1. Department of Radiology and Biomedical Imaging, Yale School of Medicine, New Haven, CT 06510, USA
2. Medical Faculty, Ludwig-Maximilians-University of Munich, 80336 Munich, Germany
3. Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, USA
4. Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06510, USA
5. Department of Neurology, Yale University School of Medicine, New Haven, CT 06510, USA