A ureteral stricture is characterized by a narrowing of the ureteral lumen, causing functional obstruction. The most common form of ureteral stricture is ureteropelvic junction (UPJ) obstruction, which is a congenital or acquired narrowing at the level of the UPJ (see Ureteropelvic Junction Obstruction).
The ureter is a muscular tube lined by transitional epithelium that courses from the renal pelvis to the bladder in the retroperitoneum.
The length of the ureter is 20-30 cm, depending on the individual's height. The lumen size is 4-10 mm in circumference, depending on its location. The narrowest areas include the UPJ, the overpass by the ureter where it crosses over the bifurcation of the iliac arteries, and the ureterovesical junction (UVJ).
In both men and women, the ureter courses posterior to the gonadal vessels and anterior to the iliopsoas muscles, crosses the common iliac artery and vein, and enters inferiorly into the pelvis. In men, the vas deferens loops anterior to the ureter, prior to the ureter entering the bladder. In women, the ureter courses posterior to the uterine arteries (hence, the "water under the bridge" analogy) and close to the uterine cervix prior to reaching the intramural bladder.
The ureteral blood supply is provided from multiple sources. Superiorly, branches from the renal and gonadal arteries may contribute. As the ureter courses through the retroperitoneum, the aorta contributes numerous small branches. In the pelvis, the iliac, vesical, uterine, and hemorrhoidal arteries also contribute to the ureteral blood supply.
Ureteral strictures are typically due to ischemia, resulting in fibrosis. Wolf and colleagues define a stricture as ischemic when it follows open surgery or radiation therapy, whereas the stricture is considered nonischemic if it is caused by spontaneous stone passage or a congenital abnormality.[1] Less commonly, the etiology is mechanical, such as from a poorly placed permanent suture or surgical clip.
Pathologic analysis of the strictures reveals disordered collagen deposition, fibrosis, and varying levels of inflammation, depending on factors such as etiology and interval since the causative insult.
The resulting ureteral obstruction may vary widely from mild, causing only asymptomatic proximal ureteral dilation and hydronephrosis, to severe, causing complete obstruction and subsequent loss of renal function.
Some patients with ureteral strictures are asymptomatic; others are symptomatic only during periods of diuresis or develop severe renal colic. The degree of symptoms correlates poorly with the degree of obstruction; at times, severe obstruction is asymptomatic or silent. Renal failure and azotemia may be due to bilateral strictures, such as in cases of bilateral ureteroenteric strictures, external compression due to retroperitoneal malignancy, or retroperitoneal fibrosis; recovery depends on the duration of ureteral obstruction.
Extrinsic malignant strictures include those caused by primary or metastatic cancer. Primary pelvic malignancies, particularly cancers of the cervix, prostate, bladder, and colon, frequently cause extrinsic compression of the distal ureter. Retroperitoneal lymphadenopathy, caused by a wide range of malignancies, particularly lymphoma, testicular carcinoma, breast cancer, or prostate cancer, may cause proximal to midureteral obstruction.
Extrinsic benign compression due to idiopathic retroperitoneal fibrosis may also cause unilateral or bilateral ureteral obstruction, leading to azotemia.
Transitional cell carcinoma (TCC) may cause malignant intrinsic obstruction.
Malignant ureteral obstruction is differentiated from benign ureteral obstruction by (1) the presence of an extrinsic mass on a CT scan or sonogram and (2) the appearance of the ureter on contrast-study images.
Ureteral TCC may manifest as ureteral obstruction. Ureteral TCCs typically have an irregular mucosal pattern and are associated with dilatation of the ureter below the lesion (goblet sign). Benign strictures are usually smooth, without distal dilatation. In some cases, biopsy may be required to differentiate benign from malignant strictures. Biopsy samples can usually be collected ureteroscopically or with a fluoroscopically directed ureteral brush. Ureteral tumors can also be diagnosed during transureteral resection of the tumor with specialized ureteral resectoscopes.
