Electronic Posters
: Diffusion & Perfusion - Neuro
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Mapping Structural Anisotropy : Kurtosis
Monday May 9th
Exhibition Hall |
14:00 - 16:00 |
Computer 84 |
14:00 |
4011. |
Estimation of
kurtosis in accelerated diffusion spectrum
imaging using compressed sensing ![](play.gif)
Jonathan Immanuel Sperl1, Ek
Tsoon Tan2, Kedar Khare2,
Kevin F King3, Xiaodong Tao2,
Christopher J Hardy2, Luca
Marinelli2, and Marion I Menzel1
1GE Global Research, Garching,
Germany, 2GE
Global Research, Niskayuna, NY, United
States, 3GE
Healthcare, Waukesha, WI, United States
Diffusion spectrum imaging provides radial
information of diffusivity in the brain,
such as diffusional kurtosis. This work
presents a two step quadratic programming
framework for fitting the diffusion and
kurtosis tensors. Furthermore, the effects
of using undersampled data and compressed
sensing recon-structions are investigated.
Various derived scalar measures for kurtosis
are compared for a human brain data set. The
results show the robustness of the fitting
procedure as compared to standard linear
fitting. Compressed sensing allows for
either faster acquisitions or improved image
quality, while providing some degree of
denoising.
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14:30 |
4012. |
Do commonly
used b-values yield accurate apparent kurtosis
values? ![](play.gif)
Tristan Anselm Kuder1, Bram
Stieltjes2, Wolfhard Semmler1,
and Frederik Bernd Laun1
1Medical Physics in Radiology,
German Cancer Research Center, Heidelberg,
Germany, 2Quantitative
Imaging-based Disease Characterization,
German Cancer Research Center, Heidelberg,
Germany
Diffusional kurtosis is usually measured by
fitting to the expansion of the logarithmic
signal in b terminated after the quadratic
summand. Since it is not clear, if
neglecting higher order terms is justified
for b-values typically applied in clinical
applications, in this work, the influence of
higher order terms was investigated for
different model geometries using computer
simulations and in phantom experiments. For
b-values typically used in vivo, the
measured kurtosis strongly deviates from the
correct value showing an important influence
of the higher order summands.
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15:00 |
4013. |
Diffusion
gradient correction in Diffusion Kurtosis
Imaging ![](play.gif)
Xiaowei Zou1, Jordan S. Muraskin1,
Melvyn B. Ooi2, and Truman R.
Brown3
1Biomedical Engineering, Columbia
University, New York, NY, United States, 2Stanford
University, 3Radiology,
Columbia University
Diffusion gradient correction in DKI that
resolves the inconsistence between gradient
vectors and realigned images.
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15:30 |
4014. |
A novel
Diffusion Kurtosis Imaging system using
heteroscedastic multiple regression ![](play.gif)
Xiaowei Zou1, and Truman R. Brown2
1Biomedical Engineering, Columbia
University, New York, NY, United States, 2Radiology,
Columbia University
A weighted global-fitting based Diffusion
Kurtosis Imaging system that significantly
improves reproducibility and robustness
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Electronic
Posters : Diffusion & Perfusion - Neuro
|
Click on
to view the abstract pdf and click on
to view the video presentation. |
Mapping Structural Anisotropy : Reconstruction & Morphometry
Tuesday May 10th
Exhibition Hall |
13:30 - 15:30 |
Computer 85 |
13:30 |
4015. |
Online Reconstruction and
Motion Detection in HARDI ![](play.gif)
Emmanuel Caruyer1, Iman Aganj2,
Christophe Lenglet3, Guillermo Sapiro2,
and Rachid Deriche1
1Athena Project-Team, INRIA Sophia Antipolis
- Méditerranée, Sophia Antipolis, France, 2Department
of Electrical and Computer Engineering, University of
Minnesota, Minneapolis, MN, United States, 3Department
of Radiology - CMRR, University of Minnesota Medical
School, Minneapolis, MN, United States
We demonstrate how Orientation Distribution Functions
(ODFs) can be estimated online from High Angular
Resolution Diffusion Imaging (HARDI) data and how this
procedure can efficiently be used to detect head motion
during acquisition.
