SciCombinator

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Journal: BJU international

77

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WHAT’S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The sensitivity of the foreskin and its importance in erogenous sensitivity is widely debated and controversial. This is part of the actual public debate on circumcision for non-medical reason. Today some studies on the effect of circumcision on sexual function are available. However they vary widely in outcome. The present study shows in a large cohort of men, based on self-assessment, that the foreskin has erogenous sensitivity. It is shown that the foreskin is more sensitive than the uncircumcised glans mucosa, which means that after circumcision genital sensitivity is lost. In the debate on clitoral surgery the proven loss of sensitivity has been the strongest argument to change medical practice. In the present study there is strong evidence on the erogenous sensitivity of the foreskin. This knowledge hopefully can help doctors and patients in their decision on circumcision for non-medical reason. OBJECTIVES: To test the hypothesis that sensitivity of the foreskin is a substantial part of male penile sensitivity. To determine the effects of male circumcision on penile sensitivity in a large sample. SUBJECTS AND METHODS: The study aimed at a sample size of ≈1000 men. Given the intimate nature of the questions and the intended large sample size, the authors decided to create an online survey. Respondents were recruited by means of leaflets and advertising. RESULTS: The analysis sample consisted of 1059 uncircumcised and 310 circumcised men. For the glans penis, circumcised men reported decreased sexual pleasure and lower orgasm intensity. They also stated more effort was required to achieve orgasm, and a higher percentage of them experienced unusual sensations (burning, prickling, itching, or tingling and numbness of the glans penis). For the penile shaft a higher percentage of circumcised men described discomfort and pain, numbness and unusual sensations. In comparison to men circumcised before puberty, men circumcised during adolescence or later indicated less sexual pleasure at the glans penis, and a higher percentage of them reported discomfort or pain and unusual sensations at the penile shaft. CONCLUSIONS: This study confirms the importance of the foreskin for penile sensitivity, overall sexual satisfaction, and penile functioning. Furthermore, this study shows that a higher percentage of circumcised men experience discomfort or pain and unusual sensations as compared with the uncircumcised population. Before circumcision without medical indication, adult men, and parents considering circumcision of their sons, should be informed of the importance of the foreskin in male sexuality.

Concepts: Foreskin, Penis, Circumcision, Glans penis, Masturbation, Frenulum of prepuce of penis, Phimosis, Foreskin restoration

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What’s known on the subject? and What does the study add? Transurethral resection of the prostate (TURP) remains the dominant and definitive treatment for lower urinary tract symptoms due to benign prostatic hyperplasia (LUTS-BPH), but the widespread use of medical therapies (particularly monotherapies) for rapid symptom improvement has meant that the most common indication for TURP has shifted to moderate-severe medical therapy refractory LUTS to, coupled with abnormal objective parameters, or when complications arise. Patients undergoing TURP as part of contemporary randomised controlled trials are not older but have a larger preoperative prostate volume and reduced major morbidity compared with large cohort studies from successive past eras. Delayed surgery because of prolonged medical monotherapy may explain a higher reported failure to void rate, possibly because of negative impact on detrusor function from unrelieved obstruction. This study examined contemporary TURP for significant changes, specifically regarding prostate size, operative parameters, and outcomes, compared with two preceding decades. Electronic databases PubMed, EMBASE & Cochrane collaboration were searched for English literature on prospective randomized controlled trials, published between 1997 and 2007 using keywords “transurethral resection” and “prostate”. Monopolar TURP (M-TURP) cohort data of each study were selectively pooled for analysis, weighting studies according to patient numbers. Where possible, pooled post-operative outcomes data were compared with two large cohort landmark studies of successive preceding decades. A total of 3470 patients from 67 studies were included. Mean patient age (67 years) was unchanged, while mean pre-operative prostate volume of 47.6 g was greater than previously reported. Mean resected prostate tissue (25.8 g) with a resection time of 38.5 minutes suggested improved resection efficiency. A statistically significantly reduced transfusion rate and increased urinary tract infection (UTI) rate were reported. Hospital stay (3.6 days) and initial catheterisation duration (2.5 days) were similar, but post-operative urinary retention rate was slightly higher (6.8%). Contemporary RCTs of M-TURP showed larger prostate volume, and reduced major morbidity, compared with large cohort studies from successive past eras. The higher reported failure to void rate, may possibly reflect worse detrusor function at time of TURP. Delaying surgery by prolonged medical monotherapy may compound this. Trials methodology in this area requires quality improvement and standardisation in future.

