Motion Artifacts in Three-dimensional CT Images / 实用放射学杂志

ABSTRACT

Objective To investigate the influence of physiological motions on three-dimensional (3D) CT images and the rules of motion artifacts.Methods A mathematical model of motion artifact was set up based on the principle of spiral scanning, hereby the geometrical distortion of 3D image was analyzed.Experiments were carried out with home-made phantoms on a CT scanner.Results The details of 3D images with trivial distortion were legible under static condition.On the contrary, distinct distortion occured under moving condition, and its degree increased with the pitch and motion period. The 3D images were varied with difference of the motion initial phases.Conclusion The distortion of 3D-CT image depends on the motion characters of scanned objects and scanning parameters such as pitch and slice thickness.