Buccal Mucosa Graft for Ureteral Stricture Substitution: Initial Experience

Ureteroplasty with buccal mucosa graft without omental wrap: an effective method to treat ureteral strictures

PURPOSE

Successful treatment options for ureteral strictures are limited. Surgical options such as ileal interposition and kidney autotransplantation are difficult and associated with morbidity and complications. Techniques such as Boari flap and psoas hitch are limited to distal strictures. Only limited case studies on the success of open buccal mucosa graft (BMG) ureteroplasty exist to this date. The purpose of this study was to evaluate the success of open BMG ureteroplasty without omental wrap.

METHODS

In this single-center retrospective study between July 2020 and January 2023, we included 14 consecutive patients with ureteric strictures who were treated with open BMG ureteroplasty without omental wrap. The primary outcome was the success of open BMG ureteroplasty. Further endpoints were complications and hospital readmission. Outcome variables were assessed by clinical examination, kidney sonography, and patient anamnesis.

RESULTS

Out of 14 patients, 13 were stricture and ectasia-free without a double-J stent at a median follow-up of 15 months (success rate 93%). No complications were observed at the donor site, and the complication rate overall was low with 3 out of 14 patients (21%) having mild-to-medium complications.

CONCLUSIONS

Open BMG ureteroplasty without omental wrap is a successful and feasible technique for ureteric stricture repair.

Oral mucosal graft ureteroplasty versus ileal ureteric replacement: a meta-analysis

OBJECTIVES

To describe outcomes of oral mucosal graft ureteroplasty (OMGU) and ileal ureter replacement (IUR) and determine the relative merits of both procedures.

METHODS

Databases (including PubMed, Embase and Cochrane) were interrogated for eligible trials that assessed outcomes of OMGU or IUR from 2000 to 30 July 2022. The variables analysed were reconstruction success rates, stricture length, hospital stays, perioperative complications and long-term complications.

RESULTS

A total of 23 single-arm studies were included. The pooled reconstruction success rates for OMGU and IUR were 94.9% (95% confidence interval [CI] 91.0%-97.7%) and 85.8% (95% CI 81.0%-90.0%), respectively. Stricture length of patients in the OMGU and IUR groups were 3.73 (95% CI 3.17-4.28) and 11.55 (95% CI 9.82-13.29) cm, respectively. The maximal stricture length repaired by OMGU was 8 cm. The hospital stays were 5.85 (95% CI 3.88-7.82) and 11.55 (95% CI 6.93-16.17) days in the OMGU and IUR groups, respectively. The incidences of low-grade postoperative complications were 13.6% (95% CI 6.9%-20.3%) and 27.3% (95% CI 19.5%-35.1%), high-grade postoperative complications were 4.6% (95% CI 1.8I-8.5%) and 13.0% (95% CI 9.4%-17.1%), and long-term complications (occurred at > 3months) were 9.0% (95% CI 1.7%-20.0%) and 35.4% (95% CI 25.8%-45.6%) in the OMGU and IUR groups, respectively.

CONCLUSION

An OMGU is an effective, minimally invasive, and safe alternative to IUR for the management of long ureteric strictures. OMGU was the preferred treatment for long ureteric strictures, especially obstructed ureter segments of ≤8 cm.

Treatment of long ureteric strictures with a free peritoneal graft: long-term results

ZIEL DER STUDIE

Beschreibung einer neuen Technik zur Rekonstruktion von komplexen Ureterstrikturen unter Verwendung eines freien Peritoneallappens.

MATERIAL UND METHODEN

Zwischen 2006 und 2021 behandelten wir 11 Patienten mit langen komplexen Harnleiterstrikturen, die in 9 Fällen den mittleren- und in 2 Fällen den proximalen Harnleiter betrafen. Die Länge der Strikturen variierte von 3 bis 12 cm (Mittelwert 7 cm). In drei Fällen handelte es sich um eine retroperitoneale Fibrose nach einem gefäßchirurgischen Eingriff, in zwei Fällen um einen Morbus Ormond, in vier Fällen um eine ausgedehnte Resektion großer Harnleitertumoren, in drei Fällen um wiederholte endoskopische Eingriffe bei Harnsteinen und in einem Fall um eine viermal fehlgeschlagene Pyeloplastik. Der Harnleiter wurde längs gespalten, ein freier Peritoneallappen aus dem nahe gelegenen gesunden Bauchfell entnommen und nach Positionierung eines Harnleiterkatheters als Onlay-Patch mit einer fortlaufenden Naht an der verbleibenden Harnleiterplatte fixiert. Der Ureter wurde zuletzt mit Omentum gedeckt.

ERGEBNISSE

Die Nachbeobachtungszeit reichte von 12 bis 122 (Mittelwert 61,6) Monate. Sieben Patienten waren nach 12, 18, 60, 78, 98, 99 und 122 Monaten (Mittelwert 69,5 Monate) rezidivfrei, ohne Erweiterung des oberen Harntrakts und mit normaler Nierenfunktion. Bei vier Patienten kam es zu einem Rezidiv: Bei einem Patienten wurde das Rezidiv nach 60 Monaten ohne Symptome und mit leichter Hydronephrose festgestellt, ohne dass eine Operation erforderlich war. Bei einem Patienten mit Morbus Ormond trat das Rezidiv 6 Monate nach dem Eingriff symptomlos im distalen Teil des 10 cm langen Omlays auf. Es wurde eine Resektion des stenotischen Segments mit Psoas-Hitch durchgeführt. Bei den beiden anderen Patienten trat 3 und 6 Monate nach dem Eingriff eine Obstruktion unterhalb des rekonstruierten Segments mit Hydronephrose auf, ohne dass die Nierenfunktion beeinträchtigt war. Bei diesen Patienten wurde keine weitere Operation durchgeführt. Die Limitation dieser Studie besteht in der kleinen Studiengröße, die auf die strenge Indikationsstellung zurückzuführen ist.

