Modified endoluminal ureteral stenting for the management of proximal ureteral obstruction in two cats.

Case series summary: Two cases of placement of modified endoluminal ureteral stents are described, for revision of a subcutaneous ureteral bypass (SUB) and for primary treatment of obstructive ureterolithiasis. Modified endoluminal stents were inserted through the ureterotomy, anchored in the renal pelvis with a single pigtail and shortened to a length sufficient to span the proximal ureter and ureterotomy site. Relevance and novel information: The advantages of this approach as a surgical option for feline obstructive ureterolithiasis are demonstrated, including the avoidance of disruption, or bypass, of the ureterovesicular junction, minimisation of implanted foreign material and avoidance of intravesicular stent mass, maintenance of the physiological route of urine flow, including preservation of active distal ureteral function, and limitation of the potential complications of ureterotomy. The clinical efficacy of this adaptation of the previously published endoluminal stenting technique is demonstrated with its applicability de novo and in the revision of other stenting procedures.

Successful Treatment of Ureteral Obstructive Lithiasis by Ureterotomy in a Domestic Hen.

A 2-year-old domestic hen was presented for a 15-day history of intermittent left leg lameness. The owners also observed a decrease in egg quality during that period. Physical examination of the bird revealed a generalized weakness with a flattened pale comb. Neurological evaluation of the left leg found a proprioceptive deficit with no loss of pain sensitivity. Whole body radiographic images showed a marked reduction of abdominal detail, a large amount of "grit" (mineral opacity) in the ventriculus, intestinal dilation, and a metallic foreign body (nail) in the digestive tract. Abnormal results from a plasma biochemistry panel were hypercalcemia, hypertriglyceridemia, hyperglobulinemia, hypophosphatemia, increased creatine kinase, and decreased uric acid. After initial stabilization of the patient, a computed tomographic scan was obtained, which revealed multiple right-sided ureteral calculi, the largest of which measured 10 mm in diameter, and changes compatible with cystic right renal nephrosis. Suspected compensatory enlargement of the left kidney was also observed. Considering the renal lesion and associated neurological limb impairment, surgery was recommended and approved by the owner. A right lateral approach was used for the coeliotomy, and a ureterotomy was performed to remove all calculi. Analysis of the ureteral stones confirmed they were 100% uric acid salts. The hen fully recovered left leg function 1 week postsurgery. Urolithiasis is well described in hens, but surgical treatment is uncommon. This report describes the successful removal of ureteral stones by ureterotomy in a domestic hen.

Current Concepts in Urinary Surgery.

Management of canine and feline ureteral obstructions and urinary incontinence can be both controversial and frustrating. There has been a movement toward minimally invasive procedures, which in certain cases, can be used to both confirm the diagnosis as well as treat the condition. This chapter focuses on the advancements in urologic surgery associated with ureteral obstruction and urinary incontinence with primary focus on ureteral stenting, subcutaneous ureteral bypass systems, transurethral bulking agents, and hydraulic occluders.

Subcutaneous ureteral bypass device placement with intraoperative ultrasound guidance, with or without microsurgical ureterotomy, in 24 cats.

OBJECTIVES: The aim of this study was to describe a method of subcutaneous ureteral bypass (SUB) device placement with intraoperative ultrasound guidance, with or without microsurgical ureterotomy, for the treatment of benign ureteral obstruction(s) in cats. A secondary aim was to describe the complications and outcomes in our population, and compare the two groups with and without ureterotomy. METHODS: The medical records of cats with benign ureteral obstruction(s) treated with SUB device placement with intraoperative ultrasound guidance between April 2013 and June 2018 were reviewed. RESULTS: Twenty-four cats with 30 obstructed ureters had a SUB device placement with intraoperative ultrasound guidance in 26 surgeries. A microsurgical ureterotomy was performed in 14/26 surgeries. Median age was 10.07 years (range 4-16.6). Eleven of 24 cats (46%) had a previous history of chronic kidney disease (CKD). All cats, including two patients with minimal pelvic dilation (⩽4 mm), had a successful intrapelvic placement of the SUB device. Median survival time was 1555 days (4.25 years); this was not significantly different between the two groups (P = 0.4494). Stone analysis and bacterial culture, where available for review, revealed calcium oxalate in 12/12 and a negative culture in 6/7. The ureterotomy significantly prolonged the procedure duration (180 vs 125 mins) without significantly decreasing the short- and long-term complications (P = 0.1588 and P = 0.2921, respectively), or the survival time (P = 0.8437). CONCLUSIONS AND RELEVANCE: SUB device placement with intraoperative ultrasound guidance is an effective alternative for the treatment of ureteral obstruction. Ultrasound guidance may be a more accessible option when a trained veterinarian does not have access to fluoroscopy. Microsurgical ureterotomy did not show any advantage and prolonged the anesthesia. Our median survival time emphasizes a good outcome of SUB device placement, even in cats with a previous history of CKD.

