1. Department of Neurosurgery, University Hospital Bonn, Bonn, Germany
2. Department of Epileptology, University Hospital Bonn, Bonn, Germany
3. Ruhr-Epileptology, Ruhr-University Bochum, Knappschaftskrankenhaus Bochum, Bochum, Germany
4. Department of Neurosurgery, University Hospital Aachen, Aachen, Germany
5. Department of Neurosurgery, Gemeinschaftskrankenhaus Herdecke, Herdecke, Germany