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.     

Evaluation of long-term effects of endoscopic injection of collagen into the urethral submucosa for treatment of urethral sphincter incompetence in female dogs: 40 cases (1993-2000)

OBJECTIVE: To evaluate long-term success of endoscopic injection of collagen into the urethral submucosa in female dogs with urinary incontinence caused by urethral sphincter incompetence. DESIGN: Retrospective study. ANIMALS: 40 incontinent female dogs. PROCEDURE: Medical records were reviewed for outcome and other results for dogs in which a cystoscope was passed into the urethra for deposition of 3 collagen deposits into the submucosa. RESULTS: 27 (68%) dogs were continent for 1 to 64 months (mean, 17 months) after the collagen injection. In another 10 dogs, incontinence improved and in 6 of these dogs, full continence was regained with administration of additional medication. In 3 dogs, incontinence was unchanged. As long as 12 months after injection, there was a deterioration in the initial result in 16 dogs, after which their condition stabilized. Mild and transient adverse effects developed in 6 (15%) dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Long-term success of endoscopic injection of collagen was satisfactory. Relapse of incontinence might be caused by flattening of the collagen deposits rather than resorption of the collagen.     

Treatment of urinary incontinence in dogs by endoscopic injection of Teflon

Twenty-two dogs with urethral sphincter incompetence, nonresponsive to phenylpropanolamine administration, were treated by urethral submucosal injection of Teflon. Urinary continence was achieved in all dogs for at least 2 months. Urinary incontinence recurred in 14 dogs (64%) and was controlled by a second Teflon injection in 11 of 12 dogs (92%). Minor complications included transient stranguria, with or without hematuria, after 4 of 35 injection procedures. One dog had temporary partial urethral obstruction after treatment.     

Cystourethropexy to Correct Refractory Urinary Incontinence Due to Urethral Sphincter Mechanism Incompetence Preliminary Results in Ten Bitches

Cystourethropexy was performed in 10 bitches with refractory urinary incontinence due to urethral sphincter mechanism incompetence. All animals had an abnormally shaped vesico-urethral junction. The bladder neck was located in the pelvic canal in nine dogs (pelvic bladder). Surgery alone restored urinary continence in two cases and markedly improved incontinence in two cases. Surgery combined with medical therapy (phenylpropanolamine, 1.5 mg/kg orally once or twice a day, using a sustained-action preparation) restored urinary continence in four cases and markedly improved continence in one case. Surgery, with medical therapy, was completely ineffective in one case. No major complications were encountered in any dogs. In four cases, histopathologic evaluation of the dorsal bladder wall and neck revealed the presence of a single, perinuclear, clear vacuole in the cytoplasm of smooth muscle fibers. Electron microscopic examination showed that the vacuoles represented a dilatation of normal membrane organelles. Such abnormalities have the potential to alter the smooth muscle motility. This study indicates that cystourethropexy alone restored urinary continence only temporarily in the majority of the patients. The significance and frequency of the histopathologic findings requires further investigation.     

Efficacy, tolerance and acceptability of Incontex in spayed bitches with urinary incontinence

A clinical study about efficacy and acceptance of Incontex in spayed bitches with urinary incontinence was performed. In a randomised, double-blinded study the efficacy and acceptance of Incontex (Dr. E. Gr?ub AG, Bern, Schweiz) in bitches with urethral sphincter incompetence due to spaying was evaluated under field conditions. The active ingredient of the Incontex Syrup is phenylpropanolamine (PPA), an alpha1-adrenergic agonist. The study was performed using 24 spayed, incontinent bitches. Over a first period of treatment of 30 days the bitches received either Incontex, at 1.5 mg/kg twice per day, or a placebo. In the second period of 30 days all 24 bitches were treated with Incontex at the recommended dose. Any changes in the incontinence compared with the situation before the study were evaluated. RESULTS: Of 24 bitches 21 (88%) became continent and in 2 bitches (8%) urinary incontinence improved. In only 1 bitch (4%) the medication did have no effect. Five bitches (21%) showed side effects. The acceptance of Incontex was good. CONCLUSION AND CLINICAL RELEVANCE: Incontex can be recommended as an efficient and well-tolerated medication for the treatment of bitches with urinary incontinence after spaying. The oral application of 1.5mg/kg BW phenylpropanolamine twice daily has been approved.     

