double-J Ureteral Stent Research Articles

Forgotten/retained double J ureteric stents: A source of severe morbidity in children.

Background:The increase in the usage of double J (DJ) ureteral stents in the management of a variety of urinary tract disease processes mandates familiarity with these devices, their consequences and their potential complications, which at times can be devastating. We retrospectively reviewed our series of children with forgotten/retained DJ ureteric stents.Materials and Methods:Hospital records of all patients’ <18 years old who underwent removal of forgotten/retained DJ ureteral stent at our hospital were reviewed for age, gender, indication for insertion of DJ stent, duration of stent insertion, radiological images and surgical procedures performed.Results:During the study period, January 2000 to December 2014 (a 15-year period), a total of 14 children underwent removal of forgotten/retained DJ ureteral stent. A combination of extracorporeal shock wave lithotripsy, cystolitholapaxy and percutaneous nephrolithotomy was done to free the DJ stent and extract it.Conclusions:Forgotten/retained stents in children are a source of severe morbidity, additional/unnecessary hospitalisation and definitely financial strain.

The Role of Tandem Double-J Ureteral Stents in the Management of Malignant Ureteral Obstruction.

The management of malignant ureteral obstruction (MUO) is a challenging but common problem for urologists. The different techniques currently used to address this complicated issue include percutaneous nephrostomy, extra-anatomical stents, retrograde (single) stent insertion, and metallic stents. In those situations where single ureteral stent insertion has failed, retrograde tandem or twin ureteral stent (TUS) insertion can be completed. The aim of this study was to report our clinical experience and also assess the efficacy of TUS insertion within our tertiary referral center. Data were prospectively collected from patients requiring TUSs over an 8-year period between January 1, 2006, and December 31, 2014. A number of variables, including the improvement in renal function following TUS insertion, were recorded. Twenty-two TUS insertion procedures were performed on 15 patients between the period of January 1, 2006, and December 31, 2014. The mean patient age was 68.0 years (39-85 years). There were 15 primary insertions as well as 7 subsequent stent changes. The average prenephrostomy creatinine was 428 μmol/L; an average improvement of 196 μmol/L was observed after percutaneous drainage. Serum creatinine after TUS remained stable on discharge, 214 μmol/L vs 227 μmol/L preoperatively, p = 0.34. Eleven patients died at a median 131 days post-TUS insertion. TUS failure occurred in three patients; this was characterized by rising creatinine and worsening hydronephrosis. Patients with failing TUS had a median life expectancy of 45.6 days compared with 162.5 days for those with functioning TUS (p < 0.05). Overall, the patency rate at 3 months was 80%. TUS insertion is a technically efficient and effective procedure in the management of MUO, with the majority of patients treated dying of the underlying condition with functioning stents in situ.

18 Incidence of bacterial colonisation after indwelling of double-J ureteral stent

18 Incidence of bacterial colonisation after indwelling of double-J ureteral stent

The use of the magnetic-end ureteric double-J stent for short term ureteric stenting

The use of the magnetic-end ureteric double-J stent for short term ureteric stenting

Unfriendly Filter: An Unusual Cause of Hydronephrosis and Hematuria

A 67-year-old woman was referred to the urology clinic for abdominal pain and hematuria. Urine analysis showed microscopic hematuria. Computed tomography urogram revealed a misplaced inferior vena cava (IVC) filter in the right gonadal vein causing right hydronephrosis. Retrograde pyelography revealed a 3-cm ureteral narrowing at the level of the IVC filter. A double-J ureteral stent was placed in the right ureter prior to exploratory laparotomy, which revealed partial erosion of the IVC filter into the right ureter and a thrombosed right ovary. The patient underwent a right oophorectomy and removal of the misplaced IVC filter. Her postoperative course was uncomplicated.

Intracardiac migration of ureteral double-J stent: A case report and review.

Ureteral double-J (DJ) stenting is a common urologic procedure in several ureteral surgeries and has been used to manage ureteral obstructions during pregnancy. It may result in early and late complications. We review a rare case of migration of the DJ stent into the cardiovascular system in a pregnant female. We also review the literature. The endoscopic procedure to remove this displacement has been done postnatally with no adverse effects.

