An uncommon encounter: crossed fused renal ectopia with singular ureter: a case report.

BACKGROUND: Crossed fused renal ectopia (CFRE) is a common congenital anomaly where one kidney is positioned abnormally on the opposite side of the midline, often fused with the other kidney. However, single ureter draining crossed fused renal ectopia is a rare occurrence. CASE REPORT: Here, we report a case of crossed fused renal ectopia with a single ureter in a 46-year-old Nepali male who presented with history of lithuria. Computed tomography revealed that the left kidney was situated on the right side and fused with the right kidney. The renal pelvises of both kidneys were fused, and a single ureter, located on the right side, was draining both kidneys into the bladder. The patient was advised to have regular follow-ups. CONCLUSION: Crossed fused renal ectopia with a single ureter represents a rare renal anomaly. Asymptomatic patients can typically be managed conservatively. Regular follow-up is recommended to monitor renal function, calculus formation, infections, and malignant changes.

Radiological signs of stone impaction add no value in predicting spontaneous stone passage.

Stone size and location are key factors in predicting spontaneous stone passage (SSP), but little attention has been paid to the influence of radiological signs of stone impaction (RSSI). This research aims to determine whether RSSI, alongside stone size, can predict SSP and to evaluate the consistency of ureteral wall thickness (UWT) measurements among observers. In this retrospective study, 160 patients with a single upper or middle ureteral stone on acute non-enhanced computed tomography (NCCT) were analysed. Patient data were collected from medical records. Measurements of RSSI, including UWT, ureteral diameters, and average attenuation above and below the stone, were taken on NCCT by four independent readers blind to the outcomes. The cohort consisted of 70% males with an average age of 51 ± 15. SSP occurred in 61% of patients over 20 weeks. The median stone length was 5.7 mm (IQR: 4.5-7.3) and was significantly shorter in patients who passed their stones at short- (4.6 vs. 7.1, p < 0.001) and long-term (4.8 vs. 7.1, p < 0.001) follow-up. For stone length, the area under the receiver operating characteristic curve (AUC) for predicting SSP was 0.90 (CI 0.84-0.96) and only increased to 0.91 (CI 0.85-0.95) when adding ureteral diameters and UWT. Ureteral attenuation did not predict SSP (AUC < 0.5). Interobserver variability for UWT was moderate, with ± 2.0 mm multi-reader limits of agreement (LOA). The results suggest that RSSI do not enhance the predictive value of stone size for SSP. UWT measurements exhibit moderate reliability with significant interobserver variability.

Steady-state versus burst lasing techniques for thulium fiber laser.

OBJECTIVE: To evaluate the stone ablation rate and direct thermal damage from thulium fiber laser (TFL) lithotripsy using continuous (C) and burst (B) lasing techniques on an in vitro ureteral model. METHODS: The TFL Drive (Coloplast, Humlebaek, Denmark) was used in an in vitro saline-submerged ureteral model. Ten participants, including five junior and five experienced urologists, conducted the experimental setup with 7 different settings comparing two lasing techniques: steady-state lasing (0.5 J/10 Hz = 5W for 300 s and 0.5 J/20 Hz = 10W for 150 s) and burst, intermittent 5 s on/off lasing (0.5 J/20 Hz, 0.5 J/30 Hz, 0.5 J/60 Hz, 0.1 J/200 Hz, and 0.05 J/400 Hz) with a target cumulative energy of 1500 J using cubic 125 mm3 phantom BegoStonesTM. Ureteral damage was graded 1-3 based on the severity of burns and holes observed on the surface of the ureteral model. RESULTS: The were no significant differences in stone ablation mass neither between C and B lasing techniques, nor between expertise levels. At C lasing technique had only mild ureteral lesions with no significant differences between expertise levels (p: 0.97) or laser settings (p: 0.71). At B lasing technique, different types of thermal lesions were found with no expertise (p: 0.11) or setting (p: 0.83) differences. However, B laser setting had higher grade direct thermal lesions than C (p: 0.048). CONCLUSION: Regarding efficacy, C and B lasing techniques achieve comparable stone ablation rates. Safety-wise, B lasing mode showed higher grade of direct thermal lesions. These results should be further investigated to verify which of the lasing mode is the safest in vivo. Until then and unless proven otherwise, a C mode with low frequency should be recommended to avoid ureteral wall lesions.