SCHLUSSFOLGERUNGEN

Die beschriebene Technik ermöglicht den Erhalt der verbleibenden Gefäßversorgung des Harnleiters und stellt eine praktikable und nützliche Alternative zu Nephrektomie, Ileum-Ureter, Uretero-Uretero-Stomie und Autotransplantation in hochselektierten Fällen dar.

Reconstruction of a partial esophageal defect using tunica vaginalis and buccal mucosa autograft: an experimental study in mongrel dogs

In veterinary clinics, esophageal reconstruction is essential in many clinical situations. In this study, two autografts, the tunica vaginalis (TV) and the buccal mucosa (BM), were proposed to reconstruct a semi-circumferential cervical esophageal defect in dogs. This study aimed to verify whether these two grafts could successfully patch esophageal defects. Twelve male mongrel dogs were divided into two groups. Following cervical esophagoplasty, the defective area was patched with either a TV or a BM graft. Comprehensive clinical, serum biochemical, and histological analyses were performed to evaluate the two grafts. Throughout the study (120 days), the dogs survived the procedure well with minor complications. The lumen of the patched areas was covered with mucosa, with slight scar retraction. Compared with that of the natural esophagus, the average relative luminal diameter was not significantly decreased. Importantly, the measured cortisol and inflammatory marker levels returned to the preoperative levels after 14 days. Although histological examination revealed that both grafts repaired the esophageal defect with complete re-epithelialization, the BM graft showed a histological structure similar to that of the natural esophagus. Both grafts effectively repaired the esophageal defect with minor complications; therefore, both are recommended as promising low-cost clinical alternatives for cervical esophagoplasty in dogs.

Robotic versus laparoscopic ureteroplasty with a lingual mucosa graft for complex ureteral stricture

PURPOSE

Ureteroplasty with a lingual mucosa graft (LMG) for complex ureteral stricture was reported promising. We aimed to compare outcomes of robotic versus laparoscopic ureteroplasty using a LMG (RU-LMG vs. LU-LMG, respectively).

METHODS

From October 2018 to January 2021, 32 ureteroplasties using LMGs were performed by one experienced surgeon, including 16 robotic and laparoscopic procedures each. Patient demographics and peri-operative, post-operative, and follow-up data were prospectively collected and compared.

RESULTS

The robotic group had a higher rate of previous reconstruction than the laparoscopic group (62.50% vs. 18.75%; p = 0.012). The stricture length was significantly longer in the robotic group (4.8 ± 1.2 cm) than the laparoscopic group (3.7 ± 1.2 cm; p = 0.013). All procedures were completed successfully without open conversion. The operative time was shorter in the robotic group (192 ± 54 min) than the laparoscopic group (254 ± 46 min; p = 0.001). The robotic group had a shorter length of post-operative stay (6.1 ± 2.4 d vs. 8.9 ± 4.3 d; p = 0.033) but a higher hospital cost (76,801 ± 17,974 vs. 42,214 ± 15,757 RMB; p < 0.001) than the laparoscopic group. The mean follow-up time was 21 ± 7 months for the robotic group and 29 ± 9 months for the laparoscopic group respectively (p = 0.014). No difference was detected in the success rate (93.75% and 100%, respectively; p = 0.309) and complication rate (18.75% and 31.25%, respectively; p = 0.414) between the robotic and laparoscopic groups.

CONCLUSION

Both RU-LMG and LU-LMG are feasible, effective, and safe for repair of complex ureteral strictures. RU-LMG had a shorter operative time and a shorter length of post-operative stay but a higher hospital cost.

Lingual Mucosal Graft Ureteroplasty for Long Proximal Ureteral Stricture: 6 Years of Experience with 41 Cases

BACKGROUND

Management of a long proximal ureteral stricture is challenging. Lingual mucosal graft ureteroplasty (LMGU) is a novel minimally invasive technique for ureteral reconstruction that avoids the morbidity of bowel interposition or autotransplantation.

OBJECTIVE

To evaluate the long-term effectiveness of LMGU for managing long, complex proximal ureteral strictures in a multi-institutional cohort of patients.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective study involved data for 41 patients treated with LMGU at three centers between June 2015 and January 2021.

SURGICAL PROCEDURE

LMGU was performed using either an onlay ureteroplasty in which the diseased ureter was incised ventrally and repaired with a lingual mucosal graft (LMG) to widen the ureteral lumen, or an augmented anastomotic technique in which the obliterated segment of the ureter was excised and reanastomosed primarily on dorsal side, and an LMG was placed on the ventral side.

MEASUREMENTS

Pre-, intra-, and postoperative variables and outcomes were assessed. A descriptive statistical analysis was performed.

RESULTS AND LIMITATIONS

Of 41patients, 40 were operated with laparoscopic procedures and one with a robot. Twenty-four (59%) patients underwent an onlay ureteroplasty, and 17 (41%) underwent an augmented anastomotic ureteroplasty. The reconstructed ureter was wrapped with omentum in 90% of cases. The median (range) stricture length was 4.8 cm (2.0-8.0), operative time was 166 min (98-306), and estimated blood loss was 65 ml (15-220). No open conversions and intraoperative complications occurred. At a median follow-up of 35 mo (range 13-80), the overall success rate was 97.6% (40/41).

CONCLUSIONS

LMGU is a safe, feasible, and effective long-term technique for managing long, complex proximal ureteral strictures.

PATIENT SUMMARY

We reported a novel technique for long proximal complex ureteral strictures using an onlay lingual mucosal graft (LMG). Our 6-yr outcomes demonstrate that onlay LMG ureteroplasty is a safe, feasible, and effective long-term procedure for ureteral reconstruction.

Robotic-assisted Lingual Mucosal Graft Ureteroplasty for the Repair of Complex Ureteral Strictures: Technique Description and the Medium-term Outcome

BACKGROUND

Robot-assisted autologous graft ureteroplasty provides another treatment option for complex ureteral strictures, circumventing ileal ureter or renal autotransplantation.

