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11 results found

Contrast-enhanced ultrasound

Contrast-enhanced ultrasound involves the administration of intravenous contrast agents consisting of microbubbles/nanobubbles of gas. First-generation ultrasound contrast agents contained microbubbles of air that were dissolved in blood when exposed to acoustic pressure in the ultrasound field...

CT cholangiography

CT cholangiography is a technique of imaging the biliary tree with the usage of hepatobiliary excreted contrast. It is useful in delineating biliary anatomy, identifying a bile leak or looking for retained gallstones within the biliary system. Indications Second-line test (after ultrasound) wh...

CT liver volumetry (liver transplantation protocol)

CT liver volumetry is an essential imaging study in preoperative assessment for living donor liver transplantation. NB: This article is intended to outline some general principles of protocol design. The specifics will vary depending on CT hardware and software, radiologists' and referrers' pre...

Meglumine iotroxate (Biliscopin)

Meglumine iotroxate (BiliscopinTM) is an iodinated, intravenous contrast agent that is preferentially excreted into the biliary tree and is used in CT intravenous cholangiography. The typical dose is 100 mL Biliscopin (105 mg meglumine iotroxate/mL; 5.0 g iodine), which is administered via slow...

MR elastography

MR elastography (MRE) is an MRI technique that can be used to assess liver stiffness. This is useful to not only detect the development of fibrosis in diffuse liver disease, but also to quantify it and monitor liver fibrosis change with (or without) therapy. A main advantage over ultrasound ela...

MR liver iron quantification

MR liver iron quantification is a non-invasive means of measuring liver iron concentration, a key indicator in the management of patients with hemochromatosis (primary or secondary). Advantages Apart from being non-invasive, sampling occurs in a large cross-section of the liver, as opposed to ...

Pulsatile portal venous flow

A pulsatile portal venous flow pattern can result from both physiological and pathological causes. In well subjects mild pulsatility, or in rare situations, even marked pulsatility has been described, particularly in thin subjects, with a venous pulsatility index of >0.5 with an inverse correla...

Spectral Doppler (ultrasound)

Utilizing automated Fourier analysis to convert returning sound waves into a series of individual frequencies, spectral Doppler refers to ultrasound modalities which yield graphical representations of flow velocity over time.  Terminology The frequency of the sound waves returned to an ultraso...

Tc-99m sulfur colloid

Technetium-99m sulfur colloid is one of the technetium radiopharmaceuticals. Characteristics photon energy: 140 keV physical half-life: 6 hours biological half-life normal distribution: liver: 85% spleen: 10% bone marrow: 5% excretion: hepatic target organ: liver, spleen pharmacokinet...


Thorotrast is a suspension of radioactive thorium dioxide first produced in Germany in 1928 and used as a contrast agent until the 1950s. Its principal use was for cerebral angiography: 90% of the estimated 50,000-100,000 patients treated received it for this purpose. Umbrathor was another thori...

Vicarious contrast material excretion

Vicarious contrast material excretion (VCME) defines excretion of water-soluble contrast material in a way other than via normal renal excretion. The most common vicarious excretion of water-soluble contrast material is via the liver, resulting in increased bile density seen in the gallbladder. ...

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