[1] Taipei City Hosp, Dept Radiol, Renai Branch, Taipei 106, Taiwan
[2] Changhua Christian Hosp, Er Lin Branch, Dept Radiol, Taipei, Taiwan
[3] Changhua Christian Hosp, Dept Gastroenterol, Taipei, Taiwan
[4] Natl Yang Ming Univ, Dept Biomed Imaging & Radiol Sci, Taipei 112, Taiwan