Evaluation of a Transpelvic Sling Procedure With and Without Colposuspension for Treatment of Female Dogs With Refractory Urethral Sphincter Mechanism Incompetence

Objective —To evaluate a sling procedure using a polyester ribbon passed through the obturator foramen, around the urethra, and fixed outside the pelvis for the treatment of female dogs with refractory urethral sphincter mechanism incompetence (USMI). Animals —26 female dogs with USMI that had not improved with medical management. Methods—All dogs underwent a transpelvic sling procedure, and in 13, with a radiographic diagnosis of a pelvic bladder, additional colposuspension was performed. Multichannel urethral pressure profilometry (UPP) and diuresis cystourethrometry (UCM) were performed in all dogs before and in seven dogs 2 to 14 months after surgery. Long-term results of surgery and medical therapy were determined. Results — 13 dogs (50%), 6 of these without additional colposuspension, were continent after surgery and remained continent during a follow-up period of 12 to 36 months (mean, 19 months). Seven, three of which had colposuspension, had improved markedly. Four of these dogs became continent with additional medical therapy. Five dogs did not improve, and three of these were eventually euthanatized. In one dog, the sling was removed after 5 days because of persistent stranguria. Surgery and medical therapy together resulted in continence in 17 dogs (65%) during a follow-up period of 6 to 36 months (mean, 22 months). Postoperative dysuria or stranguria occurred in six dogs, and four of these underwent a colposuspension procedure. Two dogs developed a fistula, 2 and 3 years after surgery. Preoperatively, decreased urethral resistance was suggested by the findings of UPP and UCM in 25 dogs, and an abnormally high compliance was found in 3, detrusor instability in 2, and a low threshold pressure in 1 dog. There was no apparent correlation between these findings and the outcome of surgery. Urethral closure pressures measured after surgery were significantly increased but were still lower than the normal range in all dogs with persistent or recurrent incontinence. Conclusions —A transpelvic sling procedure, with or without additional colposuspension, can be useful in the management of dogs with refractory urinary incontinence. The procedure is not beneficial if it does not increase urethral pressure close to, or within, the normal range.     

Surgical Management of Congenital Urethral Sphincter Mechanism Incompetence in Eight Female Cats and a Bitch

Congenital urethral sphincter mechanism incompetence is a cause of urinary incontinence in female dogs and cats. In some of these animals, urethra hypoplasia is the primary diagnosis, with the urethra being almost absent in some patients. Treatment of this problem can be difficult. This paper describes two techniques for the surgical treatment of eight cats and one dog with severe urethral hypoplasia. In five animals, partial excision of the bladder neck was performed to create a longer "urethra." In the other four, an attempt was made to conserve bladder volume while simultaneously creating a urethra with a bladder neck flap reconstruction technique. One cat was lost to follow-up, but the clinical signs resolved in three cats and the remaining animals improved. Two cats had recurring cystitis, possibly associated with bladder neck diverticula because of uterine horn remnants terminating abnormally in the bladder. The results in this limited series suggest that reconstructive surgery in cases of severe urethral hypoplasia improves continence control.     

Urinary incontinence due to ectopic ureter in a male dog.

Urinary incontinence was associated with an ectopic ureter in a 5-month-old, male Wire Fox Terrier. The dog regained urinary continence after transplantation of the ureter from the urethra into the urinary bladder. Of the 3 reported cases of extopic ureters in male dogs, 2 have been associated with urinary incontinence. These observations do not support the hypothesis that ectopic ureters are more frequently recognized in female than in male dogs because urinary incontinence is more commonly associated with the disorder in female dogs.     

Prostatopexy as a treatment for urethral sphincter mechanism incompetence in male dogs

OBJECTIVES: The incidence of urinary incontinence due to urethral sphincter mechanism incompetence (USMI) in male dogs is relatively rare compared with the incidence in bitches, but the medical management of USMI in male dogs is less rewarding than in bitches. Attempts have been made to manage this condition surgically using either urethral bulking agents such as Teflon or by relocating the intrapelvic bladder neck to an intra-abdominal position by vas deferentopexy. This paper reports the response to prostatopexy in male dogs with USMI. METHODS: The response to prostatopexy was determined in nine severely incontinent male dogs with USMI that were followed up for periods ranging from 10 months to five years (mean 2.3 years). RESULTS: One dog was cured, four were improved, and no improvement in the frequency or degree of urinary incontinence occurred in the remaining four animals. No complications were seen in any of the dogs. CLINICAL SIGNIFICANCE: Prostatopexy may provide a further method of treating male dogs with USMI that do not respond to medical therapy.     

