Articles
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More than 200 results
Article
Flip-flop renal enhancement
Flip-flop renal enhancement describes when an infarcted renal parenchyma alternates between hypoattenuation during the arterial phase, and hyperattenuation on the delayed phase of a contrast enhanced CT 1,2.
Terminology
Flip-flop renal enhancement should not be confused with the flip-flop eff...
Article
Bright rim sign (anterior talofibular ligament injury)
The bright rim sign in anterior talofibular ligament injury refers to a sign seen on MRI. A cortical defect with a bright dot-like or curvilinear high-signal-intensity, usually at the fibular attachment site, is seen on MRI. It has been described as an indicator of ATFL injury 1.
See also
brig...
Article
Bright spotty lesions (spinal cord)
Bright spotty lesions, also known as brighter spotty lesions, are a radiographic sign typically seen in, and very specific for, acute myelitis due to neuromyelitis optica spectrum disorder (NMOSD).
Bright spotty lesions are defined as intramedullary lesions of the spinal cord that are T2 hyperi...
Article
Mosaic attenuation pattern in lung
Mosaic attenuation is a descriptive term used in describing a patchwork of regions of differing pulmonary attenuation on CT imaging. It is a non-specific finding, although is associated with the following:
obstructive small airways disease: low attenuation regions are abnormal and reflect two p...
Article
J-shaped sella
A J-shaped sella is a variant morphology of the sella turcica, whereby the tuberculum sellae is flattened, thus forming the straight edge of the "J". The dorsum sellae remains rounded and forms the loop of the "J".
Differential diagnosis
Differential diagnosis for a J-shaped sella includes 1,2...
Article
Fleischner sign (enlarged pulmonary artery)
The Fleischner sign refers to a prominent central pulmonary artery that can be commonly caused either by pulmonary hypertension or by distension of the vessel by a large pulmonary embolus. It can be seen on chest radiographs, CT pulmonary angiography (CTPA), and MR pulmonary angiography (MRPA).
...
Article
Boas sign
Boas sign is a clinical sign that is defined as hyperesthesia felt by the patient to light touch in the right lower scapular region or the right upper quadrant of the abdomen. It is classically seen in patients with acute cholecystitis.
History and etymology
Ismar Isidor Boas (1858–1938), was ...
Article
Tent sign (breast)
The tent sign is a term referring to a characteristic appearance of the posterior edge of the breast parenchyma when a mass (usually an infiltrating lesion) causes its retraction and forms an inverted "V" that resembles the tip of a circus tent.
The detection of a "tent sign" is facilitated by ...
Article
Pseudosubarachnoid hemorrhage
Pseudosubarachnoid hemorrhage describes an apparent increased attenuation within the basal cisterns simulating true subarachnoid hemorrhage. It is usually due to cerebral edema.
Pathology
Etiology
The most common cause is cerebral edema where there is a decrease in parenchymal attenuation and...
Article
Enlarged hilar periportal space sign
The enlarged hilar periportal space sign refers to the widening of the periportal space seen on MRI in early liver cirrhosis.
Usage
Enlarged hilar periportal space sign is one of the early signs of cirrhosis and may be used to detect fibrotic changes in the liver in patients who do not yet hav...
Article
Sinus tarsi "see-through" sign
Sinus tarsi "see-through" sign is a radiological sign noted in pes cavus and/or hindfoot varus with the alignment of the sinus tarsi parallel to the x-ray beam resulting in the ability to "see-through" the sinus tarsi on lateral foot x-rays 1,2.
Article
Hepatic atrophy
Hepatic atrophy is a common appearance on imaging of the liver. It may result from obstruction of a major branch of the portal vein, bile ducts or hepatic veins. It does not usually occur secondary to hepatic arterial flow compromise. Compensatory hypertrophy of the unaffected segments/lobes is ...
Article
Air trapping
Air trapping or gas trapping is a pattern seen on expiratory CT and is caused by the relative retention of gas in lung distal to one or more obstructed airways 14. Expiration allows normal lung to deflate with consequent increased attenuation but air-trapping prevents deflation so that volume an...
Article
T sign (obstetrics)
The T sign is really the absence of a twin peak sign (or lambda (λ) sign) and is used in ultrasound assessment of a multifetal pregnancy.
It refers to the lack of chorion extending between the layers of the intertwin membrane, denoting a monochorionic pregnancy. The intertwin membrane comes to ...
Article
Sliver sign (patella)
The sliver sign refers to a curvilinear intra-articular osteochondral fragment in the knee joint on conventional knee radiographs. In the context of acute knee trauma and in association with joint effusion this sign is highly predictive of a recent transient lateral patellar dislocation 1.
Path...
Article
T sign (disambiguation)
The T sign has been described in several different pathologies:
T sign (obstetrics)
T sign (elbow MRI)
upper T sign (brain)
lower T sign (brain)
See also
tau sign
Article
Fluid bronchogram sign
The fluid bronchogram sign can be seen on chest CT or ultrasound as the presence of fluid attenuation material within respiratory bronchioles with surrounding collapsed or consolidated lung.
The presence of this sign suggests endobronchial obstruction as a precipitating cause for consolidation/...
Article
Terry-Thomas sign
The Terry-Thomas sign refers to an increase in the scapholunate space on an AP radiograph of the wrist (or coronal CT). The increased distance indicates scapholunate dissociation (often with rotary subluxation of the scaphoid) due to ligamentous injury. There is no consensus as to what measureme...
Article
V sign of interphalangeal joint dislocation
The V sign is characterized on a lateral radiograph of the digit by the separation of the dorsal base of the dislocated phalanx and the head of the phalanx proximal to the incongruent joint 1,2.
Before reduction, the V sign might be assessed to identify more subtle dorsal subluxations 1.
If th...
Article
Thumbprinting
Thumbprinting is a radiographic sign of large bowel wall thickening, usually caused by edema, related to an infective or inflammatory process (colitis). The normal haustra become thickened at regular intervals appearing like thumbprints projecting into the aerated lumen.
Pathology
Etiology
Th...
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