Transpelvic urethrostomy in a Staffordshire bull terrier: a new technique in the dog

An eight-year-old male Staffordshire bull terrier was presented with a bleeding mass in the urethral mucosa 1.5 cm distal to the ischial arch. After cytological findings suggestive of a squamous cell carcinoma and confirmation of the mass with urethroscopy, total penile amputation followed by transpelvic urethrostomy using an ischial symphyseal ostectomy was performed. The procedure successfully produced a tension-free anastomosis of the urethra to the skin in the scrotal position and no major complications were observed in the postoperative period. Histologically, the lesion was reported as a ruptured vascular structure with thrombosis and repair tissue. Seven months after surgery the dog is free of clinical signs.     

Ischial ostectomy in direct end-to-end anastomosis of the pelvic urethra in male dogs

Ischial ostectomy in conjunction with direct end-to-end anastomosis of the pelvic urethra was performed after prostatectomy in cadavers of 10 male dogs with normal bladder and urethra, and in a mongrel dog with an enlarged prostrate and transection injury of the pelvic urethra. In the cadavers, tension on the suture line was assessed from the intravesical pressure (IVP) and volume of normal saline solution (NSS) instilled into the bladder to cause dehiscence of the anastomosis before and after the ostectomy. The experiment found that the IVP and instilled NSS volume after the ischial ostectomy were significantly (p<0.01) higher than those before the ostectomy, suggesting the ostectomy can reduce tension on the suture line and risk of dehiscence. Clinically, the dog had uneventful recovery with normal urination. Fluoroscopic examination of the caudal abdomen at 3 and 16weeks after surgery revealed urethral continuity without perforation and narrowing of the anastomosis site.     

Vaginourethroplasty as a salvage procedure for management of traumatic urethral rupture in a cat

This report describes a cat that suffered pelvic urethral rupture associated with multiple pelvic fractures. A vaginourethroplasty was performed as a salvage procedure, via intrapelvic anastomosis of the proximal urethra to the caudal vagina, following failure of a primary urethral anastomosis. Urinary diversion was achieved via tube cystostomy and a vagino-urethral catheter was maintained for 3 days postoperatively. Anterograde cystourethrography was performed at 7 days and 14 days postoperatively. Absence of contrast leakage from the vagino-urethral anastomosis was documented at 14 days postoperatively and the tube cystostomy was removed. An Escherichia coli urinary tract infection was treated following removal of the tube cystostomy and subsequent urine culture revealed no evidence of urinary tract infection. The cat retained normal urinary continence and elimination behaviour during the 7-month follow-up period. Vaginourethroplasty could be considered as a salvage option for management of traumatic pelvic urethral rupture in the neutered female cat.     

Colliculus seminalis as a cause of a urethral filling defect in two dogs with Sertoli cell testicular neoplasms

A urethral filling defect in the proximal portion of the pelvic urethra, suggestive of a mass, was detected by positive-contrast retrograde urethrography in 2 dogs with prostatic disease and Sertoli cell neoplasms. Extension of prostatic neoplasia into the urethra or primary urethral neoplasia were considered as explanations for the radiographic finding of an intraluminal filling defect in the pelvic urethra. Masses were visualized and biopsied during prostatic surgery. Masses were nonneoplastic and represented enlargement of the colliculus seminalis.     

Subtotal penile amputation and preputial urethrostomy in a dog

CASE DESCRIPTION: A 6-year-old castrated male Shih Tzu was evaluated because of intermittent bleeding during urination. CLINICAL FINDINGS: Necrosis of the cranial portion of the penile shaft extended distally from the preputial fornix. Penile necrosis secondary to strangulation from paraphimosis was diagnosed. TREATMENT AND OUTCOME: A midline preputiotomy incision was used to expose the penile shaft; amputation was performed caudal to the preputial fornix. The terminal portion of the urethra was anastomosed to the preputial mucosa, which allowed the dog to urinate through the preputial orifice. CLINICAL RELEVANCE: Unlike the more conventional urethrostomy procedures performed in dogs, preputial urethrostomy eliminates the potential for local skin irritation during urination. Preputial urethrostomy is also easier to perform in those dogs in which penile amputation is required adjacent to the preputial fornix. A release incision cranial to the prepuce can be used to facilitate caudal displacement of the preputial mucosa, which facilitates urethral anastomosis to this structure. A midline preputiotomy incision provided excellent exposure of the penile shaft for this surgical procedure.     

