Articles
Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
16,873 results found
Article
Idiopathic interstitial pneumonias
The idiopathic interstitial pneumonias (IIPs) are diffuse interstitial lung diseases of unknown cause. They are characterized by cellular infiltration of the interstitial compartment of the lung with varying degrees of inflammation and fibrosis.
Classification
Over the years many attempts have...
Article
Clustering
Clustering, also known as cluster analysis, is a machine learning technique designed to group similar data points together. Since the data points do not necessarily have to be labeled, clustering is an example of unsupervised learning. Clustering in machine learning should not be confused with d...
Article
Empyema vs pleural effusion
An empyema can resemble a pleural effusion and can mimic a peripheral pulmonary abscess. Features that help distinguish a pleural effusion from an empyema include:
Shape and location
Empyemas usually:
form an obtuse angle with the chest wall
unilateral or markedly asymmetric whereas pleural ...
Article
Arterial transit artifact
The arterial transit artifact, sometimes known as the bright vessel appearance or trapped labeled spins, on noncontrast arterial spin labeling (ASL) MR perfusion of the brain refers to curvilinear high signal corresponding to labeled blood within cerebral arteries. Normally, in ASL imaging, labe...
Article
Extrapontine myelinolysis
Extrapontine myelinolysis (EPM) is one of the complications occurring secondary to rapid correction of hyponatremia, and is, along with central pontine myelinolysis encompassed by the term osmotic demyelination syndrome.
In the vast majority of cases, it is associated with central pontine myeli...
Article
Peritoneal hydatidosis
Peritoneal hydatidosis occurs secondary to the seeding of echinococcosis into the peritoneum, usually secondary to the rupture of hydatid disease of the liver.
Pathology
Seeding involves the entire peritoneum and gives appearance of a multiloculated mass.
Classification
Peritoneal hydatidos...
Article
Greenstick fracture
Greenstick fractures are incomplete fractures of long bones and are usually seen in young children, more commonly less than 10 years of age. They are commonly mid-diaphyseal, affecting the forearm and lower leg. They are distinct from torus fractures.
Pathology
Mechanism
Greenstick fractures ...
Article
Metacarpal fracture
Metacarpal fractures are common accounting for 10% of all fractures and 40% of all hand fractures. The most common metacarpal fracture is fracture of the neck of the fifth metacarpal, or boxer's fracture, accounting for 10% of all hand fractures.4
Terminology
Specific names are given to fractu...
Article
Hip joint injection (technique)
Hip joint injections can be performed with a variety of image guidance, including fluoroscopy and ultrasound, which are used to administer MRI arthrogram injectate, or a steroid containing anesthetic arthrogram injectate.
Indications
MRI: labral injury
anesthetic
pain/arthropathy, e.g. ost...
Article
Positive ulnar variance
Positive ulnar variance describes where the distal articular surface of the ulna is more than 2.5 mm distal to the articular surface of the radius.
It plays important role in wrist pathology such as ulnar impaction syndromes and thinning of the triangular fibrocartilage complex.
Radiographic ...
Article
Testicular cancer
Testicular cancers are the most common malignancy in men between the ages of 20 and 34 years.
Epidemiology
Testicular cancer is uncommon, accounting for less than 1% of all internal organ malignancies 2.
The commonest histology of the tumor varies with the age of affected individuals. Over 90...
Article
Inferior vena caval thrombosis
Inferior vena caval thrombosis is an essential diagnosis while evaluating any neoplastic lesion, or portal hypertension. It is also important to differentiate bland thrombus from tumor thrombus.
Clinical features
A patient can present with many features which include
bilateral pedal edema
Bu...
Article
Gadolinium contrast agents
Gadolinium-based contrast media (GBCM), gadolinium-based contrast agents (GBCAs), or simply gadolinium contrast agents, are molecular complexes containing the rare earth metal gadolinium, chelated to a carrier ligand. They are a type of paramagnetic contrast agent, which are the primary class of...
Article
Asymmetry of the lateral ventricles
The lateral ventricles occasionally show small side to side differences in size on CT or MRI of the brain. This asymmetry of the lateral ventricles (ALV) is an anatomic variant in most cases.
Epidemiology
The prevalence of asymmetry in lateral ventricle size in those without evidence of underl...
Article
Thoracic actinomycosis infection
Thoracic actinomycosis refers to an uncommon indolent infection caused principally by the genus Actinomyces (higher prokaryotic bacteria belonging to the family Actinomyceataceae).
Epidemiology
While it is rare in general, the thoracic form actinomycosis constitutes ∼15% of the total burden of...
Article
Facial fractures
Facial fractures are commonly caused by blunt or penetrating trauma at moderate or high levels of force. Such injuries may be sustained during a fall, physical assault, motor vehicle collision, or gunshot wound. The facial bones are thin and relatively fragile, making them susceptible to injury....
Article
Pneumatosis coli
Pneumatosis coli is a descriptive sign presenting radiographically as intramural gas limited to the colonic wall.
Terminology
There are different terminologies in the medical literature, such as pneumatosis intestinalis, pneumatosis coli, and pneumatosis cystoides intestinalis. Pneumatosis in...
Article
Duchenne muscular dystrophy
Duchenne muscular dystrophy (DMD) is a dystrophinopathy and the most common muscular dystrophy.
Epidemiology
Duchenne muscular dystrophy has an incidence of 1 in 3500 to 5000 males 1,2. The condition is extremely rare in females due to its inheritance pattern, as discussed below 1.
Clinical p...
Article
Radiology (journal)
Radiology is a peer-reviewed monthly journal published by the Radiological Society of North America (RSNA) and its first edition was issued in September 1923 1.
Its current editor is David A Bluemke. It was recently announced that Linda Moy, an American breast radiologist, had been appointed as...
Article
Tibiotalar angle
The tibiotalar angle is between the anatomic axis of the tibia and the superior articular surface of the talar dome. Differently from the talar tilt, the tibiotalar angle uses the tibial longitudinal axis instead of the distal articular surface as a tibial reference point.
Usage
The tibiotalar...
Unable to process the form. Check for errors and try again.