Benign intrinsic strictures, which are the focus of this article, may be congenital (eg, congenital obstructing megaureter), iatrogenic, or noniatrogenic (eg, those that follow passage of calculi or chronic inflammatory ureteral involvement [eg, tuberculosis and schistosomiasis]).
Iatrogenic benign strictures may result from various causes, including the following:
The widespread use of upper tract endoscopy has led to an increased frequency of iatrogenic ureteral stricture. Early ureteroscopy studies reported ureteral stricture rates of 3%-11% in patients undergoing ureteroscopy for calculus management. More recent studies using smaller fiberoptic endoscopes; laser lithotripsy; and smaller, less traumatic instruments report a ureteral stricture rate of less than 1%.
In a review of 24 patients with highly impacted ureteral stones that were impacted for an average of 11 months, 24% of the patients developed postoperative ureteral strictures; therefore, impaction is a major risk factor. Ureteral perforation during these procedures has also been identified as a risk factor for stricture disease.[2, 3]
Factors associated with ureteral stricture development during ureteroscopy include the following:
Large scope size
Prolonged case duration
Stone impaction
Stone size
Proximal location
Perforation
Use of intracorporeal lithotripsy
Ureteral strictures occur in approximately 3-8% of kidney transplant recipients.[4] Ureteral strictures may complicate urinary diversions. The frequency of ureterointestinal anastomotic strictures during urinary diversion is 3%-5%. Ureteral injuries may result from any pelvic or retroperitoneal surgery, particularly abdominal hysterectomy and sigmoid colectomy. Gynecologic surgery is responsible for up to 75% of iatrogenic ureteral injuries.
Vakili et al performed a prospective analysis of 479 patients undergoing hysterectomy for benign disease.[5] Iatrogenic ureteral injury occurred in 8 patients (1.7%), comparable with previous ranges reported in the literature (0.02%-2.5%). Risk factors for urinary tract injury during hysterectomy include malignancy, pelvic radiation, endometriosis, prior surgery, and surgery for prolapse, although at least half of all ureteral injuries have no identifiable risk factors. Ureteral injuries or injury repairs may also result in strictures, although strictures of these etiologies are less common than strictures caused during endoscopy or anastomosis.
Obtain a detailed patient history and pay particular attention to symptoms during periods of diuresis (eg, after ingestion of caffeinated or alcoholic drinks). Take note of any history of prior malignancy, surgery, or radiation therapy. Important physical examination findings include abdominal pain, fullness or tenderness, and costovertebral angle tenderness.
Ureteral strictures are often found during routine follow-up imaging after ureteroscopy or intestinal urinary diversion. In this setting, asymptomatic hydroureteronephrosis proximal to the site of obstruction may occur. Most patients with significant strictures after ureteroscopy are symptomatic. They present with flank pain, flank fullness, or abdominal fullness.
In a review of 131 patients who underwent ureteroscopy and follow-up radiographic imaging, Karod et al found no asymptomatic patients with residual obstruction.[6] Thirteen of 21 patients with persistent flank pain had residual obstruction, one from a ureteral stricture.
Less frequently, persistent urinary tract infection or pyelonephritis is associated with unilateral ureteral obstruction. Patients with preexisting renal insufficiency or an abnormal contralateral kidney may present with an increased serum creatinine level or azotemia. Also, patients with strictures in solitary or functionally solitary kidneys (eg, renal transplant patients) may present with renal failure.
Imaging studies used for the assessment of ureteral stricture include the following:
Renal ultrasonography
Computed tomography
Intravenous pyelography (IVP)
Retrograde pyelography
Nuclear medicine diuretic scan
Intraluminal ultrasonography[7]
Magnetic resonance imaging (MRI)
Renal ultrasonography
Renal ultrasonography is often the initial imaging study performed to evaluate for ureteral strictures because the findings are highly sensitive for hydronephrosis, the study is noninvasive, and the evaluation requires no intravenous contrast. Limitations of ultrasonography include fairly poor ureteral imaging, especially in patients who are obese, and the fact that this study is anatomic rather than functional.
