Evaluation of 3D Overlay During Transjugular Intrahepatic Portosystemic Shunt (TIPS) Procedure

The goal of this study is to evaluate an alternate approach, which involves using a 3D puncture path overlay, to access the portal vein during a Transjugular Intrahepatic Portosystemic Shunt (TIPS) procedure. The study should determine if the alternate approach provides these benefits: improved safety of procedure, and reduced intervention time (including reduction of radiation exposure), which benefits both interventional radiologist and the patient. During a TIPS procedure, a shunt or stent (mesh tube) is passed down the jugular vein (the vein above the collarbone in the neck) using fluoroscopy (x-ray) guidance. The shunt then is inserted between the portal vein (vein that carries blood from the digestive organs into the liver) to a hepatic vein (vein that carries blood away from the liver back to the heart). In the standard approach, the interventional radiologist uses two-dimensional guidance (2D - having the dimensions of height and width only) to locate the path between the portal vein and hepatic vein. However, since these two veins do not connect, this method does not provide information on the three-dimensional (3D) relationship between the two veins. In the alternate approach, the physician will have the option of using 3D guidance to locate the path. An on-table limited (small field of view) CT scan, used in combination with FDA approved imaging software, will provide a 3D image demonstrating the relationship between the portal vein and the hepatic vein. The 3D image is overlaid on the standard live x-ray images to assist in needle guidance during the TIPS procedure. The CT scan performed will be in place of the angiograms that are typically performed. However, if the portal vein is not adequately seen in the CT images, the angiograms will be done and there will be no overlay. The procedure will proceed using the standard approach.