{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T22:24:28Z","timestamp":1776378268381,"version":"3.51.2"},"reference-count":28,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,3,31]],"date-time":"2024-03-31T00:00:00Z","timestamp":1711843200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the Israel Innovation Authority"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Metamaterial-based designs in ultra-high field (\u22657 T) MRI have the promise of increasing the local magnetic resonance imaging (MRI) signal and potentially even the global efficiency of both the radiofrequency (RF) transmit and receive resonators. A recently proposed metamaterial-like structure\u2014comprised of a high-permittivity dielectric material and a set of evenly distributed copper strips\u2014indeed resulted in a local increase in RF transmission. Here, we demonstrate that non-uniform designs of this metamaterial-like structure can be used to boost the ultimate RF field distribution. A non-uniform dielectric distribution can yield longer electric dipoles, thus extending the RF transmit field coverage. A non-uniform distribution of conducting strips enables the tailoring of the local electric field hot spots, where a concave distribution resulted in lower power deposition. Simulations of the brain and calf regions using our new metamaterial-like design, which combines non-uniform distributions of both the dielectric and conducting strips, revealed a 1.4-fold increase in the RF field coverage compared to the uniform distribution, and a 1.5\u20132-fold increase in the transmit efficiency compared to the standard surface-coil.<\/jats:p>","DOI":"10.3390\/s24072250","type":"journal-article","created":{"date-parts":[[2024,3,31]],"date-time":"2024-03-31T13:32:56Z","timestamp":1711891976000},"page":"2250","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Metamaterial-like Structure Design Using Non-uniformly Distributed Dielectric and Conducting Strips to Boost the RF Field Distribution in 7 T MRI"],"prefix":"10.3390","volume":"24","author":[{"given":"Santosh Kumar","family":"Maurya","sequence":"first","affiliation":[{"name":"Department of Brain Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel"},{"name":"The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot 7610001, Israel"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1580-9964","authenticated-orcid":false,"given":"Rita","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Department of Brain Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel"},{"name":"The Azrieli National Institute for Human Brain Imaging and Research, Weizmann Institute of Science, Rehovot 7610001, Israel"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1263","DOI":"10.1016\/j.mri.2003.08.027","article-title":"Ultrahigh field magnetic resonance imaging and spectroscopy","volume":"21","author":"Adriany","year":"2003","journal-title":"Magn. 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