Levopositioned caudal vena cava and circumcaval left ureter with subsequent hydronephrosis and hydroureter in a dog.

The presentation and investigation of a levopositioned caudal vena cava, a rare congenital vascular abnormality seen mainly in Bernese Mountain Dogs, which resulted in ureteral compression, hydronephrosis and hydroureter. Surgical transection, transposition and anastomosis were performed to reposition the circumcaval ureter. A 19-month-old male neutered Bernese Mountain Dog was presented with a 13-month history of vague signs including intermittent abdominal pain, inappetence and diarrhoea, which were poorly responsive to medical management. Abdominal ultrasound revealed left-sided hydronephrosis and hydroureter. Further investigation included abdominal computed tomography and pre- and post-intravenous iodinated contrast, which revealed a levopositioned caudal vena cava with associated ureteral displacement to a circumcaval position, resulting in ureteral compression and proximal dilation affecting both the proximal ureter and the left kidney. The patient was also found to have concomitant gall bladder agenesis. Surgery was performed to transect, transpose and anastomose the ureter in a normal anatomical position, and the patient made an excellent clinical recovery. All gastrointestinal signs resolved within 2 weeks of surgery and remained resolved 12 months later. Follow-up ultrasound and pyelography were performed at 4-month post-surgery, revealing a mild improvement in the hydronephrosis and hydroureter. Although rare, circumcaval ureter should be considered a differential in dogs presenting with hydroureter and hydronephrosis, especially Bernese Mountain Dogs.

Laparoscopic ureteroneocystostomy in the treatment of urinary incontinence due to ectopy of the ureters in female dogs: A pilot study.

Ureteral ectopia is rare and requires surgical treatment after a thorough diagnostic workup. Open surgical techniques for repositioning ectopic ureters have been known for many years and are well described in the literature. However, to the best of our knowledge, no laparoscopic method of correcting this pathology has been described, which, in our opinion, would benefit the animal in terms of the healing process and overall clinical outcomes. This study aimed to evaluate the possibility of laparoscopic treatment of ureteral ectopia, which causes urinary incontinence in dogs. All of the operated ten dogs presented in this study were client-owned females with symptoms of urinary incontinence due to a unilateral intramural ectopic ureter. A three-trocar laparoscopic technique was used to perform the ureteroneocystostomy of the ectopic ureter. In this article, clinicopathological data, imaging features, procedural findings, complications, and short- and long-term outcomes are presented. The procedure was feasible in all cases. No major postoperative complications were observed. Among the minor complications, slight hematuria was observed in three dogs, which resolved spontaneously. In the period of at least one year after surgery, no negative impact of the procedure was observed. Seven of the ten operated dogs regained urinary continence. The remaining three dogs required additional surgery (urethral bulking) because of a lack of improvement after adjuvant pharmacological treatment. Overall, good-to-excellent long-term outcomes can be achieved; however, dogs that remain incontinent after laparoscopic ureteroneocystostomy may require additional treatment.

Ultrasonography as a sensitive and specific diagnostic modality for the detection of ectopic ureters in urinary incontinent dogs.

Ultrasonography is a widely available diagnostic modality for the identification of dogs with suspected ureteral ectopia; however published studies detailing its sensitivity and specificity are currently lacking. The aim of this retrospective, descriptive, diagnostic accuracy study was to evaluate the sensitivity and specificity of ultrasonography for the diagnosis of ureteral ectopia in incontinent dogs presenting to a referral institution, using cystoscopy as the gold standard. Medical records of urinary incontinent dogs presenting to a single institution (n = 38) were retrospectively reviewed for the presence of ureteric insertion abnormalities and concurrent urinary tract abnormalities. Ultrasonographic findings were compared with those from cystoscopic examination to determine diagnostic accuracy. The relationship between the presence of concurrent urinary tract abnormalities and ureteral ectopia was assessed using an independent samples t-test and Mann-Whitney test. Statistical significance was set at P ≤ 0.05. Ultrasonography had a sensitivity of 93.5%, specificity of 100%, and diagnostic accuracy of 95% when identifying dogs with ureteral ectopia. When classifying individual ureters as ectopic or non-ectopic, sensitivity was 87.8% and specificity was 86.7%. Dogs with ureteral ectopia had significantly more concurrent urinary tract abnormalities on ultrasound than unaffected dogs (P = 0.004). Ectopic ureters were associated with significantly more concurrent ipsilateral upper urinary tract ultrasonographic abnormalities than unaffected ureters (P < 0.001). Ultrasonography performed by an experienced ultrasonographer is a sensitive and specific screening tool for canine ureteral ectopia, which eliminates the need for heavy sedation, general anesthesia, and advanced imaging, although it should not be relied upon as the sole diagnostic modality for the assessment of individual ureters.

