prostatectomy and features of pelvic floor function (muscle shortening) and urethral length before and after prostatectomy. Sixty men referred for preoperative PFM training before radical prostatectomy participated. The International Continence Society Male Short Form questionnaire was used to quantify continence status. Transperineal ultrasound (US) imaging was used to record pelvic displacements related to activation of striated urethral sphincter, bulbocavernosus (BC) and puborectalis muscles during cough, "natural" voluntary contraction following pamphlet instruction, and trained voluntary contraction after formal physiotherapist instruction including US feedback. Pelvic floor displacements following training differed between continent and incontinent men; continent participants demonstrated increased SUS shortening after training (compared with "natural"), but no difference was observed between trained and "natural" contractions for incontinent participants. Motion at ano-rectal junction during cough was reduced following surgery, but voluntary and involuntary activation of SUS or BC was not consistently affected by surgery. Participants' capacity to improve function of the SUS with training appears related to postprostatectomy continence outcome.

Evaluation of pelvic floor muscle elasticity in patients with overactive bladder syndrome using real-time tissue elastography

Introduction and hypothesisThe purpose of this study was to compare the muscle elasticity of the striated urethral sphincter (SUS) using real-time tissue elastography (RTE) as an evaluation of pelvic floor muscle (PFM) function between overactive bladder (OAB) patients and healthy women. MethodsThe subjects were 8 healthy middle-aged women (healthy group; age range 57–65 years) and 9 female OAB patients (OAB group; age range 42–80 years). The target sites of elastography were the striated urethral sphincter (SUS) and adipose tissue as the reference site; muscle elasticity was calculated as the strain ratio (SR) of the SUS to the reference site. Evaluations were performed at rest and during PFM contraction. The OAB group completed OAB symptom and quality of life questionnaires. The SUS SR was compared between the groups. The SUS SR at rest and during PFM contraction was compared within groups using the t-test and Wilcoxon’s test. The relationship between the questionnaire results and the SUS SR was evaluated by correlation analysis. ResultsIntergroup comparisons between the healthy and OAB groups showed no significant differences in SUS SR at rest and during PFM contraction. On intragroup comparisons, the SUS SR was significantly higher during PFM contraction than at rest in the healthy group (p = 0.011); in the OAB group, there was no significant difference in the SUS SR between rest and PFM contraction. The SUS SR was not significantly correlated with questionnaire results for OAB symptoms. ConclusionThis study shows the potential to non-invasively confirm the inability of OAB patients to correctly perform PFM contraction using RTE.

Examination of pelvic floor muscle elasticity in patients with interstitial cystitis/bladder pain syndrome using real-time tissue elastography.

The aim was to compare pelvic floor muscle (PFM) elasticity between interstitial cystitis/bladder pain syndrome (IC/BPS) patients and healthy women using real-time tissue elastography. The subjects were 17 IC/BPS female patients (IC/BPS group; age 34-84years), 10 healthy middle-aged women (middle-aged group; 50-80 years), and 17 healthy young adult women (young group; 23-37 years). The target sites of elastography were the striated urethral sphincter (SUS) and adipose tissue as the reference site; muscle elasticity was calculated as the strain ratio (SR) of the SUS to the reference site. Evaluations were performed at rest and during PFM contraction. The IC/BPS group completed lower urinary tract symptom and pain questionnaires. SUS SR was compared among the three groups. SUS SR at rest and during PFM contraction was compared among the three groups with the t-test and the Wilcoxon test. Associations between questionnaire results and SUS SR were evaluated by correlation analysis. There was no significant difference in age between the IC/BPS and middle-aged groups, but the young group was significantly younger than the other groups (p < 0.001). SUS SR at rest was significantly higher in the IC/BPS group than in the middle-aged (p = 0.014) and young groups (p = 0.002). Furthermore, in the IC/BPS group, there was no significant difference in SUS SR between at rest and during PFM contraction. SUS SR was not significantly correlated with questionnaire results for lower urinary tract symptoms. SUS SR at rest was significantly higher in the IC/BPS group than in the young and middle-aged groups.

