Free-Breathing and Ungated Dynamic MRI Using Navigator-Less Spiral SToRM

IEEE Trans Med Imaging. 2020 Dec;39(12):3933-3943. doi: 10.1109/TMI.2020.3008329. Epub 2020 Nov 30.

Abstract

We introduce a kernel low-rank algorithm to recover free-breathing and ungated dynamic MRI from spiral acquisitions without explicit k-space navigators. It is often challenging for low-rank methods to recover free-breathing and ungated images from undersampled measurements; extensive cardiac and respiratory motion often results in the Casorati matrix not being sufficiently low-rank. Therefore, we exploit the non-linear structure of the dynamic data, which gives the low-rank kernel matrix. Unlike prior work that rely on navigators to estimate the manifold structure, we propose a kernel low-rank matrix completion method to directly fill in the missing k-space data from variable density spiral acquisitions. We validate the proposed scheme using simulated data and in-vivo data. Our results show that the proposed scheme provides improved reconstructions compared to the classical methods such as low-rank and XD-GRASP. The comparison with breath-held cine data shows that the quantitative metrics agree, whereas the image quality is marginally lower.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Algorithms
  • Artifacts
  • Breath Holding
  • Heart / diagnostic imaging
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging*
  • Magnetic Resonance Imaging, Cine
  • Respiration*