Florian
Maier1, Axel Joachim Krafft1, Jrgen W. Jenne2,3,
Rdiger Dillmann4, Wolfhard Semmler1, Michael Bock1
1Medical Physics in Radiology, German
Cancer Research Center (DKFZ), Heidelberg, Germany; 2Clinical
Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ),
Heidelberg, Germany; 3Mediri GmbH, Heidelberg, Germany; 4Institute
of Anthropomatics, Karlsruhe Institute of Technology, Karlsruhe, Germany
Proton
resonance frequency shift thermometry is sensitive to motion. Artifacts are
caused by tissue displacement and susceptibility changes. In this work, a
novel navigator technique for triggering MR thermometry image acquisition is
presented. Non-velocity and velocity encoded navigator signals were acquired
without lengthening of TR. Based on the phase variation of non-encoded values
and the estimated velocity, trigger events were generated. The measurements
indicate that the proposed triggered segmented EPI pulse sequence allows for
motion compensated thermometry of periodically moving tissue.