title: Double wall sign.
authors.affiliation: Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, No 325, Cheng-Kung Road, Sec 2, Neihu 114, Taipei, Taiwan, ROC. tsaishihung@yahoo.com.tw
authors.forename: S-H
authors.initials: SH
authors.lastname: Tsai
authors.forename: S-J
authors.initials: SJ
authors.lastname: Chu
authors.forename: S-J
authors.initials: SJ
authors.lastname: Chen
mesh_terms: D000368:Aged; D006801:Humans; D007422:Intestines / Q000000981:diagnostic imaging; D008297:Male; D011027:Pneumoperitoneum / Q000000981:diagnostic imaging*; D011860:Radiography, Abdominal / Q000379:methods