AimsIntraurethral catheter balloon inflation is a substantial contributor to significant catheter-related urethral injury. A novel safety valve has been designed to prevent these balloon-inflation injuries. The purpose of this evaluation was to assess the cost-effectiveness of urethral catheterisation with the safety valve added to a Foley catheter versus the current standard of care (Foley catheter alone).Materials and methodsThe analysis was conducted from the UK public payer perspective on a hypothetical cohort of adults requiring transurethral catheterization. A decision tree was used to capture outcomes in the first 30 days following transurethral catheterization, followed by a Markov model to estimate outcomes over a person's remaining lifetime. Clinical outcomes included catheter balloon injuries [CBIs], associated short-term complications, urethral stricture disease, life years and QALYs. Health-economic outcomes included total costs, incremental cost-effectiveness ratio, net monetary benefit (NMB) and net health benefit.ResultsOver a person's lifetime, the safety valve was predicted to reduce CBIs by 0.04 per person and CBI-related short-term complications by 0.03 per person, and nearly halve total costs. The safety valve was dominant, resulting in 0.02 QALYs gained and relative cost savings of 93.19 pound per person. Probabilistic sensitivity analysis indicated that the safety valve would be cost-saving in 97% of simulations run versus standard of care.ConclusionsThe addition of a novel safety valve aiming to prevent CBIs during transurethral catheterization to current standard of care was estimated to bring both clinical benefits and cost savings.

Paediatric urinary catheters are often necessary in critical care settings or to address congenital anomalies affecting the urogenital system. Iatrogenic injuries can occur during the placement of such catheters, highlighting the need for a safety device that can function in paediatric settings. Despite successful efforts to develop devices that improve the safety of adult urinary catheters, no such devices are available for use with paediatric catheters. This study investigates the potential for utilising a pressure-controlled safety mechanism to limit the trauma experienced by paediatric patients during inadvertent inflation of a urinary catheter anchoring balloon in the urethra. Firstly, we establish a paediatric model of the human urethra using porcine tissue by characterising the mechanical and morphological properties of porcine tissue at increasing postnatal timepoints (8, 12, 16 and 30 weeks). We identified that porcine urethras harvested from pigs at postnatal week 8 and 12 exhibit morphological properties (diameter and thickness) that are statistically distinct from adult porcine urethras (postnatal week 30). We therefore utilise urethra tissue from postnatal week 8 and 12 pigs as a model to evaluate a pressure-controlled approach to paediatric urinary catheter balloon inflation intended to limit tissue trauma during inadvertent inflation in the urethra. Our results show that limiting catheter system pressure to 150 kPa avoided trauma in all tissue samples. Conversely, all of the tissue samples that underwent traditional uncontrolled urinary catheter inflation experienced complete rupture. The findings of this study pave the way for the development of a safety device for use with paediatric catheters, thereby alleviating the burden of catastrophic trauma and life changing injuries in children due to a preventable iatrogenic urogenital event.

Objectives To perform a multi-institutional investigation of incidence and outcomes of urethral trauma sustained during attempted catheterization. Patients & Methods A prospective, multi-center study was conducted over a designated 3-4 month period, incorporating seven academic hospitals across the UK and Ireland. Cases of urethral trauma arising from attempted catheterization were recorded. Variables included sites of injury, management strategies and short-term clinical outcomes. The catheterization injury rate was calculated based on the estimated total number of catheterizations occurring in each center per month. Anonymised data were collated, evaluated and described. Results Sixty-six urethral catheterization injuries were identified (7 centers; mean 3.43 months). The mean injury rate was 6.2 +/- 3.8 per 1000 catheterizations (3.18-14.42/1000). All injured patients were male, mean age 76.1 +/- 13.1 years. Urethral catheterization injuries occurred in multiple hospital/community settings, most commonly Emergency Departments (36%) and medical/surgical wards (30%). Urological intervention was required in 94.7% (54/57), with suprapubic catheterization required in 12.3% (n = 7). More than half of patients (55.56%) were discharged with an urethral catheter, fully or partially attributable to the urethral catheter injury. At least one further healthcare encounter on account of the injury was required for 90% of patients post-discharge. Conclusions This is the largest study of its kind and confirms that iatrogenic urethral trauma is a recurring medical error seen universally across institutions, healthcare systems and countries. In addition, urethral catheter injury results in significant patient morbidity with a substantial financial burden to healthcare services. Future innovation to improve the safety of urinary catheterization is warranted.

