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ISMRM 21st
Annual Meeting & Exhibition
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20-26 April 2013
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Salt Lake City, Utah, USA |
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TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY |
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TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
MRS of Neurological Disease
1938.
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Proton MR Spectroscopy
Correlates Diffuse Axonal Injury with Post-Concussive
Symptoms in Mild Traumatic Brain Injury 
Ivan I. Kirov1, Assaf Tal1,
James S. Babb1, Joseph Reaume1,
Tamara Bushnik2, Teresa A. Ashman2,
Steven Flanagan2, Robert I. Grossman1,
and Oded Gonen1
1Radiology, New York University, New
York, NY, United States, 2Rusk
Institute of Rehabilitation Medicine, New York
University, New York, NY, United States
There are no established biomarkers for mild
traumatic brain injury (mTBI), in part because
post-concussive symptoms (PCS) are subjective and
conventional imaging is typically unremarkable. To
test whether diffuse axonal injury (DAI) quantified
with three-dimensional (3D) proton magnetic
resonance spectroscopic imaging (1H-MRSI) correlated
with patients’ PCS we retrospectively studied 26mTBI
patients (mean Glasgow Coma Scale score of 14.7),
18–56 years old, 3 – 55 days post injury and 13
controls. All were scanned at 3 Tesla with
T1-andT2-weighted MRI and 3D 1H-MRSI (480 voxels
over 360 cm3, ~30% of the brain). On scan day
patients completed a symptom questionnaire and those
indicating at least one of the most common subacute
mTBI symptoms (headache, dizziness, sleep
disturbance, memory deficits, blurred vision) were
grouped as PCS-positive. Global gray- and white
matter (GM/WM) absolute concentrations of N-acetylaspartate
(NAA), choline (Cho), creatine (Cr) and myo-inositol
(mI) in PCS-positive and PCS-negative patients were
compared to age- and gender-matched controls using
two-way analysis of variance. The results showed
that PCS-negative group (n=11) and controls (n=8)
did not differ in any GM or WM metabolite level. The
PCS-positive patients (n=15) had lower WM NAA than
the controls (n=12): 7.0±0.6 versus 7.9±0.5mM
(p=0.0007). Global WM NAA, therefore, showed
sensitivity to the DAI sequelae associated with
common PCS in patients with mostly normal
neuroimaging as well as GCS scores. This suggests a
potential biomarker role in a patient population in
which objective measures of injury and
symptomatology are currently lacking.
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1939. |
7 T 1H
MRS Detects a Human Brain Glutathione (GSH) Response to
N-Acetylcysteine, an Antioxidant Precursor, in Patients
with Gaucher and Parkinson’s Disease
Melissa Terpstra1, Mary Holmay1,
Lisa Coles1, Usha Mishra1,
Matthew Ahlskog1, James Cloyd1,
Paul Tuite1, and Gulin Oz1
1University of Minnesota, Minneapolis,
MN, United States
One distinguishing attribute of MR is its utility to
noninvasively monitor therapeutic response. N-acetylcysteine
(NAC) is under investigation for the treatment of
several conditions. One possible mechanism for
efficacy against neurodegenerative disease is as a
precursor for the formation of the antioxidant
glutathione (GSH). In this study, human brain GSH
concentrations were measured using 7 T 1H
MRS throughout intravenous infusion of NAC. The
occipital cortex GSH concentration increased by at
least 10 % (mean 33 %, SD 17 %) in all 8
participants after delivery of NAC, indicating a
strong group effect (p < 0.001).
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1940. |
Volumetric MR
Spectroscopic Imaging with Reduced K-Space Acquisitions:
Variability and Pathologic Detectability in Mild
Traumatic Brain Injuries
Mohammad Sabati1, Jiping Zhan1,
Varan Govind1, Kristopher L. Arheart2,
and Andrew A. Maudsley1
1Radiology, University of Miami, Miami,
FL, United States, 2Epidemiology
and Public Health, University of Miami, Miami, FL,
United States
Several parallel imaging (PI) techniques have been
developed for MRSI to reduce data acquisition times.
MRSI methods, however, are often
sensitivity-limited, and only a few reports have
studied the resultant impact that PI may have when
applied to MRSI on the outcome of diagnostic
accuracy. It therefore remains unknown whether the
clinical diagnostic value is maintained for
PI-enabled MRSI to detect subtle pathology? This
question is addressed by implementing a GRAPPA-MRSI
within a fully-automated data processing pipeline
and evaluating it using subjects with mild traumatic
brain injury who represents a patient group for
which the metabolic changes are relatively subtle
and diffuse.
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1941. |
The Longitudinal
Relaxation Time of GABA in
vivo at
3T
Nicolaas A. J. Puts1,2, Peter B. Barker1,2,
and Richard Anthony Edward Edden1,2
1The Russell H. Morgan Department of
Radiology and Radiological Science, Johns Hopkins
University, Baltimore, Maryland, United States, 2FM
Kirby Centre for functional neuroimaging, Kennedy
Krieger Institute, Baltimore, Maryland, United
States
The longitudinal relaxation time of GABA was
measured in vivo using a MM-suppression method and a
saturation recovery experiment.
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1942. |
Reduced Basal Ganglia
GABA in Attention Deficit Hyperactivity Disorder
Steffen Bollmann1,2, Carmen Ghisleni1,2,
Simon S. Poil1,2, Peter Klaver1,3,
Lars Michels1,4, Richard Anthony Edward
Edden5, Ernst Martin1,2,
Dominique Eich-Höchli6, Juliane Ball7,
Daniel Brandeis7,8, and Ruth L. O'Gorman1,2
1Center for MR-Research, University
Children's Hospital, Zurich, Zurich, Switzerland, 2Center
for Integrative Human Physiology (ZIHP), University
of Zurich, Zurich, Switzerland, 3Institute
of Psychology, University of Zurich, Zurich,
Switzerland, 4Institute
of Neuroradiology, University Hospital of Zurich,
Zurich, Switzerland, 5Department
of Radiology and Radiological Science, Johns Hopkins
University, Baltimore, MD, United States, 6Psychiatric
University Hospital, University of Zurich, Zurich,
Switzerland,7Department of Child &
Adolescent Psychiatry, University of Zurich, Zurich,
Switzerland, 8Central
Institute of Mental Health Mannheim, Medical Faculty
Mannheim/ Heidelberg University, Mannheim, Germany
This study examines differences in basal ganglia
GABA levels between adults with ADHD and healthy
participants, and evaluates the association between
GABA levels and ADHD symptom scores. GABA-edited MR
spectra were acquired with MEGA-PRESS, and symptom
scores were evaluated with the Wender Utah Rating
scale and Conners symptom inventories. GABA/Cr
levels in the basal ganglia were lower in ADHD
patients relative to controls, and GABA levels
correlated negatively with WURS hyperactivity scores
and Conners hyperactive, impulsive, and inattentive
scores, indicating that patients with ADHD have
reduced inhibitory neurotransmitter levels in the
left basal ganglia which are related to behavioural
dysfunction.
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1943. |
Longitudinal Evaluation
of Mild Traumatic Brain Injury: A H-MRS Study
Elijah George1,2, Steven Roys1,3,
Jiachen Zhuo1, Chandler R. Sours4,
Jacqueline Janowich1, Teodora Stoica1,
and Rao P. Gullapalli1
1Magnetic Resonance Research Center,
University of Maryland School of Medicine,
Baltimore, MD, United States, 2Bioengineering,
University of Maryland, College Park, MD, United
States, 3Diagnostic
Radiology & Nuclear Medicne, University of Maryland
School of Medicine, Baltimore, MD, United States, 4Program
in Neuroscience, University of Maryland School of
Medicine, Baltimore, MD, United States
Mild traumatic brain injury (mTBI) patients
represent 75% of the viable TBI population. The aim
of the current study is to carry out a longitudinal
evaluation of mTBI by monitoring metabolic markers
of mTBI and their evolution over time such that the
findings realized herein will aid improved clinical
evaluation of the pathology. We combined neuro-metabolic
information with neuropsychological test (NPT) data
for the purpose of understanding how current
metabolic state affects ongoing cognitive
capability, and to determine the efficacy of neuro-metabolic
information acquired acutely in predicting outcome
of mTBI patients.
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1944. |
Age-Related Metabolite
Alterations in Adolescents with High Functioning Autism,
an 1H-MRS Study
Evelien M. Barendse1, Albert P. Aldenkamp1,
Roy PC Kessels2, Marc P.H. Hendriks2,
Geert Thoonen1, Paul A.M. Hofman3,
Walter H. Backes3, and Jacobus F.A.
Jansen3
1Epilepsy Centre Kempenhaeghe, Heeze, NB,
Netherlands, 2Neuropsychology,
Radboud University Nijmegen, Nijmegen, Ge,
Netherlands, 3Radiology,
Maastricht University Medical Center, Maastricht,
Li, Netherlands
In this cross-sectional study, we investigate the
effect of age and intelligence on occipital
metabolite concentrations in adolescents (aged
13-19y) with high functioning autism (HFA) and
healthy controls. We observed that 1H-MRS provides
evidence of atypical membrane metabolism development
in HFA, which potentially underlies the observed
atypical behavioral development in autism.
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1945. |
Neurochemical Changes
in Rat Brain After 5-Fluorouracil Chemotherapy Assessed
by 1H
MR Spectroscopy at 9.4 T
Ryutaro Nakagami1,2, Masayuki Yamaguchi1,
Yoshifumi Abe3, Tatsuhiro Hisatsune3,
Akira Furukawa2, and Hirofumi Fujii1
1Division of Functional Imaging, National
Cancer Center Hospital East, Kashiwa, Chiba, Japan, 2Graduate
School of Health Sciences, Tokyo Metropolitan
University, Arakawa-ku, Tokyo, Japan, 3Graduate
School of Frontier Sciences, University of Tokyo,
Kashiwa, Chiba, Japan
Recent studies have reported that some cancer
patients who received chemotherapy experienced mild
cognitive impairment. Although the mechanism of this
type of cognitive impairment is not fully
understood, preliminary studies suggested that
chemotherapy may induce neurotransmitter deficits,
damaging cognitive function. Investigation of brain
metabolite changes using in
vivo MR
spectroscopy may help to understand the mechanism of
chemotherapy-induced cognitive impairment. In this
study, we assessed metabolite changes in the brains
of rats that received 5-FU (100 mg/kg) chemotherapy
using 1H
MR spectroscopy at 9.4 Tesla.
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1946. |
Effects of Binge Acute
Ethanol Intoxication on Cerebral Neurochemical Profile
in Rats: Evidence from in
vivo Proton
Magnetic Resonance Spectroscopy
Do-Wan Lee1, Jae-Hwa Kim2,
Sang-Young Kim1, Dai-Jin Kim2,3,
Jinyoung Jung1, and Bo-Young Choe1
1Department of Biomedical Engineering,
The Catholic University of Korea, College of
Medicine, Seoul, Seoul, Korea, 2Department
of Biomedical Science, The Catholic University of
Korea, College of Medicine, Seoul, Seoul, Korea, 3Department
of Psychiatry, Seoul St. MaryˇŻs Hospital, The
Catholic University of Korea, College of Medicine,
Seoul, Seoul, Korea
This study aimed to quantitatively assess the
cerebral neurochemical effects in hippocampal region
in binge ethanol-intoxicated rats by using a 4.7-T
1H-MR Spectroscopy. Our results showed that total
choline (tCho; phosphocholine+glycerophosphocholine)
concentrations, and tCho/total N-acetylaspartate (tNAA:
NAA+N-acetylaspartylglutamate [NAAG]) ratios were
significantly lower in binge ethanol group than that
in control group. Significantly low tCho
concentrations and tCho/tNAA ratios may indicate the
cell membrane turnover abnormalities of
phosphatidylcholine and changed adaptive mechanism
in the hippocampus of binge ethanol intoxicated
rats. Thus, we provide quantitative in vivo evidence
that binge ethanol exposure causes cerebral
neurochemical profile changes in rats, in
hippocampal region.
