Simulations of the Stent Artifacts in Magnetic Resonance Imaging

This paper presents an approach to simulate the stent artifacts in magnetic resonance imaging (MRI) based on electromagnetic (EM) analysis. The metallic stent disturbs the static magnetic field (B0) and the radiofrequency (RF) field during the MRI procedure, which consequently results in susceptibility artifacts and RF shielding artifacts in MR image. Both the static and RF field distributions with the metallic stent in a uniform imaging phantom are calculated using the commercial finite element method (FEM) software JMAG 10.0. The images with stent artifacts are simulated by an MRI simulator, according to the calculated field distributions. The susceptibility artifacts and RF shielding artifacts are investigated at several conditions respectively. It can be concluded that the stent made of Ni-Ti alloy with a small magnetic susceptibility is promising to obtain the inside information with small susceptibility artifacts, and the stent with the open-cell design causes smaller RF shielding artifacts in MRI than the close-cell design.