Christoph Stefan Aigner1, Sebastian Dietrich1, Tobias Schaeffter1,2, and Sebastian Schmitter1,3
1Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany, 2Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom, 3Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
1Physikalisch-Technische Bundesanstalt (PTB), Braunschweig and Berlin, Germany, 2Division of Imaging Sciences and Biomedical Engineering, King's College London, London, United Kingdom, 3Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
This in-vivo study demonstrates that respiration-resolved
B1+ maps and respiration-robust 4kT pTx pulses are highly preferred to achieve
3D heart FA homogenization at 7T when subjects perform strong breathing.
Figure 4: Evaluation
of four different pulses optimized for the heart ROI on exhale, intermediate,
inhale and optimized on all respiration states (respiration robust) for deep
breathing of all 10 subjects. Depicted are boxplots containing the CVs of all
respiration states. The respiration robust pulse performs best across all subjects
and respiration states with the lowest median and spread.
Figure 5:
Side-by-side comparison of B1+ predictions (a) and reconstructed 3D GRE images
(b) with the 4 kT-points pTx pulses optimized on inhale (left) and respiration
robust (right) of subject 7. Depicted are the views of the acquired 3D volume
close to the position of the B1+ prediction. The arrows point to signal
drop-out regions in using the inhale pulse which are corrected by the
respiration robust pulse.