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TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
Human MRS: In Vivo & In Vitro
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1947. |
Therapeutic Blood Glucose
Control Effects Cerebral Glycolysis Following Traumatic
Brain Injury
Stephanie M. Wolahan1, David McArthur1,
Paul Vespa1, Neil A. Martin1, and
Thomas C. Glenn1
1Department of Neurosurgery, UCLA, Los
Angeles, CA, United States
Managing glucose after traumatic brain injury (TBI) is a
major concern and the effect of two glycemic control
strategies (tight vs. loose) on TBI patients are
compared. We hypothesize that cerebral glucose is
metabolized differently depending on plasma glucose
levels and that lactate is increasingly metabolized when
systemic glucose is low. Results show that when glucose
is kept low (tight glycemic control) there is increased
glycolytic glucose metabolism but less lactate released
into the blood than when glucose is at higher levels.
This supports the theory that the injured brain
generates energy from lactate when systemic glucose is
low.
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1948. |
Cholesterol and Its Esters
as Serum Biomarkers in Malignant Obstructive Jaundice: A
Single Step 1H NMR Metabonomic Approach
Abhinav A. Sonkar1, Shatakshi Srivastava2,
Santosh Kumar Singh1, Hari Om Gupta1,
Devendra Singh1, Jitendra Kushwaha1,
Abhijit Chandra3, and Raja Roy2
1SURGERY, KG MEDICAL UNIVERSITY, Lucknow,
UTTAR PRADESH, India, 2CBMR,
SGPGI, Lucknow, UTTAR PRADESH, India, 3GASTROSURGERY,
KG MEDICAL UNIVERSITY, Lucknow, UTTAR PRADESH, India
The paucity of biomarkers for malignant obstructive
jaundice results in formidable morbidity and mortality
rates. Therefore, alternative diagnostic measures are
required for pre-operative management of patients. In
the present study, 1H NMR-based metabonomics approach
has been applied to investigate small metabolites,
cholesterol and bile acid metabolism in benign and
malignant causes of obstructive jaundice (OBJ) for
identification of serum and bile biomarkers for improved
clinical interpretation. A newer, rapid and single step
method for serum cholesterol : cholesterol esters
estimation has been found to be efficient in
differentiating malignancy.
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1949. |
NMR-Based Metabolite
Profiling of Fecal Extracts from Colorectal Cancer in China:
An Initial Study
Yan Lin1, ChengKang Liu1, ZhiWei
Shen1, and RenHua Wu1
1Medical Imaging Department, Second
Affiliated Hospital, Shantou University Medical College,
Shantou, Guang Dong, China
This preliminary results based on 1H NMR spectroscopy
and partial least squares discriminant analysis (PLS-DA)
demonstrated that metabolites differences of fecal
extracts between CRC patients and healthy controls can
be identified that may be important in the early
detection of CRC in China. The observed low levels of
SCFA (acetate, butyrate and propionate) are consistent
with previous reports[3,4], which has been associated
with the development of colorectal cancer, seems to be
the most effective marker of fecal extracts for
differentiating CRC patients from healthy controls.
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1950. |
Fast Determination of
Absolute Metabolite Concentrations by Spatially-Encoded 2D
NMR: Application to Breast Cancer Cell Extracts
Serge Akoka1, Adrien Le Guennec1,
Illa Tea1, Estelle Martineau1,
Benoit Charrier1, Meerakhan Pathan1,
and Patrick Giraudeau1
1Chemistry, Université de Nantes, Nantes,
France
Absolute metabolite concentrations from complex
metabolic mixtures were measured using an approach based
on a “multi-scan single shot” (M3S) strategy (derived
from ultrafast 2D NMR). The analytical performance was
compared to the one of conventional 2D NMR. On model
metabolic mixtures, the precision was in the 1-4% range
(versus 5-18% for the conventional approach),
highlighting the superiority of the M3S approach for
quantitative analysis. The M3S COSY approach was then
applied to measure the absolute metabolite concentration
of 14 major metabolites in three breast cancer cell line
extracts, showing significant differences between cell
lines.
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1951. |
A Multimodal Investigation
of Neuronal/Axonal Integrity Using Structural T1-Weighted
Imaging, Diffusion Tensor Imaging, and 1H
MR Spectroscopy
Soyoung Choi1, Anand A. Joshi2,
Chitresh Bhushan2, Vincent J. Schmithorst3,
Stefan Bluml4, David W. Shattuck5,
Richard M. Leahy2, Hanna Damasio1,
Ashok Panigrahy3, and Jessica L. Wisnowski3,6
1Dana and David Dornsife Cognitive
Neuroscience Imaging Institute, University of Southern
California, Los Angeles, California, United States, 2Signal
and Image Processing Institute, University of Southern
California, Los Angeles, California, United States, 3Radiology,
Children's Hospital of Pittsburgh of UPMC, Pittsburgh,
PA, United States, 4Department
of Radiology, Children Hospital of Los Angeles, Los
Angeles, CA, United States, 5Laboratory
of Neuro Imaging, UCLA School of Medicine, Los Angeles,
CA, United States, 6Brain
and Creativity Institute, University of Southern
California, Los Angeles, California, United States
Multimodal magnetic resonance (MR) imaging is
increasingly becoming the standard in clinical practice
and research yielding synergistic information regarding
brain structure and brain function. We examined the
relations among the absolute concentration of of
n-acetyl-aspartate (NAA; quantitated from MR
spectroscopy), fractional anisotropy (FA) and
diffusivity metrics (ADC, AD, RD) calculated from DTI
scans and volumetric and cortical surface area
measurements computed from T1-weighted scans in
standardized GM and WM regions. Our most significant
findings were of associations between NAA and both FA
and RD metrics in the white matter and suggest that
together these metrics reflect neuronal/axonal packing
density.
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1952. |
Assessment of Hippocampal
Activation and Resting State Glutamate Concentration by
Using Functional MRI and 1H
MR Spectroscopic Imaging
Alexander Gussew1, Gerd Wagner2,
Andreas Deistung3, Reinhard Rzanny1,
Patrick Hiepe1, Marianne Cleve1,
Karl-Jürgen Bär4, and Jürgen R. Reichenbach1
1Medical Physics Group, Department of
Diagnostic and Interventional Radiology I, Jena
University Hospital, Jena, Thuringia, Germany, 2Centre
for Neuroimaging, Department of Psychiatry and
Psychotherapy, Jena University Hospital, Jena,
Thuringia, Germany, 3Medical
Physics Group, Department of Diagnostic and
Interventional Radiology I, Jena University Hospital -
Friedrich Schiller University Jena, Jena, Thuringia,
Germany, 4Pain
& Autonomics group, Department of Psychiatry and
Psychotherapy, Jena University Hospital, Jena,
Thuringia, Germany
The present work describes multimodal fMRI and 1H-CSI
measurements of memory task induced functional
alternations in hippocampal activity and relationships
of these changes to the resting state concentrations of
the excitatory neurotransmitter glutamate in a group of
healthy volunteers. Significant positive BOLD
activations were detected bilaterally in the posterior
hippocampus. Task induced activation revealed positive
correlation with glutamate concentration, indicating
regulation of neuronal activity by the excitatory
neurotransmitter turnover.
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1953. |
GABA Measured by 1H-MRS
Is Not Affected by Tiagabine.
C. John Evans1, Jim F. M. Myers2,
Nicola Kalk2, Richard Anthony Edward Edden3,
and Anne Lingford-Hughes4
1CUBRIC, School of Psychology, Cardiff
University, Cardiff, Wales, United Kingdom, 2Psychopharmacology
Unit, University of Bristol, Bristol, United Kingdom, 3Russell
H. Morgan Department of Radiology and Radiological
Science, Johns Hopkins University, Baltimore, MD, United
States, 4Neuropsychopharmacology
Unit, Imperial College London, London, United Kingdom
Tiagabine, an antiepileptic drug, acts by blocking the
reuptake of inhibitory neurotransmitter GABA from the
synapse, thus increasing GABA concentration at the
synaptic cleft. We performed J-difference edited 1H-MRS
before and after tiagabine administration to investigate
whether MRS was sensitive to changes in extracellular
GABA concentration. Ten participants were studied, and
MRS data were acquired from occipital and limbic voxels.
No significant change was detected in GABA, thus
indicating that although tiagabine has GABAergic action,
it does not affect the total GABA concentration.
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1954. |
Metabolic Trends in
Thalamic Development from Infancy to Adulthood Measured
Using Magnetic Resonance Spectroscopy
Andrew J. Degnan1,2, Vince Lee2,
Rafael C. Ceschin2, Vincent J. Schmithorst2,
Stefan Blüml3, and Ashok Panigrahy2
1University of Pittsburgh Medical Center,
Pittsburgh, PA, United States, 2Department
of Radiology, Children's Hospital of Pittsburgh,
Pittsburgh, PA, United States, 3Department
of Radiology, Children's Hospital Los Angeles, Los
Angeles, CA, United States
Magnetic resonance spectroscopy is capable of offering
insight into the developing brain. In this study, we
report changes in the metabolite concentrations within
the thalamus from healthy term neonates to young adults.
In this study we note a more mature metabolite profile
in the thalamus in neonates when compared with grey and
white matter, consistent with other knowledge of the key
role of thalamic development in early life. Knowledge of
normal metabolic changes within this key structure
explained by this study is essential in understanding
thalamocortical deficits in the setting of preterm
injury.
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TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
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1955. |
Metabolite Concentration
Changes During Motor Activation Using Functional Magnetic
Resonance Spectroscopy (FMRS) at 7T
Benoît Michel Schaller1, Lijing Xin2,
Kieran O'brien3, and Rolf Gruetter4
1Laboratory of Functional and Metabolic
Imaging, Ecole Polytechnique Fédérale de Lausanne,
Lausanne, Vaud, Switzerland, 2Department
of Radiology, University of Lausanne, Lausanne, Vaud,
Switzerland, 3Centre
d'Imagerie BioMédicale, University of Geneva, Geneva 14,
Geneva, Switzerland, 4Laboratory
of Functional and Metabolic Imaging, École Polytechnique
Fédérale de Lausanne, Lausanne, Vaud, Switzerland
Functional Magnetic Resonance Spectroscopy (fMRS) allows
to investigate the small metabolite changes (<0.2µmol/g)
following a physiological stimulation, by acquiring
continuously MR spectra, and provides direct insights
into brain metabolism. In this study, a group analysis
revealed an increase of [Lac] of 28±3% and of [Glu] 3±1%
during motor activation.This study establishes that it
is possible to investigate the neurochemical profile
changes during motor activation. [Lac] and [Glu]
increase as has been observed during visual stimulation.
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1956. |
Increased Brain Lactate
Concentrations Without Increased Lactate Oxidation During
Hypoglycemia in Type 1 Diabetic Individuals with
Hypoglycemia Unawareness
Henk M. De Feyter1, Graeme F. Mason2,
Gerald I. Shulman3, Douglas L. Rothman4,
and Kitt Falk Petersen5
1Diagnostic Radiology, Yale University, New
Haven, CT, United States, 2Dept.
of Psychiatry, Yale University, New Haven, CT, United
States, 3Howard
Hughes Medical Institute, Yale University, New Haven,
CT, United States, 4Diagnostic
Radiology, Yale University, New Haven, Connecticut,
United States, 5Internal
Medicine, Yale University, New Haven, CT, United States
Previous 13C
MRS studies have lead to the hypothesis that
upregulation of blood-brain barrier monocarboxylic acid
(MCA) transport may contribute to maintenance of brain
energetics during hypoglycemia in subjects with
hypoglycemia unawareness. We examined transport and
metabolism of [3-13C]-lactate in brain of
type 1 diabetic patients with hypoglycemia unawareness
and non-diabetic control subjects during a hypoglycemic
clamp using 13C
MRS. We found that brain lactate concentrations were
markedly increased in type 1 diabetic subjects.
Surprisingly we observed no increased oxidation of
blood-borne lactate in the type 1 diabetic subjects
suggesting that other metabolic adaptations may
contribute to hypoglycemia unawareness.
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1957. |
In Vivo Determination
of de Novo Lipogenesis
in Rat Liver Using Localized 1H-[13C]
Magnetic Resonance Spectroscopy
Sharon M. Janssens1, Klaas Nicolay1,
and Jeanine J. Prompers1
1Biomedical NMR, Eindhoven University of
Technology, Eindhoven, Netherlands
De novo lipogenesis is the primary pathway in which
excess carbohydrates are being converted to fat in
liver. The aim of this study was to develop a
non-invasive method for the direct in vivo measurement
of de novo lipogenesis in rat liver using localized 1H
MRS with 13C editing. Before and after the oral
administration of [U-13C6] glucose for 5 days, total and
13C-enriched intrahepatocellular lipid (IHCL) content
were measured with 1H-[13C] MRS. After 5 days of
[U-13C6] glucose administration, total as well as
13C-enriched IHCL was increased, the latter being the
result of de novo lipogenesis.
