{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T18:51:09Z","timestamp":1774378269682,"version":"3.50.1"},"reference-count":90,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,2,15]],"date-time":"2022-02-15T00:00:00Z","timestamp":1644883200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002631","name":"Gachon University","doi-asserted-by":"publisher","award":["GCU-2018-0673"],"award-info":[{"award-number":["GCU-2018-0673"]}],"id":[{"id":"10.13039\/501100002631","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Ministry of Health and Welfare of the Republic of Korea","award":["HR14C-0002-010014"],"award-info":[{"award-number":["HR14C-0002-010014"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Magnetic resonance imaging (MRI) systems must undergo quantitative evaluation through daily and periodic performance assessments. In general, the reference or standard radiofrequency (RF) coils for these performance assessments of 1.5 to 7.0 T MRI systems have been low-pass-type birdcage (LP-BC) RF coils. However, LP-BC RF coils are inappropriate for use as reference RF coils because of their relatively lower magnetic field (B1-field) sensitivity than other types of BC RF coils, especially in ultrahigh-field (UHF) MRI systems above 3.0 T. Herein, we propose a hybrid-type BC (Hybrid-BC) RF coil as a reference RF coil with improved B1-field sensitivity in UHF MRI system and applied it to an 11.7 T MRI system. An electromagnetic field (EM-field) analysis on the Hybrid-BC RF coil was performed to provide the proper dimensions for its use as a reference RF coil. Commercial finite difference time-domain program was used in EM-field simulation, and home-made analysis programs were used in analysis. The optimal specifications of the proposed Hybrid-BC RF coils for them to qualify as reference RF coils are proposed based on their B1+-field sensitivity under unnormalized conditions, as well as by considering their B1+-field uniformity and RF safety under normalized conditions.<\/jats:p>","DOI":"10.3390\/s22041512","type":"journal-article","created":{"date-parts":[[2022,2,15]],"date-time":"2022-02-15T22:44:47Z","timestamp":1644965087000},"page":"1512","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Preliminary Study for Reference RF Coil at 11.7 T MRI: Based on Electromagnetic Field Simulation of Hybrid-BC RF Coil According to Diameter and Length at 3.0, 7.0 and 11.7 T"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8454-5002","authenticated-orcid":false,"given":"Jeung-Hoon","family":"Seo","sequence":"first","affiliation":[{"name":"Neuroscience Research Institute, Gachon University, Incheon 21988, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7408-8215","authenticated-orcid":false,"given":"Jun-Young","family":"Chung","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, College of Medicine, Gachon University, Incheon 21565, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,15]]},"reference":[{"key":"ref_1","first-page":"622","article-title":"An efficient, highly homogeneous radiofrequency coil for whole-body NMR imaging at 1.5T","volume":"63","author":"Hayes","year":"1985","journal-title":"J. Magn. Reson."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1006\/jmre.1996.7488","article-title":"Resonant modes of the birdcage coil","volume":"124","author":"Leifer","year":"1997","journal-title":"J. Magn. Reson."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.1016\/0730-725X(94)91240-W","article-title":"RF coil optimization: Evaluation of B1 field homogeneity using field histograms and finite element calculations","volume":"12","author":"Li","year":"1994","journal-title":"Magn. Reson. Imaging"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1109\/JERM.2018.2879396","article-title":"RF Aspects of High-Field Magnetic Resonance Imaging (HF-MRI): Recent Advances","volume":"3","author":"Caverly","year":"2019","journal-title":"IEEE J. Electromagn. RF Microw. Med. Biol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"801","DOI":"10.1049\/el.2016.0533","article-title":"Influence of biological subject, shielding cage, and resonance frequency on radio wave propagation in a birdcage coil","volume":"52","author":"Seo","year":"2016","journal-title":"Electron. Lett."