Vol. 98

Front:[PDF file] Back:[PDF file]
Latest Volume
All Volumes
All Issues
2020-01-09

Port Decoupling Vs Array Elements Decoupling for Tx/Rx System at 7-Tesla Magnetic Resonance Imaging

By Ashraf Abuelhaija, Sanaa Salama, and Tarik Baldawi
Progress In Electromagnetics Research C, Vol. 98, 213-224, 2020
doi:10.2528/PIERC19091205

Abstract

Symmetrically excited meandered microstrip line RF coil elements are widely utilized in multichannel approaches which have been proposed to be integrated in ultra-high field MRI system (i.e., 7T and higher). These elements have demonstrated strong magnetic field in the deep areas in the object under imaging. Designing a radio frequency (RF) coil array that employs these elements without decoupling networks might cause non-optimized driving performance of coil array which in turn result in non-clear image. In this paper, two different methods of decoupling have been studied: port decoupling and array elements decoupling. For port decoupling, the coil elements have been designed at Larmor frequency (297.3 MHz) whereas for array elements decoupling, the coil elements have been designed at higher frequencies but matched at Larmor frequency. Port decoupling does not always mean element decoupling. Conventional decoupling methods, such as single capacitor or inductor, face challenges to realize the coil element decoupling for meandered microstrip arrays. An optimized reactive (T-shaped) network is needed in order to achieve element decoupling which in turn prevents distortion of the EM field. All simulation results have been obtained using the CST time domain solver (CST AG, Darmstadt, Germany).

Citation


Ashraf Abuelhaija, Sanaa Salama, and Tarik Baldawi, "Port Decoupling Vs Array Elements Decoupling for Tx/Rx System at 7-Tesla Magnetic Resonance Imaging," Progress In Electromagnetics Research C, Vol. 98, 213-224, 2020.
doi:10.2528/PIERC19091205
http://www.jpier.org/PIERC/pier.php?paper=19091205

References


    1. Yacoub, E., A. Shmuel, J. Pfeuffer, P. F. van de Moortele, G. Adriany, P. Andersen, J. T. Vaughan, H. Merkle, K. Ugurbil, and X. Hu, "Imaging brain function in humans at 7 Tesla," Magnetic Resonance in Medicine, Vol. 45, No. 4, 588-594, 2001.

    2. Vaughan, J. T., M. Garwood, C. M. Collins, W. Liu, L. DelaBarre, G. Adriany, P. Andersen, H. Merkle, R. Goebel, M. B. Smith, and K. Ugurbil, "7 T vs. 4 T: RF power, homogeneity, and signal-to-noise comparison in head images," Magnetic Resonance in Medicine, Vol. 46, No. 1, 24-30, 2001.

    3. Collins, C. M. and M. B. Smith, "Signal-to-noise ratio and absorbed power as functions of main magnetic field strength, and definition of 90 RF pulse for the head in the birdcage coil," Magnetic Resonance in Medicine, Vol. 45, No. 4, 684-691, 2001.

    4. Hoult, D. I., "Insight into RF power requirements and B1 field homogeneity for human MRI via rigorous FDTD approach," Journal of Magnetic Resonance Imaging, Vol. 25, No. 6, 1235-1247, 2007.

    5. Brown, R. W., E. M. Haacke, M. A. Martens, J. L. Patrick, and F. R. Zypman, "A layer model for RF penetration, heating, and screening in NMR," Journal of Magnetic Resonance Imaging, Vol. 80, No. 2, 225-247, 1988.

    6. Wang, Z., J. C. Lin, W. Mao, W. Liu, M. B. Smith, and C. M. Collins, "SAR and temperature: Simulations and comparison to regulatory limits for MRI," Journal of Magnetic Resonance Imaging, Vol. 26, No. 2, 437-41, 2007.

    7. Wang, Z., J. C. Lin, W. Mao, W. Liu, M. B. Smith, and C. M. Collins, "Combination of optimized transmit arrays and some receive array reconstruction methods can yield homogeneous images at very high frequencies," Magnetic Resonance in Medicine, Vol. 54, No. 6, 1327-1332, 2005.

    8. Mao, W., M. B. Smith, and C. M. Collins, "Exploring the limits of RF shimming for high-field MRI of the human head," Magnetic Resonance in Medicine, Vol. 56, No. 4, 918-922, 2006.