Flexible ureterorenoscopy results: Analysis of 279 cases

In this study, the outcomes of 279 cases in whom we performed retrograde intrarenal surgery (RIRS) were evaluated retrospectively. RIRS was performed on 279 cases with the aid of access sheath of guidewire between March 2011 and February 2015. All patients were operated in the standard lithotomy position. A hydrophilic guidewire was inserted with the aid of rigid ureterorenoscopy and we checked whether there were any residual ureteral stones and other pathologies. Fluoroscopy was used routinely in all cases. Stone fragments smaller than 3 mm were left off but those bigger than 3 mm were removed by grasper after stone fragmentation. Controls of the patients were assessed by plain films (KUB), urinary tract ultrasonography (US) and/or computed tomography (CT) 1 month after the operation. Success rate of the procedure was defined as the stone-free status or presence of residual fragments less than 3 mm. 152 of the patients were male and 127 were female. The median ages of the male and female patients were 47.7 (1-86) ve 45.9 (3-79) years respectively. The median stone size was 13.5 mm (8-25). Preoperatively 34 (12.1%) patients had double-J ureteral stent. 19 (6.8%) patients were operated while they were still receiving antithrombotic and antiplatelet therapy Solitary kidney was present in 24 patients while the remaining patients had kyphoscoliosis (n=3), rotation anomaly (n=6), pelvic kidney (n=2), double collecting system (n=3), and horseshoe kidney (n=6). In 264 patients access sheath was used, in 15 patients operation was performed with the help of the guidewire. Double-J stents were inserted to 14 patients because of ureteral stricture and they underwent operation after 2 weeks later. Renal stones of 219 patients among all cases were fragmented completely and the patients were discharged as stone free (SF). Our success rate (SF or presence of clinically insignificant residual [CIRF]) was 78.4%. Stone size (p=0.029), stone number (p=0.01), stone location (p=0.023) had significant influence on the stone-free rate after RIRS The mean operation and floroscopy time was 62.5 min. (40-180) and 29.8 sec (4-96), respectively. The mean hospitalization time was 26.4 hours (12-72). Double J stents were placed to 253 patients for more stone burden and ureteral edema. Any complication was not observed for all cases except perioperative developed infection for two patients. With advances in laser technology and flexible ureterorenoscopy, kidney stones can be treated with lower morbidity and high success rates.

Novel Strategy for Temporary Decompression of the Lower Urinary Tract in Neonates Using a Ureteral Stent

In children with congenital obstructive uropathy, including posterior urethral valves, lower urinary tract decompression is recommended pending definitive surgical intervention. Current options, which are limited to a feeding tube or Foley catheter, pose unappreciated constraints in luminal diameter and are associated with potential problems. We assess the impact of luminal diameter on the current draining options and present a novel alternative method, repurposing a widely available stent that optimizes drainage. We retrospectively reviewed patients diagnosed with posterior urethral valves between January 2013 and December 2014. In all patients a 6Fr 12 cm Double-J ureteral stent was advanced over a guidewire in a retrograde fashion into the bladder. Luminal flow and cross-sectional areas were also assessed for each of 3 tubes for urinary drainage, ie 6Fr Double-J stent, 5Fr feeding tube and 6Fr Foley catheter. A total of 30 patients underwent uneventful bedside Double-J stent placement. Mean ± SD age at valve ablation was 28.5 ± 16.6 days. Mean ± SD peak serum creatinine was 2.23 ± 0.97 mg/dl after birth and 0.56 ± 0.22 mg/dl at the procedure. Urine output after stent placement was excellent in all patients. The Foley catheter and feeding tube drained approximately 18 and 6 times more slowly, respectively, and exhibited half the calculated cross-sectional luminal area compared to the Double-J stent. Use of Double-J stents in neonates with posterior urethral valves is a safe and effective alternative method for lower urinary tract decompression that optimizes the flow/lumen relationship compared to conventional drainage options.

Subcapsular renal hematoma after ureteroscopy with holmium:yttrium-aluminum-garnet laser lithotripsy.

