Concurrent pituitary and adrenal tumors in dogs with hyperadrenocorticism: 17 cases (1978-1995).

OBJECTIVE: To describe the clinicopathologic characteristics of dogs with hyperadrenocorticism and concurrent pituitary and adrenal tumors. DESIGN: Retrospective study. ANIMALS: 17 client-owned dogs. PROCEDURE: Signalment, response to treatment, and results of CBC, serum biochemical analysis, urinalysis, endocrine testing, and histologic examinations were obtained from medical records of dogs with hyperadrenocorticism and concurrent adrenal and chromophobe pituitary tumors. RESULTS: On the basis of results of adrenal function tests and histologic examination of tissue specimens collected during surgery and necropsy, concurrent pituitary and adrenal tumors were identified in 17 of approximately 1,500 dogs with hyperadrenocorticism. Twelve were neutered females, 5 were males (3 sexually intact, 2 neutered); and median age was 12 years (range, 7 to 16 years). Hyperadrenocorticism had been diagnosed by use of low-dose dexamethasone suppression tests and ACTH stimulation tests. During high-dose dexamethasone suppression testing of 16 dogs, serum cortisol concentrations remained high in 11 dogs but decreased in 5 dogs. Plasma concentrations of endogenous ACTH were either high or within the higher limits of the reference range (12/16 dogs), within the lower limits of the reference range (2/16), or low (2/16). Adrenal lesions identified by histologic examination included unilateral cortical adenoma with contralateral hyperplasia (10/17), bilateral cortical adenomas (4/17), and unilateral carcinoma with contralateral hyperplasia (3/17). Pituitary lesions included a chromophobe microadenoma (12/17), macroadenoma (4/17), and carcinoma (1/17). CLINICAL IMPLICATIONS: Pituitary and adrenal tumors can coexist in dogs with hyperadrenocorticism, resulting in a confusing mixture of test results that may complicate diagnosis and treatment of hyperadrenocorticism.     

Eclampsia in dogs: 31 cases (1995-1998)

OBJECTIVE: To compare clinical characteristics and laboratory findings of dogs with eclampsia with those of dogs without eclampsia. DESIGN: Retrospective study. ANIMALS: 31 dogs with eclampsia (affected) and 31 with dystocia (controls). PROCEDURE: Information on signalment, type of diet, reproductive history, litter size, time from whelping to eclampsia, body weight, clinical signs, results of physical examination and hematologic and biochemical analyses, response to calcium supplementation, and recurrence was obtained from the medical records of all dogs with eclampsia evaluated between 1995 and 1998 and compared with information from medical records of 31 of 102 dogs with dystocia evaluated during the same period. RESULTS: Dogs with eclampsia weighed less, had a smaller body weight-to-litter size ratio, higher rectal temperature and heart and respiratory rates, and lower plasma total solids concentration than control dogs. Ionized calcium concentration was < or = 0.8 mmol/L for all but 1 of the affected dogs; median concentration for the affected dogs was significantly less than that for control dogs. Six (19%) dogs did not manifest typical clinical signs associated with eclampsia. Twelve (39%) dogs with eclampsia had previous litters; none had a history of eclampsia. Affected dogs were discharged from the hospital within hours after admission, but 3 dogs returned 1 to 3 weeks later because of recurrence of eclampsia. CONCLUSIONS AND CLINICAL RELEVANCE: Eclampsia develops primarily in small-breed dogs with large litters. Plasma ionized calcium concentrations > 0.8 mmol/L in dogs with clinical signs typical of hypocalcemia may indicate that other causes of clinical signs should be considered. In addition, some dogs with eclampsia may have low ionized calcium concentrations and not manifest typical clinical signs.     

Treatment of chronic pleural effusion with pleuroperitoneal shunts in dogs: 14 cases (1985-1999).