Use of a particulate extracellular matrix bioscaffold for treatment of acquired urinary incontinence in dogs

OBJECTIVE: To evaluate use of a particulate bioscaffold consisting of the extracellular matrix (ECM) of the urinary bladder from pigs for treatment of acquired urinary incontinence in dogs resistant to medical treatment. DESIGN: Case series. ANIMALS: 9 female dogs with acquired urinary incontinence. PROCEDURE: In 6 dogs, 30 mg of particulate ECM in 1.0 mL of a carrier consisting of glycerin and saline 10.9% NaCI) solution was injected into each of 3 equally spaced sites around the circumference of the internal urethral sphincter via an endoscopic technique. In the remaining 3 dogs (control dogs), 1.0 mL of the carrier alone was injected in 3 equally spaced sites around the circumference of the internal urethral sphincter in a similar manner. RESULTS: For dogs treated with the ECM, median duration of urinary continence following treatment was 168 days (range, 84 to 616 days), whereas for the control dogs, median duration of urinary continence following the procedure was 14 days (range, 7 to 31 days). Two of the 3 control dogs were treated with the ECM at the end of the study and were continent for 119 and 252 days. No adverse effects were observed in any dog. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that endoscopically guided injection of particulate ECM into the internal urethral sphincter may be useful for the treatment of acquired urinary incontinence in female dogs.     

Influence of vestibulovaginal stenosis,pelvic bladder,and recessed vulva on response to treatment for clinical signs of lower urinary tract disease in dogs: 38 cases (1990-1999)

OBJECTIVE: To determine influence of vestibulovaginal stenosis, pelvic bladder, and recessed vulva on response to treatment for clinical signs of lower urinary tract disease in dogs. DESIGN: Retrospective study. ANIMALS: 38 spayed female dogs. PROCEDURE: Medical records and client follow-up were reviewed for dogs evaluated via excretory urography because of clinical signs of lower urinary tract disease. Clinical signs, results of radiography, and response to surgical or medical treatment were analyzed. RESULTS: Clinical signs included urinary tract infection (n = 24), urinary incontinence (20), vaginitis (11), pollakiuria or stranguria (10), and perivulvar dermatitis (4). Vaginocystourethrographic findings included vestibulovaginal stenosis (n = 28), pelvic bladder (17), and ureteritis or pyelonephritis (4). Ten dogs had a vestibulovaginal ratio of < 0.20 (severe stenosis), 9 dogs had a ratio of 0.20 to 0.25 (moderate stenosis), 9 dogs had a ratio of 0.26 to 0.35 (mild stenosis), and 10 dogs had a ratio of > 0.35 (anatomically normal). Lower urinary tract infection, incontinence, and pelvic bladder were not associated with response to treatment for recessed vulva. Vestibulovaginal stenosis with a ratio < 0.20 was significantly associated negatively with response to treatment. Dogs without severe vestibulovaginal stenosis that received vulvoplasty for a recessed vulva responded well to treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Vestibulovaginal stenosis is likely an important factor in dogs with vestibulovaginal ratio < 0.20. Vaginectomy or resection and anastomosis should be considered in dogs with severe vestibulovaginal stenosis and signs of lower urinary tract disease.     

Surgical Treatment of Male Dogs With Urinary Incontinence Due to Urethral Sphincter Mechanism Incompetence

A modified technique for fixation of the deferent ducts to the abdominal wall as a therapy for urinary incontinence caused by urethral sphincter mechanism incompetence (USMI) in male dogs is described, and the results in seven dogs are reported. The goal of this treatment was to achieve an effect similar to colposuspension in female dogs with USMI. An increase in urethral length of an average of 28 mm was obtained (range, 5 to 50 mm, measured radiographically). Preoperatively, the neck of the bladder was located intrapelvically in five of seven dogs. Postoperatively, the neck of the bladder was located intra-abdominally, near the caudo-ventral abdominal wall, in all dogs. After a follow-up period of 12 to 49 months, the response to surgery, based on lack of or decrease of incontinence, was excellent in three dogs, good in another three, and poor in one dog.     

