Accelerated Motion-Aware MR Imaging via Motion Prediction from K-Space Center

Christoph Jud; Damien Nguyen; Alina Giger; Robin Sandkühler; Miriam Krieger; Tony Lomax; Rares Salomir; Oliver Bieri; Philippe C. Cattin

arXiv · 1908.09560

Accelerated Motion-Aware MR Imaging via Motion Prediction from K-Space Center

Christoph Jud·Damien Nguyen·Alina Giger·Robin Sandkühler·Miriam Krieger·Tony Lomax·Rares Salomir·Oliver Bieri·Philippe C. Cattin

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Abstract

Motion has been a challenge for magnetic resonance (MR) imaging ever since the MR has been invented. Especially in volumetric imaging of thoracic and abdominal organs, motion-awareness is essential for reducing motion artifacts in the final image. A recently proposed MR imaging approach copes with motion by observing the motion patterns during the acquisition. Repetitive scanning of the k-space center region enables the extraction of the patient motion while acquiring the remaining part of the k-space. Due to highly redundant measurements of the center, the required scanning time of over 11 min and the reconstruction time of 2 h exceed clinical applicability though. We propose an accelerated motion-aware MR imaging method where the motion is inferred from small-sized k-space center patches and an initial training phase during which the characteristic movements are modeled. Thereby, acquisition times are reduced by a factor of almost 2 and reconstruction times by two orders of magnitude. Moreover, we improve the existing motion-aware approach with a systematic temporal shift correction to achieve a sharper image reconstruction. We tested our method on 12 volunteers and scanned their lungs and abdomen under free breathing. We achieved equivalent to higher reconstruction quality using the motion-prediction compared to the slower existing approach.

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Christoph Jud, Damien Nguyen, Alina Giger, Robin Sandkühler, Miriam Krieger, Tony Lomax, Rares Salomir, Oliver Bieri, Philippe C. Cattin. 2019-08-26. Accelerated Motion-Aware MR Imaging via Motion Prediction from K-Space Center. https://arxiv.org/abs/1908.09560

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