PROGRESSIVE SYRINGOHYDROMYELIA AND DEGENERATIVE AXONOPATHY IN A BOBCAT (LYNX RUFUS) FOLLOWING SURGICAL CORRECTION OF A CHIARI-LIKE MALFORMATION.

A 3-yr-old male captive bobcat (Lynx rufus) presented with chronic ataxia and right-sided head tilt. Magnetic resonance imaging (MRI) revealed cerebellar crowding and compression consistent with Chiari-like malformation. The clinical signs did not improve after surgical occipital craniectomy, and 2 mo postoperatively a second MRI showed hydromyelia and continued cerebellar compression. The bobcat was euthanized, and necropsy showed chronic focal cerebellar herniation and chronic multifocal atlanto-occipital joint osteophyte proliferation. Histology confirmed the presence of a thick fibrous membrane along the caudal aspect of the cerebellar vermis, suggestive of postoperative adhesions, and axonal degeneration of the cervical spinal cord, even in sections without a central canal lesion. These lesions appear to have been complications associated with surgical correction of the Chiari-like malformation.