Four-dimensional CT excretory urography is an accurate technique for diagnosis of canine ureteral ectopia.

Computed tomographic (CT) excretory urography is commonly used to investigate canine ureteral ectopia (UE). Modern technology allows time-resolved CT imaging (four-dimensional CT excretory urography [4D-CTEU]) over a distance exceeding the detector collimation. Objectives of this prospective, observational, diagnostic accuracy study were to evaluate the diagnostic accuracy of CT excretory urography (CTEU) and 4D-CTEU for UE in dogs with lower urinary tract signs, assess the influence of pelvis positioning, and to determine the significance of the ureterovesical junction (UVJ) angle for UE diagnosis. Thirty-six dogs, with a total of 42 normotopic ureters, 27 intramural ectopic ureters, and three extramural ectopic ureters, underwent CTEU and 4D-CTEU with randomized pelvis positioning. Randomized CTEU and 4D-CTEU studies were scored by two observers for ureteral papilla location and murality on a grading scheme. Interobserver agreement, sensitivity, and specificity for ureter topia status and diagnosis were calculated. Computed tomographic excretory urography showed moderate interobserver agreement for the left ureter and perfect for the right ureter, whereas 4D-CTEU showed bilateral nearly perfect agreement between both observers. When comparing CTEU versus confirmed diagnosis, there was a sensitivity and specificity of 73% and 90.2%, respectively, whereas 4D-CTEU showed a sensitivity and specificity of 97% and 94.6%, respectively. An obtuse UVJ angle is significantly more commonly observed in ectopic intramural than normotopic ureters and is significantly associated with increased diagnostic confidence of UE. The use of a wedge to angle the pelvis did not increase the diagnostic confidence in determining ureteral opening position. Four-dimensional CT excretory urography is an accurate and reliable diagnostic technique to investigate UE as cause of urinary incontinence in dogs that is slightly superior to CTEU.

Uretero-Cutaneous Fistula and Renal Abscessation as a Complication of Ureteral Stenting in a Dog.

An 11 yr old female spayed shih tzu was referred for treatment of left ureterolithiasis with complete obstruction of the left ureter and pyonephrosis. A ureteral stent was placed surgically to relieve the obstruction and pyonephrosis was treated with antibiotics. Three and a half years following stent placement, the patient developed an abscess on the left flank with chronic purulent discharge. Diagnostic imaging confirmed the presence of a left uretero-cutaneous fistula and renal abscess. A left ureteronephrectomy was performed. The dog was euthanatized 4 mo later for cardiac insufficiency unresponsive to medical treatment. This is the first report of a uretero-cutaneous fistula and renal abscessation as a complication of ureteral stenting in a dog.

A minimally invasive surgical technique for ureteral ostioplasty in two fillies with ureteral ectopia.

CASE DESCRIPTION 2 fillies, aged 3 months and 1 month, were examined because of urinary incontinence and urine scalding. CLINICAL FINDINGS In horse 1, ultrasonography did not reveal any structural abnormalities of the kidneys; however, unilateral ureteral ectopia was diagnosed cystoscopically. In horse 2, CT revealed bilateral nephropathy, bilateral distended ureters (up to 3.6 cm in diameter), and bilateral ureteral ectopia. Cystoscopy revealed intramural ureteral ectopia with abnormally caudally positioned ureteral ostia in both horses. TREATMENT AND OUTCOME Ureteral ostioplasty was performed under cystoscopic guidance. Laparoscopic scissors (horse 1) or a vessel-sealing device (horse 2) was introduced, and the tissue separating the intramural portion of the ureter from the urethra and bladder was cut longitudinally in a cranial direction toward the trigone. After surgery, both horses were continent and voided normal streams of urine for the duration of the follow-up periods of 20 and 9 months for horse 1 and horse 2, respectively. CLINICAL RELEVANCE Cystoscopically guided ureteral ostioplasty provided an effective and minimally invasive surgical treatment option for correction of ureteral ectopia in 2 fillies.

Interventional Radiology and Interventional Endoscopy in Treatment of Nephroureteral Disease in the Dog and Cat.

