Augmented Anastomotic Ureteroureterostomy
Augmented anastomotic ureteroplasty is a hybrid ureteral reconstruction that combines primary ureteral reanastomosis on one wall with oral mucosal graft or pedicled flap augmentation on the opposite wall. It is also called augmented anastomotic ureteroureterostomy because the operation borrows the logic of end-to-end ureteroureterostomy but avoids the circumferential tension that would occur if the entire stricture were excised and rejoined.[1][2][3]
This page covers the hybrid transecting/graft-augmented configuration. For short-segment primary repair, see Ureteroureterostomy. For non-transecting graft onlay, see Buccal Mucosa Graft Onlay (Ureter). For long-segment substitution, see Ileal Ureter Substitution.
Concept
Standard ureteroureterostomy is limited by gap length after debridement. Once the diseased segment exceeds roughly 2-3 cm, complete excision and end-to-end repair can become ischemic or tight. Pure oral mucosa onlay works best when the lumen remains patent enough to open longitudinally without transecting the ureter. Augmented anastomotic ureteroplasty sits between those two operations.[1][2][4]
The core maneuver:
- excise the most obliterated or worst-scarred portion of the stricture,
- reapproximate healthy ureter on one wall, usually posterior or dorsal,
- bridge the remaining defect on the opposite wall with buccal mucosa, lingual mucosa, or a vascularized appendiceal flap,
- wrap or support the repair with omentum when possible.
This converts a longer partially obliterated stricture into a shorter primary anastomosis plus a patch-augmented lumen. In contemporary robotic series and reconstructive reviews, this strategy is used for strictures that are commonly about 2-8 cm, avoiding bowel substitution or renal autotransplantation in appropriately selected patients.[1][2][6][11]
Indications
Augmented anastomotic ureteroplasty is best for complex proximal or mid-ureteral strictures that are too long for primary ureteroureterostomy but too focal for bowel interposition.[1][2][5][12]
| Indication | Why the Hybrid Repair Fits |
|---|---|
| Long proximal or mid-ureteral stricture, usually 2-8 cm | Primary UU would be tight; onlay alone may not address an obliterated segment |
| Partially obliterated stricture | The obliterated segment is excised, while the remaining narrowed segment is graft-augmented |
| Failed pyeloplasty or failed endoscopic management | Avoids repeatedly incising dense scar while preserving native ureter |
| Periureteral fibrosis limiting mobilization | Reduces the amount of ureter that must be excised and mobilized |
| Stricture too short for ileal ureter or autotransplantation | Provides a tissue-sparing option before major substitution |
| Right-sided stricture with usable appendix | Allows appendiceal onlay or interposition in selected anatomy[7][10] |
It is not the default for simple short strictures. If the ureter reaches without tension after debridement, standard ureteroureterostomy remains simpler. If the stricture is pan-ureteral, ischemic over a long segment, or embedded in hostile tissue without a graft bed, ileal ureter, transureteroureterostomy, renal autotransplantation, or nephrectomy may be more realistic.
Preoperative Planning
Preoperative planning should define length, location, renal salvageability, and graft strategy.
| Question | Planning Tool |
|---|---|
| Where are the proximal and distal limits? | CT urogram, MR urogram, antegrade/retrograde pyelography |
| Is the segment obliterated or merely narrowed? | Retrograde pyelogram, antegrade study, diagnostic ureteroscopy |
| Is the kidney worth reconstructing? | MAG3/DTPA renography, serum creatinine, cortical thickness, symptoms |
| Is the oral cavity suitable? | Prior graft harvest history, oral disease, mouth opening, patient preference |
| Is an omental wrap available? | Prior abdominal surgery, side of repair, transperitoneal access |
| Is appendix an option? | Right-sided stricture, healthy appendix, adequate length and mesentery |
Concurrent intraoperative ureteroscopy can help identify the distal extent of a stricture, guide dissection by transillumination, and confirm that the distal lumen is healthy enough to accept reconstruction.[8] Fluorescence guidance with indocyanine green (ICG) may help define ureteral blood supply and anatomy in robotic reconstructions, though it does not replace judgment about tissue quality.