Computed tomography
Noncontrast helical computed tomography (NCCT) is now commonly used to evaluate patients with acute flank pain and is therefore often performed in patients with a history of calculus disease. NCCT findings are highly sensitive and specific for helping reliably identify hydroureteronephrosis and the site of dilatation. In addition, ureteral wall thickness, imbedded or extruded calculi, and urinary extravasation can be appreciated.
Secondary signs of obstruction (eg, periureteral stranding) can also be appreciated and do not require intravenous contrast for detection; however, NCCT is not a functional study and cannot be used to reliably estimate the degree of obstruction or relative renal function.
The addition of intravenous contrast to the CT scan allows assessment of the degree of obstruction, and a delayed nephrogram is often present. Delayed views provide important information regarding anatomic relationship of the strictured ureter to the adjacent structures. Contrast use must be counterbalanced by the nephrotoxicity of the contrast and the risk of adverse contrast reaction. Contrast CT scanning may be the best test for evaluating extrinsic causes of obstruction and evaluating regional or metastatic disease when malignant ureteral obstruction is evaluated.
Intravenous pyelography
IVP was once the traditional functional imaging study of choice. Since the widespread availability of CT scanning, IVP is rarely used.
IVP is particularly valuable in patients who have partial obstruction with normal renal function, but this imaging study is impaired by the risks of intravenous contrast. See the images below.
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Ureteral stricture. Intravenous pyelogram (IVP) in a woman 4 weeks after a total abdominal hysterectomy for endometriosis. A ureteral injury was ident....
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Ureteral stricture. The same patient as in the image above, after a combined antegrade and retrograde endoureterotomy of the completely obliterated st....
Retrograde pyelography
This study very useful because it yields excellent ureteral-mucosal detail in the absence of intravenous contrast and is often used in preparation for endoscopic or open surgery to repair a ureteral stricture. Limitations include relative invasiveness and a requirement for cystoscopy. See the image below.
View Image
Ureteral stricture. This right retrograde pyelogram reveals a tight right midureteral stricture in a man 3 years after an aortobifemoral bypass for ob....
Nuclear medicine diuretic scan
This the most widely used test to measure the degree of obstruction and to quantify relative renal function. The diuretic renal scan is used to measure clearance of the radiopharmaceutical over time and to calculate renal blood flow, which correlates with relative renal function.
The most common radiopharmaceuticals currently used to evaluate relative function and obstruction include technetium-99m (Tc 99m) mercaptoacetyltriglycine, which is primarily a tubular agent, and Tc 99m diethylenetriamine pentaacetic acid, which is primarily a glomerular agent. At the peak uptake of the radiopharmaceutical, intravenous furosemide, usually 20 mg, may be administered to induce diuresis and to allow the assessment of urinary clearance.
Relative disadvantages of nuclear medicine diuretic scans include the following:
Its qualitative nature
User dependence
Lack of informative anatomic data
Intraluminal ultrasonography
According to some authors, intraluminal ultrasonography is useful to help evaluate ureteral obstruction. Advantages include the ability to assess ureteral submucosal and periureteral abnormalities (eg, fibrosis, vascular structures). Disadvantages include an invasive nature and an inability to assess complete or near-complete obstruction.
Magnetic resonance imaging
MRI may be useful for evaluating patients with a renal transplant who have renal failure and in whom ultrasonographic findings are normal or equivocal.
Histologic findings of benign ureteral strictures are nonspecific. Scar formation with collagen deposition and inflammatory infiltrate may be prominent. Radiation strictures may demonstrate a lack of cellularity and vascular hypertrophy with acellular matrix. Malignant strictures have characteristics of the specific carcinoma pathology, most commonly TCC.
