Chih-Sheng Huang1,2, Li-Kuo Huang3,4, Chien-Ho Tsai5,3. 1. Department of Surgery, National Yang-Ming University Hospital, Yilan, Taiwan. imalive20@hotmail.com. 2. School of Medicine, National Yang-Ming University, Taipei, Taiwan. imalive20@hotmail.com. 3. School of Medicine, National Yang-Ming University, Taipei, Taiwan. 4. Department of Radiology, National Yang-Ming University Hospital, Yilan, Taiwan. 5. Department of Surgery, National Yang-Ming University Hospital, Yilan, Taiwan.