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Ureteral obstruction is a prevalent urological condition associated with significant complications. The purpose of our study was to assess the safety and efficacy of a novel self-expanding, large caliber, biocompatible polymer-coated ureteral stent (Allium) for the treatment of ureteral obstructions. We conducted a retrospective analysis of data from patients who underwent Allium ureteral stent placement at our institute between November 2018 and May 2023. Demographic, clinical, and perioperative parameters were collected and analyzed. Logistic regression analyses were performed to identify preoperative factors predicting Allium stent migration. The study cohort comprised 30 patients who received a total of 40 successfully implanted Allium stents. No significant adverse events related to the insertion procedure were observed. During a median follow-up period of 29 months (range: 1–60 months), migration occurred in 11 (27.5%) stents while encrustation was noted in 8 (20%) stents. The median functional duration of the Allium stents was found to be 22 months (range:1–60 months), with an overall functioning rate at last follow-up being recorded as 59.5%. Multivariate analysis revealed that the glomerular filtration rate of the ipsilateral kidney was the sole risk factor predictive of Allium stent migration. With its minimal invasiveness and good tolerability, the Allium stent represents a safe and viable management option for treating ureteric obstructions; however, it should not be considered as definitive treatment but rather as an alternative option for patients unwilling or unsuitable for definitive treatment, particularly high-risk individuals or elderly patients exhibiting decreased ipsilateral glomerular filtration rates. [ABSTRACT FROM AUTHOR]

Purpose: To assess the effectiveness and pain intensity associated with magnetic ureteral stent removal using a retriever, without the aid of ultrasound guidance. Methods: We prospectively enrolled 100 patients who underwent retrograde rigid and flexible ureterorenoscopy with or without laser lithotripsy for ureteronephrolithiasis treatment from September 2021 to June 2023. These patients were assigned in two groups. Group 1 underwent the traditional ureteral stent insertion, while Group 2 underwent magnetic ureteral stent insertion. Both insertion and removal times were documented. The indwelling time for ureteral stents was 14 days. One group underwent stent removal via flexible cystoscopy using grasping forceps and the other group using just a magnetic retriever, without the aid of ultrasound guidance. The numeric pain rating scale, recommendation rate, and a standardized self-answered ureter stent symptoms questionnaire (USSQ) were obtained directly after stent removal. Results: Both groups presented comparable characteristics in factors such as age, body mass index, history of stone treatments, procedure type, and complication rates during and post-surgery. Time taken for ureteral stent insertion did not differ significantly between the groups (131.2 seconds for Group 1 vs 159.1 seconds for Group 2). However, the stent removal time (152.1 seconds for Group 1 vs 35.4 seconds for Group 2) and pain intensity (6 for Group 1 vs 2 for Group 2) were significantly lower for Group 2. Furthermore, five out of the six sections of the USSQ showed significantly better results for Group 2. Conclusions: The use of magnetic ureteral stents, as a safe and efficient alternative to conventional ureteral stents, not only eliminates the need for cystoscopy but also conserves resources and reduces patient discomfort. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of oral theophylline on stent-related syndrome (SRS) after Double-J insertion. Background: Double-J stent is widely using in many urological procedures. Infection, hematuria, and discomfort are some of common complication after stenting. Theophylline is a dimethylated xanthine that inhibits phosphodiesterase and blocks adenosine receptors. To relaxing effect of theophylline on smooth muscles and its effects on the urinary system, it seems it could reduce complications after inserting Double-J stent especially ureteral stent syndrome. Method: In this double-blind placebo-controlled randomized clinical trial, 67 patients were enrolled. Mean (SD) age of control and theophylline group was 51.8 (12.5) and 43.9 (10.4) years old, respectively. Patients were randomized into two groups of control and theophylline. All patients were stenting with silicon Double J. Theophylline group received 100 mg of theophylline, twice daily for 30 days, while control group received placebo. Stent symptoms were assessed by questionnaire and urine culture was performed before stent removal at removal day. Statistical analysis was performed using Chi-squared test and t test with P < 0.05 considered significant. Logistic regression models were fitted, crudely and adjusted for age and sex. Result: Of 67 eligible patients, 60 completed the study. Theophylline significantly decreased percentages of gross hematuria (P < 0.001), dysuria (P < 0.001), and urinary frequency (P < 0.001). Microscopic hematuria (P = 0.042) and chills (P = 0.042) also decreased after theophylline. Conclusion: Theophylline could be an effective and safe choice for reducing SRS among patients undergoing Double-J stent insertion. [ABSTRACT FROM AUTHOR]

Background: After colorectal surgery, acute kidney injury (AKI) results from a complex interplay of multiple independent causes and preventive measures that occur during the hospitalization. Prophylactic stenting for ureter identification has been identified as a potential cause, but the evidence is conflicting, possibly because of differing baseline characteristics and procedure-related approaches. Objective: This retrospective cohort study assesses the role of stents in the etiology of AKI after determining the independent predictors of AKI. Methods: From a population of 1224 consecutive colorectal patients (from 8/1/2016 through 12/31/2021), 382 (31.2%) received ureteral stents, and propensity score matching was used to create stented and control groups. Emergent cases and patients with sepsis were excluded from the analysis. Previously identified independent predictors of AKI, minimally invasive procedures, and a history of diabetes mellitus were used as criteria to create two balanced groups. Results: Baseline demographic characteristics and procedure-related factors baseline factors were similar between the groups. There was no difference in the rate of AKI between stented patients and controls (P = 0.82), nor was there any difference in postoperative complications, such as chronic renal insufficiency (CRI, P = 0.49), average postoperative creatinine (P = 0.67), urinary tract infections (UTI, P = 0.82), any postoperative infection (P = 0.48), in-hospital complications (P = 1.00), length of stay (LOS, P = 0.15), and 30-day readmissions (P = 0.79). Conclusions: In a population of patients where stenting was frequently employed, ureter stents placed for identification did not appear to cause AKI or AKI-related complications. [ABSTRACT FROM AUTHOR]

Abstract Ureteral obstruction is a prevalent urological condition associated with significant complications. The purpose of our study was to assess the safety and efficacy of a novel self-expanding, large caliber, biocompatible polymer-coated ureteral stent (Allium) for the treatment of ureteral obstructions. We conducted a retrospective analysis of data from patients who underwent Allium ureteral stent placement at our institute between November 2018 and May 2023. Demographic, clinical, and perioperative parameters were collected and analyzed. Logistic regression analyses were performed to identify preoperative factors predicting Allium stent migration. The study cohort comprised 30 patients who received a total of 40 successfully implanted Allium stents. No significant adverse events related to the insertion procedure were observed. During a median follow-up period of 29 months (range: 1–60 months), migration occurred in 11 (27.5%) stents while encrustation was noted in 8 (20%) stents. The median functional duration of the Allium stents was found to be 22 months (range:1–60 months), with an overall functioning rate at last follow-up being recorded as 59.5%. Multivariate analysis revealed that the glomerular filtration rate of the ipsilateral kidney was the sole risk factor predictive of Allium stent migration. With its minimal invasiveness and good tolerability, the Allium stent represents a safe and viable management option for treating ureteric obstructions; however, it should not be considered as definitive treatment but rather as an alternative option for patients unwilling or unsuitable for definitive treatment, particularly high-risk individuals or elderly patients exhibiting decreased ipsilateral glomerular filtration rates.

Background & Aims: The primary treatment for ureteric obstruction in modern urological practice is the placement of a ureteral stent. Likewise, a standard tool is needed for collecting the data to ensure the ureteral stent is removed. The purpose of this study is to identify the minimum data set (MDS) required for the ureteral stent registry at Urmia University of Medical Sciences. Materials & Methods: This research is a cross-sectional descriptive study conducted in two phases. The first phase extracted relevant data elements based on previous studies. In the second phase, a Delphi questionnaire was compiled and given to 20 urologists and experts in medical informatics and health information management using the data elements obtained from the first phase. The MDS of the system was determined during two Delphi steps. This study used descriptive statistics and SPSS software for data analysis. Results: A total of 78 data items were identified through analyzing various articles. After evaluating the results of the two stages of the Delphi questionnaire, the MDS for the ureteral stent registry was finalized with 63 data elements in 7 categories, including demographic information, social history, medical history, clinical information, diagnostic measures, treatment measures, and patient discharge. Conclusion: This study aimed to propose a MDS for the ureteral stent registry system. This data can greatly assist in effectively organizing information, supporting evidence-based decision-making, and facilitating high-quality clinical research. Furthermore, it enables the evaluation of treatment outcomes, monitoring of progress, and comparison of care standards.