Concepts: Cohort study, Urinary tract infection, Randomized controlled trial, Urology, Benign prostatic hyperplasia, Prostate, Prostatic stent, Transurethral microwave thermotherapy

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What’s known on the subject? and What does the study add? The association between Peyronie’s disease (PD) and erectile dysfunction (ED) is reported to be 20-70%. Frequently, men who suffer from both ED and PD do not respond to erectogenic medication. In such cases, a simple straightening operation does not provide any benefit to the patient, as inadequate rigidity still impedes sexual intercourse. For these patients, surgical correction of the curvature should be performed with simultaneous penile prosthesis implantation. Penile prosthesis implantation guarantees a functional straight penis. Almost all patients report adequate rigidity for sexual intercourse postoperatively; however, in up to 50% of cases, patients are dissatisfied with the postoperative penile length. In cases of penile prosthesis implantation for PD, a simultaneous penile lengthening procedure should be performed to increase postoperative satisfaction rates. We report our experience using a novel method for restoration of penile length and girth in patients with PD by grafting. Our study shows that penile prosthesis implantation with concomitant penile lengthening and girth restoration based on circumferential tunica albuginea incision is highly effective for extensive penile shaft reconstruction to correct severe penile shortening and narrowing, resulting in maximum penile length gain and girth restoration, regardless of plaque characteristics.

Concepts: Sexual intercourse, Andrology, Erectile dysfunction, Penis, Peyronie's disease, Penile prosthesis, Erection, Human penis size

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OBJECTIVE: To develop and test the safety and feasibility of a novel anti-biofilm mechanism configured for wireless capsule endoscopy (WCE) in a sheep bladder model. MATERIALS AND METHODS: A WCE mechanism, designed for long-term bladder monitoring, was developed and introduced into a sheep bladder for 5 months. The transparency of the surface was assessed by evaluating a resolution target placed inside the capsule at serial intervals using cystoscopy under general anaesthesia. Animal behaviour, voiding patterns and urine cultures were monitored throughout the study. At study termination, the capsule was extracted and assessed using scanning electron microscopy. RESULTS: The resolution target was visualized clearly at all investigation points. No notable adverse effects were noted during the entire follow-up period and no urinary tract infection occurred. Scanning electron microscopy confirmed the efficacy of the technology to prevent biofilm formation and surface encrustation. CONCLUSIONS: We report a novel technology that effectively prevents biofilm formation on the outer surface of foreign objects in the urinary tract. Further studies are under way to test the applicability of this technology in bladder WCE to enable high-quality wireless image transmission.

Concepts: Kidney, Urinary tract infection, Urine, Urinary bladder, Urinary system, Urethra, Scanning electron microscope, Endoscopy

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What’s known on the subject? and What does the study add? Chronic urinary retention (CUR) is a poorly defined entity, as the key element of definition, significant postvoid residual urine volume (PVR), has not a worldwide and moreover evidenced-based definition. There is no agreement on which is the threshold value to define a significant PVR and different society produced guidelines with different thresholds ranging from 300 mL to 1000 mL. Diagnosis is difficult, and management has not been defined yet. There is a lack of studies on the best management of these patients, as this group of patients has always been considered at high risk of failure. Only one study compares conservative with the surgical management but it is not a randomised controlled trail. This review offers a systematic appraisal of the most recent publications on CUR. It indicates the absence of a real worldwide agreed definition, as the two keys element of it are not satisfactorily defined yet: significant PVR, is suffering from a lack of evidenced-based definition, and percussable or palpable bladder is a very nebulous concept as it is not a criteria of certainty as different individual variables affect it. This has an important effect on management which is not structured. Most of the trials involving benign prostatic hyperplasia treatments (either medical or surgical) tend to exclude this group of patients, which is a clinically important group, comprising up to a quarter of men undergoing TURP in the UK. Urinary retention describes a bladder that does not empty completely or does not empty at all. Historically, urinary retention has been classified as either acute or chronic the latter is generally classified as high pressure or low pressure according to the bladder filling pressure on urodynamic. A MEDLINE® search for articles written in English and published before January 2010 was done using a list of terms related to urinary retention: ‘urinary retention’, ‘chronic urinary retention’ and ‘PVR’. Chronic urinary retention (CUR) is defined by the International Continence Society as ‘a non-painful bladder, which remains palpable or percussable after the patient has passed urine’. Abrams was the first to choose a residual urine volume >300 mL to define CUR as he considered it the minimum volume at which the bladder becomes palpable suprapubically. The UK National Institute for Health and Clinical Excellence lower urinary tract symptoms (LUTS) guidelines define CUR as a postvoid residual urine volume (PVR) of >1000 mL. No studies have specifically addressed the problem of quantifying the minimum amount of urine present in the bladder to define CUR. Nor did we find any publications objectively assessing at what amount of urine a bladder can be palpable. The ability to feel a bladder may rely on variables (i.e. medical skills and patient habitus). There is a marked variability of PVR, so the test should be repeated to improve precision. As defining CUR is difficult, structured management is challenging. Nearly all prospective trials exclude men with CUR from analysis, possibly anticipating a poor outcome and a high risk of complications. However, men with CUR are a clinically important group, comprising up to 25% of men undergoing transurethral resection of the prostate. Definition of CUR is imprecise and arbitrary. Most studies seem to describe the condition as either a PVR of >300 mL in men who are voiding, or >1000 mL in men who are unable to void. This confusion leads to an inability to design and interpret studies; indeed most prospective trials simply exclude these patients. There is a clear need for internationally accepted definitions of retention to allow both treatment and reporting of outcomes in men with LUTS, and for such definitions to be used by all investigators in future trials.