Proximal Urethral Reconstruction Using a Distally Based Ventral Bladder Tube Flap An Experimental Study

Reconstruction of the proximal urethra using a distally based tube flap mobilized from the ventral bladder wall was performed on 12 clinically normal dogs after total prostatectomy and resection of 2 cm of membranous urethra. One dog was euthanized at 6 hours and one at 36 hours after surgery because of surgical complications. Five dogs were euthanized at 10 days, two dogs at 6 weeks and three dogs at 12 weeks. Advancement of the tube flap allowed for tension-free anastomosis to the membranous urethra. Vascular integrity was maintained in all flaps. Intermittent to continuous postoperative urinary incontinence occurred in 7 of 10 dogs. The incontinence was transient in all 6 and 12 week dogs except one in which a persistent stress incontinence developed. Mild to severe dysuria was noted in 8 of 10 dogs, but was also transient in all of the 6 and 12 week dogs, with the exception of one dog. Postoperative urethral closure pressure profilometry revealed decreased tone in the membranous urethra in all 6 and 12 week dogs. It was concluded that proximal urethral reconstruction, using a ventral bladder tube flap, is a viable technique that may permit functional urodynamic recovery in dogs with significant proximal urethral loss.     

Experimental Use of Fluoroalkyl Cyanoacrylate in Canine Urethral Anastomosis

The results of a study designed to evaluate a fluoroalkyl cyanoacrylate tissue adhesive as an adjunct to suture anastomosis of the severed canine pelvic urethra are presented. The urethral anastomotic sites were evaluated by contrast radiography, gross pathology, and histopathology. Urethral anastomosis resulted in a clinically functional urethra in all 6 control dogs (suture anastomosis) and 5 of the 6 test dogs (suture anastomosis plus adhesive). A severe stricture at the anastomotic site developed in 1 dog in the test group. Evidence of leakage was detected by contrast radiography in 1 dog of each group. Microscopic evidence of incomplete closure was detected in 4 control dogs and 2 test dogs. An extensive granulomatous inflammatory reaction was associated with use of the adhesive. The lower incidence of microscopic leakage observed in the test dogs was attributed to fibroplasia induced by the cyanoacrylate and not to the adhesive properties of the cyanoacrylate.     

Intrapelvic Urethral Anastomosis A Comparison of Three Techniques

Three intrapelvic urethral anastomosis techniques were performed on 12 mature male dogs to compare the degree of stricture. The intrapelvic urethra was transected 1 cm caudal to the prostate, and anastomosis was performed using either suturing of the urethra over an indwelling catheter, suturing of the urethra without an indwelling catheter, or apposition of the urethra without sutures over an indwelling catheter. Postoperatively, the dogs were evaluated using clinical urination patterns, biochemical tests, radiography, and pathology. Three of four suture-catheter dogs and one of four catheter-only dogs had normal urinary patterns. Stricture (25-84%) with urethral dilation or fistulas tracts was visible on retrograde, positive contrast urethrograms of 3 of 12 intact dogs 20 weeks after surgery, and on all 12 excised lower urinary tracts. Suture-catheter dogs subjectively had the least amount of stricture. All eight dogs (1 suture-catheter dog, 4 suture-only dogs, and 3 catheter-only dogs) with severe stricture (greater than 60% lumen diameter reduction) had histopathologic signs of chronic, inflammatory urinary tract disease, including four with chronic, ascending lymphocytic pyelonephritis. Hydroureter and hydronephrosis developed in two catheter-only dogs. Complete urethral transection resulted in some degree of stricture, regardless of technique used for anastomosis. Urethral anastomosis over an indwelling catheter appeared to result in a lesser degree of stricture and clinical and histopathologic derangement.     

Complications associated with transurethral endoscopic‐assisted electrohydraulic lithotripsy for treatment of a bladder calculus in a gelding

A cystic calculus approximately 6 cm in diameter was diagnosed by ultrasonography and endoscopy in a 12‐year‐old Trakehner gelding with a history of haematuria and dysuria. Transurethral endoscopic lithotripsy with electrohydraulic shock waves was performed as a minimally invasive treatment option. Fragmentation of the calculus was achieved, the fragments of the calculus left in the bladder and excretion assisted by infusion of Ringer's solution. Twenty‐four hours after the third lithotripsy, the horse suffered a recurrence of dysuria and pollakiuria due to partial obstruction of the urethra by the calculus fragments. The treatment was repeated within the urethra until clearance of the fragments was achieved. The sharp fragments had produced a zone of urethral mucosal trauma, approximately 10 cm in length. At the follow‐up visit 4 weeks later, the patient had developed inflammation and swelling of the urethral mucosa, which was successfully treated with a 14 day course of anti‐inflammatory drugs. This resulted in normal urination. At the last follow‐up, the horse had been recurrence‐free for 12 months.     