Delivery of human mesenchymal adipose-derived stem cells restores multiple urological dysfunctions in a rat model mimicking radical prostatectomy damages through tissue-specific paracrine mechanisms.

Urinary incontinence (UI) and erectile dysfunction (ED) are the most common functional urological disorders and the main sequels of radical prostatectomy (RP) for prostate cancer. Mesenchymal stem cell (MSC) therapy holds promise for repairing tissue damage due to RP. Because animal studies accurately replicating post-RP clinical UI and ED are lacking, little is known about the mechanisms underlying the urological benefits of MSC in this setting. To determine whether and by which mechanisms MSC can repair damages to both striated urethral sphincter (SUS) and penis in the same animal, we delivered human multipotent adipose stem cells, used as MSC model, in an immunocompetent rat model replicating post-RP UI and ED. In this model, we demonstrated by using noninvasive methods in the same animal from day 7 to day 90 post-RP injury that MSC administration into both the SUS and the penis significantly improved urinary continence and erectile function. The regenerative effects of MSC therapy were not due to transdifferentiation and robust engraftment at injection sites. Rather, our results suggest that MSC benefits in both target organs may involve a paracrine process with not only soluble factor release by the MSC but also activation of the recipient's secretome. These two effects of MSC varied across target tissues and damaged-cell types. In conclusion, our work provides new insights into the regenerative properties of MSC and supports the ability of MSC from a single source to repair multiple types of damage, such as those seen after RP, in the same individual.

Pattern of activation of pelvic floor muscles in men differs with verbal instructions.

To investigate the effect of instruction on activation of pelvic floor muscles (PFM) in men as quantified by transperineal ultrasound imaging (US) and to validate these measures with invasive EMG recordings. Displacement of pelvic floor landmarks on transperineal US, intra-abdominal pressure (IAP) recorded with a nasogastric transducer, and surface EMG of the abdominal muscles and anal sphincter were recorded in 15 healthy men during sub-maximal PFM contractions in response to different verbal instructions: "tighten around the anus," "elevate the bladder," "shorten the penis," and "stop the flow of urine." In three men, fine-wire EMG recordings were made from puborectalis and bulbocavernosus, and trans-urethral EMG recordings from the striated urethral sphincter (SUS). Displacement data were validated by analysis of relationship with invasive EMG. Displacement, IAP, and abdominal/anal EMG were compared between instructions. Displacement of pelvic landmarks correlated with the EMG of the muscles predicted anatomically to affect their locations. Greatest dorsal displacement of the mid-urethra and SUS activity was achieved with the instruction "shorten the penis." Instruction to "elevate the bladder" induced the greatest increase in abdominal EMG and IAP. "Tighten around the anus" induced greatest anal sphincter activity. The pattern of urethral movement measured from transperineal US is influenced by the instructions used to teach activation of the pelvic floor muscles in men. Efficacy of PFM training may depend on the instructions used to train activation. Instructions that optimize activation of muscles with a potential to increase urethral pressure without increasing abdominal EMG/IAP are likely ideal. Neurourol. Urodynam. 35:457-463, 2016. © 2015 Wiley Periodicals, Inc.

Dynamics of male pelvic floor muscle contraction observed with transperineal ultrasound imaging differ between voluntary and evoked coughs

Coughing provokes stress urinary incontinence, and voluntary coughs are employed clinically to assess pelvic floor dysfunction. Understanding urethral dynamics during coughing in men is limited, and it is unclear whether voluntary coughs are an appropriate surrogate for spontaneous coughs. We aimed to investigate the dynamics of urethral motion in continent men during voluntary and evoked coughs. Thirteen men (28-42 years) with no history of urological disorders volunteered to participate. Transperineal ultrasound (US) images were recorded and synchronized with measures of intraabdominal pressure (IAP), airflow, and abdominal/chest wall electromyography during voluntary coughs and coughs evoked by inhalation of nebulized capsaicin. Temporal and spatial aspects of urethral movement induced by contraction of the striated urethral sphincter (SUS), levator ani (LA), and bulbocavernosus (BC) muscles and mechanical aspects of cough generation were investigated. Results showed coughing involved complex urethral dynamics. Urethral motion implied SUS and BC shortening and LA lengthening during preparatory and expulsion phases. Evoked coughs resulted in greater IAP, greater bladder base descent (LA lengthening), and greater midurethral displacement (SUS shortening). The preparatory inspiration cough phase was shorter during evoked coughs, as was the latency between onset of midurethral displacement and expulsion. Maximum midurethral displacement coincided with maximal bladder base descent during voluntary cough, but followed it during evoked cough. The data revealed complex interaction between muscles involved in continence in men. Spatial and temporal differences in urethral dynamics and cough mechanics between cough types suggest that voluntary coughing may not adequately assess capacity of the continence mechanism.