Concepts: Urine, Urology, Urinary bladder, Urinary system, Ureter, Urinary retention, Prostatic stent

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WHAT’S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Despite high morbidities, TURP is still considered as the ‘gold standard’ for treatment of BPH. Photoselective vaporization of the prostate (PVP) is a promising technique that is emerging as a possible alternative to TURP. However, there remains some debate about the advantages of PVP over TURP and whether PVP will be able to replace TURP as the first-line surgical treatment. We conducted a meta-analysis of recent papers on this subject and herein provide the overall efficacy and safety of PVP for treatment of BPH. OBJECTIVE: To assess the overall efficacy and safety of photoselective vaporization of the prostate (PVP) vs transurethral resection of the prostate (TURP) for treating patients with lower urinary tract symptoms (LUTS) secondary to benign prostate hyperplasia (BPH). PATIENTS AND METHODS: A systematic search of the electronic databases, including MEDLINE, Embase, Web of Science and The Cochrane Library, as well as manual bibliography searches were performed. The pooled estimates of maximum flow rate (Q(max) ), postvoid residual (PVR), quality of life (QoL), International Prostate Symptom Score (IPSS), operation duration, blood loss, catheterization time, hospital stay, capsule perforation, transfusion, transurethral resection (TUR) syndrome, urethral stricture and reintervention were calculated. RESULTS: At the 3-month follow-up, there was no significant difference in Q(max) , PVR, QoL and IPSS between the TURP and PVP groups. At the 6-month follow-up, the pooled QoL favoured TURP, but there was no significant difference in the other variables between the two groups. PVP was associated with less blood loss, transfusion, capsular perforation, TUR syndrome, shorter catheterization time and hospital stay, but longer operation duration and higher reintervention rate. CONCLUSIONS: The efficacy of PVP was similar to that of TURP in relation to Q(max) , PVR, QoL and IPSS, and it offered several advantages over TURP. As a promising minimal invasive technique, PVP could be used as an alternative surgical procedure for treating BPH.

Concepts: Blood, Evidence-based medicine, Urology, Urethra, Benign prostatic hyperplasia, International Prostate Symptom Score, Prostatic stent, Transurethral microwave thermotherapy

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OBJECTIVE: The male refractory period (MRP) continues to be a topic of discussion and debate within the field of sexual medicine. To date explanations rely on central descending (efferent) influences involving specific neurotransmitter systems. Herein we explore the issue of the male refractory period, identifying problems with current explanations, specifying the parameters of an adequate model, and suggesting possible mechanisms mediating this phenomenon. METHODS: We review the literature regarding existing explanations for the MRP and look to other systems of physiological regulation that might provide a model for the conceptualization of the MRP. RESULTS: Our approach differs from traditional explanations in that it emphasizes the possible roles of various peripheral, rather than central, feedback (afferent) systems that affect peripheral autonomic functioning and response. Yet our approach is consistent with other peripheral regulatory feedback systems controlling autonomic response related to such processes as heart rate, respiration, and gut motility. CONCLUSION: Although direct empirical research supporting our approach is lacking, sufficient evidence exists to support the idea that such processes are not only possible but likely with respect to the male refractory period. We suggest several lines of research that might provide empirical support for this approach.

