Dataset Information

Fast Fourier-based simulation of off-resonance artifacts in steady-state gradient echo MRI applied to metal object localization.

ABSTRACT:

Purpose

To accelerate simulation of off-resonance artifacts in steady-state gradient echo MRI by using fast Fourier transforms and demonstrate its applicability to metal object localization.

Theory and methods

By exploiting the repetitive nature of steady-state pulse sequences it is possible to use fast Fourier transforms to calculate the MR signal. Based on this principle, a method for fast simulation of off-resonance artifacts was designed. The method was validated against Bloch simulations and MRI scans. Its clinical relevance was demonstrated by employing it for template matching-based metal object localization, as applied to a titanium cylinder, an oxidized zirconium knee implant, and gold fiducials.

Results

The fast simulations were accurate compared with actual MRI scans of the objects. The differences between the fast simulations and Bloch simulations were minor, while the acceleration scaled linearly with the number of phase-encoding lines. The object localization method accurately localized the various metal objects.

Conclusion

The proposed simulation methodology provided accurate 3D simulations of off-resonance artifacts with a lower computational complexity than Bloch simulations. The speed of the simulations opens up possibilities in image reconstructions involving off-resonance phenomena that were previously infeasible due to computational limitations, as demonstrated for metal object localization. Magn Reson Med 78:2035-2041, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

SUBMITTER: Zijlstra F

PROVIDER: S-EPMC5655717 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Fast Fourier-based simulation of off-resonance artifacts in steady-state gradient echo MRI applied to metal object localization.

Zijlstra Frank F Bouwman Job G JG Braškutė Ieva I Viergever Max A MA Seevinck Peter R PR

Magnetic resonance in medicine 20161207 5

<h4>Purpose</h4>To accelerate simulation of off-resonance artifacts in steady-state gradient echo MRI by using fast Fourier transforms and demonstrate its applicability to metal object localization.<h4>Theory and methods</h4>By exploiting the repetitive nature of steady-state pulse sequences it is possible to use fast Fourier transforms to calculate the MR signal. Based on this principle, a method for fast simulation of off-resonance artifacts was designed. The method was validated against Bloch ...[more]

PMID: 27928834

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Dataset Information

Fast Fourier-based simulation of off-resonance artifacts in steady-state gradient echo MRI applied to metal object localization.

Purpose

Theory and methods

Results

Conclusion

Publications

Fast Fourier-based simulation of off-resonance artifacts in steady-state gradient echo MRI applied to metal object localization.

Similar Datasets

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