OBJECTIVE

To report the medium-term outcome of robotic ureteroplasty with a lingual mucosal graft (RU-LMG) for managing complex ureteral strictures.

DESIGN, SETTING, AND PARTICIPANTS

Between June 2019 and September 2020, 12 patients underwent RU-LMG. The perioperative variables were prospectively collected, and the outcomes were assessed.

SURGICAL PROCEDURE

After ureteral stricture dissection, the narrow segment was cut longitudinally, and a lingual mucosal graft (LMG) of the required length was harvested, followed by double-J stent placement and LMG ventral onlay anastomosis. If the diseased ureter required transection, posteriorly augmented ureteral anastomosis could be performed before LMG harvest. Finally, the anastomotic area was wrapped by the omental flap.

MEASUREMENTS

A descriptive statistical analysis was performed. The criteria for complete success included the absence of both clinical symptoms and obstruction on radiography.

RESULTS AND LIMITATIONS

Seven patients (58%) had a history of failed ureteral reconstruction. The mean (range) stricture length was 4.7 (3-6.5) cm, LMG length was 4.4 (3-7) cm, LMG width was 1.5 (1-2) cm, operative duration was 197.1 (130-346) min, estimated blood loss was 49.2 (10-200) ml, and the duration of postoperative hospitalization was 6 (4-14) d. No open conversions and intraoperative complications occurred. The median follow-up time was 15 mo (range: 13-27 mo). The overall success rate was 92% (11/12).

CONCLUSIONS

These medium-term follow-up results demonstrate that RU-LMG is a safe and feasible technique for repairing ureteral strictures.

PATIENT SUMMARY

Our study proves that robotic ureteroplasty with a lingual mucosal graft is a safe and feasible technique for ureteral reconstruction that can serve as another choice for managing long, complex ureteral strictures.

Buccal mucosal graft urethroplasty in male cats with traumatic complete urethral rupture

OBJECTIVE

To evaluate the feasibility of buccal mucosal graft urethroplasty for repairing complete urethral rupture in cats.

ANIMALS

15 male domestic shorthair cats with traumatic complete urethral rupture.

PROCEDURES

In each cat, a section of buccal mucosa was harvested, sutured, and formed into a tubule by use of an 8F indwelling catheter as support. This tubular graft was connected to both ruptured ends of the urethra to renew the urinary passage. The catheter was left in place until the absence of leakage was confirmed by positive contrast retrograde urethrography. After spontaneous urination was confirmed, cats were discharged from the hospital. Six months later, urethrography was repeated and owners were asked to score their cats' urinary function and quality of life.

RESULTS

13 cats recovered well following surgery, with no complications in the oral cavity or surgical site and no signs of difficulty or discomfort when urinating. Urethrography 2 weeks and 6 months after surgery revealed no stricture or leakage in the abdominal cavity. The 2 remaining cats developed a urethral stricture and underwent second surgery with a successful outcome. At the 6-month follow-up, 14 cats had only mild urinary signs, and 1 cat had incontinency. Owners indicated they were delighted (n = 14) or pleased (1) with their cats' quality of life.

CLINICAL RELEVANCE

Buccal mucosa was found to be a good source of graft tissue for performance of urethroplasty in male cats, yielding satisfactory outcomes with few postoperative complications. The described technique may be suitable for severe and complicated cases of urethral rupture in male cats.

Validation of robotic-assisted ureteroplasty with buccal mucosa graft for stricture at the proximal and middle ureters: the first comparative study

Although ureteroplasty with buccal mucosa graft for long-segmental ureteral stenosis has been developed long ago, evidence was still restricted to case series in published literature. This study aims to validate ureteroplasty with buccal mucosa graft (BMG) in long-segment stricture at the proximal and middle ureters under designed comparative methods. From April 2015 to January 2019, we performed robotic-assisted ureteroplasty with BMG with a two-phase design and compared ureteroplasty and BMG (phase 2 surgery) with endoscopic stenting (phase 1 surgery). Paired data of effective renal plasma flow (ERPF), glomerular filtration rate (GFR), hydronephrosis grade, and physical and psychological domains of the World Health Organization Quality of Life (WHOQOL)-BREF were compared. A total of 29 patients were enrolled, and only three (10%) patients had hydronephrosis resolution after treatment with endoscopic stenting (p = 0.250 to baseline). Compared to endoscopic ureteral stent, Hedges' g of ureteroplasty with BMG was 0.56 (95% CI 0.43-0.69), 0.63 (95% CI 0.46-0.80), 0.80 (95% CI 0.56-1.04), and 1.06 (95% CI 0.69-1.43) in EGFR, GFR, physical domain of WHOQOL-BREF, and psychological domain of WHOQOL-BREF, respectively (All significance; p < 0.001). After 12-month follow-ups, no recurrence of stricture was reported. In conclusion, Robotic-assisted ureteroplasty with BMG onlay is efficient in reconstruction of long-segment stricture of the proximal and middle ureters.

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.

Combined ureterocalicostomy with buccal mucosa graft ureteroplasty in complex upper ureteral stricture: A rare case of reconstruction

The treatment of a major and complex ureteric stricture requires the use of a bowel interposition or autotransplantation of the kidney, which is a major undertaking and remains the traditional option. Buccal mucosa is an established tissue for urethral reconstruction and can be used safely for the repair of narrowing of the ureter. This technique has been well documented in the literature; however, a combined ureterocalicostomy with buccal mucosa graft ureteroplasty has not yet been reported in literature. We report the case of a 59-year-old female who was diabetic and hypertensive presented with a long-length, complex upper ureteric stricture with recurrent pyelonephritis. A long stricture in the upper ureter measuring approximately 8 cm was successfully repaired by free buccal mucosal onlay patch graft over a double J stent with ureterocalicostomy. This technique can be used in salvaging kidneys with complex ureteric strictures along with fibrotic pelvis.