Introduction We aim to design a tool to assess the impact of recurrent urinary tract infection (rUTI) on quality of life (QoL) in adult women, given the notable absence of an established instrument for this purpose. Materials and methods Best practice guidelines in health-related survey design were reviewed. A literature review informed creation of an interview guide. Following ethical approval, 10 female patients (23-38 years) with rUTI were invited to participate in phase 1 of questionnaire design; all agreed. Individual semi-structured interviews were conducted exploring the impact of rUTI on patients' QoL. Interviews were repeated with 5 staff members (3 urology nurses and 2 consultant urologists). Responses were recorded and thematic analysis performed, to inform the design of a new questionnaire. A further 10 patients were recruited to assess feasibility of completion. Results All participants found available questionnaires unfit for assessment of rUTI-related QoL. Multiple themes emerged as integral to an rUTI questionnaire, including: frequency of UTIs, duration of symptoms, time to full recovery, specific symptoms of UTI, constitutional symptoms, impact on work/education, impact on leisure activities, impact on interpersonal relationships, impact on sexual relationships, psychological aspects and implications of treatment. Data saturation was reached. Based on responses, the Recurrent Urinary tract infection Health and Functional Impact Questionnaire (RUHFI-Q) was drafted, comprising 10 domains and 16 items. Conclusions We propose a novel self-administered questionnaire, the RUHFI-Q, as an instrument to standardize evaluation of the QoL impact of rUTI in a population of premenopausal women. Further validation studies are in progress.

Cryopreservation is required to preserve the native properties of tissue for prolonged periods of time. In this study, we evaluate the impact that 4 different cryopreservation protocols have on porcine urethral tissue, to identify a protocol that best preserves the native properties of the tissue. The cryopreservation protocols include storage in cryoprotective agents at -20 degrees C and -80 degrees C with a slow, gradual, and fast reduction in temperature. To evaluate the effects of cryopreservation, the tissue is mechanically characterised in uniaxial tension and the mechanical properties, failure mechanics, and tissue dimensions are compared fresh and following cryopreservation. The mechanical response of the tissue is altered following cryopreservation, yet the elastic modulus from the high stress, linear region of the Cauchy stress - stretch curves is unaffected by the freezing process. To further investigate the change in mechanical response following cryopreservation, the stretch at different tensile stress values was evaluated, which revealed that storage at -20 degrees C is the only protocol that does not significantly alter the mechanical properties of the tissue compared to the fresh samples. Conversely, the ultimate tensile strength and the stretch at failure were relatively unaffected by the freezing process, regardless of the cryopreservation protocol. However, there were alterations to the tissue dimensions following cryopreservation that were significantly different from the fresh samples for the tissue stored at -80 degrees C. Therefore, any study intent on preserving the mechanical, failure, and geometric properties of urethral tissue during cryopreservation should do so by freezing samples at -20 degrees C, as storage at -80 degrees C is shown here to significantly alter the tissue properties.

Symptomatic stress urinary incontinence (SUI) and pelvic organ prolapse (POP) refractory to conservative management with pelvic floor muscle training or vaginal pessaries may warrant surgical intervention with different forms of biologic or synthetic material. However, in recent years, several global regulatory agencies have issued health warnings and recalled several mesh products due to an increase in complications such as mesh erosion, infection, chronic pain, and perioperative bleeding. At present, current surgical treatment strategies for SUI and POP are aimed at developing biological graft materials with similar mechanical properties to established synthetic meshes, but with improved tissue integration and minimal host response. This narrative review aims to highlight recent studies related to the development of biomimetic and biologic graft materials as alternatives to traditional synthetic materials for SUI/POP repair in female patients. We also investigate complications and technical limitations associated with synthetic mesh and biological biomaterials in conventional SUI and POP surgery. Our findings demonstrate that newly developed biologic grafts have a lower incidence of adverse events compared to synthetic biomaterials. However there remains a significant disparity between success in preclinical trials and long-term clinical translation. Further characterization on the optimal structural, integrative, and mechanical properties of biological grafts is required before they can be reliably introduced into clinical practice for SUI and POP surgery. Impact statement Our review article aims to outline the clinical history of developments and controversies associated with the use of synthetic mesh materials in the surgical treatment of stress urinary incontinence and pelvic organ prolapse, as well as highlighting recent advancements in the area of biological graft materials and their potential importance in an area that remains an enduring issue for patients and clinicians alike. This article aims to provide a concise summary of previous controversies in the field of urinary incontinence, while evaluating the future of potential biomaterials in this field.