Subcapsular renal hematoma (SRH) after ureteroscopic lithotripsy (URSL) using holmium:yttrium-aluminum-garnet (Ho:YAG) laser to treat ureteric stones is a rare complication. We aimed to review our unit's experience of post-URSL subcapsular renal hematoma. From 2006 to 2012, 2059 URSLs using F9.5 rigid ureteroscope were performed in our unit. Patients with post-URSL symptomatic renal hematoma were reviewed. Perioperative information on patients' renal function, stone characteristics, and degree of renal hydronephrosis were reviewed. Operative data, postoperative information such as clinical manifestation, changes in blood parameters, CT findings, and subsequent treatment were documented. Of the 2059 patients treated with URSL and Ho:YAG laser, three patients were diagnosed as subcapsular renal hematoma after surgery; the age is 57, 61, and 63years old, respectively. Preoperative imaging examination showed that two patients and one patient had obstructing middle and proximal ureteral stones ranging in size from 0.8 to 1.6cm, and three patients had thin renal cortices. The double-J ureteral stents were inserted in all cases regularly. All three subcapsular renal hematoma patients had the loin pain of the operation side and fever, and one patient had significant hemoglobin drop (from 111 to 61g/L) who need to transfusion. Two patients presented within 24h of URSL, and one patient presented on day 10. One patient was treated conservatively for 3weeks and recovered with bed rest, antibiotics, hemostasis, and analgesia with no intervention or drain. The other two patients underwent ultrasonography-guided drainage of the hematoma. Two-month follow-up CT scans or ultrasonography confirmed the resolution of the hematoma in all three cases. Renal subcapsular hematoma after URSL is a rare and one of serious complications. Subcapsular renal hematoma should be considered when patients have the symptoms of significant loin pain after URSL for obstructing ureteral stones with thin renal cortices. The treatment of post-URSL renal subcapsular hematomas needs to be customized for each patient.

V7-09 ROBOT-ASSISTED LAPAROSCOPIC URETEROCALICOSTOMY IN THE PEDIATRIC PATIENT

You have accessJournal of UrologyPediatrics1 Apr 2015V7-09 ROBOT-ASSISTED LAPAROSCOPIC URETEROCALICOSTOMY IN THE PEDIATRIC PATIENT Ashley Wietsma, Patricia Cho, and Richard Yu Ashley WietsmaAshley Wietsma More articles by this author , Patricia ChoPatricia Cho More articles by this author , and Richard YuRichard Yu More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1940AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Ureterocalicostomy is a versatile alternative to the traditional Anderson-Hynes pyeloplasty in the treatment of recurrent ureteropelvic junction (UPJ) obstruction, UPJ obstruction associated with anatomic anomalies, such as horseshoe kidney and intrarenal pelvis, and trauma of the UPJ or proximal ureter. Although the robotic approach has become increasingly popular for urologic reconstructive procedures in the adult and pediatric populations, little data has been published on robot-assisted laparoscopic ureterocalicostomy especially in the pediatric population. To illustrate the feasibility of this minimally invasive approach in pediatrics, we present a case series with one representative video of robotic ureterocalicostomy. METHODS Four patients with an age range of 11 to 22 years (average age 15 years) with equal gender distribution underwent robot-assisted laparoscopic ureterocalicostomy for left UPJ obstruction between 2011 and 2014. In all patients, preoperative ultrasound revealed severe hydronephrosis with diffuse cortical thinning. Preoperative renal scans (MAG3 or DMSA) demonstrated decreased differential renal function on the affected left side in a range of 29-40% (average 31%), and obstructive parameters with a diuretic half-time in the range of 19 to greater than 100 minutes (average time 51 minutes). Half of the patients underwent planned, salvage ureterocalicostomy reconstruction due to recurrent UPJ obstruction following traditional pyeloplasties. Utererocalicostomy was indicated as a primary procedure for the other two patients due to anatomic abnormalities, an intrarenal pelvis and complex ureteral anatomy. RESULTS There were no intraoperative complications. Double-J ureteral stents were placed intraoperatively in each patient. Mean hospital stay was 1.5 days. Stents were removed less than 7 weeks postoperatively. Postoperative ultrasound demonstrated persistent, but stable hydronephrosis, an unsurprising result given their history of long-standing obstruction and severe hydronephrosis. Two patients experienced recurrent flank pain, but renography revealed a widely patent anastomosis. CONCLUSIONS Robotic ureterocalicostomy is a feasible and successful procedure for recurrent and severe UPJ obstruction in pediatric patients. Its versatility allows for its application for both pyeloplasty failure and as an alternative procedure for cases of challenging renal and ureteral anatomy. More data is necessary to quantify the advantages and disadvantages of the robotic approach as compared to open and laparoscopic approaches. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e661-e662 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ashley Wietsma More articles by this author Patricia Cho More articles by this author Richard Yu More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