The Expanding Use of Buccal Mucosal Grafts in Urologic Surgery

The advent and success of buccal mucosal grafts as a substitution material in the urinary tract has changed the landscape of reconstructive urology. Due to its ease to harvest, low morbidity, and advantageous properties, there has been a growing number of applications for buccal mucosal grafts in upper and lower urinary tract reconstruction as well as genital reconstruction. In this article, we review the historical application and the evolution of buccal mucosal grafts and provide an up-to-date review on its utilization in urologic procedures.

Posteriorly Augmented Anastomotic Ureteroplasty with Lingual Mucosal Onlay Grafts for Long Proximal Ureteral Strictures: 10 Cases of Experience

Objective: To share the technique of posteriorly augmented anastomotic ureteroplasty with lingual mucosal onlay grafts for long proximal ureteral strictures as well as our initial experience with the technique. Methods: From October 2018 to September 2019, 10 cases of robotic and laparoscopic posteriorly augmented anastomotic ureteroplasty with lingual mucosal onlay grafts for long proximal ureteral strictures were recruited from our database of Reconstruction of Urinary Tract: Technology, Epidemiology and Result (RECUTTER). The perioperative and follow-up data were recorded. Complete success was defined as the absence of clinical symptoms, relieved stenosis on imaging, and a stable estimated glomerular filtration rate without serious complications. Results: All surgeries were completed without serious complications. There were eight laparoscopic surgeries and two robotic surgeries. The median length of defect after posteriorly augmented anastomosis was 3 cm (range, 3-5 cm). The median length of the lingual mucosa graft was 4 cm (range, 3-5 cm). The median operative time was 237 minutes (range, 189-310 minutes). The median estimated blood loss was 40 mL (range, 10-100 mL). The median postoperative length of stay was 7.5 days (range, 5-22 days). The Double-J stent was removed median 3.5 months (range, 2-7 months) after the surgery. At the median follow-up of 11 months (range, 7-20 months), all patients achieved the successful criteria of treatment. Conclusion: The posteriorly augmented anastomotic ureteroplasty with lingual mucosal onlay grafts for long proximal ureteral strictures is a feasible and safe technique, which may be an option especially for strictures marginally longer than those that can be safely repaired via end-to-end anastomosis.

Ileal ureter replacement: Early morbidity and long-term results

INTRODUCTION

Ileal ureter is a technique that consists of replacing the ureter by a segment of ileum to treat a long ureteric lesion or a lesion involving the lumbar ureter. The primary objective of our study was to assess the early perioperative morbidity of ileal ureter according to the Clavien-Dindo classification. The secondary objectives were to assess the morbidity and the medium- and long-term outcome of renal function.

MATERIALS AND METHODS

Single-centre retrospective study, collecting data from patients operated between February 2005 and October 2019. All patients who underwent ileal ureter replacement surgery in our unit were included in this analysis. The ureteric defect was longer than five centimetres and involved the pelvic and/or iliac and/or lumbar ureter. All ileal ureter replacements were performed by open surgery using isoperistaltic ileal grafts.

RESULTS

Twenty-one patients (11 women and 10 men) underwent total or subtotal, unilateral or bilateral ileal ureter replacement, corresponding to 25 kidneys. The grade III early postoperative complication rate was 9.5% (two cases) mainly consisting of bleeding. No grade IV or V complications were observed. With a mean follow-up of 85 months, long-term morbidity essentially consisted of infectious complications. No patients developed anastomotic strictures. Mean serum creatinine was 116.3μmol/L preoperatively, 105.6μmol/L one month postoperatively and 112.2μmol/L at last follow-up. Renal function was generally preserved or even improved, except for patients with preoperative renal failure.

CONCLUSION

Ileal ureter replacement is a surgical alternative associated with low morbidity and satisfactory long-term functional results.

LEVEL OF EVIDENCE

3.

Ileal Ureteral Substitution After "Panureteral Damage: A Devastating Complication of Forgotten Double-J Stent"

Background: Forgotten ureteral stent is frequently observed in urologic practice. It has serious consequences such as encrustation, stone formation, fragmentation, ureteral damage, and sepsis. Panureteral damage by forgotten stent is a major complication requiring complex reconstructive surgery. Case Presentation: We report a case of 66-year-old man with forgotten ureteral stent for 10 years, which caused panureteral damage. Ileal ureteral substitution was done and kidney was salvaged. Conclusion: Prolonged forgotten stent can cause panureteral fibrosis and requires complex surgical procedure such as ileal ureteral substitution.

A new technique for ureteral reconstruction using lingual mucosa grafts in a beagle model

PURPOSE

To investigate the feasibility of ureteral reconstruction using lingual mucosa graft (LMG) and evaluate the histological changes of the engrafted LMG in beagles.

METHODS

Twelve male beagle dogs were randomly divided into groups A, B and C (n = 4). A ventral ureteral defect was created by excising half of the ureteral wall. The length of the defect was 3 cm, 6 cm, and 10 cm in groups A, B, and C, respectively. The LMGs were harvested and employed to repair the ureteral defects in onlay fashion. Two dogs per group were sacrificed after 6 months, with additional two dogs per group sacrificed after 12 months. Intravenous urography (IVU) and macroscopic examination were performed to evaluate renal function and ureteral patency. Histological changes in the engrafted LMGs during the tissue incorporation process were assessed by histological analysis.

RESULTS

There were no postoperative complications. Only one dog in group C developed a mild stricture near the proximal anastomosis. In the remaining 11 animals, IVU showed normal renal function and a wide ureteral caliber without stricture or fistula. The diameter of the LMG-reconstructed ureter was greater than that of the proximal and distal ureter (each p value < 0.01). The LMGs survived in situ with newly formed capillaries. The epithelium of the lingual mucosa resembled the urothelium in postoperative 12 months.

CONCLUSION

This new technique for ureteral reconstruction using LMGs is feasible. This approach is a promising alternative clinical treatment for curing long ureteral strictures.

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.

