1. Department of Neuroradiology, Medical University Innsbruck
2. Department of Neuroradiology, University Hospital Giessen
3. Department of Radiology, University Hospital Giessen
4. Department of Neurosurgery, University Hospital Giessen
5. Department of Neurosurgery, Vogtland-Klinikum Plauen
6. Department of Neuroradiology, Klinikum Wuppertal