1. Department of Radiotherapy, Hong Kong Sanatorium and Hospital
2. Department of Radiology, The University of Alabama at Birmingham, Birmingham, Alabama
3. Department of Medicine, University of Otago, Dunedin, New Zealand
4. Department of Radiology, Duke University, Durham, North Carolina, USA
5. Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong