Review of appendiceal onlay flap in the management of complex ureteric strictures in six patients

Analysis of the Therapeutic Efficacy of Laparoscopic Treatment for Fibroepithelial Polyps of the Ureter in Children

Objective: The aim of this study is to assess the efficacy and safety of laparoscopic surgery in the treatment of pediatric ureteral fibroepithelial polyp (FEP) patients. Our hypothesis is that laparoscopic surgery can effectively treat FEPs while minimizing patient discomfort and complications. Our research aims to evaluate the clinical outcomes of the surgery, including postoperative symptom relief, improvement in kidney function, and risk of postoperative complications. Methods: The clinical records of 34 patients who underwent ureteral polyp surgery at the Department of Urology at Anhui Provincial Children's Hospital between May 2014 and February 2023 were retrospectively analyzed. All patients underwent laparoscopic surgery. Among the 34 pediatric patients, there were 31 males and 3 females, with 2 on the right side and 32 on the left side. Of these cases, 24 polyps were located at the ureteropelvic junction, while seven were found in the upper segment of the ureter and three in its middle segment. Patients' ages ranged from 4 years and 3 months to 15 years, with a median age of 8 years and 6 months. All children presented with varying degrees of hydronephrosis, and preoperative clinical symptoms included ipsilateral flank or abdominal pain, hematuria, and other discomfort. Preoperative examinations mainly comprised ultrasound, intravenous pyelography, CT, or magnetic resonance urography imaging studies, as well as diuretic renography. All pediatric patients underwent laparoscopic excision of the polyp segment of the ureter, followed by renal pelvis ureteroplasty or ureter-to-ureter anastomosis. Results: All patients underwent surgery without conversion to open surgery. The surgical duration ranged from 72 to 313 minutes, with an average of 179.5 minutes. The average intraoperative blood loss was 14 mL. Postoperatively, one patient experienced leakage at the anastomotic site; however, no other significant complications occurred during or after the procedure. Postoperative histopathology confirmed the presence of FEPs in the ureter for all cases. All patients experienced a favorable postoperative recovery, with hospitalization periods ranging from 3 to 16 days and an average stay of 8.6 days. A Double-J stent was inserted in all patients for a duration of 1 to 2 months after surgery, and upon removal, follow-up color Doppler ultrasound revealed reduced hydronephrosis within 1 to 3 months. Follow-up examinations were conducted at intervals ranging from 3 to 108 months postsurgery, with an average follow-up time of 42.2 months, during which no recurrence of ureteral polyps or symptoms such as pain and hematuria was observed. Conclusions: The findings of this study demonstrate that laparoscopic excision of the polyp segment of the ureter, renal pelvis ureteroplasty, and ureter-to-ureter anastomosis represent safe and effective treatment modalities for pediatric FEPs in the ureters. This technique offers several advantages, including minimal invasiveness, rapid recovery, and definitive therapeutic efficacy, which effectively alleviate clinical symptoms and improve hydronephrosis.

Ileal ureteral replacement for the management of ureteral avulsion during ureteroscopic lithotripsy: a case series

INTRODUCTION

To describe our initial experience with ileal ureteral replacement (IUR) for the management of ureteral avulsion (UA) during ureteroscopic lithotripsy.

METHODS

Between September 2010 and April 2021, ten patients received ileal ureteral replacement for ureteral avulsion during ureteroscopic lithotripsy. Anterograde urography and computed tomography urography (CTU) were applied to evaluate the lesion. Follow-up was performed with magnetic resonance urography and renal ultrasound as well as clinical assessment of symptoms. We retrospectively analysed the clinical data of ten patients treated with ileal ureteral replacement for the treatment of ureteral avulsion.

RESULTS

Four patients underwent open ileal ureteral replacement, two underwent laparoscopic ileal ureteral replacement, and four underwent robotic-assisted ileal ureteral replacement. The mean operative time (OT) was 310 min (range 191-530). The mean estimated blood loss (EBL) was 193 mL (range 10-1000). The mean length of the ileal graft was 21 cm (range 12-25). The median postoperative hospital time was 13 days (range 7-19). All surgeries were effectively completed, and no case required open conversion in laparoscopic and robotic-assisted surgeries. There was no obvious hydronephrosis according to contrast-enhanced computed tomography 3-dimensional reconstruction images without serious complications or progressive hydronephrosis during a median follow-up duration of 51 months (range 5-131), and the success rate was 100%.

CONCLUSIONS

Our initial results and experience showed that ileal ureteral replacement for the management of ureteral avulsion during ureteroscopic lithotripsy is safe and feasible.