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14:00 |
4016. |
Multiple Kernel Spherical
Deconvolution ![](play.gif)
Qiuyun Fan1,2, Xin Hong2, Nicole
Davis3,4, Laurie E. Cutting3,5,
and Adam W. Anderson1,2
1Department of Biomedical Engineering,
Vanderbilt University, Nashville, TN, United States, 2Vanderbilt
University Institute of Imaging Science, Nashville, TN,
United States, 3Vanderbilt
University Kennedy Center for Research on Human
Development, Nashville, TN, United States, 4Department
of Radiology and Radiological Sciences, Vanderbilt
University, Nashville, TN, United States, 5Department
of Special Education, Vanderbilt Peabody, Nashville, TN,
United States
DTI provides reproducible measures of fiber integrity,
although it is unable to resolve crossing fibers. HARDI
methods can resolve crossings, but do not provide
estimates of the intrinsic anisotropy in each fiber. In
this work, we propose an approach that resolves crossing
fibers and estimates the intrinsic diffusion properties
of each fiber. Multiple kernels are allowed in spherical
deconvolution and multiple shells in q-space are sampled
in order to estimate the kernel for each resolvable
fiber in a voxel. The results can potentially provide
more accurate analysis of the properties of fiber
pathways in the brain.
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14:30 |
4017. |
Brain Atlas-based Study of
the Interplay between Normal Tissue Microstructural MRI
Parameters ![](play.gif)
Indika S Walimuni1, and Khader M Hasan1
1Radiology, UTHSCH, Houston, Texas, United
States
A comprehensive investigation of the interplay between
microstructural MRI parameters such as T2 relaxation and
diffusivites using standardized volume-based methods in
both healthy gray and white matter has not been
attempted before. Advances in multimodal MRI
registration and segmentation methods have enabled the
fusion of high resolution T1, diffusion tensor imaging
and relaxation maps to a common native space provided by
a high resolution T1-weighted volume. This volume can be
anatomically labeled using atlases of white and gray
matter regionn. In this work, we investigated the
interplay between T2 relaxation and the radial
diffusivity using 82 brain white matter (WM), gray
matter (GM), cortical and subcortical structures. We
report, a strong relation between the T2 relaxation and
the radial diffusivity in a healthy population.
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15:00 |
4018. |
ODF-based morphometry and
application to brain asymmetry ![](play.gif)
Alvina Goh1, Neda Jahanshad2, Paul
M Thompson2, and Christophe Lenglet3
1Department of Mathematics, National
University of Singapore, Singapore, Singapore, 2Laboratory
of Neuro Imaging, Department of Neurology, UCLA, Los
Angeles, CA, United States, 3Department
of Radiology - CMRR, University of Minnesota Medical
School, Minneapolis, MN, United States
Orientation Distribution Functions (ODFs) are estimated
from High Angular Resolution Diffusion Imaging (HARDI)
data and provide a great amount of information on the
structure of the white matter. We present an extension
of voxel-based morphometry to ODFs and apply it to brain
asymmetry.
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Electronic
Posters
: Diffusion & Perfusion - Neuro
|
Click on
to view the abstract pdf and click on
to view the video presentation. |
Mapping Structural Anisotropy : Novel Contrast
Wednesday May 11th
Exhibition Hall |
13:30 - 15:30 |
Computer 86 |
13:30 |
4019. |
Diffusion properties
of whole, post-mortem human brains ![](play.gif)
Karla L Miller1, Charlotte J Stagg1,
Saad Jbabdi1, Heidi Johansen-Berg1,
and Jennifer A McNab2
1FMRIB Centre, University of Oxford,
Oxford, Oxon, United Kingdom, 2A.A.