Clinical evaluation of a single daily dose of phenylpropanolamine in the treatment of urethral sphincter mechanism incompetence in the bitch

The objective of this retrospective study was to determine the efficacy of a single daily oral dose of phenylpropanolamine (PPA) in the treatment of urethral sphincter mechanism incompetence (USMI) in bitches. Nine bitches diagnosed with USMI were treated with a single daily dose [1.5 mg/kg body weight (BW)] of PPA for at least 1 month. Urethral pressure profiles (UPP) were performed in 7 dogs before treatment and repeated in 4 of them after treatment. Treatment with PPA resulted in long-term continence in 8/9 bitches. One dog did not respond to PPA and was treated surgically later. Recheck UPPs showed a significant increase in maximal urethral closure pressure in the 4 bitches after treatment with PPA compared to before treatment. In conclusion, long-term continence can be achieved in bitches affected with USMI after administration of a single daily dose of PPA (1.5 mg/kg BW).     

Treatment of urethral sphincter mechanism incompetence in 11 bitches with a sustained-release formulation of phenylpropanolamine hydrochloride

Between 1995 and 1999, urethral sphincter mechanism incompetence was diagnosed in 11 bitches. They had been treated with phenylpropanolamine hydrochloride at the recommended dose rate, but had shown no response or had become refractory to treatment. They were treated with phenylpropanolamine hydrochloride in a sustained-release formulation combined with diphenylpyraline hydrochloride. The urinary incontinence resolved fully in six of the bitches, two of which remained continent after the treatment was withdrawn; two showed a marked improvement on daily treatment, but the other three bitches failed to respond and underwent colposuspension.     

Phenylpropanolamine: an alpha-adrenergic agent for the management of urinary incontinence in the bitch associated with urethral sphincter mechanism incompetence

Ten bitches with urinary incontinence due to incompetence of the urethral sphincter mechanism were treated with phenylpropanolamine hydrochloride at a dose of either 1 mg/kg orally three times daily or 2 mg/kg orally once daily in a prolonged release formulation. The signs of incontinence resolved in all the bitches, and improvements were maintained over periods ranging from one to more than two years, except in one bitch which became refractory to treatment after three months. One bitch which was inadvertently treated at a dose rate of 2.5 mg/kg showed signs of lethargy and inappetence but returned to normal when the dose rate was reduced.     

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.     

Clinical response and urethral pressure profile changes after phenylpropanolamine in dogs with primary sphincter incompetence

Based on clinical response, urethral pressure profile changes, and lack of side effects, phenylpropanolamine was effective and safe in treating dogs with primary sphincter incompetence. Primary sphincter incompetence was diagnosed in 11 female and 8 male dogs with urinary incontinence. Urodynamics of the dogs were assessed, using a combined urethral pressure profile and urethral sphincter electromyography. Male and female dogs had significantly (P less than 0.05) lower maximal urethral closure pressures, when compared with clinically normally dogs (36.91 +/- 8.20 cm of H2O vs 79.72 +/- 4.61 cm of H2O for female dogs and 48.63 +/- 8.68 cm of H2O vs 99.77 +/- 11.71 cm of H2O for male dogs). After treatment with phenylpropanolamine, there was a significant increase in maximal urethral closure pressure in both sexes to within normal range (77.73 +/- 8.70 cm of H2O in females and 92.50 +/- 14.60 cm of H2O in males). Electromyographic activity was normal before and after treatment. Urinary incontinence resolved clinically in all but 1 male and 1 female dog; however, the condition in these 2 dogs improved considerably. Minimal side effects were seen clinically. Mean arterial blood pressure was not altered by treatment. Plasma estrogen and testosterone concentrations in 8 female dogs were not different from those in continent female dogs. The incontinence in these dogs was considered a sphincter incompetence rather than estrogen responsive.     

