1 Department of Radiology, Iwate Medical University School of Medicine, 2-1-1 Idaidori, Shiwa-Gun, Yahaba City, Iwate Prefecture, 028-3695, Japan. a.akahane@gmail.com.
2 Division of Central Radiology, Iwate Medical University Hospital, Shiwa-Gun, Yahaba City, Japan.
3 Department of Radiology, Iwate Medical University School of Medicine, 2-1-1 Idaidori, Shiwa-Gun, Yahaba City, Iwate Prefecture, 028-3695, Japan.