Ultrahigh-field MRI whole-slice and localized RF field excitations using the same RF transmit array

IEEE Trans Med Imaging. 2006 Oct;25(10):1341-7. doi: 10.1109/tmi.2006.880666.

Abstract

In this paper, a multiport driving mechanism is numerically implemented at ultra high-field (UHF) magnetic resonance imaging (MRI) to provide 1) homogenous whole-slice (axial, sagittal, or coronal) and 2) highly localized radio frequency (RF) field excitation within the same slices, all with the same RF transmit array (here chosen to be a standard transverse electromagnetic (TEM) resonator/coil). The method is numerically tested using a full-wave model of a TEM coil loaded with a high-resolution/18-tissue/anatomically detailed human head mesh. The proposed approach is solely based on electromagnetic and phased array antenna theories. The results demonstrate that both homogenous whole-slice as well as localized RF excitation can be achieved within any slice of the head at 7 T (298 MHz for proton imaging).

Publication types

  • Evaluation Study

MeSH terms

  • Algorithms
  • Anatomy, Cross-Sectional / instrumentation
  • Anatomy, Cross-Sectional / methods*
  • Brain / anatomy & histology*
  • Brain / physiology*
  • Brain Mapping / instrumentation
  • Brain Mapping / methods*
  • Computer Simulation
  • Equipment Design
  • Equipment Failure Analysis
  • Humans
  • Image Enhancement / instrumentation
  • Image Enhancement / methods*
  • Image Interpretation, Computer-Assisted / instrumentation
  • Image Interpretation, Computer-Assisted / methods*
  • Imaging, Three-Dimensional / instrumentation
  • Imaging, Three-Dimensional / methods
  • Magnetic Resonance Imaging / instrumentation
  • Magnetic Resonance Imaging / methods*
  • Male
  • Models, Neurological
  • Radio Waves
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Transducers