Interventional endoscopy and interventional radiology have led to the development of minimally invasive techniques for management of kidney and ureteral diseases in the dog and cat including idiopathic renal hematuria, ureteral obstruction, and ectopic ureters. Sclerotherapy is a renal-sparing chemical cauterization technique used in cases of idiopathic renal hematuria. Diagnosis of ureteral obstruction is challenging in some cases based on ultrasound alone and antegrade pyelography should be considered. Treatment options for obstructions include nephrostomy tubes, ureteral stents, and subcutaneous ureteral bypass devices. Treatment with cystoscopic-guided laser ablation provides similar outcomes to surgery in dogs with intramural ectopic ureters.

Rigid urethrocystoscopy via a percutaneous fluoroscopic-assisted perineal approach in male dogs: 19 cases (2005-2014).

OBJECTIVE To describe the technique and outcome for male dogs undergoing rigid urethrocystoscopy via a novel percutaneous, fluoroscopic-assisted perineal approach. DESIGN Retrospective case series. ANIMALS 19 client-owned male dogs. PROCEDURES Medical records of male dogs that underwent urethrocystoscopy via a percutaneous perineal approach for treatment of a variety of conditions from 2005 through 2014 were reviewed. Signalment, history, pertinent diagnostic imaging results, endourologic and postprocedure details, duration of hospitalization, complications, and outcome (short-term, < 1 month; long-term, ≥ 1 month) were recorded. After flexible urethrocystoscopy, direct percutaneous perineal needle puncture and guidewire placement by means of fluoroscopic guidance (with or without ultrasonography) allowed access to the urethral lumen. The perineal tract was subsequently serially dilated to accommodate a peel-away sheath and rigid endoscope. Rigid urethrocystoscopy was performed, and on completion of endourologic procedures, the access site was left to heal by second intention. RESULTS 19 male dogs successfully underwent 20 procedures. No intraoperative complications were reported. Short-term outcome was good (ie, mild perineal urine leakage) for 3 dogs and excellent (ie, no abnormalities with urination) for 16. Long-term outcome was excellent for the 17 dogs for which follow-up information was available. CONCLUSIONS AND CLINICAL RELEVANCE A percutaneous fluoroscopic-assisted perineal approach (with or without ultrasonography) allowed access to the pelvic urethra with no major complications in the present series of patients. This minimally invasive approach may be a valuable tool for endourologic procedures in male dogs.

Outcomes of ureteral surgery and ureteral stenting in cats: 117 cases (2006-2014).

OBJECTIVE: To evaluate and compare outcomes in cats following ureteral surgery or ureteral stent placement. DESIGN: Retrospective case series. ANIMALS: 117 cats. PROCEDURES: Data regarding signalment, history, concurrent disease, clinical signs, clinicopathologic tests, surgical procedures, and perioperative complications (including death) were recorded. Follow-up data, including presence of signs of chronic lower urinary tract disease, chronic urinary tract infection, reobstruction, and death, if applicable, were obtained by records review or telephone contact with owners. Variables of interest were compared statistically between cats treated with and without stent placement. Kaplan-Meier analysis and Cox regression were performed to assess differences in survival time between cats with and without ureteral stents. RESULTS: Perioperative complications referable to the urinary tract were identified in 6 of 43 (14%) cats that had ≥ 1 ureteral stent placed and 2 of 74 (3%) cats that underwent ureteral surgery without stenting. Perioperative mortality rates were similar between cats with (4/43 [9%]) and without (6/74 [8%]) stents. After surgery, signs of chronic lower urinary tract disease and chronic urinary tract infection were significantly more common among cats with than cats without stents. Nineteen of 87 (22%) cats with follow-up information available had recurrent obstruction; incidence of reobstruction did not differ between cats with and without stents. Median survival time did not differ between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE: The potential for signs of chronic lower urinary tract disease and chronic infection, particularly among cats that receive ureteral stents, warrants appropriate client counseling. Judicious long-term follow-up for detection of reobstruction is recommended.

Ureteral implantation using a three-stitch ureteroneocystostomy: description of technique and outcome in nine dogs.

