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Comparison of 16-channel asymmetric sleeve antenna and dipole antenna transceiver arrays at 10.5 Tesla MRI

Myung Kyun Woo, Lance Dela Barre, Matt Waks, Jingu Lee, Russell Luke Lagore, Steve Jungst, Andrea Grant, Yigitcan Eryaman, Kamil Ugurbil, Gregor Adriany
2020 IEEE Transactions on Medical Imaging  
Multi-element transmit arrays with low peak 10 g specific absorption rate (SAR) and high SAR efficiency (defined as (B1+/√peakSAR10g) are essential for ultra-high field (UHF) magnetic resonance imaging  ...  (MRI) applications.  ...  INTRODUCTION agnetic resonance imaging (MRI) at ultra-high fields (UHF, defined as ≥7 tesla (T)) are increasingly pursued for biomedical research due to gains in signal-to-noise [1] [2] [3] [4] and,  ... 
doi:10.1109/tmi.2020.3047354 pmid:33360987 pmcid:PMC8078892 fatcat:rpt2tqqi7fgtlkwvc3y6pb3kve

Effect of RF coil excitation on field inhomogeneity at ultra high fields: a field optimized TEM resonator

Tamer S Ibrahim, Robert Lee, Brian A Baertlein, Amir M Abduljalil, Hui Zhu, Pierre-Marie L Robitaille
2001 Magnetic Resonance Imaging  
In this work, computational methods were utilized to optimize the field produced by the transverse electromagnetic (TEM) resonator in the presence of the human head at 8 Tesla.  ...  Optimization was achieved through the use of the classical finite difference time domain (FDTD) method and a TEM resonator loaded with an anatomically detailed human head model with a resolution of 2 mm  ...  Introduction In high field (Ͼ4 Tesla) MRI systems, a major challenge is the design of RF coils that exhibit a good signal to noise ratio, transverse magnetic (B 1 ) field uniformity, and low specific absorption  ... 
doi:10.1016/s0730-725x(01)00404-0 pmid:11804762 fatcat:xccxpzaknfgqjgesjdvhazakne

Endourethral MRI

Harald H. Quick, Jean-Michel Serfaty, Harpreet K. Pannu, Rene Genadry, Christopher J. Yeung, Ergin Atalar
2001 Magnetic Resonance in Medicine  
This study introduces an endourethral approach for ultra-high-resolution MRI of the female urethra and the periurethral tissues.  ...  To this end, two different radiofrequency (RF) receiver coil designs for an endourethral insertion have been developed: a single-loop coil and a phased array/quadrature coil.  ...  ., for providing the flexible coil circuits and fabricating the prototype coil used in the in vivo pig experiments. Ergin Atalar is a co-founder and consultant of Surgi-Vision, Inc.  ... 
doi:10.1002/1522-2594(200101)45:1<138::aid-mrm1018>3.0.co;2-g pmid:11146495 fatcat:kkykrmca2ffrdhoyngf3cjl3km

Shielded Microstrip Array for 7T Human MR Imaging

Bing Wu, Chunsheng Wang, D.A.C. Kelley, Duan Xu, D.B. Vigneron, S.J. Nelson, Xiaoliang Zhang
2010 IEEE Transactions on Medical Imaging  
The high-frequency transceiver array based on the microstrip transmission line design is a promising technique for ultrahigh field magnetic resonance imaging (MRI) signal excitation and reception.  ...  In this paper, we present an approach to improving the performance of microstrip transceiver arrays by introducing RF shielding outside the microstrip array and the feeding coaxial cables.  ...  Lu for manuscript editing and proofreading.  ... 
doi:10.1109/tmi.2009.2033597 pmid:19822470 pmcid:PMC2834268 fatcat:7ldq7tc4rbgyrhgodm6ncwly74

A 16-Channel Dipole Antenna Array for Human Head Magnetic Resonance Imaging at 10.5 Tesla

