1. Department of Gastroenterological Surgery and Hernia Center, Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510655, P.R. China
2. Department of Ultrasonography, The Third Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510630, P.R. China
3. College of Traditional Chinese Medicine, Southern Medial University, Guangzhou, Guangdong 510515, P.R. China