Treatment of fibrosarcoma in a maned wolf (Chrysocyon brachyurus) by rostral maxillectomy.

A 12-yr-old captive intact male maned wolf (Chrysocyon brachyurus) was diagnosed with a fibrosarcoma of the incisive bones. The mass was excised by rostral maxillectomy, and the wolf remained normal and on display with good function and cosmetics for 7 mo. Subsequently, it became weak, ataxic, and dyspneic and was euthanatized. At necropsy, there was a small regrowth of the maxillary tumor, a metastatic mediastinal mass, and multiple metastatic lung masses, suggesting that oral fibrosarcoma in maned wolves behaves similarly to oral fibrosarcoma in domestic canines. Aggressive surgical treatment of oral fibrosarcoma in this species can achieve good functional and cosmetic results.

Tracheal rupture in cats: 16 cases (1983-1998).

OBJECTIVE: To determine causes of tracheal rupture in cats and the mechanism of injury. DESIGN: A retrospective study was conducted to identify cats with tracheal rupture. A second study was conducted to establish mechanism of injury, and a third study was conducted to determine volume of air needed to obtain an airtight seal when inflating the cuff of an endotracheal tube in a cat. ANIMALS: 16 cats with clinical signs of tracheal rupture, 10 cat cadavers, and 20 clinically normal cats that were undergoing anesthesia. PROCEDURES: Details were extracted from medical records of 16 cats with tracheal rupture (9 treated surgically and 7 treated conservatively). For the cadaver study, the trachea of each cat cadaver was intubated and observed during overinflation of the endotracheal tube cuff. For clinically normal cats, volume of air needed to obtain an airtight seal for the endotracheal tube was recorded. RESULTS: Most ruptures were associated with cats anesthetized for dental procedures. Clinical signs associated with tracheal rupture included subcutaneous emphysema, coughing, gagging, dyspnea, anorexia, and fever. Tracheoscopy was the method of choice for documenting tracheal rupture. Surgical and conservative management were successfully used, unless the injury extended to the carina. In the cadaver study, overinflation of the endotracheal tube cuff with > 6 ml of air resulted in tracheal rupture in 7 of 10 cadavers. For clinically normal cats, the volume of air (mean +/- SD) needed to obtain an airtight seal was 1.6 +/- 0.7 ml. CLINICAL IMPLICATIONS: Overinflation of an endotracheal tube cuff may result in tracheal rupture in cats.

Surgical management of bifid sternum in two African grey parrots.

Transposition of the pectoral muscles for treatment of caudal bifid (cleft) sternum in 2 unrelated African Grey Parrots is described. The birds did not have clinical signs of ventilatory compromise prior to surgery; however, both had cutaneous ulcers over the defects. The pectoral muscles provided a thick pad over the heart, minimizing the risk of trauma to the heart.

Principles of surgery for cancer palliation and treatment of metastases.

Surgery in animals for palliation of clinical signs and treatment of cancer metastases is becoming more popular. Patients must be selected carefully and clear treatment goals established to maximize efficacy and minimize treatment-related morbidity and mortality. Palliative treatment is rendered primarily to control clinical signs and secondarily to prolong life. Ironically, metastasectomy is often performed with the intent to cure. For both considerations, the clinician must be knowledgeable of the natural history of the affecting neoplasia (i.e., how will the patient fare without treatment) and the success rates and expected complications of the surgical procedures being considered. Clinical guidelines for patient selection are presented and discussed for palliative treatment and metastasectomy. Although data are available in the human and veterinary medical literature to aid decision making, sound clinical judgment remains most important for proper patient selection and care.

Use of colostomy to manage rectal disease in dogs.

