Abstract
Background:
Intraoperative localization of ureteral strictures and safe placement of double-J stents are pivotal steps during laparoscopic reconstruction, yet practical guidance on these steps is limited.
Objective:
To introduce a simple and feasible new method of using ureteroscopy-assisted localization and indwelling double-J tubes in laparoscopic repair of middle and lower ureteral stenosis, and to confirm its safety and effectiveness.
Methods:
We conducted a single-center, two-period retrospective comparison of patients undergoing laparoscopic reconstruction for middle or lower ureteral stricture. The control cohort (2010–2017) used conventional laparoscopic localization with trocar-assisted guidewire/stent placement, whereas the experimental cohort (2018–2023) used ureteroscopy-assisted localization with transureteral guidewire/stent placement under simultaneous laparoscopic visualization. Primary outcomes were time to localize the stricture and time to place the double-J stent.
Results:
A total of 49 patients were included in the experimental cohort and 56 in the control cohort. Ureteroscopy assistance shortened stricture localization time (138 ± 24 versus 174 ± 12 min; mean difference [MD] −36; 95% CI −43.5 to −28.5; p=0.02) and double-J stent placement time (5.2 ± 0.6 versus 9.8 ± 2.4 min; MD −4.6; 95% CI −5.26 to −3.94; p=0.01). Estimated blood loss, drain duration, time to first flatus, and stent malposition rates were similar between groups.
Conclusions:
Ureteroscopy-assisted localization and transureteral stent placement may streamline laparoscopic reconstruction for middle and lower ureteral strictures by reducing operative time without compromising safety. Prospective studies with longer follow-up are warranted. Ureteroscopy-assisted double-J stent.
Introduction
The incidence of iatrogenic ureteral strictures has been rising with the increasing use of ureteroscopy, laparoscopy and robotic surgeries, 1 other causes may include congenital narrowing, 2 retroperitoneal fibrosis, 3 and may require reconstructive procedures for durable relief of obstruction. 4 While laparoscopic ureteroneocystostomy (with or without a Boari flap) and segmental ureteroureterostomy are established options, two practical intraoperative issues remain under-described: (i) reliable localization of a tight stricture within adhesions and (ii) efficient, safe placement of a double-J stent.
Existing literature predominantly emphasizes anastomotic techniques and long-term patency, 5 offering limited procedural guidance on real-time stricture localization and the logistics of stent placement during laparoscopy. 6 In particular, trocar-based guidewire delivery can be ergonomically demanding and time-consuming, potentially increasing surgeon fatigue without clear benefits over transureteral approaches. 7
We compared a conventional laparoscopic strategy with a ureteroscopy-assisted approach designed to (a) improve localization using endoscopic illumination/palpation cues and (b) simplify transureteral guidewire/stent placement under laparoscopic visualization. We hypothesized that ureteroscopy assistance reduces key operative intervals without compromising perioperative safety.
Materials and methods
Study design and setting
This single-center, retrospective comparative study included two non-concurrent cohorts from a tertiary referral hospital. The control cohort (January 2010–December 2017) underwent conventional laparoscopic repair with laparoscopic localization and trocar-assisted guidewire/stent placement. The experimental cohort (January 2018–April 2023) underwent ureteroscopy-assisted localization with transureteral guidewire/stent placement under simultaneous laparoscopic visualization. All consecutive eligible cases during each period were included.
Inclusion criteria
(1) Single, benign ureteral stricture located below the iliac crest on imaging (intravenous urography, retrograde ureterography, or CT urography);
(2) Stricture length <2 cm.
Exclusion criteria
(1) Multiple strictures; (2) Bladder contracture; (3) Active severe urinary tract infection; (4) Stricture >2 cm; (5) Stricture above the iliac crest; (6) Follow-up <6 months; (7) Refusal of laparoscopic reconstruction; (8) Significant cardiopulmonary disease precluding laparoscopy.
Baseline characteristics
Baseline demographics, side, etiology, and prior interventions were similar between cohorts (Table 1). No clinically meaningful between-group differences were detected.
