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The effects of molecular diffusion in spatially encoded magnetic resonance imaging

Sina Marhabaie1, Geoffrey Bodenhausen2, Philippe Pelupessy1

  • 1Département de Chimie, École Normale Supérieure, PSL Research University, UPMC Univ Paris 06, CNRS, Laboratoire des Biomolecules (LBM), 24 rue Lhomond, 75005 Paris, France; Sorbonne Universités, UPMC Univ. Paris 06, École Normale Supérieure, CNRS, Laboratoire des Biomolecules (LBM), Paris, France.

Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|November 9, 2016
PubMed

Insights

Diffusion effects can reduce image quality in spatially encoded MRI. This study shows how to adapt MRI sequences to achieve uniformly diffusion-weighted images, improving spatial encoding in challenging magnetic fields.

Area of Science:

  • Magnetic Resonance Imaging (MRI)
  • Image Processing
  • Diffusion MRI

Background:

  • Spatially encoded MRI improves image quality, especially in inhomogeneous fields.
  • Traditional k-space encoding has limitations in certain MRI scenarios.
  • Previous research focused on homogenizing T2 losses in MRI.

Purpose of the Study:

  • To investigate the impact of diffusion on image quality in spatially encoded MRI.
  • To identify non-uniformities in diffusion-related signal losses.
  • To develop methods for obtaining uniformly diffusion-weighted images using spatial encoding.

Main Methods:

  • Analysis of diffusion effects in spatially encoded MRI sequences.
  • Characterization of signal loss along the spatially encoded dimension.
  • Adaptation of spatially encoded MRI sequences to mitigate diffusion-induced non-uniformities.

Main Results:

  • Diffusion-related signal losses are often non-uniform in the spatially encoded dimension.
  • Demonstrated a method to adapt spatially encoded sequences.
  • Achieved uniformly diffusion-weighted images.

Conclusions:

  • Diffusion significantly impacts image quality in spatially encoded MRI.
  • Sequence adaptation is crucial for uniform diffusion weighting.
  • The proposed method enhances image quality and reliability in diffusion-weighted spatial encoding.
Keywords:
Diffusion artifactsEcho planar imagingRASERSingle scan MRISpatially encoded MRI

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