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
Anal atresia
Anal atresia, or imperforate anus, refers to a spectrum of anorectal abnormalities ranging from a membranous separation to complete absence of the anus.
Epidemiology
The estimated incidence is 1 in 5000 live births.
Associations
There are frequent associations with other congenital abnormali...
Article
Flow-diverter stent
Flow-diverter stents are important devices in the management of intracranial aneurysms in both acute and elective settings, especially ones that are large, broad-necked, or fusiform.
Complications
Understanding the complication rates is important in obtaining informed consent from patients. In...
Article
Chemical shift artifact
Chemical shift artifact or misregistration is a type of MRI artifact. It is a common finding on some MRI sequences and used in magnetic resonance spectroscopy (MRS). This artifact occurs in the frequency-encoding direction and is due to spatial misregistration of fat and water molecules.
Chemi...
Article
Small bowel mesentery internal hernia
Small bowel mesentery internal hernias (alternative plural: herniae) are a form of internal bowel herniation involving protrusions of viscera through defects in the peritoneum or bowel mesentery.
Epidemiology
This type of internal herniation is more often seen in neonates than in adults ref.
...
Article
External auditory canal cholesteatoma
External auditory canal cholesteatomas are a rare subtype of acquired cholesteatoma.
Epidemiology
The external acoustic canal is a rare location for a cholesteatoma with an estimated incidence of around 1.2 per 1,000 new otological patients ref. The overall incidence rate in one large study wa...
Article
Tracheomalacia (differential)
A dilated trachea has numerous causes, and in almost all cases represents tracheomalacia (increased size and increased compliance).
As is almost always the case, various diameters have been used. Typical figures include >26 mm in men, >23 mm in women or >30 mm for both genders ref.
Although ma...
Article
Critical zone in rotator cuff tendons
The critical zone of the rotator cuff is an area approximately 8-15 mm from the insertion of the rotator cuff tendons onto the greater tubercle of the humeral head, mainly within the supraspinatus tendon. This is a watershed zone between the anterior and posterior circumflex humeral, thoracoacro...
Article
Ligamentum nuchae
The ligamentum nuchae or nuchal ligament is a large median ligament composed of tendons and fascia located between the posterior muscles of the neck.
Gross anatomy
The ligament nuchae covers the spines of C1 to C6 vertebrae. It is a superior and posterior extension of the supraspinous ligament...
Article
Rosette-forming glioneuronal tumors
Rosette-forming glioneuronal tumors (RGNTs) are rare, usually midline, tumors that involve the fourth ventricle and/or aqueduct of Sylvius.
Although relatively well-circumscribed on MRI and clinically indolent, they often invade surrounding tissues, involving the cerebellum, pons and even the ...
Article
Reye syndrome
Reye syndrome is a rare pediatric condition characterized by acute onset encephalopathy, severe vomiting and fatty liver failure. It typically presents in children recovering from a viral illness, most commonly influenza or chickenpox 1.
Epidemiology
Reye syndrome is usually seen between the ...
Article
Myocardium
The myocardium defines the middle layer of the cardiac wall between the endocardium and the pericardium and forms the muscular part of the heart.
Gross anatomy
The myocardium represents the middle layer of the cardiac wall. It is located between the endocardium and the epicardial layer of the ...
Article
Essex-Lopresti fracture-dislocation
Essex-Lopresti fracture-dislocation is characterized by a fracture of the radial head, dislocation of the distal radioulnar joint and rupture of the antebrachial interosseous membrane 3.
Epidemiology
As little as 20% of Essex-Lopresti fracture-dislocations are recognized at the time of initial...
Article
Crohn disease
Crohn disease, also known as regional enteritis, is an idiopathic inflammatory bowel disease characterized by widespread discontinuous gastrointestinal tract inflammation. The terminal ileum and proximal colon are most often affected. Extraintestinal disease is common.
Epidemiology
The diagnos...
Article
Ascites
Ascites (hydroperitoneum is a rare synonym) is defined as an abnormal amount of intraperitoneal fluid.
Terminology
Ascites (plural is the same word) tends to be reserved for relatively sizable amounts of peritoneal fluid. The amount has not been defined formally. It is noted physiologically, h...
Article
Decompressive craniectomy
Decompressive craniectomies are craniectomies performed to relieve raised intracranial pressure, most commonly in the setting of florid cerebral edema following cranial trauma or swelling following infarction 1.
History
Craniectomies for the treatment of cranial trauma date back to at least 10...
Article
Computer aided diagnosis
Computer aided diagnosis (CAD) is the use of a computer generated output as an assisting tool for a clinician to make a diagnosis. It is different from automated computer diagnosis, in which the end diagnosis is based on a computer algorithm only.
As an early form of artificial intelligence, co...
Article
Artificial intelligence
Artificial intelligence (AI) has been defined by some as the "branch of computer science dealing with the simulation of intelligent behavior in computers" 1, however, the precise definition is a matter of debate among experts.
An alternative definition is the branch of computer science dedicat...
Article
Cytotoxic lesions of the corpus callosum (CLOCCs)
Cytotoxic lesions of the corpus callosum (CLOCCs) represent a collection of disparate conditions that can cause signal change in the corpus callosum, usually involving the splenium.
Terminology
The term cytotoxic lesions of the corpus callosum (CLOCCs) has been proposed 12 as a more precise d...
Article
Inflammatory leiomyosarcoma
Inflammatory leiomyosarcomas are malignant tumors with smooth muscle differentiation and a prominent inflammatory infiltrate that were recognized as a distinct entity by the WHO in 2020 1-3.
Epidemiology
Inflammatory leiomyosarcomas are very rare lesions with most cases seen in adults with a p...
Article
Hemiplegic migraine
Hemiplegic migraines are an uncommon type of migraine with aura wherein patients present with usually reversible motor weakness, typically unilateral. They can be challenging to distinguish from seizure with Todd paresis or ischemic stroke, even with the benefit of MRI 1.
Epidemiology
Compared...