Strictures may be staged based on location and severity. Location is divided into proximal (UPJ to sacrum), mid (over sacrum), and distal (inlet of pelvis to UVJ). Severity commonly refers to the degree of urinary obstruction (ie, mild, moderate, severe).
No accepted medical treatment of ureteral strictures currently exists. Surgical procedures used in these patients include the following:
Balloon dilation
Endoureterotomy
Placement of metal ureteral stents
Open surgery
Laparoscopic and robot-assisted laparoscopic surgery are increasingly used to replicate the results offered by open surgery.
Indications for intervention in patients with ureteral strictures include pain, infection, or obstruction, which may threaten a patient's renal function. Less common indications may include stone formation proximal to an obstruction or hematuria.
The major contraindication to ureteral stricture surgery (endoscopic or open) is an active and untreated urinary tract infection. A relative contraindication is uncorrected bleeding diathesis.
When ureteral stricture surgery (endoscopic or open) is contemplated, many patient factors should be considered.
If the patient has a terminal malignancy, is extremely elderly, or has a high surgical risk and tolerates internal stenting well, long-term stenting may be most appropriate. Chung et al analyzed 101 patients with extrinsic ureteral obstruction managed with indwelling ureteral stents.[8] Within 1 year, the stents failed in 41% of the patients. Thirty percent of patients needed percutaneous nephrostomy tube placement at a mean of 40 days. Predictors of stent failure included cancer, a baseline creatinine level of greater than 1.3 mg/dL, and poststent systemic treatment.
If the affected kidney has less than 25% function, balloon dilation and endoureterotomy are more likely to fail.[1] Therefore, the patient is at significant risk for eventually requiring open surgery or nephrectomy. Few data exist on the outcomes of open surgery based on preoperative renal function. Renal function may significantly improve in some patients with poor function due to obstruction after the obstruction is corrected. If the renal function is less than 10%, recovery is unlikely and initial nephrectomy may be most appropriate.
The most common initial management of benign ureteral strictures is balloon dilation, followed by stent placement for 4-6 weeks. Hafez and Wolf reviewed 8 published series of ureteral strictures managed with balloon dilation.[9] Success rates ranged from 48%-88%. Of the 280 ureteral strictures treated, the overall mean success rate was 55%. They found balloon dilation best suited for very short nonischemic strictures.
Goldfischer and Gerber summarized the results of balloon dilation in a large series and found this procedure to yield a success rate of 50%-76%.[10] Factors associated with a good outcome included short duration (< 3 mo) and short length of stricture. Given the frequent need for multiple procedures and the higher success rate associated with endoureterotomy, most urologists recommend endoscopic incision as the initial minimally invasive management of ureteral stricture disease.[11]
Laser endopyelotomy with balloon dilation is associated with good outcomes in treatment-naïve patients with short (< 2 cm), non-ischemic, benign ureteral strictures with a functional renal unit. However, If stricture recurs, repetitive dilation and laser endopyleotomy has low success rates.[12]
Endoureterotomy
Patients with low-complexity ureteroenteric strictures and transplant strictures may benefit from endoscopic treatment options, although formal reconstruction offers higher rates of success.
Endoureterotomy is commonly performed for benign strictures and boasts a higher success rate than balloon dilation. Hafez and Wolf reviewed 8 published series of endoureterotomy for benign stricture disease and found success rates of 55-85%.[9] The overall success rate was 78% in the 156 patients. Goldfischer and Gerber found that an endoureterotomy has a success rate of 62-100%.[10] In a large review assessing endoureterotomy and factors associated with success, Wolf et al found a success rate of 82% for benign strictures.[1] Poor renal function (< 25% overall function), long strictures (>1 cm), and tight stricture lumen (< 1 mm) are associated with a poorer outcome. Wolf et al found that the use of triamcinolone injection into the stricture bed and large stents (>12F) are useful for long strictures (>1 cm).[1] Recent long-term studies indicate a success rate of closer to 50% after 5-year follow-up.
