SIGNS IN RADIOLOGY

• Accordion sign : Appearance of bowel that may be seen with pseudomembranous colitis.


• Air crescent sign : Appearance of cavitation that may be seen with invasive apergillosis (see also Monod sign).


• Anteater’s nose sign : Sign of calcaneonavicular tarsal coalition.


• Apple Core lesion : Circumferential narrowing of the lumen secondary to colon cancer.


• Ball on tee sign : Sign of papillary necrosis on IVU.


• Banana sign : Seen on antenatal US and refers to a banana-shaped configuration of the cerebellum. Associated with neural tube defects.


• Bat wing appearance (chest) : Classic chest radiography finding for pulmonary edema.


• Bat wing appearance (neuro) : Appearance of 4th ventricle that may be seen with Joubert syndrome.


• Bergman’s coiled catheter sign : Sign of ureteral transitional cell carcinoma when a catheter coils in region of neoplasm (see also Goblet sign).


• Bird’s beak : Narrowing of the esophagus in achalasia.


• Bird’s beak sign or bird of prey sign : Narrowing of the colon in cecal volvulus.


• Blade of grass : Paget disease.


• Bone in bone sign : Appearance of spine that may be seen osteopetrosis.


• Boot-shaped Heart : Appearance of heart that may be seen with tetralogy of Fallot.


• Boxcar ventricles : Appearance of frontal horns that may be seen in Huntington’s disease.


• Bracket Calcification  : Corpus Callosum Lipoma


• Breast in a breast : Term used to describe Fibroadenolipomas.


• Bulging fissure sign : Bulging of a pulmonary fissure. Most commonly associated with Klebsiella pneumonia.


• Bullet carpal bones : Appearance of carpal bones that may be seen with mucopolysaccharidoses.


• Butterfly vertebrae : Results from failure of fusion of the lateral halves of the vertebral body because of persistent notochondal tissue between them.


• C sign : Sign of talocalcaneal tarsal coalition.


• Cake kidney : All renal tissue is fused into one pelvic mass and gives rise to two separate ureters which enter the bladder in normal relationship.


• Canoe paddle ribs : Appearance of ribs that may be seen with mucopolysaccharidoses.


• Celery stalking : Irregular appearance of metaphyses in patients with rubella. Also used to describe metaphyses in patients with osteopathia striata.


• Central dot sign : Sign of Caroli’s disease.


• Champagne sign : Specific but not commonly seen ultrasound finding for emphysematous cholecystitis.


• Cloverleaf skull : Appreance of the skull that may be seen with thanatophoric dysplasia.


• Cluster of grapes : Appearance that may be seen with pneumatosis cystoides coli.


• Cobra head sign : Dilatation of the distal ureter which may be seen in patients with ureteroceles.


• Coffee bean sign : Sigmoid volvulus.


• Collar sign : Sign of diaphragmatic rupture.


• Comet sign : Sign to differential a phlebolith from a ureteral stone. Calcified phlebolith represents the comet nucleus and the adjacent, tapering, noncalcified portion of the vein is the comet tail (also see soft-tissue rim sign).


• Comet tail sign : Produced by the distortion of vessels and bronchi that lead to an adjacent area of round atelectasis.


• Cord sign : Sign of intracranial dural sinus thrombosis.


• Corkscrew collaterals : Appearance of collaterals that may be seen in patients with Buerger disease.


• Corkscrew sign : Upper GI series sign of midgut volvulus.


• Corduroy appearance : Appearance of thickening trabeculations seen in intraosseous hemangiomas of the spine. See also polka-dot pattern.


• Crazy-paving sign : Nonspecific appearance consisting of linear network or reticular pattern with areas of ground-glass opacification. Classically associated with pulmonary alveolar proteinosis.


• Crossover sign : Anterior acetabular rim is projected laterally relative to the same point of the posterior rim in the superolateral aspect of the acetabulum. See with pincer type femoroacetabular impingement.