Urinary continence in laparoscopic radical prostatectomy with bladder neck preservation

To assess the effect of bladder neck preservation (BNP) on postoperative continence during laparoscopic radical prostatectomy. One hundred and forty-five patients with localized prostate cancer (Tlb-T2c) underwent laparoscopic radical prostatectomy in our center from July 2006 to May 2010, including 59 cases treated with bladder neck preservation (BNP group) and 86 cases with bladder neck resection (non-BNP group). All cases were diagnosed as prostate cancer by transrectal ultrasonography-guided prostate biopsy preoperatively, in which localized tumors were confirmed by CT or MRI and distant metastases were ruled out by ECT bone scan. All patients had no history of incontinence and no radiation therapy preoperatively. All the 145 operations were performed by the same surgeon. The bladder neck preservation was defined as a procedure of direct suturing of the bladder neck on the urethra without repair and reconstruction of the bladder neck. Both procedures of neurovascular bundle preservation and external striated urethral sphincter preservation were carried out on all cases. Urinary continence was evaluated using the International Continence Society questionnaire at 1, 3 and 6 months postoperatively. Positive surgical margins rates were compared between the two groups. Postoperative continence was defined as the absence of need for pads or the use of one pad daily. At 1, 3 and 6 months, the urinary continence rates were 42.4%, 74.6% and 86.4% in BNP group, respectively, while 25.6%, 58.1% and 80.2% in non-BNP group, respectively. There were statistically significant differences in continence at 1 and 3 months between two groups (P <0.05), while no significant differences were observed at 6 months postoperatively (P=0.331). There were no significant differences in overall rate of positive surgical margins between two groups (10.1% Compared with 10.4% P=0.954) and both groups had one case with positive surgical margins at bladder neck. Bladder neck preservation during laparoscopic radical prostatectomy is helpful for postoperative continence without increase of positive surgical margins rate.

A New Method to Quantify Male Pelvic Floor Displacement From 2D Transperineal Ultrasound Images

To develop a method to quantify displacement of pelvic structures during contraction of the pelvic floor muscles from transperineal ultrasound images in men and investigate the reliability of the method between days. Ten healthy male volunteers (aged 28-41 years) attended 2 separate data collection sessions. Ultrasound images were recorded during voluntary pelvic floor muscle contractions in cine-loop (video) format with the transducer aligned in the midsagittal plane on the perineum. Five anatomic points were defined to represent contraction from striated urethral sphincter (SUS), levator ani (LA), and bulbocavernosus (BC) muscles. Displacement of each point was calculated between the relaxed and contracted-state images. Intraclass correlation coefficient (ICC) values were calculated from displacement data to assess reliability of the method between days. Displacements of the 5 anatomic points closely matched predictions based on anatomic considerations of the male pelvic musculature. ICC values for displacement data calculated from 1, 2, and 3 repetitions ranged between 0.82 and 0.95 for ICC (2,1), 0.85 and 0.97 for ICC (2,2), and 0.86 and 0.97 for ICC (2,3), respectively. The new method reliably calculates displacements of points previously validated for women (ano-rectal junction and bladder base) in addition to new measures of muscle actions (SUS and BC) specific to men. Future use might include assessment of clinical populations to understand how these displacements relate to symptoms of incontinence.