Concepts: Physiology, Avicenna, Neuroscience, Ontology, Idea, Empirical research, Peripheral nervous system, Refractory period

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OBJECTIVES: To identify how many patients with symptoms of pure stress urinary incontinence (SUI) do not require any surgical treatment on the basis of urodynamics (UDS) and how many patients still do not require surgery 1 year after UDS. To assess the outcomes of these patients at 12-month follow-up. PATIENTS AND METHODS: Women with pure SUI received UDS and were prospectively divided into four groups, comprising women with: urodynamic stress incontinence (USI); detrusor overactivity (DO); USI + DO; and inconclusive UDS. Women with USI underwent a Tension Free Vaginal Tape (Obturator) (TVT-O) procedure (Gynecare; Ethicon Inc., Somerville, NJ, USA), whereas women with DO ±/- USI were recommended 24-week antimuscarinic therapy. Follow-up was scheduled at 3 and 12 months. To define subjective outcomes, all patients completed the International Consultation on Incontinence Questionnaire - short form, the Patient Global Impression - Improvement and the Urinary Distress Inventory. Patients were considered cured if they presented a negative stress test, a score reduction of at least 80% on the Urinary Distress Inventory and a response of ‘much better’ or ‘very much better’ on the Patient Global Impression - Improvement. RESULTS: Of the 263 women with pure SUI, 74.5% had a urodynamic diagnosis of USI, 10.6% had DO, 8% had USI + DO and 6.8% had inconclusive UDS. At 12-month follow-up, 165/181 (91.6%) women in group 1 were considered cured post-TVT-O; in the other groups, 33/67 (49.2%) patients were considered cured simply as a result of taking antimuscarinics; 13 of these 67 patients required TVT-O. CONCLUSIONS: UDS is able to show that several patients with symptoms of pure SUI present an underlying DO and do not require surgery, even 1 year after UDS. In these patients, antimuscarinic treatment appears to ensure a good rate of cure; thus, UDS could lead to the avoidance of several surgical procedures.

Concepts: Patient, Hospital, Surgery, Urology, Urinary incontinence, Physician, Urinary bladder, Ethicon Inc.

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WHAT’S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The AMS 800 urinary control system is the gold standard for the treatment of urinary incontinence due to sphincter insufficiency. Despite excellent functional outcome and latest technological improvements, the revision rate remains significant. To overcome the shortcomings of the current device, we developed a modern electromechanical artificial urinary sphincter. The results demonstrated that this new sphincter is effective and well tolerated up to 3 months. This preliminary study represents a first step in the clinical application of novel technologies and an alternative compression mechanism to the urethra. OBJECTIVES: To evaluate the effectiveness in continence achievement of a new electromechanical artificial urinary sphincter (emAUS) in an animal model. To assess urethral response and animal general response to short-term and mid-term activation of the emAUS. MATERIALS AND METHODS: The principle of the emAUS is electromechanical induction of alternating compression of successive segments of the urethra by a series of cuffs activated by artificial muscles. Between February 2009 and May 2010 the emAUS was implanted in 17 sheep divided into three groups. The first phase aimed to measure bladder leak point pressure during the activation of the device. The second and third phases aimed to assess tissue response to the presence of the device after 2-9 weeks and after 3 months respectively. Histopathological and immunohistochemistry evaluation of the urethra was performed. RESULTS: Bladder leak point pressure was measured at levels between 1091 ± 30.6 cmH(2) O and 1244.1 ± 99 cmH(2) O (mean ± standard deviation) depending on the number of cuffs used. At gross examination, the explanted urethra showed no sign of infection, atrophy or stricture. On microscopic examination no significant difference in structure was found between urethral structure surrounded by a cuff and control urethra. In the peripheral tissues, the implanted material elicited a chronic foreign body reaction. Apart from one case, specimens did not show significant presence of lymphocytes, polymorphonuclear leucocytes, necrosis or cell degeneration. Immunohistochemistry confirmed the absence of macrophages in the samples. CONCLUSIONS: This animal study shows that the emAUS can provide continence. This new electronic controlled sequential alternating compression mechanism can avoid damage to urethral vascularity, at least up to 3 months after implantation. After this positive proof of concept, long-term studies are needed before clinical application could be considered.

Concepts: Urine, Urinary incontinence, Anatomical pathology, Urinary bladder, Urinary system, Urethra, Urination, Urethral sphincter