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"747","DOI":"10.1002\/sca.21324","article-title":"Multi-port-driven birdcage coil for multiple-mouse MR imaging at 7 T","volume":"38","author":"Heo","year":"2016","journal-title":"Scanning"},{"key":"ref_7","unstructured":"Cheng, T., Magill, A.W., Comment, A., Gruetter, R., and Lei, H. (2014, January 26\u201330). Ultra-high field birdcage coils: A comparison study at 14.1T. Proceedings of the 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS 2014), Chicago, IL, USA."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1097\/RLI.0000000000000820","article-title":"7 Tesla and beyond: Advanced methods and clinical applications in magnetic resonance imaging","volume":"56","author":"Platt","year":"2021","journal-title":"Investig. Radiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"192","DOI":"10.4283\/JMAG.2018.23.2.192","article-title":"Surface coil with an inductively coupled wireless surface and volume coil for improving the magnetic field sensitivity at 400-MHz MRI","volume":"23","author":"Seo","year":"2018","journal-title":"J. Magn."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1002\/nbm.1046","article-title":"An introduction to coil array design for parallel MR","volume":"19","author":"Ohliger","year":"2006","journal-title":"NMR Biomed."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"633","DOI":"10.1002\/1522-2594(200010)44:4<633::AID-MRM18>3.0.CO;2-K","article-title":"Novel quadrature birdcage coil for a vertical B0 field open MRI system","volume":"44","author":"Fujita","year":"2000","journal-title":"Magn. Reson. Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1006\/jmre.2002.2547","article-title":"A double end-cap birdcage RF coil for small animal whole body imaging","volume":"156","author":"Gulsen","year":"2002","journal-title":"J. Magn. Reson."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"653","DOI":"10.1002\/mrm.27350","article-title":"Changes in the specific absorption rate (SAR) of radiofrequency energy in patients with retained cardiac leads during MRI at 1.5 T and 3 T","volume":"81","author":"Golestanirad","year":"2019","journal-title":"Magn. Reson. Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1002\/mrm.22174","article-title":"Experimental and numerical assessment of MRI-induced temperature change and SAR distributions in phantoms and in vivo","volume":"63","author":"Oh","year":"2010","journal-title":"Magn. Reson. Med."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1002\/cmr.b.20012","article-title":"A quadrature lowpass birdcage coil for a vertical low field MRI scanner","volume":"22B","author":"Giovannetti","year":"2004","journal-title":"Concepts Magn. Reson. Part B Magn. Reson. Eng."},{"key":"ref_16","unstructured":"Mispelter, J., Lupu, M., and Briguet, A. (2015). NMR Probeheads for Biophysical and Biomedical Experiments, Imperial College Press. [2nd ed.]."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/j.jmr.2012.05.016","article-title":"A volume birdcage coil with an adjustable sliding tuner ring for neuroimaging in high field vertical magnets: Ex and in vivo applications at 21.1 T","volume":"221","author":"Qian","year":"2012","journal-title":"J. Magn. Reson."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"284","DOI":"10.1002\/(SICI)1522-2594(200002)43:2<284::AID-MRM16>3.0.CO;2-C","article-title":"A transmit-only\/receive-only (TORO) RF system for high-field MRI\/MRS applications","volume":"43","author":"Barberi","year":"2000","journal-title":"Magn. Reson. Med."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Kim, Y.C., Kim, H.D., Yun, B.-J., and Ahmad, S.F. (2020). A simple analytical solution for the designing of the birdcage RF coil used in NMR imaging applications. Appl. Sci., 10.","DOI":"10.3390\/app10072242"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1002\/cmr.b.21260","article-title":"Birdcage coils: Equivalent capacitance and equivalent inductance","volume":"44","author":"Giovannetti","year":"2014","journal-title":"Concepts Magn. Reson."