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The creation of synthetic reservoirs for bladder replacement has been limited by challenges of interfacing synthetic materials and native tissue. We sought to overcome this challenge by utilizing a novel bilayer silk fibroin scaffold (BLFS) as an intermediary towards the development of an acellular prosthetic reservoir.Under institutionally-approved protocols, 3D-printed reservoirs were implanted in six juvenile female pigs after cystectomy. BLFS was attached to the in-situ prosthetic reservoir serving as an intermediary to native ureteral and urethral tissue anastomoses. Our first protocol allowed four pigs to be survived up to seven days, and the second protocol allowed two pigs to be survived for up to one year. At the first sign of functional decline or the end of the study period, the animals were euthanized, and kidneys, ureters, prosthetic bladder, and urethra were harvested en-bloc for histopathology.The first two pigs had anastomotic urine leaks due to design flaws resulting in early termination. The third pig had acute renal failure resulting in early termination. The artificial bladder design was modified in subsequent iterations. The fourth pig survived for seven days and upon autopsy, had intact urethral and ureteral anastomoses. The fifth and sixth pigs survived for 11 and 12 weeks, respectively, before they were sacrificed due to failure to thrive. One animal developed an enteric fistula. The other animal had an intact anastomosis, and the BLFS was identified at the ureteral and urethral anastomoses on histopathogic analysis.Replacing the porcine bladder with a prosthetic bladder was successfully achieved for up to three months, the second longest survival period for a nonbiological bladder alternative. Bilayer silk fibroin scaffold was used for the first time to create an interface between synthetic material and biologic tissue by allowing ingrowth of urothelium onto the acellular alloplastic bladder.

INTRODUCTION AND OBJECTIVES Conventional renal stone dusting is challenging; the holmium laser (Ho:YAG) and holmium with MOSES Effect (Ho:YAG-MOSES) fail to uniformly produce fragments

Introduction: We sought to examine the intrarenal fluid and tissue temperature alterations during dusting and fragmentation with the thulium fiber laser (TFL) in an in vivo porcine kidney. Material...

Objective: It has been previously reported that warming irrigation fluid higher than body temperature may decrease ureteral spasm and thereby facilitate ureteroscopic access to the proximal ureter....

Introduction: The advent of single-use disposable flexible ureteroscopes allows for rapid prototyping of novel endoscopes. In this regard, we sought to develop a female-specific ureteroscope, with ...

Many major guidelines across the globe address the medical and surgical management of urolithiasis. We elected to compare and contrast the recommendations among the 5 most highly cited guidelines on stone disease to offer insights on where evidence has created a consensus and where there remains ongoing controversy and hence a need for the pursuit of studies that will provide a higher level of evidence.We reviewed the American Urological Association 2019 medical and 2016 surgical guidelines, the 2016 Canadian Urological Association guidelines, the 2020 European Association of Urology guidelines, the 2019 National Institute for Health and Care Excellence and the 2019 Urological Association of Asia guidelines. Tables correlating guideline statements by topic were created, and a comparative analysis was conducted to ascertain consensus and discordance.Comparative analysis of recommendations from the American Urological Association guidelines to the Canadian Urological Association, European Association of Urology, National Institute for Health and Care Excellence guidelines and Urological Association of Asia revealed a high consensus surrounding the medical management of stones. In terms of the surgical management of stones, there is high consensus regarding the treatment of ureteral stones including medical expulsive therapy using alpha blockers, not prestenting for uncomplicated ureteroscopy and employment of either ureteroscopy or shockwave lithotripsy as first line treatment. There is high consensus among the American Urological Association, European Association of Urology, National Institute for Health and Care Excellence and Urological Association of Asia guidelines regarding renal stone treatment. The Canadian Urological Association does not have guidelines on the management of renal stones. Unlike the American Urological Association and National Institute for Health and Care Excellence, the Canadian Urological Association and European Association of Urology make specific recommendations regarding selection of patients for shockwave lithotripsy procedures, including stone density, skin-to-stone distance, treatment rate, acoustic coupling and postshockwave lithotripsy use of medical expulsive therapy.There are many areas of consensus and only minor areas of conflict among the most up-to-date American Urological Association, Canadian Urological Association, European Association of Urology, National Institute for Health and Care Excellence and Urological Association of Asia guidelines on the medical and surgical management of stone disease. Conflicts among guidelines and areas of low evidence, such as followup imaging strategies and stone surveillance, the use of a ureteral access sheath in ureteroscopy and guidance on the use of miniaturized percutaneous nephrolithotomy, are opportunities for novel, impactful high grade clinical studies.

