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Magnetic Resonance Materials in Physics, Biology and Medicine
Erschienen in: Magnetic Resonance Materials in Physics, Biology and Medicine 4/2015

01.08.2015 | Research Article

Single-channel, box-shaped, monopole-type antenna for B1+ field manipulation in conjunction with the traveling-wave concept in 9.4 T MRI

verfasst von: Irena Zivkovic, Klaus Scheffler

Erschienen in: Magnetic Resonance Materials in Physics, Biology and Medicine | Ausgabe 4/2015

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Abstract

Object

We have developed a single-channel, box-shaped, monopole-type antenna which, if used in two different configurations, excites complementary B1+ field distributions in the traveling-wave setup.

Materials and methods

A new monopole-type, single-channel antenna for RF excitation in 9.4 T magnetic resonance imaging is proposed. The antenna is entirely made of copper without lumped elements. Two complementary B1+ field distributions of two different antenna configurations were measured and combined as a root sum of squares. B1+ field inhomogeneity of the combined maps was calculated and compared with published results.

Results

By combining B1+ field distributions generated by two antenna configurations, a “no voids” pattern was achieved for the entire upper brain. B1+ inhomogeneity of approximately 20 % was achieved for sagittal and transverse slices; it was <24 % for coronal slices. The results were comparable with those from CP, with “no voids” in slice B1+ inhomogeneity of multichannel loop arrays. The efficiency of the proposed antenna was lower than that of a multichannel array but comparable with that of a patch antenna.

Conclusion

The proposed single-channel antenna is a promising candidate for traveling-wave brain imaging. It can be combined with the time-interleaved acquisition of modes (TIAMO) concept if reconfigurability is obtained with a single-antenna element.
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Metadaten
Titel
Single-channel, box-shaped, monopole-type antenna for B1+ field manipulation in conjunction with the traveling-wave concept in 9.4 T MRI
verfasst von
Irena Zivkovic
Klaus Scheffler
Publikationsdatum
01.08.2015
Verlag
Springer Berlin Heidelberg
Erschienen in
Magnetic Resonance Materials in Physics, Biology and Medicine / Ausgabe 4/2015
Print ISSN: 0968-5243
Elektronische ISSN: 1352-8661
DOI
https://doi.org/10.1007/s10334-014-0473-0

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