Risk and protective factors for secondary procedures after endoscopic dilatation of primary obstructive megaureters.

PURPOSE: High-pressure balloon dilatation (HPBD) of the ureterovesical junction with double-J stenting is a minimally invasive alternative to ureteral reimplantation or cutaneous ureterostomy for first-line surgical treatment of primary obstructive megaureter (POM). The aim of our study was to identify the risk factors associated with the need for secondary procedures due to HPBD failure. METHODS: Prospective data were collected from patients who underwent HPBD for POM between 2007 and 2021 at a single institution. The collected data included patient demographics, diagnostic modalities, surgical details, results, and follow-up. Multivariate logistic regression analysis was performed. RESULTS: Fifty-five ureters underwent HPBD for POM in 50 children, with a median age of 6.4 months (IQR: 4.5-13.8). Nineteen patients (37.25%) underwent secondary ureteric reimplantation, with a median of 9.8 months after primary HBPD (95% CI 6.2-9.9). The median follow-up was 29.4 months (IQR: 17.4-71). Independent risk factors for redo-surgery in a multivariate logistic regression model were: progressive ureterohydronephrosis (OR = 7.8; 95% CI 0.77-78.6) and early removal of the double-J stent. A risk reduction of 7% (95% CI 2.2%-11.4%) was observed per extra-day of catheter maintenance. The optimal cut-off point is 55 days, ROC curve area: 0.77 (95% CI 0.62-0.92). Gender, distal ureteral diameter, pelvis diameter, dilatation balloon diameter and preoperative differential renal function did not affect the need for reimplantation. CONCLUSIONS: The use of a double-J stent for at least 55 days seems to avoid the need for a secondary procedure. Therefore, we recommend removing the double-J catheter at least 2 months after the HBPD.

Application of 11/13Fr suctioning ureteral access sheath and 8.55Fr single-use digital flexible ureteroscope in one-stage flexible ureteroscopic lithotripsy: an initial experience of 900 cases.

OBJECTIVES: To report our initial experience of one-stage flexible ureteroscopic lithotripsy(FURL) with 11/13Fr suctioning ureteral access sheath(UAS) and 8.55Fr single-use digital flexible ureteroscope(SDFU) in upper ureteral or renal calculi. MATERIALS AND METHODS: We retrospectively collected the clinical data of 900 adult patients with upper ureteral or renal calculi treated by FURL with 11/13Fr suctioning UAS and 8.55Fr SDFU from January 2022 to April 2024. Demographics, peri- and postoperative outcomes were assessed. RESULTS: In all, 40 of 940 cases(4.26%) failed to introduce UAS and required second-stage FURL because of ureterostenosis and were excluded. Mean stones size of the remaining 900 eligible cases was 1.68 ± 0.58 cm in greatest diameter. There were 228 cases of upper ureteral stone, 456 cases of renal stone and 216 cases of concomitant ureteral and renal calculi. The mean operation time was 52.20 ± 20.21 min and the postoperative hospital stay was 2.87 ± 1.37 days. The stone-free rate of 1 month postoperatively was 89.56% and only 2.44% of patients with residue underwent additional reoperation. The rate of postoperative fever, postoperative pain needing analgesic and slight ureteral mucosal injury were 5.11%, 8.22% and 7.78%, respectively. None of patient suffered from severe complications, such as sepsis or ureteral perforation. CONCLUSION: It's practical and suitable for the vast majority of adult patients to undergo FURL in single session with 11/13Fr suctioning UAS without preoperative stenting. FURL with 11/13Fr suctioning UAS and 8.55Fr SDFU is feasible, reliable, safe, and efficient in the management of renal stone and upper ureteral stone.

CT-Based Predictors of Spontaneous Ureteral Stone Passage.