PURPOSE: To evaluate the efficacy of interventional radiological (IR) procedures in iatrogenic urinary tract injury and investigate the factors affecting the outcome. METHODS: Fifty-eight patients (21 male) with a mean age of 50.3 ± 15.8 years referred for iatrogenic urinary tract injury were enrolled in this study. Technical success was defined as (i) successful placement of a nephrostomy catheter within the renal pelvis and/or (ii) successful antegrade ureteral stent placement (double J stent) between the renal pelvis and bladder lumen. Complete resolution was defined as maintained ureteral patency without an external drain and ureteral stent. The factors that may affect complete resolution [ureteral avulsion, ureterovaginal fistula (UVF), history of malignancy/radiotherapy, and time to IR management] were also investigated. The receiver operating characteristic analysis was performed to estimate the cut-off time point for the IR management timing affecting complete resolution. RESULTS: The technical success rate for nephrostomy and ureteral stent placement was 100% (n = 58/58) and 78% (n = 28/36), respectively. In 14 patients, non-dilated pelvicalyceal systems were evident. In 18 patients, no further intervention after percutaneous nephrostomy was performed due to (i) poor performance status (n = 6) and (ii) reconstruction surgery upon clinicians’ and/or patients’ request (n = 12). Reconstruction surgery was required in 11 of the remaining 40 patients due to failure of percutaneous treatment (n = 11/40, 27.5%). In six of the patients, ureteral stents could not be removed due to the development of benign ureteral strictures (n = 6/40, 15%). Our complete resolution rate was 57.5% (n = 23/40). Age, gender, type of surgery (endoscopic or open), side and location of the injury did not statistically affect the complete resolution rate. The presence of ureteral avulsion, history of malignancy and radiotherapy individually or in combination significantly affected the complete resolution rate negatively. The presence of UVF also had a negative effect on the complete resolution rate; however, it did not reach statistical significance. Delayed intervention was also a significant factor related to lower complete resolution. The optimal cut-off point of the time interval for favorable clinical outcome was found to be 0–19th day following the surgery. CONCLUSION: IR procedures are safe and effective in the management of iatrogenic urinary tract injuries. Antegrade ureteral stenting should be performed as soon as possible to establish ureteral integrity without the development of stricture.

To assess (i) clinical and pregnancy characteristics, (ii) patterns of surgical procedures, and (iii) surgical morbidity associated with cesarean hysterectomy for placenta accreta spectrum based on the specialty of the attending surgeon. The Premier Healthcare Database was queried retrospectively to study patients with placenta accreta spectrum who underwent cesarean delivery and concurrent hysterectomy from 2016 to 2020. Surgical morbidity was assessed with propensity score inverse probability of treatment weighting based on surgeon specialty for hysterectomy: general obstetrician-gynecologists, maternal-fetal medicine specialists, and gynecologic oncologists. A total of 2240 cesarean hysterectomies were studies. The most common surgeon type was general obstetrician-gynecologist (n = 1534, 68.5%), followed by gynecologic oncologist (n = 532, 23.8%) and maternal-fetal medicine specialist (n = 174, 7.8%). Patients in the gynecologic oncologist group had the highest rate of placenta increta or percreta, followed by the maternal-fetal medicine specialist and general obstetrician-gynecologist groups (43.4%, 39.6%, and 30.6%, P <.001). In a propensity score-weighted model, measured surgical morbidity was similar across the three subspecialty groups, including hemorrhage / blood transfusion (59.4–63.7%), bladder injury (18.3–24.0%), ureteral injury (2.2–4.3%), shock (8.6–10.5%), and coagulopathy (3.3–7.4%) (all, P >.05). Among the cesarean hysterectomy performed by gynecologic oncologist, hemorrhage / transfusion rates remained substantial despite additional surgical procedures: tranexamic acid / ureteral stent (60.4%), tranexamic acid / endo-arterial procedure (76.2%), ureteral stent / endo-arterial procedure (51.6%), and all three procedures (55.4%). Tranexamic acid administration with ureteral stent placement was associated with decreased bladder injury (12.8% vs 23.8–32.2%, P <.001). These data suggest that patient characteristics and surgical procedures related to cesarean hysterectomy for placenta accreta spectrum differ based on surgeon specialty. Gynecologic oncologists appear to manage more severe forms of placenta accreta spectrum. Regardless of surgeon's specialty, surgical morbidity of cesarean hysterectomy for placenta accreta spectrum is significant. • Surgical morbidity at cesarean hysterectomy for PAS was evaluated per surgeon's specialty. • Gynecologic oncologists appear to manage more severe forms of PAS. • Regardless of surgeon's specialty, surgical morbidity of cesarean hysterectomy for PAS was significant. [ABSTRACT FROM AUTHOR]

Background: During the management of patients with hydronephrosis, a possibility of retrocaval ureter (RCU) may emerge indicated by a fish-hook sign or its mimickers. Owing to infrequent incidence, the proper way to diagnose or exclude an RCU is challenging and has not been discussed previously. Methods: The aim of this study was to retrospectively evaluate the children who were suspected to have an RCU during management for urinary tract dilation. An RCU may be missed or misdiagnosed owing to rare incidence. Results: The children with urinary tract dilation in whom RCU was considered are enrolled in the study (n = 13). The demographics of the patients, findings suggesting RCU, evaluation process, management, and final diagnosis are retrospectively evaluated. The final diagnosis of the patients was RCU (n = 4), ureteropelvic junction obstruction (UPJO) (n = 7), and duplicated collecting system (n = 2). An RCU was confirmed or excluded by ultrasonography (US) while there was a stent in the ureter in 6 patients and by laparoscopic exploration in the other 7 patients. Four underwent correction for RCU, 7 for UPJO, 1 for reflux, and 1 ureterocele puncture. Conclusion: The fish-hook sign is a rare conflicting radiological finding that can be encountered in imaging studies. This uncommon finding needs confirmation or exclusion of a possible RCU as missed cases manifested after failed pyeloplasty or ureteroneocystostomy were reported. Radiological evaluation (by US or cross-sectional studies) while there is a stent in the ureter is the most satisfactory radiological technique to confirm or exclude an RCU. Alternatively, being aware of a possible RCU and performing a more extensive dissection may be necessary during surgery to confirm or exclude it. If available, laparoscopy may provide this goal in a minimally invasive manner with superior visualization. [ABSTRACT FROM AUTHOR]

PURPOSE To evaluate the efficacy of interventional radiological (IR) procedures in iatrogenic urinary tract injury and investigate the factors affecting the outcome. METHODS Fifty-eight patients (21 male) with a mean age of 50.3 ± 15.8 years referred for iatrogenic urinary tract injury were enrolled in this study. Technical success was defined as (i) successful placement of a nephrostomy catheter within the renal pelvis and/or (ii) successful antegrade ureteral stent placement (double J stent) between the renal pelvis and bladder lumen. Complete resolution was defined as maintained ureteral patency without an external drain and ureteral stent. The factors that may affect complete resolution [ureteral avulsion, ureterovaginal fistula (UVF), history of malignancy/ radiotherapy, and time to IR management] were also investigated. The receiver operating characteristic analysis was performed to estimate the cut-off time point for the IR management timing affecting complete resolution. RESULTS The technical success rate for nephrostomy and ureteral stent placement was 100% (n = 58/58) and 78% (n = 28/36), respectively. In 14 patients, non-dilated pelvicalyceal systems were evident. In 18 patients, no further intervention after percutaneous nephrostomy was performed due to (i) poor performance status (n = 6) and (ii) reconstruction surgery upon clinicians' and/or patients' request (n = 12). Reconstruction surgery was required in 11 of the remaining 40 patients due to failure of percutaneous treatment (n = 11/40, 27.5%). In six of the patients, ureteral stents could not be removed due to the development of benign ureteral strictures (n = 6/40, 15%). Our complete resolution rate was 57.5% (n = 23/40). Age, gender, type of surgery (endoscopic or open), side and location of the injury did not statistically affect the complete resolution rate. The presence of ureteral avulsion, history of malignancy and radiotherapy individually or in combination significantly affected the complete resolution rate negatively. The presence of UVF also had a negative effect on the complete resolution rate; however, it did not reach statistical significance. Delayed intervention was also a significant factor related to lower complete resolution. The optimal cut-off point of the time interval for favorable clinical outcome was found to be 0--19th day following the surgery. CONCLUSION IR procedures are safe and effective in the management of iatrogenic urinary tract injuries. Antegrade ureteral stenting should be performed as soon as possible to establish ureteral integrity without the development of stricture. [ABSTRACT FROM AUTHOR]