Myung Kyun Woo, Lance DelaBarre, Matt Waks, Jerahmie Radder, Uk-Su Choi, Russell Lagore, Kamil Ugurbil, Gregor Adriany
2021 Sensors  
For ultra-high field and frequency (UHF) magnetic resonance imaging (MRI), the associated short wavelengths in biological tissues leads to penetration and homogeneity issues at 10.5 tesla (T) and require  ...  antenna transmit arrays for efficiently generated 447 MHz B1+ fields (defined as the transmit radiofrequency (RF) magnetic field generated by RF coils).  ...  , MN, USA) for their help with 3D printing, discussion and feedback.  ... 
doi:10.3390/s21217250 pmid:34770558 pmcid:PMC8587099 fatcat:rqvu5xn75bfazavu7jd7kgx7ce

Mitigation of B1+ inhomogeneity for ultra-high-field magnetic resonance imaging: hybrid mode shaping with auxiliary EM potential

Minkyu Park, Hansol Noh, Namkyoo Park
2020 Scientific Reports  
Here, we show that the same concept provides an opportunity for the seemingly different field of ultra-high-field MRI, addressing transmit RF magnetic field (B1+) inhomogeneity.  ...  In this work, treating the human phantom as a resonator, we employ an evanescently coupled high-index cladding layer to study the effects of the auxiliary potential on shaping the B1+ field distribution  ...  Here, we show that the same concept provides an opportunity for the seemingly different field of ultra-high-field MRI, addressing transmit RF magnetic field (B 1 + ) inhomogeneity.  ... 
doi:10.1038/s41598-020-68651-6 pmid:32678182 fatcat:hzgf2iqucjcn5dhsnaplr7worm

Monopole antenna array design for 3 T and 7 T magnetic resonance imaging

A. S. M. Zahid Kausar, David C. Reutens, Ewald Weber, Viktor Vegh, Xiaoliang Zhang
2019 PLoS ONE  
Ultra-high field magnetic resonance imaging poses a number of challenges for robust radio frequency coil designs.  ...  A monopole antenna array can potentially overcome key limitations of birdcage coil designs and may provide a useful radio frequency coil for brain imaging.  ...  Acknowledgments The authors would like to thank the Australian Research Council for linkage project funding (LP130100703).  ... 
doi:10.1371/journal.pone.0214637 pmid:30933999 pmcid:PMC6443181 fatcat:ce5elkeavff2dfxl5aox3ejytu

2019 Index IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology Vol. 3

2019 IEEE Journal of Electromagnetics RF and Microwaves in Medicine and Biology  
., +, JERM March 2019 33-40 RF Aspects of High-Field Magnetic Resonance Imaging (HF-MRI): Recent Advances.  ...  ., +, JERM Dec. 2019 247-253 Transmitters RF Aspects of High-Field Magnetic Resonance Imaging (HF-MRI): Recent Advances.  ... 
doi:10.1109/jerm.2019.2961617 fatcat:dfd7p3illffq3fu5ajeu4w7boa

Hardware of MRI System [chapter]

Qiuliang Wang
2019 Nuclear Magnetic Resonance [Working Title]  
The development of MRI system toward high magnetic field strength will acquire high signal-to-noise ratio (SNR) and resolution, and meanwhile the manufacture difficulty of main magnet, gradient assembly  ...  Magnetic resonance imaging (MRI) is comprehensively applied in modern medical diagnosis and scientific research for its superb soft-tissue imaging quality and non-radiating characteristics.  ...  Hardware of MRI System DOI: http://dx.doi.org/10.5772/intechopen.89132  ... 
doi:10.5772/intechopen.89132 fatcat:ighjupiaxbbbxoa5aaodkpuzla

Fast field-cycling magnetic resonance imaging

David J. Lurie, Silvio Aime, Simona Baroni, Nuala A. Booth, Lionel M. Broche, Chang-Hoon Choi, Gareth R. Davies, Saadiya Ismail, Dara Ó hÓgáin, Kerrin J. Pine
2010 Comptes rendus. Physique  
Nevertheless, FFC-MRI has a number of significant applications and advantages over conventional techniques, and is being pursued in a number of laboratories.  ...  Different approaches to magnet design for FFC-MRI are also described.  ...  As is typical of this type of system, the readout magnet is designed for high homogeneity (as required for MRI), but relatively low field (24 -52 mT).  ... 
doi:10.1016/j.crhy.2010.06.012 fatcat:rwo7y5z22bdildnpdyujci4aoi