• Cyclops lesion : May occur status post anterior cruciate ligament reconstruction.


• David Letterman sign : :Sign of scapholunate ligament disruption (also see Terry Thomas sign).


• Dense vessel sign : Sign of cerebrovascular accident that represent thrombus in the middle cerebral artery.


• Dependent viscera sign : Sign of diaphragmatic rupture (viscera falls to a dependent position).


• Dot and dash pattern : Sacral insufficiency fracture.


• Double bleb sign : Appearance of amnion and yolk sac at 5-6 weeks. Embryo lies between amnion and yolk sac


• Double bubble sign : Sign of duodenal atresia and other forms of duodenal obstruction.


• Double decidua sign : Sign of early normal intrauterine gestation.


• Double density sign (cardiac) : Sign of left atrial enlargement when right side of the left atrium pushes into the adjacent lung.


• Double density sign (Nucs) : Pattern of uptake that may be seen on bone scans in patients with osteoid osteomas.


• Double duct sign : Simultaneous dilatation of the common bile and pancreatic ducts that is generally caused by a tumor in the pancreatic head.


• Double PCL sign : MRI sign of a bucket-handle meniscal tear.


• Double track sign : :Appearance of hypertrophic pyloric stenosis that may be seen on upper GI series.


• Draped aorta sign : Sign of contained rupture of an abdominal aoric aneurysm.


• Drooping lily sign : Inferolateral displacement of the opacified lower pole moiety in a duplex kidney from an obstructed (unopacified) upper pole moeity.


• Egg on a string : Appearance of the heart that may be seen with transposition of great arteries.


• Empty delta sign : Sign of intracranial dural sinus thrombosis.


• Epicardial fat pad sign : Sign of a pericardial effusion.


• Eye of the tiger sign : low signal intensity circumscribing the globus pallidus in patients with Hallervorden-Spatz syndrome.


• Faceless kidney : Appearance of kidney secondary to any process that obliterates renal sinus (i.e. lymphoma, transitional cell carcinoma).


• Fallen fragment sign : Sign of a pathologic fracture seen with unicameral bone cysts.


• Feeding vessel sign : Sign of pulmonary septic emboli.


• Flame shaped (Breast) : Gynecomastia.


• Flame shaped (MSK) : Paget disease.


• Fat halo sign : Seen in various diseases of the bowel in which fatty infiltration of the submucosa is present.


• Fat ring sign : Preservation of the perivascular fat around the mesenteric vessels that may be seen with mesenteric panniculitis.


• Flat tire sign : Sign of a ruptured globe.


• Flat waist sign : Appearance of left heart border that may be seen with left lower lobe atelectasis.


• Figure 3 sign : Appearance of the aorta that may be seen in patients with coarctation of the aorta.


• Figure of eight : Appearance of the brain in pachygyria.


• Finger in glove sign : Sign of mucous plugging seen with allergic bronchopulmonary aspergillosis.


• Fish vertebrae : Description of shape of vertebral bodies that may be seen in patients with sickle cell disease. See also: H-shaped vertebral bodies.


• Football sign : Sign of pneumoperitoneum seen on supine radiographs.


• Gastrointestinal string sign : Sign of Crohn disease.


• Goblet sign : Sign of ureteral transitional cell carcinoma that may be seen on retrograde or intravenous urography (see also Bergman’s coiled catheter sign).


• Gull wing appearance : Appearance of erosions that may occur in patients with erosive osteoarthritis.


• H-shaped vertebral bodies : Shape of vertebral bodies that may be seen in patients with sickle cell disease. See also: Fish vertebrae.


• Halo sign : Ground-glass attenuation surrounding a pulmonary nodule or mass on CT images. Represents hemorrhage and is highly suggestive of Aspergillus.


• Hampton’s hump : Triangular opacity secondary to infarction in the periphery of the lung distal to a pulmonary embolism.


• Head cheese sign : Sign of subacute hypersensitivity pneumonitis.