Operative Strategy
Most contemporary reports are robotic, but the same reconstruction can be performed open or laparoscopically in experienced hands.[1][2][6]
Exposure and stricture definition
- Expose the ureter transperitoneally or retroperitoneally depending on location and prior surgery.
- Preserve periureteral adventitia and blood supply wherever possible.
- Identify the stricture by visual inspection, ureteroscopy, stent palpation, fluorescence, and/or ureterotomy.
- Mobilize only enough ureter for a tension-free posterior anastomosis.
Excision of the obliterated segment
The most severely diseased portion is excised. The goal is not to remove the entire strictured length; it is to remove the non-reconstructable core while preserving narrowed but viable ureter for graft augmentation.[2][3]
Principles:
- debride to bleeding, viable mucosa,
- avoid stripping the remaining ureteral plate,
- keep the residual defect short enough for a stable graft bed,
- confirm the proximal and distal lumens pass a guidewire or stent.
Primary wall anastomosis
The posterior or dorsal ureteral wall is reapproximated end-to-end with interrupted or running absorbable sutures, usually 4-0 or 5-0. This recreates one side of the ureter from native ureteral tissue and shortens the remaining defect.[2][3]
The posteriorly augmented lingual mucosa technique emphasizes this sequence: first anastomose the posterior ureteral wall, then leave the ventral defect open for graft onlay.[3]
Graft harvest
| Graft | Role | Practical Notes |
|---|---|---|
| Buccal mucosa graft | Most established free graft | Robust lamina propria, familiar urethroplasty harvest, usually enough length for 6-8 cm repairs[1][5] |
| Lingual mucosa graft | Alternative oral mucosa graft | Useful when buccal harvest is undesirable or exhausted; reported with low oral morbidity and strong early/mid-term outcomes[2][3][6] |
| Appendiceal flap | Vascularized right-sided option | Pedicled tissue avoids free-graft take dependency, but requires healthy appendix, favorable mesentery, and right-sided reach[7][10] |
For free oral mucosa grafts, the graft is defatted and tailored to be slightly longer and wider than the ureteral defect. The epithelial surface faces the lumen.
Ventral or anterior onlay
The graft is sutured to the ureteral edges to complete the circumference. The repair should be wide, watertight, and not strangulated. A double-J stent is placed across the reconstruction before closure is completed.[1][2][5]
Technical rules:
- use a broad graft; do not create a narrow patch,
- keep the graft flat and untwisted,
- avoid tension at both graft apices,
- make the native posterior anastomosis carry alignment, not tension,
- ensure the stent crosses both ends of the repair.