OBJECTIVE: To report the procedure, postoperative outcome and complications of a new technique for ureteral implantation by means of a three-stitch ureteroneocystostomy in dogs. MATERIALS AND METHODS: Clinical records of dogs requiring ureteral implantation between April 2007 and June 2013 were retrospectively reviewed. Data retrieved included signalment, preoperative biochemistry results, details of the surgical procedure, perioperative and postoperative complications, postoperative biochemistry results and outcome. RESULTS: Nine dogs fulfilled the inclusion criteria. Follow-up times ranged from 10 to 79 months (median 30 months), with 8 of 9 dogs having an excellent long-term outcome and no major postoperative complications. One dog with follicular cystitis as a comorbidity developed obstruction from inflammatory granuloma and required revision surgery. CLINICAL SIGNIFICANCE: The three-stitch technique for ureteral implantation compares favourably to previously documented techniques in terms of outcome and complication rates. Reduced tissue handling and a decreased volume of suture material may be beneficial for healing. The technique is also faster than previously described options, which may be of benefit in unstable patients requiring ureteral implantation due to traumatic injury or rupture.

End-to-end ureteral anastomosis and double-pigtail ureteral stent placement for treatment of iatrogenic ureteral trauma in two dogs.

CASE DESCRIPTION: A 6-month-old spayed female Soft-Coated Wheaten Terrier and 8-month-old spayed female Shih Tzu were referred because of complications related to inadvertent ureteral ligation and transection during recent ovariohysterectomy. CLINICAL FINDINGS: The Soft-Coated Wheaten Terrier had a 2-day history of stranguria and polyuria that began after ovariohysterectomy. Initial examination findings were unremarkable with the exception of high rectal temperature. The Shih Tzu had a 10-day history of pyrexia, vomiting, diarrhea, and stranguria that began after ovariohysterectomy. On examination, the dog had signs of depression; clinicopathologic tests revealed hypoalbuminemia, neutrophilia, lymphocytosis, and monocytosis. Abdominal ultrasonography was performed for both dogs, revealing severe unilateral pyelectasia and hydroureter (proximal portion). TREATMENT AND OUTCOME: Both dogs underwent exploratory celiotomy; ureteral ligation and transection was confirmed. Ventral cystotomy was performed to allow retrograde placement of a double-pigtail ureteral stent into the affected ureter and renal pelvis. End-to-end ureteral anastomosis was performed over the stent with the aid of an operating microscope. Stent position was confirmed via fluoroscopy, and incisions were closed routinely. Dogs continued to have intermittent signs of stranguria until stent removal via cystoscopy 6 or 7 weeks after surgery. Ultrasonographic examination of the urogenital tract was performed 2 or 4 months after surgery, revealing resolution of pyelectasia and hydroureter. CLINICAL RELEVANCE: The surgical technique used provided a viable option for preserving renal function in dogs with focal, iatrogenic ureteral trauma. Use of a ureteral stent facilitated ureteral anastomosis and minimized postoperative complications.

ASSOCIATIONS BETWEEN ULTRASOUND AND CLINICAL FINDINGS IN 87 CATS WITH URETHRAL OBSTRUCTION.

Urethral obstruction is a life-threatening form of feline lower urinary tract disease. Ultrasonographic risk factors for reobstruction have not been previously reported. Purposes of this retrospective cross-sectional study were to describe urinary tract ultrasound findings in cats following acute urethral obstruction and determine whether ultrasound findings were associated with reobstruction. Inclusion criteria were a physical examination and history consistent with urethral obstruction, an abdominal ultrasound including a full evaluation of the urinary system within 24 h of hospitalization, and no cystocentesis prior to ultrasound examination. Medical records for included cats were reviewed and presence of azotemia, hyperkalemia, positive urine culture, and duration of hospitalization were recorded. For medically treated cats with available outcome data, presence of reobstruction was also recorded. Ultrasound images were reviewed and urinary tract characteristics were recorded. A total of 87 cats met inclusion criteria. Common ultrasound findings for the bladder included echogenic urine sediment, bladder wall thickening, pericystic effusion, hyperechoic pericystic fat, and increased urinary echoes; and for the kidneys/ureters included pyelectasia, renomegaly, perirenal effusion, hyperechoic perirenal fat, and ureteral dilation. Six-month postdischarge outcomes were available for 61 medically treated cats and 21 of these cats had reobstruction. No findings were associated with an increased risk of reobstruction. Ultrasonographic perirenal effusion was associated with severe hyperkalemia (P = 0.009, relative risk 5.75, 95% confidence interval [1.54-21.51]). Findings supported the use of ultrasound as an adjunct for treatment planning in cats presented with urethral obstruction but not as a method for predicting risk of reobstruction.

MULTIDETECTOR-ROW COMPUTED TOMOGRAPHIC CHARACTERISTICS OF PRESUMED PREURETERAL VENA CAVA IN CATS.

