Investigation of the Utility and Safety of Dynamic Computed Tomography with Vasodilators

Background: Dynamic computed tomography (CT) angiography is useful for evaluating of hepatic vascularity. Although vasodilators increase hepatic blood flow, the utility of dynamic CT with vasodilators is unclear. Here we investigated the utility and safety of dynamic CT with vasodilators. Methods: A prospective case-control radiographic evaluation using abdominal dynamic CT with and without vasodilator was performed at a single center between October 2015 and September 2016. We compared the CT values in Hounsfield units of the aorta; celiac artery; and common, right, and left hepatic arteries in the arterial phase and the main trunk; right and left branches of the portal vein; and right, middle, and left hepatic veins in the portal phase with and without vasodilators. The region of interest was set in each element of the liver vasculature. Four radiological technologists independently and visually compared the scores of the portal vein (P-score) and hepatic vein (V-score) on a 5-point scale with and without vasodilators. Results: The CT values of arteries and veins using vasodilators were significantly higher than those without vasodilators. With and without vasodilators, the P-scores were 3.1 ± 1.2 and 4.0 ± 1.1 (P < 0.05) and the V-scores were 3.3 ± 1.4 and 4.3 ± 1.0 (P < 0.05). Only one patient with vasodilator use had transient hypotension and recovered immediately without medication. Conclusion: Dynamic CT with vasodilators can provides better visualization of vascular structures.