Neodymium:yttrium-aluminum-garnet laser ablation of a urethral web to relieve urinary outflow obstruction in a horse.

An 8-year-old Hanoverian gelding was examined because of urine dribbling and urethral obstruction. Mild proprioceptive deficits of the left hind limb were evident during neurologic examination. Ultrasonography per rectum revealed dilatation of the pelvic portion of the urethra. Endoscopy of the urethra revealed 2 webs of tissue: 1 was located 10 cm proximal to the external urethral opening; the other was located 65 cm proximal to the external urethral opening and prevented passage of the endoscope into the urinary bladder. The mass was ablated with a neodymium:yttrium-aluminum-garnet laser, using a transendoscopic noncontact technique. On follow-up examination 6 months after laser surgery, an endoscope could easily be passed into the bladder, and no urethral web was seen. The horse was able to void a stream of urine but continued to dribble urine intermittently. The proximal location of the urethral lesion in this horse would have made use of traditional surgical methods problematic, whereas transendoscopic laser photoablation was easy and effective.     

Urethral haemangiosarcoma in a boxer

A seven-year-old, entire female boxer presented with a history of restless behaviour and inappetence. Physical examination revealed that the dog was listless and had a hunched gait. Neurological examination was normal. Abdominal ultrasonography revealed a 4 cm x 4 cm mass in the cranial pelvic canal. Neurological abnormalities were detected three days after presentation, and progressed from proprioceptive deficits to loss of deep pain sensation in the pelvic limbs over a two-day period. The dog was euthanased and postmortem examination revealed that the pelvic mass was a urethral haemangiosarcoma with metastasis to the second lumbar vertebra. This case is unusual as urethral tumours are usually transitional cell carcinomas and frequently present with signs of dysuria.     

Urethral transitional cell carcinoma in a cat

A 15-year-old, male neutered cat was referred for investigation of dysuria. A retrograde urethrography was performed which showed two space-occupying masses within the lumen of the mid-to-proximal urethra. Exploratory coeliotomy revealed two urethral masses. Segmental urethrectomy was performed to resect the mass, and the lower urinary tract was reconstructed by vesico-urethral anastomosis. Histopathology showed the mass to be a transitional cell carcinoma with incomplete surgical margins. Tumour regrowth was suspected when dysuria was found approximately 318 days after surgery. Clinical signs were palliated by radiation using weekly fractions of 6 Gy for three weeks. The cat died of unknown causes 386 days postoperatively.     

Traumatic urethral avulsion at the preputial fornix in a cat

A cat with pelvic fractures from being hit by a car had voided no urine in 13 hours despite iv administration of fluids. Abdominal radiography had revealed the pelvic fractures and apparently intact urinary bladder. Urine did not flow from a urethral catheter, and contrast radiography revealed the catheter to be extra-urethral within the penis. Intravenous pyelography revealed intact ureters and urinary bladder; celiotomy confirmed intact urinary bladder. Cystotomy and normograde urethral catheterization allowed localization of the ruptured urethra within the deep subcutaneous tissues of the caudal portion of the abdomen. After closure of the cystotomy and celiotomy incisions, perineal urethrostomy was performed.     

Omentalization of cystic sublumbar lymph node metastases for long-term palliation of tenesmus and dysuria in a dog with anal sac adenocarcinoma.

A 13-year-old castrated male Bassett Hound was examined because of a 2-week history of severe constipation and tenesmus. Radiography revealed a large cystic mass in the caudal portion of the abdomen that was compressing the urethra and obstructing the pelvic canal. A small perianal mass was also noticed in the region of the left anal sac. Exploratory surgery was performed, but the mass was deemed unresectable. Instead, the mass was incised, drained, and omentalized in an attempt to establish continuous drainage after surgery. Cytologic evaluation of the perianal mass was consistent with a diagnosis of anal sac adenocarcinoma. Histologic evaluation of the abdominal mass revealed it was a lymph node effaced by adenocarcinoma. Despite the poor prognosis for anal sac adenocarcinoma with metastatic spread to the sublumbar lymph nodes, tenesmus and dysuria in this dog remained palliated until the dog's death 18 months after surgery. Omentalization was successful in providing a continuous method of fluid drainage for this cystopapillary abdominal tumor.     