Omental wrap and drainage
Omentum is commonly wrapped around the reconstructed segment to provide vascular support and physical coverage. In the lingual mucosa 41-case series, omental wrap was used in 90% of patients; in robotic BMG series, omental support is also a routine technical principle.[1][2]
Drain placement and Foley duration depend on leak risk, operative field, and institutional practice. Stent removal is commonly performed around 6 weeks to 3 months, with longer dwell times in tenuous repairs.[2][3]
Augmented Anastomotic vs Non-Transecting Onlay
| Feature | Augmented Anastomotic | Non-Transecting Onlay |
|---|---|---|
| Best stricture | Partially obliterated or mixed obliterated+narrowed stricture | Narrowed but patent lumen |
| Ureteral transection | Yes, at the obliterated segment | No, ureter is opened longitudinally |
| Native ureter repair | One wall is reanastomosed end-to-end | Native ureteral plate remains continuous |
| Graft role | Completes the opposite wall and augments circumference | Widens the incised strictured lumen |
| Main advantage | Handles an obliterated core while avoiding full substitution | Maximizes blood supply by avoiding transection |
| Main risk | Transection can jeopardize blood supply if overdone | Inadequate if lumen is obliterated or scar plate is poor |
In the 10-year multi-institutional robotic BMG cohort, no significant success difference was found between onlay and augmented anastomotic techniques, and anastomotic technique was not an independent predictor of failure.[4]
Outcomes
| Series | Technique Mix | Key Outcomes |
|---|---|---|
| Zhao et al. 2018 | 19 robotic BMG ureteroplasties; onlay 79%, augmented anastomotic 21% | 90% success at median 26 months[1] |
| Lee et al. 2021 | 54 robotic BMG ureteroplasties | 87.0% success at median 27.5 months; major complications 5.6%; median length of stay 1 day[5] |
| Liang et al. 2022 | 41 robotic LMG ureteroplasties; augmented anastomotic 41%, onlay 59% | 97.6% success at median 35 months; omental wrap in 90%[2] |
| Fan et al. 2021 | 10 posteriorly augmented anastomotic LMG ureteroplasties | 100% success at median 11 months; median residual defect 3 cm and graft length 4 cm[3] |
| Chao et al. 2025 | 163 robotic BMG ureteroplasties over 10 years | 92.0% success at median 29 months; median time to failure 10.2 months; technique not an independent failure predictor[4] |
| Wang et al. 2026 | 15 robot-assisted LMG reconstructions; augmented anastomotic 47%, onlay 53% | 87% success at median 21 months; estimated 2-year recurrence-free survival 83%[6] |
Systematic evidence supports the broader oral mucosal graft ureteroplasty concept. A BMG ureteroplasty systematic review of 72 procedures reported 91.6% overall success and 5% Clavien-Dindo grade 3 or higher complications.[13] A 2023 meta-analysis comparing oral mucosal graft ureteroplasty with ileal ureter replacement found pooled success of 94.9% for oral mucosal graft ureteroplasty versus 85.8% for ileal ureter, with lower low-grade, high-grade, and long-term complication rates in the graft group.[12]
Complications
| Complication | Notes |
|---|---|
| Stricture recurrence | Main failure mode; in the 163-patient BMG cohort, median time to failure was 10.2 months[4] |
| Early obstruction after stent removal | Can reflect edema, leak, collection, or technical narrowing |
| Urinary leak or urinoma | Usually managed with drainage, stent duration, or percutaneous intervention |
| UTI or pyelonephritis | Common low-grade complication across ureteral reconstruction series |
| Clavien-Dindo grade 3 or higher complication | About 5-5.6% in BMG systematic review and updated multi-institutional BMG series[5][13] |
| Oral donor-site morbidity | Pain, numbness, tightness, bleeding, or lingual hypoesthesia; usually transient, but donor-site bleeding can require intervention[6][9] |
Failure after oral mucosa ureteroplasty may still be salvageable with repeat grafting, ileal ureter, renal autotransplantation, chronic stenting, nephrostomy, or nephrectomy depending on renal function and stricture biology.
Advantages
- Extends the reconstructable range beyond simple ureteroureterostomy.
- Avoids bowel harvest, mucus, metabolic acidosis, chronic bacteriuria, and long-term bowel-substitution complications.
- Avoids renal autotransplantation in many focal proximal/mid-ureteral strictures.
- Preserves native ureteral tissue and at least one native ureteral wall.
- Fits robotic reconstruction well because the operation is suture-intensive rather than bowel-intensive.
- Provides outcomes comparable to pure onlay configurations in current series.[4][12]
Limitations
- Requires a viable graft bed and adequate periureteral vascularity.
- Usually not appropriate for strictures longer than about 8 cm with current unilateral oral graft practice.[6][12]
- Evidence is retrospective and mostly from high-volume reconstructive centers.
- Long-term durability beyond 5 years remains less mature than ileal ureter or classic reimplantation data.
- Oral graft harvest adds donor-site morbidity and requires patient counseling.
