target sign

target sign

GI imaging A smoothly-contoured radiopacity with both central and peripheral radiolucency, which may be seen in pedunculated colonic polyps, when viewed en face by double contrast–air-contrast barium studies; an 'eccentric' target sign is seen in GI diverticuli where a small amount of radiocontrast enters the pouch and is surrounded by the radiopaque body of a diverticulum Lung imaging A circumscribed pulmonary aspergilloma or focus of necrotizing bronchopneumonia seen in a plain CXR. Cf Coin lesion.