Preureteral vena cava (circumcaval ureter, retrocaval ureter) occurs in a third of the feline population and has been associated with ureteral strictures in humans. The aim of this retrospective cross-sectional study was to describe the contrast-enhanced multidetector row computed tomographic (MDCT) characteristics of presumed preureteral vena cava in a group of cats. Medical records from two institutions located in different continents were searched from 2010-2013 for cases with complete contrast-enhanced MDCT examinations of the abdomen (i.e. included the entire course of the ureters and prerenal and renal segments of the caudal vena cava) and a diagnosis of preureteral caudal vena cava. For cases meeting inclusion criteria, CT scan data were retrieved and characteristics of the preureteral caudal vena cava were recorded. Presence of concomitant renal or ureteral diseases was also recorded. A total of 272 cats had contrast-enhanced abdominal CT scans during the study period and of these, 68 cats (22.43 ± 4.96%) had a diagnosis of presumed preureteral vena cava. In all affected cats, a "reverse-J ureter" was observed, i.e. a ureter running medially at the level of L4-5, passing dorsally to the caudal vena cava and then exiting ventrally between the caudal vena cava and aorta returning to its normal position. Having a preureteral vena cava resulted in an increased risk for concurrent urinary signs (OR = 3.00; CI: 95%; 1.28-6.99; P = 0.01). Findings supported the use of contrast-enhanced MDCT for characterizing morphology of preureteral vena cava and its relation with ureters in cats.

Bilateral renal dysplasia, hydronephrosis, and hydroureter in a septic neonatal foal.

A Canadian warmblood foal treated for septic polyarthritis was diagnosed with bilateral congenital renal dysplasia, hydronephrosis, and hydroureter at 2 weeks of age based on abdominal ultrasound and postmortem examination. Intermittent abdominal pain throughout the course of treatment was attributed to hydronephrosis and hydroureter.

Dysplasie rénale bilatérale, hydronéphrose et urétérohydrose chez un poulain néonatal septique. Un poulain Warmblood canadien traité pour une polyarthrite septique a été diagnostiqué avec de la dysplasie rénale congénitale bilatérale, de l'hydronéphrose et de l'urétérohydrose à l'âge de 2 semaines en se fondant sur une échographie abdominale et une autopsie. Une douleur abdominale intermittente pendant l'administration du traitement a été attribuée à l'hydronéphrose et à l'urétérohydrose.(Traduit par Isabelle Vallières).

IMAGING DIAGNOSIS--URINARY BLADDER DUPLICATION IN A CAT.

A female kitten presented for chronic, intermittent, antibiotic-responsive urinary incontinence and chronic kidney disease. Abdominal ultrasound identified bilateral pelvic/ureteral dilation and three closely apposed thin-walled fluid-filled structures in the caudal abdomen, extending toward the pelvic inlet. Excretory urography and negative contrast cystography identified contrast medium accumulation from the dilated ureters into two tubular soft tissue masses of the caudal abdomen, with subsequent gradual filling of a more cranially located urinary bladder. A retrograde vaginocystourethrogram identified a normal uterus, normal vagina, and a single urethra continuous with the cranially located urinary bladder. Antemortem diagnosis was suspicious for bilateral ectopic ureteroceles. Postmortem diagnosis, 35 months following initial presentation, determined the fluid-filled masses to have abundant smooth muscle in the wall, including a muscularis mucosa connected by a common ostium, consistent with urinary bladder duplication. Urinary bladder duplication should be included as a differential diagnosis in cats with these clinical and imaging characteristics. In this case, differentiation of ectopic ureterocele from urinary bladder duplication required histological confirmation.

Diagnosis and management of urinary ectopia.

Ectopic ureters are the most common cause of urinary incontinence in young dogs but should be considered as a differential in any incontinent dog for which the history is not known. Ectopic ureters can be diagnosed with excretory urography, fluoroscopic urethrography or ureterography, abdominal ultrasonography, cystoscopy, helical computed tomography, or a combination of these diagnostic procedures. Other congenital abnormalities can also occur in dogs with ectopic ureters, including renal agenesis or dysplasia, hydronephrosis, and/or hydroureter and vestibulovaginal anomalies; therefore, the entire urinary system must be evaluated with ultrasonography if cystoscopy is the only other diagnostic tool used before surgery. Novel surgical techniques and adjunctive medical management have improved the prognosis for dogs with urinary ectopia.