},{"key":"ref_21","unstructured":"Vaughan, J.T., and Griffiths, J.R. (2012). RF Coils for MRI, WILEY."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Puddu, C., Fanti, A., Curreli, N., and Mazzarella, G. (2014, January 10\u201311). Challenging the lumped birdcage coil model for high-field MRI. Proceedings of the IEEE 2014 Loughborough Antennas & Propagation Conference (LAPC), Loughborough, Leicestershire, UK.","DOI":"10.1109\/LAPC.2014.6996383"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1097\/RLI.0000000000000824","article-title":"The clinical utility of magnetic resonance imaging according to field strength, specifically addressing the breadth of current state-of-the-art systems, which include 0.55 T, 1.5 T, 3 T, and 7 T","volume":"57","author":"Runge","year":"2022","journal-title":"Investig. Radiol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1016\/S0730-725X(01)00300-9","article-title":"Dielectric resonances and B1 field inhomogeneity in UHF MRI: Computational analysis and experimental findings","volume":"19","author":"Ibrahim","year":"2001","journal-title":"Magn. Reson. Imaging"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2719","DOI":"10.1088\/0031-9155\/41\/12\/011","article-title":"Computation of electromagnetic fields for high-frequency magnetic resonance imaging applications","volume":"41","author":"Jin","year":"1996","journal-title":"Phys. Med. Biol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"591","DOI":"10.1049\/el.2015.4511","article-title":"B1 propagation properties of combined circularly polarised mode in ultra-high-field MRI","volume":"52","author":"Kim","year":"2016","journal-title":"Electron. Lett."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"308","DOI":"10.4283\/JMAG.2015.20.3.308","article-title":"Design of crisscrossed double-layer birdcage coil for improving B1+ field homogeneity for small-animal magnetic resonance imaging at 300 MHz","volume":"20","author":"Seo","year":"2015","journal-title":"J. Magn."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"147","DOI":"10.3103\/S1541308X17020121","article-title":"Helmholtz transceiver array for improving the |B1|-field homogeneity at 7-T magnetic resonance imaging","volume":"25","author":"Seo","year":"2017","journal-title":"Phys. Wave Phen."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.jmr.2017.12.011","article-title":"B1-control receive array coil (B-RAC) for reducing B1+ inhomogeneity in abdominal imaging at 3T-MRI","volume":"287","author":"Kaneko","year":"2018","journal-title":"J. Magn. Reson."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1007\/s10334-018-0693-9","article-title":"Improvement of 19F MR image uniformity in a mouse model of cellular therapy using inductive coupling","volume":"32","author":"Park","year":"2019","journal-title":"Magn. Reson. Mater. Phys. Biol. Med."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2343","DOI":"10.1002\/mrm.27880","article-title":"Cardiorenal sodium MRI at 7.0 Tesla using a 4\/4 channel 1H\/23Na radiofrequency antenna array","volume":"82","author":"Boehmert","year":"2019","journal-title":"Magn. Reson. Med."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"3826","DOI":"10.1002\/mrm.27688","article-title":"A numerical and experimental study of RF shimming in the presence of hip prostheses using adaptive SAR at 3 T","volume":"81","author":"Destruel","year":"2019","journal-title":"Magn. Reson. Med."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e4039","DOI":"10.1002\/nbm.4039","article-title":"Homogeneous B1+ for bilateral breast imaging at 7 T using a five dipole transmit array merged with a high density receive loop array","volume":"32","author":"Krikken","year":"2019","journal-title":"NMR Biomed."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Kim, K.N., Hernandez, D., Seo, J.H., Noh, Y., Han, Y., Ryu, Y.C., and Chung, J.Y. (2019). Quantitative assessment of phased array coils with different numbers of receiving channels in terms of signal-to-noise ratio and spatial noise variation in magnetic resonance imaging. PLoS ONE, 14.","DOI":"10.1371\/journal.pone.0219407"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"725","DOI":"10.1007\/s10334-020-00827-7","article-title":"Sensitivity and uniformity improvement of phased array MR images using inductive coupling and RF detuning circuits","volume":"33","author":"Park","year":"2020","journal-title":"Magn. Reson. Mater. Phys. Biol. Med."