Choroid plexus tumors in the dog.

Clinical and necropsy records for nine dogs with tumors of the choroid plexus were reviewed. In seven of the dogs, the tumors were on the left side of the fourth ventricle. All of the dogs were males, ranging in age from 13 months to 9 years. Upper motor neuron tetraparesis and positional nystagmus were the most common neurologic signs. Less frequently recorded were head tilt, vomiting, bradycardia, and signs of cranial nerve dysfunction. Alteration in consciousness was evident in four of the dogs and ranged from personality changes to coma.

Necrotizing myelopathy secondary to embolization of herniated intervertebral disk material in the dog.

Seven dogs (3 Great Danes, 2 German Shepherd Dogs, 1 Weimaraner, and 1 Boxer) ranging in age from 1 1/2 to 9 years were examined because of acute neurologic signs involving the limbs. All dogs were nonambulatory--3 tetraparetic and 4 paraparetic. In each case, treatment was unsuccessful or not advised, and each dog was euthanatized. Necropsy revealed hemorrhagic infarcts of the gray and white matter as a result of fibrocartilaginous embolization in leptomeningeal and parenchymal vessels of the spinal cord. The emboli were derived from disk material herniated into the vertebral venous sinuses.

Primary tumors of the spinal cord and meninges in six dogs.

Primary spinal cord tumors were detected in 6 mature dogs. Two of the tumors were astrocytomas, 2 were meningiomas, and 2 were neurilemmomas. Five tumors were in the cervical portion and 1 was in the lumbar portion of the spinal cord.

Spinal cord compression caused by osteocartilaginous exostoses of the spine in two dogs.

Two dogs, one 4 months old and the other 1 year old, had histories of progressive posterior weakness. In both cases, there was severe asymmetric proprioceptive loss but appreciable preservation of strength. Benign, cystic expansile lesions involving the facets and lamina of the thoracic spine were observed radiographically; a single lesioons was demonstrated in the other. Examination of biopsy speciments taken at the time of laminectomy revealed the lesions to be osteocartilaginous exostoses (osteochondromas, ecchondromas, exostoses). The progress of dogs 1 and 2 has been monitored for 1 1/2 years and 9 months, respectively. Dog 1 has no weakness or proprioceptive loss; dog 2 has a mild proprioceptive loss in the right hindlimb.

Calcifying aponeurotic fibroma in a dog.

A calcifying aponeurotic fibroma involving the soft tissue and bone of the occipital area compressed and attenuated the cerebellum and brainstem of a 9-year-old female dog of mixed breeding. Clinical signs included a head tilt to the left; gait ataxia; anisocoria, with a midly dilated left pupil; horizontal nystagmus, with the fast phase to the right; and a mild depression of the level of consciousness. The signs were sequential and progressive.