OBJECTIVE: To describe complications and outcome associated with chronic nonseptic pleural effusion treated with pleuroperitoneal shunts in dogs. DESIGN: Retrospective study. ANIMALS: 14 dogs. PROCEDURE: Medical records at 4 veterinary schools were examined to identify dogs with chronic nonseptic pleural effusion that were treated by use of a pleuroperitoneal shunt between 1985 and 1999. Signalment, history, physical examination and laboratory findings, cause and type of pleural effusion, medical and surgical treatments, complications, and outcome were reviewed. RESULTS: 10 of 14 dogs had idiopathic chylothorax, and 4 had an identified disease. All but 1 dog with idiopathic chylothorax and 1 dog with chylothorax from a heart base tumor had unsuccessful thoracic duct ligation prior to pump placement. No intraoperative complications developed during shunt placement. Short-term complications developed in 7 of 13 dogs, necessitating shunt removal in 2 dogs and euthanasia in 1. Eight of 11 dogs with long-term follow-up developed complications; the overall mean survival time and the interval in which dogs remained free of clinical signs of pleural effusion were 27 months (range, 1 to 108 months) and 20 months (range, 0.5 to 108 months), respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Pleuroperitoneal shunts can effectively palliate clinical signs associated with intractable pleural effusion in dogs. Numerous short- and long-term complications related to the shunt should be expected. Most complications can be successfully managed, but even when shunts are functional some treatments fail because of severe abdominal distension or massive pleural fluid production that overwhelms the functional capacity of the shunt.     

Clinical and microbiologic findings in dogs with bronchoscopically diagnosed tracheal collapse: 37 cases (1990-1995).

OBJECTIVE: To investigate the role of bacteria in bronchoscopically diagnosed tracheal collapse in dogs by evaluating qualitative results of bacteriologic cultures. DESIGN: Retrospective study. ANIMALS: 37 dogs with tracheal collapse. PROCEDURE: Clinical records for dogs with tracheal collapse confirmed with bronchoscopy were reviewed. A protected catheter brush was used to obtain samples for bacteriologic culture from the large airways. RESULTS: Results of bacterial culture were negative for 5 of 29 dogs. For 24 dogs, 1 (n = 10), 2 (6), or > or = 3 (8) species of bacteria were isolated. Pseudomonas spp were isolated most frequently (17/29), and a single Pseudomonas sp grew in 7 samples. Other bacteria included Enterobacter spp (4/29), Citrobacter spp (3/29), and Moraxella spp, Klebsiella spp, Bordetella spp, or Acinetobacter spp (2/29 dogs each). Anaerobic and aerobic cultures yielded positive results in samples from 2 dogs. Cytologic results were available for 13 dogs with positive results of bacteriologic culture; epithelial cells were reported most commonly. Five samples had a small number of neutrophils; bacteria were identified cytologically in 2 of 5 samples that contained neutrophils. Bacteria were also seen in 2 samples that lacked inflammatory cells. CONCLUSIONS AND CLINICAL RELEVANCE: Bacteria are commonly isolated from samples obtained via airway brushing in dogs with tracheal collapse; however, in the absence of cytologic confirmation of inflammation or infection, an association between bacteria and clinical signs of tracheal collapse cannot be established.     

Leiomyosarcoma in dogs: 44 cases (1983-1988).

During a 5-year period, leiomyosarcoma was diagnosed in 57 dogs. Forty-four dogs were included in the study on the basis of completeness of medical records. All dogs underwent exploratory laparotomy, and dogs were allotted to 4 groups according to primary site of tumor: spleen (16 dogs, median age 10.3 years), stomach/small intestine (13 dogs, median age 10.3 years), cecum (10 dogs, median age 11.8 years), and liver (5 dogs, median age 9 years). All dogs with leiomyosarcoma of the liver had visible metastasis and were euthanatized at surgery. In the other 3 groups, 79% of the dogs had no gross evidence of metastasis at surgery, and 64% survived greater than 2 weeks. Median survival in these 3 groups was 10 months (range, 1 month to 7 years); 48% died of metastasis, 32% died of unrelated causes, and 16% died of unknown causes. The prognosis in dogs with leiomyosarcoma of the spleen, stomach, small intestine, and especially the cecum is good to excellent if surgery is performed. In dogs with leiomyosarcoma of the liver, the prognosis is poor.     

Complications of enteroplication for the prevention of intussusception recurrence in dogs: 35 cases (1989-1999).