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1016\/j.jmr.2019.07.004","article-title":"Design of a novel antisymmetric coil array for parallel transmit cardiac MRI in pigs at 7 T","volume":"305","author":"Elabyad","year":"2019","journal-title":"J. Magn. Reson."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"3373","DOI":"10.1002\/mrm.28915","article-title":"An asymmetrical whole-body birdcage RF coil without RF shield for hyperpolarized (129) Xe lung MR imaging at 1.5 T","volume":"86","author":"Puddu","year":"2021","journal-title":"Magn. Reson. Med."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"e3860","DOI":"10.1002\/nbm.3860","article-title":"Radial magnetic resonance imaging (MRI) using a rotating radiofrequency (RF) coil at 9.4 T","volume":"31","author":"Li","year":"2018","journal-title":"NMR Biomed."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"253","DOI":"10.2463\/mrms.tn.2016-0149","article-title":"An asymmetric birdcage coil for small-animal MR imaging at 7T","volume":"16","author":"Kim","year":"2017","journal-title":"Magn. Reson. Med. Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"106774","DOI":"10.1016\/j.jmr.2020.106774","article-title":"Design of a RF-resonant set improving locally the B1+ efficiency. Applications for clinical MRI in andrology and urology","volume":"317","author":"Koreshin","year":"2020","journal-title":"J. Magn. Reson."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"2978","DOI":"10.1002\/mp.12931","article-title":"7T ultra-high field body MR imaging with an 8-channel transmit\/32-channel receive radiofrequency coil array","volume":"45","author":"Rietsch","year":"2018","journal-title":"Med. Phys."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1002\/sca.21217","article-title":"Development of double-layer coupled coil for improving S\/N in 7 T small-animal MRI","volume":"37","author":"Kim","year":"2015","journal-title":"Scanning."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"898","DOI":"10.1049\/el.2016.0638","article-title":"Improvements in magnetic field intensity and uniformity for small-animal MRI through a high-permittivity material attachment","volume":"52","author":"Seo","year":"2016","journal-title":"Electron. Lett."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"515","DOI":"10.1002\/sca.21290","article-title":"Magnetic field sensitivity at 7-T using dual-helmholtz transmit-only coil and 12-channel receive-only bended coil","volume":"38","author":"Kim","year":"2016","journal-title":"Scanning"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1002\/jmri.23988","article-title":"Radiofrequency field enhancement with high dielectric constant (HDC) pads in a receive array coil at 3.0T","volume":"38","author":"Yang","year":"2013","journal-title":"J. Magn. Reson. Imaging"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1088\/0031-9155\/46\/2\/324","article-title":"B1 field homogeneity and SAR calculations for the birdcage coil","volume":"46","author":"Ibrahim","year":"2001","journal-title":"Phys. Med. Biol."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"1305","DOI":"10.1002\/mrm.22724","article-title":"Reduction of implant RF heating through modification of transmit coil electric field","volume":"65","author":"Eryaman","year":"2011","journal-title":"Magn. Reson. Med."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1157","DOI":"10.1002\/mrm.24329","article-title":"SAR simulations for high-field MRI: How much detail, effort, and accuracy is needed?","volume":"69","author":"Wolf","year":"2013","journal-title":"Magn. Reson. Med."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"615","DOI":"10.1002\/mrm.27379","article-title":"Adaptive SAR mass-averaging framework to improve predictions of local RF heating near a hip implant for parallel transmit at 7 T","volume":"81","author":"Destruel","year":"2019","journal-title":"Magn. Reson. Med."