Articles

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16,879 results found
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5-F risk factors for cholelithiasis (mnemonic)

The 5-F rule refers to risk factors for the development of cholelithiasis in the event of upper abdominal pain: fair: more prevalent in the Caucasian population 1 fat: BMI >30 kg/m2 and hyperlipidemia 3,4 female fertile: one or more children forty: age ≥40 years cholelithiasis can occur in...
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5 gauss line

The 5 gauss line is the safety line drawn around the perimeter of the main magnet of the MRI scanner, specifying the distance at which the stray magnetic field is equivalent to 5 gauss (0.5 mT). Five gauss and below are considered 'safe' levels of static magnetic field exposure for the general ...
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5th metacarpal pit

The 5th metacarpal pit refers to the normal exaggeration of the pit-like depression in the head of fifth metacarpal 1.  Differential diagnosis It should not be mistaken for a boxer fracture (old or new) or an erosion.
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5-tier ACR system of radiologic breast findings (historical)

The 5-tier ACR system was a previously used system for the classification of radiologic breast findings, proposed by the American College of Radiology (ACR) ref. It is no longer in use having been superseded by the 6-tier BI-RADS classification system first published in 1992 1. Classification ...
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60/60 sign (echocardiography)

The 60/60 sign in echocardiography refers to the coexistence of a truncated right ventricular outflow tract acceleration time (AT <60 ms) with a pulmonary arterial systolic pressure (PASP) of less than 60 mmHg (but more than 30 mmHg). In the presence of right ventricular failure, it is consisten...
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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...
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Aarskog syndrome

Aarskog syndrome or Aarskog–Scott syndrome (also known as the facio-digito-genital syndrome) is a rare anomaly characterized by short stature in association with a variety of structural anomalies involving mainly the face, distal extremities, and external genitalia. Epidemiology Population pre...
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Aase-Smith syndrome

Aase-Smith syndrome (or Aase syndrome) is an extremely rare congenital disorder characterized by anemia and skeletal deformity. Epidemiology Aase-Smith syndrome has a prevalence of less than 1 per 1,000,000 persons. There have only been 20 reported cases. Clinical presentation congenital hyp...
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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. ...
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AAST kidney injury scale

The American Association for the Surgery of Trauma (AAST) renal injury scale, most recently updated in 2018, is the most widely used grading system for renal trauma. The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criteria for viscera...
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AAST liver injury scale

The AAST (American Association for the Surgery of Trauma) liver injury scale, revised in 2018, is the most widely used liver injury grading system 3. The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criteria for visceral injury 3. Cla...
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AAST spleen injury scale

The American Association for the Surgery of Trauma (AAST) splenic injury scale, revised in 2018, is the most widely used grading system for splenic trauma. The 2018 update incorporates "vascular injury" (i.e. pseudoaneurysm, arteriovenous fistula) into the imaging criteria for visceral injury 4...
Article

Abadie's sign (exopthalmos)

Abadie's sign is a medical sign of hyperthyroidism that is described by exophthalmos of both eyeballs, it is primarily caused by levator palpebrae superioris muscle spasm and appears as a clinically bulging eyes appearance 1. History and etymology Jean Marie Charles Abadie (1842–1932) was a Fr...
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ABC/2

ABC/2, also confusingly written as 1/2ABC in some literature, is a fast and simple method for estimating the volume of intracerebral hemorrhage (or any other ellipsoid lesion for that matter) which does not require volumetric 3D analysis or software. Intracerebral hemorrhage volume is an import...
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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,...
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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...
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Abdomen (KUB view)

The kidneys, ureters, bladder (KUB) radiograph is optimized for assessment of the urogenital system, and should not be confused with the AP supine abdomen view. However, in cases where the patient may have both gastrointestinal and urogenital abnormalities, all pathologies will still be reported...
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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...
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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...

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