Baseline characteristics.
Numbers are rounded.
Surgical techniques
All procedures were performed in low lithotomy and 30° Trendelenburg using three trocars (one 12-mm umbilical camera port and two working ports). The ureter was mobilized with preservation of adventitial blood supply; the stricture was resected and oblique spatulation was created. Reconstruction consisted of ureteroneocystostomy (with or without a Boari flap) or end-to-end ureteroureterostomy.
Experimental cohort (ureteroscopy-assisted)
When adhesions obscured the stricture, a semirigid ureteroscope was advanced transureterally to the distal stricture. Intermittent light modulation and gentle tip palpation facilitated external identification of the distal extent, enabling a controlled distal-to-proximal release with minimal ureterolysis. After partial mucosa-to-mucosa anastomosis (barbed 4-0 suture on one side), a guidewire was advanced through the ureteroscope into the proximal ureter, followed by transureteral double-J stent placement under laparoscopic visualization.
Control cohort (conventional)
Guidewire placement was performed through a 12-mm trocar, with laparoscopic instruments directing the wire into the proximal ureter under direct vision; anastomotic steps paralleled the experimental cohort.
Postoperative care and follow-up
All patients had a pelvic drain and ureteral catheter placed. Drains were removed when output was <50 mL/day. Ureteral catheters were removed at 1–2 weeks. Double-J stents were removed at approximately 4 weeks in the clinic. Ultrasound at 3 and 6 months assessed hydronephrosis (anteroposterior diameter >1 cm).
Outcomes
Primary outcomes were time to localize the stricture (from start of ureteral dissection to identification of the distal extent) and time to place the double-J stent.
Secondary outcomes included estimated blood loss, drain duration, stent malposition (upper coil not in renal pelvis or lower coil not in bladder on radiograph), time to first flatus, and ultrasound-defined hydronephrosis at 3 and 6 months. Reinterventions for symptomatic restenosis were recorded.
Operational definitions: “Localization time” was measured from the start of ureteral dissection to complete release of the distal extent of the stricture. “Double-J stent placement time” was measured from the start of guidewire/stent insertion (via ureteroscope or trocar) to completion of stent deployment. Estimated blood loss was calculated as suction canister volume minus irrigant volume. Drain duration was the time to drain removal after output fell below 50 mL/day.
Statistical analysis
Continuous variables are presented as mean ± SD and compared using independent-samples t tests; Welch correction was applied when variances were unequal. Normality was assessed using the Shapiro–Wilk test and inspection of Q–Q plots. Categorical variables were compared using χ² tests (or Fisher’s exact test when appropriate). For the two primary outcomes, we report mean differences (MD) with 95% confidence intervals (CI). A two-sided p < 0.05 was considered statistically significant; multiplicity adjustments were not applied because the coprimary outcomes were prespecified and complementary. Analyses were performed in SPSS (version 18.0; SPSS Inc., Chicago, IL, USA). Because all eligible cases were included, no a priori sample size calculation was performed; this is acknowledged as a limitation. Missing data were rare and analyzed using a complete-case approach.
Results
A total of 120 patients were screened; 15 were excluded for incomplete imaging data. 105 patients met eligibility criteria and were analyzed (49 experimental; 56 control).
Perioperative outcomes
Compared with the conventional approach, the ureteroscopy-assisted approach significantly reduced both stricture localization time and stent placement time (Table 2). Estimated blood loss, drain duration, time to first flatus, and stent malposition rates were similar between groups. No intraoperative stent malposition was noted on postoperative radiographs at 1 month.
Perioperative outcomes.
MD = mean difference; CI = confidence interval.
Values are presented as mean ± SD unless otherwise specified.
Follow-up
At 3 months, ultrasound showed hydronephrosis >1 cm in 5/49 experimental and 7/56 control patients; by 6 months, this persisted in 3/49 and 4/56, respectively. Two experimental-cohort and four control-cohort patients with persistent hydronephrosis and flank discomfort underwent reinterventions at the treating surgeon’s discretion.