Acute epididymo-orchitis (AEO) is a common urological condition characterised by pain and swelling of the epididymis which can affect men of any age. The aetiology and to some extent the management of the patient differ between paediatric and young and older adult groups. A retrospective analysis was performed at the University Hospital Limerick from 2012 to 2016. Hospital In-Patient Enquiry (HIPE) data were obtained for all patients diagnosed with orchitis, epididymitis, epididymo-orchitis or testicular abscess over this 5-year period. 140 patients were identified, the age range was 0–89, median age 35.6. These were then split into 3 clinical groups, pre-pubertal (Group 1, 0–15-year-olds), sexually active young men (Group 2a, 16–35-year-olds) and men over 35 (Group 2b). Nine patients had an abscess on ultrasound investigation. There was a significant correlation between the presence of an abscess and the need for an orchidectomy (2 patients, P = 0.035). Two patients were reported as having an atrophic testis following AEO and both were in Group 2b. Overall, 7/131 (5

Introduction and objectives: Radical inguinal orchidectomy with ligation and division of the spermatic cord at the deep inguinal ring is the treatment of choice for testicular mass suspicious of cancer. In the era of organ preserving and minimally invasive surgery, it may be possible to propose a less radical sub-inguinal orchidectomy that may avoid the morbidity associated with opening the inguinal canal. The effect of this approach on oncological margins is not known. The aim of this article was to investigate the presence of spermatic cord involvement after a radical inguinal orchidectomy with a view to test feasibility of a modified sub-inguinal approach for testicular tumour excision. Materials and methods: A retrospective study on all orchidectomies performed for suspected testicular cancer was performed at a single hospital from over an 8-year period from January 2005 to December 2013. Non-cancerous lesions were excluded after histopathological review. All testicular malignancies were included and detailed histopathological review was performed. Results: A total of 121 orchidectomies were performed over the 8-year period. Three patients had spermatic cord involvement. Spermatic cord involvement did not adversely affect the outcome in these patients after a median follow-up of 5 years irrespective of tumour histology. The proximal spermatic cord was not involved in any testicular germ cell tumours on further cord sectioning, the only patient with proximal cord involvement had a B-cell lymphoma. Conclusion: We postulate that a sub-inguinal modified orchidectomy may be a less invasive alternative to radical inguinal orchidectomy, with comparable oncological outcomes based on low risk of spermatic cord involvement, which in itself is not a prognostic factor. We require further long-term follow-up studies on patients who have undergone this approach to validate the oncological outcomes and report the possible advantage of lower post-operative complications with this technique.

There are no prospective data describing the incidence and spectrum of long-term complications associated with traumatic urethral catheterisation (UC). We prospectively monitored the long-term clinical outcomes and complications of patients with traumatic UC injuries. A prospective study at two tertiary university hospitals was performed to record all referrals for iatrogenic urethral injuries caused by UC. Long-term follow-up was prospectively maintained by regular outpatient department visits and by monitoring all urological interventions and their outcomes from urinary catheter-related injuries. The incidence of traumatic UC was 13.4 per 1000 catheters inserted in male patients and 37 iatrogenic urethral injuries were recorded. The mean age was 74 ± 12 years and the mean length of follow-up was 37 ± 3.7 months. Urethral injuries were caused by inflating the catheter anchoring balloon in the urethra (n = 26) or by creating a false passage with the catheter tip (n = 11). In total, 29 patients (78%) developed urethral stricture disease during their follow-up; of which 11 have required at least one urethral dilation and two have required one urethrotomy. Three patients required long-term indwelling suprapubic catheter placement and seven patients opted for a long-term indwelling urethral catheter. There were eight patient mortalities; one of which was due to severe urosepsis resulting from catheter balloon inflation in the urethra. Catheter-related injuries are associated with significant long-term complications in this vulnerable patient cohort. In future, such injuries may be preventable if the safety profile of the urinary catheter is modified.

