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http://dx.doi.org/10.5370/KIEE.2014.63.3.404

The Comparison of Field Uniformity and SAR between TEM, Loop and Combined Elemented 16 Channel Transmit Arrays  

Ryu, Yeunchul (Dept. of Radiology, Pennsylvania State University)
Kim, Young Beom (Max-Planck-Institute for Neurological Research)
Publication Information
The Transactions of The Korean Institute of Electrical Engineers / v.63, no.3, 2014 , pp. 404-408 More about this Journal
Abstract
In this research we evaluate the excitation homogeneity and SAR of three different Tx arrays after B1+ Shimming in the human body at 3T. Through the simulations, we compared the field properties that are standard deviation and mean value of transverse magnetization for 1) strip line TEM array, 2) rectangular loop array, 3) combined array of strip line element and rectangular loop and shown the utilities of B1+ shimming in human body model. After B1+ shimming, it is evaluated four different types of SAR for body mesh through whole body simulation; those are average, maximum 1-cell, maximum 1-gram, and maximum 10-gram SAR. It appears that in this particular comparison an array based on strip line elements can produce better homogeneity and lower SAR than an array of rectangular loops or an array of combined elements (strip line and loop). While many factors are considered in designing coils for production, it is hoped that methods and results like these will be used in the future to guide decisions and maximize benefit.
Keywords
Transmission array; Body RF coil; Strip line TEM element; Rectangular loop element;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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