1. Department of Radiology, UC Davis, Sacramento, CA, USA
2. University of California Davis Medical Center, Sacramento, CA, USA
3. Department of Neurology, University of California Davis Medical Center, Sacramento, CA, USA
4. Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, USA
5. Department of Medicine, UC Davis, Sacramento, CA, USA
6. Department of Radiology, University of Southern California, Los Angeles, CA, USA
7. Department of Radiology, University of California Davis Medical Center, Sacramento, CA, USA
8. School of Medicine in Saint Louis, Washington University, St Louis, MO, USA
9. Department of Radiology, Medical College of Wisconsin, Milwaukee, WI, USA