From the RSNA refresher courses: CT angiography: clinical applications in the abdomen

The development of spiral computed tomography (CT) and subsequently multidetector CT has provided unparalleled opportunities for advancement of CT technology and clinical applications. One of the most influential developments has been CT angiography, which is the use of thin-section CT combined with postprocessing of imaging data by using a variety of three-dimensional reconstruction techniques to produce vascular maps that equal or exceed those provided by classic angiography in many applications. In the evaluation of pancreatic disease, the use of multidetector CT angiography enables the radiologist to produce vascular maps that clearly show tumor invasion of vasculature and the relationship of vessels to pancreatic masses. Anatomic areas for which the three-dimensional display is especially helpful include the confluence of the portal vein and the superior mesenteric vein and the more distal portions of the portal vein. Preliminary studies indicate that CT angiography may prove beneficial in the evaluation of ischemic bowel and active Crohn disease. CT angiography has proved extremely valuable for applications such as preoperative planning for hepatic resection, preoperative evaluation and planning for liver transplantation, pretreatment planning for patients considered for hepatic arterial infusion chemotherapy, and pretreatment evaluation of portal vein patency for a variety of reasons. CT angiography can also provide supplemental information in patients with cirrhosis, upper gastrointestinal tract bleeding due to varices, or primary extrahepatic neoplasms.