Open ureteroplasty with buccal mucosa graft for long proximal strictures: A good option for a rare problem

Purpose

To report a single surgeon experience with one year follow-up after open ureteroplasty with buccal mucosa graft (OUBMG) in the rare situation of long segment proximal ureteral strictures.

Materials and Methods

Four patients with long segment proximal ureteral stricture underwent OU-BMG between February and July 2017. Functional outcome was assessed by pre- and postoperative serum creatinine, ultrasound and renal scintigraphy as well as patient reported outcomes.

Results

Four patients with an average stricture length of 4 cm underwent OU-BMG between February and July 2017. No major postoperative complications occurred. Retrograde uretero-pyelography 6 weeks postoperatively revealed a watertight anastomosis followed by immediate emptying of the renal pelvis and ureter in all four patients. Ureteroscopy at this time showed a wide lumen with well-vascularized pink mucosa. After a mean follow-up time of 12.5 (12–14) months, postoperative serum creatinine was unimpaired. Renal scintigraphy revealed no signs of renal obstruction. With regard to intraoral surgery, no difficulties with mouth opening or intraoral dryness or numbness were reported.

Conclusions

For patients with long segment ureteral strictures OU-BMG is a safe technique with excellent surgical and functional outcomes. Hence, the application of this technique should be encouraged and regarded as one of the standard options in case of this rare problem.

Robot-assisted distal ureteral reconstruction for benign pathology: Current state

Distal ureteral reconstruction for benign pathologies such as stricture disease or iatrogenic injury has posed a challenge for urologist as endoscopic procedures have poor long-term outcomes, requiring definitive open reconstruction. Over the past decade, there has been an increasing shift towards robot-assisted laparoscopy (RAL) with multiple institutions reporting their outcomes. In this article, we reviewed the current literature on RAL distal ureteral reconstruction, focusing on benign pathologies only. We present peri-operative data and outcomes on the most common technique, ureteral reimplantation, as well as adjunct procedures such as psoas hitch and Boari flap. Additionally, we present alternative techniques reported in the literature with some technical considerations. Lastly, we describe the outcomes of the comparative studies between open, laparoscopy, and RAL. Although the body of literature in this field is limited, RAL reconstruction of the distal ureter appears to be safe, feasible, and with some advantages over the traditional open approach.

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.

Contemporary management of ureteral strictures

Ureteral stricture disease is a luminal narrowing of the ureter leading to functional obstruction of the kidney. Treatment of strictures is mandatory to preserve and protect renal function. In recent times, the surgical management of ureteral strictures has evolved from open repair to include laparoscopic, robotic and interventional techniques. Prompt diagnosis and early first line intervention to limit obstructive complications remains the cornerstone of successful treatment. In this article, we discuss minimally invasive, endo-urological and open approaches to the repair of ureteral strictures. Open surgical repair and endoscopic techniques have traditionally been employed with varying degrees of success. The advent of laparoscopic and robotic approaches has reduced morbidity, improved cosmesis and shortened recovery time, with results that are beginning to mirror and in some cases surpass more traditional approaches.

Level of evidence: Not applicable for this multicentre audit.

Clinical reappraisal and state of the art of nephropexy

The diffusion of minimally invasive techniques for renal surgery has prompted a renewed interest in nephropexy which is indicated to prevent nephroptosis in symptomatic patients and to mobilize the upper ureter downward in order to bridge a ureteral defect. Recent publications have been reviewed to present the state of the art of the diagnosis and management of these two challenging conditions and to try to foresee the next steps. The evaluation of patients with mobile kidney can be made relying on diagnostic criteria such as ultrasound with color Doppler and measurement of resistive index, conventional upright X-ray frames after a supine uro-computerized tomography scan and both static and dynamic nuclear medicine scans, always with evaluation in the sitting or erect position. Laparoscopic nephropexy emerges as the current treatment option combining both objectively controlled repositioning of the kidney and resolution of symptoms with minimal invasiveness, low morbidity, and short hospital stay. The use of robotics is presently limited by its higher cost, but may increase in the future. Downward renal mobilization and nephropexy is a safe and versatile technique which has been adopted as a unique strategy or more often in combination with other surgical maneuvers in order to cope with complex ureteral reconstruction.

Adult iatrogenic ureteral injury and stricture-incidence 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 short- and 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.

Robot-assisted ureteral reconstruction - current status and future directions

Robotic surgery in the treatment in certain urological diseases has become a mainstay. With the increasing use of the robotic platform, some surgeries which were historically performed open have transitioned to a minimally invasive technique. Recently, the robotic approach has become more utilized for ureteral reconstruction. In this article, the authors review the surgical techniques for a number of major ureteral reconstuctive surgeries and briefly discuss the outcomes reported in the literature.

Use of ileum for complex ureteric reconstruction: Assessment of long-term outcome, complications, and impact on renal function

Introduction:

Defect in ureteral continuity can be due to various etiologies. The surgical options for management of complex long-segment ureteric defects are limited. Use of ileum is indicated in these cases; however, the technique is challenging and outcomes need to be assessed in detail.

Material and Methods:

It is an observational study conducted over 4 years. After preoperative optimization, ureteric reconstruction was performed using standard techniques of ileal interposition in cases of unilateral and bilateral long-segment ureteric defects. Patients were followed up at regular interval to assess outcomes and see for complications.

Results:

A total of 14 patients were studied. Two most common indications for performing ileal ureter were iatrogenic injury and radiation-induced strictures (5–5 cases). Most common site of ureteric involvement was lower and midureter seen in 6 cases. The mean length of the ileum used was 11.2 cm. Mean preoperative nadir creatinine level was 1.57 mg/dL in this study. Average postoperative creatinine level at 4-week follow-up was 1.75 mg/dL and 1.45 mg/dL and 1.37 mg/dL, at 3 and 12 months, respectively. The most common short-term complication was paralytic ileus and long-term complication was recurrent urinary tract infection UTI. There was no mortality.