Recent Progress in Birdcage RF Coil Technology for MRI System

Sheikh Faisal Ahmad, Young Cheol Kim, Ick Chang Choi, Hyun Deok Kim
2020 Diagnostics  
Among numerous practical designs of RF coils for NMR imaging, the birdcage RF coil is the most popular choice from low field to ultra-high field MRI systems.  ...  This article provides a detailed review of the recent progress in the birdcage RF coil technology for the MRI system.  ...  However, the design of the birdcage coils for ultra-high field MRI applications is a challenging task.  ... 
doi:10.3390/diagnostics10121017 pmid:33261167 pmcid:PMC7759766 fatcat:usgcw3nydbcntdxbciii7idtrm

A Self-Decoupled 32 Channel Receive Array for Human Brain Magnetic Resonance Imaging at 10.5T [article]

Nader Tavaf, Russell L. Lagore, Steve Jungst, Shajan Gunamony, Jerahmie Radder, Andrea Grant, Steen Moeller, Edward Auerbach, Kamil Ugurbil, Gregor Adriany, Pierre-Francois Van de Moortele
2020 arXiv   pre-print
Methods: A self-decoupled 32-channel receive array for human brain imaging at 10.5T (10.5T-32Rx), consisting of 31 loops and one cloverleaf element, was co-designed and built in tandem with a 16-channel  ...  Here, we investigate SNR and parallel imaging gains at 10.5 Tesla (T) compared to 7T using 32-channel receive arrays at both fields.  ...  ACKNOWLEDGMENT The authors acknowledge the constructive feedback of Myung Kyun Woo, Lance DelaBarre, Yigitcan Eryaman, and Matt Waks (all with Center for Magnetic Resonance Research, University of Minnesota  ... 
arXiv:2009.07163v2 fatcat:b6kxnus2ajaklmgipgat25lhfy

Sodium Radiofrequency Coils for Magnetic Resonance: From Design to Applications

Giulio Giovannetti, Alessandra Flori, Nicola Martini, Roberto Francischello, Giovanni Donato Aquaro, Alessandro Pingitore, Francesca Frijia
2021 Electronics  
With the available magnetic fields for clinical MRI scanners (1.5 T, 3 T, 7 T), and the hardware capabilities such as strong gradient strengths with high slew rates and new dedicated radiofrequency (RF  ...  for sodium MRI.  ...  Surface and Volume Dual-Tuned Sodium/Hydrogen Coils The simulation and the design of a dual-tuned sodium/hydrogen surface RF coil for knee MR imaging with an Ultra High Field (UHF) 7 T MRI scanner is described  ... 
doi:10.3390/electronics10151788 fatcat:l3zxu4zbkfho7d4gcmkf2dykvm

Flexible multi-turn multi-gap coaxial RF coils: design concept and implementation for Magnetic Resonance Imaging at 3 and 7 Tesla

Lena Nohava, Raphaela Czerny, Sigrun Roat, Michael Obermann, Andre Kuehne, Roberta Frass-Kriegl, Jacques Felblinger, Jean-Christophe Ginefri, Elmar Laistler
2021 IEEE Transactions on Medical Imaging  
It is demonstrated that this enables free choice of the coil diameter, and thus, optimizing it for the application to a certain anatomical site, while operating at the selfresonance frequency.  ...  Possible configurations regarding size, number of turns and gaps, and cable types for different B0 field strengths are calculated.  ...  The range is almost continuous up to 30 cm in diameter and discontinuities only appear at ultra-high field.  ... 
doi:10.1109/tmi.2021.3051390 pmid:33439836 fatcat:7juhd5drtjblppo7te7gwngx4q

Microwave and RF Heating for Medical Application under Noninvasive Temperature Measurement Using Magnetic Resonance

Yoshio Nikawa, Akira Ishikawa
2010 Journal of the Korean Institute of Electromagnetic Engineering and Science  
RF for heating inside the sample as artificial dielectrics.  ...  The temperature measuring procedure under MR is to measure phase shift of T1, which is the longitudinal relaxation time of proton, for the position inside a sample material with the application of pulsed  ...  going straight forward for ultra high frequency EM wave as X-ray is not available [7] .  ... 
doi:10.5515/jkiees.2010.10.4.244 fatcat:yiv7xiyqbfb2fg7blwvubex6um
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