Bioengineering solutions for Ureteric disorders: Clinical need, challenges and opportunities

Objectives

To summarise the causes of ureteric damage and the current standard of care, discussing the risks and benefits of available therapeutic options. We then focus on the current and future solutions that can be provided by ureteric bioengineering and provide a description of the ideal characteristics of a bioengineered product.

Methods

We performed a literature search in February 2021 in: Google Scholar, Medline, and Web of Science. Three searches were conducted, investigating: (a) the epidemiology of ureteric pathology, (b) the current standard of care, and (c) the state of the art in ureteric bioengineering.

Results

The most‐common causes of ureteric damage are iatrogenic injury and external trauma. Current approaches to treatment include stent placement or surgical reconstruction. Reconstruction can be done using either urological tissue or segments of the gastrointestinal tract. Limitations include scarring, strictures, and infections. Several bioengineered alternatives have been explored in animal studies, with variations in the choice of scaffold material, cellular seeding populations, and pre‐implantation processing. Natural grafts and hybrid material appear to be associated with superior outcomes. Furthermore, seeding of the scaffold material with stem cells or differentiated urothelial cells allows for better function compared to acellular scaffolds. Some studies have attempted to pre‐implant the graft in the omentum prior to reconstruction, but this has yet to prove any definitive benefits.

Conclusion

There is an unmet clinical need for safer and more effective treatment for ureteric injuries. Urological bioengineering is a promising solution in preclinical studies. However, substantial scientific, logistic, and economic challenges must be addressed to harness its transformative potential in improving outcomes.

Should ureteroscopy be performed for patients after ureteral reconstruction with autologous onlay flap/graft?

Background

To analyze the safety and clinical significance of performing ureteroscopy after ureteral reconstruction with autologous onlay/graft. To describe the ureteroscopic appearances of the appendiceal onlay flap and lingual mucosa graft.

Methods

Beginning in August 2018, we conducted a prospective cohort study of autologous onlay/graft techniques to repair ureteral strictures. The perioperative data of 42 patients who had undergone surgery more than 6 months prior were collected prospectively. During the postoperative follow-up, ureteroscopy was performed in 27 patients (64.3%) after surgery (group A), and ureteroscopy was not performed in the other 15 patients (35.7%) (group B). We carried out a comparative study of these two groups of patients. Analyses were conducted mainly on complications related to ureteroscopy and the success rate of ureteral reconstruction surgery.

Results

There were no significant differences in patient demographic data or the length of ureteral reconstruction between the two groups (P>0.05). For the ureteroscopy group, the median time from repair surgery to ureteroscopy was 3 (range, 2-7) months, there was no poor healing of the anastomosis, and the ureteral lumen of all patients was unobstructed. Some expected observations can be found in the ureteral lumen, such as mucosa edema, stones, follicles and granulation tissue. Among the 27 patients, one patient (3.7%) developed bleeding intraoperatively and 7 patients (25.9%) were found to have low-grade (Clavien-Dindo I and II) postoperative complications, including 5 cases of fever and 2 cases of bleeding. The mean follow-up times of patients in group A and group B were 16.7±6.4 and 19.0±10.1 months, respectively. The objective success (imaging showed hydronephrosis ease) rate of the two groups was 100%. The subjective success (symptom relief) rates of group A and group B were 96.3% and 100%, respectively.

Conclusions

Patients after autologous onlay flap/graft ureteroplasty do not need to undergo routine ureteroscopy unless there is aggravation of hydronephrosis or other indications for ureteroscopy, such as stones.

The Urologist and the Appendix: A Review of Appendiceal Use in Genitourinary Reconstructive Surgery

Recently, genitourinary reconstruction has experienced a renaissance. Over the past several years, there has been an expansion of the literature regarding the use of buccal mucosa for the repair of complex ureteral strictures and other pathologies. The appendix has been an available graft utilized for the repair of ureteral stricture disease and has been infrequently reported since the early 1900s. This review serves to highlight the use of the appendix for reconstruction in urology, particularly focusing on the anatomy and physiology of the appendix, historical use, and current applications, particularly in robotic upper tract reconstruction.

Ureteral reconstruction for complex strictures: a review of the current literature

PURPOSE

Frequently employed procedures for ureteral reconstruction include balloon dilation, pyeloplasty and ureteral re-implants. However, these procedures do not work for complex ureteral disease. The goal of this literature review is to report on techniques and success rates for the following techniques: buccal graft ureteroplasty, appendiceal interposition, transureteroureterostomy, ileal ureter and autotransplantation.

METHODS

A comprehensive literature search for English-language original and review articles was conducted using PubMed. The following terms were queried: "ureteral reconstruction", "buccal graft", "appendiceal interposition", "ileal ureter", "transureteroureterostomy", "autotransplantation".