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1958. |
Can 13C
MRS Be Used to Monitor Changes in Hepatic Glycogen Levels
Following a Low Dose Oral Glucose Challenge?
S. Bawden1, Mary C. Stephenson1,
Elisabetta Ciampi2, J. Lane2, Luca
Marciani3, P Morris1, I MacDonald4,
Guru P. Aithal4, K. Hunter2, and
Penelope A. Gowland1
1SPMMRC, University of Nottingham,
Nottingham, Notts, United Kingdom, 2Unilever
Discover, Bedford, Beds, United Kingdom, 3NDDC
Biomedical Research Unit, University of Nottingham,
Nottingham, Notts, United Kingdom, 4Medical
School, University of Nottingham, Nottingham, Notts,
United Kingdom
This study investigates the lower limits of sensitivity
in measuring changes in hepatic glycogen levels
following an oral glucose challenge using in vivo
natural abundance Carbon-13 MR spectroscopy. Subjects
were scanned following an overnight fast for baseline
values and then hourly for five hours following either a
50g glucose dose or control using a multi-nuclear
surface coil. Spectra glycogen peak areas over the
timecourse were compared between groups. Changes in
gastric content and liver volume we also monitored to
consider other related effects. Results show that
hepatic glycogen AUCs were significantly higher in the
glucose challenge group compared with control.
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1959. |
Quantification of Fatty
Acids in Human Calf Adipose Tissue and Muscle by 13C
MRS Using J-Refocused PRESS DEPT and ERETIC
Xing Chen1, Peter Boesiger1, and
Anke Henning2,3
1Institute for Biomedical Engineering,
Zurich, Zurich, Switzerland, 2University
and ETH Zurich, Zurich, Zurich, Switzerland, 3Max
Planck Institute of Biological Cybernetics, Tübingen,
Tübingen, Germany
A J-refocused proton PRESS localized DEPT sequence is
applied to achieve reliably localized and SNR enhanced
signals by in vivo 13C MRS using volume coil, with the
combination of optically transmitted and inductively
coupled ERETIC as a reference for absolute
quantification. The proposed method is used to assess
the fatty acids from human deeper locations: calf tibial
bone marrow and skeletal muscle, among omnivores,
vegetarians and vegans. Both relative percentages and
absolute molar concentrations are evaluated and
analyzed. The results demonstrate the applicability of
quantitative, SNR enhanced and localized 13C MRS for
large scale noninvasive investigation of the impact of
dietary intake, physical exercise or pathology on fatty
acid metabolism and related diagnosis.
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1960. |
In Vivo Magnetic
Resonance Spectroscopy of Lipid Handling in Steatotic Rat
Liver
Sharon M. Janssens1, Richard AM Jonkers1,
Mattijs Heemskerk2, Sjoerd A. van den Berg2,
Ko Willems van Dijk2, Natal A. van Riel3,
Klaas Nicolay1, and Jeanine J. Prompers1
1Biomedical NMR, Eindhoven University of
Technology, Eindhoven, Netherlands, 2Department
of Human Genetics, Leiden University Medical Center,
Leiden, Netherlands,3Eindhoven University of
Technology, Eindhoven, Netherlands
Hepatic steatosis is het abnormal and excessive
accumulation of triglycerides in the liver and is a
hallmark of non-alcoholic fatty liver disease (NAFLD).
The aim of this study was to determine differences in in
vivo lipid metabolism in steatotic livers of rats on
different high-fat diets using 1H MRS with 13C editing
in combination with the oral administration of
13C-labeled lipids. Animals on a high-fat diet developed
liver steatosis accompanied by a significantly reduced
lipid turnover in the liver.
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1961. |
Human Studies of Functional
MRS at 7T with Semi-LASER
Petr Bednarik1,2, Ivan Tkac1,
Andrea Grant1, Uzay E. Emir1,
Dinesh K. Deelchand1, and Silvia Mangia1
1CMRR - Dept. of Radiology, University of
Minnesota, Minneapolis, MN, United States, 2Molecular
and Functional Imaging Laboratory, CEITEC - Central
European Institute of Technology, Masaryk University,
Brno, Czech Republic
In the present work we measured brain metabolite
concentrations during a visual stimulation paradigm at 7
T with a full-intensity 1H MRS sequence, semi-LASER. In
excellent agreement with our previous findings obtained
with STEAM sequence, we observed significant
concentration changes within ± 0.2 µmol/g for lactate,
glutamate, aspartate and glucose. However, we could not
detect changes in glutathione, glycine, glutamine and
GABA as reported in other studies, despite higher MRS
sensitivity. We conclude that the latter concentration
changes are likely to be ascribed to the particular
settings of the visual stimulation paradigm.
|
|
1962. |
Spectroscopic Imaging of
Metabolites with 2D Heteronuclear Multiple Quantum Coherence
in Mouse
Hirohiko Imai1, Yuki Takayama1,
and Tetsuya Matsuda1
1Department of Systems Science, Graduate
School of Informatics, Kyoto University, Sakyo-ku,
Kyoto, Japan
We demonstrate a spatially encoded 2D heteronuclear
multiple quantum coherence (HMQC) spectroscopy for
imaging metabolites. A standard chemical shift imaging
(CSI) incorporated with 2D 1H-13C
HMQC preparation was implemented in a tumor-bearing
mouse after sacrifice at 30min post injection of [U-13C]glucose.
The 4D data acquisition (two spectral and two spatial
dimensions) allows the identification of multiple
metabolites with 1H
sensitivity and 13C
spectral resolution, and the visualization of their
distribution throughout the whole body. As the result,
the increase of relative amount of lactate was observed
in the brain, tumor, and inferior limb.
|
|
1963. |
Clinical 3.0 T 13C
MRS: Net Hepatic Glycogen Breakdown During 19 Hr Fast
Paul Begovatz1, Sabine Kahl1,
Bettina Nowotny1, Juergen Bunke2,
Michael Roden1,3, and Jong-Hee Hwang1
1Institute of Clinical Diabetology, German
Diabetes Center, Duesseldorf, Germany, 2Philips
Healthcare, Hamburg, Germany, 3Department
of Metabolic Diseases, University Clinics, Heinrich
Heine University, Duesseldorf, Germany
13C-MRS is the only method to non-invasively measure
changes in net hepatic glycogen concentrations which is
of interest regarding the pathophysiology of type 2
diabetes. These measurements have traditionally been
conducted on MR-systems designed for spectroscopy,
however expansion to FDA approved scanners would play a
vital role in clinical research. Proton decoupled
C1-glycogen peaks were detected with SNRs ranging from
32:1 at 514mM, to 5:1 at 106mM, with a COV=12%. Rates of
net hepatic glycogen breakdown in vivo were 5.53±0.22
µmol/kgBW/min, consistent with previous studies. This
proves that the methods outlined here can be implemented
for use in clinical trials.
|
|
1964. |
Exercise Does Not Modulate
Postprandial Lipid Uptake in Liver and Skeletal Muscle of
Healthy and Diabetic Rats
Richard AM Jonkers1, Sharon M. Janssens1,
Klaas Nicolay1, Luc JC van Loon2,
and Jeanine J. Prompers1
1Biomedical Engineering, Eindhoven University
of Technology, Eindhoven, Netherlands, 2Department
of Human Movement Sciences, Maastricht University
Medical Centre+, Maastricht, Netherlands
Insulin resistance has been associated with ectopic
lipid accumulation. Physical activity improves insulin
sensitivity, but the impact of exercise on lipid
handling in insulin-resistant skeletal muscle and liver
remains to be elucidated. The present study
characterizes postprandial lipid handling in liver and
muscle of healthy and diabetic rats after one hour of
treadmill running using in
vivo 13C-edited 1H-MRS
in combination with 13C-labeled
lipid administration. We showed that muscle but not
liver lipid stores represent a viable substrate source
during exercise in healthy and diabetic rats. However,
postprandial lipid uptake in liver and muscle was not
affected by prior exercise.
|
|
1965. |
Kinetic Model-Based
Analysis of Dynamic 31P MRS Data on ATP Metabolism in Rat
Hindlimb Muscle
Jeroen A. Jeneson1, Ranjan Dash2,
Daniel A. Beard2, and Robert W. Wiseman3
1Center for Systems Biology of Energy
Metabolism and Ageing, University Medical Center
Groningen, Groningen, Netherlands, 2Physiology,
Medical College of Wisconsin, Milwaukee, WI, United
States, 3Physiology
and Radiology, Michigan State University, East Lansing,
MI, United States
Dynamic 31P NMR spectroscopy has longtime been used to
probe the homeostatic performance of the integrated
biochemical networks involved in cellular energy balance
in a variety of human diseases including heart failure
and diabetes. Recent advances in computational modeling
of these biochemical networks now offer a tool to link
these macroscopic 31P MRS observations to the rich
knowledge base on the molecular components interacting
in these networks. Here, we explore the potential of
such kinetic model-based analysis of dynamic 31P MRS
recordings of ATP metabolism in muscle to extract
information on the activity of a key mitochondrial
enzyme, Pyruvate Dehydrogenase.
|
|
1966. |
Neuronal and Astroglial
Metabolism in APP-PS1 Mouse Model of Alzheimer's Disease
with Progress of Age
Vivek Tiwari1, Pandichelvam Veeraiah1,
and Anant Bahadur Patel1
1NMR Microimaging and Spectroscopy,
CSIR-Centre for Cellular and Molecular Biology,
Hyderabad, A.P., India
Alzheimer's disease (AD) is associated with deficit and
dysfunction of neurotransmitters and synapses. Cerebral
metabolic fluxes were measured in APP-PS1 mouse model of
AD with the progress of age by using 1H-[13C]-NMR
spectroscopy in conjunction with infusion of 13C
labeled glucose and acetate. APP-PS1 mice exhibit normal
neurochemical profile and cerebral metabolism at very
early age. At the preclinical age, neuronal metabolism
is found to be impaired without any change in the level
of neurometabolites. In addition to impaired neuronal
metabolism and neurochemical profile, the APP-PS1 mice
exhibit higher astroglial activity at the late age of
the disease.
|
|
1967. |
Nonlinear Laplacian
Eigenmaps Dimension Reduction of in-vivo Magnetic
Resonance Spectroscopic Imaging Analysis
Guang Yang1, Felix Raschke1,
Thomas Richard Barrick1, and Franklyn A. Howe1
1Division of Clinical Sciences, St. George’s
University of London, London, United Kingdom
MRSI has demonstrated great clinical potential as a
supplement to standard imaging for non-invasive
diagnosis of brain tumours. Pattern recognition(PR)
techniques are used to assist MRSI tumour identification
and characterisation, and they can be applied to MRSI
data with suspected gliomas with an aim to segment
regions relating to tumour core, tumour infiltration and
normal brain. Dimensionality reduction(DR) is an
important prerequisite in any real case of PR. In this
work, we advocate the spectral manifold learning method
of Laplacian eigenmaps as a DR technique suitable for
MRSI datasets, with correlation to standard MRI to aid
confirmation of our results.
|
|
1968. |
Slow Training Effect on
Intracellular Lipid in Skeletal Muscle
Yoshikazu Okamoto1, Tomonori Isobe1,
and Graham J. Kemp2
1University of Tsukuba Hospital, Tsukuba,
Ibaraki, Japan, 2University
of Liverpool, Liverpool, Liverpool, United Kingdom
How slow training work to the fat metabolism in the
muscle?
|
|
1969. |
in vivo Investigation
of Choline Compounds with 1H and 31P MRS in the Patients
with Liver Disorders.
