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.
1,463 results found
Article
3-6-9 rule (bowel)
The 3-6-9 rule is a simple aide-memoire describing the normal bowel caliber:
small bowel: <3 cm
large bowel: <6 cm
appendix: <6 mm
cecum: <9 cm
Above these dimensions, the bowel is generally considered dilated, and obstruction or an adynamic/paralytic ileus should be considered.
Article
4D syndrome
4D syndrome is a term used to describe a manifestation of syndromic glucagonoma, a type of pancreatic endocrine tumor.
D: dermatitis 2
necrolytic migratory erythema - a widespread rash, tending to involve perioral and perigenital regions
oral rashes (angular stomatitis, cheilitis)
tend to re...
Article
Aaron sign
Aaron sign is a clinical sign that is defined as a feeling of distress and pain in the epigastric, umbilical and praecordial regions, on steady pressure over McBurney point, it is suggestive of chronic appendicitis.
History and etymology
Charles Dettie Aaron (1866–1951) was an American gastroe...
Article
AAST injury scoring scales
The American Association for the Surgery of Trauma (AAST) injury scoring scales are the most widely accepted and used system of classifying and categorizing traumatic injuries. Injury grade reflects severity, guides management, and aids in prognosis. 32 different injury scores are available (c. ...
Article
AAST spleen injury scale
The American Association for the Surgery of Trauma (AAST) splenic injury scale, most recently revised in 2018, is currently the most widely used grading system for splenic trauma.
The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criter...
Article
Abdomen (AP supine view)
The AP supine abdominal radiograph can be performed as a standalone projection or as part of an acute abdominal series, depending on the clinical question posed, local protocol and the availability of other imaging modalities.
Indications
This view is useful in assessing abdominal pathologies,...
Article
Abdomen (dorsal decubitus view)
The dorsal decubitus view is a supplementary projection often replacing the lateral decubitus view in the context of an unstable patient who is unable to roll nor stand. Used to identify free intraperitoneal gas (pneumoperitoneum). It can be performed when the patient is unable to be transferred...
Article
Abdomen (lateral decubitus view)
The lateral decubitus abdominal radiograph is used to identify free intraperitoneal gas (pneumoperitoneum). It can be performed when the patient is unable to be transferred to, or other imaging modalities (e.g. CT) are not available. The most useful position for detecting free intraperitoneal ai...
Article
Abdomen (oblique view)
AP oblique supine radiograph is a projection often used in barium studies and foreign body localization.
Indications
This view is normally performed when localizing foreign bodies or lines within the abdominal cavity. Additionally, the oblique abdominal series can be utilized in the assessment...
Article
Abdomen (PA erect view)
The PA erect abdominal radiograph is often obtained in conjunction with the AP supine abdominal view in the acute abdominal series of radiographs.
The erect abdominal radiograph has virtually disappeared from clinical practice in the United Kingdom, with studies dating back to the 1980s affirmi...
Article
Abdomen (PA prone view)
The PA prone radiograph is rarely performed and is often utilized when a patient is unable to lay supine. The projection is adequate for the examination of the abdominal cavity, however, not as practical for the renal structures due to magnification.
Indications
This view is useful in visualiz...
Article
Abdomen radiograph (pediatric)
The abdomen radiograph is a commonly requested examination in the pediatric patient. Children that present for abdominal x-rays are often very unwell, therefore specialized techniques and appropriate communication are essential for gaining the child's cooperation.
Indications
Performing abdom...
Article
Abdominal adhesions
Abdominal adhesions are bands of scar tissue (fibrous or fibrofatty), most often occurring as a complication of previous abdominal surgery.
Pathology
Adhesions often occur with
multiple abdominal operations or previous postoperative intra-abdominal complications
history of intra-abdominal infla...
Article
Abdominal and pelvic anatomy
Abdominal and pelvic anatomy encompasses the anatomy of all structures of the abdominal and pelvic cavities.
This anatomy section promotes the use of the Terminologia Anatomica, the international standard of anatomical nomenclature.
Article
Abdominal cavity
The abdominal cavity is divided into two major compartments, the peritoneum and retroperitoneum, early in fetal development.
The parietal peritoneum is reflected over the peritoneal organs, forming supporting peritoneal ligaments, mesenteries, and omenta.
The peritoneal reflections carry vess...
Article
Abdominal compartment syndrome
Abdominal compartment syndrome is a disease defined by the presence of new end-organ dysfunction secondary to elevated intra-abdominal pressure. Radiological diagnosis is difficult and usually suggested when a collection of imaging findings are present in the appropriate clinical setting or if t...
Article
Abdominal distension (mnemonic)
A mnemonic for causes of abdominal distension (6 Fs) is:
F: fat
F: fluid
F: flatus
F: feces
F: fetus
F: fulminant mass
Article
Abdominal hernia
Abdominal hernias/herniae may be congenital or acquired and come with varying eponyms. They are distinguished primarily based on type, location and content.
Epidemiology
75-80% of all hernias are inguinal ref.
Pathology
Content of the hernia is variable, and may include:
small bowel loops
...
Article
Abdominal (lateral view)
The lateral view abdominal radiograph is a less common projection of the abdomen, it is different from the lateral decubitus view of the abdomen and looks more like a lateral lumbar spine view.
Indications
This projection is often requested as a useful problem-solving view that can complement ...
Article
Abdominal migraine
Abdominal migraine is a syndrome that presents as recurrent episodes of severe paroxysmal abdominal pain, coupled with vasomotor symptoms, nausea, and emesis that lasts for at least 1 hour 3. Historically it has tended to be a pediatric diagnosis, but it is now increasingly seen in adults. It is...
Unable to process the form. Check for errors and try again.