OBJECTIVE: To compare complication and recurrence rates in dogs treated for intussusception that underwent enteroplication to rates in dogs treated for intussusception that did not undergo enteroplication. DESIGN: Retrospective study. ANIMALS: 35 dogs with intestinal intussusception. PROCEDURE: Information on signalment, clinical signs, potential predisposing causes, surgical technique, opioid administration, use of enteroplication, postoperative complications, and whether the intussusception recurred was obtained from the medical records. RESULTS: Dogs ranged from 8 weeks to 10 years old. Opioids were administered in the perioperative period in 34 dogs. Enteroplication was performed in 16 dogs. Complications of enteroplication that required a second surgery were identified in 3 dogs. None of the 16 dogs that underwent enteroplication had a recurrence of intussusception, whereas 1 of the 19 dogs that did not undergo enteroplication had a recurrence. Rate of intussusception recurrence and likelihood that a second surgical procedure would be required were not significantly different between dogs that underwent enteroplication and dogs that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that enteroplication may be associated with life-threatening complications in dogs, but the likelihood of a dog requiring a second surgical procedure following surgical correction of intussusception was not different between dogs that underwent enteroplication at the time of the initial surgery and dogs that did not.     

Liver lobe torsion in dogs: 13 cases (1995-2004)

OBJECTIVE: To determine history, results of diagnostic testing, surgical findings, complications, and outcome for dogs with liver lobe torsion (LLT). DESIGN: Retrospective case series. ANIMALS: 12 dogs (1 with 2 episodes). PROCEDURE: Signalment, clinical signs, clinicopathologic findings, radiographic and ultrasonographic findings, surgical and histologic findings, complications, and hospitalization time were evaluated. RESULTS: The most common clinical signs were nonspecific abnormalities (eg, vomiting, lethargy, and anorexia) of acute or chronic duration. All dogs were large-breed dogs (median body weight, 37.2 kg [82 lb]). Biochemical abnormalities included high alanine amino-transferase (n = 12) and aspartate aminotransferase (11) activities. Results of abdominal ultrasonography were supportive of the diagnosis in 5 of 8 cases. Affected lobes included the left medial lobe (n = 4), left lateral lobe (3), papillary process of the caudate lobe (2), caudate lobe (1), and right lateral lobe (1). Exploratory celiotomy and liver lobectomy were performed in 12 of 13 cases, and in 11 of those 12 cases, the dog survived. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that development of nonspecific clinical signs of vomiting, lethargy, and anorexia in conjunction with high serum hepatic enzyme activities and mature neutrophilia in a medium-sized or large-breed dog should increase the index of suspicion for LLT. Abdominal ultrasonography with Doppler assessment may be useful in establishing the diagnosis. The long-term outcome for dogs that survive the hospitalization period is excellent.     

Mammary duct ectasia in dogs: 51 cases (1992-1999)

OBJECTIVE: To evaluate the clinical and pathologic characteristics of mammary duct ectasia in dogs. DESIGN: Retrospective study. ANIMALS: 51 dogs with mammary duct ectasia. PROCEDURE: Information regarding body condition, history, number and location of affected mammary glands, appearance of lesions, surgical treatment, nonsurgical treatment, and evidence of recurrence or development of mammary neoplasia was obtained from surveys sent to referring veterinarians. Results of information from examination of histologic sections and referring veterinarians were evaluated for all mammary duct ectasia biopsies performed between 1992 and 1999. RESULTS: Duct ectasia was the primary diagnosis in 51 of 1,825 (2.8%) mammary biopsy specimens and comprised 48% of nonneoplastic mammary diseases. Affected dogs were evenly distributed over a range of 1 to 13 years of age, with a mean age at the time of diagnosis of 6.1 +/- 3.1 years. All dogs were female (31 sexually intact, 20 spayed); 10 of 26 had whelped. Duct ectasia was described as nodular (26 dogs), cystic (13), and multiglandular (11) and located in caudal (31) more often than cranial (14) or middle glands (10). Ectasia recurred in 3 dogs. One dog had a history of previously excised mammary adenocarcinoma; another subsequently developed mammary carcinoma. CONCLUSIONS AND CLINICAL RELEVANCE: Duct ectasia affected mature, sexually intact and spayed female dogs over a wide age range. Certain breeds were affected more commonly than expected. Increased risk for mammary neoplasia was not evident. Duct ectasia should be considered as a cause for mammary enlargement, especially in young dogs or when its cystic nature is evident. Mastectomy is usually curative, and neoplasia should be ruled out in dogs with ectasia.     