    9. Katscher, U., P. Börnert, C. Leussler, and J. S. van Den Brink, "Transmit SENSE," Magnetic Resonance in Medicine, Vol. 49, No. 1, 144-150, 2003.

    10. Grissom, W., C. Y. Yip, Z. Zhang, V. A. Stenger, J. A. Fessler, and D. C. Noll, "Spatial domain method for the design of RF pulses in multicoil parallel excitation," Magnetic Resonance in Medicine, Vol. 56, No. 3, 620-629, 2006.

    11. Orzada, S., S. Maderwald, B. A. Poser, A. K. Bitz, H. H. Quick, and M. E. Ladd, "RF excitation using time interleaved acquisition of modes (TIAMO) to address B1 inhomogeneity in high-field MRI," Magnetic Resonance in Medicine, Vol. 64, No. 2, 327-333, 2010.

    12. Wiggins, G. C., A. Potthast, C. Triantafyllou, C. J. Wiggins, and L. L. Wald, "Eight-channel phased array coil and detunable TEM volume coil for 7 T brain imaging," Magnetic Resonance in Medicine, Vol. 54, No. 1, 235-240, 2005.

    13. Avdievich, N. I., "Transceiver-phased arrays for human brain studies at 7 T," Applied Magnetic Resonance, Vol. 41, No. 2-4, 483-506, 2011.

    14. Kraff, O., A. K. Bitz, S. Kruszona, S. Orzada, L. C. Schaefer, J. M. Theysohn, S. Maderwald, M. E. Ladd, and H. H. Quick, "An eight-channel phased array RF coil for spine MR imaging at 7 T," Investigative Radiology, Vol. 44, No. 11, 734-740, 2009.

    15. Salama, S., "Design of a rectangular loop-shape RF coil for 7-Tesla magnetic resonance imaging," Microwave Conference (APMC), 1044-1047, 2017.

    16. Aussenhofer, S. A. and A. G. Webb, "An eight-channel transmit/receive array of TE01 mode high permittivity ceramic resonators for human imaging at 7 T," Journal of Magnetic Resonance, Vol. 243, 122-129, 2014.

    17. Brunner, D. O., N. De Zanche, J. Froehlich, D. Baumann, and K. Pruessmann, "A symmetrically fed microstrip coil array for 7 T," Proc. 15th Annu. Meeting ISMRM, 2007.

    18. Orzada, S., A. Bahr, and T. Bolz, "A novel 7 T microstrip element using meanders to enhance decoupling," Proc. 16th Annu. Meeting ISMRM, 2008.

    19. Zhang, X., K. Ugurbil, and W. Chen, "Microstrip RF surface coil design for extremely high-field MRI and spectroscopy," Magnetic Resonance in Medicine, Vol. 46, No. 3, 443-450, 2001.

    20. Zhang, X., K. Ugurbil, R. Sainati, and W. Chen, "An inverted-microstrip resonator for human head proton MR imaging at 7 Tesla," IEEE Transactions on Biomedical Engineering, Vol. 52, No. 3, 495-504, 2005.

    21. Raaijmakers, A. J. E., O. Ipek, D. W. Klomp, C. Possanzini, P. R. Harvey, J. J. Lagendijk, and C. A. van Den Berg, "Design of a radiative surface coil array element at 7 T: The single-side adapted dipole antenna," Magnetic Resonance in Medicine, Vol. 66, No. 5, 1488-1497, 2011.

    22. Hong, S. M., J. H. Park, M. K. Woo, Y. B. Kim, and Z. H. Cho, "New design concept of monopole antenna array for UHF 7 T MRI," Magnetic Resonance in Medicine, Vol. 71, No. 5, 1944-1952, 2014.

    23. Sánchez-Heredia, J. D., J. Avendal, A. Bibic, and B. K. Lau, "Radiative MRI coil design using parasitic scatterers: MRI Yagi," IEEE Transactions on Antennas and Propagation, Vol. 66, No. 3, 1570-1575, 2018.

    24. Lee, R. F., R. O. Giaquinto, and C. J. Hardy, "Coupling and decoupling theory and its application to the MRI phased array," Magnetic Resonance in Medicine, Vol. 48, No. 1, 203-213, 2002.