Ureteral metal stents
Metal stents, which have been used to treat end-stage malignant disease, provide proximal decompression, although recurrence of the obstruction is possible. Stent removal is extremely difficult, and stent migration has been reported. Some attempts to apply them to benign ureteral strictures and UPJ obstruction and ureterovesical obstruction have been made. Liatsikos et al reported on their experience of 102 patients with a total of 142 ureters stented.[13] The primary stent patency rate was 66%. They did not report on the time interval in which the stents became occluded.
Liatsikos and colleagues also reported on their experience using self-expandable metal stents for ureteroileal anastomotic strictures.[14] They treated a total of 24 ureteroileal conduits with a technical success of 100% and an immediate postoperative clinical success rate of 70.8%. The 1- and 4-year primary patency rates were 37.8% and 22.7%, respectively. Despite the high occlusion rates, the authors contend that the placement of metal stents is appropriate in patients who may not be candidates for open surgery.
Innovations in the materials and design of ureteric stents will likely continue. A number of metallic microcoiled stents coated with polymers that retard stone growth are currently on the market. These stents can be used in patients who require long-term stent changes or in those with malignant obstruction due to terminal illness. The stents can be changed every 6-12 months. Periodic cystoscopy to rule out stent encrustations has been recommended.
Open surgical management
Open surgical management includes various treatment options such as psoas hitch, Boari flap, ureteroneocystostomy, transureteroureterostomy (TUU), intestine interposition, renal mobilization, and autotransplant. All open procedures carry an increased risk of morbidity, increased recovery time, and increased hospitalization time compared with endoscopic approaches.
The surgical approach used depends primarily on the location of the ureteral stricture. Distal strictures that require open repair are best managed with ureteroneocystostomy or a psoas hitch, depending on the proximity to the ureteral orifice. If more length is required, a Boari flap can bridge a 10- to 15-cm defect and may reach the mid ureter.
For midureteral strictures, a primary ureteroureterostomy may be appropriate for short benign strictures with minimal tension. TUU may be used if the donor ureter is of adequate length and the recipient ureter is not diseased. Relative contraindications to TUU (see Transureteroureterostomy) include conditions that may affect both ureters (eg, TCC, urolithiasis, radiation, chronic infection, retroperitoneal fibrosis).
Proximal ureteral strictures may be managed with ureteropyelostomy if length allows. Also, ureterocalicostomy is useful if the renal pelvis is scarred or intrarenal in location.
Long, complex upper tract ureteral strictures have traditionally been managed with nephrectomy, bowel interposition, and autotransplantation. For long, extensive ureteral strictures that are not amenable to repair with urothelium, ileal ureteral substitution may be a satisfactory solution. Franke and Smith have stated that contraindications to ileal ureter substitution include renal insufficiency (serum creatinine level >2 mg/dL), bladder outlet obstruction, inflammatory bowel disease, and radiation enteritis.
In a retrospective review of 51 patients who underwent renal autotransplantation, kidney function was preserved postoperatively and 2 graft losses occurred. Complication rates compared favorably with those of other major urological operations and cold ischemia time was the only predictor of postoperative complications.[15]
Laparoscopic and robot-assisted laparoscopic repair
Laparoscopic and robot-assisted laparoscopic surgery are increasingly used to replicate the results offered by open ureteral stricture surgery. Simmons and colleagues (2007) retrospectively compared 12 patients who underwent laparoscopic surgery with 34 patients who underwent open ureteroureterostomy, ureteroneocystostomy, and Boari flap procedures.[16, 17] The average operative blood loss was 258 mL in the open group versus 86 mL in the laparoscopic group; the hospital stay was a median of 5 days in the open group versus 3 days in the laparoscopic group. The overall complication rate was higher in the open group (15%) than in the laparoscopic group (8%). No significant differences were found in the patency or duration of follow-up between the two groups.