Bilateral ureterolithiasis in a 7-month-old cat / Ureterolitíase bilateral em um gato de sete meses de idade

ABSTRACT: Feline ureteral obstruction can have several causes; however, ureterolithiasis has been increasing in occurrence. The restriction of urinary flow induced by the obstruction has harmful consequences to the body and can lead to acute renal failure. Calcium oxalate ureterolithiasis is reported in older cats, aged mean 12 years old. A case of bilateral ureteral obstruction in a 7-month-old mixed breed cat is described in this report. Imaging tests such as abdominal ultrasonography, radiography and excretory urography were performed to determine the diagnosis. The surgical procedure of bilateral ureterotomy was then performed, which allowed the improvement of the urinary flow of both kidneys and the resolution of clinical signs caused by uremia. The quantitative analysis of both uroliths revealed the composition of 100% monohydrate calcium oxalate. Calcium oxalate stones can also cause ureteral obstruction in young cats; although, are less common in this age. When conservative treatment fails, surgical intervention becomes necessary for the rapid return of renal function. To author's knowledge this is the first report of a ureterolithiasis caused by calcium oxalate in a young cat.

RESUMO: A obstrução ureteral em gatos pode ter diversas causas, entretanto, a ureterolitíase vem apresentando um aumento na sua ocorrência. A restrição do fluxo urinário induzida pela obstrução traz consequências graves ao organismo, podendo levar a insuficiência renal aguda. A ureterolitíase por cálculos de oxalato de cálcio é relatada em gatos mais velhos, com média de idade de 12 anos. Um caso de obstrução ureteral bilateral em um gato, SRD, com sete meses de idade é descrito nesse relato. Exames de imagem, como ultrassonografia e radiografia abdominais e urografia excretora, foram realizados para confirmar o diagnóstico. O procedimento cirúrgico de ureterotomia bilateral foi então realizado, permitindo a melhora do fluxo urinário de ambos os rins e dos sinais clínicos de uremia. A análise quantitativa de ambos os urólitos revelou a composição de 100% oxalato de cálcio monohidratado. Cálculos de oxalato de cálcio são um diagnóstico diferencial para obstrução ureteral também em gatos jovens, apesar de serem menos comuns. Quando há falha no tratamento conservador, a intervenção cirúrgica torna-se necessária para o rápido restabelecimento e preservação da função renal. No conhecimento dos autores, esse é o primeiro relato de ureterolitíase causada por oxalato de cálcio em um gato jovem.

Retrocaval ureter associated with cryptorchidism: A case report and review of literature.

We report an incidentally diagnosed retrocaval ureter in a 14-year-old boy, while evaluating for right-sided hydronephrosis associated with cryptorchidism. Therefore, we suggest that any significant right-sided hydronephrosis associated with cryptorchidism may require investigations to exclude this rare anomaly.

A giant ureteric calculus.

Ureteric stones are usually small and symptomatic. We present a case of a 35-year old female who presented with minimally symptomatic right distal ureteric calculus with proximal hydroureteronephrosis. Laparoscopic right ureterolithotomy was performed and a giant ureteric calculus measuring 11 cm Χ 1.5 cm, weighing 40 g was retrieved.

Primary obstructive megaureter: cutting balloon endo-ureterotomy.

OBJECTIVE: In this video we will demonstrate endo-ureterotomy using a cutting balloon for vesico-ureteric junction (VUJ) dilatation and stenting of the primary obstructive megaureter. METHOD: For the technique, a 0.014 inch guide-wire is endoscopically inserted through the VUJ and allowed to curl in the megaureter. A 3 mm atherotome-bladed cutting balloon is inflated with iohexol contrast solution. Under fluoroscopy or cystoscopically, the stenotic VUJ segment is observed to open and post-dilated with a 4 mm simple balloon before JJ stent placement for six weeks. RESULTS: This video demonstrates the equipment and technique of VUJ endo-ureterotomy using a cutting balloon and stenting of the primary obstructive megaureter. CONCLUSION: Where intervention for the primary obstructive megaureter is indicated, we propose VUJ endo-ureterotomy as the first line treatment.