- Appendiceal flap options are right-sided and anatomy-dependent.[7][10]
Operative Pearls
- Do not turn a fully patent stricture into a transected repair unless the obliterated segment demands it.
- The native posterior wall anastomosis should align the ureter; the graft should augment, not rescue tension.
- Measure the defect after debridement and after the posterior wall is reapproximated.
- Harvest a graft slightly longer than the final defect; short grafts create narrow apices.
- Omentum is not decorative here; it is part of the graft-take strategy.
- A right-sided appendix may be better than oral mucosa when it reaches easily with a healthy mesentery.
- If the stricture is long, ischemic, radiated, and poorly vascularized, bowel or autotransplant may be the cleaner operation.
References
1. Zhao LC, Weinberg AC, Lee Z, et al. Robotic ureteral reconstruction using buccal mucosa grafts: a multi-institutional experience. Eur Urol. 2018;73(3):419-426. doi:10.1016/j.eururo.2017.11.015.
2. Liang C, Wang J, Hai B, et al. Lingual mucosal graft ureteroplasty for long proximal ureteral stricture: 6 years of experience with 41 cases. Eur Urol. 2022;82(2):193-200. doi:10.1016/j.eururo.2022.05.006.
3. Fan S, Yin L, Yang K, et al. Posteriorly augmented anastomotic ureteroplasty with lingual mucosal onlay grafts for long proximal ureteral strictures: 10 cases of experience. J Endourol. 2021;35(2):192-199. doi:10.1089/end.2020.0686.
4. Chao BW, Raver M, Lin JS, et al. Robotic buccal mucosa graft ureteroplasty: a decade of experience from a multi-institutional cohort. Urology. 2025;197:174-179. doi:10.1016/j.urology.2024.11.059.
5. Lee Z, Lee M, Koster H, et al. A multi-institutional experience with robotic ureteroplasty with buccal mucosa graft: an updated analysis of intermediate-term outcomes. Urology. 2021;147:306-310. doi:10.1016/j.urology.2020.08.003.
6. Wang Z, Plamadeala N, Ogalla A, Tailly T, Verla W, Lumen N. Robot-assisted lingual mucosa graft onlay reconstruction for ureteric strictures refractory to endoscopic treatment. J Vis Exp. 2026;(228). doi:10.3791/68627.
7. Gabrielson A, Li O, Cohen AJ. Robotic-assisted augmented roof ureteroplasty with appendiceal onlay flap. Urology. 2023;176:243-245. doi:10.1016/j.urology.2023.02.027.
8. Arora S, Campbell L, Tourojman M, et al. Robotic buccal mucosal graft ureteroplasty for complex ureteral stricture. Urology. 2017;110:257-258. doi:10.1016/j.urology.2017.06.037.
9. Xiong S, Wang J, Zhu W, et al. Onlay repair technique for the management of ureteral strictures: a comprehensive review. Biomed Res Int. 2020;2020:6178286. doi:10.1155/2020/6178286.
10. Zhang B, Chen J, Chen X, et al. Laparoscopic ureteroplasty for the treatment of long ureteral strictures with appendiceal interposition and appendiceal onlay flap: technical description and initial experience. World J Urol. 2025;43(1):678. doi:10.1007/s00345-025-06048-8.
11. Bello D, Van Shufflin M, Hofer MD. Expanding the armamentarium: perspectives on buccal mucosal grafts and appendiceal flaps in ureteral reconstructive surgery. J Clin Med. 2025;14(21):7681. doi:10.3390/jcm14217681.
12. You Y, Gao X, Chai S, et al. Oral mucosal graft ureteroplasty versus ileal ureteric replacement: a meta-analysis. BJU Int. 2023;132(2):122-131. doi:10.1111/bju.15994.
13. Heijkoop B, Kahokehr AA. Buccal mucosal ureteroplasty for the management of ureteric strictures: a systematic review of the literature. Int J Urol. 2021;28(2):189-195. doi:10.1111/iju.14426.