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Computed tomographic (CT) colonography

Computed tomographic (CT) colonography, also called CTC, virtual colonoscopy (VC) or CT pneumocolon, is a powerful minimally invasive technique for colorectal cancer screening. Indications screening test for colorectal carcinoma colon evaluation after incomplete or unsuccessful conventional c...

CT enteroclysis

Computed tomographic (CT) enteroclysis refers to a hybrid technique that combines the methods of fluoroscopic intubation-infusion small bowel examinations with that of abdominal CT 1. Indications CT enteroclysis is complementary to capsule endoscopy in the elective investigation of small-bowel...

CT enterography

Computed tomographic (CT) enterography is a non-invasive technique for diagnosis of small bowel disorders. Advantages  evaluates the entire thickness of the bowel wall offers information about the surrounding mesentery, the mesenteric vasculature and the perienteric fat useful in the assessm...

Focussed Assessment with Sonography for Trauma (FAST) scan

Focussed Assessment with Sonography for Trauma (FAST) scan is a point-of-care ultrasound examination performed at the time of presentation of a trauma patient.  It is invariably performed by a clinician, who should be formally trained, and is considered as an 'extension' of the trauma clinical ...

Gastrointestinal MRI contrast agents

Gastrointestinal MRI contrast agents are varied and can be either positive or negative agents. Acceptance of the use of MRI in abdominal imaging has been limited in part by difficulty in distinguishing bowel from intra-abdominal masses and normal organs. The use of enteric contrast agents can ai...

Indium-111 OncoScint

Indium-111 OncoScint is a radiopharmaceutical used in SPECT imaging. It is a labelled monoclonal antibody that is directed against TAG-72, which is a tumour-associated antigen associated with ~95% of colorectal carcinomas and 100% of ovarian carcinomas 1,2. Background hepatic uptake limits sensi...

MR enterography

MR enterography is a new non-invasive technique for diagnosis of small bowel disorders. Indications The most common indication is to evaluate patients with Crohn disease (CD). Technique Actual procedure will vary depending on institutional protocol/guidelines but below is a typical descripti...


An octreoscan is a scinitigraphic study that uses 111In labelled octreotide which is a somatostatin analog. It is particularly useful for assessment of neuroendocrine tumours. Examples include: carcinoid tumour paraganglioma(s) glomus jugulare tumour glomus jugulotympanicum glomus vagale ...

Portosystemic shunt ratio

The portosystemic shunt ratio is a measure performed using ultrasound to quantify the abnormal flow of portal venous blood that is shunted away from the hepatic sinusoidal circulation in the context of a congenital portosystemic shunt 1. Ultrasound The ratio is determined using the following e...

Rectal cancer protocol (MRI)

Pelvic MRI protocol for rectal cancer includes: through tumour (always ensure planes are exactly perpendicular to the wall) three-plane T2 axial T1 narrow field of view images to be included overviews axial T2FS axial T1 See also MRI protocols


SeHCAT (23-seleno-25-homo-tauro-cholic acid) is a radiopharmaceutical used in the investigation of bile salt malabsorption, which is a cause of chronic diarrhoea.  Characteristics physical half-life: 118 days Uses, dosage and timings A capsule containing SeHCAT is ingested with water. The pa...

Tc-99m pertechnetate

Tc-99m pertechnetate is one of the technetium radiopharmaceuticals used in imaging of thyroid, colon, bladder and stomach. Characteristics photon energy: 140 keV physical half-life biological half-life: 6 hours normal distribution: stomach, thyroid, salivary glands, (testicles) excretion: ...

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...

Vicarious contrast material excretion

Vicarious contrast material excretion (VCME) defines excretion of water-soluble contrast material in a way other than via normal renal secretion.  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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