OBJECTIVE: The purpose of this study was to develop a diverting colostomy technique for use in dogs. STUDY DESIGN: Clinical case series. ANIMALS: Five client-owned dogs presented for diseases requiring diverting colostomy during treatment. METHODS: Diverting colostomy was performed in five dogs. A ventral approach was used in the first dog and the colon was exteriorized adjacent to the linea alba. The technique used in the next four dogs involved creation of a left flank rod-supported loop colostomy in which the colon was exteriorized through a muscle-separating flank approach to the abdomen. RESULTS: Peritoneal leakage of fecal material resulted in the perioperative death of the first dog. The flank colostomies were maintained for times ranging form 3.5 weeks to 7 months. No major complications were observed, but skin excoriation occurred occasionally around the stoma sites in all dogs. CONCLUSION: Diverting colostomy is a technique that is suitable for use in treatment of dogs with obstruction or leakage involving the distal colon or rectum.

Partial cystectomy for urinary bladder neoplasia: surgical technique and outcome in 11 dogs.

Partial cystectomy was performed in 11 dogs with bladder neoplasia (10 with transitional cell carcinoma and one with rhabdomyosarcoma). Between 40 and 70 per cent of the bladder was excised during the partial cystectomies. In eight dogs, all the grossly visible tumour was excised but on histopathological examination of the excised tissue, neoplastic tissue was found to extend to the surgical margins in four of these dogs. A ureteral stoma was excised with the tumour in four dogs necessitating ureteral reimplantation; one dog had both ureteral stomas excised and bilateral ureteral reimplantation. The bladder incision dehisced in two dogs, necessitating a second surgery. Six dogs were pollakiuric after surgery. Pollakiuria resolved within two months in four dogs and persisted in two dogs. None was incontinent. Local tumour recurrence was suspected in nine dogs based on imaging studies and confirmed in five dogs during post mortem examination. Five dogs were euthanased two to seven months after surgery. Six dogs survived at least one year, two of these dogs remain alive at 17 and 27 months after surgery. It is concluded that partial cystectomy may provide local control of bladder neoplasia.

Fatal reexpansion pulmonary edema in a kitten following surgical correction of pectus excavatum.

Fulminant, fatal pulmonary edema developed in an eight-week-old kitten following external splint correction of severe pectus excavatum. History, signalment, onset of clinical signs, and gross pathological findings were most compatible with a diagnosis of reexpansion pulmonary edema (RPE). This report presents case findings and a literature review of RPE.

Placement of a permanent cystostomy catheter to relieve urine outflow obstruction in dogs with transitional cell carcinoma.

Permanent cystostomy catheters were placed in 7 dogs to relieve urine outflow obstruction from presumed transitional cell carcinoma of the bladder trigone and urethra. The catheters were easily managed at home by the owners. Complications were minimal. The most frequent complication was urinary tract infection. Two owners complained of difficulty in draining the bladder 1 week before euthanasia of their dogs. The primary reason for euthanasia of all dogs was progression of the tumor. Survival times of these dogs were similar to those previously reported for dogs with transitional cell carcinoma involving the bladder and urethra, irrespective of treatment. Placement of a permanent cystostomy catheter should be considered in dogs with transitional cell carcinoma associated with urine outflow obstruction when, owing to the dog's condition or the owner's preference, radical surgery or other treatment is not an option.

Clinical management of the regional lymph node.

Appropriate clinical management of the regional lymph node remains controversial. This article briefly reviews the anatomy and physiology of the lymphatic system, pathophysiology of lymphatic metastases, and some guidelines and rationale for clinical management.

Principles of surgical oncology.

Surgical treatment of cancer has many advantages over other treatment modalities. The principles of defining the goal of surgery, surgical planning, surgical technique, surgical margins, and patient aftercare are reviewed. Special attention is devoted to tumor seeding and obtaining adequate margins. Incorporation of biologic behavior and stage of disease into the surgical plan are paramount to the successful implementation of surgery in cancer treatment.

Surgical treatment of pheochromocytoma: technique, complications, and results in six dogs.