},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Krishnamurthy, N., Santini, T., Wood, S., Kim, J., Zhao, T., Aizenstein, H.J., and Ibrahim, T.S. (2019). Computational and experimental evaluation of the Tic-Tac-Toe RF coil for 7 Tesla MRI. PLoS ONE, 14.","DOI":"10.1371\/journal.pone.0209663"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/j.neuroimage.2019.05.015","article-title":"Reconfigurable MRI technology for low-SAR imaging of deep brain stimulation at 3T: Application in bilateral leads, fully-implanted systems, and surgically modified lead trajectories","volume":"199","author":"Kazemivalipour","year":"2019","journal-title":"Neuroimage"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"219","DOI":"10.1016\/j.ejmp.2021.02.008","article-title":"Electromagnetic simulation of RF burn injuries occurring at skin-skin and skin-bore wall contact points in an MRI scanner with a birdcage coil","volume":"82","author":"Tang","year":"2021","journal-title":"Phys. Med."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1178","DOI":"10.1109\/TBME.2020.3022884","article-title":"Metamaterial-inspired radiofrequency (RF) shield with reduced specific absorption rate (SAR) and improved transmit efficiency for UHF MRI","volume":"68","author":"Chen","year":"2021","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"2290","DOI":"10.1002\/mrm.28845","article-title":"Open birdcage coil for head imaging at 7T","volume":"86","author":"Nikulin","year":"2021","journal-title":"Magn. Reson. Med."},{"key":"ref_55","first-page":"e4656","article-title":"Performance and safety assessment of an integrated transmit array for body imaging at 7 T under consideration of specific absorption rate, tissue temperature, and thermal dose","volume":"28","author":"Fiedler","year":"2021","journal-title":"NMR Biomed."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"1299","DOI":"10.1002\/mrm.28784","article-title":"Specific absorption rate and temperature in neonate models resulting from exposure to a 7T head coil","volume":"86","author":"Malik","year":"2021","journal-title":"Magn. Reson. Med."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"1822","DOI":"10.3938\/jkps.66.1822","article-title":"Investigation of the B1 field distribution and RF power deposition in a birdcage coil as functions of the number of coil legs at 4.7 T, 7.0 T, and 11.7 T","volume":"66","author":"Seo","year":"2015","journal-title":"J. Korean Phys. Soc."},{"key":"ref_58","first-page":"302","article-title":"Numerical solution of initial boundary value problems involving Maxwell\u2019s equations in isotropic media","volume":"14","author":"Yee","year":"1996","journal-title":"IEEE Trans. Antennas Propag."},{"key":"ref_59","unstructured":"Hasgall, P.A., Di Gennaro, F., Baumgartner, C., Neufeld, E., Lloyd, B., Gosselin, M.C., Payne, D., Klingenb\u00f6ck, A., and Kuster, N. (2018). IT\u2019IS Database for Thermal and Electromagnetic Parameters of Biological Tissues, IT\u2019IS Foundation. Version 4.0."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1002\/1099-0534(2000)12:4<173::AID-CMR1>3.0.CO;2-Q","article-title":"The principle of reciprocity in signal strength calculations\u2014A mathematical guide","volume":"12","author":"Hoult","year":"2000","journal-title":"Concepts Magn. Reson."},{"key":"ref_61","doi-asserted-by":"crossref","unstructured":"Herrmann, T., Liebig, T., Mallow, J., Bruns, C., Stadler, J., Mylius, J., Brosch, M., Svedja, J.T., Chen, Z., and Rennings, A. (2018). Metamaterial-based transmit and receive system for whole-body magnetic resonance imaging at ultra-high magnetic fields. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0191719"},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1002\/cmr.b.20185","article-title":"Studies of RF shimming techniques with minimization of RF power deposition and their associated temperature changes","volume":"39B","author":"Tang","year":"2011","journal-title":"Concepts Magn. Reson. Part B Magn. Reson. Eng."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1002\/mrm.21729","article-title":"A phase-sensitive method of flip angle mapping","volume":"60","author":"Morrell","year":"2008","journal-title":"Magn. Reson. Med."