Use of a modified Boari flap for the treatment of a proximal ureteral obstruction in a cat

Evaluation of two nephrocystostomy techniques for ureteral bypass in cats

OBJECTIVE

To describe two techniques for nephrocystostomy (NCT) in cats.

STUDY DESIGN

Experimental study.

ANIMALS

Twelve, adult, purpose-bred, cats.

METHODS

A simple NCT (n = 3) or bladder cuff NCT (n = 9) was performed in the right or left kidneys. For simple NCT, an 8F catheter was placed through the caudal pole into the renal pelvis and the bladder was sutured around the catheter. For bladder cuff NCT, a 6 mm defect was removed from the caudal pole and a cuff of bladder mucosa was advanced and sutured into the renal pelvis. A 10F catheter was placed through the defect into the renal pelvis and the bladder wall was sutured around the catheter. Catheters were removed 41-118 days post-surgery. Computed tomography (CT) was performed 25 days after catheter removal for the simple NCT and 30 (n = 6) and 90 (n = 3) days after catheter removal for bladder cuff NCT. Histological evaluation of the nephrocystostomy site was performed.

RESULTS

All simple NCTs became obstructed after catheter removal. All bladder cuff NCTs were patent, and CT revealed contrast flow into the bladder. Hematuria, clot-associated urethral obstruction, catheter dislodgement, and bladder infection occurred variably after surgery. Histological findings consisted of smooth epithelialization of the NCT and degenerative changes in the caudal pole of the kidney.

CONCLUSION

Bladder cuff NCT was feasible in normal cats and remained patent for 90 days. Methods to limit nephrostomy track hemorrhage should be investigated. Degenerative changes may be related to vascular impairment from the bladder cuff sutures.

CLINICAL SIGNIFICANCE

Complete ureteral bypass was possible in cats using only native tissues.

Extravesicular, two-layer, side-to-side ureteroneocystostomy combined with tension-relieving techniques for feline proximal ureteral obstruction: A retrospective study

OBJECTIVE

To describe the surgical technique for extravesicular, two-layer, side-to-side ureteroneocystostomy combined with tension-relieving techniques (ETSUTT) for feline proximal ureteral obstruction and report clinical outcomes.

STUDY DESIGN

Retrospective case series.

ANIMALS

Ten privately-owned cats with ureteral obstruction near the ureteropelvic junction (UPJ).

METHODS

Medical records were retrospectively reviewed for cats with ureteral obstruction close to the UPJ that underwent ETSUTT (2018-2021). The ETSUTT procedure consisted of a modified extravesicular technique (two-layer, side-to-side ureteroneocystostomy) and tension-relieving techniques (renal descensus, ureterocystopexy, and nephrocystopexy).

RESULTS

All cats survived through discharge. In all cats, postoperative blood urea nitrogen and creatinine concentrations were decreased, compared with preoperative concentrations. Perioperative complications included ureteral catheter dislodgement (3), transient pollakiuria (2), and dysuria (1), but no specific treatments were required. Urinary tract infection was observed postoperatively in three of the 10 cats. The median follow-up was 648 days (min-max: 86-1229 days). Seven of the 10 cats were alive without recurrent ureteral obstruction at the end of this retrospective study.

CONCLUSION

The ETSUTT procedure was successfully performed without major complications in cats with ureteral obstruction occurring near the UPJ. Use of ETSUTT provided a fair-to-good, long-term prognosis in cats that were otherwise difficult to manage.

CLINICAL SIGNIFICANCE

This novel procedure, ETSUTT, was feasible, safe, and could be a viable treatment option for feline proximal ureteral obstruction, including the UPJ, especially for obstructions caused by stricture.

Bilateral renal descensus and intravesicular ureteroneocystostomy for treatment of bilateral ureteral ligation and transection that occurred during ovariohysterectomy in two cats

CASE DESCRIPTION

6-month-old and 7-month-old spayed female domestic shorthair cats were referred because of complications associated with inadvertent bilateral ureteral ligation and transection during ovariohysterectomy.

CLINICAL FINDINGS

Both cats had a 1- to 2-day history of lethargy, inappetence, and vomiting. Initial exam findings included lethargy, signs of abdominal pain, anuria, and dehydration. Clinicopathologic testing revealed azotemia and hyperkalemia. Abdominal ultrasonography revealed peritoneal effusion and bilateral pyelectasia in both cats and retroperitoneal effusion in one. Fluid analysis in both cats supported a diagnosis of uroabdomen.

TREATMENT AND OUTCOME

Exploratory celiotomy was performed in both cats, and bilateral ureteral ligation and transection was confirmed. Bilateral renal descensus and ureteroneocystostomy with an intravesicular mucosal apposition technique was successfully performed in both cats. Clinicopathologic evaluation performed 1 day after surgery in one cat and 5 days after surgery in the other revealed complete resolution of azotemia. Ultrasonographic examination of the urogenital tract performed approximately 4 months after surgery in the first cat and 1 month after surgery in the second cat revealed complete resolution of renal pelvic dilation bilaterally.

CLINICAL RELEVANCE

Bilateral intravesicular ureteroneocystostomy in conjunction with bilateral renal descensus was used successfully to treat bilateral ureteral transection that occurred in 2 cats during routine ovariohysterectomy. Limited treatment options currently exist for this serious complication, and euthanasia is often considered. This technique, which relies on the use of the natural surrounding tissues for successful treatment, can offer a potential treatment option to correct this uncommon but devastating complication.

Postoperative outcomes of 12 cats with ureteral obstruction treated with ureteroneocystostomy

OBJECTIVE

To report complications and long-term outcomes of cats with benign ureteral obstruction treated with ureteroneocystostomy and to determine the effects of double pigtail catheter (DPT) placement on postoperative outcomes.

STUDY DESIGN

Retrospective study.

ANIMALS

Twelve client-owned cats with ureteral urolithiasis treated with ureteroneocystostomy.

METHODS

Records were reviewed for signalment, location of the obstruction, diagnostic tests, surgical technique, perioperative complications, long-term measurements of kidney function, and survival. Cats were divided into two groups; in one group, a DPT was placed at the time of ureteroneocystostomy, and, in the other group, a DPT was not placed at the time of ureteroneocystostomy (NDPT).

RESULTS

A DPT was placed in six of 12 cats. The NDPT group included four cats with temporary catheters and two cats with no catheter. Median creatinine concentration decreased from 10.4 mg/dL (range, 1.6-20.3) to 2.2 mg/dL (range, 1.1-3.6) at the time of discharge (P = .015) in all cats. Two cats in the NDPT group required revision surgery for uroabdomen. Eleven cats were discharged from the hospital. Long-term complications (hematuria, pollakiuria, urinary tract infections) were more common in the DPT group (P = .047). Seven cats were alive a median of 329 days (range, 8-1772) after surgery. Median creatinine concentration was 2.0 mg/dL (range, 0.6-6.4) at a median of 157 days (range, 43-1772) after surgery.

CONCLUSION

Ureteroneocystostomy resulted in acceptable long-term outcomes in 11 of 12 cats. The placement of a DPT did not influence the long-term outcome in this small population.

CLINICAL SIGNIFICANCE

Ureteroneocystostomy with or without intraoperative placement of a DPT should be considered to relieve benign ureteral obstructions in cats.