1. Department of Neurosurgery, University Hospital Olomouc, 77900 Olomouc, Czech Republic
2. Department of Paediatric Neurology, University Hospital Ostrava, 70852 Ostrava, Czech Republic
3. Department of Paediatric Oncology, University Hospital Brno, 66263 Brno, Czech Republic
4. Department of Paediatrics, University Hospital Olomouc, 77900 Olomouc, Czech Republic