1. Department of Radiology, University of Keimyung College of Medicine, Dongsan Medical Center, Daegu 700-712, Korea.
2. Department of Internal Medicine, University of Keimyung College of Medicine, Dongsan Medical Center, Daegu 700-712, Korea.
3. Department of Radiology, Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 158-736, Korea.