Adult iatrogenic ureteral injury and strictureeincidence and treatment strategies

Iatrogenic ureteral injuries and strictures are relatively common complication of pelvic surgery and radiation treatment.Left untreated they are associated with severe shortand long-term complications such as urinoma,septic state,renal failure,and loss of a renal unit.Treatment depends on timing of diagnosis,as well as extent of injury,and ranges from simple endoscopic management to complex surgical reconstruction under usage of pedicled grafts.While recent advances in ureteral tissue engineering are promising the topic is still underreported.Historically a domain of open surgery,laparoscopic and robotic-assisted approaches have proven their feasibility in small case series,and are increasingly being utilized as means of reconstructive surgery.This review aims to give an outline of incidence and treatment of ureteral injuries and strictures in light of the latest advances.

Prevention strategies for ureteral stricture following ureteroscopic lithotripsy

Ureteral stricture formation after ureteroscopic lithotripsy is a late complication that can lead to hydronephrosis and a subsequent risk of renal deterioration.The specific incidence is unknown,and the mechanism of stricture formation has not been completely explained.In this review,we summarize the current evidence regarding the incidence of this condition and discuss its pathogenesis.We then list preventive strategies to reduce the morbidity of ureteral strictures。

Long-Term Management of Post-Transplant Ureteral Stricture with Surgical Reconstruction: A Case Series and Literature Review

Introduction: Ureteral stricture is the most common complication after kidney transplant and is largely responsible for graft dysfunction. Surgical intervention is the definitive treatment if conservative management with stenting and percutaneous nephrostomy tube placement fails and has been shown to have comparable long-term survival rates and limited post-operative complications. Methods: This is a single-center retrospective study following seven patients who received a kidney or a kidney and pancreas transplant between August 2012 and January 2021. These patients underwent surgical ureteral reconstruction after failed conservative management of a ureteral stricture. The reconstruction procedures performed were native ureter to transplanted kidney ureteropyelostomy, native bladder to transplanted renal pelvis vesicopyelostomy, non-transecting side-to-side ureteroneocystostomy, and a Boari flap creation. Data collected from electronic medical records included recipient age, gender, delayed post-transplant complications, ureteral reconstruction technique, and post-reconstruction outcomes. Renal ultrasound (RUS), renogram, nephrostogram, serum creatinine (Cr), and graft biopsy were used to assess for severity of hydronephrosis, ureteral stricture, and graft dysfunction. Serum Cr and RUS were used to assess renal function after the ureteral reconstruction. Results: Six out of seven cases resulted in reduced or resolved hydronephrosis and preserved graft function without future nephrostomy or ureteral stenting. One case required immediate revision due to persistent obstruction, and this patient had concomitant rejection leading to intrarenal stricture requiring ureterocalycostomy. Conclusions: Formal ureteral reconstruction is the definitive treatment for many cases of ureteral strictures after transplant. The surgical technique chosen for these procedures must consider the physical and functional state of the bladder, ureter, and kidney. Our series outlines multiple surgical approaches that should be considered early in the management of post-transplant ureteral strictures to limit graft dysfunction.

Prospective observational study on the prognosis of ureteral lesions caused by impacted stones via dual-energy spectral computed tomography

Objective Ureteral lesions caused by impacted ureteral stones are likely to result in postoperative ureteral stricture.On this basis,the study aimed to investigate if dual-energy spectral computed tomography can predict ureteral hardening caused by impacted stones and to explore the relationship between different types of ureteral lesions and the risk of ureteral stricture.Methods This prospective study collected data of 93 patients with impacted stones from hospital automation system during January 2018 to October 2019.They underwent an abdominal scan on a dual-energy spectral computed tomography.During surgery,the operator used ureteroscopy to identify ureteral lesions,which were classified into four categories:edema,polyps,pallor,and hardening.Seven months later,90 patients were reviewed for the degree of hydronephrosis.Results Endoscopic observations revealed 38(41%)cases of ureteral edema,20(22%)cases of polyps,13(14%)cases of pallor,and 22(24%)cases of hardening.There were significant differences in hydronephrosis,the period of impaction,the calcium concentration of the ureter,and the slope of the spectral Hounsfield unit curve between the four groups.After that,we evaluated the factors associated with ureteral hardening and found that the calcium concentration of the ureter and hydronephrosis remained independent predictors of ureteral hardening.Receiver operating characteristic curve analysis showed that 5.3 mg/cm^(3)calcium concentration of the ureter is an optimal cut-off value to predict ureteral hardening.The result of follow-up showed that 80 patients had complete remission of hydronephrosis,with a complete remission rate of 61.9%(13/21)in the hardening group and 97.1%(67/69)in the non-hardening group(p<0.001).Conclusion Calcium concentration of the ureter is an independent predictor of ureteral hardening.Patients with ureteral hardening have more severe hydronephrosis after ureteroscopic lithotripsy.When the calcium concentration of the ureter is less than 5.3 mg/cm^(3),ureteral lesions should be actively treated.

Diagnosis and management of ureteral complications following renal transplantation

When compared with maintenance dialysis,renal transplantation affords patients with end-stage renal disease better long-term survival and a better quality of life.Approximately 9% of patients will develop a major urologic complication following kidney transplantation.Ureteral complications are most common and include obstruction(intrinsic and extrinsic),urine leak and vesicoureteral reflux.Ureterovesical anastomotic strictures result from technical error or ureteral ischemia.Balloon dilation or endoureterotomy may be considered for short,low-grade strictures,but open reconstruction is associated with higher success rates.Urine leak usually occurs in the early postoperative period.Nearly 60% of patients can be successfully managed with a pelvic drain and urinary decompression(nephrostomy tube,ureteral stent,and indwelling bladder catheter).Proximal,large-volume,or leaks that persist despite urinary diversion,require open repair.Vesicoureteral reflux is common following transplantation.Patients with recurrent pyelonephritis despite antimicrobial prophylaxis require surgical treatment.Deflux injection may be considered in recipients with low-grade disease.Grade IV and V reflux are best managed with open reconstruction.

Treatment of benign ureteral stricture by double J stents using high-pressure balloon angioplasty

Background Balloon dilatation angioplasty is a minimally invasive surgery for treating benign ureteral stricture. The aim of this study was to investigate the effect of placing double J （D-J） stents using high-pressure balloon angioplasty in treating benign ureteral stricture.Methods A total of 42 patients （48 cases） with benign ureteral stricture （42 had benign ureteral stricture） were investigated by inserting dual D-J stents using high-pressure balloon angioplasty. The control group contained 50 patients （57 cases） employing the conventional balloon angioplasty with a single D-J stent inserted for comparison.Results The overall effective rate of the treated and control groups was 87.8% （36/41） and 62.7% （32/51）, respectively （P 〈0.05）.Conclusion This new approach produces a better curative effect than the conventional balloon angioplasty with a single D-J stent insertion in treating benign ureteral stricture.

A Novel Surgical Option for Urinary Tract Reconstruction in Third Renal Transplantation

Renal transplantation is generally accepted to be the best treatment for patients with end-stage renal disease, which is associated with better quality of life and better life expectancy compared with dialysis. Although the allograft survival following renal transplantation continues to improve, the absolute number of patients suffering from allograft loss continues to grow due to the increasing number of surviving renal transplant recipients.