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
Tension pneumocephalus
Tension pneumocephalus is a neurosurgical emergency that occurs when subdural air causes a mass effect over the underlying brain parenchyma, often from a ball-valve mechanism causing one-way entry of air into the subdural space 1.
Clinical presentation
Tension pneumocephalus has a varied clini...
Article
All-trans-retinoic acid syndrome
All-trans-retinoic acid (ATRA) syndrome, is the more common cause of differentiation syndrome 8. Acute promyelocytic leukemia (APL) cells respond to therapeutic levels of this normal plasma derivative of vitamin A by maturating into normal granulocytes which can cause capillary leakage and organ...
Article
Snowstorm sign (extracapsular breast implant rupture)
The snowstorm sign on breast ultrasound imaging represents the presence of free silicone droplets mixed with breast parenchymal tissue causing characteristic homogeneously hyperechoic, dense shadowing, with dispersion of the ultrasound beam. It is considered the most reliable sign of extracapsul...
Article
Alpha angle (cam morphology)
The alpha angle is a radiological measurement proposed for the detection of cam morphology, which is sometimes associated with femoroacetabular impingement (FAI).
Terminology
The term alpha angle is also used in a separate and unrelated context in the evaluation of developmental dysplasia of ...
Article
Intestinal transplant
Intestinal transplantation is a surgical treatment for intestinal failure. It is one of the most rarely performed transplant procedures performed, exclusively involving the transplantation of donor small bowel to a recipient, with an ileostomy formation.
Due to the high risk of complications w...
Article
Intracerebral hemorrhage
An intracerebral hemorrhage, or intraparenchymal cerebral hemorrhage, is a subset of an intracranial hemorrhage as well as of stroke, defined by the acute accumulation of blood within the brain parenchyma.
This article concerns non-traumatic intracerebral hemorrhages; traumatic hemorrhagic cere...
Article
Minimal aortic injury
Minimal aortic injury (MAI) is a mild form of blunt traumatic aortic injury which are limited to the aortic intima and are recognized more frequently due to the use of high-resolution vascular imaging in trauma.
Epidemiology
Minimal aortic injuries account for 10-28% of all blunt traumatic aor...
Article
Rule of Spence
The Rule of Spence is a radiologic method to evaluate the likelihood of injury to the transverse atlantal ligament (TAL) on an open mouth AP (“peg”) radiograph. As originally framed, if the combined projection of the lateral masses of the atlas is more than 6.9 mm beyond the lateral masses of th...
Article
Rockwood classification of acromioclavicular joint injury
The Rockwood classification (1998) is the most commonly used (c.2024) classification system in use for acromioclavicular joint injuries 3,8,9.
Usage
This well-known 6-type system is a modification of the earlier 3-class classification system described by Allman (1967) 2 and Tossy (1963). The ...
Article
Migraine
Migraines are a common primary headache disorder and can present variably. Typically they consist of debilitating headaches, accompanied by an aura in one-third of patients.
Epidemiology
Migraine is a very common condition, with a 1-year prevalence of 12% 8. It is most prevalent in early-middl...
Article
Brachial plexus injuries
Brachial plexus injuries are a spectrum of upper limb neurological deficits secondary to partial or complete injury to the brachial plexus, which provides the nerve supply of upper limb muscles.
Clinical presentation
Trauma, usually by motor vehicle accidents, involves severe traction on the ...
Article
Subacromial impingement
Subacromial impingement is the most common form of shoulder impingement and occurs secondary to attrition between the coracoacromial arch and the underlying supraspinatus tendon or subacromial bursa, leading to tendinopathy and bursitis respectively.
Pathology
Etiology
acromial shape
os acro...
Article
Syndesmotic screw fixation
Syndesmotic screw fixation is a rigid fixation technique for stabilization of distal tibiofibular syndesmosis injury. Depending on the injury and the surgeon's preference it can involve the placement of one or two syndesmotic screws and can be combined with an antiglide plate.
Indications
Indi...
Article
Radial scar
Radial scar, or complex sclerosing lesion, is a rosette-like proliferative breast lesion. It is not related to surgical scarring. Some authors, however, reserve the latter term to lesions over 1 cm 5.
It is an idiopathic process with sclerosing ductal hyperplasia.
Its significance is that it...
Article
Prostatic leiomyoma
Prostatic leiomyomas are benign mesenchymal tumors of the prostate.
Epidemiology
Prostatic leiomyomas are very rare 1-3.
Diagnosis
The diagnosis of prostatic leiomyoma is based on histology.
Clinical presentation
Prostatic leiomyomas can present with voiding difficulties or obstructive sym...
Article
Lipomatous hypertrophy of the interatrial septum
Lipomatous hypertrophy of the interatrial septum is a relatively uncommon disorder of the heart characterized by benign fatty infiltration of the interatrial septum. It is commonly found in elderly and obese patients as an asymptomatic incidentally discovered finding.
Epidemiology
The prevale...
Article
Uteroplacental blood flow assessment
Uteroplacental blood flow assessment is an important part of fetal well-being assessment and evaluates Doppler flow in the uterine arteries and rarely the ovarian arteries.
Pathology
In a non-gravid state and at the very start of pregnancy the flow in the uterine artery is of high pulsatility ...
Article
Elevated prolactin (differential)
Elevated prolactin can be due to a number of causes, including elevated production/secretion as well as reduced inhibition.
Prolactin is controlled by numerous homeostatic mechanisms, with tonic secretion of prolactin inhibitory hormone (dopamine) by the hypothalamus having a dominant effect 1...
Article
Benign post-traumatic pseudopneumoperitoneum
Benign post-traumatic pseudopneumoperitoneum is the presence of ectopic gas typically between the 5th-10th intercostal spaces after high-energy trauma in the absence of other causes of pseudopneumoperitoneum such as pneumomediastinum 9.
Epidemiology
Occurs with an incidence of 5% post-trauma...
Article
Peroxisome biogenesis disorder
Peroxisome biogenesis disorders (PBDs) are autosomal recessive, inborn errors of peroxisomes, a eukaryotic cell organelle critical to the breakdown of very long chain fatty acids via beta-oxidation.
Terminology
The terminology has changed to "severe", "intermediate", and "mild" forms of Zellw...