Vascular malformations and hemangiomas of the canine spinal cord.

An arteriovenous malformation and two hemangiomas in the canine spinal cord were found in three dogs. The malformation was ventral, extramedullary and largely subdural. Chronic hypoxia, consequent upon the shunt, had led to extensive local edema, necrosis and hemorrhage at T13-L1. Prominent intramedullary perivascular fibrosis, mineralization and obliteration were the presumed consequences of the hemodynamic insult. The hemangiomas, one of which was multiple, were deep lesions that produced compressive changes in the adjacent cord tissue. The masses were regarded as benign neoplasms with central sclerosis. These conditions appear not to have been reported previously in the dog.