Development of TEM Head-size Resonator for 3T MRI Head Coil

Ha, Seung Hoon; Choe, Bo Young; Kim, Yong Sik; Kim, Sung Eun; Suh, Tae Suk; Lee, Hyong Koo; Shinn, Kyung Sub; Lee, Heung Kyu

Abstract

PURPOSE
To apply a distributed circuit theory, to develop a head-size transverse electromagnetic(TEM) resonator coil for a home-built 3T whole-body MRI system and to report an efficiency of the coil.
MATERIALS AND METHODS
The dimension of TEM resonator with 16 cavity element, the diameter of copper rod was 0.63cm and its length was 13.75cm. As raw materials, the purity of copper rod was 98% and the dielectric constant of teflon was 2.08.
RESULTS
The TEM head-size resonator with 16cavity elements exhibiting 9-mode resonances was robust to the surrounding influences owing to the self-shielding structure. The isolation of quadrature with a human brain was 364 and the ratio of Q(unloaded/Q(loaded) was 2.9.
CONCLUSION
It was successfully demonstrated that the TEM head-size resonator with high Q factor can provide high quality MR images at 3T MRI system. Also, the TEM resonator coil has an advantage for a fine tune with length adjustment of each cavity elements. Thus, it is expected that the TEM resonator at 3T, even higher field could be used in the clinical and research studies in near future.