5-Hydroxytryptophan toxicosis in dogs: 21 cases (1989-1999)

OBJECTIVE: To determine epidemiologic characteristics, clinical findings, and treatment outcome of 5-hydroxytryptophan (5-HTP) toxicosis in dogs. DESIGN: Retrospective study. ANIMALS: 21 dogs with evidence of accidental 5-HTP ingestion. PROCEDURE: Information was retrieved from the National Animal Poison Control Center database. Records of dogs ingesting 5-HTP between January 1989 and February 1999 were reviewed for information on signalment, dose ingested, clinical signs (onset, severity, duration), treatments administered, and outcome. RESULTS: Clinical signs of toxicosis developed in 19 of 21 (90%) dogs. Neurologic signs included seizures (9 dogs), depression (6), tremors (5), hyperesthesia (5), and ataxia (4). Gastrointestinal tract signs included vomiting or diarrhea (12 dogs), signs of abdominal pain (3), and hypersalivation (2). Other clinical signs were hyperthermia (7 dogs) and transient blindness (3). Three dogs died. No important clinical laboratory or necropsy findings were reported. The doses of 5-HTP ingested ranged from 2.5 to 573 mg/kg (1.1 to 260 mg/lb) of body weight; the minimum toxic dose reported in our study was 23.6 mg/kg (10.7 mg/lb), and the minimum lethal dose was 128 mg/kg (58.1 mg/lb). Onset of signs ranged from 10 minutes to 4 hours after ingestion, and signs lasted up to 36 hours. Of 17 dogs with clinical signs of toxicosis that received treatment, 16 recovered; treatment consisted of decontamination, seizure control, thermoregulation, fluid therapy, and supportive care. CONCLUSIONS AND CLINICAL RELEVANCE: Ingestion of 5-HTP in dogs can result in a potentially life-threatening syndrome resembling serotonin syndrome in humans, which requires prompt and aggressive care.     

Lung lobe torsion in dogs: 22 cases (1981-1999)

OBJECTIVE: To identify breed disposition, postoperative complications, and outcome in dogs with lung lobe torsion. DESIGN: Retrospective study. ANIMALS: 22 client-owned dogs. PROCEDURE: Information on signalment; history; clinical findings; results of clinicopathologic testing, diagnostic imaging, and pleural fluid analysis; surgical treatment; intra- and postoperative complications; histologic findings; and outcome were obtained from medical records. RESULTS: All 22 dogs had pleural effusion; dyspnea was the most common reason for examination. Fifteen dogs were large deep-chested breeds; 5 were toy breeds. Afghan Hounds were overrepresented, compared with the hospital population. One dog was euthanatized without treatment; the remaining dogs underwent exploratory thoracotomy and lung lobectomy. Eleven dogs recovered from surgery without complications, but 3 of these later died of thoracic disease. Four dogs survived to discharge but had clinically important complications within 2 months, including chylothorax, mediastinal mesothelioma, gastric dilatation, and a second lung lobe torsion. Six dogs died or were euthanatized within 2 weeks after surgery because of acute respiratory distress syndrome, pneumonia, septic shock, pneumothorax, or chylothorax. Chylothorax was diagnosed in 8 of the 22 dogs, including 4 Afghan Hounds. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that lung lobe torsion is rare in dogs and develops most frequently in large deep-chested dogs, particularly Afghan Hounds. Other predisposing causes were not identified, but an association with chylothorax was evident, especially in Afghan Hounds. Prognosis for dogs with lung lobe torsion was fair to guarded.     

Inflammatory bowel disease in horses: 11 cases (1988-1998).

OBJECTIVE: To determine clinical and surgical abnormalities in, and long-term outcome of, horses that undergo surgery because of colic secondary to inflammatory bowel disease (IBD). DESIGN: Retrospective study. ANIMALS: 11 horses. PROCEDURE: Medical records of horses that had undergone abdominal surgery and in which IBD had been diagnosed on the basis of histologic examination of intestinal biopsy specimens were reviewed. RESULTS: 5 horses were examined because of acute colic and 6 were examined because of chronic colic. At surgery, all 11 horses had edematous or hemorrhagic bowel segments suggestive of IBD. In addition, 6 horses had circumferential mural bands (CMB) causing constriction of the small (4 horses) or large (2) intestine. Intestinal resections were performed in 7 horses. All 11 horses survived surgery and were discharged from the hospital; 10 horses were still alive at the time of follow-up (1.5 to 7 years after surgery). CLINICAL IMPLICATIONS: Results suggest that IBD is an uncommon cause of colic in horses. Surgical resection of segments of intestine with constrictive CMB may relieve clinical signs of colic. Horses with IBD that had surgery had a good prognosis for long-term survival.     

