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

Abstract

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.

Artificial intelligence enhances the accuracy of portal and hepatic vein extraction in computed tomography for virtual hepatectomy

“…Then, the PV and hepatic vein (HV) are identified and extracted using a certain threshold processing on the basis of an increased number of Hounsfield units in contrast to the liver parenchyma. 13 Liver PV and HV extraction remains challenging despite efforts to stretch the boundaries of 3D simulation technology because the PV and HV have similar Hounsfield characteristics on CT. 14 Current conventional algorithms for 3D simulation, however, still have difficulty clearly distinguishing between the PV and HV, and no study to date has evaluated the accuracy of 3D simulation software for extracting the PV and HV. Experienced liver surgeons must still correct and/or reconfirm the PV and HV vascular trees on the final 3D simulation image before beginning surgery.…”