Conclusion:

Ileal ureter is found to be relatively easy and safe surgery even in patients with borderline high creatinine. There was no worsening of renal function attributable to the conduit in this study. In patients with limited surgical options, it is a suitable alternative, rather than keeping patient on permanent percutaneous nephrostomy or regular stent change. Metabolic acidosis and mucous-associated complications such as pain, infection, and stone formation can be minimized by adherence to strict protocol.

Robotic Ureteral Reconstruction Using Buccal Mucosa Grafts: A Multi-institutional Experience

BACKGROUND

Minimally invasive treatment of long, multifocal ureteral strictures or failed pyeloplasty is challenging. Robot-assisted buccal mucosa graft ureteroplasty (RBU) is a technique for ureteral reconstruction that avoids the morbidity of bowel interposition or autotransplantation.

OBJECTIVE

To evaluate outcomes for RBU in a multi-institutional cohort of patients treated for revision ureteropelvic junction obstruction and long or multifocal ureteral stricture at three tertiary referral centers.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective study involved data for 19 patients treated with RBU at three high-volume centers between October 2013 and July 2016.

SURGICAL PROCEDURE

RBU was performed using either an onlay graft after incising the stricture or an augmented anastomotic repair in which the ureter was transected and re-anastomosed primarily on one side, and a graft was placed on the other side.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Preoperative, intraoperative, and postoperative variables and outcomes were assessed. A descriptive statistical analysis was performed.

RESULTS AND LIMITATIONS

The onlay technique was used for 79%, while repair was carried out using the augmented anastomotic technique for the remaining cases. The reconstruction was reinforced with omentum in 95% of cases. The ureteral stricture location was proximal in 74% and mid in 26% of cases. A prior failed ureteral reconstruction was present in 53% of patients. The median stricture length was 4.0cm (range 2.0-8.0), operative time was 200min (range 136-397), estimated blood loss was 95ml (range 25-420), and length of stay was 2 d (range 1-15). There were no intraoperative complications. At median follow-up of 26 mo, the overall success rate was 90%.

CONCLUSIONS

RBU is a feasible and effective technique for managing complex proximal and mid ureteral strictures.

PATIENT SUMMARY

We studied robotic surgery for long ureteral strictures using grafts at three referral centers. Our results demonstrate that robotic buccal mucosa graft ureteroplasty is a feasible and effective technique for ureteral reconstruction.

Robotic Buccal Ureteroplasty: a Review of the Current Literature

PURPOSE OF REVIEW

This study aimed to provide an overview of the literature on buccal mucosal ureteroplasty for ureteral stricture disease, with a specific focus on the application of the robotic platform to buccal ureteroplasty.

RECENT FINDINGS

In our review, we highlight the results of Zhao et al. from the New York University School of Medicine Department of Urology, as well as our own results from Temple University Hospital. Zhao et al. published the first series of four patients who underwent robotic buccal ureteroplasty. Mean stricture length was 3.0 cm, and at a mean follow-up of 15 months, all repairs remained patent. We also describe our results in 10 patients who underwent robotic buccal ureteroplasty at Temple University Hospital. Median stricture length was 3.0 cm, and at a median follow-up of 5 months, all repairs remain patent. Robotic buccal ureteroplasty offers a promising option for repair of complex ureteral strictures.

Ureteral Reconstruction With Ileum: Long-term Follow-up of Renal Function

OBJECTIVE

To assess long-term renal preservation and surgical outcomes in patients undergoing ureteric substitution with ileum. This has been a mainstay of reconstruction options for lengthy ureteral defects.

METHODS

Consecutive patients aged 18 or older undergoing ileal ureters at our institution were retrospectively reviewed (from 1989 to June 2013). Patients with <6 months of follow-up were excluded. Demographic, surgical, and renal functional outcomes were reviewed. Renal function was assessed by the Chronic Kidney Disease Epidemiology Collaboration and Modification of Diet in Renal Disease Study equations.

RESULTS

Of the 108 patients meeting the inclusion criteria, 86 (79.6%) had single-renal unit reconstruction and 22 had bilateral reconstruction. Eighty-four (77.8%) had radiation-induced stricture and 24 had iatrogenic or trauma-induced strictures. The median follow-up was 51 months (interquartile range: 22-112). Short-term complications included Clavien grade I (16 [14.8%]), Clavien grade II (3 [2.8%]), Clavien grade III (9 [8.3%]), and Clavien grade IV (3 [2.8%]). Long-term complications included fistula in 6 patients (5.6%), renal failure requiring dialysis in 2 patients (1.9%), hyperchloremic metabolic acidosis in 4 patients (3.7%), and incisional hernia in 11 patients (10.2%). Nine patients (8.3%) had small-bowel obstructions; 3 (2.8%) required adhesiolysis. Four patients (3.7%) had an anastamotic stricture. Nineteen patients (17.6%) had worsening renal function. Cox proportional hazards regression found that those with bilateral repair were at 3.7 times increased risk of worsening renal function (P = .02).

CONCLUSION

Ureteral substitution with ileum provides an effective and versatile long-term reconstructive option with minimal renal function compromise in properly selected patients. Bilateral reconstruction may contribute to worse long-term renal function.

Total proximal ureter substitution using buccal mucosa

The surgical treatment of a long proximal ureteral stricture is a challenging situation for reconstructive surgeons. Despite the underlying morbidities, ileal interposition and autotransplantation are the options available to treat complex cases of long segment ureteral stricture. Buccal mucosa has shown excellent results in urethroplasty. However, its use in ureteral reconstruction is infrequent. We report on a 64-year-old female patient with multiple comorbidities and prior abdominal surgeries for Crohn's disease who underwent a successful total substitution of a long segment of the proximal ureter using buccal mucosa. Regular postoperative isotope scans showed improvement in renal function. Based on the pleasant outcome of this case and review of the literature, buccal mucosa might be a viable option with low morbidity in selected cases.

