Quantitative evaluation of beam-hardening artefact correction in dual-energy CT myocardial perfusion imaging

Abstract

• Beam-hardening artefacts (BHA) cause interference with attenuation-based CT myocardial perfusion assessment (CTMPI). • BHA occur mostly in the posterobasal left ventricular wall. • Beam-hardening correction homogenized and decreased mean myocardial attenuation. • BHC can help avoid false-positive findings and increase specificity of static CTMPI.

Dual-Energy Heart CT: Beyond Better Angiography—Review

“…The beam hardening artifact occurs when a polychromatic X-ray beam passes through a high-density structure, which absorbs disproportionally more low-energy photons than high-energy ones. This disproportion generates hyper- and hypodense streaks on reconstructed images [ 5 , 69 , 72 ]. VMIs are much more resistant to these artifacts because they simulate images obtained with photons of single energy—is it not possible to harden that beam, only to attenuate it.…”

Principles and applications of dual source CT

“…More specifically, DSCT scanners are equipped with an iterative algorithm to correct for iodine-related beam hardening, which is separately applied to low-and high-kV images prior to material decomposition. The algorithm has been evaluated and found to significantly reduce beam hardening artifacts and improve DE results [45], such as virtual non- contrast, iodine and/or monoenergetic images, see Fig. 15 Object motion is yet another challenge for dual source DE CT because of the 90 • offset of the projections acquired by both measurement systems.…”

Advances in cardiac CT contrast injection and acquisition protocols

“…This can be used to optimize suboptimal opacification or lower the amount of iodine CM, e.g., in patients with impaired renal function (10,26,27) ( Figure 6). VMI at high energy levels are useful to reduce artifacts (28). Material decomposition has been shown to have potential benefits for mapping of iodine distribution in the myocardium as a quantitative marker for perfusion and blood volume (29) or reconstruction of virtual unenhanced images (30) (Figure 7), but is still under intense debate and ongoing research.…”