Tran et al, reviewed analyzed the results of 52 patients who underwent laparoscopic nephrectomy with autotransplantation for complex ureteral and renal conditions included ureteral stricture disease. The study found a greater than 90% success rate with longer than 6-year median followup.[18]
Fugita and colleagues reported 3 successful cases of distal ureteral stricture treated with laparoscopic Boari flap creation.[19] Modi et al reported the successful use of laparoscopic ureteroneocystostomy with psoas hitch in 6 patients with ureterovaginal fistula in whom endoscopic management initially failed.[20] The first reported use of laparoscopic ureteroureterostomy was published in 1998 and detailed 9 patients with symptomatic endometriosis of the ureter treated with resection and primary repair.[21] One patient had recurrent stricture that responded to endoscopic dilation.
With the increasing availability of the da Vinci robot system, this technology has been successfully applied to ureteral stricture disease. It offers the advantage of easier intracorporal suturing and knot tying. Multiple centers have reported small case series documenting successful treatment of distal ureteral stricture with robot-assisted laparoscopic reimplantation, with and without psoas hitch or Boari flap.[22, 23, 24]
Assessing the anatomic details of the stricture is paramount and is often best accomplished with retrograde pyelography and CT scanning with delayed contrasted views. The degree of preoperative obstruction and the relative renal function of the ipsilateral and contralateral kidneys are important. This assessment is usually performed using nuclear renal scanning.
The location of the surrounding vascular anatomy may be important, depending on the stricture site. The location can be delineated preoperatively with using images from spiral CT scanning, magnetic resonance angiography, or intraluminal ultrasonography, if necessary.
Consider collecting a biopsy sample from the stricture in patients with a prior malignancy (eg, ureterointestinal anastomotic stricture after radical cystectomy).
To decrease the risk of perioperative infection, the patient should have a sterile urine culture prior to surgical or endoscopic treatment.
Perform a preoperative mechanical and antibiotic bowel preparation in patients in whom an ileal ureter substitution is a possibility.
An antegrade or retrograde endoureterotomy may be performed, but note that a retrograde endoureterotomy has the advantage of avoiding percutaneous renal access.
Then, ureteral incisions can be performed with an endoscopic cold knife, a small (3F) electrocautery probe, or holmium:YAG laser. The Acusize cutting balloon, with its electrocautery wire over the dilating balloon surface, may also be used under fluoroscopic, rather than endoscopic, guidance. Keep in mind that this is a blind cut when only fluoroscopy is used. This can result in vascular complications, even in patients with normal anatomy.
Incisions should be of full thickness into periureteral fat and for 1-2 cm proximal and distal to the stricture. At times, postincisional dilation may facilitate complete incision. The orientation of the incision should vary depending on the location of the stricture in the ureter. In general, the incision should be directed posterolateral in the proximal ureter, from the UPJ to the iliac vessels, directly anterior over the iliacs, and anteromedial below the vessels. Endoluminal ultrasound may assist with the identification of the periureteral vessels.
Postoperative stenting with a 7F-14F stent for 4-6 weeks is commonly performed.
Ureteroneocystostomy
Ureteroneocystostomy and a psoas hitch can be performed through a Pfannenstiel or lower midline incision, although the lower midline approach is more versatile and can be extended if needed. Both a Boari flap and TUU can be performed through midline incisions. Proximal ureteral surgery can be performed through dorsal lumbotomy or flank incisions, but, if TUU or ileal substitution is considered, the midline approach is most versatile.
All ureteral anastomosis should be widely spatulated and free of tension. Ureteral adventitia should be carefully preserved to avoid injuring the ureteral blood supply. Absorbable sutures are recommended to avoid a nidus for calculus formation. Most ureteral anastomoses in adults are stented with indwelling stents to promote drainage and to minimize urine extravasation. The duration of stenting is controversial; 10-21 days is most common for anastomotic repairs. Drains are sometimes placed postoperatively. Use of a Foley catheter can preclude drainage in many cases.