Six dogs were diagnosed with pheochromocytoma and staged according to the World Health Organization's system for tumor classification. Two dogs had benign tumors (T1, N0, M0) and four dogs had malignant tumors (T2, N0, M1 or T3, N0, M0). All dogs had adrenalectomy, two dogs had concurrent nephrectomy, and three dogs had concurrent resection of a tumor thrombus from the vena cava. Anesthetic complications occurred in five dogs, including wide variations in heart rate (four dogs), blood pressure (five dogs), and cardiac arrhythmias (one dog). One dog died 12 hours after surgery from partial dehiscence of the suture line and hemorrhage from the vena cava, and one dog died 6 days after surgery during general anesthesia for treatment of laryngeal paralysis. Four dogs survived from 3 to 23 months (median, 15 months). One dog remained hypertensive after surgery. Benign and malignant pheochromocytomas seem to be amenable to surgical resection.

Pheochromocytoma in 50 dogs.

Fifty dogs with pheochromocytoma were identified in a retrospective study of a 9-year period. For 24 of 50 dogs (48%), the tumor was an incidental finding during necropsy or surgery. Presenting signs were referrable to the nervous system in 7 of the 26 symptomatic dogs (27%); were referrable to the cardiopulmonary system in 7 of 26 dogs (27%); or were nonspecific, reflecting general systemic disease, in 17 of 26 dogs (65%). Abnormal clinical findings were highly varied but were also generally referrable to the cardiopulmonary and nervous systems. Six of 7 dogs (86%) evaluated were hypertensive (systolic range, 164 to 325 mm Hg; diastolic range, 110 to 198 mm Hg). Serum biochemical findings were nonspecific, although 11 of 39 dogs (28%) were hypercholesterolemic. Abdominal fluid samples were analyzed in 6 dogs; 3 were nondiagnostic, and 3 were interpreted as lymphosarcoma. The imaging studies that were of most value included abdominal radiographs (mass identified in 9 of 16 dogs [56%]), caudal vena caval angiography (tumor thrombus correctly diagnosed in 4 of 7 dogs [57%]), and abdominal ultrasonography (mass seen in 5 of 6 dogs [83%] and tumor thrombus seen in 3 of 5 dogs [60%]). Local tumor invasion was present in 26 of 50 dogs (52%), regional lymph node metastases in 6 of 50 dogs (12%), and distant metastases in 12 of 50 dogs (24%). Cause of death was tumor-related in 19 of 50 dogs (38%) and non-tumor related in 28 of 50 dogs (54%).

Effect of diet on results obtained by use of two commercial test kits for detection of occult blood in feces of dogs.

To evaluate the effect of diet on results obtained by use of 2 commercial test kits for detection of occult blood in feces, 5 dogs were fed 7 diets in randomized sequence. Dry and canned diets with various principal ingredients were evaluated. Each diet was offered twice over a 24-hour period, followed by a 36-hour nonfeeding period. Fecal specimens were collected twice daily, and tests for occult blood were performed within 12 hours. The dietary origin of fecal specimens was confirmed by use of colored markers fed with each diet, and was correlated with estimates of gastrointestinal tract transit time. A modified guaiac paper test and an o-tolidine tablet test were performed on each specimen. Of 59 specimens, 4 were positive for occult blood, using the o-tolidine tablet test. Three positive results were associated with a mutton-based canned diet, and 1 positive result was associated with a canned beef-based diet. Of 59 specimens, 11 were positive for occult blood, using the modified guaiac paper test. Four positive results were associated with the mutton diet, and 3 positive results were associated with the beef diet. Of the remaining 5 diets, 4 caused 1 positive reaction. Results were inconsistent with the null hypothesis that the distribution of positive occult blood test results is not affected by diet (P < 0.025), and indicate that diet can affect the specificity of peroxidase-based tests for detection of occult blood in canine feces. Diet modification prior to testing is recommended.

Unusual prostatic mass in a dog.

Marginal surgical resection and castration were successfully used to treat a dog with a large benign mass involving only the left lobe of the prostate. Pathologic findings were compatible with unusual nodular hyperplasia or adenoma, with smooth muscle proliferation. Although the definitive diagnosis remains controversial, the mass was termed nodular hyperplasia because of histologic and clinical similarities to the disease in human beings.