Discussion
Distal ureteral strictures are common in urology and can be managed with endoluminal treatments (e.g., balloon dilation 8 with temporary Allium stent placement) 9 or reconstructive surgery. However, ureteroneocystostomy remains the standard option for short distal strictures (typically <2 cm).10,11 Prior literature has focused mainly on anastomotic techniques 12 (e.g., submucosal tunnel technique, 13 nipple technique 14 ) and long-term patency,15,16 whereas less attention has been paid to intraoperative localization of the stricture and practical methods for double-J stent placement.
There are methods for locating strictures using contrast agents, 17 but their use has some limitations. 18 In cases where the ureter has undergone previous surgical procedures or inflammation, the identification of ureteral strictures is difficult because the anatomy of the ureter is unclear, especially for middle and lower segment strictures and tight iliac vascular adhesions. In such cases, a narrow focus becomes particularly important, especially when there are important organs and blood vessels nearby. Given our limited early experience, cases with severe adhesions often required a significant amount of time. This led us to seek a simple method for accurately locating the stenosis. Blindly cutting a possible pipeline poses a significant risk. At the same time, surgeons must remove the entire lesion segment to ensure the outcome of the surgery, including laparoscopic and robotic repair of ureteral stenosis due to the lack of tactile feedback. Using this method, ureteroscopy can effectively help locate the stenosis during surgery, especially in cases with a history of surgery. The shaking of the ureteroscope and the light source can effectively and quickly locate the distal end of the stenosis. By finding the distal end of the stenosis and gradually cutting it open to the proximal end, this is a safe method. Using conventional methods to free the ureter, due to the difficulty of adhesion around the ureter, a wide range of free movements is required to effectively determine the site of stenosis, which is time-consuming and prone to fatigue for the operator. Mechanistically, transurethral ureteroscopic illumination and gentle tip palpation helped identify the distal extent of the stricture under laparoscopy, enabling a controlled distal-to-proximal release with limited ureterolysis. 19 Likewise, delivering the guidewire and stent via the ureteroscope mirrored routine endourologic practice, minimizing instrument exchanges and facilitating accurate intraluminal positioning. Several groups have used indocyanine green (ICG) near-infrared fluorescence to aid ureteral identification and stricture localization, either via retrograde intraluminal instillation for mapping or intravenous ICG to assess anastomotic perfusion 20 ; while effective, these methods require fluorescence-capable imaging and dye preparation and may be limited by poor upstream filling across a tight stricture. In contrast, our transurethral, ureteroscopy-assisted approach provides real-time intraluminal guidance without radiation and was associated with shorter step-specific intervals and comparable safety in our cohort. Surgical fatigue has a significant impact on the later fine suturing process. We also faced this problem in the early stage. The fatigue of both hands cannot ensure the precision of the suturing, which is why we conducted this research.
Most physicians use laparoscopic trocar implantation of guide wires, which are inserted into the ureter under laparoscopy. This method requires high laparoscopic skills and the ability to adjust the relative position of the separating forceps and ureter at any time to ensure the smooth implantation of the guide wire. At the same time, an assistant is needed to fix the outer end of the guide wire; otherwise, it is easy to cause guide wire displacement and slippage. Because the end of the ureter is located in the pelvic cavity, while the trocars of laparoscopy are all located below the navel, this requires the guide wire to pass through the trocar and enter the ureteral opening downwards, then bend back and enter the renal pelvis upwards. This method often requires an increase in the number of trocars to assist in the completion when the ureter is not sufficiently free. At the same time, the operator needs to reverse the clamping, fixation, and delivery of the guide wire, which is prone to shoulder and elbow fatigue. This fatigue is most common in laparoscopic ureteral lithotomy, and has a significant impact on the subsequent need for fine suturing. At present, robot-assisted laparoscopy is widely used, and it is relatively easy to place double-J tubes under robot-assisted laparoscopy. However, robots are still only available in large medical centers. 20 After we adopted this method of assisting with the ureteroscopy, the placement of the double-J stent was significantly smoother and less tiring, and it did not interfere with the subsequent suturing process. In this study, ureteroscopy assistance was associated with shorter stricture localization time and faster double-J stent placement. The observed mean differences (36 min for localization and 4.6 min for stent placement; 95% CIs reported in the Results) are clinically meaningful during complex pelvic dissection, potentially reducing operative fatigue and anesthesia exposure.
