ISMRM 24th Annual Meeting & Exhibition • 07-13 May 2016 • Singapore

Weekend Educational Course: Diffusion MRI Light

Skill Level: Basic to Intermediate

Organizers: Daniel C. Alexander, Ph.D., Chunlei Liu, Ph.D. & Stephan E. Maier, M.D., Ph.D.

Saturday 07 May 2016

This course will introduce fundamental principles and methodologies of diffusion MRI. The first three lectures will focus on the basics of generating diffusion contrast in MRI, mathematical models for analyzing diffusion-encoded signals and methods for extracting microstructural information of tissues. The following two lectures will showcase the practical application of diffusion MRI in tractography and population studies. Ample opportunity will be provided for interaction between audience and speakers.

Target Audience
Physicists, technologists and clinicians, who wish to understand the basics and more advanced concepts and applications of diffusion MRI.

Educational Objectives
Upon completion of this course, participants should be able to:

  • Understand the concepts of diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI);
  • Comprehend the limitations of basic DTI and the need for more advanced diffusion models;
  • Recognize diffusion MRI approaches for characterizing tissue microstructure;
  • Know different methods for tractography and be aware of potential applications and limitations; and
  • Select group study approaches for diffusion data, both for cross-sectional and longitudinal cohorts.

Moderator: Chunlei Liu, Stephan Maier
Introduction to Diffusion Weighted Imaging
Ching-Po Lin1
1Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan
Diffusion MRI is a technique that can probe direction-dependent diffusivity of water molecules to reflect, on a statistical basis, the displacement distribution of the water molecules present within a MRI voxel.  The observation of this displacement distribution may thus provide unique clues to the structure and geometric organization of tissues.  Here, I will review the principle of diffusion MRI and its applications in neuroscience.

Diffusion Tensor Imaging & Higher Order Methods
Els Fieremans1
1Radiology, New York University School of Medicine, NY, United States
In this lecture, we will explore the non-Gaussian diffusion signal as measured in biological tisues by varying both the gradient wave vector q and the diffusion time t, the time over which the molecules diffuse. The concepts of q-space imaging, diffusion tensor imaging (DTI) and diffusion kurtosis imaging (DKI) will be covered, as well as other higher order diffusion methods. In addition, we will illustrate how varying the diffusion time t provides complimentary information about microstructural length scales. 

Probing Microstructure with Diffusion MRI
Markus Nilsson1
1Dept. of Diagnostic Radiology, Lund University
Diffusion MRI can be used to non-invasively quantify brain microstructure by using analysis methods and models more accurate than diffusion tensor imaging. Biophysical models of diffusion MRI describe the MR signal as originating from diffusion in distinct tissue components, such as the intra-axonal or extracellular space. Comparment sizes, e.g., the average axon diameter, can be estimated using diffusion MRI, provided that the size is above the resolution limit of the acquisition protocol. Orientation dispersion is essential to include in white matter diffusion models.

Break & Meet the Teachers
Diffusion Tractography: Principles & Methods
Maxime Descoteaux1
1Computer Science, Université de Sherbrooke
The audience will learn the basic principles of diffusion tractography and be cautious of the limitations of current methods. In particular, the audience will learn the difference between Diffusion Tensor Imaging (DTI) and High Angular Resolution Diffusion Imaging (HARDI) tracotgraphy, from both a deterministic and probabilistic point of view.

Applying Diffusion MRI in Population Studies
Ragini Verma
The talk will cover various aspects of processing and analysis of diffusion data, from the perspective of population studies. Specifically it will discuss connectome creation, connectomic analysis, automated tract extraction and biomarker creation. In addition to describing the protocol for cross-sectional studies, we will also discuss the extension of these methods to longitudinal studies.  In addition to the description of methods, application to clinical populations will be presented.

Panel Discussion
Adjournment & Meet the Teachers

The International Society for Magnetic Resonance in Medicine is accredited by the Accreditation Council for
Continuing Medical Education to provide continuing medical education for physicians.