| Non-Proton MRI |
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Thursday 23 April 2009 |
| Room 315 |
10:30-12:30 |
Moderators: |
Navin Bansal and Christian Beaulieu |
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10:30 |
609. |
Non-Invasive, Whole-Brain CMRO2
Mapping of the Human Brain |
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Ian C. Atkinson1,
Keith R. Thulborn1
1Center for MR Research, University of
Illinois at Chicago, Chicago, IL, USA |
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An MR-based technique
for whole-brain CMRO2 mapping is introduced and
demonstrated in the human brain. This new approach
incorporates a biologically based model of metabolic
water production and persistence and accounts for
brain tissue mass. Unlike positron emission
tomography based CMRO2 approaches, this new
technique allows CMRO2 maps to be obtained from
humans without radioactive tracers or invasive
measurements. |
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10:42 |
610. |
Performance of Hyperpolarized
1,4-13C2 Fumarate in a Murine
Lymphoma Model in Vivo, a New Diagnostic
Agent for Oncology |
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Pernille Rose Jensen1, Rene in 't
Zandt1, Magnus Karlsson1, Anna
Gisselsson1, Georg Hansson1,
Mathilde Hauge Lerche1
1Imagnia AB, Malmö, Sweden |
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We have developed
hyperpolarized 1,4-13C2
fumarate as a new promising metabolic marker for
oncology. Metabolic parameters like up-take and
conversion significantly influences imaging
parameters like timing and concentration. Here we
show a comparison between two substrates,
hyperpolarized 1-13C pyruvate, which
previously has been shown to be an oncology marker1,
and the new agent, 1,4-13C2
fumarate. In a mouse EL-4 lymphoma model, the
optimal timing and concentration are determined
after which the SNR and contrast for the two
substrates in the metabolic images are evaluated and
compared. |
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10:54 |
611. |
Dual Resolution Simultaneous
19F/1H In Vivo Imaging
of Targeted Nanoparticles |
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Jürgen Rahmer1,
Jochen Keupp1, Shelton D. Caruthers2,3,
Oliver Lips1, Todd A. Williams3,
Samuel A. Wickline3, Gregory M. Lanza3
1Philips Research Europe, Hamburg, Germany;
2Philips Healthcare, Andover, MA, USA;
3Washington University, St. Louis, MO,
USA |
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19F-labeled diagnostic
or therapeutic agents, like targeted perfluorocarbon
nanoparticles, offer a high potential for quantified
molecular MRI with excellent specificity. For
anatomical co-registration of the fluorine signal, a
proton image of the morphology is needed.
Simultaneous 19F/1H imaging was shown to be an ideal
approach to timeefficient recording of molecular
information and morphology. An unmet need of truly
simultaneous imaging is to satisfy the substantially
different requirements on sensitivity and resolution
between the 19F and 1H acquisition, while being
constrained to a single choice of gradient
strengths. This work presents in vivo results
of angiogenesis-targeted imaging of Vx-2 tumors in
rabbits, demonstrating that 3D radial simultaneous
acquisition offers an SNR-efficient way to acquire
19F and 1H images at different resolutions at the
same time. The basic principle is to modify the
weight applied to samples in the gridding
reconstruction. |
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11:06 |
612. |
Sodium and Proton Diffusion
MRI of Rodent Glioma Therapy at 21 T |
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Victor D. Schepkin1,
Cathy W. Levenson2, Silvia M. Figueiroa3,
William W. Brey1, Peter L. Gor'kov1,
Kiran K. Shetty1
1CIMAR, NHMFL/FSU, Tallahassee, FL, USA;
2College of Medicine, Florida State
University, Tallahassee, FL, USA; 3College
of Human Sciences, Florida State University,
Tallahassee, FL, USA |
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Rodent glioma
chemotherapy was investigated using for the first
time MRI at 21T. Tumor responses were detected by
high resolution sodium and proton diffusion MRI in
non-treated and BCNU treated 9L tumors. Steady
increase of tumor sodium content in non-treated
tumor was detected with a rate of ~ 5%/day. Both
sodium and diffusion MRI can identify therapeutic
response in a few days but can predict outcome only
in ~ two weeks after initiation of therapy. The
study supports the unique role of sodium homeostasis
in tumors and the importance of sodium and diffusion
MRI in evaluating and predicting efficacy of
therapy. |
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11:18 |
613. |
Noninvasive Monitoring of CCl4
Induced Acute and Chronic Liver Damage in Rat by SQ
and TQF 23Na MRI |
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Yong Gao1,
Judy James1, Navin Bansal1
1Radiology, Indiana University School of
Medicine, Indianapolis, IN, USA |
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Single-quantum (SQ) and
triple-quantum-filtered (TQF) 23Na MRI
and shift-reagent- (SR-) aided 23Na and
31P MRS were employed to monitor the
progression of liver injury by CCl4
intoxication of rats. Acute high-dose CCl4
(2.5 ml/kg) caused increase in SQ and TQF 23Na
MRI signal intensity (SI) due to an increase in
intracellular [Na+]. Chronic low-dose CCl4
(0.5 ml/kg twice weekly for 8 weeks) caused an
increase in SQ SI due to increased extracellular
space, and an increase in TQF SI due to
extracellular fibroses. 23Na MRI may
prove useful in diagnosis of liver diseases because
of its sensitivity to liver injury. |
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11:30 |
614. |
Sodium MR Imaging at 3T Using
an 8-Channel 23Na and 2-Channel 1H
Rx/Tx Coil: Optimization and RF Inhomogeneity
Corrections |
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Judy Rose James1,2,
Chen Lin1, Ulrike Dydak1,2,
Andriy M. Babsky1, Helmut Stark3,
Brian M. Dale4, Navin Bansal1,2
1Radiology, Indiana University School of
Medicine, Indianapolis, IN, USA; 2School
of Health Sciences, Purdue University, West
Lafayette, IN, USA; 3MRI Coils Research,
Stark Contrast, Erlangen, Germany; 4Siemens
Medical Solutions, Cary, NC, USA |
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Initial 23Na
MR images of the human torso acquired at 3-Tesla
using an 8-channel dual tuned 23Na/1H
transmit/receive coil after RF inhomogeneity
corrections are presented. 23Na images
were obtained with 0.3 cm spatial resolution and ~20
SNR in ~15 min with clear delineation between
different abdominal organs and their sub-regions.