• Hidebound sign : On small bowel series, crowding of folds in dilated loops of small bowel may be seen in patients with scleroderma.


• High-attenuating crescent sign : Sign of impending abdominal aoric aneurysm rupture.


• Hole within a hole : Appearance that may be seen when eosinophilic granuloma involves the skull.


• Holly leaf appearance : Chest radiograph finding that may be seen with asbestos pleural plaques.


• Honda sign : Sacral insufficiency fracture.


• Hot cross bun sign : May be seen on axial T2 weighted images of the pons in multiple system atrophy.


• Hot nose sign : Sign that may be observed on brain flow scans in patients with brain death.


• Hourglass appearance : MRI appearance that may be seen with concentric cystic adventitial disease.


• Interstitial line sign : Sign that may be seen with an interstitial ectopic pregnancy.


• Inverted Napoleon’s hat sign : Sign of severe spondylolisthesis at the lumbosacral junction.


• Ivory vertebra sign : Increase in opacity of a vertebral body that retains its size and contours, with no change in the opacity and size of adjacent intervertebral disks.


• Juxtaphrenic peak sign : Tenting of the diaphragm that may be seen with right upper lobe atelectasis.


• Keyhole sign : US appearance that may be seen with posterior urethral valves.


• Lace like : Pattern that may be seen with sarcoid arthropathy.


• Lace-like pattern : Ultrasound appearance of hemorrhagic ovarian cysts.


• Lacunar skull : Appearance of skull that may be seen in infants with Chiari II malformation.


• Lambda sign : On a Gallium-67 citrate scan, uptake in the hilar and paratracheal lymph nodes gives the appearance of a lambda. This is seen in sarcoidosis.


• Lead pipe : Narrowing of colon with loss of haustra that may be seen in patients with ulcerative colitis.


• Linguine sign : MRI sign that may be seen in patients with intracapsular breast implant rupture.


• Lobster claw sign : Sign of papillary necrosis on IVU.


• Lollipop : Appearance of diverticula that may been seen on HSG in patients with adenomyosis.


• Luftsichel sign : “Air cresent”. Sign that may be seen with left upper lobe atelectasis.


• Mark Morton sign : Throckmorton’s sign with a small penis.


• Mercedes Benz sign : Appearance of gas within gallstones.


• Moulage sign : Effaced loop of bowel that may be seen on a small bowel series in sprue.


• Molar tooth sign (GU) : Perivesicular extravasation of contrast on CT cystogram in a patient with extraperitoneal bladder rupture.


• Molar tooth sign (Neuro) : Enlarged and horizontally directed tubular structure on each side of the midline emerging from the midbrain in patients with Joubert syndrome.


• Monod sign : Air surrounding an aspergilloma (Also see air crescent sign).


• Mount Fuji sign : CT sign of tension pneumocephalus.


• Naclerio’s V sign : V shaped lucency that may be seen over the left lower mediastinium in pneumomediastinum.


• Nipple sign : Appearance of hypertrophic pyloric stenosis that may be seen on ultrasound.


• Nubbin sign : Reflux nephropathy involving the lower pole of a duplicated collecting system.


• Nutmeg liver : Pattern of liver enhancement seen with passive congestion.


• Onion ring appearance : US appearance that may be seen with a testicular epidermoid cyst.


• Paintbrush appearance : Linear striations of contrast material opacifing collecting tubules that may be seen with medullary sponge kidney.


• Panda sign : On a Gallium-67 citrate scan, uptake in the lacrimal and salivary glands gives the appearance of a panda. This is suggestive of sarcoidosis.


• Parallel track sign : Pattern of uptake that may be seen on bone scan in patients with hypertrophic osteoarthropathy.


• Pear-shaped bladder : Bladder assumes the shape of a pear when it undergoes extrinsic compression due to excess tissue in the pelvis.


• Pearl necklace sign : MRI sign that may be seen with adenomyomatosis.


• Pencil in cup deformity : Erosion pattern of digits that may be seen in patients with psoriatic arthritis.