Pelvic bladder in dogs without urinary incontinence

Double-contrast cystography was performed simultaneously with cystometrography in 6 male and 6 female dogs. All dogs were continent, and results of urinalyses were normal. Initial radiographs were made following intravesical infusion of 0.88 ml of positive contrast medium/kg of body weight. Additional radiographs were made during infusion of CO2. The last radiographs were made at the time of detrusor reflex (11 dogs) or when intravesical pressure reached 50 cm H2O (1 female). An average of 34% (range, 11% to 67%) of bladder length was within the pelvic canal when only the positive contrast medium was infused into the bladders. By the end of CO2 infusion, the bladder neck was more cranially located in 5 of 6 males and in 5 of 6 females. On the last radiographs made, an average of 19% (range, 10% to 35%) of bladder length was within the pelvic canal in 3 of 6 males and in 4 of 6 females. The bladder neck was rounded in 10 of 12 dogs. Thus, it was concluded that previous reports associating pelvic urinary bladder with urinary incontinence and other urologic abnormalities are questionable.     

Urologic disorders of the geriatric dog

Disorders of the urinary system are common in geriatric dogs. Common urinary disorders that are seen in older dogs include chronic renal failure, urinary incontinence, bladder tumors, and prostate problems. Therapy for chronic renal failure is aimed at both slowing the progression of the disease and ameliorating the signs of uremia. Therapeutic recommendations for the conservative medical management of chronic renal failure include reducing dietary protein, moderately reducing salt intake, maintaining normal serum phosphorus levels, providing free access to water, avoiding stress, supplementing water soluble vitamins, using anabolic steroids to treat the anemia of chronic renal failure, treating acidosis, and controlling hypocalcemia. Urinary incontinence can often be controlled or eliminated. The appropriate approach to management of this disorder is to identify and remove specific causes. Common causes of urinary incontinence are urethral incompetence, urinary tract infection, and polyuria and polydypsia. Bladder tumors are, fortunately, not a common tumor of dogs, but are more common in geriatric dogs than in the young. The most common bladder tumor is the transitional cell carcinoma. Therapy for this tumor is usually palliative because of its malignant nature and because it is usually located in the neck of the bladder. Its location in the bladder often makes it impossible to resect the tumor completely without removing the entire bladder and diverting the ureters. New chemotherapeutic modalities are being evaluated that may increase life expectancy after diagnosis and, therefore, improve prognosis. Prostate disease is also seen in older dogs. Types of prostate abnormalities seen in dogs include prostatic hyperplasia, cysts, abscesses, acute and chronic infection, and neoplasia. The institution of proper therapy requires an accurate diagnosis; neutering is often recommended as a part of therapy regardless of the type of prostatic disease present.     

Bilateral Ureteroileostomy and Perineal Urinary Diversion in Dogs

The urinary bladder was excised, and the ureters were implanted into an isolated segment of distal jejunum and ileum in three experimental dogs. The isolated bowel loop was drawn through the pelvic canal within the external anal sphincter to exit ventral to the anus. The dogs were evaluated for urinary continence, urinary tract infection, and renal function for up to 6 months postoperatively.
Urinary continence did not return. Continuous urine leakage caused perineal scalding. The cutaneous openings of the isolated bowel loops developed strictures. Serum creatinine and urea nitrogen concentrations did not increase. Excretory urography and retrograde radiographic studies of the bowel loop were performed periodically. Unilateral hydronephrosis was observed in two dogs 2 weeks postoperatively. The remainder of the excretory urograms were normal. Ureteral reflux was observed commonly on retrograde contrast studies. Positive bacterial cultures were obtained from all bowel loops and kidneys at necropsy. Alpha-streptococcus, Escherichia coli , and Proteus spp. were isolated most frequently. Mild pyelitis was seen in histopathologic examination of the kidneys after necropsy. Urothelium replaced bowel mucosa near the site of ureteral implantation.
This method of urinary diversion is not satisfactory for clinical use.     

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.     

