title: Linear shadows in the air-contrast barium enema.
abstract: In 3 patients with carcinoma of the colon, lesions were seen as linear shadows on air-contrast barium enema studies. When the elevation of a lesion is slight or the tumor--mucosal interface is gently sloping, the tumor's proximal and distal edges may be ill-defined or disappear altogether. Thus only a linear shadow representing the interface between the tumor surface and air in the lumen appears. Other causes of these lines are also discussed.
mesh_terms: D000368:Aged; D000388:Air; D001466:Barium Sulfate; D002430:Cecal Neoplasms / Q000000981:diagnostic imaging*; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012811:Sigmoid Neoplasms / Q000000981:diagnostic imaging
chemical_list: D001466:Barium Sulfate