1. Department of Radiation Oncology, China Medical University Hospital , Taichung , Taiwan
2. Department of Biomedical Imaging and Radiological Sciences, China Medical University , Taichung , Taiwan
3. Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University , Taipei , Taiwan
4. School of Medicine, College of Medicine, China Medical University , Taichung , Taiwan
5. School of Medicine, College of Medicine, Taipei Medical University , Taipei , Taiwan