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"1470","DOI":"10.1002\/mrm.22845","article-title":"Calculation of radiofrequency electromagnetic fields and their effects in MRI of human subjects","volume":"65","author":"Collins","year":"2011","journal-title":"Magn. Reson. Med."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1109\/JERM.2019.2913111","article-title":"Impact of electrode structure on RF-induced heating for an AIMD implanted lead in a 1.5-Tesla MRI system","volume":"3","author":"Yang","year":"2019","journal-title":"IEEE J. Electromagn. RF Microw. Med. Biol."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"383","DOI":"10.1002\/mrm.26344","article-title":"Potential for high-permittivity materials to reduce local SAR at a pacemaker lead tip during MRI of the head with a body transmit coil at 3\u2009T","volume":"78","author":"Yu","year":"2016","journal-title":"Magn. Reson. Med."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"362","DOI":"10.1002\/mrm.10197","article-title":"Polarization of the RF field in a human head at high field: A study with a quadrature surface coil at 7.0 T","volume":"48","author":"Wang","year":"2002","journal-title":"Magn. Reson. Med."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"675509","DOI":"10.3389\/fphy.2021.675509","article-title":"Dipole-fed rectangular dielectric resonator antennas for magnetic resonance imaging at 7 T: The impact of quasi-transverse electric modes on transmit field distribution","volume":"9","author":"Wenz","year":"2021","journal-title":"Front. Phys."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"296","DOI":"10.1016\/j.neuroimage.2017.04.053","article-title":"Analysis strategies for high-resolution UHF-fMRI data","volume":"168","author":"Polimeni","year":"2018","journal-title":"NeuroImage"},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1007\/s00234-020-02629-z","article-title":"Clinical 7-T MRI for neuroradiology: Strengths, weaknesses, and ongoing challenges","volume":"63","author":"Burkett","year":"2021","journal-title":"Neuroradiology"},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.pnmrs.2018.06.001","article-title":"Pros and cons of ultra-high-field MRI\/MRS for human application","volume":"109","author":"Ladd","year":"2018","journal-title":"Prog. Nucl. Magn. Reson. Spectrosc."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1186\/s41747-021-00216-2","article-title":"MRI with ultrahigh field strength and high-performance gradients: Challenges and opportunities for clinical neuroimaging at 7 T and beyond","volume":"5","author":"Vachha","year":"2021","journal-title":"Eur. Radiol. Exp."},{"key":"ref_73","doi-asserted-by":"crossref","unstructured":"Terekhov, M., Elabyad, I.A., and Schreiber, L.M. (2021). Global optimization of default phases for parallel transmit coils for ultra-high-field cardiac MRI. PLoS ONE, 16.","DOI":"10.1371\/journal.pone.0255341"},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"3292","DOI":"10.1002\/mrm.28923","article-title":"Displacement current distribution on a high dielectric constant helmet and its effect on RF field at 10.5 T (447 MHz)","volume":"86","author":"Gandji","year":"2021","journal-title":"Magn. Reson. Med."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1109\/TASC.2020.2983702","article-title":"Commissioning completion of the iseult whole body 11.7 T MRI system. IEEE Trans","volume":"30","author":"Quettier","year":"2020","journal-title":"Appl. Supercond."},{"key":"ref_76","doi-asserted-by":"crossref","unstructured":"Ahmad, S.F., Kim, Y.C., Choi, I.C., and Kim, H.D. (2020). Recent progress in birdcage RF coil technology for MRI system. Diagnostics, 10.","DOI":"10.3390\/diagnostics10121017"},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"1734","DOI":"10.1002\/mrm.28772","article-title":"Combined 23Na and 13C imaging at 3.0 Tesla using a single-tuned large FOV birdcage coil","volume":"86","author":"Kaggie","year":"2021","journal-title":"Magn. Reson. Med."},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"e4204","DOI":"10.1002\/nbm.4204","article-title":"Feasibility of 31P spectroscopic imaging at 7 T in lung carcinoma patients","volume":"34","author":"Verhoeff","year":"2021","journal-title":"NMR Biomed."