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.

16,888 results found
Article

Colon polyp

Colon polyps are mucosal outgrowths of the colon wall. They are of interest to physicians and radiologists because of the accepted progression of adenomatous polyps to colon carcinoma. Pathology adenomatous colon polyps tubular polyp tubulovillous polyp villous colon polyp dysplastic colon...
Article

X-ray quantity and quality

X-ray spectrum quantity refers to the number of photons within the primary X-ray beam and is measured by mAs (milliampere-seconds) 2. Meanwhile, the intensity of the beam is defined as rate of flow of energy per unit area perpendicular to the beam 3, also known as energy fluence rate, with units...
Article

References

References are essential to the pursuit of the high academic standards of Radiopaedia.  Any recommendations for patient care must be based on science, evidence, and clinical reasoning while avoiding advocating for or promoting, practices that are not, or not yet, adequately based on science, ev...
Article

Medical abbreviations and acronyms (C)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter C and may be encountered in medicine and radiology (please keep both the main list and any sublists in alphabetic order). A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q...
Article

Status epilepticus

Status epilepticus is an acute and prolonged seizure that persists for a sufficient length of time or is repeated frequently enough that recovery between attacks does not occur. It is a clinical emergency associated with high morbidity and mortality. Terminology Status epilepticus is a broad t...
Article

Medical abbreviations and acronyms (N)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter N and may be encountered in medicine and radiology (please keep the main list and any sublists in alphabetic order). A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R ...
Article

Medical abbreviations and acronyms (E)

This article contains a list of commonly used medical abbreviations and acronyms that start with the letter E and may be encountered in medicine and radiology (please keep both the main list and any sublists in alphabetic order). A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q...
Article

Duodenum

The duodenum (plural: duodena or duodenums) is the first part of the small intestine and is the continuation of the stomach. Gross anatomy The duodenum is a 20-30 cm C-shaped hollow viscus predominantly on the right side of the vertebral column. It lies at the level of L1-3 and the convexity o...
Article

Brain metastases

Brain metastases are estimated to account for approximately 25-50% of intracranial tumors in hospitalized patients. Due to great variation in imaging appearances, these metastases present a common diagnostic challenge that can importantly affect the management approach for individual patients. ...
Article

MRI contrast agent safety

Though considered safer than the frequently used iodinated contrast agents used in x-ray and CT studies, there are safety issues with MRI contrast agents as well. Paramagnetic metal ions suitable as MRI contrast agents are all potentially toxic when injected IV at or near doses needed for clinic...
Article

Photon-counting computed tomography

Photon-counting computed tomography (PCCT) is a technology in CT that could represent the next major technological milestone in the field. Briefly, photon-counting CT uses energy-resolving detectors, thereby enabling scanning at multiple energies. Technique Physical principles Clinical CT sys...
Article

Glossopharyngeal nerve

The glossopharyngeal nerve is the ninth cranial nerve (CN IX). It exits the brainstem out from the sides of the upper medulla, just rostral to the vagus nerve and has sensory, motor, and autonomic components (TA: nervus glossopharyngeus or nervus cranialis IX). Gross anatomy Origin There are ...
Article

iRefer guidelines

The publication iRefer Guidelines: Making the best use of clinical radiology is now in its eighth edition 1. It is published by The Royal College of Radiologists (RCR) in the UK. iRefer comprises a comprehensive set of evidence-based guidelines to help doctors and other health professionals deci...
Article

Progressive supranuclear palsy

Progressive supranuclear palsy (PSP), also known as the Steele-Richardson-Olszewski syndrome, comprises a group of related tauopathies and is considered a neurodegenerative disease with no efficacious treatment.  Epidemiology Progressive supranuclear palsy typically becomes clinically apparent...
Article

American College of Radiology

The American College of Radiology (ACR) was founded in 1923 by Albert Soiland, an American radiologist 2. Its contemporary core purpose, according to its website, is "To serve patients and society by empowering members to advance the practice, science and professions of radiological care" 1. Hi...
Article

Mechanical index

The mechanical index (MI) is an attempt to measure part of an ultrasound beam's bioeffects. The mechanical index is found on most ultrasound display screens, along with the thermal index. Mechanical index is an indication of an ultrasound beam's ability to cause cavitation-related bioeffects, a...
Article

RANZCR pathology examination

The RANZCR pathology examination is part of the RANZCR Phase 2 written examinations. It aims to assess both core and advanced knowledge of pathology, and its application to radiological practice. The examination can be attempted as early as 12 months from the start of training if all the other ...
Article

Sarcomatoid renal cell carcinoma

Sarcomatoid renal cell carcinomas (sRCC) may develop when one of the more common histologic subtypes of renal cell carcinoma degenerates into a sarcoma. On imaging, they are generally large masses, with irregular contours, and malignant-appearing, but do not have specific imaging features. Epi...
Article

Magerl classification of thoracolumbar spinal fractures (historical)

The Magerl classification, one of many thoracolumbar spinal fracture classification systems, was adopted as the original AO classification in 1994 but has since then been superseded: see the AO Spine classification of thoracolumbar injuries. Usage Although the Magerl classification is based on...
Article

Prolonged heterogeneous liver enhancement (CEUS)

Prolonged heterogeneous liver enhancement (PHLE), also informally termed as the "disappearing liver" phenomenon, is a very rare, benign complication of ultrasound contrast media, of unknown etiology 1. PHLE manifests itself as confluent, rapidly appearing hyperechoic foci in the liver, that may ...

Updating… Please wait.

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

 Thank you for updating your details.