Lens-induced uveitis in dogs: 151 cases (1985-1990).

During a 5-year period, phacolytic uveitis was diagnosed in 202 eyes of 151 dogs admitted to the veterinary teaching hospital. The diagnosis of phacolytic uveitis was based on the finding of a cataractous lens and anterior uveitis, unassociated with other identifiable causes of uveal inflammation. The most commonly affected breeds were the Toy and Miniature Poodle (35%) and the American Cocker Spaniel (19%). The mean age was 7.0 years for all breeds, 5.1 years for the Cocker Spaniel, and 9.0 years for the Poodle breeds. Evidence of cataract resorption was visible in 72% of the eyes. Fifty-one dogs were affected bilaterally and 100 dogs unilaterally. The mean interval between recognition of the cataract and the onset of lens-induced uveitis (LIU) was 17 months; mean times of 25 and 11 months were seen in the Poodle breeds and American Cocker Spaniel, respectively. The mean age of dogs requiring greater than 1 revisit before the inflammation had subsided was 5.5 years. Complications, referable to the uveitis, were seen in 14% of eyes, the most important of which were glaucoma (16 eyes) and phthisis bulbi (9 eyes). Lens extraction surgery was done on 50 LIU-affected eyes, and on 35 normal eyes in LIU-affected animals. The 2- and 6-month success rates for LIU-affected eyes were 78 and 39%, respectively, and for normal eyes in LIU-affected animals were 85 and 71%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Smoke exposure in dogs: 27 cases (1988-1997).

OBJECTIVE: To evaluate clinical findings, prognostic variables, and clinical course of dogs exposed to smoke. DESIGN: Retrospective study. ANIMALS: 27 dogs exposed to smoke in residential fires. PROCEDURE: Medical records were reviewed for 1988-1997. Time of year, signalment, interval from fire to arrival at veterinary hospital, duration of smoke exposure, clinical signs at the fire scene, physical examination findings, changes in respiratory tract signs, radiographic findings, hematologic and arterial blood gas analyses, initial treatment, clinical course, and outcome were recorded. RESULTS: 27 dogs (16 uncomplicated and 11 complicated cases) were identified. In the complicated group, 4 dogs died, 4 were euthanatized, and 3 had a complicated clinical course. Stupor or coma (8 of 17 dogs), coughing or gagging (6), and respiratory difficulty (6) were commonly observed at the fire scene. Substantial improvement was evident within 5 to 30 minutes after dogs were given supplemental oxygen at the fire scene. More severely affected dogs had a higher median PCV (58%) than less severely affected dogs (50%). Most common thoracic radiographic findings were an alveolar (10 dogs) or an interstitial (3) pattern. CONCLUSIONS AND CLINICAL RELEVANCE: Dogs exposed to smoke can develop respiratory or neurologic complications. Monitoring progression of respiratory problems on the day after the fire may provide clinicians with clues about the severity of each dog's condition.     

Frequency and severity of mastocytemia in dogs with and without mast cell tumors: 120 cases (1995-1997).

OBJECTIVE: To elucidate frequency of detection on blood smears and severity on quantitative buffy coat evaluation of mastocytemia between dogs without mast cell tumors (MCT) and dogs that had MCT, and to expand the list of diseases associated with mastocytemia in dogs without MCT. DESIGN: Retrospective study. ANIMALS: 94 dogs without MCT and 26 dogs with MCT. PROCEDURE: Medical records of all dogs with mast cells detected on blood or buffy coat smears during a 2-year period were reviewed. Dogs with mastocytemia were grouped by disease into dogs with MCT and dogs without MCT. Twenty-five of the dogs without MCT that had mast cells detected on blood smears also had evaluations of buffy coat smears. Quantitative buffy coat results of the 25 dogs without MCT were compared with those of the 26 dogs with MCT. RESULTS: 95.5% of blood smears with mast cells detected during CBC determination were from dogs without MCT. For these dogs, diagnoses included inflammatory disease (28.2%), regenerative anemia (27%), neoplasia other than MCT (25.9%), and trauma (11.8%). Dogs with MCT had a mean of 71.4 mast cells/buffy coat smear, whereas dogs without MCT had a mean of 276.2 mast cells/buffy coat smear. The 2 highest counts of mast cells/buffy coat smear were for dogs without MCT. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of results of quantitative buffy coat evaluations, severity of mastocytemia in dogs without MCT often exceeds that detected during tumor staging in dogs with MCT. Random detection of mast cells in blood smears during CBC determination in dogs is usually not secondary to MCT.     