Martin Gajdosik1, Ladislav Valkovic1,
Marek Chmelik1, Stefan Traussnigg2,
Michael Trauner2, Siegfried Trattnig1,
and Martin Krssák1,3
1MR Centre of Excellence, Department of
Radiology, Medical University of Vienna, Vienna,
Austria, 2Gastroenterology
& Hepatology, Department of Internal Medicine III,
Medical University of Vienna, Vienna, Austria, 3Endocrinology
& Metabolism, Department of Internal Medicine III,
Medical University of Vienna, Vienna, Austria
The measurements of choline containing compounds in the
liver lack the clean conclusion. In this study the link
between 1H & 31P MR spectroscopy (MRS) regarding to
choline containing compound and hepatic lipids in
patients with liver disorders - non-alcoholic fatty
liver disease and steatohepatitis was examined. The MRS
measurements allowed to resolve the resonances of
choline containing metabolites and we could find certain
links between proton and phosphorus MRS derived measures
of hepatic metabolism status.
|
|
1970. |
31P Magnetic Resonance
Spectroscopic Imaging of the Breast; Influence of the
Menstrual Cycle
Bertine L. Stehouwer1, Wybe J.M. van der Kemp1,
Peter R. Luijten1, Maurice A.A.J. van den
Bosch1, Wouter B. Veldhuis1,
Jannie P. Wijnen1, and Dennis W.J. Klomp1
1Radiology, University Medical Center
Utrecht, Utrecht, Netherlands
We investigated the phosphomonoester / phosphodiester
ratio in the breast of healthy females, and the
influence of the menstrual cycle on the ratio, using 31P
magnetic resonance spectroscopy at 7.0 Tesla. Five
premenopausal and five postmenopausal women were
included. A variation in ratio’s was seen throughout the
menstrual cycle, however no particular pattern could be
objectified. The ratio always remained <1. When using
31P MRS in a clinical setting a variation between women
and between moments in the menstrual cycle has to taken
into account.
|
|
1971. |
Signal-To-Noise Ratio
Analysis of 31P MRS in Skeletal Muscle: Influence of
Localization Schemes, RF Coils and Field Strength
Georg Bernd Fiedler1,2, Albrecht Ingo Schmid1,2,
Sigrun Goluch1,2, Ewald Moser1,2,
and Martin Meyerspeer1,2
1Center for Medical Physics and Biomedical
Engineering, Medical University of Vienna, Vienna,
Vienna, Austria, 2MR
Centre of Excellence, Medical University of Vienna,
Vienna, Vienna, Austria
In this study the SNR of 31P MRS with FID, STEAM and
semi-LASER acquisitions with single-loop and 3-channel
coils were compared at 3 and 7T in human muscle in vivo.
The PCr-peak's SNR from semi-LASER measurements in the
gastrocnemius at 7T with an optimized three channel coil
was similar to the SNR obtained with the
well-established non-localized acquisition scheme at 3T
using a single-loop coil. Localized 31P MRS at 7T, can
therefore be used to acquire localized data with similar
quality and temporal resolution, but with much higher
specificity than standard pulse-acquire MRS used for
dynamic studies of metabolism at 3T.
|
|
1972. |
Cerebral Metabolic Response
to Methylene Blue: A 31P
Magnetization Transfer Study at 11.7T
Andrew Bresnen1, Fang Du1,
Geoffrey Clarke2, and Timothy O. Duong3
1Research Imaging Institute, University of
Texas Health Science Center at San Antonio, San Antonio,
TX, United States, 2Radiological
Sciences, University of Texas Health Science Center at
San Antonio, San Antonio, TX, United States, 3UT
Health Science Center at San Antonio, San Antonio, TX,
United States
Methylene blue (MB) has unique energy-enhancing and
antioxidant properties. MB shows remarkable therapeutic
effects in a number of neurological disorders, including
Alzheimer's and Parkinson's diseases and traumatic and
ischemic brain injury. In vitro studies have
demonstrated that MB enhances mitochondrial ATP
production via oxidative phoysphorylation, however the
effects of MB on in vivo metabolites and metabolic rates
remain unknown. In this study, we implemented 31P NMR
based on the Four Angle Saturation Transfer method for
rapid in vivo measurements of the effects of MB on
relative concentrations of ATP, phosphocreatine and
inorganic phosphorus and the forward creatine kinase
(CK) rate.
|
|
|
TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
1973.
|
Effects of Cafeteria Diet
and Voluntary Running on Brain Structure and Metabolism in
Mice
Markus Sack1,2, Johannes Fuss3,
Claudia Falfán-Melgoza2, Sarah Biedermann1,2,
Matthias Auer4, Jenny Lenz4,
Gabriele Ende1, Alexander Sartorius2,5,
Peter Gass3, and Wolfgang Weber-Fahr1,2
1Neuroimaging, Central Institute of Mental
Health, Medical Faculty Mannheim / Heidelberg
University, Mannheim, Germany, 2RG
Translational Imaging, Central Institute of Mental
Health, Medical Faculty Mannheim / Heidelberg
University, Mannheim, Germany, 3RG
Animal Models in Psychiatry, Central Institute of Mental
Health, Medical Faculty Mannheim / Heidelberg
University, Mannheim, Germany, 4Endocrinology,
Max Planck Institute of Psychiatry, Munich, Germany, 5Psychiatry
and Psychotherapy, Central Institute of Mental Health,
Medical Faculty Mannheim / Heidelberg University,
Mannheim, Germany
Obesity is one of the major health burdens of modern
societies associated with a great variety of
health-threatening sequela such as diabetes,
cardiovascular diseases, cancer and even psychiatric
disorders. We conducted a MR spectroscopy study
investigating metabolic changes in a cafeteria-mouse
model vs. control mice receiving standard chow in the
right hippocampus and prefrontal cortex area in
conjunction with VBM analyses. We found that physical
exercise and cafeteria diet have opposite effects. While
exercising mice show increased metabolite concentrations
(NAA+NAAG and Glu+Gln) and increased volume within the
hippocampal area, cafeteria diet counterparts the
metabolic effect without impact on brain structure.
|
|
1974. |
Spectroscopic Imaging of
Brain Metabolism in a Mouse Model of Human Glioma-Initiating
Cells: A Longitudinal Study at 14.1 T
Mélanie Craveiro1, Cristina Cudalbu1,
Denis Marino2, Ivan Radovanovic2,
Virginie Clément-Schatlo2, and Rolf Gruetter3,4
1Laboratory for Functional and Metabolic
Imaging, Ecole Polytechnique Fédérale de Lausanne,
Lausanne, Switzerland, 2Department
of Clinical Neurosciences, University Hospital of
Geneva, Geneva, Switzerland, 3Laboratory
for Functional and Metabolic Imaging, École
Polytechnique Fédérale de Lausanne, Lausanne,
Switzerland, 4Departments
of Radiology, Universities of Lausanne and Geneva,
Lausanne and Geneva, Switzerland
Mouse models of human gliomas have been developed by
injection of fresh or cultured glioma-initiating cells (GIC),
leading to slow infiltrative or fast developing and
aggressive brain tumours. However, although brain
tumours have been extensively studied, only a few
studies have focused on the metabolic changes during
their development. In this study, we imaged the
metabolic changes occurring during tumour growth after
an injection of cultured GIC using proton magnetic
resonance spectroscopic imaging, which allowed for
sensitive tumour detection prior to any visual signs on
anatomical images, thus insuring an optimal evaluation
of the first metabolite alterations.
|
|
1975. |
In Vivo 13C
MRS Investigation of Alterations in Cerebral Oxidative
Metabolism in a Chronic Liver Disease Rat Model
Bernard Lanz1,2, Cristina Cudalbu2,
Valérie A. McLin3, Mario Lepore2,
Olivier Braissant4, and Rolf Gruetter5,6
1Department of Radiology, University of
Lausanne, Lausanne, Switzerland, 2Laboratory
for Functional and Metabolic Imaging (LIFMET), Ecole
Polytechnique Fédérale de Lausanne, Lausanne,
Switzerland, 3Département
de l'Enfant et de l'Adolescent, Unité de
Gastroentérologie, Hépatologie et Nutrition, Hôpitaux
Universitaires de Genčve (HUG), Geneva, Switzerland, 4Laboratoire
de Chimie Clinique, Département de Pathologie et de
Médecine de Laboratoire, Centre Hospitalier
Universitaire Vaudois and University of Lausanne,
Lausanne, Switzerland, 5Laboratory
for Functional and Metabolic Imaging (LIFMET), École
Polytechnique Fédérale de Lausanne, Lausanne,
Switzerland,6Departments of Radiology,
Universities of Lausanne and Geneva, Lausanne and
Geneva, Switzerland
13C MRS combined with the infusion of 13C-labeled
glucose is a powerful tool to investigate brain energy
metabolism in animal models. In the present study, we
analyzed the effect of hepatic encephalopathy induced by
chronic liver disease (CLD) on brain oxidative
metabolism, using bile duct ligated rats as model for
CLD.
|
|
1976. |
Dietary Restriction
Recovers Cerebral Activity in Pitx3 Knockout Mouse Model of
Parkinson’s Disease
Puneet Bagga1, Anup Nirmal Chugani1,
M Suresh Kumar1, and Anant Bahadur Patel1
1NMR Microimaging and Spectroscopy,
CSIR-Centre for Cellular and Molecular Biology,
Hyderabad, Andhra Pradesh, India
Pitx3 knockout (Pitx3-/-) mouse model is a
well characterized genetic model of Parkinson’s disease
(PD) due to malformation of substantia nigra leading to
loss of dopamine innervations in striatum. Dietary
restriction (DR) is linked with longevity and
neuroprotection via many mechanisms. Regional cerebral
metabolism was monitored by infusion of [1,6-13C2]glucose
for 10 min in conjunction with 1H-[13C]-NMR
spectroscopy of mice brain extracts. Glucose oxidation
by Glutamatergic and GABAergic neurons was decreased,
additionally thalamus-hypothalamic excitatory activity
and neurotransmission was found to be reduced in Pitx3-/- mice
which was observed to be recovered after 6 months of DR.
|
|
1977. |
Effect of Maternal Exposure
to High Fat Feeding on Cardiac Metabolism and Function in
Offspring
Petronella A. van Ewijk1,2, Sabina
Paglialunga1, Anne Gemmink3, Jos
M.G.M. Slenter2, Joachim E. Wildberger2,
Jan F. Glatz4, Joris Hoeks1,
Matthijs K.C. Hesselink3, Patrick Schrauwen1,
Vera B. Schrauwen-Hinderling1,2, and Marianne
Eline Kooi2
1Human Biology, Maastricht University Medical
Centre, Maastricht, Limburg, Netherlands, 2Radiology,
Maastricht University Medical Centre, Maastricht,
Limburg, Netherlands,3Human Movement
Sciences, Maastricht University Medical Centre,
Maastricht, Limburg, Netherlands, 4Molecular
Genetics, Maastricht University Medical Centre,
Maastricht, Limburg, Netherlands
We investigated in mice whether maternal exposure to a
high fat (HF) diet increases susceptibility for cardiac
lipotoxicity in male offspring on a HF-diet. Cardiac
MR-spectroscopy showed initially higher cardiac lipid
content in the HF/HF group (at 15 weeks) which decreased
in this group with time and tended to be lower at 27
weeks compared to LF/HF. Cardiac CINE-MR imaging showed
unchanged ejection fraction. Maximal mitochondrial
respiration (determined ex vivo) tended to be lower the
HF/HF group at 28 weeks. Maternal HF exposure lead to an
initially elevated cardiac lipid content however, on the
longer term, differences did not persist.
|
|
1978. |
Impaired Pyruvate
Carboxylase and Pentose Phosphate Pathway in APP-PS1 Mouse
Model of Alzheimer’s Disease
Anant Bahadur Patel1 and
Vivek Tiwari1
1NMR Microimaging and Spectroscopy,
CSIR-Centre for Cellular and Molecular Biology,
Hyderabad, Andhra Pradesh, India
Alzheimer’s Disease (AD) is one of the most common
neurodegenerative disorders characterized by progressive
memory impairment, disordered cognitive functions and
perturbed synaptic transmission. The present study
evaluates metabolic fluxes via pyruvate carboxylase
(PC), pentose phosphate (PPP) and pyruvate dehydrogenase
(PDH) pathways in 20 months old APP-PS1 mouse brain by
using 1H-[13C]-NMR
spectroscopy in conjunction with infusion of [2-13C]glucose.