Ureteroneocystostomy and a psoas hitch should be performed with attention to avoid obstruction. The usefulness of tunneled anastomoses in adults is probably small because the risk of obstruction is likely greater than the risk of reflux. Pantuck and colleagues compared end-to-side direct and nonrefluxing anastomosis following urinary diversion after cystectomy.[25] They found a significant increase in ureteral stricture in the nonrefluxing group, while the development of hydronephrosis, pyelonephritis, and stone formation did not significantly differ.
Transureteroureterostomy
When performing a TUU, care must be taken to avoid kinking as the ureter crosses the sigmoid mesentery. If possible, this tunnel should be superior to the inferior mesenteric artery.
Ileal substitution should be performed in an isoperistaltic fashion to avoid urinary stasis and to promote drainage.
Antibiotics are used perioperatively and may be continued for 24 hours or until drains are removed.
Drains are left in place until output is minimal (< 30 mL/d) or the drainage is confirmed to be serum, which is accomplished by checking the drain creatinine level. In patients who received an endoureterotomy, stents are left in place for 4-6 weeks. In patients who received anastomotic repairs, stents are left in place for 10-21 days.
If a nephrostomy tube was placed in the patient, it is typically removed last because it can be used to perform antegrade nephrostography to confirm patency.
Complications of balloon dilation include the following:
Infection
Failure to successfully dilate
Loss of renal access
Subsequent need for percutaneous nephrostomy drainage
Complications of endoureterotomy include the following:
Infection
Failure to successfully dilate
Loss of renal access
Subsequent need for percutaneous nephrostomy drainage
Direct injury to adjacent structures (eg, bowel or vascular structures, urinoma formation)
Vascular injury: Yamada et al reported that 1 of 20 patients treated with a cold-knife ureterotomy had a major vascular injury that required an immediate laparotomy.[26]
Complications of open surgical repair include the following:
Prolonged ileus
Urinoma
Prolonged urine leak from repair
Bowel injury
Sepsis
Late adhesion formation
Small bowel obstruction
Risks of major surgery (eg, deep venous thrombosis, myocardial infarction, surgical mortality)
Impaired bladder function (may occur after psoas hitch or Boari flap)
The success rate of balloon dilation is 48%-88%, with a mean of approximately 55%. The length and location of the stricture are important factors, with short and distal strictures responding best.
The success rate of endoureterotomy used to manage benign strictures is 78%. Higher success rates are achieved in nonischemic strictures, those shorter than 1 cm, and those treated less than 24 months from the etiologic event. In addition, the use of a large stent (>12F) is associated with a better outcome, as is stenting for less than 4 weeks.
The success rate of endoureterotomy used to manage ureteroenteric strictures is 32% at 3 years. Right ureteroenteric strictures tend to have better outcomes compared with left ureteroenteric strictures. Large stents (>12F) are associated with better outcomes, as is longer stenting, ie, over weeks.[1]
The success rate of balloon dilation used to manage ureteral strictures after renal transplantation is 45%-79%. Antegrade or retrograde cold-knife incision has a success rate of 82% at 26 months.
The success rate of open surgical repair of ureteral strictures is over 90%.
A current controversy involves the usefulness of intralesional injection of steroids to inhibit stricture recurrence. In a retrospective review of 77 endoureterotomies, Wolf et al found that the injection of intralesional triamcinolone was associated with greater success in strictures longer than 1 cm.[1] The significance of this observation in an uncontrolled review is uncertain.
The future of ureteral stricture management may involve extraurinary tissue used as grafts or vascular pedicle flaps to replace damaged portions of ureter. Naude reported the successful use of buccal mucosal grafts with omental wrap in 4 patients with segmental ureteric loss.[27] An artificial ureter crafted from silicone-polyester was used in two renal transplant patients with ureteral stricture in whom endoscopic and open repair had failed.[28] At 12 and 15 months of follow-up, the renal function was stable, with no evidence of obstruction.
