2006 Volume 15 Issue 3 Pages 85-89
We treated a six-year-old male Shetland sheep dog with head tilting and difficulty in standing. MRI examination revealed an intracranial mass at the right cerebellopontine angle. Surgical removal of the mass was attempted six days after the first diagnosis. The right transverse sinus was exposed by suboccipital craniectomy, and plugged with bone wax. The plugged sinus and the surrounding bone tissues were removed, and the cerebellum was widely exposed. After incision of the dura on the cerebellum, the mass could be partially observed because it was sticking out of the parenchyma of the cerebellum. The mass was removed as much as possible with gentle dissection of the parenchyma, but on post-operative MRI images part of the mass was found still remaining inside the skull. Histopathologically, the mass was diagnosed as a choroid plexus papilloma. Recovery from the surgery was remarkable, and the dog was able to walk unaided within a week. The dog was in a satisfactory condition for 22 post-operative months although its head tilting persisted. It died because of recurrence of the disease 25 months after the first diagnosis.