Sinus mucocele secondary to craniofacial trauma in a dog.

A sinsus mucocele formed in the frontal sinus of a dog secondary to obstruction of the nasofrontal opening. The dog was successfully treated by surgical enlargement of the nasofrontal opening, curettage of the sinus epithelium, and placement of a fat graft and drain in the sinus. Although mucocele formation is uncommon in animals, it should be considered as a differential diagnosis for masses of the sinonasal area. Characteristic radiographic and cytologic findings should alert the clinician to this diagnosis, and along with aggressive treatment, should shorten the diagnostic and treatment delay experienced by the dog in this report.

Evaluation of two commercial test kits for detection of occult blood in feces of dogs.

To evaluate the sensitivity and specificity of 2 commercial test kits for detection of occult blood in canine feces, various volumes of blood were administered to 6 dogs via orogastric tube. Blood volumes tested were chosen on the basis of hemoglobin quantities of 5, 10, 20, 200, 350, and 500 mg of hemoglobin/kg of body weight. Fecal specimens were collected twice daily and analyzed separately by 2 observers for the presence of occult blood by use of modified guaiac and orthotolodine tablet tests, and for melena by visual inspection. Five dogs given blood at the rate of 500 mg of hemoglobin/kg and 1 dog given blood at the rate of 350 mg of hemoglobin/kg developed melena. Results of both occult blood tests were positive in 2 of 6 dogs given blood at the rate of 5 mg of hemoglobin/kg. Five of 6, and 4 of 6 dogs given blood at the rate of 10 mg hemoglobin/kg had positive test results by modified guaiac and orthotolodine methods, respectively. Results of both methods were positive in all dogs given blood at the rate of 20 mg of hemoglobin/kg. There was 86% agreement between the 2 observers' results for the modified guaiac method, and 78% agreement for the orthotolodine method. There was 77% agreement of results between the 2 test methods. Gastrointestinal transit time decreased with increasing volumes of blood. Occult blood testing was found to be useful for detection of blood in feces at volumes 20 to 50 times less than that required to cause melena.

Surgically induced tumor seeding in eight dogs and two cats.

Surgically induced tumor seeding was diagnosed in 8 dogs and 2 cats. All animals had histologic confirmation of neoplasia in an unusual location or pattern, and a history of surgical manipulation of a similar histologic-type tumor at the site of seeding. Highly malignant carcinomas (8/10 animals) were the most common tumor type. Seeding occurred secondary to a variety of surgical procedures and in the face of various adjuvant therapies. Seeded tumors were recognized from 2 to 30 weeks after the causal procedure (median, 6 weeks). Survival times after the causal procedure ranged from 15 to 131 weeks (median, 45 weeks) and 8 of 10 animals died or were euthanatized because of seeded tumors.

Treatment of humeroulnar subluxation with a dynamic proximal ulnar osteotomy. A review of 13 cases.

Humeroulnar subluxation was treated surgically in 13 dogs with 18 affected elbows using a proximal osteotomy of the ulna that allowed the ulna to elongate dynamically. Distal humeroulnar subluxation was secondary to premature closure of the distal ulnar physis in 16 elbows. One distal subluxation was secondary to a radioulnar synostosis, and one proximal subluxation developed after premature closure of the distal radial physis. The mean follow-up time was 22 months. Twenty-eight percent of the elbows were judged to have excellent results, 22% good results, 50% fair results, and none was judged to have a poor outcome. The presenting lameness grade and the severity of preoperative and postoperative humeroulnar subluxation had significant correlations with the prognosis. Associated orthopedic abnormalities and complications of concurrent surgical procedures affected the outcome in several dogs. Overall, the dynamic proximal ulnar osteotomy was a simple and effective technique for the treatment of uncomplicated humeroulnar subluxation.