1. Brandenburg Medical School Fontane, Campus Bad Saarow, Bad Saarow, Germany
2. Department of Neurosurgery, Helios Clinic Bad Saarow, Bad Saarow, Germany
3. Institute of Pathology, Helios Clinic Bad Saarow, Bad Saarow, Germany
4. Department of Otorhinolaryngology, Helios Clinic Bad Saarow, Bad Saarow, Germany
5. Department of Neurosurgery, Helios Clinic Krefeld, Krefeld, Germany
6. Department of Neurosurgery, Winterthur Cantonal Hospital, Wintherthur, Switzerland
7. Faculty of Health Sciences, Joint Faculty of the Brandenburg University of Technology Cottbus, Senftenberg, The Brandenburg Medical School Theodor Fontane, and the University of Potsdam, Germany