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.

More than 200 results
Article

Parastomal hernia

Parastomal hernias (alternative plural: herniae) are defined as the protrusion of abdominal contents through an abdominal wall defect in the vicinity of the stoma. Classification The hernia may contain a loop of bowel forming the stoma itself, omentum, and/or intestinal loops other than that f...
Article

MitraClip device

A MitraClip is a device for percutaneous mitral valve repair. It is a percutaneous edge-to-edge attachment system that mimics the surgical procedure. This technique creates a tissue bridge between the anterior and posterior leaflets, employing one clip deployed through transseptal catheterizatio...
Article

Benign and malignant characteristics of breast lesions at ultrasound

Benign and malignant characteristics of breast lesions at ultrasound allow the classification as either malignant, intermediate or benign based on work published by Stavros et al. in 1995. Radiographic features Ultrasound Malignant characteristics (with positive predictive values) sonographi...
Article

Accessory left atrial appendage

An accessory left atrial appendage is a frequent fortuitous finding in cardiac imaging, encountered in ~10% of patients. They are more often seen as a small diverticular structure projecting from the right upper side of the left atrial wall. Differential diagnosis it must not be confused with ...
Article

Ischemic colitis

Ischemic colitis refers to inflammation of the colon secondary to vascular insufficiency and ischemia. It is sometimes considered under the same spectrum as intestinal ischemia. The severity and consequences of the disease are highly variable. Epidemiology Ischemic bowel is typically a disease...
Article

Miliary lung nodules (mnemonic)

The list of differential diagnoses for miliary lung nodules can be recalled with the mnemonic: TEMPEST Mnemonic TEMPEST T: tuberculosis E: eosinophilic granuloma M: metastases (especially thyroid) P: pneumoconiosis E: extrinsic allergic alveolitis (now known as hypersensitivity pneumonit...
Article

Cervical rib

Cervical ribs are supernumerary or accessory ribs arising from the seventh cervical vertebra. They occur in ~0.5% of the population, are usually bilateral, but often asymmetric 2, and are more common in females. Related pathology Although cervical ribs are usually asymptomatic, they are the mo...
Article

Ductus deferens

The ductus deferens (plural: ductus deferentes), formerly known as the vas deferens (plural: vasa deferentia), forms part of the male internal genitalia where it transports sperm from the epididymis to the ejaculatory duct. Terminology In modern anatomic nomenclature, it is no longer referred ...
Article

Multinodular goiter

Multinodular goiter (MNG) is defined as an enlarged thyroid gland (i.e. goiter) due to multiple nodules which may have normal, decreased or increased function.  Terminology When increased activity and hyperthyroidism are present then the condition is referred to as a toxic multinodular goiter ...
Article

Lung cancer (staging - IASLC 7th edition) (historical)

The IASLC (International Association for the Study of Lung Cancer) 7th edition lung cancer staging system was proposed in 2010 and has now been updated and superseded by the 8th edition, published in 2016. Small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC) used to be staged di...
Article

Brainstem glioma

Brainstem gliomas are primary tumors most frequently involving the pons and are typically diagnosed in children. Terminology Brainstem glioma is not a formal diagnosis but rather a catch-all term encompassing a heterogeneous group that varies greatly in histology and prognosis. It was useful, ...
Article

Primary cutaneous melanoma

Primary cutaneous melanoma is the most common subtype of melanoma, a malignant neoplasm that arises from melanocytes. Melanocytes predominantly occur in the basal layer of the epidermis but do occur elsewhere in the body. Primary cutaneous melanoma is by far the most common type of primary melan...
Article

Azygos vein

The azygos vein is a unilateral vessel that ascends in the thorax to the right of the vertebral column, carrying deoxygenated blood from the posterior chest and abdominal walls. It forms part of the azygos venous system. Terminology The spelling azygous when referring to the vein is incorrect,...
Article

Epipericardial fat necrosis

Epipericardial fat necrosis (also sometimes purely categorized as pericardial fat necrosis or epicardial fat necrosis) is a rare self-limiting cause of acute pleuritic pain in an otherwise healthy individual, without fever or cough. It occurs external to the pericardium. Clinical presentation ...
Article

Stove-in chest

A stove-in chest is a rare and complex type of flail chest injury where the flail segment collapses into the chest. It is usually due to severe blunt trauma to the chest wall and is rarely encountered in imaging or emergency medicine due to the high mortality at the scene. It may evolve over day...
Article

Peripartum/postpartum cardiomyopathy

Peripartum/postpartum cardiomyopathy is a dilated cardiomyopathy that may occur in the last trimester of pregnancy through the first several months postpartum. Epidemiology The estimated incidence in the United States ranges from one in 900 to one in 4000 live births, with an increased inciden...
Article

Hair artifact

Hair artifact and hair-product artifacts are artifacts produced by the presence of the patient's hair, hair accessories (e.g. hair clip) and hair products (e.g. shampoo) within the field of view during acquisition of an image, which can affect all modalities to varying degrees. For example, in m...
Article

Excretory phase

The excretory phase also known as the urographic phase is a postcontrast injection time range in which there is an optimal enhancement of the renal collecting systems. Technique The acquisition time depends on the intravenous device (central or peripheral), the concentration of the contrast me...
Article

Loss of the insular ribbon sign

The loss of the insular ribbon sign refers to a loss of definition of the gray-white interface in the lateral margin of the insular cortex ("insular ribbon") and is considered an early (hyperacute to acute) CT sign of MCA territory infarction. The insular cortex is more susceptible to ischemia ...
Article

Ring of fire sign (adnexa)

The ring of fire sign, also known as ring of vascularity, signifies a hypervascular lesion with peripheral vascularity on color or pulsed Doppler examination of the adnexa due to low impedance high diastolic flow 1. This sign can be seen in: corpus luteum cyst (more commonly) ectopic pregnancy

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.