These images were acquired with imaging parameters
optimized under SAR limits for human scans. The
ability to perform 23Na MRI in clinical
settings is useful to non-invasively detect and
diagnose diseases in various body organs due to the
physiological significance of trans-membrane sodium
gradient that is critical for cell survival. |
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11:42 |
615. |
Dynamic MRSI for
Hyperpolarized [1-13C]-Pyruvate with
Multiband Pulses Applied in the TRAMP Prostate
Cancer Mouse Model |
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Peder E. Z. Larson1,
Robert Bok1, Adam B. Kerr2,
Albert P. Chen3, Simon Hu1,
Matthew L. Zierhut1, Michael Lustig2,
John M. Pauly2, Sarah J. Nelson1,
John Kurhanewicz1, Daniel B. Vigneron1
1Radiology and Biomedical Imaging, University
of California - San Francisco, San Francisco, CA,
USA; 2Electrical Engineering, Stanford
University, Stanford, CA, USA; 3Global
Applied Science Lab, GE Healthcare, Toronto,
Ontario, Canada |
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We have applied a new
serial, time-resolved 13C MRSI
acquisition method for metabolic imaging in the
TRansgenic Adenocarcinoma of Mouse Prostate (TRAMP)
mouse model in order to investigate the uptake and
metabolic dynamics within tumors and in normal
tissues following injection of hyperpolarized
pyruvate. This new method is based on tailored
multiband excitation pulses that preserve the
magnetization over time. The prostate tumors have
characteristically high lactate conversion and, as
this study showed, a characteristic dynamic curve.
The results demonstrated significant tumor
heterogeneity, with variations in pyruvate
perfusion/uptake and lactate conversion. |
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11:54 |
616. |
In-Vivo Ultra-Fast
Spectroscopic Imaging of 19F Containing
Contrast Agents |
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Rolf Lamerichs1,
Caren van Kammen2, Muhammed Yildirim1,
Klaas Nicolay3
1Philips Research, Eindhoven, Netherlands;
2Maastricht University, Maastricht,
Netherlands; 3Eindhoven University of
Technology, Eindhoven, Netherlands |
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Imaging of fluorine
based contrast agents can play a major role in the
context of Molecular Imaging. Here we show the
in-vivo feasiblity of fast spectroscopic imaging
of such agents. |
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12:06 |
617. |
Spin-Lock Sodium MRI of the
Human Brain: A Preliminary Study |
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David Thomas
Pilkinton1, Mark A. Elliott1,
Jeremy F. Magland2, Ravinder Reddy1
1Biochemistry and Molecular Biophysics,
University of Pennsylvania, Philadelphia, PA, USA;
2Department of Radiology, University of
Pennsylvania, Philadelphia, PA, USA |
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In this preliminary
study, spin-lock sodium MRI was used to image
agarose and human brain. Although measurements of T2
or T2* are sensitive to slow motion through the
spectral density at zero frequency, slow dynamics
are probed more efficiently through the application
of a strong RF field near the kilohertz range. We
demonstrate in sodium images of brain tissue and
agarose that spin-locking provides significant
contrast for macromolecular content due to its
sensitivity to spins in slow molecular motion
regimes. |
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12:18 |
618. |
Faster Sodium MRI Through TPI-SENSE:
Results at 7T |
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Yongxian Qian1,
Graham Wiggins2, Lawrence L. Wald2,
Fernando E. Boada1
1Department of Radiology, University of
Pittsburgh, Pittsburgh, PA, USA; 2Department
of Radiology, Massachusetts General Hospital,
Massachusetts, MA, USA |
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This study presents
parallel sodium (23Na) images of human brain on a
whole-body 7T scanner using a 15-channel array coil
and demonstrates the potential benefits of the TPI-SENSE
technique in accelerating data acquisition. Our
initial results shows that an acceleration of 2x3
(ring x rotation) is achievable using TPI-SENSE
sodium parallel imaging with a 15-channel array coil
without significant degradation in image quality |
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