Morphology-adaptive total variation for the reconstruction of quantitative susceptibility map from the magnetic resonance imaging phase

PLoS One. 2018 May 8;13(5):e0196922. doi: 10.1371/journal.pone.0196922. eCollection 2018.

Abstract

Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging technique that quantifies the magnetic susceptibility distribution within biological tissues. QSM calculates the underlying magnetic susceptibility by deconvolving the tissue magnetic field map with a unit dipole kernel. However, this deconvolution problem is ill-posed. The morphology enabled dipole inversion (MEDI) introduces total variation (TV) to regularize the susceptibility reconstruction. However, MEDI results still contain artifacts near tissue boundaries because MEDI only imposes TV constraint on voxels inside smooth regions. We introduce a Morphology-Adaptive TV (MATV) for improving TV-regularized QSM. The MATV method first classifies imaging target into smooth and nonsmooth regions by thresholding magnitude gradients. In the dipole inversion for QSM, the TV regularization weights are a monotonically decreasing function of magnitude gradients. Thus, voxels inside smooth regions are assigned with larger weights than those in nonsmooth regions. Using phantom and in vivo datasets, we compared the performance of MATV with that of MEDI. MATV results had better visual quality than MEDI results, especially near tissue boundaries. Preliminary brain imaging results illustrated that MATV has potential to improve the reconstruction of regions near tissue boundaries.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Brain / anatomy & histology
  • Brain / diagnostic imaging*
  • Brain Mapping / methods*
  • Humans
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging / methods*
  • Neuroimaging / methods*
  • Phantoms, Imaging

Grants and funding

This research was funded by the National Natural Science Funds of China [61671228 and 61728107, http://www.nsfc.gov.cn/] and the Guangdong Provincial Science & Technology Program [2017B090912006, http://pro.gdstc.gov.cn/egrantweb/] to YF. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.