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Ureteral Stricture

Ureteral stricture disease is pathologic narrowing of the ureteral lumen that obstructs urine flow and threatens the renal unit. Modern stricture disease is predominantly iatrogenic and stone-related rather than congenital, and the operative algorithm is dictated by four variables: location, length, etiology, and the integrity of the surrounding vascular bed.[1][2][3] Reconstruction is the durable treatment — endoscopic options remain reasonable for a narrow set of short, well-vascularized strictures but carry substantially higher long-term failure rates.[1]

For congenital ureteropelvic-junction obstruction — the dominant proximal-stricture etiology in pediatrics and the most common primary indication for pyeloplasty — see UPJ Obstruction. This article focuses on acquired ureteral strictures of the upper, mid, and distal ureter.

Etiology and Epidemiology​

Acquired benign ureteral strictures are dominated by stone disease and iatrogenic injury, with stone-related etiologies accounting for ~85% of cases in modern series.[1]

CategoryMechanismNotes
Stone-relatedImpacted stone, stone granuloma, mucosal injury during ureteroscopyStricture rate ~2.9% after URS overall; up to 24% after URS for impacted stones[2][9]
Iatrogenic — gynecologicHysterectomy, cesarean section, endometriosis surgery, prolapse repairLaparoscopic hysterectomy carries ~2× the ureteral injury risk vs open (OR 2.12)[5][6][7]
Iatrogenic — colorectalLAR, APR, sigmoidectomyRetroperitoneal dissection near the pelvic brim and sacral promontory
Iatrogenic — urologicPyeloplasty, ureteral reimplant, prior endoscopic surgery
Post-transplantIschemia at the ureterovesical anastomosis, BK virus, rejectionIncidence 1.4–10%; 81% at the UVJ[30][31]
RadiationCervical, prostate, rectal cancer treatmentLong, ischemic, often progressive; poor candidates for endoscopic repair
Inflammatory / infiltrativeRetroperitoneal fibrosis, tuberculosis, endometriosis
IdiopathicNo identifiable causeDiagnosis of exclusion

Iatrogenic ureteral injury — the operative reality the reconstructive surgeon manages:[5][6][7][8]

  • Ureteral injury complicates ~0.08% of gynecologic laparoscopy for benign indications
  • 62% of injuries during hysterectomy are unrecognized intraoperatively, and missed injury drives the morbidity: adjusted odds ratio for urinary fistula 124 (vs 5.9 with intraoperative recognition), sepsis 11.9 (vs 2.0), and acute renal failure 23.8
  • Intraoperative recognition collapses complication management failure (OR 0.22)
  • Prophylactic ureteral stenting in high-risk gynecologic cases reduces injury risk modestly (OR 0.61, NNT 224)

These data are the case for early consult, intraoperative ureteral identification, and a low threshold for direct repair when called to the table — covered operatively under Intraoperative Consultation.

Pathophysiology​

Stricture formation follows a stereotyped inflammation → fibroproliferation → collagen deposition cascade after mucosal, thermal, ischemic, or mechanical insult.[4] Histologic series classify benign strictures into three overlapping patterns: inflammatory cell infiltration (~32%), fibroplasia (~45%), and hyalinization (~23%), with progressive type I and III collagen deposition as the lesion matures.[4]

Two practical points for the reconstructive surgeon:

  • Vascular supply determines the operation. Strictures with intact periureteral blood supply tolerate dilation or incision; ischemic strictures (radiation, devascularization at hysterectomy, prolonged stenting) do not — endoscopic success drops from ~89% to 17–40% when the bed is compromised.[12]
  • Indwelling stents are not benign. Stents themselves drive urothelial-mesenchymal transition and submucosal fibrosis, with histologic changes that persist after removal — relevant when planning long-term diversion vs definitive repair.[10]

Risk factors for post-ureteroscopy stricture:[2][9] ureteral perforation (strongest predictor), impacted stone, large stone burden, embedded fragments, failed initial URS, preoperative hydronephrosis, prior ureteral intervention.