RESULTS

Procedures involving the buccal mucosa or appendix offer minimally invasive techniques and low morbidity with good short-term success. Drawbacks to appendiceal interposition include the availability and length of appendix, and 10-20% of patients may have insufficient appendix upon intra-operative assessment. Transureteroureterostomy is typically limited to extensive exonerations due to concerns of injury to the contralateral kidney, even with reported success rates > 90%. Ileal ureter may carry a risk of metabolic acidosis in patients with renal insufficiency along with bowel-related complications. Ileal ureter and autotransplantation are reserved for the most severe cases due to their high morbidity but do offer options for the complex patient.

CONCLUSION

Ureteral stricture disease not amenable to pyeloplasty, ureteroureterostomy or ureteroneocystostomy offers a challenge to urologist. Careful patient selection with pre-operative assessment of renal and bladder is vital to a successful operation with minimal complications.

The application of the "omental wrapping" technique with autologous onlay flap/graft ureteroplasty for the management of long ureteral strictures

Background

To present our experience with the "omental wrapping" technique in laparoscopic and robotic ureteroplasty using onlay flaps or grafts for the management of long proximal or middle ureteral strictures.

Methods

This is a retrospective review of 25 patients with long proximal or middle ureteral strictures who underwent laparoscopic and robotic onlay flaps or grafts ureteroplasty using an omental flap to reinforce an anastomosis site between August 2018 and November 2019. Perioperative and follow-up data were collected.

Results

Sixteen laparoscopic procedures and nine robotic procedures were performed successfully. Sixteen patients underwent ureteroplasty with lingual mucosal graft (LMG), and nine patients with appendiceal onlay flap (AOF). The median stricture length was 4 cm (range, 2-6 cm). The mean operative time (OT) was 220.5±50.6 min, the estimated blood loss (EBL) was 66.0±38.9 mL, and the length of hospital stay (LHS) was 8.0±3.6 days. In the LMG group, four patients had tongue numbing and one had an oral ulcer, which relieved itself gradually without intervention. Two patients in the LMG group and four patients in the AOF group experienced urinary tract infection, and all responded well to antibiotic treatment. There were no complications attributed to "omental wrapping". The mean follow-up was 16.3±4.8 months. According to the standards regarding improvement in clinical symptoms, relief of obstruction radiologically and a stable estimate glomerular filtration rate, our surgical success rate was 100%.

Conclusions

The "omental wrapping" technique in laparoscopic and robotic onlay flaps or grafts ureteroplasty for long proximal or middle ureteral strictures is an efficient, safe, reproducible and simple technique.

Robotic Repair of Ureteral Strictures: Techniques and Review

PURPOSE OF REVIEW

To provide an overview and description of the different surgical techniques for the robotic repair of ureteral strictures.

RECENT FINDINGS

The robotic repair of ureteral stenosis has emerged as a useful option for treating strictures unsuitable for endoscopic resolution with good results, lower morbidity, and faster recovery than open techniques. Depending on the stricture's length and location, the reconstructive options are reimplantation, psoas hitch, Boari flap, ureteroureterostomy, appendiceal onlay flap, buccal mucosa graft (BMG) ureteroplasty, ileal replacement, or renal autotransplantation. The robotic approach offers a magnified vision and the possibility of adding near-infrared fluorescence (NIRF) imaging, indocyanine green (ICG), and Firefly^TM to facilitate the technique. Multicenter studies with extended follow-up still have to confirm the good results obtained in published case series. Robotic reconstructive techniques are useful for repairing ureteral strictures, obtaining good functional results with less morbidity and faster recovery than open procedures.

Biodegradable Stent with mTOR Inhibitor-Eluting Reduces Progression of Ureteral Stricture

In this study, we investigated the effect of mTOR inhibitor (mTORi) drug-eluting biodegradable stent (DE stent), a putative restenosis-inhibiting device for coronary artery, on thermal-injury-related ureteral stricture in rabbits. In vitro evaluation confirmed the dose-dependent effect of mTORi, i.e., rapamycin, on fibrotic markers in ureteral component cell lines. Upper ureteral fibrosis was induced by ureteral thermal injury in open surgery, which was followed by insertion of biodegradable stents, with or without rapamycin drug-eluting. Immunohistochemistry and Western blotting were performed 4 weeks after the operation to determine gross anatomy changes, collagen deposition, expression of epithelial–mesenchymal transition markers, including Smad, α-SMA, and SNAI 1. Ureteral thermal injury resulted in severe ipsilateral hydronephrosis. The levels of type III collagen, Smad, α-SMA, and SNAI 1 were increased 28 days after ureteral thermal injury. Treatment with mTORi-eluting biodegradable stents significantly attenuated thermal injury-induced urinary tract obstruction and reduced the level of fibrosis proteins, i.e., type III collagen. TGF-β and EMT signaling pathway markers, Smad and SNAI 1, were significantly modified in DE stent-treated thermal-injury-related ureteral stricture rabbits. These results suggested that intra-ureteral administration of rapamycin by DE stent provides modification of fibrosis signaling pathway, and inhibiting mTOR may result in fibrotic process change.

