1. From the Department of Radiology, Nihon University School of Dentistry at Matsudo, 2-870-1 Sakaecho-Nishi, Matsudo, Chiba 271-8587, Japan (K.I., N.H., H.M., S.O., T. Kondo, T. Kaneda); and Departments of Radiology (V.C.A.A., O.S.), Otolaryngology–Head and Neck Surgery (O.S.), and Radiation Oncology (O.S.), Boston Medical Center, Boston University School of Medicine, Boston, Mass.