Clinical Presentation​

Acquired ureteral strictures present with flank pain, recurrent UTI, hydronephrosis on imaging, hematuria, or asymptomatic renal-function decline. As with UPJO, the failure mode is often silent: a strictured upper tract can lose function for months before producing symptoms — a strong argument for surveillance imaging after at-risk pelvic surgery, ureteroscopy for impacted stones, and pelvic radiation.[1][2]

Diagnostic Evaluation​

The reconstructive workup answers four questions: Where is it? How long? What's the function? Is the bed vascularized?

ModalityRoleNotes
Renal ultrasoundInitial detection / serial surveillanceQuantifies hydronephrosis only
CT urographyAnatomic workhorse in adultsIdentifies stone, mass, periureteral pathology, level of obstruction
MR urographyPreferred when renal function is compromised or contrast contraindicated89% sensitivity for non-calculous obstruction in renal insufficiency vs 40% for non-contrast CT[11]
Retrograde pyelogramDefines stricture length, location, and the proximal/distal ureteral caliberUsually performed at the time of stent or definitive repair
Antegrade nephrostogramWhen retrograde access fails or a nephrostomy is already in placePairs naturally with antegrade endoureterotomy
Diuretic renography (MAG3)Quantifies split function and confirms true obstructionSame interpretive thresholds as in UPJO

The single most operative-decision-relevant finding from imaging is stricture length, which separates the small population that may benefit from endoscopic management (≤ 2 cm) from the large population that needs reconstruction.[1][12]

Management​

Principles​

  • Reconstruction is the gold standard — pooled success ~96% for definitive reconstruction vs ~52% long-term for endoscopic management.[1]
  • Endoscopic management is reasonable as first-line therapy only for short (≤ 2 cm), recent (<3 months), well-vascularized strictures with mild-to-moderate hydronephrosis.[1][12][13]
  • The surgical principles are unchanged across all reconstructions: tension-free, watertight, well-vascularized, spatulated, stented.[15]
  • Most recurrences after endoscopic treatment occur within 12 months, but late failures continue past 4 years — surveillance is mandatory.[28]

Endoscopic Management​

TechniquePooled successBest candidateCaveats
Balloon dilationTechnical 89%; long-term ~54%Short (≤ 2 cm), recent, intact vascular supplyDrops to 17–40% if vascular supply compromised[12][13]
Endoureterotomy (laser, cold knife, electrocautery)~85% short-termShort benign stricture; antegrade preferred for upper-tract, retrograde for distalInferior to reconstruction for long or ischemic strictures[3]
Self-expanding metallic stents (Allium, Memokath)90–92% at 1 yrShort strictures, post-transplant, frail / non-operative patientsMigration, encrustation, tissue ingrowth; not durable beyond 2–3 years[14]

Reconstruction by Location​

The choice of reconstruction follows the level of the stricture and the length of the defect.

Stricture locationShort (≤ 2–3 cm)Mid (3–8 cm)Long (> 8 cm) or panureteral
DistalUreteroneocystostomyPsoas hitch ± reimplantBoari flap ± psoas hitch
MidUreteroureterostomyBMG ureteroplastyBoari flap + psoas hitch (reach midureter); ileal ureter
ProximalUreteroureterostomyBMG ureteroplasty; ureterocalicostomy if intrarenal pelvisIleal ureter; renal autotransplantation
Panureteral——Ileal ureter (workhorse); renal autotransplantation (salvage)

Robotic platforms have largely supplanted laparoscopic and open approaches for elective ureteral reconstruction, with multi-institutional series reporting equivalent or superior outcomes and shorter length of stay across reimplant, psoas hitch, Boari, BMG ureteroplasty, ileal ureter, and even autotransplantation.[3][16][17]

Distal Reconstruction — Reimplant, Psoas Hitch, Boari Flap​

A graded set of operations on the bladder, deployed by length of distal defect:[15]

  1. Ureteroneocystostomy (refluxing or anti-refluxing) — the workhorse for the truly distal stricture. Success 91–98%. Anti-reflux technique (extravesical Lich-Gregoir or intravesical Cohen / Politano-Leadbetter) is preferred when the bladder is not high-pressure.
  2. Psoas hitch — for defects that prevent tension-free reimplant. The bladder is mobilized contralaterally, fixed to the ipsilateral psoas tendon (caudal to the genitofemoral nerve to spare it), and the ureter implanted into the cephalad bladder dome. Success up to 97%.
  3. Boari flap — for defects of 8–12 cm. A wide-based, anteriorly oriented bladder flap is tubularized over a stent and rotated cephalad to bridge the gap; combined with a psoas hitch when even more length is needed.