Ectopic ureters in male dogs: review of 16 clinical cases (1999-2007).

Ureteral ectopia is a well-described cause of urinary incontinence in female dogs, but this condition has not been completely characterized in male dogs. Sixteen male dogs with ectopic ureters were evaluated between Jan 1999 and Mar 2007. Male dogs were similar to female dogs with ectopic ureters in terms of breed, presenting complaint, age of onset, and bilateral nature of the ectopia. Diagnosis was made by expert interpretation of imaging techniques such as excretory urography and contrast-enhanced computed tomography (CT). Overall, 11 of 13 dogs that had surgical correction of ectopic ureters were incontinent preoperatively. Urinary continence was restored in 82% of those dogs.

Bilateral ureteropelvic junction stenosis causing hydronephrosis and renal failure in an adult cat.

A 3.5-year-old male neutered cat was presented for investigation of renomegaly appreciated during a routine physical examination. Marked renomegaly due to bilateral hydronephrosis was detected and further testing identified International Renal Interest Society stage 2, non-hypertensive, non-proteinuric chronic kidney disease. Ten months later the cat was evaluated for acute lethargy; severe azotemia with oliguria was documented. Medical therapy failed to result in clinical improvement and the cat was euthanased. Necropsy revealed bilateral marked hydronephrosis secondary to a tortuous proximal ureter consistent with proximal ureteropelvic junction stenosis. This is the first report of this disorder leading to progressive renal failure in a cat.

Ectopic ureters in dogs: clinical features, surgical techniques and outcome.

OBJECTIVE: To compare clinical features of ectopic ureter (EU) in male and female dogs and outcome after neoureterostomy with resection restricted to the intravesical part of the ureter for intramural ectopic ureter (iEU) or of ureteroneocystostomy for extramural ectopic ureter (eEU). STUDY DESIGN: Retrospective case series. ANIMALS: Female dogs (n = 26) with 32 iEU and 8 eEU; male dogs (n = 24) with 25 iEU and 18 eEU. METHODS: Data were collected from medical records (1992-2008). Long-term follow-up information after surgical correction by modified neoureterostomy or ureteroneocystostomy was gathered by owner questionnaire. RESULTS: Median age at first occurrence of UI was significantly lower in females (<2 months) than in males with EU (8 months; P = 0.0015). Bilateral occurrence and an extramural course of the ureter were more common in males (n = 19 and n = 20, respectively) compared with females (14 and 12, respectively), but the outcome of surgical treatment was comparable in both genders. CONCLUSIONS: The prognosis after surgery is fair with a success rate of 72% and a complication rate of 26%. Resection of only the intravesicular ectopic ureter resulted in resolution of incontinence in a high percentage of dogs and thus is an acceptable alternative to removal of the entire ureteral remnant.

Endoscopic placement of ureteral stents for treatment of congenital bilateral ureteral stenosis in a dog.

CASE DESCRIPTION: A 5-year-old 8.6-kg (18.9-lb) spayed female Pug was evaluated because of chronic hematuria and recurrent urinary tract infections. CLINICAL FINDINGS: Excretory urography, ultrasonography, and excretory CT urography were performed. Results indicated that the dog had bilateral hydronephrosis and hydroureter and suspected proximal ureteral stenosis. Retrograde ureteropyelography confirmed the presence of stenosis at the ureteropelvic junction of each ureter, along with a large amount of endoluminal ureteral debris. Clinical findings suggested that the dog had a congenital bilateral anomaly of the upper urinary tract. TREATMENT AND OUTCOME: The dog was anesthetized, and 2 double-pigtail ureteral stents were placed cystoscopically with fluoroscopic guidance for immediate relief of the ureteropelvic junction obstructions. Each stent extended from the left or right renal pelvis to the urinary bladder. The procedures and the patient's recovery from anesthesia were uncomplicated. Continuing improvements in severity of hydronephrosis, hydroureter, and dysuria were evident during routine follow-up examinations at 2, 4, 12, 16, and 45 weeks after stent placement. Over the subsequent 12 months, all clinical signs remained resolved other than a urinary tract infection that was successfully treated with antimicrobials. CLINICAL RELEVANCE: Ureteral stenosis should be considered as a differential diagnosis for hydronephrosis in dogs, particularly when urinary tract calculi or neoplasia is not present. Chronic hematuria and recurrent urinary tract infections can be associated with this condition. Placement of ureteral stents may be a successful treatment option for ameliorization of congenital ureteral obstructions.