• Picture frame vertebral body : Thicken cortex of vertebral bodies that may be seen in patients with Paget disease.


• Picket fence : Appearance of bowel that may be seen on small bowel series with Whipple disease or gastrointestinal amyloidosis.


• Pistol grip deformity : Appearance of the proximal femur that may be seen with cam type femoroacetabular impingement.


• Playboy bunny sign : US sign of the appearance of the confluence of the hepatic veins with the IVC.


• Polka-dot pattern : Appearance of thickening trabeculations seen in intraosseous hemangiomas of the spine. See also Corduroy appearance.


• Porcelain gallbladder : Calcification of the gallbladder wall.


• Putty kidney : Appearance that may be seen with end-stage renal tuberculosis.


• Reversal sign : CT sign of anoxic brain injury where gray matter is lower in attenuation that white matter (the opposite is normal).


• Reversed halo sign : Relatively specific sign of pulmonary nodules in cryptogenic organizing pneumonia.


• Ribbon bowel : Appearance of bowel that may be seen on barium studies in graft versus host disease.


• Ribbon ribs : Appearance of ribs that may be seen with neurofibromatosis 1.


• Rice kernel : CT appearance that may be seen with dacryolithiasis.


• Rigler’s sign : Sign of pneumoperitoneum where both sides of a loop of bowel are outlined by air.


• Rim sign : On cholescintigraphy, increased uptake is seen in the region of the gallbladder fossa. Sign is specific for acute cholecystitis.


• Ring of fire sign : US finding. Hypervascular ring in the adnexa that may be seen with either ectopic pregnancy or corpus luteum.


• Ring sign : CT sign of epiploic appendagitis.


• Rosary sign : CT sign that may be seen with adenomyomatosis.


• Rugger jersey spine sign : Appearance of spine that may be seen with secondary hyperparathyroidism or chronic renal failure


• S sign of Golden : Right upper lobe atelectasis created by a central mass. Should raise the suspicion of a central neoplasm.


• Saber-sheath trachea : Appearance of trachea that may be seen with COPD.


• Saber shin : Appearance of tibia that may be seen with syphilis.


• Sandstorm appearance : Appearance of lungs that may be seen in pulmonary alveolar microlithiasis.


• Salt and pepper pattern : Flow voids seen in glomus tumors.


• Salt and pepper skull : Appearance of skull that may be seen in patients with hyperparathyroidism.


• Sandwich sign : Bulky lymphoma encasing mesenteric vessels.


• Sandwich vertebra : Sclerotic endplates that may be seen with osteopetrosis.


• Sausage digit : Soft tissue swelling of digits in patients with psoriatic arthritis.


• Scimitar sign : MRI appearance that may be seen with eccentric cystic adventitial disease.


• Scottie dog : On oblique radiographs, the posterior elements form the appearance of a Scottie dog. Spondylolysis can have the appearance of a collar around the neck.


• Shepard’s crook deformity : Appearance of proximal femur that may be seen with fibrous dyplasia.


• Shoulder sign : Appearance of hypertrophic pyloric stenosis that may be seen on upper GI series.


• Signet ring sign (Chest) : Sign of bronchiectasis.


• Signet ring sign (GU) : Sign of papillary necrosis on IVU.


• Small heart sign : Sign of tension pneumopericardium.


• Snowman : Appearance of heart that may be seen with supracardiac total anomalous pulmonary venous return.


• Snowstorm pattern (breast) : US pattern for breast implant rupture.


• Snowstorm pattern (Ob/gyn) : US pattern for a molar pregnancy.


• Soft-tissue rim sign : Appearance of a ureteral edema surrounding a calculus. Helps differentiates a calculus from a phlebolith (also see comet sign).


• Spade shape : Shape of tufts that may be seen with acromegaly.


• Spalding sign : Overlapping cranial sutures. Sign of fatal demise on prenatal ultrasound.


• Spider web : Appearnace of collateral vessels that may be seen on hepatic venography in Budd-Chiari syndrome.