Robotic assisted reconstruction for complications following urologic oncologic procedures

Despite technical refinements in urologic oncologic surgery, complications are inevitable and often carry significant morbidity. Similar to oncologic surgery, reconstructive surgery has realized a paradigm shift from mainly open to an increasingly minimally invasive approach. Robotic assisted surgery has facilitated this transition as it mitigates some of the limitations of traditional laparoscopy. With continued technological advances in robotic technology along with improved training and experience, the breadth and complexity of cases expand annually. Few head to head trials exist and data is overall heterogeneous. Herein, we review and summarize the currently available literature describing robotic assisted reconstruction for complications following urologic oncologic procedures.

Etiology and Ureteral Reconstruction Strategy for Iatrogenic Ureteral Injuries: A Retrospective Single-Center Experience

OBJECTIVE

To analyze the etiology, characteristics, and ureteral reconstruction strategies of iatrogenic ureteric injuries in a high-volume center.

METHODS

Between September 2010 and August 2019, we retrospectively collected patients who underwent ureteral reconstruction due to iatrogenic ureteric injuries. Patient profiles, laboratory data, imaging studies, perioperative data, and complications were recorded.

RESULTS

Sixty-eight patients were enrolled in this study. The upper, middle, and lower thirds of the ureter were affected in 30, 2, and 36 cases, respectively. Of the 68 ureteric injuries, 69.1% occurred during urological procedures, followed by gynecological procedures, general surgery, radiotherapy, and orthopedic surgery. The majority of urological injuries (41, 87.2%) occurred due to stone removal. There was a significant difference in the age, sex, and location of ureteric injuries between the urological and nonurological groups. The median follow-up time was 17.9 months. The overall symptom remission rate was 91.2% and ranged from 87.5 to 100% for different reconstructive surgeries.

CONCLUSIONS

Urological procedures were the most common cause of iatrogenic ureteric injury; thus, extra care should be taken. Timely detection and appropriate treatment of the ureteric injuries are necessary. Treatment strategies should be depended on the location and length of injury.

Laparoscopic and robotic ureteroplasty using onlay flap or graft for the management of long proximal or middle ureteral strictures: our experience and strategy

PURPOSE

To present our experience of laparoscopic and robotic ureteroplasty using onlay flap or graft for the management of long proximal or middle ureteral strictures and summarize our treatment strategies for these challenging scenarios.

METHODS

From March 2018 to January 2020, 53 patients with long proximal/middle ureteral strictures (2-6 cm) who underwent laparoscopic or robotic onlay flap/graft ureteroplasty were retrospectively enrolled. Different reconstruction techniques were chosen based on our management strategy: pelvic flap (PF) was the first choice for proximal stricture if pelvic tissue was sufficient for repair, while appendiceal flap (AF) was preferred over oral mucosa graft for both proximal and middle strictures.

RESULTS

A total of 28 PFs, 9 AFs and 16 lingual mucosa grafts (LMGs) onlay ureteroplasty were performed successfully, with 33 laparoscopic procedures and 20 robotic procedures being undertaken. No intraoperative complications or conversion occurred. The median stricture length was 4 cm (range 2-6 cm). Compared with laparoscopic procedures, robotic procedures showed significantly shorter operative time (P = 0.008), shorter postoperative hospital stay (P = 0.011) but higher hospital cost (P < 0.001). At a mean follow-up of 12.8 months, the overall success rate was 94.3%. There was no difference in postoperative complications or the success rate between the approaches.

CONCLUSION

Laparoscopic and robotic onlay flap/graft ureteroplasty can be safe and feasible to repair long proximal/middle ureteral strictures while robotic procedures showed higher efficiency, faster recovery but higher cost. Our algorithmic strategies may provide beneficial references for their standardization and dissemination into clinical care.

Appendiceal Interposition for Ureteral Stricture Disease: Technique and Surgical Outcomes

OBJECTIVE

To report our initial experience with ureteral appendiceal interposition (UAI) in a series of adult patients undergoing ureteral reconstruction for ureteral stricture.

METHODS

We retrospectively collected data of patients who underwent UAI for ureteral stricture disease from December 2015 to March of 2020. Success of surgery was defined as one that required no subsequent procedural intervention for recurrent ureteral stricture disease, or loss of kidney function.

