1. Department of Radiology and Biomedical Imaging; University of California; San Francisco California USA
2. Institut fuer diagnostische und interventionelle Radiologie, Technische Universitaet Muenchen; Munich Germany
3. Karl-Ruprecht Universitaet Heidelberg, Fakultaet fuer Medizin; Heidelberg Germany
4. Institute of Medical Statistics and Epidemiology, Technische Universitaet Muenchen; Munich Germany
5. Applied Science Laboratory; GE Healthcare; Waukesha Wisconsin USA