Common Radiological signs

Presented by Dr Laith fadhelMBchB, P.G.C.R

Hilum Overlay Signdifferentiates large pulmonary artery from hilar mass on chest x-ray; mass superimposes on vessels

Fat Pad Signelevation of extrasynovial, intracapsular fat around the elbow as a result of distension of the joint by an effusion, usually traumatic

David Letterman Signwidening of distance between the scaphoid and lunate (>3mm) on PA view from ligament disruption-AKA Terry Thomas sign

Onion Skin Periosteal Reactionlamellar reaction from concentric layers of new growth seen in Ewing's, osteomyelitis, and osteosarcoma

Codman's Triangletriangular elevation of periosteum from an aggressive, usually malignant, bone tumor such as an osteosarcoma

Oil Dropletsmultiple punched-out lytic defects seen in multiple myeloma

Cotton Wool Appearanceislands of poorly marginated sclerotic disease surrounded by less dense skull in Paget disease

Cobra Head Abnormalityrounded dilatation of distal ureter, surrounded by thin lucent line, seen in patients with adult-type ureteroceles

Mercedes Benz SignTri-radiate appearance of air in gallstone seen on CT and plain films

Omental Cakeplaque-like Neoplastic infiltration of the greater omentum most often caused by stomach, colon or ovarian carcinoma

Crescent Signappearance of a sliver of air usually best seen beneath the right hemi diaphragm in pneumoperitoneum

Falciform Ligament Signvisualization of usually invisible falciform ligament from surrounding air in pneumoperitoneum

Corkscrew Esophagusconstricted, twisted lumen usually seen in diffuse esophageal spasm from abnormal, tertiary contractions

Thumb printingindentation in contrast or air-filled bowel lumen caused by sub mucosal infiltration and resembling a thumbprint; e.g. ischemia

Cobblestone AppearanceGI-alternating normal and denuded mucosa from ulceration, esp. in Cohn's disease of the colon

Lead Pipe Colonrigid, ahaustral appearance of colon classically seen with chronic ulcerative colitis

Coffee-bean Signdilated sigmoid colon in sigmoid volvulus thought to resemble a giant coffee-bean

Colon Cutoff Signdilated transverse colon, usually to splenic flexure, associated with pancreatitis or ischemic colitis

Apple Coreappearance of an annular constricting carcinoma of the bowel, usually the colon, from circumferential involvement of lumen