Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA. dlrubin@stanford.edu|Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA. dlrubin@stanford.edu|Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA. dlrubin@stanford.edu|Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA. dlrubin@stanford.edu|Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA. dlrubin@stanford.edu