Simulations of high permittivity materials for 7 T neuroimaging and evaluation of a new barium titanate-based dielectric

摘要: High permittivity “dielectric pads” have been shown to increase image quality at high magnetic fields in regions of low radiofrequency transmit efficiency. This article presents a series electromagnetic simulations determine the effects pad size and geometry, relative value, as well thickness on for neuroimaging 7 T. For 5-mm thick pad, there is virtually no effect field values lower than ∼90. Significant improvements are found between 90 ∼180. If increased above ∼180 then areas very efficiency produced. 1-cm corresponding numbers ∼60 ∼120, respectively. Based upon findings, new material (barium titanate, ∼150) used produce thin (∼5 mm) dielectric pads which can easily be placed within standard receive head array. Experimental measurements sensitivities, acquisition T2- T-weighted images show promise this approach. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.