Activation of the striated urethral sphincter to maintain continence during dynamic tasks in healthy men

Function of the striated urethral sphincter (SUS) in men is debated. Current evidence is limited to electromyographic (EMG) recordings made with concentric needle electrodes in supine. Understanding of SUS function requires investigation of SUS EMG activity using new recording techniques in dynamic tasks. The aim of this study was to evaluate timing and amplitude of SUS EMG at rest and during dynamic tasks that challenge continence by increasing intra-abdominal pressure (IAP). Investigative study of five healthy men aged 25-39 years. Measurements included SUS, anal sphincter (AS), and transversus abdominus (TrA) EMG, and IAP (recorded with a nasogastric pressure catheter). Participants performed four tasks that challenged postural control in standing (single and repetitive arm movement, stepping and load catching). IAP amplitude and SUS activity were linearly correlated during repetitive arm movement (R(2): 0.67-0.88). During stepping SUS EMG onset preceded the IAP increase, but followed it with rapid arm movements. When the trunk was loaded unpredictably onset of SUS generally followed the increase in IAP. The modest sample size meant only younger men were tested. Future studies might investigate healthy older men or those with certain pathologies. Data show that SUS activity increases proportionally with IAP. This provided evidence that SUS contributes to continence when IAP is increased, and that postural control of the trunk involves activation of this muscle.

Effect of renal pelvic and ureteral distension on the striated urethral sphincter with recognition of the "reno-vesico-sphincteric reflex".

Renal pelvic and ureteral distension occurs in physiologic (diuresis) and pathologic (calculus) conditions. Its effect on the vesical and posterior urethral pressures as well as on the electromyographic (EMG) activity of the striated urethral sphincter (SUS) was investigated. The renal pelvis of 10 healthy volunteers (7 men, 3 women; mean age 35.8+/-8.6 years) was distended by means of a 4-F balloon-tipped catheter in increments of 2 ml of saline up to 10 ml and the response of the vesical and posterior urethral pressures and SUS EMG activity was recorded. The test was repeated with ureteral distension in increments of 0.25 ml up to 1 ml. The response of the aforementioned parameters was also registered after anesthetization of the renal pelvis, ureter and SUS. Two rates of renal pelvic and ureteral distension were tested: rapid (1 ml/s) and slow (1 ml/min). Renal pelvic distension with large volumes effected an increase of the renal pelvic and urethral pressures (P < 0.05, P < 0.05, respectively), a vesical pressure drop (P < 0.05) and increased EMG activity of the SUS. Ureteral distension caused a rise of ureteral and urethral pressures as well as of SUS EMG activity. With rapid distension, the aforementioned parameters responded at smaller volumes than with slow distension. Renal pelvic, ureteral or SUS anesthetization effected no urethral or SUS EMG response. It is suggested that the reaction of above parameters to distension indicates a mechanism regulating the urine flow so as to protect the renal pelvis and the ureter from being overloaded. The vesical pressure drop with increased SUS EMG activity on renal pelvis distension postulates a reflex relationship that we call the "reno-vesico-sphincteric reflex". The role of this reflex in urine transport requires further study.

Prostate Shape, External Striated Urethral Sphincter and Radical Prostatectomy: The Apical Dissection

In an anatomical study of 64 gross specimens the external striated urethral sphincter was reconfirmed to extend as a single unit from the proximal penile urethra to the bladder base. The configuration of the external striated urethral sphincter was variable and was related to the shape of the apical prostate. Two basic prostatic shapes were recognized, distinguished by the presence or absence of an anterior apical notch. Whether a notch existed depended upon the degree of lateral lobe development and the position of its anterior commissure.In radical prostatectomy knowledge of the variation in the shape of the prostatic apex can help the surgeon to achieve optimal urethral transection with maximal preservation of the external striated urethral sphincter and other tissues of the continence mechanism. (J. Urol., 138: 543–550, 1987)

484 - Prostate Shape, External Striated Urethral Sphincter, and Radical Prostatectomy: The Apical Dissection

484 - Prostate Shape, External Striated Urethral Sphincter, and Radical Prostatectomy: The Apical Dissection