Treatment of urinary incontinence in bitches by endoscopic injection of glutaraldehyde cross-linked collagen

Thirty-two spayed bitches with urinary incontinence due to urethral sphincter incompetence, non-responsive to phenylpropanolamine administration, were treated by urethral submucosal injection of glutaraldehyde cross-linked collagen. Urinary incontinence resolved after a single injection in 19 of the bitches. Additional medication with phenylpropanolamine was necessary in five of these dogs, however. Of the 13 bitches that remained incontinent, the injections were repeated in nine. This resulted in a return to continence in five dogs, although two of these required additional medication for complete continence. The cure rate due to collagen injections alone is 53 per cent (17 of the 32 cases). A total of 41 injections were performed and no postoperative complications were observed.     

Clinical and radiographic findings compared with urodynamic findings in neutered female dogs with refractory urinary incontinence.

Possible correlations were investigated between the clinical and urodynamic findings in 77 neutered female dogs with urinary incontinence refractory to standard medical management. The clinical data used in the analysis were age, bodyweight, breed, the characteristics of the dribbling of urine and whether it developed before or after neutering, the type of response to previous treatments, signs of polyuria/polydipsia, and the results of urinalysis and culture. In 50 of the dogs, a standardised contrast radiographic examination was made to locate the neck of the bladder and to assess the morphology of the bladder. These findings were analysed for their correlation with the results of multichannel urethral pressure profilometry and diuresis cysto-urethrometry. Logistic regression analysis revealed that neither the clinical nor the radiographic findings could predict any of the abnormal urodynamic findings. Functional abnormalities of the bladder, such as a low compliance, detrusor instability, or a low bladder capacity may therefore be particularly difficult to detect in dogs with urinary incontinence.     

A technique for resection of invasive tumors involving the trigone area of the bladder in dogs: preliminary results in two dogs

Objective— To describe a surgical technique for resection of the entire bladder neck, including the trigone and proximal urethra in dogs with invasive tumors causing life-threatening urinary tract obstruction.
Study Design— Clinical case reports.
Animals— Dogs (n=2) with bladder tumors.
Methods— Circumferential excision of the bladder neck and proximal urethra with preservation of the neurovascular pedicles was performed to remove a rhabdomyosarcoma (dog 1) and a transitional cell carcinoma (dog 2) involving the trigone and bladder neck that were causing urinary tract obstruction. Reconstruction of the bladder and proximal urethra included bilateral ureteroneocystostomy. Adjuvant chemotherapy was administered postoperatively to both dogs.
Results— Postoperatively, dogs 1 and 2 were continent after 7 and 17 days, respectively, and regained normal urinary function after resolution of a transient pollakiuria. Dog 1 had no evidence of local or regional recurrence; however, a large solitary pulmonary metastatic lesion was diagnosed 8 months later. The dog was euthanatized despite a lack of clinical signs. Dog 2 had at least 1 metastatic lesion in the abdominal wall 6 months later and was euthanatized at 580 days because of renal failure.
Conclusion— En-bloc removal of the bladder neck and proximal urethra with preservation of the dorsal vascular and nervous pedicles, although a technically challenging procedure, can be performed without associated urinary incontinence or bladder wall necrosis.
Clinical Relevance— In dogs with invasive bladder tumors causing life-threatening urinary tract obstruction, resection of the bladder neck and proximal urethra should be considered as a promising surgical alternative to urinary diversion.     

Computed tomographic features of urinary bladder torsion in two dogs

Urinary bladder torsion is rare in dogs. It is characterised by rotation of the organ along its longitudinal axis and is potentially life‐threatening because of urinary flow obstruction with subsequent urine retention, hydroureter, hydronephrosis and azotaemia. This report describes the computed tomographic features of urinary bladder torsion in two dogs. In both cases, the hallmark indicative of torsion was the “whirl sign,” originating from the twisted pelvic urethra and urinary bladder neck encircling the ureters, blood vessels and bladder ligaments in a characteristic spiral pattern. The imaging features correlated well with surgical findings, demonstrating high sensitivity of computed tomography in the preoperative diagnosis of urinary bladder torsion.     

POSITIVE CONTRAST RETROGRADE URETHROGRAPHY: A USEFUL PROCEDURE FOR EVALUATING URETHRAL DISORDERS IN THE DOG

Positive contrast retrograde urethrography proved to be a useful and relatively simple technic for the evaluation of lower urinary tract disorders in the dog. The case histories of 12 dogs with such disorders were used to illustrate the role of positive contrast retrograde urethrography in the evaluation of urethral and urinary bladder integrity after caudal abdominal and pelvic trauma, and in the investigation of incontinence, stranguria, dysuria, and hematuria.     