Outcome of limb amputations in wapiti: 13 cases (1995-2001).

The object of this investigation was to determine the outcome of limb amputation in wapiti. Medical records of 13 wapiti that underwent limb amputation were reviewed to determine age, weight, sex, injury preceding amputation, limb amputated, amputation location, length of hospital stay, complications, and outcome. Ages ranged from 3 months to 8 years and weights from 70 kg to 280 kg. All animals were female. Eleven animals sustained catastrophic long bone fractures prior to amputation. Five animals had front limb amputations and 8 had hind limb amputations. Of these animals, 1 with a front limb amputaiton and 5 with hind limb amputations survived. Postsurgical inability to stand is associated with hospitalization of > 1 day. Of the 13 wapiti reviewed, 5 with hind limb amputations have produced and reared offspring. Hind limb amputation can be considered a viable alternative to euthanasia when catastrophic orthopedic injuries occur in female wapiti.     

Idiopathic noncirrhotic portal hypertension in dogs: 33 cases (1982-1998)

OBJECTIVE: To describe clinical signs, diagnostic findings, and outcome in dogs with idiopathic intrahepatic portal hypertension. DESIGN: Retrospective study. ANIMALS: 33 dogs. PROCEDURE: Medical records of dogs with portal hypertension of intra-abdominal origin were reviewed. Dogs with intra-abdominal portal hypertension of vascular causes or with hepatic histopathologic changes consistent with severe diffuse hepatobiliary disease were excluded. History and results of physical examination, clinicopathologic tests, diagnostic imaging studies, histologic examination, and treatment were summarized. Outcome was determined in 26 dogs. RESULTS: Dogs were referred most often because of ascites, intermittent vomiting or diarrhea, and polydipsia of several months' duration. Microcytosis, high serum alkaline phosphatase and alanine transaminase activities, hepatic dysfunction, urine specific gravity < or = 1.021, and abdominal transudate were the predominant clinicopathologic features. Microhepatia, abdominal effusion, and multiple anomalous venous anastomoses were the major findings of diagnostic imaging. Hepatic histopathologic changes were consistent with idiopathic noncirrhotic portal hypertension and were indistinguishable from those of dogs with surgically created portocaval anastomosis. Outcome was determined for 19 dogs released from hospital; 13 dogs remained healthy with mostly palliative treatment for periods of 5 months to 9 years. CONCLUSIONS AND CLINICAL RELEVANCE: The clinical signs, clinicopathologic test results, portal pressure, and gross appearance of the liver of dogs with idiopathic noncirrhotic portal hypertension may be identical to those of dogs with cirrhosis; therefore liver biopsy is crucial. Because the prognosis for idiopathic noncirrhotic portal hypertension is generally favorable, owners of affected dogs should be discouraged from choosing euthanasia.     

Bilateral cavernous sinus syndrome in dogs: 6 cases (1999-2004)

OBJECTIVE: To determine clinical features, diagnostic imaging abnormalities, underlying disease, disease progression, and outcome in dogs with bilateral cavernous sinus syndrome. DESIGN: Retrospective study. ANIMALS: 6 dogs. PROCEDURE: Dogs were included if clinical signs consistent with bilateral cavernous sinus syndrome (i.e., deficits of the third, fourth, and sixth cranial nerves and at least 1 of the first 2 branches of the fifth cranial nerve) were present and a lesion of the cavernous sinus was identified by means of diagnostic imaging or postmortem examination. RESULTS: 5 dogs were evaluated because of problems referable to abnormal ocular motility or pupillomotor dysfunction, and 1 dog was evaluated because of partial motor seizures involving the face and bilateral mydriasis. Four dogs had neurologic signs referable to an extrasinusoidal lesion at the time of initial examination, and the remaining 2 dogs eventually developed extrasinusoidal signs. Besides neuroanatomic location, the only consistent neuroimaging feature was variably intense, heterogeneous enhancement of cavernous sinus lesions. Neoplasia was histologically confirmed as the underlying cause in 5 of the dogs and was suspected in the remaining dog. Median survival time for the 4 dogs that were treated was 199 days (range, 16 to 392 days). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that bilateral cavernous sinus syndrome is rare in dogs but should be suspected in dogs with compatible clinical signs. Affected dogs have a poor prognosis, and dogs with clinical signs of bilateral cavernous sinus syndrome should be systematically evaluated for neoplastic disease.     

