Demonstration of hepatic veins by computed tomography using axial and angulated scanning

The main hepatic veins run obliquely into the inferior caval vein. They are often poorly demonstrated on conventional axial computed tomography (CT) performed with a vertical gantry. In order to determine whether CT with caudal tilting of the gantry could improve demonstration of the hepatic veins, 30 consecutive patients of whom 20 had focal lesions in the liver were examined with both a vertical and a 20 degree caudally tilted gantry. As a reference group, 10 patients were examined with a 20 degree cranially tilted gantry. In 14/30 (47%) of the non-enhanced examinations caudally angulated CT demonstrated the hepatic veins better than axial CT, while axial CT was the better technique in one patient. No additional tumors were detected with either technique, but the caudal angulation improved the anatomical location of tumors due to a better demonstration of their relation to hepatic veins. CT with cranial angulation did not in any patient improve the demonstration of veins when compared to axial CT. Angulated CT also included examination with contrast enhancement using bolus technique. In 20 out of 27 (74%) examinations with a caudally tilted gantry and contrast enhancement considered optimal for tumor detection, veins containing contrast medium were depicted for an anatomical description. Caudally angulated CT is a non-invasive technique which should be performed in patients in whom liver resection is considered.