Mohan Lal Jayatilake1,2, Judd Storrs1,3,
Wen-Jang Chu1,3, Jing-Huei Lee1,4
1Center for Imaging
Research, University of Cincinnati, Cincinnati, OH, United States; 2Department
of Physics, University of Cincinnati, Cincinnati, OH, United States; 3Department
of Psychiatry & Behavioural Neuroscience, University of Cincinnati,
Cincinnati, OH, United States; 4School of Energy, Environmental,
Biological, & Medical Engineering, University of Cincinnati, Cincinnati,
OH, United States
Optimal image quality for MRI at high field requires a homogeneous RF (B1) field; however, dielectric properties of the human brain cause B1 field inhomogeneities in the periphery of the head. Selecting the appropriate permittivity and the quantity of material for B1 shim is essential. In this work we introduce a theoretical framework for determining the requisite dielectric constant of the passive shim material.