OBJECTIVE: To assess CT-scan based parameters, particularly ureteral wall thickness (UWT), in predicting spontaneous ureteral stone passage. STUDY DESIGN: Cross-sectional, analytical study. PLACE AND DURATION OF THE STUDY: Section of Urology, Department of Surgery, The Aga Khan University Hospital, Karachi, Pakistan, from June to November 2023. METHODOLOGY: Patients with symptomatic, single, radio-opaque, unilateral ureteral stones having size ≤10 mm with normal kidney functions, diagnosed by non-contrast CT-scan KUB, and treated by conservative option for four weeks were enrolled. Clinical and radiological predictors for stone passage (SP), including stone size, area, laterality, location, density, degree of hydronephrosis, maximal UWT at the stone site, and ureteral diameter and density above and below the stone, were evaluated. Binary logistic regression analysis was employed to identify predictors of stone passage. Receiver operating characteristic (ROC) curve was used to find the optimal cut-off for UWT. RESULTS: Among 34 eligible patients, 22 (64.7%) passed their stones spontaneously. Patients who passed had smaller stone size and area and lesser UWT. Stone location, laterality, degree of hydronephrosis, stone density, ureteral wall diameter, and density above and below stones were not associated with SP. Multivariate analysis revealed maximum UWT as the independent predictor of SP, with a cut-off of 1.95 mm and an accuracy of 0.94. CONCLUSION: UWT was the single most convincing factor for the spontaneous passage of ureteral stone in this study. By applying UWT's optimal cut-off value, it might be an extremely significant tool when taking decisions in daily practice. KEY WORDS: Ureteral wall thickness, Medical expulsive therapy, Non-contrast computed tomography.

Differential effect of surgical technique on intravesical recurrence after radical nephroureterectomy in patients with upper tract urothelial cancer: a systematic review and Meta-analysis.

CONTEXT: Radical nephroureterectomy (RNU) with bladder cuff resection is the standard treatment in patients with high-risk upper tract urothelial cancer (UTUC). However, it is unclear which specific surgical technique may lead to improve oncological outcomes in term of intravesical recurrence (IVR) in patients with UTUC. OBJECTIVE: To evaluate the efficacy of surgical techniques and approaches of RNU in reducing IVR in UTUC patients. EVIDENCE ACQUISITION: Three databases were queried in January 2024 for studies analyzing UTUC patients who underwent RNU. The primary outcome of interest was the rate of IVR among various types of surgical techniques and approaches of RNU. EVIDENCE SYNTHESIS: Thirty-one studies, comprising 1 randomized controlled trial and 1 prospective study, were included for a systematic review and meta-analysis. The rate of IVR was significantly lower in RNU patients who had an early ligation (EL) of the ureter compared to those who did not (HR: 0.64, 95% CI: 0.44-0.94, p = 0.02). Laparoscopic RNU significantly increased the IVR compared to open RNU (HR: 1.28, 95% CI: 1.06-1.54, p < 0.001). Intravesical bladder cuff removal significantly reduced the IVR compared to both extravesical and transurethral bladder cuff removal (HR: 0.65, 95% CI: 0.51-0.83, p = 0.02 and HR: 1.64, 95% CI: 1.15-2.34, p = 0.006, respectively). CONCLUSIONS: EL of the affected upper tract system, ureteral management, open RNU, and intravesical bladder cuff removal seem to yield the lowest IVR rate in patients with UTUC. Well-designed prospective studies are needed to conclusively elucidate the optimal surgical technique in the setting of single post-operative intravesical chemotherapy.

Cord structure within an inguinal hernia: could the ureter be involved?

Inguinal hernias are commonly encountered and are primarily managed by surgeons; however, it is unusual for retroperitoneal structures, such as the ureter, to herniate into it. More importantly, hernias containing ureters are not usually identified preoperatively unless specific imaging was ordered prior, as they are generally asymptomatic. This poses a risk to the patient as unidentified structures can be mistakenly injured during the surgery. We describe a case of a man in his 60s, who presented with a large left-sided indirect inguinoscrotal hernia. Intraoperatively, a large amount of irreducible retroperitoneal fat was encountered in addition to a cord-like structure, which was discovered to be the left ureter after reviewing imaging intraoperatively. Initially, the hernia repair was done robotically, but it was converted to open repair due to its irreducibility and the potential risk imposed on the ureter. Additionally, we discuss the aetiology and common presentations of this kind of hernia.

Advancements in Surgical Management of Megaureters.

