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
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
Valveless vein
The valveless veins are veins that lack venous valves. Most veins contain valves (known as the valvula venosa in the TA) to prevent backflow, i.e. ensuring that blood flow is always towards the heart 1.
It has been shown that veins that were previously thought to be valveless actually do have v...
Article
Tangent sign of supraspinatus muscle belly atrophy
The tangent sign is useful in helping to quantify supraspinatus muscle belly atrophy with a positive sign implicated with a poorer outcome after supraspinatus tendon tear repair.
Measurement
On a sagittal oblique plane, a line is drawn between the upper surface of the scapular spine and the up...
Article
Rectoanal intussusception
Rectoanal intussusception refers to the telescoping or infolding of the rectal wall within the rectum itself, or into the anal canal, or externally, during defecation.
Terminology
Rectoanal intussusception is also termed internal intussusception and internal procidentia1 .
Epidemiology
Recto...
Article
Interstitial lung abnormality
Interstitial lung abnormality (ILA) refers to incidental bilateral non-dependent CT patterns including reticulation, traction bronchiectasis and honeycombing that may be symptomatic, may progress to fibrosis and portend a higher all cause mortality risk 7.
Epidemiology
Although may vary from p...
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
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
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
Greater tubercle fracture of the shoulder
Greater tubercle/tuberosity fractures of the shoulder are a subtype of proximal humeral fractures.
Gross anatomy
The greater tubercle is the most lateral bony part of the shoulder. It is the site where three of the rotator cuffs insert to abduct or laterally rotate the shoulder joint (supraspi...
Article
Digital breast tomosynthesis
Digital breast tomosynthesis (DBT) is an imaging technique that allows a volumetric reconstruction of the whole breast from a finite number of low-dose two-dimensional projections obtained by different X-ray tube angles, with a geometric principle very similar to that applied in stratigraphic te...
Article
Koos grading scale
The Koos grading scale 1 is frequently used as a classification system for vestibular schwannomas.
Classification
grade 1: small intracanalicular tumor
grade 2: small tumor with protrusion into the cerebellopontine cistern (CPA); no contact with the brainstem
grade 3: tumor occupying the cer...
Article
Carotidynia
Carotidynia, also known as Fay syndrome, is a rare syndrome characterized by neck pain in the region of the carotid bifurcation.
It was classified by the International Headache Society (IHS) in 1988 as an idiopathic neck pain syndrome associated with tenderness over the carotid bifurcation with...
Article
Systemic hypertension
Systemic hypertension is defined medically as a blood pressure greater than 140/90 mmHg. The American College of Cardiology (ACC) and American Heart Association (AHA) have changed guidelines to indicate that pressures above 130/80 mmHg will be considered hypertension, however, the European Socie...
Article
Diffusion tensor imaging and fiber tractography
Diffusion tensor imaging (DTI) is an MRI technique that uses anisotropic diffusion to estimate the axonal (white matter) organization of the brain.
Fiber tractography (FT) is a 3D reconstruction technique to assess neural tracts using data collected by diffusion tensor imaging.
Diffusion-weigh...
Article
Intraductal papillary mucinous neoplasm
Intraductal papillary mucinous neoplasms or tumors (IPMNs or IMPTs) are epithelial pancreatic cystic tumors of mucin-producing cells that arise from the pancreatic ducts. They are most commonly seen in elderly patients.
On imaging, particularly MRCP, they are characterized by single or multipl...
Article
Transsphenoidal hypophysectomy
Transsphenoidal hypophysectomy is a commonly used surgical approach for pituitary region masses, with many significant advantages over open craniotomy.
History
The transsphenoidal approach was first described in 1907 by Schloffer, modified by Halstead and subsequently popularized by Harvey Cu...
Article
Skull vault hemangioma
Skull vault hemangiomas (SVH), or hemangiomas of the calvaria, are benign slow-growing vascular lesions affecting the skull diploe in any location. They have been renamed osseous venous (low-flow) vascular malformations given their nonneoplastic nature, but "hemangioma" remains commonly used.
P...
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
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...
Unable to process the form. Check for errors and try again.