},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"2015","DOI":"10.1109\/TMI.2021.3070626","article-title":"Design and construction of a PET-compatible double-tuned 1H\/31P MR head coil","volume":"40","author":"Celik","year":"2021","journal-title":"IEEE Trans. Med. Imaging"},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1016\/j.mri.2019.11.018","article-title":"Rapid four-ring birdcage coil analysis: Design optimization for high efficiency, low interference, and improved body loading tolerance","volume":"66","author":"Shan","year":"2020","journal-title":"Magn. Reson. Imaging"},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"53","DOI":"10.3389\/fnhum.2020.00053","article-title":"MRI-induced heating of coils for microscopic magnetic stimulation at 1.5 Tesla: An initial study","volume":"14","author":"Bonmassar","year":"2020","journal-title":"Front Hum. Neurosci."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/j.jmr.2017.12.003","article-title":"Design and use of a folded four-ring double-tuned birdcage coil for rat brain sodium imaging at 9.4 T","volume":"286","author":"Ha","year":"2018","journal-title":"J. Magn. Reson."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"40","DOI":"10.1002\/bem.22382","article-title":"Proton\/deuterium magnetic resonance imaging of rodents at 9.4T using birdcage coils","volume":"43","author":"Zhang","year":"2022","journal-title":"Bioelectromagnetics"},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"2102469","DOI":"10.1002\/adma.202102469","article-title":"Adaptive cylindrical wireless metasurfaces in clinical magnetic resonance imaging","volume":"33","author":"Chi","year":"2021","journal-title":"Adv. Mater."},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1016\/j.mri.2021.03.012","article-title":"Optimization of a quadrature birdcage coil for functional imaging of squirrel monkey brain at 9.4T","volume":"79","author":"Lu","year":"2021","journal-title":"Magn. Reson. Imaging"},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"107023","DOI":"10.1016\/j.jmr.2021.107023","article-title":"A broad tuneable birdcage coil for mouse 1H\/19F MR applications","volume":"329","author":"Buriana","year":"2021","journal-title":"J. Magn. Reson."},{"key":"ref_87","doi-asserted-by":"crossref","unstructured":"Giovannetti, G., Flori, A., Santarelli, M.F., Positano, V., Martini, N., Francischello, R., Schulte, R.F., Ardenkjaer-Larsen, J.H., Menichetti, L., and Aquaro, G.D. (2021). Radio frequency coils for hyperpolarized 13C magnetic resonance experiments with a 3T MR clinical scanner: Experience from a cardiovascular Lab. Electronics, 10.","DOI":"10.3390\/electronics10040366"},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"817","DOI":"10.1016\/j.acra.2020.04.025","article-title":"Reproducibility of hyperpolarized 129Xe MRI ventilation defect percent in severe asthma to evaluate clinical trial feasibility","volume":"28","author":"Svenningsen","year":"2021","journal-title":"Acad. Radiol."},{"key":"ref_89","doi-asserted-by":"crossref","unstructured":"Valkovi\u010d, L., Dragonu, I., Almujayyaz, S., Batzakis, A., Young, L.A.J., Purvis, L.A.B., Clarke, W.T., Wichmann, T., Lanz, T., and Neubauer, S. (2017). Using a whole-body 31P birdcage transmit coil and 16-element receive array for human cardiac metabolic imaging at 7T. PLoS ONE, 12.","DOI":"10.1371\/journal.pone.0187153"},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"1512","DOI":"10.1002\/mrm.28005","article-title":"A dual-tuned 17O\/1H head array for direct brain oximetry at 3 Tesla","volume":"83","author":"Lakshmanan","year":"2020","journal-title":"Magn. Reson. Med."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/4\/1512\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T22:20:12Z","timestamp":1760134812000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/4\/1512"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,2,15]]},"references-count":90,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2022,2]]}},"alternative-id":["s22041512"],"URL":"https:\/\/doi.org\/10.3390\/s22041512","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,2,15]]}}}