RESULTS

Eleven patients underwent UAI for ureteral stricture. Etiologies for stricture disease included radiation exposure, nephrolithiasis, and iatrogenic injury. Median follow-up was 363 days. Three patients had Clavien-Dindo class III complications during their hospitalization. No patient required repeat intervention due to recurrent ureteral stricture disease. On imaging, 9 patients had no obstruction on Lasix renal scan postoperatively, or improvement in hydronephrosis on CT scan. Two patients with poor renal function preop continued to show poor function after surgery.

CONCLUSION

The use of the appendix is a safe and feasible option for ureteral reconstruction in appropriately selected adult patients when primary ureteral repair is not possible.

[Robot-assisted laparoscopic upper urinary tract reconstruction surgery: A review of 108 cases by a single surgeon]

OBJECTIVE

To summarize the experiences and outcomes of 108 robot-assisted laparoscopic upper urinary tract reconstruction surgeries conducted by a single surgeon.

METHODS

We consecutively and retrospectively reviewed 108 patients who underwent robot-assisted laparoscopic upper urinary tract reconstruction surgeries by a single surgeon from November 2018 to January 2020. The patient demographics, perioperative variables, postoperative complications and follow-up data were recorded. Fifty-three modified dismembered pyeloplasties (MDP), 11 spiral flap pyeloplasties (SFP), 11 ure-teroureterostomies (UUT), 4 lingual mucosal onlay graft ureteroplasties (LMU), 5 appendiceal onlay flap ureteroplasties (AU), 11 ureteral reimplantations (UR), 6 Boari flap-Psoas hitch surgeries (BPS) and 7 ileal ureter replacements (IUR) were enrolled finally. The success was defined as the improvement in subjective pain levels, and the improvement in the degree of hydronephrosis at ultrasound.

RESULTS

All the surgeries were successfully completed without open or laparoscopic conversion. The median operative time was 141 min (range: 74-368 min), median blood loss was 20 mL (range: 10-350 mL) and median hospital stay was 4 d (range: 3-19 d) in MDP group, with the success rate of 94.3%. The median operative time was 159 min (range: 110-222 min), median blood loss was 50 mL (range: 20-150 mL) and median hospital stay was 5 d (range: 3-8 d) in SFP group, with the success rate of 100%. The median operative time was 126 min (range: 76-160 d), median blood loss was 20 mL (range: 10-50 mL) and median hospital stay was 5 d (range: 4-9 d) in UUT group, with the success rate of 100%. The median operative time was 204 min (range: 154-250 min), median blood loss was 30 mL (range: 10-100 mL) and median hospital stay was 6 d (range: 4-7 d) in LMU group, with the success rate of 100%. The median operative time was 164 min (range: 135-211 min), median blood loss was 75 mL (range: 50-200 mL) and median hospital stay was 8.5 d (range: 6-12 d) in AU group, with the success rate of 100%. The median operative time was 149 min (range: 100-218 min), median blood loss was 20 mL (range: 10-50 mL) and median hospital stay was 7 d (range: 5-10 d) in UR group, with the success rate of 90.9%. The median operative time was 166 min (range: 137-205 min), median blood loss was 45 mL (range: 20-100 mL) and median hospital stay was 5 d (range: 4-41 d) in BPS group, with the success rate of 83.3%. The median operative time was 270 min (range: 227-335 min), median blood loss was 100 mL (range: 10-100 mL) and median hospital stay was 7 d (range: 5-26 d) in IUR group, with the success rate of 85.7%.

CONCLUSIONS

The surgeon performed and modified numerous complicated upper urinary tract reconstruction surgeries by the robotic platform, which facilitated the development of the standardized upper urinary tract reconstruction surgical technique.

Onlay Repair Technique for the Management of Ureteral Strictures: A Comprehensive Review

Ureteroplasty using onlay grafts or flaps emerged as an innovative procedure for the management of proximal and midureteral strictures. Autologous grafts or flaps used commonly in ureteroplasty include the oral mucosae, bladder mucosae, ileal mucosae, and appendiceal mucosae. Oral mucosa grafts, especially buccal mucosa grafts (BMGs), have gained wide acceptance as a graft choice for ureteroplasty. The reported length of BMG ureteroplasty ranged from 1.5 to 11 cm with success rates of 71.4%-100%. However, several studies have demonstrated that ureteroplasty using lingual mucosa grafts yields better recipient site outcomes and fewer donor site complications than that using BMGs. In addition, there is no essential difference in the efficacy and complication rates of BMG ureteroplasty using an anterior approach or a posterior approach. Intestinal graft or flap ureteroplasty was also reported. And the reported length of ileal or appendiceal flap ureteroplasty ranged from 1 to 8 cm with success rates of 75%-100%. Moreover, the bladder mucosa, renal pelvis wall, and penile/preputial skin have also been reported to be used for ureteroplasty and have achieved satisfactory outcomes, but each graft or flap has unique advantages and potential problems. Tissue engineering-based ureteroplasty through the implantation of patched scaffolds, such as the small intestine submucosa, with or without cell seeding, has induced successful ureteral regeneration structurally close to that of the native ureter and has resulted in good functional outcomes in animal models.

