Objective—To determine whether cyclooxygenase-2 (COX-2) is expressed in benign or malignant canine uveal melanocytic neoplasms and whether expression correlates with malignancy.
Sample Population—Tissue sections from 71 globes; 57 with benign (n = 15), malignant (34), or mixed (8) uveal melanocytic neoplasms; 10 with nonneoplastic disease; and 4 with no abnormalities.
Procedures—Bleached sections from all globes and canine kidney were incubated with mouse monoclonal antibody directed against rat COX-2 protein or mouse antibody isotype control. Location, intensity, and percentage of immunolabeled cells were scored.
Results—Expression of COX-2 was detected in all but 5 globes, all of which contained neoplasms. Expression of COX-2 was detected in regions infiltrated by neoplasia in 21 globes; however, definitive labeling of tumor cells was detected in only 2 of those. In the remaining 19 globes, COX-2 expression was detected in areas also labeled in globes without disease and globes with nonneoplastic disease, especially the aqueous outflow tract and ciliary body. However, only globes with uveal malignant melanomas had detectable COX-2 expression in the iris. Expression of COX-2 was detected in the ciliary body of more globes with uveal malignant melanoma (20/34) than in those without disease (1/4), with nonneoplastic disease (4/10), or with melanocytoma (3/15) or mixed neoplasms (3/8).
Conclusions and Clinical Relevance—Canine globes with uveal melanocytic neoplasia appeared to express COX-2 in similar sites and with similar intensity as globes without neoplasia. Differentiation of benign from malignant canine uveal melanocytic neoplasms was not possible.
Objective—To describe clinical and diagnostic imaging features of zygomatic sialadenitis in dogs.
Design—Retrospective case series.
Animals—11 dogs with zygomatic sialadenitis and 20 control dogs without evidence of retrobulbar disease.
Procedures—Medical records were searched for dogs with zygomatic sialadenitis that underwent some combination of magnetic resonance imaging (MRI), computed tomography (CT), and ultrasonography. Signalment, clinical signs, results of clinicopathologic tests, cytologic and histologic diagnosis, treatment, qualitative disease features, and disease course were recorded. Images obtained via MRI or CT were analyzed for pre- and postcontrast signal intensity or density, respectively; zygomatic salivary gland area was determined. Results were compared with those of control dogs that underwent the same imaging procedures (n = 10/method). Ultrasonographic images of affected dogs were assessed qualitatively.
Results—Most (9/11) affected dogs were medium- or large-breed males (mean age, 8 years) with unilateral disease. Affected dogs had clinical signs of retrobulbar disease and cytologic or histologic evidence of zygomatic sialadenitis. Sialoceles were detected in 7 affected glands. Compared with values for control dogs, MRI findings in affected dogs (n = 7) included gland enlargement, T1-weighted hypointensity, T2-weighted hyperintensity, and increased contrast enhancement; CT features in affected dogs (2) included gland enlargement and hypodensity on unenhanced images. Retrobulbar masses were identified via ultrasonography in 9 of 10 orbits examined, and zygomatic salivary gland origin was detected in 4.
Conclusions and Clinical Relevance—Visualization of anatomic structures for diagnosis of zygomatic sialadenitis and evaluation of adjacent structures was excellent via MRI and CT Ultrasonography was less definitive but useful for sample collection.
Objective—To determine the incidence of and risk
factors for ventilatory failure in dogs undergoing
surgery for treatment of cervical spinal disorders and
to document ventilator management, clinical course,
and long-term outcome of dogs that experienced ventilatory
failure in association with cervical spinal disorders
or their management.
Procedure—Dogs with cervical spinal disorders that
required positive-pressure ventilation (PPV) were
identified, and signalment, concurrent diseases, neurologic
status at initial examination, clinical course,
pulmonary function before, during, and after PPV,
management techniques, complications, and outcome
were recorded. Dogs that underwent surgery
and required PPV were compared with dogs that
underwent cervical spinal surgery during the same
period that did not require PPV.
Results—14 dogs with cervical spinal disorders
required PPV to treat hypoventilation, including 13 of
263 (4.9%) dogs that underwent surgery for cervical
spinal disorders. Lesions between the second and
fourth cervical vertebrae and treatment by means of a
dorsal decompressive laminectomy were associated
with a significantly increased risk of perioperative
hypoventilation. Pulmonary gas exchange function was
normal or nearly normal throughout the course of PPV
in dogs that survived. Ten dogs survived, and 9 of the 10
regained neurologic function. All 9 dogs that regained
neurologic function had deep pain perception on initial
examination at the veterinary teaching hospital.
Conclusions and Clinical Relevance—Results suggest
that a small percentage of dogs with cervical
spinal disorders may require perioperative ventilatory
support. With prolonged PPV and aggressive management,
a good outcome may be achieved in dogs
similar to those described in the present study. (J Am
Vet Med Assoc 2001;218:1598–1602).