SPINAL CORD COMPRESSION CAUSED BY A METASTATIC LESION FROM AN AORTIC BODY TUMOUR

An aortic body tumour in a 7-year-old wire-haired fox terrier with hind limb ataxia is described. A metastatic lesion in the dorsal arch of the eighth thoracic vertebra caused compression of the spinal cord. Radiographic techniques are discussed that enabled the position and extent of the primary tumour and its metastasis to be defined and allowed a provisional diagnosis of chemodectoma.     

A MIXED TUMOUR AND AN ADENOMA BOTH OF CERUMINOUS GLAND ORIGIN IN A DOG

Ceruminous gland tumours are uncommon in the dog and this paper reports a case of two such tumours which arose in either ear of a 12 year old male long-haired Dachshund. Histologically, one tumour was a ceruminous adenoma and the other a rare ceruminous mixed tumour of borderline malignancy.     

FUNCTIONING ADRENOCORTICAL TUMOUR IN A DOG

Naturally-occurring hyperadrenocorticism was diagnosed in an 11-year-old female Dachshund with signs of polydipsia, polyuria, pendulous abdomen, weakness, depression and lethargy, and laboratory test abnormalities comprising lymphocytopaenia, eosinopaenia, hypercholesterolaemia and increased plasma alkaline phosphatase concentration. While awaiting hormonal test results, an adrenocorticolytic drug (o,p'-DDD) was administered for 14 days, during which the patient deteriorated. Hormonal assays suggested a functioning adrenocortical tumour, but the poor condition of the patient precluded adrenalectomy. An adrenocortical carcinoma with hepatic metastases was found at necropsy.     

TUMOUR ASSOCIATED ANTIGENS IN BOVINE HORN CANCER

SUMMARY: Tumour associated antigens in bovine horn cancer (HC) were demonstrated by immunodiffusion in agar gel and by immuno-fluorescence. Antiserums raised in/rabbits against sonicated pooled horn cancer tissue extracts and absorbed with normal antigens, reacted only with HC extracts on agar gel diffusion. Preparations of normal antigen (skin, horn core epithelium, lymph node and liver) and extracts from other tumours (fibroma, fibrosarcoma and myxoma) did not show any reactivity against absorbed antiserum in this test, the absorbed antiserum showing specific reactivity to HC extracts in gel diffusion tests was conjugated to fluorescein isothiocyanate. Many different HC, normal cells and cells from other tumours were incubated with the conjugate and examined by fluorescent microscopy. HC cells showed specific beaded fluorescence on the surface whereas such fluorescence was not observed in normal cells or cells from other tumours.     

SYSTOLIC AORTIC VALVE FLUTTER IN 6 DOGS

Systolic aortic valve flutter was identified by M-mode echocardiography in 6 large-breed dogs without evidence of structural cardiac disease. It ranged in amplitude, timing, and frequency. Systolic aortic valve flutter is considered an incidental and normal finding in some dogs, similar to the situation in humans.     

AORTIC AND CARDIAC MINERALIZATION IN THE DOG

Aortic and cardiac mineralization was found in 21 of 3443 (0.61%) canine thoracic radiographs. In none of 786 feline thoracic radiographs reviewed were such lesions present. Mineralizations were superimposed on the ascending aorta (19 dogs) or on the caudal cardiac silhouette (2 dogs). In 2 of 4 dogs mineralization was identified echocardiographically dorsal to the aortic valve in close proximity to coronary arteries. Computed tomography confirmed mineralization of the aortic arch and root in 2 of 2 dogs. Necropsy and histopathologic examination in 1 dog revealed multiple nodular aortic tunica media calcifications with adjacent areas of degeneration. Lesions were significantly overrepresented in older dogs and in Rottweilers, and regarded as dystrophic calcification, caused either by age-related degenerative changes or chronic disease-related processes. There was no evidence of clinical significance attributed to the mineralization in any dog. Aortic and cardiac mineralization should be recognized as an incidental, non-significant finding in dogs of advanced age and differentiated from pleural and pulmonary structures.     

DIAGNOSIS OF AORTIC THROMBOEMBOLISM IN TWO DOGS WITH RADIONUCLIDE ANGIOGRAPHY

Radionuclide angiography was used to document occlusion of the distal aorta by thromboemboli in two dogs. Findings were confirmed by necropsy. The location of the thrombus corresponded with the scintigraphic lesion. Information obtained by the radionuclide angiogram was instrumental in patient management. We suggest the use of radionuclide angiography as a quick, non-invasive alternative to contrast angiography in animals suspected of having aortic thromboembolism.     