Our results indicate that fluxes through PC, PPP and PDH
pathways are severely impaired in 20 months old APP-PS1
mice.
|
|
1979. |
ex vivo Quantification
of Regional Cerebral Metabolites in Chronic Alcohol
Consumption-Induced Rats
Do-Wan Lee1, Sang-Young Kim1,
Taehyeong Lee2, Anes Ju3, Hwi-Yool
Kim2, Dai-Jin Kim3,4, and Bo-Young
Choe1
1Department of Biomedical Engineering, The
Catholic University of Korea, College of Medicine,
Seoul, Seoul, Korea, 2Department
of Veterinary Surgery, Konkuk University of Korea,
Seoul, Seoul, Korea, 3Department
of Biomedical Science, The Catholic University of Korea,
College of Medicine, Seoul, Seoul, Korea, 4Department
of Psychiatry, Seoul St. Mary's Hospital, College of
Medicine, The Catholic University of Korea, Seoul,
Seoul, Korea
The aim of this study was to quantitatively investigate
the chronic ethanol-induced cerebral metabolic changes
in various regions of the rat brain, using the proton
HR-MAS NMR spectroscopy technique. Our results showed
that the levels of 2 to 7 metabolites were significantly
altered in five brain regions of the ethanol-treated
group, compared to the control group. Our key finding is
that the Glu/tCr and Cho/tCr ratio levels showed the
most significant differences in the thalamus of the rat
brain. These increased metabolic ratio levels of the
thalamus could be utilized as the key marker in the
human chronic alcoholism.
|
|
1980. |
1H-[13C]-NMR
Study to Evaluate the Efficacy of Levodopa Treatment in MPTP
Mouse Model of Parkinson’s Disease
Anant Bahadur Patel1, Anup Nirmal Chugani1,
Rajeeva Voleti1, and Puneet Bagga1
1NMR Microimaging and Spectroscopy,
CSIR-Centre for Cellular and Molecular Biology,
Hyderabad, Andhra Pradesh, India
MPTP is widely used chemical model to study the
pathophysilogy of Parkinson’s disease. Levodopa is the
most successful drug used for the treatment of
Parkinson’s disease. Efficacy of levodopa for improving
cerebral metabolism in MPTP treated mice was evaluated
by 1H-[13C]-NMR
spectroscopy in conjunction with infusion of [1,6-13C2]glucose.
Cortical and striatal glucose oxidation by glutamatergic
and GABAergic neurons, and total neurotransmission were
found to be reduced in MPTP treated mice. Acute levodopa
treatment improves the cerebral metabolism to the
control level.
|
|
1981. |
Hippocampal Neurochemical
Changes in Neonatal Mouse Model of Phlebotomy-Induced Anemia
Ivan Tkac1, Diana Wallin2, Tara
Zamora2, Kathleen Ennis2, Ariel
Stein2, Michael K. Georgieff2, and
Raghavendra Rao2
1Center for Magnetic Resonance Research,
University of Minnesota, Minneapolis, MN, United States, 2Department
of Pediatrics, University of Minnesota, Minneapolis, MN,
United States
In vivo 1H
NMR spectroscopy was used to investigate changes in the
neurochemical profile of the hippocampus of 14-day old
anemic mice (Hct = 20 ± 2%). Anemia was induced by
periodic blood draws during postnatal period P3 – P14.
Small, but significant changes were observed in
myo-inositol, lactate and phosphoethanolamine levels,
which indicate myelination changes in the developing
brain resulted from iron deficiency. These results
suggest that uncompensated phlebotomy-induced blood loss
is a risk factor, especially for preterm infants, and
has implications on blood transfusion practices.
|
|
|
TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
1982.
 |
Combination of a Sodium
Birdcage Coil with a Tunable Patch Antenna for B0 Shimming
and Anatomical Localization at 9.4 T
Christian C. Mirkes1,2, Jens Hoffmann1,
Gunamony Shajan1, Rolf Pohmann1,
and Klaus Scheffler1,2
1High-Field MR Center, Max Planck Institute
for Biological Cybernetics, Tübingen, Germany, 2Department
for Biomedical Magnetic Resonance, University of
Tübingen, Tübingen, Germany
X-nucleus spectroscopy and imaging normally rely on
proton imaging for anatomical localization and B0
shimming. A convenient way to perform these tasks,
without having to make any changes to the X-nucleus
coil, is presented here by the usage of the travelling
wave concept and a two-channel proton patch antenna.
|
1983.
|
Adaptive Combination of
Multichannel Data for Non-Proton MRI
Stefan H. Hoffmann1, Florian M. Meise1,2,
Armin Biller3, and Armin M. Nagel1
1Dpt. of Medical Physics in Radiology, German
Cancer Research Center (DKFZ), Heidelberg, Germany, 2Siemens
AG, Healthcare Sector, Magnetic Resonance, Erlangen,
Germany, 3Dpt.
of Neuroradiology, University Hospital Heidelberg,
Heidelberg, Germany
With the use of phased array receiver coils for
non-proton MRI a large gain in SNR can be achieved.
However, because of the intrinsically low SNR of the
data the standard sum-of-squares (SoS) reconstruction is
suboptimal and leads to a severe noise floor in the
images. We showed that a multichannel reconstruction
with the adaptive combination (AC) of the channels is
highly beneficial in non-proton MRI. In vivo SNR maps of
the AC multichannel reconstruction method of phased
array data acquired with a 30-channel 23Na
head coil at 3T are presented and a comparison with the
standard SoS reconstruction is given.
|
1984.
|
A Measurement Setup for
Combined Chlorine (35Cl) and Sodium (23Na)
MRI of the Human Brain
Armin M. Nagel1, Titus Lanz2,
Dominik Berthel2, Frank Resmer2,
Wolfhard Semmler1, and Reiner Umathum1
1Dpt. of Medical Physics in Radiology, German
Cancer Research Center (DKFZ), Heidelberg, Germany, 2Rapid
Biomedical, Rimpar, Germany
A dual tuned head coil for combined 35Cl/ 23Na
imaging is presented. For evaluating sensitivity
optimization, two versions were built: one with a 23Na
trap in the 35Cl
resonator, one without. By including 23Na
traps into the 35Cl
resonator, the B1 efficiency
of 35Cl
versus 23Na
can be controlled. The version with 23Na
traps was evaluated in phantom and in vivo imaging. Both
channels show good B1 efficiency
and SNR performance. The presented setup allows for
combined 23Na/ 35Cl
MRI without repositioning of the patient.
|
|
1985. |
In Vivo 17O-MRI
at 3 Tesla Using a TxRx Surface Coil
Jens Groebner1, Robert Borowiak1,2,
Manuela Rösler3, Reiner Umathum3,
Elmar Fischer1, John M. Pavlina1,
and Michael Bock1
1Dept. of Radiology / Medical Physics,
University Medical Center Freiburg, Freiburg, BW,
Germany, 2Deutsches
Konsortium für translationale Krebsforschung (DKTK),
German Cancer Research Center (DKFZ), Heidelberg, BW,
Germany, 3Dept.
of Medical Physics in Radiology, German Cancer Research
Center (DKFZ), Heidelberg, BW, Germany
Oxygen-17 (17O) MRI allows quantifying the
metabolic turnover of oxygen in
vivo. In this preliminary work a TxRx surface coil
was constructed for direct 17O
MRI at 3 Tesla. MR images of a phantom and a volunteer
were acquired at 3T for the first time. An SNR of 45 in
vitro and 50 in vivo could be achieved in clinically
acceptable acquisition times of less than 15 min at
in-plane resolutions between 5 and 12 mm.
|
|
1986. |
Redox Map of Mouse Brain by
Three-Dimensional EPR Imaging with Six-Membered Nitroxyl
Radicals
Miho C. Emoto1, Hideo Sato-Akaba2,
Hiroshi Hirata3, and Hirotada G. Fujii1
1Center for Medical Education, Sapporo
Medical University, Sapporo, Hokkaido, Japan, 2Department
of Systems Innovation, Osaka Universivy, Toyonaka,
Osaka, Japan,3Division of Bioengineering and
Bioinformatics, Hokkaido University, Sapporo, Hokkaido,
Japan
Six-membered nitroxides such as TEMPOL and TEMPONE are
redox-sensitive probes for redox research, but due to
their short lifetime in vivo, they have not been fully
examined in EPR imaging studies in living animals. In
this study, an improved EPR imaging system with a
rapid-field scanning capability was used, and
three-dimensional EPR images of mouse heads were
obtained after administration of TEMPOL and TEMPONE.
Half-life maps of TEMPOL and TEMPONE in mouse heads were
calculated from a series of EPR images recorded at an
interval of 16 s. Obtained half-life maps clearly
indicate the redox status of the mouse brain.
|
|
1987. |
Brain Redox Mapping in
Methamphetamine-Treated Mice Using Three-Dimensional EPR
Imaging
Hirotada G. Fujii1, Miho C. Emoto1,
Mayumi Yamato2, and Ken-ichi Yamada2
1Center for Medical Education, Sapporo
Medical University, Sapporo, Hokkiado, Japan, 2Faculty
of Pharmaceutical Sciences, Kyushu University, Fukuoka,
Fukuoka, Japan
Methamphetamine (METH)-induced neurotoxicity is
associated with mitochondrial dysfunction and enhanced
oxidative stress. The aims of the present study were to
examine the redox status in the METH-treated mouse brain
using the redox-sensitive imaging probe
3-methoxycarbonyl-2,2,5,5-tetramethyl-piperidine-1-oxyl
(MCP), and to noninvasively visualize brain redox status
with a three-dimensional electron paramagnetic resonance
(EPR) imaging system. Half-life mapping of
blood-brain-barrier-permeable MCP in METH-treated mice
was obtained from a series of temporal EPR images of
mouse heads at an interval of 20 s. The obtained
half-life map of MCP clearly visualized the effect of
METH treatment on the redox status in the mouse brain.
|
|
1988. |
Electron Paramagnetic
Resonance Spectrometry and Imaging in Melanomas: A
Comparison Between Pigmented and Non-Pigmented Human
Malignant Melanomas.
Quentin Godechal1, Ghanem Ghanem2,
Martin Cook3, and Bernard Gallez1
1Biomedical Magnetic Resonance, University of
Louvain, Brussels, Belgium, 2Universite
libre de Bruxelles, Brussels, Belgium, 3Department
of Histopathology, Royal Surrey County Hospital,
Guildford, United Kingdom
In this study, we proposed to use EPR imaging as a tool
to map the concentration of melanin inside ex-vivo human
pigmented and non-pigmented melanomas and to correlate
this cartography with anatomo-pathology. The importance
of the pigmentation for EPR measurement was
unambiguously demonstrated. Moreover, EPR images
accurately reflected the distribution of melanin
pigments within melanoma samples.
|
|
1989. |
Principal Component
Analysis Enhanced Dynamic Electron Paramagnetic Resonance
Imaging of Cycling Hypoxia in
vivo
Gage Redler1, Boris Epel1, and
Howard J. Halpern1
1Radiation and Cellular Oncology, University
of Chicago, Chicago, IL, United States
Hypoxia in tumors affects their malignant state and
resistance to therapy. These effects may be more
deleterious in regions undergoing cycling hypoxia.
Electron paramagnetic resonance imaging (EPRI) has
provided a non-invasive, quantitative imaging modality
to investigate static pO2 in vivo. However, to image
cycling hypoxia, better temporal resolution may be
required. The tradeoff between temporal resolution and
SNR results in lower SNR for EPRI images with higher
temporal resolution. Principal component analysis is
presented as a spatiotemporal filter via low-order
approximation of EPRI projection data, allowing studies
with SNR and temporal resolution necessary to study
cycling hypoxia in vivo.
|
|
1990. |
Sodium Triple-Quantum
Coherence Characterization of Scaffolds Used in Cartilage
Tissue Engineering
Mrignayani Kotecha1, Allen Ye1,
and Richard L. Magin1
1Bioengieering, University of Illinois at
Chicago, Chicago, IL, United States
Magnetic resonance characterization of engineered
cartilage tissue using sodium triple quantum coherence
spectroscopy (or imaging) is relatively new concept.
Chondrocytes seeded in alginate beads, Scaffold free
chondrocyte pellets and human mesenchymal stem cells
seeded in ECM integrated collagen/chitosan based
scaffolds were studied for four weeks post-cell seeding.
