A 4-year-old 1.18-kg (2.6-lb) spayed female Yorkshire Terrier was referred to the University of Illinois Veterinary Teaching Hospital for neurologic evaluation. The dog had been losing vision and circling to the right for 6 months. The dog became ataxic and unable to right itself after falling 1 week prior to referral.
Clinical and Gross Findings
On neurologic examination, the dog had a left head turn and tilt, thoracolumbar kyphosis, and extensor rigidity of the pelvic limbs. The dog was nonambulatory and tetraparetic and would twist and roll (ie, alligator roll) to the left when attempting to stand. Placing responses