{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,31]],"date-time":"2026-03-31T10:35:18Z","timestamp":1774953318092,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,10,30]],"date-time":"2021-10-30T00:00:00Z","timestamp":1635552000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["U01-EB025144"],"award-info":[{"award-number":["U01-EB025144"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["S10-RR029672"],"award-info":[{"award-number":["S10-RR029672"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["P41-EB015894"],"award-info":[{"award-number":["P41-EB015894"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["P41-EB027061"],"award-info":[{"award-number":["P41-EB027061"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"National Institutes of Health","doi-asserted-by":"publisher","award":["P30-NS076408"],"award-info":[{"award-number":["P30-NS076408"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"name":"BK21 FOUR program of the Education and Research Program for Future ICT Pioneers, Seoul National University","award":["A0426-20210100"],"award-info":[{"award-number":["A0426-20210100"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>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). Previously, we evaluated a 16-channel combined loop + dipole antenna (LD) 10.5 T head array. While the LD array configuration did not achieve the desired B1+ efficiency, it showed an improvement of the specific absorption rate (SAR) efficiency compared to the separate 8-channel loop and separate 8-channel dipole antenna arrays at 10.5 T. Here we compare a 16-channel dipole antenna array with a 16-channel LD array of the same dimensions to evaluate B1+ efficiency, 10 g SAR, and SAR efficiency. The 16-channel dipole antenna array achieved a 24% increase in B1+ efficiency in the electromagnetic simulation and MR experiment compared to the LD array, as measured in the central region of a phantom. Based on the simulation results with a human model, we estimate that a 16-channel dipole antenna array for human brain imaging can increase B1+ efficiency by 15% with similar SAR efficiency compared to a 16-channel LD head array.<\/jats:p>","DOI":"10.3390\/s21217250","type":"journal-article","created":{"date-parts":[[2021,11,1]],"date-time":"2021-11-01T22:24:22Z","timestamp":1635805462000},"page":"7250","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["A 16-Channel Dipole Antenna Array for Human Head Magnetic Resonance Imaging at 10.5 Tesla"],"prefix":"10.3390","volume":"21","author":[{"given":"Myung Kyun","family":"Woo","sequence":"first","affiliation":[{"name":"Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA"},{"name":"Department of Electrical and Computer Engineering, Seoul National University, Gwanak-gu, Seoul 08826, Korea"}]},{"given":"Lance","family":"DelaBarre","sequence":"additional","affiliation":[{"name":"Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA"}]},{"given":"Matt","family":"Waks","sequence":"additional","affiliation":[{"name":"Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA"}]},{"given":"Jerahmie","family":"Radder","sequence":"additional","affiliation":[{"name":"Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA"}]},{"given":"Uk-Su","family":"Choi","sequence":"additional","affiliation":[{"name":"Gwangju Alzheimer\u2019s Disease and Related Dementia Cohort Research Center, Chosun University, Gwangju 61452, Korea"}]},{"given":"Russell","family":"Lagore","sequence":"additional","affiliation":[{"name":"Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA"}]},{"given":"Kamil","family":"Ugurbil","sequence":"additional","affiliation":[{"name":"Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6428-9005","authenticated-orcid":false,"given":"Gregor","family":"Adriany","sequence":"additional","affiliation":[{"name":"Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, MN 55455, USA"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"190","DOI":"10.1038\/242190a0","article-title":"Image formation by induced local interactions: Examples employing nuclear magnetic resonance","volume":"242","author":"Lauterbur","year":"1973","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"L55","DOI":"10.1088\/0022-3719\/10\/3\/004","article-title":"Multi-planar image formation using NMR spin echoes","volume":"10","author":"Mansfield","year":"1977","journal-title":"J. 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