1. Department of Radiology and Intervention, China-Japan Union Hospital of Jilin University, Changchun, China
2. Department of Anatomy, Tarim University School of Medicine, Alaer, China
3. Department of Gastrointestinal Colorectal and Anal Surgery, China-Japan Union Hospital of Jilin University, Changchun, China
4. Department of Intervention, Affiliated Hospital of Jinggangshan University, Jian, China
5. Department of Anatomy, Kunming Medical University, Kunming, China
6. Department of Gastrointestinal Surgery, Beijing Hospital, National Center of Gerontology; Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China