Helical CT angiography of transjugular intrahepatic portosystemic shunts

Shunt dysfunction due to draining hepatic vein and/or stent stenosis is a common long-term complication of transjugular intrahepatic portosystemic shunts (TIPS). Currently, Doppler sonography is the preferred modality for routine screening of TIPS for the detection of these complications. However, this method is time-consuming, highly operator-dependent, and difficult to perform because of the anatomic attributes of the cirrhotic liver. The use of helical CT angiography (HCTA) for imaging TIPS has been recently described. HCTA of TIPS is performed after a rapid i.v. injection of a bolus of low osmolality contrast medium, followed by helical data acquisition of the region of the shunt using thin sections. The data are then reprocessed a overlapping intervals and various reformations are obtained. Preliminary reports show the sensitivity and specificity of the helical CT angiography to be comparable with Doppler sonography.