Alexey Tonyushkin1,2, Andrew J. M. Kiruluta1,2
1Radiology, Massachusetts
General Hospital, Harvard Medical School, Boston, MA, United States; 2Physics
Dept., Harvard University, Cambridge, MA, United States
Existing ultra-high field MR scanners allow propagation of TE and TM modes in high permittivity dielectrics, but the actual B1 field inside the dielectric can be hard to predict. Here, we present the analysis of B1-field map of traveling waves inside a cylindrical waveguide with a dielectric insert and explain features of B1 field by mode transformation to higher order ones. In practice, the modes diversity depends on the tissue efficient diameter, relative permittivity, conductivity, and the Larmor frequency. A more complicated case of heterogeneous axial symmetric dielectric can be also analyzed using effective permittivity and mode transformation approach.