The Striated Muscle of the Prostate

No AccessJournal of Urology1 Feb 1966The Striated Muscle of the Prostate Charles B. Manley Charles B. ManleyCharles B. Manley More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(17)63439-6AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail © 1966 by The American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetailsCited ByKoraitim M (2018) The Male Urethral Sphincter Complex Revisited: An Anatomical Concept and its Physiological CorrelateJournal of Urology, VOL. 179, NO. 5, (1683-1689), Online publication date: 1-May-2008.BURNETT A and MOSTWIN J (2018) IN SITU ANATOMICAL STUDY OF THE MALE URETHRAL SPHINCTERIC COMPLEX: RELEVANCE TO CONTINENCE PRESERVATION FOLLOWING MAJOR PELVIC SURGERYJournal of Urology, VOL. 160, NO. 4, (1301-1306), Online publication date: 1-Oct-1998.Elbadawi A, Mathews R, Light J and Wheeler T (2018) IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL STUDY OF RHABDOSPHINCTER COMPONENT OF THE PROSTATIC CAPSULEJournal of Urology, VOL. 158, NO. 5, (1819-1828), Online publication date: 1-Nov-1997.Hammerer P, Michl U, Meyer-Moldenhauer W and Huland H (2018) Urethral Closure Pressure Changes with Age in MenJournal of Urology, VOL. 156, NO. 5, (1741-1743), Online publication date: 1-Nov-1996.Graversen P, England D, Madsen P and Bruskewitz R (2018) Significance of Striated Muscle in Curettings of the ProstateJournal of Urology, VOL. 139, NO. 4, (751-753), Online publication date: 1-Apr-1988.Myers R, Goellner J and Cahill D (2018) Prostate Shape, External Striated Urethral Sphincter and Radical Prostatectomy: The Apical DissectionJournal of Urology, VOL. 138, NO. 3, (543-550), Online publication date: 1-Sep-1987.Yalla S, Fam B, Gabilondo F, Jacobs S, Di Benedetto M, Rossier A and Gittes R (2018) Anteromedian External Urethral Sphincterotomy: Technique, Rationale and ComplicationsJournal of Urology, VOL. 117, NO. 4, (489-493), Online publication date: 1-Apr-1977.Andersen J, Bourne R and Bradley W (2018) Combined Electromyography and Gas Urethral Pressure Profilometry Before and After Transurethral Resection of the ProstateJournal of Urology, VOL. 116, NO. 5, (622-625), Online publication date: 1-Nov-1976.Bradley W and Timm G (2018) Combined Electromyographic and Gas Urethral Pressure ProfilometryJournal of Urology, VOL. 115, NO. 4, (433-434), Online publication date: 1-Apr-1976.Schellhammer P, Hackler R and Bunts R (2018) External Sphincterotomy: An Evaluation of 150 Patients with Neurogenic BladderJournal of Urology, VOL. 110, NO. 2, (199-202), Online publication date: 1-Aug-1973.Albers D, Faulkner K, Cheatham W, Elledge E and Coalson R (2018) Surgical Anatomy of the Pubovesical (Puboprostatic) LigamentsJournal of Urology, VOL. 109, NO. 3, (388-392), Online publication date: 1-Mar-1973.Hutch J and Rambo O (2018) A New Theory of the Anatomy of the Internal Urinary Sphincter and the Physiology of Micturition III. Anatomy of the UrethraJournal of Urology, VOL. 97, NO. 4, (696-704), Online publication date: 1-Apr-1967.Hutch J (2018) A New Theory of the Anatomy of the Internal Urinary Sphincter and the Physiology of Micturition IV. The Urinary Sphincteric MechanismJournal of Urology, VOL. 97, NO. 4, (705-712), Online publication date: 1-Apr-1967. Volume 95Issue 2February 1966Page: 234-240 Advertisement Copyright & Permissions© 1966 by The American Urological Association Education and Research, Inc.MetricsAuthor Information Charles B. Manley More articles by this author Expand All Advertisement Loading ...