Malignant ureteral stricture is caused by ureteral compression by tumor invasion or tumor metastasis to the retroperitoneum, and upper urinary tract symptoms are caused by tumor factors. Imaging examination revealed hydroureter and hydronephrosis, which may lead to renal region pain and upper urinary tract infections, even renal failure. Severity of the disease could lead to the death of the patient. Patients with malignant ureteral strictures have worse prognosis and less survival time. Clinically, there are no relevant guidelines for the diagnosis and management of malignant ureteral strictures, and diversified therapy procedures exist, yet none of them are the most suitable. Most malignant ureteral stricture patients do not tolerate open surgery. With the development and continuously maturing of endoluminal techniques, the use of minimally invasive surgery has also become more mature; more therapy options are expected to have improved over time for malignant ureteral stricture patients. The use of ureteric stents is common in the treatment of benign or malignant ureteric strictures because the features of good durability facilitate urine drainage and structurally support the vascular wall. This review article will be based on advances in ureteral stents in the maintenance therapeutic of malignant ureteral strictures. [ABSTRACT FROM AUTHOR]

Objective: To determine the effect of alpha blocker drugs on reduction of Double J Stent related symptoms. Study Design: Quasi-experimental study. Place and Duration of Study: Department of Urology, The Kidney Centre, Post Graduate Training Institute, Karachi Pakistan, from May 2014 to Nov 2019. Methodology: Total 92 patients who had unilateral stent, inserted retrograde or antegrade, were studied. On 7th postoperative day double J stent related symptoms were documented on Ureteral Stent Symptom Questionnaire and alpha-blocker was started if score is >10. After 4 weeks, data was again colected to assess mean change in Ureteral Stent Symptom Questionnaire score. Results: Of 92 patients, pre-treatment mean Ureteral Stent Symptom Questionnaire score was 38.36±16.07 and post treatment was 14.87±8.62. Mean difference between pre and post Ureteral Stent Symptom Questionnaire score was found significant (p<0.05). Conclusion: Administration of Tamsulosin has a positive effect on stent related urinary symptoms and quality of life. [ABSTRACT FROM AUTHOR]

Introduction & objectives: To evaluate ureteral stent removal (SR) using a grasper‐integrated disposable flexible cystoscope (giFC—Isiris ®, Coloplast ®) after kidney transplantation (KT), with a focus on feasibility, safety, patient experience, and costs. Material and methods: All consecutive KT undergoing SR through giFC were prospectively enrolled from January 2020 to June 2023. Patient characteristics, KT and SR details, urine culture results, antimicrobial prescriptions, and the incidence of urinary tract infections (UTI) within 1 month were recorded. A micro‐cost analysis was conducted, making a comparison with the costs of SR with a reusable FC and grasper. Results: A total of 136 KT patients were enrolled, including both single and double KT, with 148 stents removed in total. The median indwelling time was 34 days [26, 47]. SR was successfully performed in all cases. The median preparation and procedure times were 4 min [3,5]. and 45 s[30, 60], respectively. The median Visual Analog Scale (VAS) score was 3 [1, 5], and 98.2% of patients expressed willingness to undergo the procedure again. Only one episode of UTI involving the graft (0.7%) was recorded. Overall, the estimated cost per SR procedure with Isiris ® and the reusable FC was 289.2€ and 151,4€, respectively. Conclusions: This prospective series evaluated the use of Isiris ® for SR in a cohort of KT patients, demonstrating feasibility and high tolerance. The UTI incidence was 0.7% within 1 month. Based on the micro‐cost analysis, estimated cost per procedure favored the reusable FC. [ABSTRACT FROM AUTHOR]

Objective: This study is conducted to investigate characteristics of patients with xanthogranulomatous pyelonephritis (XGP) who undergo nephrectomy and to identify ways to optimise outcomes for these patients. Materials and methods: 1587 patients were queried from our institutional electronic medical records. 12 patients who underwent nephrectomy with preoperative diagnoses of XGP in the operative note were identified. Associations were analysed with Kendall's τb. p < 0.05 was statistically significant. Results: All patients were hemodynamically stable on day of surgery. Two patients died on postoperative days 1 and 3 from septic shock. Both had surgery during inpatient admission rather than electively, received relatively short duration of preoperative antibiotics (8 and 10 days), and both were on hemodialysis preoperatively. There was possible association between decreased glomerular filtration rate (τb = −0.550, p = 0.032) and death postoperatively. Among patients who lived, there was no significant association between duration of antibiotic therapy after intervention and duration of postoperative hospitalisation. Conclusion: These findings could suggest a possible association between declining renal function and mortality in our case series; and performing nephrectomy electively after a longer course of antibiotics may be associated with improved outcomes compared to nephrectomy performed during hospitalisation with a shorter course of antibiotics. Level of evidence: Level 4 [ABSTRACT FROM AUTHOR]

INTRODUCTION: To evaluate the clinical characteristics as well as the postoperative course of urolithiasis patients undergoing a ureteroscopy (URS) without stent placement. MATERIALS AND METHODS: This was a prospective case cohort study utilizing data collected in the Registry for Stones of the Kidney and Ureter (ReSKU) from a single institution between October 2015 and December 2020. We identified all consecutive patients undergoing URS for stone disease and analyzed data encompassing demographics, medical history, intra and postoperative characteristics, including complications and postoperative symptoms. Univariate and multivariate logistic regression analyses were performed based on the presence or absence of an indwelling ureteral stent. RESULTS: A total of 470 patients were included for analysis, 92 patients in the stentless group (19.5%). Factors associated with stentless ureteroscopy were a lower stone burden (p < 0.001), the pre-existence of a ureteral stent (37.4% vs. 27.9% p = 0.011), absence of an access sheath (14.6% vs. 69.5% p < 0.001), and a shorter operative time (31 vs. 58 min p < 0.001). Postoperative gross hematuria and lower urinary tract symptoms (LUTS) were reported less frequently in stentless patients (p = 0.02, p = 0.01, respectively). There was no difference in postoperative complications between both groups (15.2% vs. 12.0%, p = 0.385). On multivariate analysis, the risk of postoperative complications was associated with obesity, stone burden ≥ 1 cm, and positive preoperative urine culture. There was no patient who required emergent stent placement in the stentless group. CONCLUSION: Our data show that, in well selected patients, omitting ureteral stent placement after URS can decrease postoperative gross hematuria and LUTS without increasing postoperative complications.

Introduction: Renal colic is the most common non-obstetric cause of abdominal pain during pregnancy and is associated with a higher risk of complications in these women. When invasive treatment is required, options are temporary drainage with ureteral stent (JJ) or percutaneous nephrostomy (PCN), or immediate definitive treatment with ureteroscopy (URS). Our goal was to review the safety and efficacy of these procedures in treating urolithiasis during pregnancy. Methods: Adhering to the PRISMA checklist guidelines, we searched PubMed, Embase, and Scopus databases for articles on the efficacy and complications of the three procedures in pregnant women. The quality of evidence and risk of bias were evaluated using the Critical Appraisal Skills Programme and the Institute of Health Economics tools. Results: We included 45 articles, totaling 3424 interventions in pregnant women - 2188 URS, 719 JJ, and 517 PCN. URS was the most assessed procedure, with stone-free rates comparable to the non-pregnant patients. The most frequent complications were lower urinary symptoms and infections independently of the intervention. Obstetric complications for all interventions included 167 cases of preterm labor, resulting in 24 premature births. No statistically significant differences in post-operative complications were reported between the procedures in the few comparative studies. Conclusions: Despite the absence of high-quality studies, current evidence suggests that URS, JJ, and PCN are all safe and effective during pregnancy. As most patients submitted to temporary drainage require a second procedure post-delivery, primary URS appears more efficient. Therefore, it is the preferred option unless there are indications for temporary drainage.

