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
Cardiac CT
Computed tomography of the heart or cardiac CT is routinely performed to gain knowledge about cardiac or coronary anatomy, to detect or diagnose coronary artery disease (CAD), to evaluate patency of coronary artery bypass grafts or implanted coronary stents or to evaluate volumetry and cardiac f...
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
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
Pulmonary artery catheter
Pulmonary artery catheters (PAC or Swan-Ganz catheters) are balloon flotation catheters that are inserted into the pulmonary arteries. They can be inserted simply, quickly, with little training and without fluoroscopic guidance at the bedside, even in the seriously ill patient.
Usage
Historica...
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
Spinning top urethra
Spinning top urethra is non-obstructive posterior urethral dilatation seen on voiding cystourethrography, mainly in females. It was initially considered as an indicator of distal urethral narrowing/stenosis. However, it is now believed to be due to functional discoordinate voiding or bladder ins...
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
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
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
Modic type endplate changes
Modic type endplate changes represent a classification for vertebral body endplate MRI signal changes, first described in 1988 1. It is widely recognized by radiologists and clinicians and is a useful shorthand for reporting MRIs of the spine.
Modic type 1 has received renewed attention due to ...
Article
Benign enhancing foramen magnum lesion
Benign enhancing foramen magnum lesions, also described as high signal lesions, have been anecdotally seen by radiologists for years but only described as an incidental finding on 3D FLAIR MRI in a typical location in the foramen magnum just posterior to the intradural vertebral artery.
Epidem...
Article
Myocardial infarction
Myocardial infarction (MI), colloquially known as a heart attack, an acute coronary syndrome, results from interruption of myocardial blood flow and resultant ischemia and is a leading cause of death worldwide.
Epidemiology
Risk factors
male > females
age
>45 years for males
>55 years for...
Article
MR tagging
Cardiac MR tagging or myocardial tagging refers to an MRI-based acquisition method designed for the analysis of myocardial deformation.
Methodology
The method exploits tissue magnetization as a tissue property. A local magnetic saturation grid of dark-lined tissue markers known as tags are ind...
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
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...