CYSTIC ENDOMETRIAL HYPERPLASIA AND BACTERIAL ENDOMETRITIS ASSOCIATED WITH AN INTRAUTERINE FOREIGN BODY IN A GUINEA PIG WITH OVARIAN CYSTIC DISEASE

A 3-year-old, 920 g intact female guinea pig presented with a 4-month history of nonpruritic hair loss on the ventral abdomen. The physical examination revealed flank and ventral abdominal alopecia, mucoid vulvar discharge, and abdominal distension. Bilateral rounded masses just caudal to the kidneys and structures consistent with enlarged uterine horns were detected on abdominal palpation. Abdominal ultrasound revealed bilateral ovarian cysts, thickened uterine horns, and multiple circular hypoechoic and anechoic structures in the uterine wall. The patient underwent ovariohysterectomy. Gross examination of the uterus revealed a piece of hay in the left uterine horn. A final diagnosis was hormonally active ovarian follicular cysts, cystic endometrial hyperplasia, and purulent bacterial endometritis caused by Escherichia coli, Fusobacterium nucleatum, and Arthrobacter spp. Cystic endometrial hyperplasia is infrequently reported in guinea pigs, and this report describes an associated bacterial endometritis and uterine foreign body with concurrent ovarian cysts.     

IMAGING DIAGNOSIS—AORTIC THROMBOEMBOLISM ASSOCIATED WITH SPIROCERCOSIS IN A DOG

An 8-year-old neutered female Rhodesian Ridgeback developed acute, nonneurological right pelvic limb lameness. Femoral pulsation was poor, and oscillometric blood pressure measurements between the two pelvic limbs differed markedly. A caudal aortic right external iliac embolus was detected sonographically. Radiographically, there was a caudal esophageal mass and thoracic vertebral spondylitis typical of spirocercosis. Using CT-angiography, a caudal thoracic aortic aneurysm with a mural thrombus was detected. The dog recovered following heparin and aspirin therapy but signs recurred 7 months later. Subsequently, the patient improved on treatment and remains asymptomatic. This report illustrates the value of CT-angiography in detecting aortic thrombosis in dogs with spirocercosis.     

RADIOGRAPHIC FEATURES OF AORTIC BULB/VALVE MINERALIZATION IN 20 DOGS

The radiographic features of aortic bulb/valve mineralization in 20 dogs were reviewed. Extent, shape, number, and location of mineralization were recorded. Five of the dogs had additional alternate imaging examinations, including bone scintigraphy, echocardiography, and thoracic computed tomography. A necropsy was done on one dog, and the area of mineralization was evaluated using routine histology. The median age was 10 (mean 9.7; SD +/- 2.7) years. There were five males, seven neutered males, one female, and seven neutered females. The breeds were: Irish setter (6); rottweiler (7); chow-chow (1); miniature dachshund (1); borzoi (1); English setter (1); English springer spaniel (1); great Dane (1); and greyhound (1). Dogs with both right and left lateral radiographs (n = 17) had mineralization visible on both views, more conspicuously on the right lateral radiograph (n = 12). Aortic bulb mineralization was identified on the ventrodorsal radiograph of only one dog. On lateral radiographs, the aortic bulb mineralization was localized within the 4th intercostal space and in the craniodorsal quadrant of the cardiac silhouette. In nine of the dogs, there were complex or multiple mineralizations and in 11 dogs, there was a single curvilinear mineral opacity oriented in a caudoventral to craniodorsal direction. In all radiographs, the mineralization was in the expected position of the aortic bulb, and echocardiography (n = 4), spiral computed tomography (n = 2), and necropsy (n = 1) confirmed that the mineralization was within the aortic bulb. Clinical pathologic data of the dogs suggested no reason for metastatic mineralization. Exact etiopathogenesis of the lesions were not determined in this study. Based on the histologic findings in one dog, the mineralization seen in the aortic root is similar to a form of dystrophic mineralization called Monckeberg's calcific arteriosclerosis in humans. No clinical signs attributable to the mineralization were observed.     

COMPUTED TOMOGRAPHIC ASSESSMENT OF BODY FAT IN BEAGLES

Obesity is the most common nutritional disorder in small animals. To establish a computed tomographic (CT) method for assessment of visceral and subcutaneous fat content in the dog, CT analysis was performed in normal and obese beagles. Fat area was measured by the level detection method at varied attenuation ranges and compared with body fat content estimated by the deuterium oxide dilution method. Fat area measured at L3 using the attenuation range of -135/-105 Hounsfield unit had the best correlation with body fat content (r = 0.98). Regional fat distribution was almost the same between normal and obese dogs, with more fat accumulation at L1-S1 than T10-T13. Moreover, visceral and subcutaneous fat area could be estimated separately. This CT method may contribute to both the clinical diagnosis and the study of canine obesity, especially for studies in the relationship between body fat distribution and obesity-associated diseases.