The placement of ureteral stents plays a crucial role in the treatment of ureteral strictures, therefore requiring high material performance standards. In addition, depending on the etiology of ureteral strictures, there are significant differences in the retention time of ureteral stents, thus requiring different degradation rates for the stents. Therefore, it is crucial to develop stent materials with high performance and controllable degradation rates. This study explores the potential of Zn-2Cu-0.5Fe-xMn alloy as a ureteral stent material, utilizing the antibacterial effect of copper ions, the strengthening effect of Fe element on Zn-based alloys, and the accelerated degradation effect of Mn element. The research found that with the increase in Mn content, the average grain size of the alloy and the size of (Fe, Mn)Zn13 phase gradually increased, leading to a decrease in hardness. The corrosion rate of the alloy increased with the increase in Mn content, attributed to changes in grain size and standard electrode potential differences between elements. Due to the antibacterial effects of Zn ions and Cu ions, the Zn-2Cu-0.5Fe-xMn alloy exhibits good anti-stone formation capabilities. Furthermore, the alloy also demonstrates acceptable cytotoxicity. Therefore, the Zn-2Cu-0.5Fe-xMn alloy is expected to become an important implant material in urological surgery.

Ureteral stenting is one of the main methods for draining the upper urinary tract. The main drawbacks associated with the use of ureteral stents include high treatment costs, stent-associated symptoms, "forgotten" ureteral stents, encrustation, and polymer recycling after stent removal. Biodegradable ureteral stents may be solution for mentioned problems, offering several advantages: (1) avoidance of stent removal, reducing invasion procedures and health costs; (2) prevention of "forgotten" stents; (3) improvement of quality of life; (4) reduction in carbon footprint. This article presents a literature review of the recent developments in biodegradable stent technology.

Objective: To assess if there is a preferable intervention between retrograde ureteral stent (RUS) and percutaneous nephrostomy (PCN) tube, in cases of upper urinary tract stone obstruction with complications requiring urgent drainage, by evaluating outcomes regarding urinary symptoms, quality of life (QoL), spontaneous stone passage, and length of hospital stays, since there is no literature stating the superiority of one modality over the other. Methods: We searched MEDLINE and other sources for relevant articles in June 2019 without any date restrictions or filters applied. The selection was done first by the title and abstract screening and then by full-text assessment for eligibility. Only randomized controlled trials or cohort studies in patients with hydronephrosis secondary to obstructive urolithiasis that presented comparative data between PCN and RUS placement concerning at least one of the defined outcome measures were included. Lastly, MEDLINE database and PubMed platform were screened again using the same terms, from June 2019 until November 2022. Results: Of 556 initial articles, seven were included in this review. Most works were considered of moderate-to-high quality. Three studies regarding QoL showed a tendency against stenting, even though only one demonstrated statistically significant negative impact on overall health state. Two works reported significantly more post-intervention urinary symptoms in stenting patients. One article found that PCN is a significant predictor of spontaneous stone passage, when adjusted for stone size and location. Findings on length of hospital stays were not consistent among articles. Conclusion: PCN appears to be the intervention better tolerated, with less impact on the patient’s perceived QoL and less post-operative urinary symptoms, in comparison with RUS. Nevertheless, further studies with larger samples and a randomized controlled design are suggested.

Abstract Background Use of ureteral stents has become an integral part of urological practice. However, it also brought with it many complications. Double J (DJ) stent knotting is a rare stent complication, and only a few cases have been reported in the literature. Although the exact cause is unknown and, in the literature, it is generally thought that knots occur due to traction. In this case report we present for the first time that spontaneous knots can occur due to ureteral peristalsis or ureteral anomalies. Case presentation Two patients (67 and 35 aged-Caucasian person) with ureteral stones who presented to the emergency department with colicky pain and had no previous history of urological surgery. We observed knot formation in the routine urinary system radiographs taken before stent removal in two patients whose ureters were observed to be narrow during endoscopic ureteral stone treatment. The stents were successfully removed using gentle traction under general anesthesia. Conclusions We discussed the cause and solution of spontaneous knot formation. We emphasized the importance of the direct urinary system radiograph taken before DJ stent removal.

Introduction: Ureteral stents have been widely used for drainage of the upper urinary tract during both emergency and elective surgical procedures since 1967. The main pathology in which these stents are used is urolithiasis.Objective: To present our experience with the surgical treatment of patients with “forgotten” encrusted ureteral stents using a combined endourological approach.Materials and methods: Patients with encrusted ureteral stents who underwent endourological procedures from 2016 to 2022 were prospectively evaluated. They were grouped based on the degree of stent encrustation according to the FECal classification. The duration of stent placement, number and types of surgical procedures, number of procedures before complete removal of the stent and concrements, surgery duration, hospital stay, complications, concrement analysis, and frequency of complete concrement removal per surgery were compared between the groups. The combined endourological procedure was performed with the patient placed in the Galdakao-modified supine Valdivia position. This position allows simultaneous antegrade and retrograde endourological access.Results: The study included 46 patients grouped according to the FECal classification. In 38 patients, stents were successfully removed in a single procedure. The mean operative time, concrement-free status, and complication rate were 90.2 ± 19.8 minutes, 78.3%, and 32.6%, respectively. Total encrustation volume was higher for grades IV and V (5.6 ± 1.8 and 7.6 ± 2 cm3) compared with all the other grades. Percutaneous nephrolithotripsy and cystolithotripsy were the most common procedures in grades IV and V. Lithotripsy was commonly used for ureteral stent encrustation, especially in the groups with grades I and III. The operative time was longer in groups IV-V compared with groups I and II because percutaneous nephrolithotripsy was more frequent in these cases. Retrograde intrarenal surgery was performed in 88% of the cases with the combined approach to check whether concrements were present in the renal calyces and pelvis. In 5 cases, a flexible ureterorenoscope was advanced antegradely through a percutaneous access to disintegrate the encrustation of the proximal part of the stent’s ureteral section. Complications occurred in 32.6% of the patients. Most complications (26%) were minor: fever, pain, or gross hematuria. One case required segmental renal artery embolization for bleeding, and antibiotic therapy associated with an attack of pyelonephritis was adjusted in 2 cases.Conclusions: The endoscopic combined approach in the Galdakao-modified supine Valdivia position is a safe and effective technique that allows removal of “forgotten” encrusted stents, in most cases, in a single procedure. The FECal classification seems to be useful for surgical planning and prognosis.

Introduction Parenchymal renal rupture due to a ureteric calculus is extremely rare and an emergency. Case presentation A 54‐year‐old man was brought to the emergency room with left back pain without trauma. Computed tomography showed left parenchymal renal rupture with an incompletely duplicated renal pelvis, ureter, and an 11‐mm ureteric calculus in the ureterovesical junction. A ureteral stent was placed, and the patient was treated conservatively as his vital signs were stable. We performed transurethral lithotripsy after resolution of the perirenal hematoma. Conclusion To best of our knowledge, this report is the first to present a case of parenchymal renal rupture due to a ureteric calculus in an incompletely duplicated renal pelvis and ureter. Ureteric calculus within an incompletely duplicated renal pelvis and ureter is at risk of parenchymal renal rupture. Therefore, the aggressive treatment of ureteric calculus could be important.

Iatrogenic ureteral injury (IUI) during colorectal surgery is a rare complication but related to a serious burden of morbidity. This comprehensive and systematic review aims to provide a critical overview of the most recent literature about IUI prevention techniques in colorectal surgery. We performed a comprehensive and systematic review of studies published from 2000 to 2022 and assessed the use of techniques for ureteral injury prevention and intraoperative localization. 26 publications were included, divided into stent-based (prophylactic/lighted ureteral stent and near-infrared fluorescent ureteral catheter [PUS/LUS/NIRFUC]) and fluorescent dye (FD) groups. Costs, the percentage and number of IUIs detected, reported limitations, complication rates and other outcome points were compared. The IUI incidence rate ranged from 0 to 1.9% (mean 0.5%) and 0 to 1.2% (mean 0.3%) in the PUS/LUS/NIRFUC and FD groups, respectively. The acute kidney injury (AKI) and urinary tact infection (UTI) incidence rate ranged from 0.4 to 32.6% and 0 to 17.3%, respectively, in the PUS/LUS/NIRFUC group and 0–15% and 0–6.3%, respectively, in the FD group. Many other complications were also compared and descriptively analyzed (length-of-stay, mortality, etc.). These techniques appear to be feasible and safe in select patients with a high risk of IUI, but the delineation of reliable guidelines for preventing IUI will require more randomized controlled trials. [ABSTRACT FROM AUTHOR]