A case report on buccal mucosa graft for upper ureteral stricture repair

Management of ureteric stricture especially long length upper one-third poses a challenging job for most urologists. With the successful use of buccal mucosa graft (BMG) for stricture urethra leads the foundation for its use in ureteric stricture also. A 35-year-old male diagnosedcase of left upper ureteric stricture, postureteroscopy with left percutaneous nephrostomy (PCN) in situ. Cysto-retrograde pyelography and nephrostogram done simultaneously suggestive of left upper ureteric stricture of 3 cm at L3 level. On exploration, diseased ureteral segment exposed, BMG harvested and sutured as onlay patch graft with supportive omental wrap. The treatment choice for upper ureteric long length stricture is inferior nephropexy, autotransplantation, or bowel interposition. With PCN in situ, inferior nephropexy becomes technically difficult, other two are morbid procedures. Use of BMG in this situation is technically better choice with all the advantages of buccal mucosa. Onlay BMG for ureteral stricture is technically easy, less morbid procedure and can be important choice in future.

Urothelial-based reconstructive surgery for upper- and mid-ureteral defects: Long-term results

INTRODUCTION

Ureteral strictures can result in obstructive nephropathy and renal function deterioration. Surgical management of ureteral defects, especially in the proximal- and mid-ureter, is particularly challenging. Our purpose was to analyze the long-term outcomes of urothelial-based reconstructive surgery for upper- and mid-ureteral defects.

METHODS

We conducted a retrospective analysis of a single tertiary centre's database, including 149 patients treated for ureteral defects between 2001 and 2011. Thirty-one patients (21%) underwent complex urothelial-based surgical repairs for upper- and mid-ureter defects. Patients' median age was 61 years. The mean length of the ureteral strictures was 2.5 cm, located in upper-, mid-ureter, or in between in 19 (61%), 10 (32%), and two (6%) patients, respectively. All patients were treated with a primary urothelial-based repair. Median followup time was 26 months. The primary outcome of the study was the long-term preservation of renal function and lack of clinical obstruction. The secondary endpoint of the study was the assessment of the intra- and postoperative complication rates.

RESULTS

Most of the lesions were benign (22, 71%), while nine strictures (29%) were malignant. Seven patients (23%) suffered from postoperative complications, five of which were infectious. The median pre- and postoperative calculated glomerular filtration rates were 66 ml/min/1.72m2 and 64ml/min/1.72m2, respectively. Success rate was 84%, defined as lack of need for re-operation or kidney drainage at the last followup.

CONCLUSIONS

Upper- and mid-ureteral defects present a complex pathology necessitating experienced reconstructive surgical skills. Our data suggest good long-term results for primary urothelial-based reconstructions for these pathologies.

Laparoscopic onlay lingual mucosal graft ureteroplasty for proximal ureteral stricture: initial experience and 9-month follow-up

PURPOSE

We present our initial experience and 9-month outcomes of the novel technique of laparoscopic onlay lingual mucosal graft ureteroplasty for proximal ureteral stricture.

MATERIALS AND METHODS

In June 2015, transperitoneal laparoscopic onlay lingual mucosal graft ureteroplasty was performed on a male patient with proximal stricture of the left ureter. The patient complained with left frank pain. Severe hydronephrosis and proximal ureteral dilatation were noted through ultrasonography and CT scan. The length of upper ureteral stricture was 30 mm including 10-mm occlusion. A 46 mm in length and 15 mm in width lingual mucosa graft was harvested from the ventral of the tongue and placed in the strictured ureter as a ventral onlay for laparoscopic ureteroplasty. Operative time, intraoperative, and postoperative complications were well recorded. Follow-up was performed with renal ultrasound, CT scan, and nuclear scan renography as well as clinical assessment of symptoms.

RESULTS

The new technique was performed successful without intraoperative and postoperative complications. Neither hydronephrosis nor proximal ureteral dilatation in the left side was found through ultrasonography 3, 6, 9 months and CT scan 6 month postoperatively. The left renal function, glomerular filtration rate, had a recovery from 9.6 ml/min preoperatively to 14.0 ml/min at 6-month follow-up, and the patient has no complaints about the donor site and flank pain.

CONCLUSIONS

To our knowledge, we present the initial experience with laparoscopic onlay lingual mucosal graft ureteroplasty for proximal ureteral stricture. With 9-month outcomes, the new technique appears to be an excellent option for proximal ureteral stricture.

Long ureteric stricture replacement by buccal mucosa graft: an Armenian experience case series report

Introduction

The aim of this study is to demonstrate the results of a case series concerning the replacement of long ureteric strictures using buccal mucosa grafts.

Material and methods

Five patients (3 men, 2 women), with a mean age of 35 years old, underwent reconstructive ureteral surgery using buccal mucosa graft with omental wrapping during the period of 2010–2013. In all cases, the location of strictures was in the proximal ureters with the length of strictures varying from 2.5 to 5.0 cm.

Results

We did not observe any major complications postoperatively. Two patients complained of constipation, which was resolved on the second day without any special treatment. Only one patient experienced fever (39°C) on the seventh day after the surgery due to inadequate drainage of the nephrostomic tube. Mean follow-up time was 39.6 months (range 26–52 months), mean hospital stay length was 10.6 days. Intravenous and antegrade urography were performed after removing JJ stents. Results were favorable without any signs of stricture. Repetitive ultrasound and radiologic imaging was performed at month 3, 6, 12 in the first year and every half-year thereafter. Intravenous urography showed no signs of strictures. Hydronephrosis was resolved in all patients by the sixth month following the surgery.

Conclusions

Postoperatively, we observed favorable results in all patients in terms of absence of short term-surgical complications. This technique could be considered for patients with long ureteric strictures in whom ureteral replacement with bowel interposition or kidney auto-transplantation is contraindicated.