Urodynamic and morphologic changes in the lower portion of the urogenital tract after administration of estriol alone and in combination with phenylpropanolamine in sexually intact and spayed female dogs

OBJECTIVE: To compare the urodynamic and morphologic effects of the administration of estriol alone and in combination with phenylpropanolamine on the lower portion of the urogenital tract in female dogs. ANIMALS: 3 sexually intact and 3 spayed female Beagles without urinary incontinence. PROCEDURE: Dogs received estriol (2 mg, PO) once daily for 7 days followed by estriol (2 mg, PO) and phenylpropanolamine (1.5 mg/kg, PO) once daily for 7 days. Urethral pressure profilometry, diuresis cystometry, and vaginourethrography were performed before treatment (day 0) and at days 7 and 14. The maximum urethral pressure (MUP) and closure pressure (MUCP), urethral functional and anatomic profile lengths, integrated pressure (IP), plateau, distance before MUP, maximum meatus pressure, threshold pressure, threshold volume, compliance, urethral length, and vaginal length and width were measured. RESULTS: Before treatment, no urodynamic differences were observed between the 2 groups; however, vaginal length and width were significantly shorter in spayed dogs. Compared with day 0 values, estriol treatment significantly increased MUP, MUCP, and IP values at day 7, but at day 14, this effect decreased despite phenylpropanolamine administration. No morphologic changes from baseline were detected after either treatment in any dog. CONCLUSIONS AND CLINICAL RELEVANCE: Data suggest that estriol mainly acts on the urethral sphincter mechanism by increasing urethral resistance in sexually intact and spayed female dogs without urinary incontinence. Administration of estriol and phenylpropanolamine did not increase the urethral resistance more than estriol alone. The urodynamic effects of estriol in female dogs with urinary incontinence remain to be elucidated.     

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.     

Vaginourethroplasty for Treatment of Urethral Obstruction in the Bitch

Vaginourethroplasty was performed in six bitches with infiltrative, obstructive urethral disease. The initial clinical signs included dysuria, hematuria, pollakiuria, and stranguria. Diagnosis was based on the clinical signs, plain radiography and contrast vagino-urethrogram examination, and urethral biopsy. Five dogs were diagnosed as having urethral neoplasia; the sixth dog had granulomatous urethritis. In all six dogs, up to 50% of the urethra and the urethral tubercle were resected to ensure adequate surgical margins. One dog was euthanatized 4 months after surgery for recurrence of a transitional cell carcinoma at the surgical site. Long-term resolution of the problem (minimum of 12 months) was achieved in the other five dogs. The frequency of serious complications, including urinary incontinence and ascending lower urinary tract infections, was low.     

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.     

Ureteral ectopia and urethral sphincter mechanism incompetence: an update on diagnosis and management options

The two leading causes of urinary incontinence in dogs are ureteral ectopia in juveniles and urethral sphincter mechanism incompetence in adults. While the accuracy of diagnosis of ectopic ureters has improved due to increased use of CT and/or cystoscopy, the diagnosis of urethral sphincter mechanism incompetence largely remains one of exclusion. New treatment options have been developed for both conditions, which have reduced morbidity and mortality, although the rate of long‐term urinary continence has not significantly improved for either and neither has our understanding of the pathophysiology behind these failures. This review provides updates on the management of both of these conditions, with discussion of controversial areas and thoughts for future directions.     