We found that the sodium biexponential relaxation
pathway of these tissue engineered constructs depends
upon the scaffold properties, cell density and tissue
microstructure. These finding suggests that sodium MRI
can play an important role in understanding the tissue
growth dynamics in cartilage tissue engineering.
|
|
1991. |
Does Li Displace
Intracellular Na in Brain?: An In
Vivo 23Na
MRI Study
Richard A. Komoroski1, Diana M. Lindquist2,
and John M. Pearce2
1Center for Imaging Research, University of
Cincinnati, Cincinnati, OH, United States, 2Imaging
Research Center, Cincinnati Children's Hospital Medical
Center, Cincinnati, OH, United States
Elevated intracellular Na, possibly arising from
abnormal Na,K-ATPase, has been proposed in bipolar
disorder. Lithium is often an effective treatment for
bipolar disorder. Sodium-23 MRI was used to follow the
effect of an IP dose of Li on intracellular Na in normal
rat brain in
vivo. For brain parenchyma, 23Na
MRI intensity increased by a maximum of 6.78% at 1.4 hrs
after Li injection and then fell slightly over the next
two hours. Sodium-23 T2s generally lengthened
with time, consistent with intra- to extracellular
movement of Na. The results are interpreted as
displacement of intracellular Na by Li.
|
|
1992. |
Biexponentially Weighted
Sodium Imaging with Higher SNR Efficiency
Nadia Benkhedah1, Peter Bachert1,
and Armin M. Nagel1
1Dpt. Medical Physics in Radiology, German
Cancer Research Center (DKFZ), Heidelberg, Germany
In this study a new method for generating
biexponentially weighted sodium images is presented.
Only two instead of three RF pulses are required for
filtering the signal. Images show an up to 3 times
improved SNR compared to conventional triple quantum
filtered (TQF) images with the same measurement
parameters. Measurement time can be shortened with the
new sequence design by reducing the number of averages
(only two instead of six are required) or by reducing TR
(as SAR is only about 2/3 of that of TQF sequences)
resulting in better SNR efficiency.
|
|
1993. |
Triple-Quantum Filtered
Chlorine Magnetic Resonance Imaging of the Human Brain
Alina Gilles1, Nadia Benkhedah1,
Peter Bachert1, Wolfhard Semmler1,
and Armin M. Nagel1
1Dpt. of Medical Physics in Radiology, German
Cancer Research Center (DKFZ), Heidelberg, Germany
In this study we present the first in vivo TQF 35Cl
images. MRI of TQF 35Cl
suffers from low sensitivity due to low gyromagnetic
ratio of 35Cl,
fast relaxation and low intracellular concentration.
However, for high fields (B0 =
7 T) acquisition of TQF 35Cl
images is possible. Selective detection of 35Cl
nuclei which are exposed to quadrupolar interaction,
i.e. intracellular 35Cl,
is thus feasible. Future monitoring of TQF 35Cl
signal may prove worthwhile in understanding the
pathophysiological changes of ion concentration in
various diseases including those of the central nervous
system (e.g. ischemia and tumors).
|
|
1994. |
Evaluation of Lactate
Detection Using Selective Multiple Quantum Coherence in
Phantoms and Brain Tumours
Lisa Maria Harris1, Nina Tunariu2,
Toni Wallace1, Nandita M. deSouza1,
Martin O. Leach1, and Geoffrey Payne1
1Institute of Cancer Research and Royal
Marsden Hospital, Sutton, Surrey, United Kingdom, 2Institute
of Cancer Research and Royal Marsden Hospital, Institute
of Cancer Research and Royal Marsden Hospital, Sutton,
Surrey, United Kingdom
A study using a selective homonuclear multiple quantum
coherence transfer transfer (SelMQC) sequence to
accurately quantify lactate by suppressing lipid signals
is presented. Phantom studies are shown to verify both
the lipid suppression and the lactate detection and the
performance of the sequence was assessed in brain
tumours where the presence of lactate and lipids are
both expected.
|
|
1995. |
Single Use Flexible
Resonant Loops for L-Band Tooth EPR
Selaka Bandara Bulumulla1, Daniel Lewek1,
Christopher Kapusta1, David Davenport1,
Joseph Iannotti1, Dmitriy Tipikin2,
Benjamin Williams2, and Harold Swartz2
1GE Global Research, Niskayuna, NY, United
States, 2Geisel
School of Medicine, Hanover, NH, United States
EPR can be used to estimate exposed radiation dose by
measuring the amount of free radicals in the crystalline
structure of the tooth enamel. In this work, we consider
a potentially detachable, flexible resonant loop as a
sensing probe. The flexible loop is conformal for a
better fit to patient dependent variable incisor teeth
geometries. Furthermore, this single use resonant loop
eliminates the need for cleaning between subjects and
increases the throughput by allowing the placement of
the resonant loop prior to positioning the subject in
the magnet. The loops can be fabricated using high
volume, lower cost manufacturing methods.
|
|
|
TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
1996.
|
Measurement of Metabolite 1H
Transverse Relaxation Times (T2) in the Human
Visual Cortex Over an Extended Echo-Time Range During Visual
Stimulation at 7T
Francesca Branzoli1, Ece Ercan1,
Andrew Webb1, and Itamar Ronen1
1C.J. Gorter Center for High Field MRI,
Department of Radiology, Leiden University Medical
Center, Leiden, Netherlands
In this work we employed a method we recently developed
for collection and analysis of multi-echo highly
truncated MRS CPMG (Carr-Purrell Meiboom-Gill)
spectroscopic data in order to achieve accurate proton
transverse relaxation times (T2) measurements of total
creatine (tCr), total NAA (tNAA) and choline compounds (tCho)
in the primary visual cortex at 7T and to investigate
possible T2 changes during visual stimulation. The large
echo-time range employed allowed for evaluation of
deviation of amplitude-TE curves from mono-exponential
decay pattern, reflecting the presence of
multi-components possessing different T2, as expected
for the tCr signal at 3.0 ppm.
|
1997.
|
Measurement of Transverse
Relaxation Times in Brain Tumors
Akshay Madan1, Sandeep Ganji1,
Elizabeth A. Maher2, and Changho Choi3
1Advanced Imaging Research Center, UT
Southwestern Medical Center, Dallas, Texas, United
States, 2Harold
C. Simmons Cancer Center, UT Southwestern Medical
Center, Dallas, Texas, United States, 3Advanced
Imaging Research Center, University of Texas
Southwestern Medical Center, Dallas, Texas, United
States
In this study we performed invivo T2 measurement
of metabolites like N-acetylaspartate, Creatine, Choline
and water in glioma patients for comparison with normal
brain using single voxel point resolved spectroscopy at
multiple echo times at 3T. We calculated T2 using
monoexponential nonlinear fitting of metabolite signal
estimates obtained from LCModel.
|
|
1998. |
129Xe-RBC T1 Dependence on
Blood Oxygen Saturation
Graham Norquay1, General Leung1,
Jan Wolber2, Gillian M. Tozer1,
and Jim M. Wild1
1University of Sheffield, Sheffield, South
Yorkshire, United Kingdom, 2GE
Healthcare, Amersham, Buckinghamshire, United Kingdom
In this study, the T1 of hyperpolarised (HP) 129Xe in
red blood cells (RBCs) was measured in vitro as a
function of blood saturation (sO2) on a 1.5T scanner.
129Xe-RBC T1 was found to increase linearly with
increasing sO2, where the mechanism believed to be
responsible for the 129Xe-RBC T1 sO2 dependence is
interactions of 129Xe nuclei with varying concentrations
of paramagnetic deoxyhaemoglobin. The observed linearity
between 129Xe-RBC T1 and sO2 has positive preclinical
and clinical implications, as it may open up the
possibility of using HP 129Xe in vivo as a non-invasive
quantitative probe for blood oxygenation in tumours.
|
|
1999. |
Measurement of the T1 Of 31P-Metabolites
at 7 Tesla in the Human Heart
Matthew D. Robson1, Stefan Neubauer1,
and Christopher T. Rodgers1
1OCMR, Oxford University, Oxford,
Oxfordshire, United Kingdom
Measurement of high-energy metabolite concentrations in
the heart offers insight and understanding of myocardial
disease and may yield unique diagnostic information. A
novel Look-Locker Inversion Recovery Chemical Shift
Imaging sequence was developed for evaluation of 31P
T 1 in-vivo.
Validation of this method on skeletal muscle agrees with
previous work. In 5 healthy males, the measured cardiac
T 1s were: PCr=2.81±0.47s,  -ATP=1.86±0.15s,  -ATP=1.34±0.09s,
and  -ATP=0.98±0.15s.
This reduction in T 1compared to lower fields
is consistent with work in skeletal muscle. CK flux has
a significant influence over the apparent T 1 of
PCr and -ATP.
|
|
2000. |
Preliminary 23Na Transverse
Relaxation Time Investigation Using a Continuous
Distribution Model
Frank Riemer1, Bhavana S. Solanky1,
Claudia Angela M. Wheeler-Kingshott1, and
Xavier Golay2
1NMR Research Unit, Queen Square MS Centre,
Department of Neuroinflammation, UCL Institute of
Neurology, London, United Kingdom, 2Department
of Brain Repair & Rehabilitation, University College
London, London, United Kingdom
Preliminary results from using a continuous distribution
model (regularized inverse Laplace transform) to analyse
23Na-T2* in the brain.
|
|
2001. |
Spin-Lattice and Spin-Spin
Relaxation of Water and Lipids in Human Vastus Lateralis M.
Measured by 1H-MRS at 3T
Sunil K. Valaparla1,2, Geoffrey D. Clarke2,
and Timothy O. Duong2,3
1Research Imaging Institute, University of
Texas Health Science Center San Antonio, San Antonio,
Texas, United States, 2Radiology,
University of Texas Health Science Center San Antonio,
San Antonio, Texas, United States, 3Research
Imaging Institute, UT Health Science Center at San
Antonio, San Antonio, Texas, United States
Quantitative evaluation of relaxation times can be used
to measure metabolite concentrations accurately and for
optimizing measurement protocols in single-voxel proton
magnetic resonance spectroscopy (1H-MRS). This study
reports spin-lattice and spin-spin relaxation times of
water, intra and extra-myocellular lipids in the human
vastus lateralis (VL) muscle obtained using a STEAM
single voxel pulse sequence in normal healthy subjects
at 3T. The results obtained are consistent with data
reported for 1.5T in VL and other muscles at higher
field strengths. These data can be applied to relaxation
corrections for the absolute quantification of vastus
lateralis m. lipid spectra in normal and diseased
states.
|
|
|
TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
Methodology of Spectroscopic Localization & Imaging
2002.
|
Simultaneous In
Vivo 1H
and 31P
MRS Acquisition in Ischemic Rat Brain at Ultrahigh Field
Jennifer M. Taylor1,2, Xiao-Hong Zhu2,
Yi Zhang2, and Wei Chen1,2
1Biomedical Engineering, University of
Minnesota, Minneapolis, MN, United States, 2Center
for Magnetic Resonance Research, Department of
Radiology, University of Minnesota, Minneapolis, MN,
United States
The information gained from a single MR spectroscopy (MRS)
scan using conventional acquisition strategies is
limited by the inability to acquire signal from multiple
nuclei simultaneously. We propose a new MR acquisition
configuration to allow for simultaneous acquisition of
localized spin echo 1H
and global single pulse 31P
MRS. We show this technique’s feasibility for monitoring
the alteration in cerebral metabolic and hemodynamic
activities during an acute global forebrain ischemia in
rat. This technique increases single measurement
information and allows the exploration of the dynamic
relationship among various metabolic and/or hemodynamic
activities in animal or human under different
physiopathological conditions.
|
2003.
|
in vivo Localized
Correlated Spectroscopy Using Spectral Spatial Coherence
Transfers
Galen D. Reed1, Trey Jalbert1,
Gerd Melkus1, Simon Hu1, Peder E.Z.
