Hybrid Monopole/Loop Coil Array for Human Head MR Imaging at 7 T
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The monopole coil and loop coil have orthogonal radiofrequency (RF) fields and thus are intrinsically decoupled electromagnetically if they are laid out appropriately. In this study, we proposed a hybrid monopole/loop technique which could combine the advantages of both loop arrays and monopole arrays. To investigate this technique, a hybrid RF coil array containing four monopole channels and four loop channels was developed for human head magnetic resonance (MR) imaging at 7 T. In vivo MR imaging and g-factor results using monopole-only channels, loop-only channels and all channels of the hybrid array were acquired and evaluated. Compared with the monopole-only and loop-only channels, the proposed hybrid array has the higher signal-to-noise ratio (SNR) and better parallel imaging performance. Sufficient electromagnetic decoupling and diverse RF magnetic field (B1) distributions of monopole channels and loop channels may contribute to this performance improvement. From experimental results, the hybrid monopole/loop array has low g-factor and excellent SNR at both periphery and center of the brain, which is valuable for human head imaging at ultrahigh fields.
KeywordsHuman Head Hybrid Array Coil Element Loop Channel Ultrahigh Field
This work was supported in part by the Chinese National Major Scientific Equipment R&D Project (Grant No. ZDYZ2010-2), the Ministry of Science and Technology of China Grant (2012CB825500), the National Natural Science Foundation of China Grant (51228702), the Chinese Academy of Sciences Grants (XDB02010001, XDB02050001) and National Institutes of Health (NIH) R01EB008699.
- 17.X. Yan, R. Xue, X. Zhang, Quantum Imaging Med. Surg. 4(4), 225–231 (2014)Google Scholar
- 22.X. Yan, X. Zhang, L. Wei, R. Xue, Quant Imaging Med. Surg. 4(2), 79–86 (2014)Google Scholar
- 26.K. Lakshmanan, R. L. M. Cloos, D. Sodickson, G. Wiggins, in Proceedings of the 22nd Annual Meeting of ISMRM, Milan (2014), p. 397Google Scholar
- 27.J. Paska1, C. Leussler, in Proceedings of the 16th Annual Meeting of ISMRM, Toronto (2008), p. 149Google Scholar
- 29.Z. Xie, X. Zhang, in Proceedings of the 16th Annual Meeting of ISMRM, Toronto (2008), p. 1068Google Scholar
- 30.Z. Xie, X. Zhang, in Proceedings of the 16th Annual Meeting of ISMRM, Toronto (2008), p. 2972Google Scholar
- 33.X. Yan, X. Zhang, L. Wei, R. Xue, Appl. Magn. Reson. (2014). doi: 10.1007/s00723-014-0612-9