1. Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine; Utrecht University; PO Box 80.154, 3508 TD Utrecht The Netherlands
2. Department of Radiology, Faculty of Veterinary Medicine; Utrecht University; PO Box 80.154, 3508 TD Utrecht The Netherlands
3. Department of Pathology, Faculty of Veterinary Medicine; Utrecht University; PO Box 80.154, 3508 TD Utrecht The Netherlands