The effects of silodosin in the treatment of ureteral stent related symptoms

The aim of the present study was to evaluate the outcome of silodosin in improving the lower urinary tract symptoms of patients with indwelling double-J ureteral stents. We reviewed the data of 89 male patients with ureteral stones who had undergone placement of a double-J ureteral stent after retrograde ureteroscopy at Pusan National University Hospital in South Korea from June 2011 to May 2013. The patients enrolled in the study were sorted into two groups. Forty-six patients who were given silodosin (8 mg) once daily were sorted as group A, and forty-three patients who received no α1-blocker were sorted as group B (control group). All patients completed international prostate symptoms score/quality of life component of IPSS (IPSS/QoL) and visual analogue pain scale (VAPS) questionnaires 6 weeks after the stent placement. The mean age of all the patients was 57.9 ± 12.8 years (range, 27–84 years). There was a significant difference in the IPSS—total score (p = 0.029), storage subscore (p = 0.035) and voiding subscore (p = 0.017)—and QoL scores (p = 0.041), but no significant differences in the VAPS (p = 0.210). The present study showed that silodosin improved stent-related urinary symptoms and QoL without causing any serious side effects. Further clinical research in this area is warranted to better define the role of silodosin in current clinical practice.

Role of removing stasis and reducing heat formula in clearance of proximal ureteral calculi after ureteroscopic Ho:YAG laser lithotripsy: a prospective randomized study.

To prospectively evaluate the efficacy of Removing Stasis and Reducing Heat Formula in accelerating calculus clearance and improving lower urinary tract symptoms of patients with proximal ureteral calculi after ureteroscopic Ho:YAG laser lithotripsy. A total of 138 patients with proximal ureteral calculi underwent ureteroscopic Ho:YAG laser lithotripsy by a single endocrinologist. Stone size varied from 10 to 15 mm. After operation, the patients were randomly divided into three groups: the control group (group A), tamsulosin group (group B), and Removing Stasis and Reducing Heat Formula group (group C). The treatment lasted for 4 weeks or until stone clearance. The primary and secondary outcomes of the three groups at follow-up were assessed. Of the 131 patients available for follow-up, 44 cases were in the group A, 45 in the group B, and 42 in the group C, respectively. The stone free rate at 2 weeks in the groups B and C were significantly higher than that in the group A (95.56%, 97.62% vs. 79.55%; all P<0.05). The ureteral colic rate and mean time of fragment expulsion were significantly reduced in the groups B (4.44% and 7.86±4.99 days) and C (2.43% and 6.76±4.37 days) compared with the group A (22.73% and 11.54±9.89 days, all P<0.05). On the day of double-J ureteric stent removal, the group C differed significantly from the group A in the total International Prostate Symptom Score, irritative subscore, obstructive subscore, and quality of life score (all P<0.05). Removing Stasis and Reducing Heat Formula in the medical expulsive therapy might be an effective modality for patients with calculus in the proximal uretera after ureteroscopic Ho:YAG laser lithotripsy.

A rare complication of ureteral double-J stenting after flexible ureteroscopy: renal parenchymal perforation.

Double-j (DJ) ureteral stenting is a very common procedure performed after various endourological procedures. Although several complications due to DJ stent insertion were revealed, only three cases of renal parenchymal perforation have been reported to date. We present a case of a 35-year-old woman who had perforation of renal parenchyma without perirenal hematoma following insertion of DJ ureteral stent after flexible ureteroscopy for the treatment of an upper ureteral calculi. Non-contrast computed tomography was used for diagnosis. Patient was successfully managed with repositioning of the stent under fluoroscopic guidance on postoperative second day postoperatively.

Retained fragmented double J ureteric stent: A report of four cases with review of the literature.

Polyurethane double-J ureteral stents are widely used in the field of urology. Postoperatively, patient education about the ureteral stent and making sure it is removed at the prescribed time is an utmost necessity. Forgotten ureteral stent is not only disastrous for the patient but also fraught with serious medico-legal implications for the urologist. Herein, we present four cases of long-term retained part of ureteral stent with its varied presentation and subsequent management.

The full metallic double-pigtail ureteral stent: Review of the clinical outcome and current status.