Martinos Center, Massachusetts General Hospital,
Boston, MA, United States
Although diffusion imaging is sensitive to tissue
microstructure, biological interpretation of
diffusion properties is lacking. Imaging of
post-mortem brains would enable the comparison of
diffusion indices (such as MD and FA) with
histological samples. We present results of
diffusion imaging in whole, post-mortem human
brains. Diffusion properties are significantly
different than in vivo and depend on post-mortem
interval. However, anisotropy is partially preserved
and tractography is possible.
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14:00 |
4020. |
White matter fiber
orientation mapping based on T2* anisotropy ![](play.gif)
Jongho Lee1,2, Peter van Gelderen1,
Li-Wei Kuo1, Hellmut Merkle1,
Afonso C. Silva3, and Jeff H. Duyn1
1Advanced MRI section/LFMI/NINDS,
National Institutes of Health, Bethesda, MD, United
States, 2Department
of Radiology, University of Pennsylvania,
Philadelphia, PA, United States, 3CMU/LFMI/NINDS,
National Institutes of Health, Bethesda, MD, United
States
The dependence of T2* on fiber orientation relative
to B0 was studied in post-mortem human brain tissue.
We found an orientation dependence with sin2 and
sin4 ![lower case Greek theta](http://submissions.miracd.com/ISMRM2011/Images/LCGreek/theta.gif) components.
This dependence could be accurately explained by a
model of microscopic susceptibility variations
together with significant susceptibility anisotropy.
Based on this, we constructed a T2* orientation map
that closely resembled a fiber orientation map
derived from DTI.
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14:30 |
4021. |
Temporal Alterations
in Brain Water Diffusivity in Acute Radiation Injury ![](play.gif)
Richa Trivedi1, Hemanth Kumar Bhonsle
Somu1, Senthil Veeramani1,
Rajendra P Tripathi1, and Subash Khushu1
1Institute of Nuclear Medicine & Allied
Sciences, Delhi, Delhi, India
Longitudinal diffusion tensor imaging (DTI) study
was performed at baseline, 6 h, 1 day, 3 days and 5
days after a sub-lethal dose irradiation. Decreased
MD values were observed in brain parenchyma at 3rd
and 5th day compared to baseline study. Initial
increase in FA values was observed on moving from 0
hour to 1 day in CC and Ctx followed by a sharp
decrease in FA on 3rd and 5th day. No abnormalities
were visible on anatomical images. Our results
suggest the radiation-induced hypoxic changes in
brain parenchyma during acute phase even before
conventional MRI.
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15:00 |
4022. |
DTI Metrics
Differentiate Chronic Infective from Chronic
Inflammatory Knee Arthritis ![](play.gif)
Rishi Awasthi1, Vikas Agarwal2,
Deepak Tripathi2, Vinita Agarwal3,
R KS Rathore4, and Rakesh K Gupta1
1Departments of Radiodiagnosis, Sanjay
Gandhi Post Graduate Institute of Medical Sciences,
Lucknow, India, Lucknow, UP, India, 2Departments
of Immunology, Sanjay Gandhi Post Graduate Institute
of Medical Sciences, Lucknow, India, Lucknow, UP,
India, 3Departments
of Pathology, Sanjay Gandhi Post Graduate Institute
of Medical Sciences, Lucknow, India, Lucknow, UP,
India, 4Department
of Mathematics & Statistics, Indian Institute of
Technology, Kanpur, UP
A total of 17 patients (seven detected tubercular
and 10 with inflammatory arthritis) were imaged
using both conventional and DT MRI. It was found
that DTI derived FA and CL of synovial membrane were
significantly higher in tubercular arthritis as
compared to the non-tubercular ones. In synovial
fluid, apart from FA and CL, CP was also
significantly higher in tubercular arthritis, while
MD values were significantly lower than inflammatory
arthritis. We conclude that DTI can non-invasively
differentiate between chronic inflammatory arthritis
from tubercular arthritis which is of importance in
appropriate management of these patients.