Managing traumatic urethral injuries

Urethral injuries are relatively common in male dogs and cats. Urethral epithelium has impressive regenerative properties, and healing by second intention is effective as long as there is mucosal continuity across the traumatized area. Principles of managing traumatic urethral injuries include an accurate patient assessment, including a determination of the extent of the urethral injury; correction of electrolyte or acid-base disturbances; provision of urinary diversion, particularly with pelvic or perineal urethral defects; drainage of extravasated urine; and selection of a surgical procedure to repair or bypass the injured portion of urethra. Treatment options include temporary urinary diversion through cystostomy or urethral catheterization and second intention healing, permanent bypassing of the traumatized area through urethrostomy proximal to the injury site, and primary repair of transection injuries. The scrotal site is the most frequently used and preferred site for urethrostomy in the male dog to bypass the injured penile urethra. Urethral surgery necessitates care and attentiveness to detail, considering that accurate approximation of urethral mucosa minimizes fibrosis and helps maintain an adequate luminal diameter. Avoidance of stricture and preservation of function are goals of managing traumatic urethral injuries.     

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.     

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.     

Application of preputial tube-flap urethroplasty to establish a neourethra in a male dog with complications after preputial urethrostomy

A 14-year-old male poodle weighing 7.5 kg presented due to complications after preputial urethrostomy for management of preprostatic urethral rupture. Revision surgery was performed with preputial tube-flap urethroplasty via preputiotomy. A longitudinal flap was raised from the prepuce and anastomosed to the end of the previously cut urethra to create a neourethra and reduce tension at the urethrostomy site. Follow-up retrograde positive contrast urethrography performed 10 days and 6 months postoperatively showed no contrast leakage from either the neourethra tube flap or new preputial urethrostomy. A follow-up email questionnaire, based on the American Urological Association Symptom Index, was completed by the owner 6 months after surgery. The dog had excellent symptom scores, and urinated from the prepuce without difficulty in a manner resembling physiological urination.     

IMAGING DIAGNOSIS‐INFILTRATIVE LIPOMA CAUSING SPINAL CORD AND LUMBAR NERVE ROOT COMPRESSION IN A DOG

A 12‐year‐old, male, fox terrier dog presented with an abnormal gait of the left pelvic limb. Computed tomography revealed a large, homogeneous, hypoattenuating, noncontrast enhancing mass within the left epaxial muscles that invaded the L5–6 vertebral canal and caused spinal cord compression. Imaging findings were consistent with an infiltrative lipoma. The mass was removed and a left hemilaminectomy was performed in the affected area. Histopathology confirmed the mass to be an infiltrative lipoma. The dog recovered and regained neurologic function within 2 weeks. Computed tomography assisted preoperative planning by characterizing the shape, size, and location of the mass.     

One stage functional end-to-end stapled intestinal anastomosis and resection performed by nonexpert surgeons for the treatment of small intestinal obstruction in 30 dogs

Objectives: To describe stapled 1‐stage functional end‐to‐end intestinal anastomosis for treatment of small intestinal obstruction in dogs and evaluate outcome when the technique is performed by nonexpert surgeons after limited training in the technique. Study Design: Case series. Animals: Dogs (n=30) with intestinal lesions requiring an enterectomy. Methods: Stapled 1‐stage functional end‐to‐end anastomosis and resection using a GIA‐60 and a TA‐55 stapling devices were performed under supervision of senior residents and faculty surgeons by junior surgeons previously trained in the technique on pigs. Procedure duration and technical problems were recorded. Short‐term results were collected during hospitalization and at suture removal. Long‐term outcome was established by clinical and ultrasonographic examinations at least 2 months after surgery and from written questionnaires, completed by owners. Results: Mean±SD procedure duration was 15±12 minutes. Postoperative recovery was uneventful in 25 dogs. One dog had anastomotic leakage, 1 had a localized abscess at the transverse staple line, and 3 dogs developed an incisional abdominal wall abscess. No long‐term complications occurred (follow‐up, 2–32 months). Conclusion: Stapled 1‐stage functional end‐to‐end anastomosis and resection is a fast and safe procedure in the hand of nonexpert but trained surgeons.