Background: Use of ureteral stents has become an integral part of urological practice. However, it also brought with it many complications. Double J (DJ) stent knotting is a rare stent complication, and only a few cases have been reported in the literature. Although the exact cause is unknown and, in the literature, it is generally thought that knots occur due to traction. In this case report we present for the first time that spontaneous knots can occur due to ureteral peristalsis or ureteral anomalies. Case presentation: Two patients (67 and 35 aged-Caucasian person) with ureteral stones who presented to the emergency department with colicky pain and had no previous history of urological surgery. We observed knot formation in the routine urinary system radiographs taken before stent removal in two patients whose ureters were observed to be narrow during endoscopic ureteral stone treatment. The stents were successfully removed using gentle traction under general anesthesia. Conclusions: We discussed the cause and solution of spontaneous knot formation. We emphasized the importance of the direct urinary system radiograph taken before DJ stent removal. [ABSTRACT FROM AUTHOR]

Background: In urology, ureteral stents are used to treat obstructive diseases. Hematuria (54%), fever, discomfort, and lower urinary system symptoms are the predominant symptoms related to ureteral stent. Aim: This article links stent symptoms to double-j width and length, as well as patient's height, weight, and body mass index (BMI). Ureteric Stent Symptoms Questionnaire (USSQ) was used to measure ureteral stent symptoms at 1st and 4th week of stent in situ as well as the 4th week after pigtail removal. Methods: A 200-patient prospective study, where patients were allocated into four groups following ureteral stent insertion depending on the stent characteristics. Those groups were: 4.8 Fr./26 cm (Group A), 4.8 Fr./28 cm (Group B), 6 Fr/26 cm (Group C), and 6 Fr/28 cm (Group D). Results: Men comprised 53.5% of 200 patients. Participants had an average age of 49 ± 15.5 years, height of 175 ± 8.94 cm, and BMI of 23.8 ± 7.6 cm. The laboratory results were identical between groups. At the first and fourth week, groups had similar urine symptoms, pain severity, health status and occupational activities. The difference in pain location was statistically significant. Group A had 82.4% renal back pain in the first week, whereas Group B had 68.8%, Group C 31.3% and Group D 62.5 (p = 0.04). At the fourth week, 64.7% of Group A patients reported kidney front pain, compared to 100% of Group B, 93.3% of Group C, and 100% of Group D (p = 0.04). There was statistical significance in the sexual activity of the patients. 24.4% of Group C patients stopped sexual activity before stent installation, compared to 10.6%, 8.3%, and 6.4% of the other groups (p = 0.03). A moderate percentage of patients had active sexual activity at week 4 (Group A: 7.8%, Group B: 5.8%, Group C: 8.2%, Group D: 4.1%), p = 0.83. In multivariate analysis, urinary catheter group, age, weight, height, and BMI did not significantly affect urine index score (UIS), pain index score (PIS), general health (GH), quality of work (QW), and quality of sex (QS). Conclusions: Despite various attempts to establish the best ureteral stent, the effect of double-j stent physical features on stent-related symptoms remained unknown. No verdict is conceivable without adequate empirical data. [ABSTRACT FROM AUTHOR]

BACKGROUND: Ureteral stents are commonly used in urology. However, complications such as encrustation and infection on the surface of the stent, and injury to the ureteral mucosa can occur after implantation, causing discomfort for patients. OBJECTIVE: We intend to confirm the biosafety of polyvinylpyrrolidone (PVP) hydrophilic coating and its lubrication properties for surface modification of ureteral stents to reduce friction and improve patient comfort. METHODS: Based on our previous studies, we have developed a PVP hydrophilic coating for surface modification of ureteral stents. We firstly investigated the cytotoxicity, intradermal irritation, delayed type hypersensitivity, and acute systemic reactions of stent coating extracts. We further characterized the break strength, retention strength, and dynamic friction of the stent. RESULTS: The cell survival rate of all experimental groups was greater than 70%. No hypersensitivity reaction, systemic toxicity reaction, or obvious intradermal reaction were observed. The above results indicate that the test results of the modified stent meet the requirements of ISO 10993-5: 2009 (Cytotoxicity); ISO 10993-10:2021 (Sensitization and Irritation); ISO 10993-11:2017 (Acute Systemic Toxicity). After soaking in artificial urine for an extended period, there was no obvious change in its super-slip performance. CONCLUSION: Our results confirm the safety and lubrication characteristics of PVP hydrophilic coating for ureteral stent surface modification. The performance of this coating has the potential to reduce complications after stent implantation, thereby improving patient comfort, reducing medical burden, and has a good clinical application prospect. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to investigate the efficacy and safety of Allium metallic ureteral stents in treating patients with refractory ureteral strictures. Materials and methods: A total of 13 patients with refractory ureteral strictures were prospectively enrolled in the study. After ureteral balloon dilation, an Allium stent was inserted into the ureter through the stricture. Serum blood urea nitrogen and creatinine levels, kidney-ureter-bladder x-ray, and renal ultrasonography reports were evaluated preoperatively, 3 months after the procedure, and at the last outpatient visit. Treatment success was defined as improvement in both renal function and the grade of hydronephrosis. Improvement was defined as the enhancement of renal function without the resolution of hydronephrosis. Adverse events were recorded. Results: The median (interquartile range [IQR]) age of the patients was 63 (46-76) years. The median (IQR) follow-up was 15 (13.5-21) months. Treatment success and improvement were noted in 9 (69.2%) and 3 (23.1%) patients, respectively. Compared with the preoperative levels, the median (IQR) serum creatinine levels were significantly improved at 3 months after the operation (1.6 [1.25-2.85] versus 1.2 [1.05-2.05]; P = 0.02) and at the last visit (1.6 [1.25-2.85] versus 1.2 [1.05-1.8]; P = 0.02). Stent migration and encrustation were noted in 3 (23.1%) and 1 (7.7%) patients, respectively. Conclusion: Allium ureteral stents are safe and effective for patients with refractory ureteral strictures. [ABSTRACT FROM AUTHOR]

Introduction: Double-J (DJ) ureteral stents are used for multiple purposes in urology. Even though they temporize the subsequent treatment of lithiasis, they may cause different symptoms that impact quality of life (QoL). Purpose: In this randomized trial, we assessed whether the diameter of ureteral stents has an impact on catheter-associated symptoms, and their impact on QoL. Methods: A total of 194 consecutive patients undergoing DJ insertion between December 2018 and December 2022 were prospectively enrolled and divided into three categories: 4.7F (Group 1, n = 71), 6F (Group 2, n = 65), and 7F (Group 3, n = 58). Within 1 week after the DJ placement, patients completed the validated Spanish version of the Ureteral Stent Symptoms Questionnaire. Continuous variables were compared using analysis of variance and Student's t-tests. For categorical data, the chi-square test was used. Results: In the domain of "work" and "additional problems," there were significant differences. In the "Work" domain, Group 1 presented the lower symptoms. In the domain "additional problems," patients in Group 1 were prescribed fewer antibiotics owing to low urinary tract symptoms. In question U4 about urinary incontinence, patients in Groups 2 and 3 developed these symptoms more than patients in Group 1. In the "sexual activity" domain, specifically in question S3 (the patient has ever suffered any type of pain during sexual activity?), patients with 4.7F presented lower scores than patients with larger catheters. Conclusion: DJ-related symptoms affect QoL in most cases. Smaller catheters produced significantly less urinary incontinence, faster work reincorporation, fewer symptoms related to sexual activity, and fewer catheter-related symptoms than 7F catheters. In contrast, Group 3 presented fewer outpatient visits because of symptoms related to the DJ. [ABSTRACT FROM AUTHOR]

Ureteral involvement by a tumor is common, and both partial and complete obstructions can result in symptoms that are distressing and debilitating, especially in cancer patients for whom the resection of the primary tumor is not considered an option. Maintaining ureteric patency in these patients is a challenge. In addition, in cases where a patient has undergone nephroureterectomy due to primary transitional cell cancer, it becomes necessary to decompress the urinary tract to preserve the contralateral kidney from irreversible damage. This is possibly due to ureteral stenting, both retrograde and anterograde, and percutaneous nephrostomy (PCN). Since imaging plays an important role in the routine monitoring of stents, their more and more increasing use requires radiologists to be familiar with these devices, their correct position, their potential complications, and their consequences. The aim of this review is to offer a comprehensive review of the imaging features of some urinary stents and to show the complications encountered in cancer patients as a direct consequence of an invasive diagnostic or therapeutic procedure. Specifically, we focus on ureteral stents and PCN. [ABSTRACT FROM AUTHOR]