A Multi-Institutional Experience With Robotic Appendiceal Ureteroplasty

OBJECTIVE

To report a multi-institutional experience with robotic appendiceal ureteroplasty.

METHODS

This is a retrospective review of 13 patients undergoing right appendiceal flap ureteroplasty at 2 institutions between April 2016 and October 2019. The primary endpoint was surgical success defined by the absence of flank pain and radiographic evidence of ureteral patency.

RESULTS

Eight of 13 (62%) underwent appendiceal onlay while 5/13 (38%) underwent appendiceal interposition. Mean length of stricture was 6.5 cm (range 1.5-15 cm) affecting anywhere along the right ureter. Mean operative time was 337 minutes (range 206-583), mean estimated blood loss was 116 mL (range 50-600), and median length of stay was 2.5 days (range 1-9). Balloon dilation was required in 1/12 (8%). One patient died on postoperative day 0 due to a sudden cardiovascular event. Otherwise, there were no complications (Clavien-Dindo > 2) within 30 days from surgery. At a mean follow up of 14.6 months, 11/12 (92%) were successful.

CONCLUSION

Robotic appendiceal ureteroplasty for right ureteral strictures is a versatile technique with high success rates across institutions.

Appendiceal Onlay Flap Ureteroplasty for the Treatment of Complex Ureteral Strictures: Initial Experience of Nine Patients

Purpose: To evaluate the onlay technique using the appendix for ureteral reconstruction and describe the initial experience of nine operations performed by one surgeon. Methods: Nine patients with complex ureteral strictures who underwent appendiceal onlay flap ureteroplasty since May 2019 were recruited from our RECUTTER database. There were seven men and two women, with a mean age of 38.9 years; four patients underwent robot-assisted laparoscopic surgery, and five patients underwent traditional laparoscopic surgery. All patients had iatrogenic injuries of the ureter after treatment of stone disease. Seven patients had proximal ureteral strictures, and two had midureteral strictures. The mean stricture length of the nine patients was 3.9 (range 3-4.5) cm. Nephrostomy was performed in seven patients before they presented to our center, and the other two patients had indwelling Double-J ureteral stents. Results: All nine operations were effectively completed without open conversion. The mean operation time was 182 (range 135-220) minutes, the mean estimated blood loss was 71 (range 20-100) mL, and the mean length of postoperative hospital stay was 9 (range 6-12) days. No postoperative complications of high grade (Clavien-Dindo III and IV) occurred within 30 days of surgery. All the patients had their Double-J ureteral stents and nephrostomy tubes removed after complete ureteroscopy and upper urinary tract urodynamic examination or CTU, which showed that the anastomosis healed well and that the urinary tract was unobstructed, respectively. The objective success rate was 100% (all the patients had endoscopic and radiographic resolution of their ureteral strictures). The subjective success rate was 88.9% (one patient developed recurrent back discomfort and a 0.5 cm calculus was found in her renal pelvis). Conclusions: Appendiceal onlay flap ureteroplasty is a viable and effective technique for treating complex proximal and middle ureteral strictures at the right side.

Ureteral substitution with appendix

OBJECTIVE

To study the long-term results of ureteral reconstruction with the appendix in patients with long ureteral strictures.

METHODS

From 1998 to 2019, 26 patients were operated with substitution of extended defects of the ureter with the appendix. There were 22 women and four men (mean age 44.7 ± 11.3 years). One patient had stricture of the lumbar ureter because of a gunshot wound. He underwent substitution of the upper third of the right ureter with the appendix. In the other cases, we carried out substitution of the pelvis part of the ureter with appendix, in four cases from the left side. In the last 22 cases, a novel surgical technique for better appendicovesical anastomosis was carried out: a flap was dissected from the dome of the cecum to increase the diameter of anastomosis.

RESULTS

The postoperative follow-up period was from 1 to 21 years. A stricture of uretero-appendical anastomosis developed in four patients (15.4%). Resection of stricture and re-anastomosis was carried out in one case. In another two cases associated with similar complications, endoureterotomy and ureteral stenting were carried out. One patient was managed with percutaneous nephrostomy. Kidney function was restored in all patients. Good short-term results were achieved in 22 patients (84.6%) and long-term (from 1 to 21 years) results in 25 patients (96.2%).