    25. Mahmood, Z., B. Guérin, E. Adalsteinsson, L. L. Wald, and L. Daniel, "Design of a robust decoupling matrix for high field parallel transmit arrays," Proc. Intl. Soc. Mag. Reson. Med., 2014.

    26. Jevtic, J., "Ladder networks for capacitive decoupling in phased-array coils," Proceedings of the Proceedings of the, 2001.

    27. Wu, B., X. Zhang, P. Qu, and G. X. Shen, "Design of an inductively decoupled microstrip array at 9.4 T," Journal of Magnetic Resonance, Vol. 182, No. 1, 126-132, 2006.

    28. Salama, S., "Reactive-element based decoupling network for a two-element MRI phased array," Journal of King Saud University-Engineering Sciences, 2018.

    29. Li, Y., Z. Xie, Y. Pang, D. Vigneron, and X. Zhang, "ICE decoupling technique for RF coil array designs," Medical Physics, Vol. 38, No. 7, 4086-4093, 2011.

    30. Abuelhaija, A., S. Orzada, and K. Solbach, "Parasitic element based decoupling of 7 Tesla MRI coil array," Antennas and Propagation Conference (LAPC), 2015.

    31. Yan, X., X. Zhang, L. Wei, and R. Xue, "Magnetic wall decoupling method for monopole coil array in ultrahigh field MRI: A feasibility test," Quantitative Imaging in Medicine and Surgery, Vol. 4, No. 2, 79, 2014.

    32. Hurshkainen, A. A., T. A. Derzhavskaya, S. B. Glybovski, I. J. Voogt, I. V. Melchakova, C. A. van Den Berg, and A. J. Raaijmakers, "D element decoupling of 7 T dipole body arrays by EBG metasurface structures: Experimental verification," Journal of Magnetic Resonance, Vol. 269, 87-96, 2016.

    33. Lee, W., E. Boskamp, T. Grist, and K. Kurpad, "Radiofrequency current source (RFCS) drive and decoupling technique for parallel transmit arrays using a high-power metal oxide semiconductor field-effect transistor (MOSFET)," Magnetic Resonance in Medicine, Vol. 62, No. 1, 218-228, 2009.

    34. Chu, X., X. Yang, Y. Liu, J. Sabate, and Y. Zhu, "Ultra-low output impedance RF power amplifier for parallel excitation," Magnetic Resonance in Medicine, Vol. 61, No. 4, 952-961, 2009.

    35. Abuelhaija, A. and K. Solbach, "An ultra-low output impedance power amplifier for Tx array in 7-Tesla magnetic resonance imaging," International Conference on Microwave Science and Technology, 2015.

    36. Hoult, D. I., G. Kolansky, D. Kripiakevich, and S. B. King, "The NMR multi-transmit phased array: A Cartesian feedback approach," Journal of Magnetic Resonance, Vol. 171, No. 1, 64-70, 2004.

    37. Abuelhaija, A., K. Solbach, and A. Buck, "Power amplifier for magnetic resonance imaging using unconventional Cartesian feedback loop," German Microwave Conference (GeMiC), 2015.

    38. Abuelhaija, A., "Power amplifier for magnetic resonance imaging using unconventional cartesian feedback loop,", Ph.D thesis, Duisburg-Essen University, Duisburg, 2016.

    39. Solbach, K., A. Abuelhaija, and S. Shooshtary, "Near-magnet power amplifier with built-in coil current sensing," 22nd Proc. Intl. Soc. MRM, 2014.

    40. Salim, M., A. C. Ozen, M. Bock, and E. Atalar, "Active decoupling of transmit and receive coils for full-duplex MRI,", arXiv preprint arXiv: 1810.10973, 2018.

    41. Vaughan, J. T., H. P. Hetherington, J. O. Otu, J. W. Pan, and G. M. Pohost, "High frequency volume coils for clinical NMR imaging and spectroscopy. Magnetic resonance in medicine," Magnetic Resonance in Medicine, Vol. 32, No. 2, 206-218, 1994.

    42. Adriany, G., A. Gozubuyuk, J. Ritter, C. Snyder, P. F. van de Moortele, S. Moeller, J. T. Vaughan, and K. Ugurbil, "A 32 channel lattice transmission line array for parallel MRI," Proc. 14th Annual Meeting of the ISMRM, 2006.