Innovative tissue engineering technology may produce ureteral tissue that closely mimics native ureteral tissue for ureteral replacement. Some groups have used xenogenic acellular collagen membranes such as porcine small intestine submucosa for ureteral reconstruction. Atala is using similar technology to engineer bladder, cavernosal, urethral, and ureteral tissue.[29]
Early follow-up imaging studies are typically performed 2-4 weeks after stent removal and include renal ultrasonography, IVP, or renal scintigraphy. A serum creatinine evaluation and urine culture are often performed.
If the patient is asymptomatic, imaging is performed at 3 months and then at 6-month intervals for the first 2 years. Most stricture recurrences are identified within the first year after surgery.
For excellent patient education resources, see eMedicineHealth's patient education articles Intravenous Pyelogram, Magnetic Resonance Imaging (MRI), and CT Scan.
Benjamin Newell Breyer, MD, MS, Assistant Professor, Trauma and Reconstruction, Department of Urology, University of California, San Francisco, School of Medicine
Disclosure: Nothing to disclose.
Coauthor(s)
Christopher J Kane, MD, FACS, Professor of Surgery, Chief of Urology, University of California, San Diego, School of Medicine
Disclosure: Nothing to disclose.
Specialty Editors
Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Received salary from Medscape for employment. for: Medscape.
Chief Editor
Bradley Fields Schwartz, DO, FACS, Professor of Urology, Director, Center for Laparoscopy and Endourology, Department of Surgery, Southern Illinois University School of Medicine
Disclosure: Serve(d) as a director, officer, partner, employee, advisor, consultant or trustee for: AUA Journal of Urology<br/>Serve(d) as a speaker or a member of a speakers bureau for: Cook Medical; Olympus, .
Additional Contributors
Daniel B Rukstalis, MD, Professor of Urology, Wake Forest Baptist Health System, Wake Forest University School of Medicine
Ureteral stricture. Intravenous pyelogram (IVP) in a woman 4 weeks after a total abdominal hysterectomy for endometriosis. A ureteral injury was identified intraoperatively and repaired by the gynecologist. The IVP image reveals a high-grade right distal ureteral stricture.
Ureteral stricture. The same patient as in the image above, after a combined antegrade and retrograde endoureterotomy of the completely obliterated stricture with holmium:YAG laser, subsequent dilation to 15F with a ureteral dilating balloon, and stenting with a double-J ureteral stent. The image is an antegrade nephrostogram prior to removal of the nephrostomy tube. The patient is asymptomatic and stent-free without obstruction 3 months after the procedure.
Ureteral stricture. This right retrograde pyelogram reveals a tight right midureteral stricture in a man 3 years after an aortobifemoral bypass for obstructive peripheral vascular disease. The man presented with azotemia and bilateral hydroureteronephrosis to the mid ureters. Bilateral stents were placed, and subsequent bilateral ureterolysis with omental wrapping was performed. Both ureters were encased in a dense inflammatory process anterior to the vascular graft.
Ureteral stricture. Intravenous pyelogram (IVP) in a woman 4 weeks after a total abdominal hysterectomy for endometriosis. A ureteral injury was identified intraoperatively and repaired by the gynecologist. The IVP image reveals a high-grade right distal ureteral stricture.
Ureteral stricture. The same patient as in the image above, after a combined antegrade and retrograde endoureterotomy of the completely obliterated stricture with holmium:YAG laser, subsequent dilation to 15F with a ureteral dilating balloon, and stenting with a double-J ureteral stent. The image is an antegrade nephrostogram prior to removal of the nephrostomy tube. The patient is asymptomatic and stent-free without obstruction 3 months after the procedure.
Ureteral stricture. This right retrograde pyelogram reveals a tight right midureteral stricture in a man 3 years after an aortobifemoral bypass for obstructive peripheral vascular disease. The man presented with azotemia and bilateral hydroureteronephrosis to the mid ureters. Bilateral stents were placed, and subsequent bilateral ureterolysis with omental wrapping was performed. Both ureters were encased in a dense inflammatory process anterior to the vascular graft.
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