Seeing the Invisible with Diffusion -Weighted Magnetic Resonance
Seeing the Invisible
with Diffusion-Weighted Magnetic Resonance
Evren Özarslan1,2
1Section on Tissue Biophysics and Biomimetics, Program on Pediatric
Imaging and Tissue Sciences, Eunice Kennedy Shriver National Institute
of Child Health and Human Development, National Institutes of Health
2Center for Neuroscience and Regenerative Medicine, Uniformed Services University of the Health Sciences
Conventional magnetic resonance (MR) imaging scans suffer from limited
resolution that prohibits the visualization of individual cells thus
providing information at coarse length scales. To obtain information at
smaller length scales, the MR signal can be sensitized to
self-diffusion of water molecules whose motional history is influenced
by the local microstructure. Starting from the fundamentals, I will
discuss the essential features of diffusion MR that makes it a powerful
probe to characterize tissue and material microstructure. Emphasis will
be placed on an alternative diffusion MR pulse sequence, the double
pulsed field gradient (double-PFG) technique, that could be used to
characterize the size, shape, and orientational distribution of
cellular compartments without the need to apply strong magnetic field
gradients. Theoretical predictions as well as early experimental
findings demonstrate that double-PFG MR could be a powerful technique
for monitoring morphological changes in tissue, and, as such, a
valuable diagnostic tool.
Evren Özarslan graduated with a Bachelor of Science in Physics from the
University of Illinois at Urbana-Champaign in 1999. He obtained his
M.S. degree in Biomedical Engineering in 2003 and Ph.D. in Physics in
2004, both from the University of Florida. Since 2005 Dr. Özarslan has
been a member of the Section on Tissue Biophysics and Biomimetics
(STBB) at the National Institutes of Health (NIH). Starting October
this year, Dr. Özarslan assumed a scientist position with the Henry M.
Jackson Foundation, and has been continuing his research jointly at the
Center for Neuroscience and Regenerative Medicine and STBB. His current
research is on physical modeling of biological tissue and other porous
media with the specific aim of characterizing the microstructure of the
specimen using noninvasive magnetic resonance based techniques. Dr.
Özarslan's research is interdisciplinary in nature, and has in common
with a wide range of disciplines, from magnetic resonance imaging and
image processing to mathematical, chemical, and biological physics.
*Faculty Candidate Seminar