1. From the Applied Imaging Science Laboratory, Department of Radiology, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA (K.K.K., E.G., F.J.R.); Department of Cardiology (T.K.) and Department of Radiology (M.A.), Takase Clinic, Takasaki, Japan; and Department of Epidemiology, Harvard School of Public Health, Boston, MA (H.K.).