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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Summary

Bronchoalveolar lavage (bal) was performed in 47 dogs with multicentric malignant lymphoma (ml). Cytologic results were evaluated, and ability to detect pulmonary involvement with ml, using bal, was compared with ability to detect pulmonary involvement, using thoracic radiography and tracheal wash. Lung lobes were considered to be involved with ml on the basis of bal fluid findings if morphologically abnormal lymphocytes were present in the fluid.

Total nucleated cell count, relative lymphocyte count, and absolute lymphocyte count were greater (P < 0.001) in bal fluid from dogs with multicentric ml than in bal fluid from histologically normal dogs. Pulmonary involvement with ml was detected by bal fluid cytologic examination in 89 of 135 lung lobes lavaged (66%). Lung lobes involved with ml were from 31 of the 47 dogs with multicentric ml (66%). Radiographic abnormalities supportive of pulmonary parenchymal involvement with ml were detected in 16 of the 47 dogs (34%). Of these 16 dogs, 15 (94%) had pulmonary involvement with ml on the basis of bal fluid cytologic findings. Tracheal wash fluid contained abnormal lymphocytes in 4 of 42 dogs (10%). In all 4 dogs, bal fluid also contained abnormal lymphocytes. Cytologic evaluation of bal fluid was more sensitive in detecting pulmonary involvement with ml, compared with radiographic evaluation of the lungs or tracheal wash.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate a technique for minimally invasive excisional brain biopsy and intracranial brachytherapy catheter placement in dogs.

Animals—5 healthy adult female dogs.

Procedures—Computed tomographic guidance was used to plan a biopsy trajectory to a selected area of brain with reference to a localizer grid. The procedure was performed through a 1-cm skin incision and 6-mm burr hole by use of a 9-gauge biopsy device. Five cylindrical samples (3 to 4 mm in diameter and 7 to 12 mm in length) were removed over 5 cycles of the vacuum-assisted tissue excision system, leaving approximately a 2-cm3 resection cavity. A balloon-tipped intracranial brachytherapy catheter was placed through the burr hole into the resection cavity, expanded with saline (0.9% NaCl) solution, and explanted 7 days later.

Results—4 of 5 dogs survived the procedure. The fifth died because of iatrogenic brain damage. Neurologic deficits were unilateral and focal. Twenty-four hours after surgery, all surviving dogs were ambulatory, 2 dogs exhibited ipsiversive circling, 4 had contralateral proprioceptive deficits, 3 had contralateral menace response deficits, 2 had a reduced contralateral response to noxious nasal stimulation, and 1 had dull mentation with intermittent horizontal nystagmus and ventrolateral strabismus. Neurologic status improved throughout the study period. Histologic quality of biopsy specimens was excellent.

Conclusions and Clinical Relevance—This technique enabled histologic diagnosis from high-quality biopsy specimens obtained through a minimally invasive technique and has potential applications for multimodal treatment of deep brain tumors in dogs.

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in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Summary

Signalment, tumor sites, clinicopathologic, radiographic, and ultrasonographic features, as well as treatment protocols and survival information, were evaluated for 10 dogs with a histologic diagnosis of giant cell variant of malignant fibrous histiocytoma. Common clinical findings included subcutaneous masses, weight loss, anorexia, and lethargy. Laboratory abnormalities included anemia, hypoalbuminemia, and high concentrations of serum hepatic enzymes. Radiography and ultrasonography were useful in staging the extent of metastasis. Seven dogs had tumor metastasis at the time of diagnosis. Two other dogs developed evidence of metastasis during the course of treatment. The most common sites of tumor involvement were subcutaneous tissues, lymph nodes, liver, and lungs. Treatment protocols included surgical resection, intraoperative radiotherapy, and chemotherapy. Median survival time of all dogs was 61 days. Median survival time of the 6 treated dogs was 161 days. Findings on necropsy revealed metastasis with multiple organ involvement. The giant cell variant of malignant fibrous histiocytoma was determined to be a highly metastatic neoplasm in dogs, which may be responsive to surgical excision, chemotherapy, or radiotherapy.

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in Journal of the American Veterinary Medical Association

SUMMARY

The growth hormone (gh) secretagogue activity of variable dosages of clonidine (16.5, 50, 150, and 450 μg/kg of body weight), given orally mixed with the daily food ration, was evaluated in young and old dogs. Significant (P < 0.05) increase in plasma gh concentration was detected at all dosages tested in young dogs and in response to all but the lowest dose tested in the old dogs fed the clonidine-containing diet. Old dogs had plasma gh concentration that exceeded that of young dogs when higher doses of clonidine were used.

A clonidine (100 μg/kg)-supplemented diet was fed to middle-aged dogs twice daily for 30 days. Significant (P < 0.01) increase of plasma gh concentration was observed on the first day of the feeding trial, but was undetectable by day 30. After feeding the clonidine-enhanced diet for 30 days, the effects on thymic morphology were variable, and there was no effect on plasma thymulin titer. Clonidine-fed dogs had significantly increased lymphocyte blastogenic responsiveness to mitogens, compared with that of control dogs, when evaluated as stimulation index.

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in American Journal of Veterinary Research