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Abstract #2700

Improved Material for Passive RF Shimming with High Dielectric Pads

Wei Luo1, Yeun Chul Ryu2, Sukhoon Oh2, Zachary Herse2, Ketterman David Matthew1, Qing X. Yang2, Lanagan T. Michael1, Christopher M. Collins2

1Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, United States; 2Radiology, The Pennsylvania State University, Hershey, PA, United States

High dielectric materials (HDM) have been successfully used to improve the sensitivity and homogeneity of the RF magnetic field (B1+ and B1- field) in human MRI. Previously an HDM of a suspension made by calcium titanate (CaTiO3) powder in distilled or deuterated water was found advantageous for use in human brain MRI due to the strong effect of a minimal amount of this HDM. In this study, we developed and characterized a composite material using distilled water and sintered beads of BaTiO3. The bead/water composite showed a higher dielectric constant and lower conductivity compared to the BaTiO3 suspension, which should result in an even a higher effect per amount of material compared to the powder/water slurry.

Keywords

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