Introduction and objectives: Ureteral stents have long been utilized during colorectal resections to assist in the identification of ureters intraoperatively and mitigate risk of ureteral injury. As these procedures have shifted toward robot-assisted laparoscopic methods, lighted stents have increasingly been used. The incidence of acute kidney injury (AKI) following bilateral ureteral stent placement has been reported to be as high as 41.9%. We sought to identify our single-institution risk and determine the extent to which age, sex, and stent type affected incidence of AKI. Methods: A retrospective analysis was performed at a single community hospital of all open and robotic-assisted laparoscopic colorectal surgeries from October 2012 to April 2022. If requested, ureteral stents were placed bilaterally by a urologist and later removed by the surgeon. Non-lighted stents used were 5 Fr whistle-tip (BARD); lighted stents were 6 Fr with a fiberoptic core (STRYKER). Kidney failure was described as a rise of creatinine to ≥ 1.5 times the preoperative value, per KDIGO guidelines. Results: 633 consecutive colorectal surgeries were evaluated, with no stents placed in 237 cases, non-lighted stents placed in 137 cases, and lighted stents placed in 259 cases. No ureteral injuries were observed. Overall incidence of AKI for non-stented surgeries was 0.8% vs 5.8% for non-lighted stents and 5.8% for lighted stents. Patient age was the most significant factor in AKI incidence: for patients under 60, there was no statistical difference in AKI incidence for stented vs non-stented procedures (2.2% vs 1.1%). For patients over 60, the risk of AKI was 10.5% for stented vs 0.7% for non-stented. Female patients had statistically significant risk differences, with AKI incidence of 7.1% stented vs 0.0% non-stented. AKI completely resolved in all cases, regardless of cohort. Conclusions: In patients under age 60, the use of stents was not associated with an increased risk of AKI. For women and those over 60, stents pose a higher risk of transient AKI. Overall incidence of AKI in our larger and single-institution community hospital population was significantly lower than reported in other studies. No statistical difference was observed, overall, in AKI incidence between lighted and non-lighted stents. [ABSTRACT FROM AUTHOR]

Objectives: To determine whether urinary symptoms are significantly improved with a shorter duration of stent placement without an increase in complications. Methods: A total of 100 patients were prospectively randomized to two groups, either a 3-day (n = 59, Group 1) or 7-day (n = 41, Group 2) stent placement group depending on date of operation. Patients submitted Ureteral Stent Symptom Questionnaires both while stents were in situ and 2 to 3 days after removal. Results: Group 2 reported greater urinary symptoms (p < 0.001) and pain (p < 0.001) with stents in situ compared with Group 1. Urinary symptoms (p < 0.001), pain (p = 0.003), and general health (p = 0.02) were more severe in Group 2 after stent removal as well. The analysis also revealed that urinary symptoms, pain, and general health improved after stent removal compared with stent in situ (p < 0.001). There were no significant differences in work-related functioning between two groups. There was one complication in Group 1 requiring bilateral stent replacement. There were no significant differences in emergency department visits, unplanned clinic visits, or hospitalizations between Groups 1 and 2. Conclusions: Patients with stent removal at 3-day group had better reported urinary, pain, and general health score compared with 7-day group. Patients after stent removal had improved urinary symptoms, pain symptom, and general health compared with ureteral stent in situ. There was no statistically significant difference in complications between the groups. [ABSTRACT FROM AUTHOR]

Purpose: To compare stent-related symptoms (SRS) in patients with double J (DJ) undergoing substitution with a pigtail suture stent (PSS) after ureteroscopy (URS), through the Ureteral Stent Symptom Questionnaire (USSQ). Materials and methods: Patients with DJ undergoing URS for stone treatment were enrolled in this prospective multicenter longitudinal study. The USSQ was submitted thrice: 2 weeks after DJ, 2 weeks after PSS and 4 weeks after PSS removal (baseline). Primary endpoint: to compare Urinary Symptom Index Score and the rate of patients with pain 2 weeks after DJ and PSS. Secondary endpoints: to compare other USSQ scores and single answers 2 weeks after DJ and PSS, and DJ and PSS USSQ scores with baseline. Results: 93 patients were enrolled. 2 weeks Urinary Symptom Index Score (p < 0.001) and the percentage of patients complaining of pain (60.2% vs 88.2%, p < 0.001) were significantly in favour of PSS compared to DJ. 2 weeks scores were significantly improved with PSS compared to DJ: Pain Index (p < 0.001), VAS (p < 0.001), General Health Index (p < 0.001) and Work Performance Index (p < 0.001). All urinary symptoms were significantly decreased with PSS, including renal pain during micturition and pain interfering with life. Pain Index Score (p = 0.622) and VAS (p = 0.169) were comparable to baseline with PSS, while differed with DJ. Conclusions: Patients undergoing DJ substitution with PSS after URS report a significant decrease of SRS. Urologists may consider positioning PSS after URS in pre-stented patients to reduce the impact of SRS. [ABSTRACT FROM AUTHOR]

Background, Introduction and Aim: Ureteral stent-related symptoms (USRS) often result in unplanned phone calls and ER visits. We hypothesize that patient factors can be identified to predict these unplanned encounters. Methods and materials: Retrospective analysis of indwelling ureteral stent placements from 2014 to 2019 at a single institution by CPT code was performed. Patient demographics, discharge medications, and clinical factors were evaluated using multiple logistic regression with respect to postoperative telephone and emergency room (ER) encounters for USRS. Results: Of 374 patients, 75 (20.1%) had one or more encounters for USRS: 48 (12.8%) called the clinic and 39 (10.4%) returned to the ER. Chronic opioid use was predictive of calls to clinic and ER visits (OR 3.21 [CI 1.42–6.97], p < 0.01 and OR 3.64 [CI 1.45–8.98], p < 0.01). Survival analysis stratified by history of chronic opioid use and discharge opioid prescriptions demonstrated that opioid naïve patients receiving opioids at discharge had unplanned encounters sooner and more often [Calls p = 0.025, ER p = 0.041]), whereas patients with chronic opioid use returned to the ER sooner and more frequently when prescribed additional opioids (Calls p = 0.4, ER p = 0.002). Conclusion: Patients with a history of chronic opioid use may experience more intense USRS or have a lower threshold to seek medical care than opioid naïve patients and tend to bypass calling the clinic for the ER. Given that none of the studied medications reduced unplanned patient contact for USRS, urologists should consider upfront definitive management of urinary obstruction when appropriate. [ABSTRACT FROM AUTHOR]

We aimed to investigate the risk factors of early double-J ureteral stent (DJUS) dysfunction rates and the long-term patency of DJUSs inserted via a percutaneous approach in patients with benign uretero-ileal anastomosis stricture (UIAS) who had undergone radical cystectomy. In this retrospective study, 63 DJUS placements were placed via a percutaneous nephrostomy tract in 42 consecutive patients between May 2020 and March 2023. The technical success rate was 100% in all patients without major complications. The early dysfunction rate and long-term patency rate were 38.1% (24/63) and 84.2% (32/38), respectively. The blood clot retention grade, balloon dilatation, and length of the ureteral stricture exhibited a significant correlation with early DJUS dysfunction (blood clot retention grade: odds ratio (OR) 6.922 in grade two, p = 0.009; balloon dilatation: OR 0.186, p = 0.017; length of ureteral stricture: OR 8.715, p = 0.035 in moderate stenosis, and 7.646, p = 0.028 in severe stenosis). A multivariate Cox's proportional hazard analysis revealed that blood clot retention grade and length of ureteral stricture were independent predictors of long-term DJUS patency. Percutaneous insertion of the DJUSs was safe and effective in patients with benign UIAS. [ABSTRACT FROM AUTHOR]