PURPOSE OF REVIEW: To review and describe the recent evolution of surgery for the various types of pediatric megaureter. RECENT FINDINGS: Megaureter management first relies on determining the underlying cause, whether by obstruction, reflux, or a combination, and then setting appropriate surgical indications because many cases do not require surgery as shown by observation studies. Endoscopic balloon dilation has been on the rise as a major treatment option for obstructive megaureter, while refluxing megaureters can also be treated by laparoscopic and robotic techniques, whether extravesically or transvesicoscopically. During ureteral reimplantation, tapering is sometimes necessary to address the enlarged ureter, but there are also considerations for not tapering or for tapering alternatives. Endoscopic and minimally invasive surgeries for megaureter have been the predominant focus of recent megaureter literature. These techniques still need collaborative prospective studies to better define which surgeries are best for patients needing megaureter interventions.

A surprise during hernia surgery: inguinoscrotal megaureter.

BACKGROUND: Ureteroinguinal herniation is a rare occurrence that is typically diagnosed during the surgical repair of inguinal hernias. CASE PRESENTATION: We present the case of a 4-year-old male who underwent inguinal hernia repair, during which a megaureter was discovered within the hernia sac. The surgical intervention included high ligation of the hernial sac and repositioning of the ureter back into the retroperitoneum. Postoperative investigations confirmed a diagnosis of primary non-refluxing and nonobstructive megaureter. CONCLUSION: Although ureteral herniation is rare in infants, it is crucial to remain vigilant about the possibility of encountering the ureter during hernia repair to prevent potential ureteral injuries. Additionally, any associated urinary tract anomalies should be thoroughly investigated and ruled out.

Complete ureteropelvic-junction disruption following renal trauma: conservative management. / Avulsión completa de la unión pieloureteral tras traumatismo renal: manejo conservador.

INTRODUCTION: Surgical exploration in complete ureteropelvic-junction disruption (CUPJD) is still recommended by many authors. Conservative approach to pediatric renal trauma (RT) includes minimally invasive techniques such as nephrostomy, angioembolization or double-J stent placement. CASE REPORT: A 14-year-old patient with CUPJD was treated conservatively. CT-scan revealed active bleeding of the renal artery and significant urine extravasation. Coil angioembolization and nephrostomy placement were performed. An attempt to place a double-J stent was unsuccessful and surgical reconstruction was scheduled. Before surgery, methylene-blue was injected through the nephrostomy observing blue urine output through urethra. Antegrade pyelogram revealed drainage from the urinoma to the ureter. A new attempt to place an internal-external double-J-stent was successful. After 5 weeks, it was removed with total restoration of the urinary tract. CONCLUSION: Complete urinary tract restoration in some cases of CUPJD following RT is possible through a nonoperative approach. It can be safe and effective, reducing the risk of complications associated with complex surgeries.

INTRODUCCION: Muchos autores siguen recomendando la exploración quirúrgica en casos de avulsión completa de la unión pieloureteral (ACUPU). El abordaje conservador del traumatismo renal (TR) pediátrico incluye técnicas mínimamente invasivas como la nefrostomía, la angioembolización o el catéter doble J. CASO CLINICO: Paciente de 14 años con ACUPU tratada de forma conservadora. El escáner reveló la presencia de una hemorragia activa en la arteria renal, además de una importante extravasación urinaria. Se practicó angioembolización con bobinas y nefrostomía. Se intentó colocar un catéter doble J, sin éxito, por lo que se programó reconstrucción quirúrgica. Antes de la cirugía, se inyectó azul de metileno a través de la nefrostomía, observándose salida de orina azul a través de la uretra. La realización de una pielografía anterógrada reveló la presencia de drenaje desde el urinoma hacia el uréter. El segundo intento de colocar un catéter doble J interno-externo sí resultó fructífero, retirándose al cabo de 5 semanas, con restauración total del tracto urinario. CONCLUSION: La restauración completa del tracto urinario en algunos casos de ACUPU tras TR es factible sin necesidad de recurrir al abordaje quirúrgico. Se trata de un proceso seguro y eficaz que disminuye el riesgo de las complicaciones propias de las cirugías complejas.

Levopositioned caudal vena cava and circumcaval left ureter with subsequent hydronephrosis and hydroureter in a dog.