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Electronic
Posters
: Diffusion & Perfusion - Neuro
|
Click on
to view the abstract pdf and click on
to view the video presentation. |
Mapping Structural Anisotropy : Acquisition & Pipeline
Thursday May 12th
Exhibition Hall |
13:30 - 15:30 |
Computer 87 |
13:30 |
4023. |
Diffusion weighted MR
nerve sheath imaging (DW-NSI) using diffusion-sensitized
driven-equiliblium (DSDE) ![](play.gif)
Makoto Obara1, Taro Takahara2,
Masatoshi Honda3, Thomas Kwee4,
Yutaka Imai3, and Marc Van Cauteren1
1Healthcare, Philips Electronics Japan,
Minato-ku, Tokyo, Japan, 2Department
of Biomedical Engineering, Tokai University School
of Engineering, Hiratsuka, Kanagawa, Japan, 3Department
of Radiology, Tokai University Hospital, Isehara,
Kanagawa, Japan, 4University
Medical Center Utrecht, Utrecht, Netherlands
The utility of motion compensation
diffusion-sensitized driven-equilibrium (MC-DSDE)
for diffusion-weighted nerve sheath imaging (DW-NSI)
from the C1 nerve to the T1 nerve was assessed and
compared to EPI-DWI and conventional DSDE sequences,
in human volunteers, at 3.0T. MC-DSDS was apparently
superior to the other sequences, with less
distortion and more smoothness, making it an
appropriate method for DW-NSI.
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14:00 |
4024. |
A Novel Interlaced
Sampling Scheme for Multi-Shell q-space
Magnetic Resonance Microscopy ![](play.gif)
Sharon Portnoy1, Wenxing Ye2,
Alireza Entezari2, Stephen J Blackband1,3,
and Baba C Vemuri2
1Department of Neuroscience, University
of Florida, Gainesville, Florida, United States, 2CISE
department, University of Florida, Gainesville,
Florida, United States,3National High
Magnetic Field Laboratory, Tallahassee, Florida,
United States
We propose a novel interlaced multi-shell q-space
sampling scheme, which uses two different polyhedra,
the icosidodecahedron and rhombic triacontahedron,
to determine the sample distributions on odd and
even q-shells. Comparison of simulated and acquired
MR data shows that the interlaced scheme provides
greater accuracy in the reconstruction of the 3D
diffusion propagator relative to standard
multi-shell schemes. Accuracy of the interlaced
method is improved even further by interpolation of
q-space samples onto a body-centered-cubic (rather
than Cartesian) sampling grid. These techniques
provide a significant improvement in our ability to
resolve the complex fibre architectures within
biological tissues.
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14:30 |
4025. |
Development and
Evaluation of A Robust and Efficient Computational
Pipeline for Track Density Imaging for Use in a Clinical
Research Environment ![](play.gif)
Cornelius von Morze1, Duan Xu1,
and Christopher P Hess1
1Department of Radiology and Biomedical
Imaging, UCSF, San Francisco, CA, United States
Track density imaging is an exciting new diffusion
post-processing method allowing visualization of
white matter tracks with super-resolution by
counting the number of tractographic tracks
traversing each voxel on a fine spatial grid. We
have developed a robust and efficient processing
pipeline for production of TDI images in a clinical
research environment. We have examined the initial
results from TDI in a set of normal volunteers and
patients at 3T.
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15:00 |
4026. |
Gaussian dephasing due
to finite gradients in q-space imaging ![](play.gif)
Frank Peeters1
1Université Catholique de Louvain,
Brussels, Brussels, Belgium
In q-space imaging (QSI), the averaged propagator of
the diffusion process can be obtained in terms of a
Fourier transform of the MR-signal. However, a
fundamental assumption in QSI is the so-called short
gradient approximation (SGA) which can not be
satisfied on clinical scanners. We present a new
formalism for QSI that is also valid for long
duration diffusion encoding gradients. It starts
from the basic equations for Brownian motion and
magnetic field gradient encoding. The general
solution of the resulting Fokker-Planck equation
shows that the effect of finite gradients is to make
the propagator more Gaussian.
