Predicting temperature increase through local SAR estimation by B1 mapping: A phantom validation at 7T

Author

Xiaotong Zhang ; Jiaen Liu ; Schmitter, Sebastian ; Van de Moortele, Pierre-Francois ; Bin He

Author_Institution

Dept. of Biomed. Eng., Univ. of Minnesota, Minneapolis, MN, USA

fYear

2014

fDate

26-30 Aug. 2014

Firstpage

1107

Lastpage

1110

Abstract

It has been shown that Electrical Properties d(EPs) of biological tissues can be derived from MR-based B1 measurement. A strong appeal for these `Electrical Property Tomography´ (EPT) methods is to estimate real-time and subject-specific local specific absorption rate (SAR) induced by RF transmission. In order to investigate the feasibility of EPT-based local SAR estimation, following previously proposed EPT protocols, induced local SAR has been firstly estimated under one B1 shim setting for a heating sequence at 7T; whereas with the same acquired B1 information, induced local SAR under a different B1 shim setting has been further predicted. Both of the SAR results have been compared to measured temperature changes using MRI Thermometry based on the proton chemical shift.

Keywords

bioelectric phenomena; biological tissues; biomedical MRI; biothermics; heating; phantoms; temperature measurement; EPT-based local SAR estimation; MR-based B1 measurement; MRI thermometry; biological tissues; electrical property tomography methods; heating sequence; magnetic flux density 7 T; phantom validation; proton chemical shift; radiofrequencytransmission; real-time SAR estimation; specific absorption rate; subject-specific local SAR estimation; temperature change measurement; Coils; Estimation; Heating; Magnetic resonance imaging; Radio frequency; Temperature measurement;

fLanguage

English

Publisher

ieee

Conference_Titel

Engineering in Medicine and Biology Society (EMBC), 2014 36th Annual International Conference of the IEEE

Conference_Location

Chicago, IL

ISSN

1557-170X

Type

conf

DOI

10.1109/EMBC.2014.6943788

Filename

6943788