Pathological characteristic of the eye changes within dogs ophthalmopathy associated with paraneoplastic syndrome

Ophthalmopathy associated with parneoplastic syndrome is a poorly studied pathology of the dogs eye. They occur as a result of the malignant neoplasm’s systematic exposure on the animal's body. They appear in the form of non-specific clinical signs. Main objective of the study – to study the pathomorphological changes in the dog’s eyes with malignant neo-plasms. The material for the study were 30 eyeballs enucleated in dogs in the terminal stage of cancer. Autopsy material obtained from animals was subjected to standard histological processing. As a result of histological studies, pathomorphological changes in eyeball structures associated with Patnaik G2 and G3 mastocytomas (28.6% of cases), liver and kidney carcinomas (28.6%), lymphoma (28.6%) and spleen hemangiosarcoma (14.2%) were revealed in 46.7% of cases. The main histopathological changes were thickening of the iris due to inflammatory cellular infiltration (57.1%) and vasodilation of blood vessels (42.9%), the presence of fibrinous hemorrhagic exudate in the anterior chamber of the eye (28.6%), edema and inflammatory infiltration of the vascular membrane proper (42.9%), thinning, loss of layering and weak retinal atrophy (42.9%). The revealed histological changes indicate the predominant involvement in the pathological process of the vascular membrane of the eye with a violation of the hematophthalmic barrier, as the main pathogenetic mechanism for the development of endogenous uveitis against the background of malignant neoplasm in the animal body.