Abstract:
:Inhomogeneities in the transmit radio frequency magnetic field ( ) reduce the quality of magnetic resonance (MR) images. This quality can be improved by using high-permittivity pads that tailor the fields. The design of an optimal pad is application-specific and not straightforward and would therefore benefit from a systematic optimization approach. In this paper, we propose such a method to efficiently design dielectric pads. To this end, a projection-based model order reduction technique is used that significantly decreases the dimension of the design problem. Subsequently, the resulting reduced-order model is incorporated in an optimization method in which a desired field in a region of interest can be set. The method is validated by designing a pad for imaging the cerebellum at 7 T. The optimal pad that is found is used in an MR measurement to demonstrate its effectiveness in improving the image quality.
journal_name
IEEE Trans Med Imagingjournal_title
IEEE transactions on medical imagingauthors
van Gemert JHF,Brink WM,Webb AG,Remis RFdoi
10.1109/TMI.2018.2791179subject
Has Abstractpub_date
2018-04-01 00:00:00pages
1035-1044issue
4eissn
0278-0062issn
1558-254Xjournal_volume
37pub_type
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