• Spinnaker sail sign : Elevation of the thymus by air that may be seen with pneumomediastinum.


• Split pleura sign : CT sign of thoracic empyema.


• Spoke wheel enhancement pattern (GU) : May be seen with oncocytomas


• Spoke wheel enhancement pattern (GI) : May be seen with focal nodular hyperplasia.


• Spokewheel sign (GI) : Pattern of mesentery that may be seen with small bowel volvulus.


• Starry sky : US appearance that may be seen with hepatitis.


• Steeple sign : Appearance of narrowing of the subglottic tracheal lumen that may be seen with croup.


• Stepladder sign : US sign that may be seen in patients with intracapsular breast implant rupture.


• Straight line sign : PET sign of peritoneal carcinomatosis.


• Strawberry skull : Appearance of skull that may be seen on fetal US with Trisomy 18.


• String of beads : Appearnace of multiple stenosis that may be seen in patients with fibromuscular dysplasia.


• String sign : Appearance of hypertrophic pyloric stenosis that may be seen on upper GI series.


• Stripe sign : On a V/Q scan, subpleural activity in a region of decreased pulmonary perfusion. Sign is used to rule out pulmonary embolism.


• Subependymal Calcification : Tuberous Sclerosis


• Superior triangle sign : Sign that may be seen with right lower lobe atelectasis.


• Talar beak : Sign of talocalcaneal tarsal coalition.


• Tau sign : MRI sign of a persistent trigeminal artery.


• Telephone receiver shaped femora : Appearance of femora that can be seen with thanatophoric dysplasia.


• Terry Thomas sign : Sign of scapholunate ligament disruption (also see David Letterman sign).


• Throckmorton’s sign : The penis points to the pathology.


• Thumb sign : Classic lateral radiographic finding for epiglotitis.


• Thumbprinting : Sign of bowel wall thickening seen with entities such as ischemic bowel, diverticulitis, Crohn’s disease, and ulcerative colitis.


• Tip of the iceberg sign : Ultrasound sign that may be seen with mature cystic teratomas.


• Tit sign : Appearance of hypertrophic pyloric stenosis that may be seen on upper GI series.


• Tram-track sign (chest) : Sign of bronchiectasis.


• Tram line calcification (neuro) : Sign of optic nerve meningioma in tuberous sclerosis.


• Tram-track calcification (neuro) : Appearance of cortical calcifications that may be seen with Sturge Weber syndrome.


• Tram-track sign (nucs) : Bone scan finding that may be seen with hypertrophic osteoarthropathy.


• Tree in bud : Nonspecific pulmonary pattern seen on thin-section computed tomography,most commonaly with tuberculosis.


• Trident hand : Appearance of hands that may be seen with achondroplasia.


• Trough line sign : In posterior shoulder dislocation, frontal radiographs reveal two nearly parallel lines in the superomedial aspect of the humeral head.


• Umbrella sign : Sign of a ruptured globe.


• Wall-echo-shadow sign : Sign of cholelithiasis on US when the gallbladder is filled with calculi.


• Waterlily sign : Sign of hydatid cyst.


• Water can perineum : Sign of fistula formation secondary to periurethral abscess,associated with gonnorhea infection.


• Wave sign : Sign produced by lateral indentation of thymus by adjacent anterior ribs. This sign in seen in the pediatric population and represents a normal thymus.


• Whirlpool Sign : US sign of midgut volvulus in a neonate.


• Wimberger’s ring sign : A circular, opaque radiologic shadow surroundsing epiphyseal centers of ossification in patients with scurvy.


• Wimberger’s sign : Symmetrical lesions seen in the proximal tibial medial metaphysis in patient’s with syphilis.


• Westermark’s sign : Regional pulmonary oligemia secondary to pulmonary embolism.


• Yin-yang sign : Swirling blood flow pattern within a pseudoaneurysm.


• Yo-yo on a string sign : MRI appearance of a Stener lesion (see Gamekeeper thumb)