The full metallic double-J ureteral stent (MS) was introduced as a method for providing long-term drainage in malignant ureteral obstruction. Experimental evaluation of the MS revealed that its mechanical features allow efficient drainage in difficult cases, which could not be managed by the insertion of a standard polymeric double-J stent. Clinical experience with the MS showed controversial results. Careful patient selection results in efficient long-term management of malignant ureteral obstruction. The use of the MS should also be considered in selected benign cases. Major complications are uncommon and the minor complications should not hinder its use. Experience in pediatric patients is limited and warrants additional study. The cost-effectiveness of the MS seems to be appropriate for long-term treatment. Further investigation with comparative clinical trials would document the outcome more extensively and establish the indications as well as the selection criteria for the MS.

Bacterial characteristics and clinical significance of ureteral double-J stents in children

ObjectiveTo determine the incidence of urinary tract infection in those patients that we have used an ureteral double-J stent as internal diversion after urological procedures. Materials and methodsWe reviewed all the medical records of patients who had a ureteral double-J stent after a urological procedure from August 2007 to May 2013. We have analyzed the following data: age, gender, type of prophylaxis, incidence of urinary tract infection (UTI), days of internal diversion with double-J stent, surgical procedure, bacterial characteristics, bacterial sensibility to antibiotics and UTI treatment. ResultsWe have used 73 double-J stents as ureteral internal diversion in 67 patients with a mean age of 44.73±57.23. Surgical procedures were 50 laparoscopic Anderson-Hynes pyeloplasties in 49 patients, and 20 high-pressure balloon dilatation of the ureterovesical junction to treat primary obstructive megaureter in 15 patients; and 3 patients with ureterovesical obstruction after endoscopic treatment of vesicoureteral reflux. Forty three stents showed a bacterial colonization in cultures. Pseudomonas aeruginosa was present in 9 (20.9%) stents. Only in 12 stents, bacterial colonization was sensible to antibiotic prophylaxis. Stent colonization was higher in boys and younger patients. Four patients had a febrile UTI. Incidence of UTI in younger patients that underwent HBPD of UVJ is higher. ConclusionBacterial colonization is frequent in double-J stents but the incidence of UTI is low. Double-J colonization is higher in younger patients. Patients that underwent HPBD have a higher risk of UTI related with ureteral double-J stent.

An unusual complication of a double-J ureteral stent: renal parenchymal perforation in a solitary kidney.

Double-J ureteral stenting is commonly used in urological practice and has various complications. We report a patient with a renal parenchymal perforation and perirenal hematoma due to a double-J ureteral stent in a solitary kidney. This complication of ureteral stents is rarely observed and is life-threatening.

Duplicated, Ectopic Ureter Inserting into the Prostatic Urethra During Robot-Assisted Radical Prostatectomy

Introduction: Robot-assisted radical prostatectomy has been shown to be a valuable therapeutic option for patients with clinically localized prostate cancer. In the era of cost savings and avoiding unnecessary tests, patients with intermediate-risk prostate cancer have been recommended against preoperative cross-sectional imaging techniques such as CT or MRI. Ureteral duplication associated with ectopia is a rare finding in men and insertion of the ectopic ureter occurs above the external sphincter or pelvic floor. In the literature, this clinical presentation has been reported in five case reports.1–5 Materials and Methods: We present the case of an otherwise healthy 67-year-old male who was found to have an elevated prostate-specific antigen (PSA), which prompted a transrectal ultrasound-guided biopsy of the prostate demonstrating Gleason 3 + 4 adenocarcinoma in the left mid and base. A prostate examination showed an ∼90-g gland that was otherwise benign, therefore clinical stage T1c. He denied lower urinary tract symptoms, erectile dysfunction, or family history for prostate cancer. After weighing all treatment options, he proceeded to robot-assisted radical prostatectomy and pelvic lymph node dissection. From an anterior approach during anterior cystotomy, he was discovered to have left-sided complete ureteral duplication with the upper pole inserting into the prostatic urethra. The bladder neck was widened to ensure identification of ureteral orifices and confirmation of the anatomy. Results: Following confirmation of the above anatomy by dissecting out the ureters at the level of the pelvic brim and observing indigo carmine excretion from the ectopic ureter, we placed a Double-J ureteral stent to identify and protect the ureter while proceeding with our posterior cystotomy. Ultimately, we performed complex bladder neck reconstruction to displace the stented ectopic ureter posteriorly and laterally, while completing the vesicourethral anastomosis using the routine Van Velthoven technique. Final pathology revealed Gleason 3 + 4, pT2cN0 adenocarcinoma of the prostate with negative surgical margins. Conclusions: After a satisfactory cystogram demonstrating contrast refluxing through the stent to the upper pole and no contrast extravasation, the patient's catheter was removed at 3 weeks postoperatively. He returned 1 month later for ureteral stent removal through flexible cystoscopy. The first PSA recheck at 3 months returned as undetectable and the patient continued with routine prostate cancer surveillance. As shown in the above case, excellent oncologic outcomes can be obtained with complex bladder neck reconstruction when encountering a duplicated, ectopic ureter inserting into the prostatic urethra during robotic radical prostatectomy. If the ectopic ureteral orifice appears too distal to the bladder neck, we recommend performing ureteral reimplantation or ureteroureterostomy to maintain adequate cancer control. All authors have no competing financial interests. Presented at: 31st World Congress of Endourology & SWL, October 22nd–26th, 2013, New Orleans, LA. Runtime of video: 7 mins 58 secs