Cystine-containing urinary calculi in dogs: 102 cases (1981-1989).

One hundred and seven cystine-containing urinary calculi from 1 female and 101 male dogs were analyzed. Cystine-containing calculi accounted for 2% (107 of 5,375) of all canine urinary calculi submitted to the urinary stone analysis laboratory from July 1981 through December 1989. Male dogs that formed cystine calculi were compared with 3 other canine populations to determine whether certain breeds were apparently at increased or decreased risk for cystine calculus formation. In one or more of 3 population comparisons, significantly increased risk of cystine calculus formation was found in Mastiffs, Australian Cattle Dogs, English Bulldogs, Chihuahuas, Bullmastiffs, Newfoundlands, Dachshunds, Basenjis, Australian Shepherd Dogs, Scottish Deerhounds, Staffordshire Terriers, Miniature Pinschers, pitbull terriers, Welsh Corgis, Silky Terriers, and Bichon Frises. Significantly low risk of cystine calculus formation was found in German Shepherd Dogs, Poodles, Schnauzers, and mixed-breed dogs.     

Hepatotoxicity of phenobarbital in dogs: 18 cases (1985-1989).

The medical records of 18 dogs that had hepatic disease and received phenobarbital as an anticonvulsant for 5 to 82 months were reviewed. Clinical signs included sedation and ataxia in all dogs, 5 dogs were also anorectic, 2 had coagulopathy, 3 were icteric, and 5 had ascites. Serum biochemical analysis revealed serum albumin concentration less than or equal to 2.2. g/dl in 12 dogs, serum alkaline phosphatase activity greater than or equal to 169 U/L in 18 dogs, serum alanine transaminase activity greater than or equal to 57 U/L in 15 dogs, and total bilirubin concentration greater than or equal to 1 mg/dl (in the absence of lipemia) in 7 dogs. Serum phenobarbital concentration was greater than or equal to 40 micrograms/ml in 12 of 17 dogs. Sulfobromophthalein excretion was prolonged in 8 of 10 dogs. Preprandial serum bile acid concentrations were high in 8 of 10 dogs, and 2-hour postprandial serum bile acid concentrations were high in 9 of 10 dogs. Two of 4 dogs tested had resting plasma ammonia concentrations greater than 200 mg/dl. An ammonia tolerance test was performed on 2 other dogs; both had ammonia concentration greater than or equal to 200 mg/dl in the plasma 30 minutes after receiving 100 mg of ammonium chloride/kg of body weight, PO. Nine dogs died, 1 was euthanatized, and necropsies were performed on these 10 dogs. Biopsies and necropsies of 6 dogs revealed chronic hepatic fibrosis with nodular regeneration (cirrhosis). One dog had hepatocellular carcinoma and mild cirrhosis. In 1 dog, after phenobarbital had been withheld, necropsy revealed complete recovery of the previously observed lesions.     

Results of root canal treatment in dogs: 127 cases (1995-2000)

OBJECTIVE: To evaluate results of root canal treatment in dogs. DESIGN: Retrospective study. SAMPLE POPULATION: 127 tooth roots in 64 dogs. PROCEDURE: Radiographs obtained before surgery, immediately after surgery, and during follow-up examinations after surgery were evaluated by 2 individuals. Treatment was considered successful if the periodontal ligament space was normal and possible preoperative root resorption, if present, had ceased. Treatment was considered to show no evidence of failure if possible preoperative root resorption had ceased but a preexisting periapical lesion had remained the same or only decreased in size and not complete resolved. Treatment was considered to have failed if a periapical lesion or root resorption developed subsequent to endodontic treatment, if a preexisting periapical lesion had increased in size, or if possible preoperative root resorption appeared to continue after endodontic treatment. RESULTS: Follow-up time ranged from 1 to 60 months (mean, 13 months). Treatment was classified as successful for 87 (69%) roots, as showing no evidence of failure for 33 (26%) roots, and as having failed for 7 (6%) roots. The success rate was lower for canine teeth than for maxillary fourth premolar teeth. Roots with a preexisting periapical lucency or preexisting root resorption had lower success rates. The use of intracanal medication and the method and quality of obturation were not associated with outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that root canal treatment offers a viable option for salvage of periodontally sound but endodontically diseased teeth in dogs.