Background: There is a lack of data on urethral injuries due to misplaced urinary catheters in paediatric patients. Our aim was to characterise the mechanical and histological features of juvenile porcine urethras after catheter-induced urethral trauma. We also propose the porcine model as being mechanically representative of a paediatric urethra. An understanding of paediatric urethral properties and their responses to catheter trauma is a vital foundation in preventing iatrogenic catheter-related injuries. Methods: Juvenile porcine urethras of varying ages (n=23, age: 2–7 months) were obtained from an abattoir to evaluate their mechanical and histological properties. The 7-month porcine model is representative of an adult urethra and corresponding testing was performed in adult embalmed cadavers (n=7) and a Thiel cadaver to correlate human relevance with this porcine model. Paediatric porcine urethras were mounted onto an experimental apparatus designed to measure pressure and diameter changes in response to catheter induced trauma. Eight-, 10- and 12-Fr silicone urinary catheters were inserted into the 2-, 3- and 7-month porcine urethral models respectively and the anchoring balloon was intentionally inflated in the bulbar urethra with the relevant recommended inflation volume. Results: Catheter balloon inflation pressures for 8-, 10- and 12-Fr urinary catheters were 198, 160, 284, 421 and 450 kPa in 2-, 3-, 7-month Thiel cadaver and embalmed cadaver respectively. On histological analysis, tearing and rupture of pediatric porcine urethra were observed following catheter balloon inflation with disruption of complete collagen, elastin and muscle fibres. Conclusions: Seven-month-old porcine urethra models approximate the mechanical properties of the cadaveric urethras. Conversely, 2- and 3-month porcine urethras provide significantly less “resistance to expansion” compared to the 7-month model. Therefore, young porcine models can represent the mechanical properties of pediatric urethral tissue in the context of catheter associated urethral trauma.

Background Direct mechanical characterization of tissue is the application of engineering techniques to biological tissue to ascertain stiffness or elasticity, which can change in response to disease states. A number of papers have been published on the application of these techniques to prostate tissue with a range of results reported. There is a marked variability in the results depending on testing techniques and disease state of the prostate tissue. We aimed to clarify the utility of direct mechanical characterization of prostate tissue in identifying disease states. Methods A systematic review of the published literature regarding direct mechanical characterization of prostate tissue was undertaking according to PRISMA guidelines. Results A variety of testing methods have been used, including compression, indentation, and tensile testing, as well as some indirect testing techniques, such as shear-wave elastography. There is strong evidence of significant stiffness differences between cancerous and non-cancerous prostate tissue, as well as correlations with prostate cancer stage. There is a correlation with increasing prostate stiffness and increasing lower urinary tract symptoms in patients with benign prostate hyperplasia. There is a wide variation in the testing methods and protocols used in the literature making direct comparison between papers difficult. Most studies utilise ex-vivo or cadaveric tissue, while none incorporate in vivo testing. Conclusion Direct mechanical assessment of prostate tissue permits a better understanding of the pathological and physiological changes that are occurring within the tissue. Further work is needed to include prospective and in vivo data to aid medical device design and investigate non-surgical methods of managing prostate disease.

PURPOSEMany self-help guides advise patients that spreading fluid intake throughout the day can reduce overactive bladder symptoms. However, although animal studies suggest a link between a faster filling rate and increased afferent nerve firing, to our knowledge the relationship between the filling rate and bladder sensation has not been examined in humans. The aim of this study was to investigate the effect of bladder volume and the bladder filling rate on the bladder sensation and voiding patterns of patients with overactive bladder.MATERIALS AND METHODSA control group of 40 female volunteers were recruited by open advertisement. A further 24 female patients with overactive bladder were recruited from the urology outpatient department. Each participant completed the UDI-6 (Urinary Distress Inventory, Short Form), the IIQ-7 (Incontinence Impact Questionnaire, Short Form) and a 3-day sensation related bladder diary.RESULTSThe proportion of urgent voids in the control group increased with increasing voided volume and bladder filling rates (each p ≤0.001). The proportion of urgent voids in patients with overactive bladder also increased with increasing voided volume and bladder filling rates (p = 0.004 and 0.013, respectively). On regression analysis the rate of bladder filling was an independent predictor of urgent voids in patients with overactive bladder but not in the control group. Patients with overactive bladder were less tolerant of higher bladder filling rates and experienced most grades of bladder sensation at lower voided volumes and filling rates than the control group.CONCLUSIONSThe bladder filling rate appears to influence the intervoiding interval and the sensation associated with each void in patients with overactive bladder. Advising patients to lower the bladder filling rate should help reduce urinary frequency, urgency and urge incontinence.