Dual-energy derived virtual nonenhanced computed tomography imaging: current status and applications.

Radiation exposure is a growing concern, and computed tomography is a main contributor to overall radiation dose in American patients. Dual-energy computed tomography, by allowing virtual nonenhanced (VNE) imaging, may obviate the need for image acquisition during a true nonenhanced phase when multiphase studies are needed, thereby reducing radiation exposure. Various groups have reported on the technical feasibility and clinical applicability of VNE imaging in the kidney, liver, lung, brain, and aorta. VNE is consistently reported to be both feasible and clinically relevant, although both hardware and postprocessing capabilities currently pose various specific challenges. We review the current state of VNE imaging and discuss some challenges to its future application.