Two cases of paradoxical vestibular syndrome in Rough Collies

Two cases of paradoxical vestibular syndrome are described. The principal clinical signs were a persistent head tilt to the right and a progressive ataxia in unrelated 6-year-old Rough Collies. In both dogs the primary lesion found post mortem was a papilloma of the choroid plexus of the fourth ventricle on the left side. This was associated with severe disruption of the cerebellar peduncles, cerebellar folia and the medulla oblongata adjacent to the tumour.