1. Department of Pediatrics and Adolescent Medicine, Division of Pediatric Hematology and Oncology, Medical Center—University of Freiburg, 79106 Freiburg, Germany
2. Neuroradiological Clinic, Klinikum Stuttgart, 70174 Stuttgart, Germany
3. Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147 Essen, Germany
4. Institute of Clinical Hemostaseology and Transfusion Medicine, Saarland University and University Hospital, 66424 Homburg, Germany