Efficacy of tamsulosin hydrochloride in relieving "double-J ureteral stent-related morbidity": a randomized placebo controlled clinical study.

To evaluate the efficacy of tamsulosin therapy in reducing ureteral double-J stent morbidity by evaluating USSQ, IPSS, QOL and VAS (primary objective) and to evaluate the morbidity and or complication(s) associated with indwelling double-J ureteral stent(s) and to evaluate the safety of tamsulosin therapy for "morbidity associated with double-J stents" by evaluating its tolerability, side effects and adverse events if any (secondary objective) as per protocol. After institutional review board approval, 60 consecutive patients with a double-J ureteral stent inserted after percutaneous nephrolithotomy or ureteroscopic stone treatment were randomly assigned to receive tamsulosin 0.4 mg, or a placebo for 4 weeks. The validated USSQ, VAS and IPSS were completed before stent insertion, at 3 days and 4 weeks after stent insertion and at 2 weeks after stent removal. Data were statistically analyzed for efficacy and tolerability of one drug over the other using Wilcoxon signed-rank test, Mann-Whitney test and Student's t test. Patients receiving tamsulosin compared with the placebo showed significant decrease in urinary index score, pain index score, work performance score, VAS score at loin area, VAS score at flank, VAS score at suprapubic area, average VAS score, need for antibiotics, number of hospital visits (P < 0.05) at the end of fourth weeks. Decrease in values were also observed in IPSS score, general health score, quality of sex score and IPSS-quality of life (QOL) score in patients taking tamsulosin but, however, the decrease was not significant. No patients discontinued medication because of side effects. We conclude that ureteral stenting using double-J stents with concomitant tamsulosin therapy was generally well tolerated, safe, effective and significantly beneficial in reducing stent morbidity in the majority of our patients. We advocate the routine use of concomitant tamsulosin therapy in eligible patients undergoing ureteral stenting in order to minimize stent morbidity.

Biodegradable rapamycin-eluting ureteral stent inhibits scar formation after ureteral injuriy

Objective To evaluate the effect of biodegradable rapamycin-eluting ureteral stent in inhibiting scar formation after ureteral injuries.Methods Smooth muscle cells were primary cultured.The inhibitory effect of rapamycin on the proliferation of smooth muscle cells was investigated by methyl thiazol tetrazolium (MTT) detection.And then,the optimal drug concentration was selected to construct drug-eluting stent.Biodegradable rapamycin-eluting ureteral stent and double-J stent were surgically implanted into the traumatic ureteral injury animal model,to evaluate the inhibitory effect in situ by histological tests.Results Smooth muscle cells were successfully cultured in vitro,and the results of MTT confirmed rapamycin could effectively inhibit the proliferation of smooth muscle cells depending on concentration.The IC50 was 23.3 mg/L.All stents were successfully implanted.At 18 weeks,masson trichrome and α-smooth muscle actin (α-SMA) immunohistochemical staining showed that biodegradable rapamycin-eluting ureteral stent,compared with double-J stent,can effectively inhibit the excessive proliferation of smooth muscle cells and collagen deposition.Conclusion Biodegradable rapamycin-eluting ureteral stent can effectively inhibit the excessive proliferation of smooth muscle cells and collagen deposition,thereby preventing ureteral scar stenosis. Key words: Rapamycin eluting stent; Ureteral injury; Scar formation