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Abstract #0537

Working with Nulls, Reflections & Artifacts: Modified EM Mode Propagation in a Dielectric Waveguide at 21.1 T

Jose Antonio Muniz1, 2, Alexey A. Tonyushkin3, 4, Andrew J M Kiruluta3, 4, Samuel Colles Grant1, 2

1Center for Interdisciplinary Magnetic Resonance, National High Magnetic Field Laboratory, Tallahassee, FL, United States; 2Chemical & Biomedical Engineering, The Florida State University, Tallahassee, FL, United States; 3Radiology, Massachusetts General Hospital, Boston, MA, United States; 4Physics, Harvard University, Cambridge, MA, United States

Traveling wave MRI can be optimized by altering the dimensions and materials applied in waveguide construction. For a widebore magnet operating at 21.1 T (1H Larmor of 900 MHz), far field imaging and traveling waves cannot occur in an empty, bore-sized waveguide; however, the introduction of a concentric dielectric within the waveguide does support wave propagation. As such, there exists the opportunity to evaluate the dielectric as a means to alter electromagnetic modes. This study investigates optimization of ultra-high field traveling wave MRI at 21.1 T by varying the diameter, permittivity and geometric layout of dielectrics within a cylindrical waveguide.

Keywords

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