Urethropexy for the management of urethral sphincter mechanism incompetence in the bitch

Urethropexy was performed on 100 bitches for the management of urethral sphincter mechanism incompetence (SMI). The dogs ranged in age from 12 months to nine years (mean 4.5 years). Diagnosis of the condition was based upon clinical, laboratory and contrast radiographic examinations, and clinical response to medical management. In all bitches, incontinence developed in the adult individual and in the majority (89 bitches) after spaying. Radiographic findings were unremarkable in 22 bitches, apart from the presence of an intrapelvic bladder neck. Follow-up periods ranged from 12 months to seven years (mean 2.9 years). Fifty-six bitches were completely cured by surgery, 27 became less incontinent and 17 either failed to respond (nine animals) or showed an initial improvement in urinary function, but then relapsed (eight animals). Nine of these 17 animals underwent a second urethropexy procedure, resulting in a cure in six and an improvement in three cases (follow-up 12 to 41 months, mean 22.2 months). A deterioration in the response rate was observed over time. Postoperative complications were seen in 21 bitches and included an increased frequency of micturition (14 bitches), dysuria (six bitches) and anuria (three bitches).     

Transobturator vaginal tape inside out for treatment of urethral sphincter mechanism incompetence: preliminary results in 7 female dogs

Objectives: To evaluate the clinical efficacy of the transobturator vaginal tape inside‐out (TVT‐O) in incontinent female dogs affected with urethral sphincter mechanism incompetence (USMI) and to determine its urodynamic and morphologic effects. Study Design: Case series. Animals: Incontinent spayed female dogs (n=7). Methods: TVT‐O tape was inserted in 7 incontinent female dogs diagnosed with USMI. Urethral pressure profilometry (UPP) and vaginourethrograms were performed preoperatively, and 1 and 3 months postoperatively. Clinical efficacy of the technique was evaluated and complications reported. Follow‐up information was evaluated by a telephone questionnaire. Results: All dogs were continent immediately after the procedure. Incontinence recurred 2 months after surgery in 1 dog and was treated by phenylpropanolamine administration. At mean follow‐up time of 11.3 months, 6 of 7 dogs were continent. An iatrogenic urethral tear occurred intraoperatively in 1 dog. No postoperative complications were encountered. The postoperative UPPs showed significantly increased maximal urethral closure pressure and integrated pressure. Postoperative vaginourethrograms were unremarkable. The surgical procedure did not modify the location of the urinary bladder neck in dogs with a “pelvic urinary bladder” preoperatively. Conclusions: TVT‐O was efficient in maintaining short term continence in 6 of 7 dogs affected with USMI.     

Evaluation of the urodynamic and hemodynamic effects of orally administered phenylpropanolamine and ephedrine in female dogs

OBJECTIVE: To compare the urodynamic and hemodynamic effects of different dosages of phenylpropanolamine and ephedrine and determine effective dosages in increasing urethral resistance in female dogs. ANIMALS: 20 sexually intact female Beagles. PROCEDURE: Dogs were allocated into 4 groups and received phenylpropanolamine once, twice, or 3 times daily, or ephedrine twice daily, for 14 days. On days 0, 7, and 14, urethral pressure profiles were performed while dogs were anesthetized with propofol. Variables recorded included maximum urethral pressure, maximum urethral closure pressure, integrated pressure, functional profile length, anatomic profile length, plateau distance, distance before maximum urethral pressure, and maximum meatus pressure. Arterial and central venous pressures were measured before anesthetic induction and 10 and 35 minutes after induction. RESULTS: Administration of phenylpropanolamine once daily or ephedrine twice daily significantly increased maximum urethral pressure and maximum urethral closure pressure. Values for integrated pressure were significantly increased after 14 days of once-daily administration of phenylpropanolamine. Variables did not change significantly from day 7 to day 14. Diastolic and mean arterial blood pressures increased significantly during the treatment periods, and arterial pressure decreased during propofol infusion. CONCLUSIONS AND CLINICAL RELEVANCE: Oral administration of phenylpropanolamine once daily or ephedrine twice daily increased urethral resistance in clinically normal dogs and may be recommended for management of urethral sphincter mechanism incompetence. Treatment efficacy may be assessed after 1 week. Dogs with concurrent cardiovascular disease should be monitored for blood pressure while receiving alpha-adrenergic agents because of the effects on diastolic and mean arterial pressure.     

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.