Larson1, Sarah J. Nelson1, John
Kurhanewicz1, and Daniel B. Vigneron1
1Radiology and Biomedical Imaging, University
of California San Francisco, San Francisco, CA, United
States
A localized correlated spectroscopy sequence using
spectral spatial coeherence transfer / water suppression
pulses is presented. High bandwidth and low peak power
was achieved by phase modulation of the spectral filter
and using phase-matched refocusing pulses. Insensitivity
to transmitter power offsets is demonstrated in phantoms
and compared to correlated spectroscopy acquired using
selective presaturation. Preliminary data from vounteers
indicate robust water suppression without cross peak
degredation due to water contamination.
|
|
2004. |
Accelerated 3D-Localized
Echo Planar Correlated Spectroscopic Imaging of Calf Muscle
Using Compressed Sensing
Neil E. Wilson1, Brian L. Burns2,
and M. Albert Thomas1
1University of California, Los Angeles, CA,
United States, 2UCLA,
Los Angeles, CA, United States
In one dimensional (1D) spectroscopy, there is no
information clearly linking J-coupled partners as there
is with 2D localized correlated spectroscopy (L-COSY),
which also produces much less crowded spectra. Recently,
an echo planar spectroscopic imaging readout was added
to L-COSY to collect a 4D data slice in (kx, ky, t2, t1)
space (EP-COSI). Showing the potential for scan time
reductions, NUS was retrospectively applied on the
incrementally-acquired (ky, t1) plane. Here, we extend
EP-COSI to a 3rd spatial dimension collecting data in (kx,
ky, kz, t2, t1) and apply NUS prospectively on the (ky,
kz, t1) volume.
|
|
2005. |
Separation and Precise
Estimation of Glutamate and Glutamine Using Spectroscopic
Imaging in Human Brain at 3.0 T
Sandeep Ganji1 and
Changho Choi2
1Advanced Imaging Research Center, UT
Southwestern Medical Center, Dallas, Texas, United
States, 2Advanced
Imaging Research Center, University of Texas
Southwestern Medical Center, Dallas, Texas, United
States
We report in vivo spectroscopic imaging of glutamate and
glutamine at 3T using an optimized echo-time PRESS-based
localization method. Using our technique we achieved
separation of Glu (2.35 ppm) and Gln (2.45 ppm) signals.
The Gln concentration showed significant regional
variation over the brain, with higher levels in gray
matter dominant regions compared to white matter
dominant regions. Higher concentrations of
N-Acetylaspartylglutamic acid (NAAG) were well
correlated with white matter dominant regions.
Scan/rescan were performed in six healthy volunteers and
reproducibility results are presented.
|
|
2006. |
Sensitivity Decomposition
of Water and Metabolites with Sensitivity Encoding for
Reducing Scan Time
Toru Shirai1, Satoshi Hirata1, Yo
Taniguchi1, Yoshihisa Soutome1,
and Yoshitaka Bito2
1Hitachi, Ltd., Central Research Laboratory,
Kokubunji, Tokyo, Japan, 2Hitachi,
Ltd., Kokubunji, Tokyo, Japan
We propose a method that combines the sensitivity
decomposition method with the sensitivity encoding
method for simultaneously acquiring water and
metabolites signals to reduce the scan time. This method
consists of a measurement that shifts only the water
signal on an image and undersamples in k-space, and a
data process that separates each signal by using the
coil sensitivities. The results of experiments with a
healthy volunteer showed that the proposed method
reduced the scan time to one-fourth of the fully sampled
CSI, to which non-water-suppressed measurement was
added.
|
|
2007. |
Inherent Reduction of
Residual Lipid Aliasing in SENSE-Accelerated 1H
MRSI at 7T by Spatially Selective SRF Optimization
Thomas Kirchner1, Lukas Eisenring1,
Klaas P. Pruessmann1, and Anke Henning1,2
1Institute for Biomedical Engineering,
University and ETH Zurich, Zurich, Switzerland, 2Max
Planck Institute for Biological Cybernetics, Tuebingen,
Germany
As a consequence of voxel bleeding and residual spatial
aliasing in SENSE-accelerated in vivo 1H
MRSI, lipid signal originating in the skull region is
often found in spectroscopic imaging voxels in the
brain. To a certain extent, those artifacts can be
contained by target-driven overdiscretized
reconstruction with direct optimization of the Spatial
Response Function (SRF) compared to conventional SENSE
with Hamming filtering. In this work, we demonstrate
that an even better spectral quality can be achieved by
exploiting spatial prior knowledge to specify spatially
selective priority for SRF optimality.
|
|
2008. |
Proton Observed Phosphor
Editing (POPE) Brings Hope for in
vivo Detection
of Phospholipid Metabolites
Dennis W. J. Klomp1, Robin A. de Graaf1,2,
Christine Nabuurs3, Irene M.L. van Kalleveen1,
Wybe J.M. van der Kemp1, Peter R. Luijten1,
Hermien E. Kan4, Andrew Webb4,
Jannie P. Wijnen1,4, and Vincent Oltman Boer5
1UMC Utrecht, Utrecht, Utrecht, Netherlands, 2Yale
University, New Haven, CT, United States, 3Maastricht
University, Maastricht, Limburg, Netherlands, 4Leiden
UMC, Leiden, Holland, Netherlands, 5University
Medical Center Utrecht, Utrecht, Utrecht, Netherlands
Phospholipids are highly valuable biomarkers, but
detection sensitivity requires substantial optimization.
Although conventional in vivo 1H
MRS cannot discriminate these phosphomono and diesters, 31P
MRS can, but lacks sensitivity. Here we present that
using 31P
selective editing pulses in a 1H
MRS experiment, sensitivity can be boosted by a factor
of 2.8 compared to SNR optimized 31P
MRS while still enabling distinct detection of
phospho-choline (PC), -ethanolamine (PE) and their
glycerol compounds (GPC and GPE). Validated in the human
brain at 7T, these biomarkers can be explored in
clinical studies.
|
|
2009. |
The Effect of Compressed
Sensing Reconstruction on the Spatial Resolution of Magnetic
Resonance Spectroscopic Imaging.
Lara Angharod Worthington1,2, Martin Wilson2,3,
Theodoros N. Arvanitis2,4, Andrew C. Peet2,3,
and Nigel Paul Davies3,5
1PSIBS, University of Birmingham, Birmingham,
West Midlands, United Kingdom, 2Birmingham
Children's Hospital NHS Foundation Trust, Birmingham,
West Midlands, United Kingdom, 3Cancer
Sciences, University of Birmingham, Birmingham, West
Midlands, United Kingdom, 4School
of Electronic, Electrical & Computer Engineering,
University of Birmingham, Birmingham, West Midlands,
United Kingdom, 5Imaging
& Medical Physics, University Hospital Birmingham NHS
Foundation Trust, Birmingham, West Midlands, United
Kingdom
Current clinical Magnetic Resonance Spectroscopic
Imaging (MRSI) is limited by long acquisition times and
poor spatial resolution. Compressed sensing has been
suggested as a possible speed up technique, but the
effect of this and other k-space under-sampling
techniques on the quality of MRSI spatial resolution is
so far unknown. This study developed a novel methodology
to assess the spatial resolution in MRSI after
reconstruction using compressed sensing and compared
this to an equivalently sampled dataset at the center of
k-space in phantom and volunteer datasets. This
technique showed that compressed sensing maybe preferred
in situations where acquisition speed and high spatial
resolution is of importance.
|
|
2010. |
Nonuniformly Undersampled
5D (3 Spatial + 2 Spectral) Echo Planar J-Resolved
Spectroscopic Imaging of Brain
Neil E. Wilson1, Brian L. Burns2,
and M. Albert Thomas1
1University of California, Los Angeles, CA,
United States, 2UCLA,
Los Angeles, CA, United States
J-resolved spectroscopy is a multidimensional technique
to enhance spectral information by pushing multiplet
splittings into a second dimension. EP-JRESI combines
localized J-resolved spectroscopy with an echo planar
readout for a single slice acquisition. Here, we extend
EP-JRESI to include a 3D localization and use nonuniform
sampling (NUS) and compressed sensing (CS) on the
incrementally-acquired volume (ky, kz, t1) to achieve
far greater accelerations in scan time.
|
|
2011. |
1H-MRS in the in
Vivo Mouse
Heart: A Comparison Between PRESS and STEAM
Adrianus J. Bakermans1, Desiree Abdurrachim1,
Klaas Nicolay1, and Jeanine J. Prompers1
1Biomedical NMR, Eindhoven University of
Technology, Eindhoven, Netherlands
Proton MR spectroscopy (1H-MRS) allows for
the noninvasive detection of myocardial metabolites, but
its application in preclinical studies has been limited.
We assessed the suitability of PRESS and STEAM for 1H-MRS
in the in
vivo mouse
heart. Both sequences were ECG-triggered and
respiratory-gated. To maintain steady state of
magnetization, dummy pulses were performed during
respiratory gates. Water signal stability was slightly
better for PRESS than for STEAM, and SNR for PRESS was
two-fold higher compared to STEAM. Using PRESS-localized
saturation recovery experiments, T1 values
were determined for mouse myocardial water and
triglyceride.
|
|
2012. |
Application of Parallel
Imaging and Compressed Sensing to Metabolic Imaging of the
Brain Using H-1 MRSI at 7T and Using Hyperpolarized C-13
MRSI at 3T
Maryam Vareth1,2, Yan Li1, Ilwoo
Park1, and Sarah Nelson1,3
1Surbeck Laboratory of Advanced Imaging,
Department of Radiology and Biomedical Imaging, Univ. of
California, San Francisco, San Francisco, CA, United
States,2UCSF/UCBerkeley Joint Graduate Group
in Bioengineering, Univ. of California, Berkeley,
Berkeley, CA, United States, 3Department
of Bioengineering and Therapeutic Sciences, Univ. of
California, San Francisco, San Francisco, CA, United
States
We developled and tested the feasibility of using
parallel imaging (PI) and compressed sensing (CS)
techniques to reconstruct phase-sensitive MRSI data for
both hyperopoarzied 3T C-13 and 7T H-1 applications that
require efficient and rapid k-space sampling.
Self-calibrating techniques such as GRAPPA, SPIRiT were
implemented for use in spectroscopy in addition to CS,
to inintially investigate the most roubst and accurate
estimation of fully sampled data. Results indicated that
these methods effectively reconstructed the data.
|
|
2013. |
31P-Spectroscopy on Humans
at 9.4 T in Combination with a Patch Antenna for Proton
Imaging: Initial Results
Morteza Bakhtiary1, Gunamony Shajan1,
Jens Hoffmann1, Klaus Scheffler1,2,
and Rolf Pohmann1
1Max Planck Institute for Biological
Cybernetics, Tübingen, BW, Germany, 2Department
for Biomedical Magnetic Resonance, University of
Tübingen, Tübingen, BW, Germany
Due to its low sensitivity, 31P spectroscopy can gain
particularly from ultra high field strength. To
demonstrate the potential of 31P in 9.4 T human
applications, spectra from the calf and the brain of
human subjects were acquired, using either a surface or
a birdcage coil for phosphorus transmission and
reception, combined with a proton traveling wave antenna
for localization and shimming. First results show
promising SNR and spectral quality.
|
|
2014. |
Editing Magnetic Resonance
Spectroscopy of Lactate at High Fields: Improved Efficiency
by Inclusion of FOCI Pulses and Elimination of Co-Edited
Macromolecules
Jannie P. Wijnen1, Catalina S. Arteaga de
Castro1, Vincent Oltman Boer2,
Anna Andreychenko1, Peter R. Luijten1,
Bas Neggers3, and Dennis W.J. Klomp1
1Radiology, University Medical Centre
Utrecht, Utrecht, Utrecht, Netherlands, 2Radiology,
University Medical Center Utrecht, Utrecht, Utrecht,
Netherlands, 3Psychiatry,
University Medical Centre Utrecht, Utrecht, Utrecht,
Netherlands
The weakly coupled spin system of low concentrated
lactate can be measured with MRS editing techniques.