Computerized tomographic urography is the diagnostic tool of choice for evaluating hematuria. In keeping with the ALARA (As Low As Reasonably Achievable) principle, we evaluated a triple bolus computerized tomography protocol designed to reduce radiation exposure.Patients with macroscopic or microscopic hematuria were prospectively randomized to conventional computerized tomography (100) or triple bolus computerized tomography (100). The triple bolus computerized tomography protocol entails 2 scans: pre-contrast scan followed by 3 contrast injections at 40 seconds, 60 seconds and 20 minutes prior to the second scan to capture all 3 phases. The conventional computerized tomography protocol requires 4 scans: pre-contrast scan, and 3 post-contrast scans at the corticomedullary, nephrographic and excretory phases. Radiation exposure and the detection of urological pathology were recorded based on radiology reports.There were no differences in patient demographics or body mass index between the 2 groups. Triple bolus computerized tomography exposed patients to 33% less radiation (1,715 vs 1,145 mGy*cm for conventional vs triple bolus computerized tomography; p0.001). For macroscopic hematuria, the pathology detection rates were 70% for triple bolus and 73% for conventional computerized tomography (p=0.72). For microscopic hematuria, the detection rates were 59% for triple bolus and 50% for conventional computerized tomography (p=0.68). In both groups, the rates of detection of urolithiasis, renal cysts, urological masses, bladder pathology and prostate pathology were no different between triple bolus and conventional computerized tomography.In both the settings of macroscopic and microscopic hematuria evaluation, triple bolus computerized tomography significantly reduces radiation exposure while providing equivalent detection of genitourinary pathology compared to conventional computerized tomography. The ability to detect upper tract filling defects was not specifically tested.

Background The gold standard treatment for solitary medium-sized (1–2 cm) renal stones is not defined by recent guidelines, since management modalities including shockwave lithotripsy (SWL), retrograde intrarenal surgery (RIRS), and percutaneous nephrolithotomy (PNL) are recommended. Improved ability to predict patient outcomes would aid in patients’ counseling and decision-making. Objective To develop a nomogram predicting treatment failure, based on preoperative clinical variables, to be used in the preplanning setting. Design, setting, and participants We recruited 2605 patients from 14 centers and carried out a multicenter retrospective analysis of 699 SWL, 1290 RIRS, and 616 PN L procedures performed as first-line treatment for 1–2-cm kidney stones. The variables evaluated included age, gender, previous renal surgery, body mass index, stone size, location, stone density, skin-to-stone distance, presence of urinary tract infections (UTIs), and hydronephrosis. Outcome measurements and statistical analysis Multivariate logistic regression was fitted to predict treatment failure, defined as the presence of residual fragments >4 mm. A nomogram was developed based on the coefficients of the logit function. Results and limitations A total of 2431 (93.3%) patients were stone free; 174 (6.7%) treatment failures were recorded and considered the event to be predicted. On univariate analysis, type of procedure, preoperative hydronephrosis, stone density, stone location, and laterality turned out to be statistically significant. Skin-to-stone distance, UTIs, and previous renal surgery were predictors of failure on multivariate analysis. Each variable was given a score based on statistical relevance. The main limitation of the current study is its retrospective nature. Conclusions This nomogram provides a prediction of treatment failure and need of reintervention for medium-sized kidney stones. External validation is needed to determine its reproducibility and validity. Patient summary We developed a preoperative model of treatment outcomes for 1–2-cm kidney stones. Its application may assist urologists to counsel patients with regard to stone management modality.

INTRODUCTION AND OBJECTIVE:Computed tomography urography (CTU) is the diagnostic tool of choice for evaluating hematuria. In keeping with the ALARA (as low as reasonably achievable) principle, we e...

Percutaneous nephrolithotomy (PCNL) is the treatment of choice for kidney stones2 cm in size. Obtaining a nephrostomy tract to access the kidney is a key step in this procedure that ultimately determines the patient's outcome. We describe each step of the endoscopic guided approach to PCNL as performed at the University of California, Irvine. Each step of the endoscopic guided PCNL is described and depicted in the video. Surgical steps depicted in the video are from various recorded PCNL procedures from our institution. This guide outlines the indications, preoperative preparation, patient positioning, surgical steps, and postoperative care for patients undergoing PCNL using the endoscopic guided approach. Direct observation of nephrostomy puncture, tract dilation using the balloon, and passing of the Amplatz sheath allow for proper access to the kidney and lower risk of injury. By following this systematic module of endoscopic guided PCNL, a nephrostomy tract can be created and accessed under direct observation, facilitating the routine steps of PCNL.