Mid-Ureteral Reconstruction​

  • Ureteroureterostomy — short defects (≤ 2–3 cm) with mobile, healthy ureter. Spatulated end-to-end anastomosis over a stent. Excellent results when tension-free.[16][17]
  • Buccal mucosa graft (BMG) ureteroplasty — see below.
  • Transureteroureterostomy — historically used for irreplaceable distal segments; rarely employed today given the durability of BMG and ileal ureter and the morbidity of jeopardizing the contralateral renal unit.

Buccal Mucosa Graft Ureteroplasty​

The most important technical advance in ureteral reconstruction of the past decade. BMG provides a vascularized, hardy, wet-environment-tolerant patch material that avoids the morbidity of bowel harvest and works at any level of the ureter.[18][19][20]

Technique:

  • Approach: robotic, transperitoneal, with the stricture exposed by mobilizing the ureter on its periureteral fat
  • Configuration: onlay graft (~79%) — anterior longitudinal stricturotomy with the graft sutured as a roof — or augmented anastomotic repair when the back wall is also diseased
  • Vascular cover: omental wrap in ~95% — the graft requires neovascularization from the surrounding bed, and omentum is the reliable bed
  • Stent for 4–6 weeks, retrograde pyelogram or MAG3 at stent removal

Outcomes:

  • Multi-institutional 10-year cohort (163 patients): 92.0% success at median 29 months[21]
  • Earlier series report 87–90% at median follow-up 26–28 months[19][20]
  • Effective in redo cases — 33–47% of patients in published series had failed prior reconstruction[20][21]
  • Median LOS 1–2 days for the robotic approach

Appendiceal flap ureteroplasty is a useful right-sided alternative when a normal appendix is in the field — used as an onlay or interposition; spares both bowel and oral mucosa.[20]

Ileal Ureter Substitution​

Reserved for panureteral or long-segment (> 12 cm) defects where local options fail — extensive radiation injury, multiple failed prior reconstructions, recurrent strictures from systemic disease.[22][23]

  • Technique: isolated ileal segment (12–15 cm typical), isoperistaltic orientation, proximal anastomosis to renal pelvis or proximal ureter, distal anastomosis to bladder
  • Antireflux maneuvers: iliopsoas tunnel technique (extramural ileal segment buried in psoas) reduces reflux-related complications[24]
  • Combined techniques for full-length defects: ileal segment plus Boari flap and psoas hitch to extend bladder reach[23]
  • Success ~83% at mean 4.4 years follow-up[22]
  • Morbidity unique to ileum: mucus production (chronic intermittent obstruction), hyperchloremic metabolic acidosis (especially with poor function or short ileum), B12 deficiency over years, bowel-anastomosis morbidity. Contraindications include CKD with serum creatinine > 2 mg/dL (acidosis risk), inflammatory bowel disease, prior pelvic radiation involving the bowel.

Renal Autotransplantation​

Salvage operation for the most extensive reconstructive failures — total ureteral loss after multiple prior attempts, panureteral radiation injury where ileum is unavailable, or extensive periureteral malignancy precluding orthotopic reconstruction.[25][27]

  • Long-term graft function > 90% at median > 6 years follow-up[27]
  • Graft loss ~5–10%; cold ischemia time is the dominant predictor of complications
  • Modern series increasingly report robotic kidney autotransplantation (RAKAT) with comparable function, similar high-grade complication rates, and shorter recovery vs robotic ileal ureter (RAIUR) — choice driven by patient anatomy, prior surgery, and surgeon experience[26]

Post-Transplant Ureteral Strictures​

Stricture in a transplanted ureter is a distinct problem because the ureter is short, end-arterial, and the recipient has comorbid CKD that limits diagnostic and operative tolerance.[29][30][31]

  • Incidence 1.4–10%
  • Most strictures arise at the ureterovesical anastomosis (~81%), reflecting the watershed blood supply of the distal transplant ureter
  • Etiology: ischemia (dominant), technical, BK virus reactivation, acute or chronic rejection
  • Endoscopic management (balloon dilation, metallic stents): reasonable for short, early strictures; Allium-stent series report ~90% intermediate-term success[29]
  • Definitive reconstruction — pyeloureterostomy to native ureter, transplant-to-native ureteroureterostomy, or redo ureteroneocystostomy with a Boari flap — yields 87–93% success and is preferred over chronic stenting, which is associated with progressive eGFR decline[30]
  • Robotic transplant-ureter reconstruction — including single-port platforms — is feasible and durable, with multi-institutional success ~93% and median 3-day LOS[31][32]