    43. Rietsch, S. H., H. H. Quick, and S. Orzada, "Impact of different meander sizes on the RF transmit performance and coupling of microstrip line elements at 7 T," Medical Physics, Vol. 42, No. 8, 4542-4552, 2015.

    44. Chen, Z., K. Solbach, D. Erni, and A. Rennings, "Dipole RF element for 7 Tesla magnetic resonance imaging with minimized SAR," 7th European Conference on Antennas and Propagation (EuCAP), 2013.

    45. Saleh, G., K. Solbach, A. Rennings, and Z. Chen, "SAR reduction for dipole RF coil element at 7 Tesla by using dielectric overlay," Loughborough Antennas and Propagation Conference (LAPC 2012), 2012.

    46. Abuelhaija, A., K. Solbach, and S. Orzada, "Comprehensive study on coupled meandered microstrip line RF coil elements for 7-Tesla magnetic resonance imaging," 9th European Conference on Antennas and Propagation (EuCAP), 2015.

    47. Orzada, S., K. Solbach, M. E. Ladd, and A. K. Bitz, "Comparison of three different microstrip transmit elements for use in multichannel Tx/Rx body coils at 7 Tesla," 22nd Proc. Intl. Soc. MRM, 2014.

    48. Orzada, S., O. Kraff, L. C. Schäfer, I. Brote, A. Bahr, T. Bolz, S. Maderwald, M. E. Ladd, and A. K. Bitz, "8-channel transmit/receive head coil for 7 T human imaging using intrinsically decoupled strip line elements with meanders," Proc. Int. Soc. Magn. Reson. Med., 2009.

    49. Wu, B., C. Wang, D. A. Kelley, D. Xu, D. B. Vigneron, S. J. Nelson, and X. Zhang, "Shielded microstrip array for 7 T human MR imaging," IEEE Transactions on Medical Imaging, Vol. 29, No. 1, 179-184, 2010.

    50. Orzada, S., A. K. Bitz, S. Johst, M. Gratz, M. N. Völker, O. Kraff, A. Abuelhaija, T. M. Fiedler, K. Solbach, and H. H. Quick, "Analysis of an integrated 8-channel Tx/Rx body array for use as a body coil in 7-Tesla MRI," Frontiers in Physics, Vol. 5, 17, 2017.

    51. Orzada, S., A. K. Bitz, O. Kraff, M. Oehmigen, M. Gratz, S. Johst, M. N. Völker, S. H. G. Rietsch, M. Flöser, T. Fiedler, and S. Shooshtary, "A 32-channel integrated body coil for 7 Tesla whole-body imaging," Proceedings of the 24th Annual Meeting of ISMRM, 2016.

    52. Orzada, S., K. Solbach, M. Gratz, S. Brunheim, T. M. Fiedler, S. Johst, A. K. Bitz, S. Shooshtary, A. Abuelhaija, M. N. Voelker, and S. H. R, "A 32-channel parallel transmit system add-on for 7 T MRI," PloS One, Vol. 14, 9, 2019.

    53. Abuelhaija, A., S. Salama, and O. Nashwan, "Decoupling network for Tx/Rx body coil for 7 Tesla MRI," Turkish Journal of Electrical Engineering and Computer Sciences, Vol. 27, 6, 2019.

    54. Chen, S. C., Y. S. Wang, and S. J. Chung, "A decoupling technique for increasing the port isolation between two strongly coupled antennas," IEEE Transactions on Antennas and Propagation, Vol. 56, No. 12, 3650-3658, 2008.

    55. Coetzee, J. C. and Y. Yu, "Closed-form design equations for decoupling networks of small arrays," Electronics Letters, Vol. 44, No. 25, 1441-1442, 2008.

    56. Li, L., S. Venkatasubramanian, A. Lehtovuori, C. Icheln, M. Heino, and K. Haneda, "T-shaped decoupling network for wideband isolation improvement between two strongly coupled antennas," Loughborough Antennas and Propagation Conference (LAPC), 2015.

    57. Balanis, C. A., Antenna Theory: Analysis and Design, Microstrip Antennas3rd Ed., , John Wiley and Sons, 2005.