The presentation and investigation of a levopositioned caudal vena cava, a rare congenital vascular abnormality seen mainly in Bernese Mountain Dogs, which resulted in ureteral compression, hydronephrosis and hydroureter. Surgical transection, transposition and anastomosis were performed to reposition the circumcaval ureter. A 19-month-old male neutered Bernese Mountain Dog was presented with a 13-month history of vague signs including intermittent abdominal pain, inappetence and diarrhoea, which were poorly responsive to medical management. Abdominal ultrasound revealed left-sided hydronephrosis and hydroureter. Further investigation included abdominal computed tomography and pre- and post-intravenous iodinated contrast, which revealed a levopositioned caudal vena cava with associated ureteral displacement to a circumcaval position, resulting in ureteral compression and proximal dilation affecting both the proximal ureter and the left kidney. The patient was also found to have concomitant gall bladder agenesis. Surgery was performed to transect, transpose and anastomose the ureter in a normal anatomical position, and the patient made an excellent clinical recovery. All gastrointestinal signs resolved within 2 weeks of surgery and remained resolved 12 months later. Follow-up ultrasound and pyelography were performed at 4-month post-surgery, revealing a mild improvement in the hydronephrosis and hydroureter. Although rare, circumcaval ureter should be considered a differential in dogs presenting with hydroureter and hydronephrosis, especially Bernese Mountain Dogs.

The impact of siphoning effect on renal pelvis pressure during ureteroscopy using an in vitro kidney and ureter model.

PURPOSE: To experimentally measure renal pelvis pressure (PRP) in an ureteroscopic model when applying a simple hydrodynamic principle, the siphoning effect. METHODS: A 9.5Fr disposable ureteroscope was inserted into a silicone kidney-ureter model with its tip positioned at the renal pelvis. Irrigation was delivered through the ureteroscope at 100 cm above the renal pelvis. A Y-shaped adapter was fitted onto the model's renal pelvis port, accommodating a pressure sensor and a 4 Fr ureteral access catheter (UAC) through each limb. The drainage flowrate through the UAC tip was measured for 60 s each run. The distal tip of the UAC was placed at various heights below or above the center of the renal pelvis to create a siphoning effect. All trials were performed in triplicate for two lengths of 4Fr UACs: 100 cm and 70 cm (modified from 100 cm). RESULTS: PRP was linearly dependent on the height difference from the center of the renal pelvis to the UAC tip for both tested UAC lengths. In our experimental setting, PRP can be reduced by 10 cmH20 simply by lowering the distal tip of a 4 Fr 70 cm UAC positioned alongside the ureteroscope by 19.7 cm. When using a 4 Fr 100 cm UAC, PRP can drop 10 cmH20 by lowering the distal tip of the UAC 23.3 cm below the level of the renal pelvis. CONCLUSION: Implementing the siphoning effect for managing PRP during ureteroscopy could potentially enhance safety and effectiveness.

Robotic-assisted laparoscopic resection of a pelvic solitary fibrous tumour causing distal ureteric compression.

This case report describes a male in his late 40s with a 4 cm pelvic mass compressing the left distal ureter, resulting in left hydroureteronephrosis. Biopsy of the mass was suggestive of a solitary fibrous tumour. The patient underwent a robotic-assisted laparoscopic excision of the left pelvic mass. Intraoperatively, the mass was found to be densely adhered to the ureter, necessitating a left distal ureterectomy and ureteric reimplantation. Subsequent histopathological analysis revealed the mass was a solitary fibrous tumour with no evidence of malignancy.

Kidney, ureter, and urinary bladder segmentation based on non-contrast enhanced computed tomography images using modified U-Net.