Prevention​

The majority of acquired ureteral strictures are preventable — the operative window is in the original case, not at the reconstruction.[5][8][33]

  • Ureteroscopy: avoid perforation, minimize mucosal trauma at impacted stones, size the access sheath to the ureter, stent any procedure with intraoperative concern
  • Pelvic surgery: anatomic identification of the ureter at the pelvic brim and along the cardinal ligament; selective prophylactic stenting in high-risk gynecologic cases
  • Intraoperative recognition of injury is the single most important determinant of long-term outcome — when in doubt, retrograde study or direct inspection on the table
  • Indocyanine green (ICG) fluorescence is increasingly used at the time of reconstruction to confirm ureteral perfusion and define healthy margins for resection

For the acute consult on a recognized intraoperative ureteral injury, see Intraoperative Consultation.

References​

1. Ou Y, Zhang G, Zhu X, et al. "Evaluation of risk factors, treatment options, and prognostic-related factors in patients with benign ureteral strictures: an 8-year single-center experience." Int J Urol. 2023;30(10):847–852. doi:10.1111/iju.15211

2. Sunaryo PL, May PC, Holt SK, et al. "Ureteral strictures following ureteroscopy for kidney stone disease: a population-based assessment." J Urol. 2022;208(6):1268–1275. doi:10.1097/JU.0000000000002929

3. Drain A, Jun MS, Zhao LC. "Robotic ureteral reconstruction." Urol Clin North Am. 2021;48(1):91–101. doi:10.1016/j.ucl.2020.09.001

4. Tan J, Yu Z, Ling X, et al. "Main pathological changes of benign ureteral strictures." Front Med. 2022;9:916145. doi:10.3389/fmed.2022.916145

5. Yanagisawa T, Mori K, Quhal F, et al. "Iatrogenic ureteric injury during abdominal or pelvic surgery: a meta-analysis." BJU Int. 2023;131(5):540–552. doi:10.1111/bju.15913

6. Wong JMK, Bortoletto P, Tolentino J, Jung MJ, Milad MP. "Urinary tract injury in gynecologic laparoscopy for benign indication: a systematic review." Obstet Gynecol. 2018;131(1):100–108. doi:10.1097/AOG.0000000000002414

7. Wei G, Harley F, O'Callaghan M, et al. "Systematic review of urological injury during caesarean section and hysterectomy." Int Urogynecol J. 2023;34(2):371–389. doi:10.1007/s00192-022-05339-7

8. Blackwell RH, Kirshenbaum EJ, Shah AS, et al. "Complications of recognized and unrecognized iatrogenic ureteral injury at time of hysterectomy: a population based analysis." J Urol. 2018;199(6):1540–1545. doi:10.1016/j.juro.2017.12.067

9. Tonyali S, Yilmaz M, Tzelves L, et al. "Predictors of ureteral strictures after retrograde ureteroscopic treatment of impacted ureteral stones: a systematic literature review." J Clin Med. 2023;12(10):3603. doi:10.3390/jcm12103603

10. Reicherz A, Eltit F, Scotland K, et al. "Indwelling stents cause severe inflammation and fibrosis of the ureter via urothelial-mesenchymal transition." Sci Rep. 2023;13(1):5492. doi:10.1038/s41598-023-31885-1

11. Shokeir AA, El-Diasty T, Eassa W, et al. "Diagnosis of ureteral obstruction in patients with compromised renal function: the role of noninvasive imaging modalities." J Urol. 2004;171(6 Pt 1):2303–2306. doi:10.1097/01.ju.0000124928.69055.10

12. Richter F, Irwin RJ, Watson RA, Lang EK. "Endourologic management of benign ureteral strictures with and without compromised vascular supply." Urology. 2000;55(5):652–657. doi:10.1016/s0090-4295(00)00484-2

