Premium
Cardiorespiratory motion‐tracking via self‐refocused rosette navigators
Author(s) -
Rigie David,
Vahle Thomas,
Zhao Tiejun,
Czekella Björn,
Frohwein Lynn J.,
Schäfers Klaus,
Boada Fernando E.
Publication year - 2019
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.27609
Subject(s) - imaging phantom , tracking (education) , diaphragm (acoustics) , match moving , computer science , motion (physics) , artificial intelligence , ventricle , signal (programming language) , biomedical engineering , computer vision , nuclear medicine , physics , medicine , acoustics , cardiology , psychology , pedagogy , loudspeaker , programming language
Purpose To develop a flexible method for tracking respiratory and cardiac motions throughout MR and PET‐MR body examinations that requires no additional hardware and minimal sequence modification. Methods The incorporation of a contrast‐neutral rosette navigator module following the RF excitation allows for robust cardiorespiratory motion tracking with minimal impact on the host sequence. Spatial encoding gradients are applied to the FID signal and the desired motion signals are extracted with a blind source separation technique. This approach is validated with an anthropomorphic, PET‐MR‐compatible motion phantom as well as in 13 human subjects. Results Both respiratory and cardiac motions were reliably extracted from the proposed rosette navigator in phantom and patient studies. In the phantom study, the MR‐derived motion signals were additionally validated against the ground truth measurement of diaphragm displacement and left ventricle model triggering pulse. Conclusion The proposed method yields accurate respiratory and cardiac motion‐state tracking, requiring only a short (1.76 ms) additional navigator module, which is self‐refocusing and imposes minimal constraints on sequence design.