This study has limitations: the retrospective, two-period design without randomization; potential learning-curve effects that may contribute to faster operative steps over time; a relatively short 6-month follow-up for detecting restenosis; and nonstandardized preoperative hydronephrosis measurements across referrals. Prospective studies with standardized imaging protocols and longer follow-up are warranted to validate durability and to isolate any learning-curve contribution. Because this retrospective analysis included all eligible cases from two nonconcurrent periods, no a priori sample size calculation was performed. Another significant limitation of this study is the small sample size, which makes it impossible to eliminate the biases caused by the learning curve. Moreover, as it is a nonprospective controlled study, it is impossible to achieve a complete and accurate collection of relevant factors. As a result, the study may be underpowered for some secondary endpoints, and the observed effect sizes should be interpreted with caution. In general, this method is simple to use. Compared with the laparoscopic trocar method, this method is simple and practical. Adopting this method is in line with the natural shape of the ureter, similar to daily double-J stent indwelling, and the operation is relatively simple. At the same time, laparoscopic combined with ureteroscopy can greatly help determine the location of stenosis and reduce surgical time. For patients who require laparoscopic repair of the middle and lower ureter, it is worth trying this method. Finally, the follow-up period was limited to six months, which may be inadequate to detect late restenosis or delayed complications after reconstruction. Prospective studies with standardized imaging and longer follow-up are warranted to assess durability.
Conclusions
Ureteroscopy-assisted localization and transureteral double-J stent placement are practical adjuncts during laparoscopic reconstruction of middle and distal ureteral strictures. In our experience, these steps shorten key operative intervals and may reduce surgeon fatigue while maintaining safety (Figure 1).

Ureteroscopy-assisted double-J stent placement. (a) Boari flap; (b) ureteroscope; (c) ureteral anastomosis; (d) guidewire; (e) double-J stent.
Footnotes
Ethical Considerations
The institutional ethics committee of the Second Affiliated Hospital of the Army Medical University approved this study (approval number: 2025study-226-01). All patients provided written informed consent. The study adhered to the Declaration of Helsinki. Trial registration was not required for this retrospective study.
Consent to participate
Written informed consent was obtained from all subjects before the study. Yes, Verbal informed consent was obtained from all subjects before the study. Written informed consent was obtained from legally authorized representatives before the study. Verbal informed consent was obtained from legally authorized representatives before the study. Informed consent was not sought for the present study because the reaesrch uses retrospectively collected anonymized data that cannot be traced back to individual participants, and the study protocol has been approved by the Medical Ethics Committee of the Second Affiliated Hospital of the Army Medical University with a waiver of informed consent requirements.
Author contributions
Conceptualization: Wu Ronghua; Methodology: Wu Ronghua, Yang Jianghua; Investigation and data curation: Yi Shanhong, Fu Weihua, Chang Pengkang, Li Yang, Song Yajun; Formal analysis: Zheng Ji; Writing original draft: Wu Ronghua; Writing—review & editing: all authors; Supervision: Zhang Bo.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by the Science and Health Joint Project of Chongqing (No. 2024MSXM071).
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Data availability statement
The datasets generated and analyzed during the current study are available from the corresponding author on reasonable request.
Trial registration
*NAME OF TRIAL REGISTRY: Not applicable*
This randomized clinical trial was not registered because it was designed as an observational retrospective study, and registration was not mandated by local research regulations at study initiation.* Thank you for your attention to the research protocol. Due to the nature of the observational retrospective study, no clinical registration was conducted. This study has passed the ethical review. If necessary, we are still willing to cooperate in conducting clinical registration.*