Tissue transfer techniques in reconstructive urology

Tissue transfer techniques are an essential part of the reconstructive urologist's armamentarium. Flaps and graft techniques are widely used in genital and urethral reconstruction. A graft is tissue that is moved from a donor site to a recipient site without its native blood supply. The main types of grafts used in urology are full thickness grafts, split thickness skin grafts and buccal mucosa grafts. Flaps are transferred from the donor site to the recipient site on a pedicle containing its native blood supply. Flaps can be classified based on blood supply, elevation methods or the method of transfer. The most used flaps in urology include penile, preputial, and scrotal skin. We review the various techniques used in reconstructive urology and the outcomes of these techniques.

Outcomes of robotic-assisted laparoscopic upper urinary tract reconstruction: 250 consecutive patients

OBJECTIVE

To evaluate the long-term outcomes of robotic-assisted laparoscopic (RAL) upper urinary tract (UUT) reconstruction performed at a tertiary referral centre.

MATERIALS AND METHODS

Data from 250 consecutive patients undergoing RAL UUT reconstruction, including pyeloplasty with or without stone extraction, ureterolysis, uretero-ureterostomy, ureterocalicostomy, ureteropyelostomy, ureteric reimplantation and buccal mucosa graft ureteroplasty, were collected at a tertiary referral centre between March 2003 and December 2013. The primary outcomes were symptomatic and radiographic improvement of obstruction and complication rate. The mean follow-up was 17.1 months.

RESULTS

Radiographic and symptomatic success rates ranged from 85% to 100% for each procedure, with a 98% radiographic success rate and 97% symptomatic success rate for the entire series. There were a total of 34 complications, none greater than Clavien grade 3.

CONCLUSION

Robotic-assisted laparoscopic UUT can be performed with few complications, with durable long-term success, and is a reasonable alternative to the open procedure in experienced robotic surgeons.

Ureteral strictures revisited…trying to see the light at the end of the tunnel: a comprehensive review

A ureteral stricture is a rather rare urological event defined as a narrowing of the ureter causing a functional obstruction and renal failure, if left untreated. The aim of this review article is to summarize and discuss current knowledge on the incidence, pathogenesis, management, and follow up of proximal, mid, and distal ureteral strictures.

[Avoidance and management of complications in open surgical ureter reconstruction]

Open surgical reconstruction of the ureter is a urological procedure with a potentially high risk of complications. The correct selection of patients and time of operation are important aspects regarding the treatment strategy. Position and length of the affected ureter segment to be reconstructed determine the surgical intervention possibilities. The psoas hitch procedure is a well-established technique for distal reconstruction of the ureter where most iatrogenic injuries occur. In more proximal or complex defects, several procedures are available. Partial or complete replacement of the ureter with bowel is still considered the standard for bridging long ureteral defects but is accompanied with higher intra- and postoperative complication rates. In specific patients and situations, autotransplantation of the kidney and subcutaneous pyelovesical bypasses are clinical options. Using mucosal grafts or tissue engineering may be new therapeutic prospects to cover ureteral defects but the clinical impact still needs to be clarified. All therapeutic strategies share the fact that great surgical expertise and experience are necessary as the operative technique must be mastered to avoid severe complications.

Pseudospongioplasty using periurethral vascularized tissue to support ventral buccal mucosa grafts in the distal urethra

PURPOSE

For ventral buccal mucosa graft onlay during bulbar urethroplasty, spongioplasty with advancement and closure of the corpus spongiosum is ordinarily performed to stabilize the graft. In the pendulous and distal bulbar urethra the spongiosum is often too thin to allow complete graft coverage. We describe the results of what to our knowledge is a novel technique for ventral graft coverage using periurethral vascularized tissue. We compared these results to those of conventional spongioplasty.

MATERIALS AND METHODS

We retrospectively reviewed all urethroplasties performed by 2 surgeons at separate tertiary care facilities from July 2007 to July 2012. One-stage urethroplasties involving ventral buccal mucosa graft placement were selected for analysis. Conventional spongioplasty was performed when possible. When spongiosal tissue was inadequate for graft coverage, periurethral tissue flaps were mobilized bilaterally and sutured together in the midline as pseudospongioplasty to provide coverage. We compared the outcomes of the 2 techniques.

RESULTS

Of 637 urethroplasties performed during the 5-year study period 102 (16%) with a buccal mucosa graft onlay met study inclusion criteria. Pseudospongioplasty was performed in 46 of 102 cases (45%), predominantly in the pendulous urethra (34 of 46 or 74%), with success in 37 of 46 (80%) at a mean followup of 41 months. Conventional spongioplasty had a similar 84% success rate (47 of 56 cases) at a mean followup of 39 months (p = 0.645). For conventional spongioplasty mean stricture length was 4.7 cm compared to 5.8 cm for pseudospongioplasty (p = 0.028).

CONCLUSIONS

Ventral buccal mucosa grafts can be applied reliably to various locations throughout the anterior urethra. For distal grafts, flaps of periurethral tissue provide a suitable host bed for revascularization with results equivalent to those of conventional spongioplasty.

Strategies for open reconstruction of upper ureteral strictures

This article presents a review of the literature regarding surgical techniques and outcomes for reconstruction of strictures involving the upper ureter. The preoperative assessment for proximal ureteral stricture is briefly reviewed, followed by a discussion of ureteroureterostomy, transureteroureterostomy, ureterocalicostomy, bladder flaps, downward nephropexy, bowel interposition grafts, onlay or tubular grafting, renal autotransplantation, and nephrectomy. The future direction for reconstruction of the proximal ureter is proposed.

Tissue engineering and ureter regeneration: is it possible?

Large ureter damages are difficult to reconstruct. Current techniques are complicated, difficult to perform, and often associated with failures. The ureter has never been regenerated thus far. Therefore the use of tissue engineering techniques for ureter reconstruction and regeneration seems to be a promising way to resolve these problems. For proper ureter regeneration the following problems must be considered: the physiological aspects of the tissue, the type and shape of the scaffold, the type of cells, and the specific environment (urine). 
This review presents tissue engineering achievements in the field of ureter regeneration focusing on the scaffold, the cells, and ureter healing.