Spectral Computed Tomography: Influence of Contrast Medium for Calculation of Virtual Noncontrast-enhanced Images

The article is focused on the influence of contrast medium for calculation of virtual non-contrast-enhanced images (VNC) by spectral computed tomography (CT). True non-contrast-enhanced images (TNC) are weighted by Hounsfield unit HU and virtual native images are weighted by virtual Hounsfield unit $\mathrm{HU}^{*}$. Both types of images are compared by the signal-to-noise ratio (SNR) and $\mathrm{HU}/\mathrm{HU}^{*}$ ratio and in relation of used contrast agent.