CONCLUSIONS

In patients with long ureteral stricture, the use of the appendix can help to restore the function of the upper urinary tract.

Intestinal interposition for complex ureteral reconstruction: A comprehensive review

Long ureteral defects have remained a challenge to urologists for a long time. Bowel interposition, including ileal ureter, appendiceal interposition and reconfigured colon substitution, has gained wide acceptance, even though it is a complicated procedure and associated with some potential complications. Mucus obstruction and metabolic disorders are common complications of intestinal substitution. To circumvent these troubles, modified techniques, such as tapering the bowel graft, intestinal onlay flap and the Yang-Monti procedure, are used. In particular, Yang-Monti ileal ureter replacement is a highly effective option for ureteral reconstruction, and the incidence of complications would be significantly reduced in select patients. After being combined with the Boari flap or psoas hitch technique, the length of intestinal segment used can also be significantly reduced. Most recent long-term results suggest that ileal ureter replacement with antireflux anastomosis seems to be remarkably free of complications, and we highly praise the distal nipple valve technique. Appendiceal interposition is available for patients with normal appendix, and usually this procedure is limited to reconstructing the right ureter. Appendiceal onlay ureteroplasty has emerged as a feasible and effective option to manage patients with complex proximal and mid-ureteral strictures of the right side. The colon is rarely used for ureteral reconstruction because of its large caliber and mucous surface area. However, a reconfigured colon segment is a good substitute to reconstruct long-segment ureteral defects, and long-term follow up confirmed minimal complications and improved renal function. This review provides a comprehensive perspective on complex ureteral reconstruction and replacement using intestinal segments, in particular, ileal ureter replacement.

[Advances in surgical repair of ureteral injury]

Ureteral injury can be classified as iatrogenic or traumatic, which represents a rare but challenging field of reconstructive urology. Due to their close proximity to vital abdominal and pelvic organs, the ureters are highly susceptible to iatrogenic injury, while ureteral injury caused by external trauma is relatively rare. The signs of ureteric injury are difficult to identify initially and often present after a delay. The treatment of ureteral injury, which is depended on the type, location, and degree of injury, the time of diagnosis and the patient's overall clinical condition, ranges from simple endoscopic management to complex surgical reconstruction. And long defect of the ureter presents much greater challenges to urologists. Ureterotomy under endoscopy using laser or cold-knife is available for the treatment of 2-3 cm benign ureteral injuries or strictures. Pyeloplasty is an effective treatment for ureteropelvic junction obstruction and some improved methods showed the possibility of repairing long-segment (10-15 cm) stenosis. Proximal and mid-ureteral injuries or strictures of 2-3 cm long can often be managed by primary ureteroureterostomy. When not feasible due to ureteral defects of longer segment, mobilization of the kidney should be considered, and transureteroureterostomy is alternative if the proximal ureter is of sufficient length. And autotransplantation or nephrectomy is regarded as the last resorts. Most of the injuries or strictures are observed in the distal ureter, below the pelvic brim, and are usually treated with ureteroneocystostomy. A non-refluxing technique together with a ureteral nipple or submucosal tunnel method, is preferable as it minimizes vesico-ureteral reflux and the risk of infection. In order to cover a longer distance, ureteroneocystostomy in combination with a psoas hitch (covering 6-10 cm of defect) or a Boari flap (covering 12-15 cm) is often adopted. Among various ureteral replacement procedures, only intestinal ureteral substitution, which includes ileal ureter, appendiceal interposition and reconfigured colon substitution, has gained wide acceptance when urothelial tissue is insufficient. Ileal ureter can be used to replace the ureter of >15 cm defect and even to replace the entire unbilateral ureter or bilateral ureter. Laparoscopic and robotic-assisted techniques are increasingly being employed for ureteral reconstruction and adopted with encouraging results.

Robotic Ureteral Reconstruction in the Pediatric Population

Robot-assisted laparoscopic (RAL) surgery is a safe, minimally invasive technique that has become more widely used in pediatric urology over recent decades. With several advantages over standard laparoscopy, robotic surgery is particularly well-suited to reconstructive surgery involving delicate structures like the ureter. A robotic approach provides excellent access to and visualization of the ureter at all levels. Common applications include upper ureteral reconstruction (e.g., pyeloplasty, ureteropelvic junction polypectomy, ureterocalicostomy, and high uretero-ureterostomy in duplex systems), mid-ureteral reconstruction (e.g., mid uretero-ureterostomy for stricture or polyp), and lower ureteral reconstruction (e.g., ureteral reimplantation and lower ureter-ureterostomy in duplex systems). Herein, we describe each of these robotic procedures in detail.

