Signalment:4-year-old spayed female Labrador retriever
History:A 4-year-old spayed female Labrador retriever initially presented for vision loss, characterized by running into walls and lack of awareness of surroundings. Fundic examination at that time revealed bilateral foci of retinal separation. The dog was started on doxycycline, amlodipine, and a short tapering dose of prednisone with no apparent improvement in vision. About two weeks after the onset of clinical signs, she started to appear painful and became very lethargic. She developed severe ataxia, which rapidly progressed (within a few days) to non-ambulatory tetraparesis with delayed to absent conscious proprioception in all four limbs (left > right). Other abnormalities on neurologic exam included dull mentation, absent menace response OU, positional rotary nystagmus OU (fast phase to the left), and miosis OU with intact pupillary light reflex OU. While hospitalized in the clinic, she became hypertensive and progressively bradycardic, presumably in response to increased intracranial pressure (Cushing reflex). Due to the dog’s rapid clinical decline, humane euthanasia was elected.