Enhancing virtual monoenergetic images for non-congruent dual-energy CT projection data

This study investigates the application of joint bilateral filtering for noise reduction in fast kVp switching dualenergy computed tomography (DECT). A high resolution image is calculated from non-congruent data of two scans with different energy spectra. This image guides the denoising process of the material decomposition that are used to obtain virtual monoenergetic images (VMIs). The performance of the filter was evaluated in terms of standard deviations on measured data. The proposed filter significantly reduces noise in the VMIs and preserves edges. Furthermore, the simple implementation of the filter can be used for various scanning protocols.