1. Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.
2. Department of Radiology, Catholic University of Daegu College of Medicine, Daegu 712-702, Korea.
3. Department of Radiology, Inje University College of Medicine, Busan Paik Hospital, Busan 614-735, Korea.
4. Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Korea.