Dual-Energy-based Beam Hardening Correction in Digital Volume Tomography (DVT)

In digital volume tomography (DVT) the image quality often suffers from beam hardening (BH) artifacts. The artifacts appear in the vicinity of strong attenuating objects like bones, teeth or implants which are densely positioned in the dentition. The polychromatic nature of x-ray radiation causes the BH artifacts. Several publications [1-3] have shown that suitable combinations of the lowand high-energy images of a dualenergy scan can provide images with different image characteristics like reduced BH and metal artifacts as well as an improved contrast-to-noise ratio (CNR). However, the solutions are mutually exclusive and only one parameter can be optimized at the same time. For example metal artifact reduced images always suffer from high noise [4] and require post-processing by noise reduction techniques like adaptive filtering, which might degrade spatial resolution. In the dental field, a special need for high spatial resolution and high contrasts exists [5].