13. Lu C, Zhang W, Peng Y, et al. "Endoscopic balloon dilatation in the treatment of benign ureteral strictures: a meta-analysis and systematic review." J Endourol. 2019;33(4):255–262. doi:10.1089/end.2018.0797

14. Kowalski F, Kuffel B, Późniak M, et al. "Determining appropriate indications for the self-expanding, metallic stents in the treatment of ureteral strictures of different etiology." Int J Surg. 2026. doi:10.1097/JS9.0000000000004909

15. White C, Stifelman M. "Ureteral reimplantation, psoas hitch, and Boari flap." J Endourol. 2020;34(S1):S25–S30. doi:10.1089/end.2018.0750

16. Buffi NM, Lughezzani G, Hurle R, et al. "Robot-assisted surgery for benign ureteral strictures: experience and outcomes from four tertiary care institutions." Eur Urol. 2017;71(6):945–951. doi:10.1016/j.eururo.2016.07.022

17. Yang KK, Asghar AM, Lee RA, et al. "Robot-assisted laparoscopic distal ureteroureterostomy for distal benign ureteral strictures with long-term follow-up." J Endourol. 2022;36(2):203–208. doi:10.1089/end.2021.0315

18. Lee Z, Waldorf BT, Cho EY, et al. "Robotic ureteroplasty with buccal mucosa graft for the management of complex ureteral strictures." J Urol. 2017;198(6):1430–1435. doi:10.1016/j.juro.2017.06.097

19. 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

20. 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

21. 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

22. Launer BM, Redger KD, Koslov DS, et al. "Long-term follow up of ileal ureteral replacement for complex ureteral strictures: single institution study." Urology. 2021;157:257–262. doi:10.1016/j.urology.2021.07.012

23. Xiong S, Zhu W, Li X, et al. "Intestinal interposition for complex ureteral reconstruction: a comprehensive review." Int J Urol. 2020;27(5):377–386. doi:10.1111/iju.14222

24. Xu YM, Feng C, Kato H, Xie H, Zhang XR. "Long-term outcome of ileal ureteric replacement with an iliopsoas muscle tunnel antirefluxing technique for the treatment of long-segment ureteric strictures." Urology. 2016;88:201–206. doi:10.1016/j.urology.2015.11.005

25. Han DS, Johnson JP, Schulster ML, Shah O. "Indications for and results of renal autotransplantation." Curr Opin Nephrol Hypertens. 2023;32(2):183–192. doi:10.1097/MNH.0000000000000860

26. Afferi L, Gallioli A, Territo A, et al. "Robotic ileal ureter replacement vs kidney autotransplantation for long ureteric strictures." BJU Int. 2025;135(6):1031–1038. doi:10.1111/bju.16704

27. Cowan NG, Banerji JS, Johnston RB, et al. "Renal autotransplantation: 27-year experience at 2 institutions." J Urol. 2015;194(5):1357–1361. doi:10.1016/j.juro.2015.05.088

28. Reus C, Brehmer M. "Minimally invasive management of ureteral strictures: a 5-year retrospective study." World J Urol. 2019;37(8):1733–1738. doi:10.1007/s00345-018-2539-5

29. Caamiña L, Pietropaolo A, Prudhomme T, et al. "Endourological management of ureteral stricture in patients with renal transplant: a systematic review of literature." J Endourol. 2024;38(3):290–300. doi:10.1089/end.2023.0478

30. Lucignani G, Rivetti A, Prudhomme T, et al. "Reconstructive versus palliative management of ureteral stenosis after kidney transplant: an EAU-YAU Kidney Transplantation Working Group collaboration." World J Urol. 2025;43(1):439. doi:10.1007/s00345-025-05824-w

31. Sanz-Serra P, Etcheverry B, Fiol M, et al. "Robotic repair of ureteral strictures after kidney transplantation." Transplantation. 2025;109(5):853–859. doi:10.1097/TP.0000000000005237

32. Chen B, Alford AV, Lonze BE, Zhao LC. "Single-port robotic-assisted ureteral reconstruction for management of strictures after renal transplantation." Am J Transplant. 2023;23(11):1800–1805. doi:10.1016/j.ajt.2023.06.009

33. Johnsen N, Wessells H, Archer-Arroyo K, et al. Best Practices Guidelines: Management of Genitourinary Injuries. American College of Surgeons; 2025.