Investigation of basis material decomposition imaging noise from different spectral CT parameters

We present a study of the influence of spectral CT parameters on image noise for different base-material decompositions observed by the variation of average standard deviation. The performances of the helical pitch, slice thickness, material density, ASiR algorithm, tube current and monochromatic energy have been discussed in general basis-material decomposition data acquired by a 64-row spectral computerized tomography. The image qualities for different base-material decompositions are presented. The results show that the monochromatic energy, ASiR algorithm and helical pitch influence the image noise at a certain low level, whereas the slice thickness and material density dominate the variation of the average SD value and the image noise. We demonstrate the image quality in current study is consistent with the standard water phantom research. The study indicates the importance of slice thickness as CT imaging parameter in the varied scan protocols for reducing image noise.