Laparoscopic appendiceal interposition pyeloplasty for long ureteric strictures in children

INTRODUCTION

The management of long ureteric strictures is very challenging, and ureteral substitution is necessary when end-to-end anastomosis can not be accomplished.

OBJECTIVE

To evaluate the mid-term results of laparoscopic appendiceal interposition pyeloplasty in children with long ureteric strictures.

METHODS

Between March 2010 and September 2016 four patients (median age 24 months, male/female 3/1) underwent laparoscopic appendiceal interposition pyeloplasty at the current hospital. Two patients had previously failed pyeloplasty, one had a traffic injury, and one had iatrogenic ureteral injury (Summary Table). The intraoperative, postoperative and follow-up results were analyzed. Success was defined as clinical (subjective) and radiologic (objective) resolution of the stricture.

RESULTS

All surgeries were successfully completed without conversion. The mean stricture length was 4.5 cm. Two cases were right-sided strictures, and two were left-sided. The mean operative time and estimated blood loss were 238.5 min and 25.0 ml, respectively. No intraoperative complication was encountered. No Grade 3 or Grade 4 complication was observed after surgery. One was anastomosed in the antiperistaltic manner and three were in the isoperistaltic fashion. The mean postoperative hospital stay was 7.3 days. The success rate was 100% at a mean follow-up duration of 33.8 months.

DISCUSSION

There is no consensus on the best surgical approach for long ureteric strictures. Ureteric replacement with intestinal segments or kidney autotransplantation is a viable alternative treatment to long ureteric strictures. However, both methods are technically challenging with significant complications. Appendiceal interposition to restore ureteral continuity has been described in adult patients. The current results demonstrated that laparoscopic appendiceal interposition pyeloplasty is a safe and feasible minimally invasive approach for the treatment of long ureteral strictures in children.

CONCLUSIONS

Laparoscopic appendiceal interposition pyeloplasty was a viable minimally invasive alternative for children with long ureteric strictures on both left and right sides. Both isoperistaltic or antiperistaltic anastomosis were feasible.

Robotics and urologic reconstructive surgery

Minimally invasive surgery has made a profound impact on how urologists approach the challenges in reconstruction of the urinary tract. The advent of laparoscopic approaches to reconstructive urology have demonstrated comparable outcomes to open surgery with improved morbidity. The recent adoption of robotic surgery has seen further advancements such as improved visibility and, freedom of movement, and an easier technical learning curve. With these advantages, more reconstructive urology procedures are being performed robotically. Herein, we review reconstructive urology procedures for which robotics have been applied.

Management of iatrogenic ureteral injury and techniques for ureteral reconstruction

PURPOSE OF REVIEW

Ureteral reconstruction is still a sophisticated approach. Because of an increase in endoscopic procedures for kidney and ureteral stone treatment, radiation therapy and pelvic surgery, ureteral strictures are more frequently observed. Short proximal and distal strictures can be reconstructed by using the renal pelvis or urinary bladder. New techniques are needed for reconstruction of long strictures as well as those located in the middle ureter.

RECENT FINDINGS

This article summarizes very recent studies from 2014, investigating new techniques and their functional outcome of procedures for ureteral reconstruction. In an open reconstruction, some new techniques to reconstruct full-length ureter defects using bladder flaps or by intestinal onlay techniques were described. In addition, laparoscopic and robotic reconstruction methods as well as single site procedures demonstrated feasibility. Visualizing the ureter using near-infrared fluorescence techniques for prevention of ureteral injuries is also a new aspect. Future targets focus on the development of artificial transplants by tissue engineering for ureteral reconstruction.

SUMMARY

Novel open and minimally invasive techniques for reconstruction of full-length and middle ureter strictures demonstrated feasibility in the past year. Although reasonable outcomes were reported, current results are significantly compromised by short-term follow-up. To date, artificial transplants remain experimental.

[Management of ureteral strictures and hydronephrosis]

Patients who develop hydronephrosis due to an acute cause often have colic-like pain but hydronephrosis secondary to a chronic cause is often asymptomatic. Ureteral obstruction can be due to a variety of intrinsic and extrinsic causes, such as trauma, radiation, iatrogenic injury, urolithiasis, malignancies and congenital causes. Management planning is dictated by the underlying cause, patient comorbidity and life expectancy. Malignant ureteral obstructions can be managed with segmental metal stents with advantages in the quality of life and provide an alternative to long-term treatment with a DJ stent. Endoscopic balloon dilatation and endoureterotomy are options for benign ureteral strictures up to 2 cm in length. For longer benign strictures there are a number of reconstructive techniques, which can also be performed by laparoscopic or robot-assisted approaches at specialized centers.