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Electronic
Posters
: Diffusion & Perfusion - Neuro
|
Click on
to view the abstract pdf and click on
to view the video presentation. |
Integrated Software Packages
Tuesday May 10th
Exhibition Hall |
13:30 - 15:30 |
Computer 88 |
13:30 |
4027. |
Accelerating Diffusion
Tensor Estimation Using General-Purpose Graphics Processing
Unit ![](play.gif)
Lin-Ching Chang1, and Mikhail A Gorbachev1
1Department of Electrical Engineering and
Computer Science, The Catholic University of America,
Washington, DC, United States
A general-purpose graphics processing unit (GPU) offers
a powerful processing platform to accelerate
non-graphics applications such as tensor estimation in
Diffusion Tensor Imaging (DTI). Diffusion tensor maps
are computed on a voxel-by-voxel basis by fitting the
signal intensities of diffusion weighted images as a
function of their corresponding b-matrices. This
computation can be significantly accelerated by using
the GPU. This study presents the application of using
GPU hardware in diffusion tensor estimation by
accelerating the weighted multivariate linear
regression. The results are tested in simulated 3D brain
dataset and show faster computation time against the
CPU. The proposed GPU framework can accelerate DTI
simulation and can be readily applied to quantitative
assessment of the DTI using bootstrap analysis.
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14:00 |
4028. |
Diffusion Imaging in the
Medical Imaging Interaction Toolkit (MITK) ![](play.gif)
Klaus Hermann Fritzsche1, Marco Nolden1,
Hans-Peter Meinzer1, and Bram Stieltjes1
1German Cancer Research Center, Heidelberg,
Baden Württemberg, Germany
Q-ball imaging provides insights into aspects of brain
structure in living humans that could not be studied
previously. The lack of standardized and extensible
software tools for I/O, reconstruction, interactive
visualization, and statistics impedes development and
sustainable evaluation. The diffusion imaging component
of the Medical Imaging Interaction Framework (MITK-DI)
aims at supporting cutting edge diffusion imaging
techniques and, in contrast to most other frameworks,
addresses all aspects of application design including
full integration into an application platform and fluent
workflows. MITK-DI therefore allows covering the
complete cycle from raw-data to post processing and
statistics.
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14:30 |
4029. |
Extendable Multimodality
Imaging Framework with specific illustration of DTI ![](play.gif)
Divya Kishore Singh Rathore1, Sanjay K Verma2,
RKS Rathore2, and Rakesh K Gupta3
1Imaging R&D, ADISL, Kanpur, UP, India, 2Mathematics
and Statistics, Indian Institute of Technology, Kanpur,
UP, India, 3Departments
of Radiodiagnosis, Sanjay Gandhi Post Graduate Institute
of Medical Sciences, Lucknow, UP, India
A worldwide interest in research and development in MRI
and associated protocols over last 2 decades has
generated a need for tools and frameworks that allow
rapid development of research grade software. We propose
a plugin based architecture that allows developers to
add extended support for various file-formats,
post-processing algorithms, re-use of existing libraries
etc. As an illustration, we are describing a plugin for
post-processing of Diffusion Tensor MRI data.
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15:00 |
4030. |
DTI Processing and
Analysis with MedINRIA ![](play.gif)
Pierre Fillard1, and Nicolas Toussaint2
1Parietal Reseach Team, INRIA Saclay
Île-de-France, Gif/Yvette, France, 2Imaging
Sciences, King's College London, London, United Kingdom
Although the MedINRIA software has been out for three
years, it has never been formally presented to ISMRM.
The objective of this work is to expose the rationale
for the development of MedINRIA, a clinically oriented
medical image processing software, and to present its
DTI functionalities. We present the processing pipeline
going from DICOM to fiber tracts. Notably, it comprises
a unique anisotropic smoothing procedure enhancing the
tensor quality of datasets of moderate SNR typical of
clinical data. We further describe the interactive
tract-of-interest selection tool and show an example of
fiber bundle extraction and analysis with MedINRIA.
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