Long-Term Efficacy of a Percutaneously Adjustable Hydraulic Urethral Sphincter for Treatment of Urinary Incontinence in Four Dogs

Objective— To evaluate the efficacy of a surgically placed, static hydraulic urethral sphincter (SHUS) for treatment of urethral sphincter mechanism incompetency (USMI).
Study Design— Prospective study.
Animals— Spayed female dogs (n=4) with acquired USMI.
Methods— Urinary incontinence was assessed using a subjective continence score before and after implantation of an SHUS on the proximal urethra via ventral median celiotomy. Dogs were assessed for urinary continence, urinary tract infections, and implant-associated complications for 30 months. Residual incontinence was treated with percutaneous inflation of the SHUS with sterile saline solution through a biocompatible subcutaneous administration port.
Results— At last follow-up (26–30 months after surgery), continence scores improved from a median preoperative score of 3/10 to a median postoperative score of 10. One dog developed wound drainage over the subcutaneously placed administration port but remained continent after port removal. Three occluders were percutaneously filled with additional saline (median, 0.18 mL; mean, 0.16 mL) to improve continence after surgery.
Conclusions— Application and adjustment of an SHUS provided sustained improvements in continence score in all dogs.
Clinical Relevance— In this pilot study, 3 of 4 dogs with hydraulic urethral sphincter implantation had successful percutaneous adjustment and maintained improved continence scores for 2 years after surgery. Continence was maintained in the 4th dog even after administration port removal. Based on this pilot study, the SHUS warrants further clinical evaluation for treatment of dogs with USMI unresponsive to medical management.     

Urodynamic testing in the diagnosis of small animal micturition disorders

Urodynamic testing provides a quantitative assessment of the function of the small animal lower urinary tract. Most commonly these techniques are utilized to assess urethral tone (urethral pressure profile or UPP) and bladder detrusor muscle function (cystometrogram or CMG). A UPP may be indicated in cases of canine and feline micturition disorders. Examples include suspected primary sphincter mechanism incontinence (PSMI), ureteral ectopia, other congenital abnormalities, suspected neurological disorders, and mechanical or functional urethral obstruction. A UPP can be performed effectively utilizing human dedicated equipment. A CMG may be indicated to assess detrusor function in all of the above cases as well as cases of suspected atonic or infiltrated urinary bladder. This procedure can also be performed using the same human equipment. These tests are useful not only in providing an accurate diagnosis, but also in providing a sensitive prognostic indicator for clinical outcome of micturition disorders with and without pharmacological or surgical therapy. A leak pressure point may also be established in dogs with urinary incontinence, and may be even more sensitive than a UPP to predict clinical incontinence in some cases.     

Retrospective evaluation of urethral bovine cross-linked collagen implantation for treatment of urinary incontinence in female dogs

Background: Transurethral collagen injections are an alternative treatment for canine urinary incontinence. There is controversy regarding the long‐term effectiveness of collagen and the impact urethral coaptation and injection site have on outcome. Hypothesis/Objectives: To evaluate outcome and client satisfaction after urethral collagen injections, and correlation between degree of urethral coaptation and collagen placement with outcome. Animals: Thirty‐six procedures on 31 dogs, 10 with ureteral ectopia. Methods: Retrospective review of records and video evaluation of injection procedures. Follow‐up communication with owners was performed between 1 and 56 months after bovine cross‐linked collagen implantation to evaluate duration of continence, need for additional medical therapy, and owner satisfaction. Continence score was evaluated before and after the procedure, and after additional medical therapy, if needed. Injection location and degree of urethral coaptation was assessed with respect to duration of continence. Results: Dogs had a significant increase in continence score after the procedure. Mean (SD) duration of continence in dogs without addition of medication was 16.4 (15.2) months, and 5.2 (4.3) months in dogs needing additional medical therapy. No significant difference was found with respect to degree of coaptation. Median client satisfaction with the procedure was 100%. Conclusions and Clinical Importance: Transurethral collagen implantation may be a viable option for treatment of female dogs with urethral sphincter mechanism incompetence, particularly after medical failure. Duration and degree of improvement are variable. Client satisfaction was excellent despite lack of complete continence in some dogs, and highlights the importance of discussing outcome expectations with owners.