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16 results found

SPACE (MRI sequence)

The SPACE MRI sequence, is a spin echo type MRI sequence, which creates high spatial resolution three-dimensional datasets. SPACE is an abbreviation for Sampling Perfection with Application optimized Contrast using different flip angle Evolution. The sequence was developed by Siemens. The SPACE...

CT chest abdomen-pelvis (protocol)

The CT chest-abdomen-pelvis protocol serves as an outline for an examination of the trunk covering the chest,  abdomen and pelvis. It is one of the most common CT examinations conducted in routine and emergencies. It can be combined with a CT angiogram. Note: This article aims to frame a genera...

CT abdomen-pelvis (protocol)

The CT abdomen-pelvis protocol serves as an outline for an examination of the whole abdomen including the pelvis. It is one of the most common CT protocols for any clinical questions related to the abdomen and/or in routine and emergencies. It forms also an integral part of trauma and oncologic ...

CT pancreas (protocol)

The CT pancreas protocol serves as an outline for a dedicated examination of the pancreas. As a separate examination, it is usually conducted as a biphasic contrast study and might be conducted as a part of other scans such as  CT abdomen-pelvis, CT chest-abdomen-pelvis. Note: This article aims...

CT liver volumetry (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...

MR elastography

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

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...

CT cholangiography (protocol)

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...

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 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 ...

Contrast-enhanced ultrasound

Contrast-enhanced ultrasound (CEUS) involves the administration of intravenous contrast agents consisting of microbubbles/nanobubbles of gas. Usecases liver hepatic metastasis cystadenoma/cystadenocarcinoma cholangiocarcinoma hepatocellular carcinoma hepatic adenoma focal nodular hyperpl...

Pulsatile portal venous flow

A pulsatile portal venous flow pattern is an abnormal form of portal venous flow and 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 pul...


Thorotrast is a suspension of radioactive thorium dioxide first produced in Germany in 1928, 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 thorium ...

Vicarious contrast media excretion

Vicarious contrast media excretion (VCME) refers to the excretion of intravascularly-administered water-soluble iodinated contrast media in a way other than via normal renal excretion. Epidemiology The most common vicarious excretion of water-soluble contrast material is via the liver, resulti...

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: 2 to 3 minutes normal distribution: liver: 85% spleen: 10% bone marrow: 5% excretion: hepatic target organ: liver, splee...

Comet tail artifact

The comet tail artifact is a grey scale ultrasound finding seen when small calcific / crystalline / highly reflective objects are interrogated and is believed to be a special form of reverberation artifact. It is similar to the color comet tail artifact and is seen in similar situations, althou...

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