To assess the effect of co-trimoxazole and N-acetylcysteine (NAC), alone and in combination, on bacterial adherence to biofilm formed on ureteral stent surfaces. This prospective randomized study was conducted on 636 patients who underwent double J ureteral stent insertion after variable urological procedures. Patients were randomized into four groups: A (n = 165), no antibiotics or mucolytics during stent indwelling; B (n = 153), oral NAC (200 mg/day for children aged < 12 years old and 600 mg/day for adults) during stent indwelling; C (n = 162), oral co-trimoxazole (2 mg TMP/kg/day) during stent indwelling; and D (n = 156), both oral NAC and co-trimoxazole during stent indwelling. Two weeks following double J stent (JJ stent) insertion, urinalysis was performed on all patients and urine culture was done for all the patients at the day of double J stent removal. The stent was removed 2 weeks postoperatively, and a stent segment sized 3–5 cm from the bladder segment of the stent was sent for culture. Positive stent cultures were found in 63.6% (105/165), 43.1% (66/153), 37% (60/162), and 19.2% (30/156) patients of groups A, B, C, and D, respectively. E. coli was the organism most commonly isolated from the stent culture in all groups. The combination of co-trimoxazole and NAC was more effective in reducing bacterial adherence on ureteral stent surfaces than either alone. [ABSTRACT FROM AUTHOR]

Background: Maintaining ureteral patency is imperative to preventing renal injury and systemic infection. Ureteral stents are small conduits connecting the kidney and the bladder. They have been widely used to treat ureteral obstructions and ureteral leaks. The most problematic and frequent stent‐associated complication is stent encrustation. This occurs when mineral crystals (e.g. calcium, oxalate, phosphorus, struvite) are deposited onto the surface and internal lumen of the stent. Encrustation can lead to the obstruction of a stent and increases risk of systemic infection. As a result, ureteral stents need to be replaced typically every 2–3 months. Purpose: In this study, we present a non‐invasive, high‐intensity focused ultrasound (HIFU)‐based technique to recanalize obstructed stents. By taking advantage of the mechanical force produced by a HIFU beam, including acoustic radiation force, acoustic streaming, and cavitation, HIFU can break up encrustations, clearing the stent of obstruction. Methods: The ureteral stents for this study were obtained from patients undergoing ureteral stent removal. Under the guidance of ultrasound imaging, the encrustation in the stents were located, and then targeted by HIFU at frequencies of 0.25 and 1 MHz. The duty cycle of HIFU was 10%, and the HIFU burst repetition rate was 1 Hz, while the HIFU amplitude was varied to find the threshold pressure that would displace encrustations. The treatment duration was limited at 2 min (or 120 shots from HIFU). The treatments were carried out in two different orientations (parallel and perpendicular) of the ureteral stent with respect to the HIFU beam. For each setting, five treatments were conducted for a maximum duration of 2 min. During the entire treatment, an ultrasound imaging system was used to monitor the movement of encrustations inside the stent. The peak negative HIFU pressures needed to move the encrustations inside the stent was recorded for quantitative analysis. Results: Our results demonstrated that at both 0.25 and 1 MHz ultrasound frequencies, obstructed stents could be recanalized. At 0.25 MHz, the needed average peak negative pressure was 0.52 MPa in parallel orientation and 0.42 MPa in perpendicular orientation. At 1 MHz, the needed average peak negative pressure was 1.10 MPa in parallel orientation and 1.15 MPa in perpendicular orientation Conclusions: This first in‐vitro study has demonstrated the feasibility of non‐invasive HIFU to recanalize ureteral stents. This technology has a potential to reduce the need for ureteral stent exchange. [ABSTRACT FROM AUTHOR]

Purpose: Ureteric stents placed after ureteroscopy typically require cystoscopy for removal. Stent extraction strings allow the option of patient self-removal. This facilitates shorter stent dwell time, and cost-savings. Concerns regarding safety and limited evidence regarding patient acceptability are speculated reasons for infrequent clinical use of extraction strings. This study investigates our recent experience using routine self-removal of stents on extraction strings to provide evidence to address these concerns. Methods: In February 2020, our hospital adopted a policy for self-removal of stents on extraction strings to be routine following ureteroscopy. This was influenced by motivation to improve service capacity for diagnostic flexible cystoscopy, hospital avoidance during the pandemic, perceived improvement for the patient experience, and cost-saving. Prospective clinical and patient-reported outcome data were collected and evaluated. Results: There were 168 patients who had stents on extraction strings. Mean stent dwell time was 5.2 ± 1.8 days. Primary ureteroscopy was performed in 40.5%, and 59.5% had procedures using an access sheath. Self-removal at home was successful for 79% of patients. Stent dislodgement rate was 3.0% (5/168) and retained stents due to string detachment occurred in 1.8% (3/168). Almost all indicated they "would remove the stent on string again" (90%, 128/142) and the majority reported stent removal as "very easy" (61%, 87/142). Cost modelling estimates a total saving of AUD $148,869 per annum for routine use of extraction strings at our hospital. Conclusion: Our experience reflects that stent extraction strings may be used routinely with acceptable low complication rates, favourable patient experiences and associated cost savings. [ABSTRACT FROM AUTHOR]

Ureteral stricture caused by holmium: YAG laser lithotripsy is one of the most challenging issues for urologists. Currently, evidence for rapamycin application in reducing ureterostenosis is not sufficient. This study aimed to assess the inhibition of ureteral stricture of rapamycin-eluting stents in vitro and in vivo. A bilayered drug-eluting ureteral stent consisted of drug blending with poly (lactic-co-glycolic acid) (PU/drug stent), which was over-layered by polycaprolactone (PCL) by ultrasonic atomizing spraying. Stent morphology was observed by scanning electron microscope. A kidney-ureter-bladder model was established to simulate the stents-releasing condition, and high-performance liquid chromatography was used to measure the drug release rate. The inhibitory proliferation was detected by CCK-8. The bladder of rats was injured through electro tome, and stents were implanted for 7, 14, and 28 days. The effects of drug-eluting stents was investigated by hematoxylin-eosin staining, immunofluorescence staining, real-time quantitative polymerase chain reaction and western blot. The bilayered stents could block the burst loss of the drug and maintained a sustained delivery period because of the 5.3 μm thickness of the PCL layer. The relative growth rates of cells plotted inhibitory effect on the proliferation of human urethral scar fibroblast cells. For in vivo results of 28 days, the bilayered stent maintained structural integrity and induced less deposition of crystals, thinner and less lamina propria connective tissues were formed, and α-SMA and TGF-β1 were downregulated. Bilayered rapamycin-eluting stent is significantly effective in alleviating fibrosis in in vitro and in vivo models. The occurrence of ureteral stricture resulting from holmium: YAG laser lithotripsy presents a significant challenge for urologists. Traditional double J stents have not been proven to offer a shorter indwelling time or improved inhibition of tissue blocking. While drug-eluting stents containing rapamycin, paclitaxel, and other substances have been extensively used in treating artery stenosis, there is insufficient evidence supporting their application in reducing ureterostenosis. Consequently, a biodegradable polymer ureteric scaffold incorporating rapamycin was fabricated in this study, employing ultrasonic atomization spraying technology to optimize the bilayers composed of 75/25 poly (lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL). The efficacy of the scaffold was subsequently confirmed through in vitro and in vivo experiments. [Display omitted] [ABSTRACT FROM AUTHOR]

Introduction: The American Urological Association guidelines state that continuing anticoagulant (AC) and antiplatelet (AP) agents during ureteroscopy (URS) is safe. Through a multi-institutional retrospective study, we sought to determine whether pre-stenting in patients on AP or AC was associated with fewer URS bleeding-related complications. Methods: A series of 8614 URS procedures performed across three institutions (April 2010 to September 2017) was electronically reviewed for AC/AP use at time of URS. Records indicating AC or AP use at time of URS were then manually reviewed to characterize intraoperative and 30-day postoperative (intraoperative bleeding, postoperative hematuria, emergency department visits, hospital readmission, unplanned reoperation, phone calls, and other minor 30-day complications). Results: A total of 293 identified URS procedures were completed on patients on AC/AP therapy—112 cases were on AC only (38 were pre-stented), 158 on AP only (51 pre-stented), and 23 on both AP and AC (8 pre-stented). Patient characteristics and comorbidities were similar between the pre-stented and non-pre-stented groups. For AC and AP subjects, pre-stenting did not decrease the composite risk of bleeding complications (10.3% pre-stent vs 12.2% non-prestent, p = 0.6). Pre-stented patients did have a significantly lower likelihood of requiring an unplanned reoperation (1.0% vs 5.6%, p = 0.04). In the subgroup of patients on AP alone, pre-stented patients had significantly fewer episodes of intraoperative bleeding (0% vs 9%, p = 0.04), unplanned reoperations (0% vs 6.5%, p = 0.02), and 30-day complications (14% vs 27%, p = 0.05). In the subgroup of patients on AC alone, there were no significant differences in outcomes based on stent status. Conclusions: In this multi-institutional study, we found that pre-stenting before URS was not associated with fewer bleeding complications. However, pre-stenting appeared to be associated with improved outcomes for those patients on AP therapy. These results suggest a need for prospective studies to clarify the role of pre-stenting for URS. [ABSTRACT FROM AUTHOR]