This study was performed to segment the urinary system as the basis for diagnosing urinary system diseases on non-contrast computed tomography (CT). This study was conducted with images obtained between January 2016 and December 2020. During the study period, non-contrast abdominopelvic CT scans of patients and diagnosed and treated with urinary stones at the emergency departments of two institutions were collected. Region of interest extraction was first performed, and urinary system segmentation was performed using a modified U-Net. Thereafter, fivefold cross-validation was performed to evaluate the robustness of the model performance. In fivefold cross-validation results of the segmentation of the urinary system, the average dice coefficient was 0.8673, and the dice coefficients for each class (kidney, ureter, and urinary bladder) were 0.9651, 0.7172, and 0.9196, respectively. In the test dataset, the average dice coefficient of best performing model in fivefold cross validation for whole urinary system was 0.8623, and the dice coefficients for each class (kidney, ureter, and urinary bladder) were 0.9613, 0.7225, and 0.9032, respectively. The segmentation of the urinary system using the modified U-Net proposed in this study could be the basis for the detection of kidney, ureter, and urinary bladder lesions, such as stones and tumours, through machine learning.

Effect of perioperative tamsulosin on successful ureteral access sheath placement and stent-related symptom relief: A double-blinded, randomized, placebo-controlled study.

PURPOSE: This study investigated the effect of administering tamsulosin before surgery on the successful insertion of a 12/14 French (F) ureteral access sheath (UAS) during the procedure, as well as the impact of preoperative and postoperative tamsulosin use on symptoms related to the ureteral stent. MATERIALS AND METHODS: This study was a randomized, single-center, double-blinded, placebo-controlled trial involving 200 patients who underwent unilateral retrograde intrarenal surgery. Patients received either tamsulosin (0.4 mg) or placebo 1 week before surgery until stent removal. Patients were randomly assigned to one of four groups. Group 1 received tamsulosin throughout the study period. Group 2 received tamsulosin before surgery and placebo after surgery. Group 3 received placebo before surgery and tamsulosin after surgery. Group 4 received placebo before and after surgery. The USSQ (Ureteral Stent Symptom Questionnaire) was completed between postoperative days 7 and 14 immediately before stent removal. RESULTS: A total of 160 patients were included in this analysis. Their mean age was 55.0±11.0 years, and 48 patients (30.0%) were female. In the group that received preoperative tamsulosin, the success rate of 12/14F UAS deployment was significantly higher than that of the preoperative placebo group (88.0 vs. 75.3%, p=0.038). Preoperative and postoperative tamsulosin did not significantly alleviate symptoms related to the ureteral stent. CONCLUSIONS: Our results revealed that preoperative administration of tamsulosin improved the success of larger-sized UAS, whereas preoperative and postoperative tamsulosin use did not significantly alleviate symptoms related to ureteral stents.

Donor Kidney With Complete Duplication of Ureter: Is It Safe for Transplantation?

Renal transplantation is the best modality of treatment for patients with end-stage renal disease. Donor shortage remains a substantial problem, for which different strategies are employed, including acceptance of marginal donors and donor kidneys with anatomic variations. We performed a successful kidney transplant of a donor kidney that had complete duplication of the ureter. After transplant, the recipient had no urinary complications.

Novel anti-reflux ureteral skirt: proof of concept in a Yorkshire-Landrace pig model.

INTRODUCTION: Stents with anti-reflux properties have been previously described in various studies but not widely adopted. We designed, constructed and tested a novel umbrella-looking anti-reflux skirt on a double J stent at the level of the ureteral orifice in a previous ex-vivo study. This study serves as a proof of concept of testing this prototype in a porcine model. METHODS: 3 Yorkshire-Landrace pigs were put under general anaesthesia. Conventional bilateral retrograde stenting with white-colored double-J stents were performed. Deployment of anti-reflux skirt was performed unilaterally. Capsaicin mixed with methylene blue and saline were instilled in the bladder. Both stents were removed and methylene blue stain were inspected to assess the level of reflux. Bilateral stenting was performed again and stents/skirt prototype were left in-situ for 1 week. The procedure was repeated on Day 7 to re-test the anti-reflux property of the prototype after ureteral dilatation. RESULTS: Intraluminal reflux was evident, with methylene blue stain seen on the inner surface of the stents. Extraluminal reflux was proved with blue stain seen on the outer surface of the stents, both in undilated and dilated ureters. Study also proved the anti-reflux property of the skirt as the blue stain didn't go beyond the skirt, whereas the contralateral stent was stained up to proximal ureter. CONCLUSION: In this porcine in-vivo study, we elucidated that reflux occurred were both intraluminal and extraluminally. As a proof of concept, it also showed the anti-reflux property of a novel ureteral skirt.