1. Department of Gastroenterology and Hepatology, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.
2. Department of Surgery, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.
3. Department of Gastroenterology and Hepatology, Chonnam National University Hwasun Hospital, Chonnam National University Medical School, Hwasun, Korea.
4. Department of Thoracic and Cardiovascular Surgery, Chonnam National University Hospital, Chonnam National University Medical School, Gwangju, Korea.