1. Department of Neurosurgery, University Hospital Bonn, 53127 Bonn, Germany
2. Center for Advanced Imaging Research, Department of Diagnostic Radiology and Nuclear Medicine, Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, MD 20742, USA
3. Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, 53127 Bonn, Germany
4. Department of Neuroradiology, University Hospital Bonn, 53127 Bonn, Germany
5. Department of Neurology, University Hospital Bonn, 53127 Bonn, Germany