You can manage bookmarks using lists, please log in to your user account for this.
Media type:
E-Article
Title:
Phase‐contrast acceleration mapping with synchronized encoding
Contributor:
Schmidt, Simon;
Bruschewski, Martin;
Flassbeck, Sebastian;
John, Kristine;
Grundmann, Sven;
Ladd, Mark E.;
Schmitter, Sebastian
Published:
Wiley, 2021
Published in:
Magnetic Resonance in Medicine, 86 (2021) 6, Seite 3201-3210
Language:
English
DOI:
10.1002/mrm.28948
ISSN:
0740-3194;
1522-2594
Origination:
Footnote:
Description:
PurposeTo develop a phase‐contrast (PC) ‐based method for direct and unbiased quantification of the acceleration vector field by synchronization of the spatial and acceleration encoding time points. The proposed method explicitly aims at in‐vitro applications, requiring high measurement accuracy, as well as the validation of clinically relevant acceleration‐encoded sequences.MethodsA velocity‐encoded sequence with synchronized encoding (SYNC SPI) was modified to allow direct acceleration mapping by replacing the bipolar encoding gradients with tripolar gradient waveforms. The proposed method was validated in two in‐vitro flow cases: a rotation and a stenosis phantom. The thereby obtained velocity and acceleration vector fields were quantitatively compared to those acquired with conventional PC methods, as well as to theoretical data.ResultsThe rotation phantom study revealed a systematic bias of the conventional PC acceleration mapping method that resulted in an average pixel‐wise relative angle between the measured and theoretical vector field of (7.8 ± 3.2)°, which was reduced to (−0.4 ± 2.7)° for the proposed SYNC SPI method. Furthermore, flow features in the stenosis phantom were displaced by up to 10 mm in the conventional PC data compared with the acceleration‐encoded SYNC SPI data.ConclusionsThis work successfully demonstrates a highly accurate method for direct acceleration mapping. It thus complements the existing velocity‐encoded SYNC SPI method to enable the direct and unbiased quantification of both the velocity and acceleration vector field for in vitro studies. Hence, this method can be used for the validation of conventional acceleration‐encoded PC methods applicable in‐vivo.