Purpose: To assess the safety and effectiveness of magnetic ureteric stent removal with a special magnet retriever under ultrasound guidance. Methods: A total of 60 male patients, who underwent ureteroscopy from October 2020 to March 2022, were prospectively enrolled and randomized into two groups. Group A patients underwent conventional double-J (DJ) stent insertion and subsequent stent removal via flexible cystoscopy. Group B patients underwent stent insertion using magnetic ureteric stent [Blackstar, Urotech (Achenmühle, Germany)] and stents were removed using a special magnet retriever under ultrasound guidance. Stents were left in situ for 30 days in both groups. All patients had follow-ups with a ureter stent symptoms questionnaire at 3- and 30-days post stent insertion. Visual analog scale (VAS) was assessed immediately after stent removal. Results: Stent removal time (142.5 s vs 142.5 s, group A vs group B, p < 0.0001) and VAS scores (4 vs 1, group A vs group B, p = 0.0008) were significantly lower in Group B. There were no statistically significant differences between both groups in the "urinary symptoms" (p = 0.3471) and "sexual matters" (p = 0.6126) in the USSQ domains. There was marginal statistical significance favoring Group A in the "body pain" (p = 0.0303), "general health score" (p = 0.0072), "additional problems" (p = 0.0142), and "work performance" (p < 0.0001) domains. Conclusions: Magnetic ureteric stent can be considered as a safe and efficient alternative to conventional DJ stent. This approach avoids the need for cystoscopy, saving resources while minimizing patient discomfort. [ABSTRACT FROM AUTHOR]

IntroductionMalignant peritoneal mesothelioma (MPM) is an extremely rare tumor with nonspecific clinical manifestations, making diagnosis challenging.Case presentationHerein, we report a case of MPM with occult onset presenting with bilateral hydronephrosis and renal insufficiency. A 30-year-old man was admitted to the Urology Department because of recurrent bilateral lower back pain. The etiology was unclear after a series of laboratory tests, imaging examinations, bone marrow aspiration, renal puncture biopsy, ascites examination, ureteroscopy, and so on. Finally, MPM was diagnosed by laparoscopic exploration and biopsy. Moreover, during the course of the disease, the patient's bilateral ureters were compressed, and the obstruction could not be relieved after the placement of ordinary ureteral stents. Percutaneous nephrostomy or metal ureteral stenosis was appropriate in managing malignant ureteral obstruction as it could improve renal function.ConclusionsThe onset of this case was insidious, and the diagnosis was difficult, with a poor prognosis. To date, only a handful of cases have been reported. We hope this case can provide some enlightenment for our clinical work.

Background: In urology, ureteral stents are used to treat obstructive diseases. Hematuria (54%), fever, discomfort, and lower urinary system symptoms are the predominant symptoms related to ureteral stent. Aim: This article links stent symptoms to double-j width and length, as well as patient’s height, weight, and body mass index (BMI). Ureteric Stent Symptoms Questionnaire (USSQ) was used to measure ureteral stent symptoms at 1st and 4th week of stent in situ as well as the 4th week after pigtail removal. Methods: A 200-patient prospective study, where patients were allocated into four groups following ureteral stent insertion depending on the stent characteristics. Those groups were: 4.8 Fr./26 cm (Group A), 4.8 Fr./28 cm (Group B), 6 Fr/26 cm (Group C), and 6 Fr/28 cm (Group D). Results: Men comprised 53.5% of 200 patients. Participants had an average age of 49 ± 15.5 years, height of 175 ± 8.94 cm, and BMI of 23.8 ± 7.6 cm. The laboratory results were identical between groups. At the first and fourth week, groups had similar urine symptoms, pain severity, health status and occupational activities. The difference in pain location was statistically significant. Group A had 82.4% renal back pain in the first week, whereas Group B had 68.8%, Group C 31.3% and Group D 62.5 (p = 0.04). At the fourth week, 64.7% of Group A patients reported kidney front pain, compared to 100% of Group B, 93.3% of Group C, and 100% of Group D (p = 0.04). There was statistical significance in the sexual activity of the patients. 24.4% of Group C patients stopped sexual activity before stent installation, compared to 10.6%, 8.3%, and 6.4% of the other groups (p = 0.03). A moderate percentage of patients had active sexual activity at week 4 (Group A: 7.8%, Group B: 5.8%, Group C: 8.2%, Group D: 4.1%), p = 0.83. In multivariate analysis, urinary catheter group, age, weight, height, and BMI did not significantly affect urine index score (UIS), pain index score (PIS), general health (GH), quality of work (QW), and quality of sex (QS). Conclusions: Despite various attempts to establish the best ureteral stent, the effect of double-j stent physical features on stent-related symptoms remained unknown. No verdict is conceivable without adequate empirical data.

Benoît Vogt,1 Janine Dove-Rumé2 1Department of Urology, Polyclinique de Blois, La Chaussée Saint-Victor, France; 2English Department, François-Rabelais University, Tours, FranceCorrespondence: Benoît Vogt, Department of Urology, Polyclinique de Blois, 1 Rue Robert Debré, La Chaussée Saint-Victor, 41260, France, Tel +33 254906511, Fax +33 254906566, Email message@benoitvogt.frIntroduction: Ureteral stent obstruction hinders the management of malignant diseases. Adequate stent insertion through an obstructed ureter does not necessarily guarantee renal decompression and stent-related symptoms adversely affect patient comfort. There are two major problems associated with ureteral stents: obstruction and intolerance to the stents.Case Presentation: A 45-year-old woman was treated for cervical cancer with metastatic lymph nodes and ureteral obstruction with chemotherapy, radiotherapy, immunotherapy, and bilateral retrograde stenting. After recurrent stent obstruction, stent replacement was attempted more than 18 times over two years. In addition, stent-related symptoms adversely affected patient comfort. The patient was finally fitted with Superglide 8-French reinforced ureteral stents. Their replacement every six months was viewed by the patient as a relief compared to the all too frequent replacement of the previous stents. Moreover, the customized changes in the shape of Superglide stents improved patient comfort.Discussion: Recent publications tend to indicate that large-lumen ureteral stents are most likely to remain permeable over time. Various modifications of the bladder or endo-ureteral part of double-pigtail stents have been increasingly reported, with the aim of improving their tolerance while maintaining effective drainage.Conclusion: Adaptation of the internal lumen and shape of stents to the characteristics of the tumor and patient measurements appears to be important for increasing the drainage and tolerance of ureteral stents. The top priority for future ureteral stents suitable for malignant diseases should be to integrate these characteristics based on state-of-the-art data.Keywords: malignant ureteral obstruction, ureteral stent, renal failure, stent failure, stent-related symptoms

Context: The incidence of urolithiasis is increasing year by year. Ureteral stents are a popular treatment option for this condition. Efforts to improve the material and structure of stents to increase comfort and reduce complications have led to the introduction of magnetic stents. Objective: To evaluate differences in removal efficiency and safety for magnetic and conventional stents. Evidence acquisition: This study was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Data were extracted according to the PRISMA principles. We collected and combined data from randomized controlled trials on magnetic versus conventional stents to evaluate the efficiency of their removal and the associated effects. Data synthesis was performed using RevMan 5.4.1 and heterogeneity was evaluated using I2 tests. A sensitivity analysis was also performed. Key metrics included the stent removal time, Visual Analog Scale (VAS) pain scores, and Ureteral Stent Symptom Questionnaire (USSQ) scores for various domains. Evidence synthesis: Seven studies were included in the review. We found that magnetic stents had a shorter removal time (mean difference [MD] −8.28 min, 95% confidence interval [CI] −15.6 to −0.95; p = 0.03) and their removal was associated with less pain (MD −3.01 points, 95% CI −3.83 to −2.19; p