Abstract：
:A capacitive impedance metasurface combined with a transceiver coil to improve the radio frequency magnetic field for 1.5T magnetic resonance imaging applications is presented. The novel transceiver provides localized enhancement in magnetic flux density when compared to a transceiver coil alone by incorporating an electrically small metasurface using an interdigital capacitance approach. Full field simulations employing the metasurface show a significant improvement in magnetic flux density inside a homogeneous dielectric phantom, which is also shown to perform well for a range of depths into the phantom. The concept was experimentally demonstrated through vector network analyzer measurements and images have been taken using a 1.5T MRI scanner. The results show there is a 216% improvement in transmission efficiency, a 133% improvement in receiver signal-to-noise-ratio (SNR), and a 415% improvement in transceiver SNR for a particular transmission power when compared against a surface coil positioned at the same distance from the phantom, where these improvements are the maximum observed during experiments.
journal_name
IEEE Trans Med Imagingjournal_title
IEEE transactions on medical imagingauthors
Issa I,Ford KL,Rao M,Wild JMdoi
10.1109/TMI.2019.2942194subject
Has Abstractpub_date
2020-04-01 00:00:00pages
1085-1093issue
4eissn
0278-0062issn
1558-254Xjournal_volume
39pub_type
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