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.
16,868 results found
Article
Polyhydramnios
Polyhydramnios refers to a situation where the amniotic fluid volume is more than expected for gestational age.
It is generally defined as:
amniotic fluid index (AFI) >25 cm, though the cutoff in some centers is being reduced to 24 cm 14
largest fluid pocket depth (maximal vertical pocket) >8...
Article
Amniotic fluid index
The amniotic fluid index (AFI) is an estimate of the amniotic fluid volume in a pregnant uterus. It is part of the fetal biophysical profile.
Technique
the uterus is divided into four imaginary quadrants with the linea nigra and a mediolateral line running through the umbilicus acting as the ...
Article
Breast neoplasms
Breast neoplasms consist of a wide spectrum of pathologies from benign proliferations, high-risk lesions, precursor lesions, to invasive malignancies. This article provides an overview for radiologists, with a focus on breast cancer. For a summary article for medical students and non-radiologis...
Article
Spondylolisthesis
Spondylolisthesis (plural: spondylolistheses) denotes the slippage of one vertebra relative to the one below.
Terminology
Although etymologically, it is directionless (see below) and could be applied to both anterolisthesis and retrolisthesis, in practice, spondylolisthesis is used synonymous...
Article
Leave alone lesions - skeletal
Skeletal leave alone lesions, also called “do not touch” lesions, are so characteristic radiographically that further diagnostic tests such as a biopsy are unnecessary and can be frankly misleading and lead to additional unnecessary surgery. Thus a radiologic diagnosis should be made without a l...
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
Epidural spinal cord compression scale
The epidural spinal cord compression (ESCC) scale, sometimes known eponymously as the Bilsky scale, is used to assess the degree to which vertebral body metastasis compromises the spinal canal and whether cord compression is present. It may serve as a guide as to when intervention (radiotherapy ...
Article
Acquired cholesteatoma
Acquired cholesteatomas are far more common than congenital cholesteatomas and are almost always closely related to the tympanic membrane and pneumatized portion of the temporal bone from which most are thought to arise 9.
Cholesteatomas occur far more commonly in the middle ear than in the ext...
Article
Adrenal cortical carcinoma
An adrenal cortical carcinoma, also known as adrenocortical carcinoma, is a highly malignant but rare primary neoplasm of the adrenal gland. It may present as a hormonally active or inactive tumor.
Epidemiology
Although men and women are affected equally, functioning tumors are more common in...
Article
Thoracic duct embolization
Thoracic duct embolization (TDE) is a safe, efficacious treatment for chylothorax 1. Chylothoraces with a low drain output (<1L/day) are traditionally managed conservatively with dietary change, whilst high output (>1L/d) are managed with surgical thoracic duct (TD) ligation 2.
Thoracic duct em...
Article
Idiopathic pulmonary fibrosis
Idiopathic pulmonary fibrosis (IPF) is a clinical syndrome and considered the most common and the most lethal form of pulmonary fibrosis corresponding to the histologic and imaging pattern of usual interstitial pneumonia. It is more common in elderly men and diagnosed by:
histological or imagi...
Article
Ventriculoatrial shunt
Ventriculoatrial shunting is an alternative option for the diversion of CSF and relief of hydrocephalus. In this technique, the distal catheter is placed in the right atrium or even in the superior vena cava 1,2.
It is not the only alternative for the traditional ventriculoperitoneal shunt, an...
Article
Tornwaldt cyst
Tornwaldt cysts (also spelled as Thornwaldt cyst or Thornwald cyst) are common incidental benign midline nasopharyngeal mucosal cysts. A symptomatic cyst is also called Tornwaldt disease 7,8.
Epidemiology
Tornwaldt cysts are developmental and usually asymptomatic. In most cases they are found ...
Article
Wilbrand knee (optic radiation)
The Wilbrand knee refers to a small anterior loop of axons from the medial retina passing a short distance into the contralateral prechiasmatic optic nerve after decussating in the optic chiasm. It is said to account for the occurrence of the junctional scotoma caused by lesions at the junction ...
Article
Ligamentum teres of the hip
The ligamentum teres, also known as the ligamentum capitis femoris or round ligament of the hip, is an intra-articular ligament within the medial hip joint.
Gross anatomy
The ligament passes from the transverse ligament and acetabular notch of the acetabulum to the femoral head where it insert...
Article
Fetal cardiothoracic circumference ratio
Fetal cardiothoracic (C/T) circumference ratio is a parameter that can be used in the assessment of fetal cardiac and thoracic/chest wall anomalies. It is the ratio of the cardiac circumference to the thoracic circumference and may be easily measured on fetal ultrasound/echocardiography.
Radio...
Article
Limberg score
Limberg score is a semiquantitative color Doppler ultrasound assessment of the bowel wall vascularity in inflammatory bowel disease.
grade 0: normal bowel wall with no thickening (<4 mm), well-delineated mural stratification, no mural flow (no color Doppler signal)
grade 1: wall thickenin...
Article
Cardiac venous malformations
Cardiac venous malformations (also known as cardiac hemangiomas) consists of a slow flow venous malformation and is composed of numerous non-neoplastic endothelial-lined thin-walled channels with interspersed fat and fibrous septae.
Terminology
It is important to note that according to the ISS...
Article
CSF rhinorrhea
CSF rhinorrhea refers to a symptom of cerebrospinal fluid (CSF) leakage extracranially into the paranasal sinuses, thence into the nasal cavity, and exiting via the anterior nares. It can occur whenever there is an osseous and dural defect of the skull base that communicates directly or indirect...
Article
Sonographic values in obstetrics and gynecology
Obstetric and gynecological ultrasound is rampant with numerous cut-off values. Some of these get revised over the years. The following list is a useful aid to refer to and revise.
1 mm
rate of increase of a mean sac diameter per day in early pregnancy
2 mm
generally accepted value for a thi...