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http://dx.doi.org/10.7742/jksr.2022.16.6.761

Improvement of High Permittivity Pads for Areas with Generally Low Signal Sensitivity at 7T MRI  

Yong-Tae, Kim (Lee Gil Ya Cancer and Diabetes Institute & Department of Pre-Medicine, Gachon University School of Medicine)
Hyeon-Man, Baek (Departmnet of Health Science and Technology, GAIST, Gachon University)
Publication Information
Journal of the Korean Society of Radiology / v.16, no.6, 2022 , pp. 761-769 More about this Journal
Abstract
Pads with high dielectric materials have been used in a variety of applications to locally improve the field sensitivity and homogeneity of RF pulses in clinical MRI studies. In this study, we aimed to improve such pads in consideration of the practical problems associated with the application of actual clinical images. A high permittivity pad to increase the attenuated B1 field strength was fabricated and tested in 7T MRI. Sim4Life simulation and experimental results show stronger and relatively uniform B1 near field. In order to improve the image quality in the whole cerebellum, known as a region with low sensitivity, a guide was made to reduce the mechanical change of the pad. In order to improve the wearing comfort, the pad was designed by dividing it into upper and lower parts. The facial pad showed an overall signal increase effect in areas such as the turbinate in the nasal cavity. Signal increase was expected in areas such as the frontal lobe and eyes, but the effect was either insignificant or it was difficult to see the effect in the imaging protocol. In conclusion, this paper showed a cerebellar-optimized pad with an improved nasal signal while maintaining its effectiveness.
Keywords
Sim4Life; Perovskite; Dielectric shimming; 7T MRI System; B1 field;
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