Research on 7.0 T Magnetic Resonance Based Electrical Properties Tomography Based on Bloch-Siegert Shift

Magnetic resonance based electrical properties tomography (MREPT) is a different method from proton density imaging, Bloch-Siegert shift (BSS) is used in this paper to reconstruct the radiofrequency (RF) field amplitude and calculate the distribution of the permittivity constant. The phase of the RF field is approximated by the phase component of the magnetization intensity, and the conductivity distribution is calculated. In the experiment, Bruker 7.0 T magnetic resonance device was used to image two water models and in vivo Balb/c mice to obtain the image of electrical characteristics. Experimental results show that the Bloch-siegert B₁⁺ image is significantly more efficient than the double-angle B₁⁺ image. The study can provide a reference for selecting appropriate B₁ mapping technology for B₁ field imaging of electrical characteristics organizations, and provide basic research support for promoting the practical application of magnetic resonance characteristics.