Title :
MRI-based temperature and SAR mapping with a new dual-coil solenoid/birdcage heating/measurement system
Author :
Oh, Sukhoon ; Roopnariane, Colin A. ; Tofighi, Mohammad-Reza ; Collins, Christopher M.
Author_Institution :
Coll. of Med., Pennsylvania State Univ., Hershey, PA, USA
Abstract :
We describe an MRI-based method for mapping temperature and specific absorption rate (SAR) using a solenoid coil and a birdcage coil for heating and imaging of a weakly conductive dielectric sample, respectively. The accuracy and the quality of SAR/temperature mapping are enhanced by separating the heating and imaging RF coils. 50 W of RF power is applied to the solenoid coil to heat the conductive agar-gel phantom for 120 sec. Maps of temperature increase were acquired with an MRI-based method. The MR-based measurements were in good agreement with fiber optic measurements. Finally, the dual-coil heating system was simulated using the finite difference time domain (FDTD) method. The distribution of numerically-calculated and experimentally-acquired SAR were also in good agreement.
Keywords :
biological effects of radiation; biomedical MRI; biomedical measurement; finite difference time-domain analysis; phantoms; solenoids; temperature measurement; MRI-based temperature; birdcage coil; conductive agar-gel phantom; dual-coil heating system; dual-coil solenoid; finite difference time domain method; imaging RF coils; specific absorption rate mapping; weakly conductive dielectric sample; Coils; Dielectric measurements; Finite difference methods; Heating; Imaging phantoms; Optical imaging; Radio frequency; Solenoids; Specific absorption rate; Temperature; Biological effects of electromagnetic radiation; Electromagnetic heating; FDTD methods; Magnetic resonance imaging; Temperature measurement;
Conference_Titel :
Radio and Wireless Symposium (RWS), 2010 IEEE
Conference_Location :
New Orleans, LA
Print_ISBN :
978-1-4244-4725-1
Electronic_ISBN :
978-1-4244-4726-8
DOI :
10.1109/RWS.2010.5434270
