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18 results found

Denver shunt

A Denver shunt, or peritoneovenous shunt, is a device used to shunt ascites to the superior vena cava in patients with refractory ascites. The proximal end is located in the peritoneal cavity and the distal end in the superior vena cava, with a subcutaneous course in the anterior chest wall. It...

Endoscopic retrograde cholangiopancreatography

Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic and interventional procedure technique using both endoscopy and fluoroscopy for examination and intervention of the biliary tree and pancreatic ducts. It is typically performed by doctors with endoscopic qualifications (e.g. g...

Hepatic venous pressure gradient

Hepatic venous pressure gradient measurement is a safe and minimally invasive method to indirectly measure portal vein pressure in chronic liver disease patients suspected of developing portal vein hypertension.  Indications diagnosis of liver fibrosis and risk stratification identification o...

Irreversible electroporation

Irreversible electroporation (IRE), also known as non-thermal irreversible electroporation (NTIRE), is a non-invasive soft-tissue ablation technique used for tumor ablation in regions that require very high precision and preservation of surrounding collagenous structures (vessels and ducts) and ...

Liver and biliary interventional procedures

There is a wide range of liver and biliary interventional procedures, both diagnostic and therapeutic, most commonly using CT-guidance or ultrasound-guidance.   Vascular Interventions: transjugular intrahepatic portosystemic shunt (TIPS) transjugular liver biopsy (TJLB) Percutaneous interven...

Magnetic resonance cholangiopancreatography (MRCP)

Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging technique to visualize the intra and extrahepatic biliary tree and pancreatic ductal system. It can provide the diagnostic range equivalent to the ERCP and so it can replace the ERCP in high risk patients to avoid sign...

Esophageal varix

Esophageal varices describe dilated submucosal veins of the esophagus, and are an important portosystemic collateral pathway. They are considered distinct from gastric varices, which are less common. Epidemiology Esophageal varices are present in ~50% of patients with portal hypertension 1,2. ...

Percutaneous cholecystostomy

Percutaneous cholecystostomy is an image-guided placement of drainage catheter into gallbladder lumen. This minimally invasive procedure can aid the stabilization of a patient to enable a more measured surgical approach with time for therapeutic planning. A 2018 study 11 demonstrate no differen...

Percutaneous transhepatic biliary drainage

Percutaneous transhepatic biliary drainage is an interventional radiology procedure undertaken for those with biliary obstruction. It is almost exclusively performed in those with a malignant obstruction, such as cholangiocarcinoma, ampullary and pancreatic malignancies when retrograde access v...

Percutaneous transhepatic cholangiography

Percutaneous transhepatic cholangiography (PTC) is a radiographic technique employed in the visualization of the biliary tree and can be used as the first step in a number of percutaneous biliary interventions (e.g. percutaneous transhepatic biliary stent placement) Indications Purely diagnost...

Portal vein embolization

Portal vein embolization (PVE) is a technique used to selectively occlude the blood supply to one of the liver lobes, diverting portal blood flow to the other lobe, the future liver remnant (FLR). This diversion will increase the size of the post-hepatectomy future liver remnant (FLR) which imp...


Radioembolization is the delivery of radioactive microspheres to cancers using an endovascular approach. It is often performed as an outpatient procedure.  Indications hepatocellular carcinoma hepatic metastases from colorectal carcinoma Contraindications Absolute contraindications excessi...

Selective internal radiation therapy

Selective internal radiation therapy (SIRT), also know as hepatic radioembolization, is a relatively new and developing modality for treating non-resectable liver tumors. The procedure consists of a transcatheter injection of radioactive particles via the hepatic artery.  It is generally consid...

TIPS evaluation

TIPS evaluation is useful to ensure that the shunt is working properly and that no stenosis has occurred within the stent. Ultrasound is often used as a first-line modality. Radiographic features Ultrasound The normal TIPS should show color Doppler flow throughout its length. The in-stent vel...

Transcatheter arterial chemoembolisation

Transarterial chemoembolisation therapy (TACE) is a localized method of administrating chemotherapy directly to a liver tumor via a catheter study. The chemoembolic agent may be delivered via a mixture with LipiodolⓇ, known as conventional TACE, or as an injection of drug-eluting beads (DEB-TACE...

Transjugular intrahepatic portosystemic shunt

Transjugular intrahepatic portosystemic shunt (TIPS) is a treatment for portal hypertension in which direct communication is formed between a hepatic vein and a branch of the portal vein, thus allowing some proportion of portal flow to bypass the liver. The target portosystemic gradient after TI...

T tube cholangiogram

T-tube cholangiograms are a fluoroscopic study performed in the setting of hepatobiliary disease.  This technique has been largely superseded by MRCP and ERCP. Typically a T-shaped tube is left in the common bile duct at the time of surgery (e.g. cholecystectomy) and allows for exploration of t...

Ultrasound-guided biopsy

Ultrasound-guided biopsy is one form of image-guided biopsy, typically performed by a radiologist. It is the most common form of image-guided biopsy, offering convenience and real-time dynamic observation with echogenic markers on cannulae allowing for precise placement. It can potentially be u...

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