Obtaining this at the potentially high sensitivity of
high field strength can be challenging due to the low
available B1+ field resulting in narrow bandwidth
refocusing pulses and therefore in large chemical shift
displacement errors (CSDE). Frequency offset corrected
inversion (FOCI) pulses substantially increase the
bandwidth of adiabatic pulses and are used in this study
in a MEGA-sLASER editing sequence for highly efficient
measurements of lactate. Combined with nulling of
co-edited macromolecules, we demonstrate that artefact
free lactate signals can be detected in the human brain
at 7T.
|
|
2015. |
Magnetic Resonance
Spectroscopy Based Temperature Calibration and in-vivo Brain
Temperature Measurement of Traumatic Brain Injury Rats at 7
Tesla
Sankar Seramani1, Bhanu Prakash K.N.1,
Sanjay K. Verma1, Kian Chye Ng2,
Enci Mary Kan2, Gopalan V.1,
Michael N.1, Yaligar J1, Graham S.3,
Jia Lu2, C. Childs4, and Sendhil
S. Velan1,5
1Laboratory of Molecular Imaging, Singapore
Bioimaging Consortium, Singapore, Singapore, 2Defence
Medical and Environmental Research Institute, DSO
National Laboratories, Singapore, Singapore, 3Department
of Psychology, National University of Singapore,
Singapore, Singapore, 4Yong
Loo Lin School of Medicine, National University of
Singapore, Singapore, Singapore, 5Clinical
Imaging Research Centre, Agency for Science, Technology
and Research, Singapore, Singapore
Magnetic resonance spectroscopy based non-invasive
temperature measurement of an in-vivo brain is one of
the most preferred ways of mapping the temperature of
the brain. This is based on the relationship between
water resonant frequency of the tissue and the actual
temperature of the tissue. Hence, it is necessary to
calibrate/derive the relationship between the chemical
shift of the water and the temperature, by using the
brain metabolites phantom for the given field strength
of the magnet. Traumatic Brain Injuries (TBI) causes
increase in brain temperature due to inflammation and
other neuroprotective mechanism. Monitoring the region
specific brain temperature in-vivo helps in predicting
the prognosis of the treatment in the TBI subjects. We
calibrated the in-house designed brain metabolite
phantom at different temperatures on a 7 Tesla scanner
and also explored the changes in brain temperature of
TBI rats at different time-points. The water chemical
shift showed a linear dependence on temperature in the
phantom calibration and increased brain temperature was
observed in TBI rats until Day-3, which decreased
subsequently.
|
|
2016. |
Improved Volume
Localization for MRSI at 7T Using RF Shimming and RF
Multiplexing
Hoby P. Hetherington1, Nikolai I. Avdievich1,
and Jullie Pan1
1Neurosurgery, Yale University, New Haven,
CT, United States
At 7T, increased spectral dispersion and decreased B1
results in increased spectral dispersion artifacts when
using slice or slab selective pulses. Recent
developments of RF shimming based localization using
“ring” distributions generated solely by RF shimming
eliminate spectral dispersion artifacts. However, with
only 8 independent RF coils/RF channels, the ring
distribution can reduce SNR for the neocortical
periphery. In this work we describe an improved RF
shimming based localization method using a 16 coil
transceiver array and RF multiplexing to dramatically
improve the selectivity of the ring distribution and
preserve SNR for MRSI in the cortical periphery.
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|
2017. |
Accelerated Phosphorus MR
Spectroscopic Imaging of Human Brain Using Compressed
Sensing
Gokce H. Hatay1, Cagil Gumus1,
Bahattin Hakyemez2, and Esin Ozturk-Isik3
1Electrical and Electronics Engineering,
Yeditepe University, Istanbul, Turkey, 2Department
of Radiology, Uludag University, Bursa, Turkey, 3Biomedical
Engineering, Yeditepe University, Istanbul, Turkey
This study aims at assessing compressed sensing
reconstruction for faster phosphorus MR spectroscopic
imaging (31P MRSI) of human brain. A 31P MRSI dataset
containing a tumor region and a healthy region was
created based on the metabolite peak intensities of a
volunteer dataset acquired at 3T. k-space data was
randomly undersampled while preserving the cental
portion for a reduction factor of 1.6, and reconstructed
using compressed sensing. This study showed that
compressed sensing reconstruction could be applied for
faster 31P MR spectroscopic imaging, and its performance
will be assessed in brain tumors.
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|
2018. |
2D-GRAPPA Accelerated FID
Based MRSI of the Brain at 7T
Bernhard Strasser1, Gilbert Hangel1,
Stephan Gruber1, Siegfried Trattnig1,
and Wolfgang Bogner1,2
1Department of Radiology, Medical University
of Vienna, Vienna, Vienna, Austria, 2Department
of Radiology, Athinoula A. Martinos Center for
Biomedical Imaging, Boston, Massachusetts, United States
In this work the excess signal-to-noise ratio per unit
time that was provided by the use of measuring with an
FID based sequence at 7T, and performing an optimized
coil combination was traded for a substantial reduction
in scan time, thus, enabling high resolution MRSI
measurements in clinical relevant times. This trade-off
was achieved by using optimized 2D-GRAPPA acceleration.
The acquisition times were reduced to below four minutes
with a spectral quality that is comparable to that of a
more than eight times longer measurement with a volume
coil. Five volunteers were measured to prove the
feasibility of the method.
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|
2019. |
MRS Sparse-FFT: Reducing
Acquisition Time and Artifacts for in
vivo 2D
Correlation Spectroscopy
Lixin Shi1, Ovidiu C. Andronesi2,
Haitham Hassanieh1, Badih Ghazi1,
Dina Katabi1, and Elfar Adalsteinsson1,3
1Electrical Engineering and Computer Science
Department, Massachusetts Institute of Technology,
Cambridge, MA, United States, 2Martinos
Center for Biomedical Imaging, Radiology Department,
Massachusetts General Hospital, Harvard Medical School,
Boston, MA, United States, 3Harvard-MIT
Division of Health Sciences and Technology, Cambridge,
MA, United States
In-vivo localized 2D Correlation Spectroscopy (COSY)
enables detection of new molecular biomarkers of
disease. The challenges for this method are, however,
long acquisition times and truncation artifacts along
the f1 frequency dimension that may obscure the
cross-diagonal peaks. We propose to address these
challenges by adapting the recently developed sparse-FFT
algorithms, which optimize reconstruction of sparse
signals in the Fourier domain. Our preliminary results
demonstrate that sparse-FFT can reduce measurement time
of 2D COSY by almost a factor of three, eliminates t1
truncation artifacts resulting from the ringing tails of
the diagonal peaks, and improves SNR and resolution of
cross-peaks.
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2020. |
Implementation of
GOIA-Wurst(16,4) Pulses in the Semi-LASER Sequence for
SAR-Reduction in Prostate MRSI
Isabell K. Steinseifer1, Marnix C. Maas1,
Thiele Kobus1, Tom W.J. Scheenen1,
and Arend Heerschap1
1Radiology, Radboud University Nijmegen
Medical Centre, Nijmegen, Gelderland, Netherlands
We present 1H
MRSI of the prostate achieved with the semi-LASER
sequence and GOIA-WURST(16,4) refocusing pulses to
reduce specific absorption rates. This can lead to
reduced repetition times and improved k-space weighting
to optimize SNR and acquisition times. In particular it
may allow 1H MRSI with the use of an endorectal coil
with increased spatial resolution within clinically
acceptable scan times. The GOIA-W(16,4) pulses used in
this work had a higher bandwidth than the standard
higher order Hyperbolic Secant pulses (8.5kHz instead of
3.2 kHz) used in the semi-LASER sequence.
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2021. |
Group-Mean Template
Modelling of NAA- And NAAG-Edited MR Spectra
Nicolaas A. J. Puts1,2, Mona M. Mohamed1,
Peter B. Barker1,2, and Richard Anthony
Edward Edden1,2
1The Russell H. Morgan Department of
Radiology and Radiological Science, Johns Hopkins
University, Baltimore, Maryland, United States, 2FM
Kirby Centre for functional neuroimaging, Kennedy
Krieger Institute, Baltimore, Maryland, United States
NAA and NAAG can be seperated in vivo using edited MRS.
Our previous study used rough methods to analyse
spectra, and the creation of basis sets is problematic.
Here we shows that a template-based fitting model based
on the group-mean of the data is suitable for fitting
NAA and NAAG.
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2022. |
3D Metabolic Mapping of the
Brain at 7T by Pulse-Cascaded Hadamard Encoding with Short
Acquisition Delay
Gilbert Hangel1, Bernhard Strasser1,
Stephan Gruber1, Marek Chmelik1,
Siegfried Trattnig1, and Wolfgang Bogner1,2
1MR Centre of Excellence, Medical University
of Vienna, Vienna, Vienna, Austria, 2Athinoula
A. Martinos Center for Biomedical Imaging, Department of
Radiology, Massachusetts General Hospital, Harvard
Medical School, Boston, MA, United States
This work compares metabolic maps of pulse-cascaded
four-slice Hadamard Spectroscopic Imaging (HSI) with
short acquisition delay to standard single slice 2D-CSI
at 7T. HSI overcomes point-spread function problems in
slice encoding direction and enables the measurement of
few slices with high in-plane resolution in acceptable
measurement time making full use of the high SNR at 7T.
Pulse cascading reduces B1 requirements, specific
absorption rates, and chemical shift displacement
errors. The short acquisition delay maximizes SNR and
avoids J-coupling effects. Measurements in eight
volunteers show the good comparability of metabolic maps
between HSI and CSI as well as the Hadamard-specific SNR-increase.
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2023. |
Metabolic Imaging with 3D
Echo Planar Spectroscopic Imaging at 7 Tesla
Sankar Seramani1, Yevgen Marchenko1,
Sanjay K. Verma1, Bhanu Prakash K.N.1,
Navin Michael1, Suresh Anand Sadananthan1,
Andrew A. Maudsley2, and Sendhil S. Velan1,3
1Laborartory of Molecular Imaging, Singapore
Bioimaging Consortium, Singapore, Singapore, Singapore, 2Miller
School of Medicine, University of Miami, Miami, Florida,
United States, 3Clinical
Imaging Research Centre, Agency for Science, Technology
and Research, Singapore, Singapore
3D Echo Planar Spectroscopic Imaging (EPSI) is one of
the promising fast spectroscopic imaging techniques to
map the regional metabolite concentrations within
clinically feasible time. Whole brain distributions of
NAA, tCr, and tCho and its ratios can be measured using
the 3D EPSI. We have implemented a 3D EPSI sequence on a
7T MRI/MRS scanner and demonstrated it in a phantom with
a voxel resolution of 2mm3 and on a rat brain. Regional
metabolite distributions of NAA, Creatine & Choline and
its ratios were computed using MIDAS Software. The
feasibiility of mapping whole brain NAA, Cr, Cho
concentrations is demonstrated from the rat brain.
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2024. |
Automated Spectral
Assessment of the BOLD Effect for Neurofeedback at 3 and 7
T.
Yury Koush1,2, Mark A. Elliott3,
Frank Scharnowski1,2, and Klaus Mathiak4,5
1Department of Radiology and Medical
Informatics - CIBM, University of Geneva, Geneva,
Switzerland, 2Institute
of Bioengineering, École Polytechnique Fédérale de
Lausanne, Lausanne, Switzerland, 3Center
for Magnetic Resonance and Optical Imaging (CMROI),
Department of Radiology, University of Pennsylvania,
Philadelphia, Pennsylvania, United States, 4Department
of Psychiatry, Psychotherapy and Psychosomatics, RWTH
Aachen University, Aachen, Germany, 5Institute
of Neuroscience and Medicine (INM-1), Research Center
Jülich, JARA - Translational Brain Medicine, Aachen,
Germany
To date, conventional echo planar imaging (EPI) based
fMRI is the only method capable of providing real-time
neurofeedback from a spatially specific ROI. Our
research provides evidence that localized functional
single-voxel proton spectroscopy (fSVPS) can be used as
an alternative approach. We automatized and evaluated
this new approach by running real-time fSVPS experiments
on high (3 T) and ultra-high (7 T) magnetic fields.
Overall, real-time water SVPS neurofeedback is a
promising tool for studying and manipulating brain
activity, which holds great promise for important
scientific and clinical applications.
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2025. |
Gradient Induced Sideband
Artifacts in Non Water-Suppressed Proton CSI of the Human
Brain at 9.4 T
Grzegorz L. Chadzynski1,2, Rolf Pohmann2,
Gunamony Shajan2, Rupert Kolb3,
Uwe Klose3, and Klaus Scheffler1,2
1Dept. Biomedical Magnetic Resonance,
University Hospital Tuebingen, Tuebingen, Germany, 2Dept.
High-Field Magnetic Resonance, Max Planc Institute for
Biological Cybernetics, Tuebingen, Germany, 3Dept.
Neuroradiology, University Hospital Tuebingen,
Tuebingen, Germany
CSI without water suppression offers several advantages,
like the possibility to use the water signal for
absolute quantification. However, the unsuppressed
spectra are hampered by gradient induced sidebands,
which have to be removed before the quantification.
Despite known difficulties (shorter T2 relaxation time,
larger B0 and B1 inhomogeneities), previous studies
demonstrated that CSI at ultra-high magnetic field is
feasible. The aim of this study was to verify the
feasibility of short TE proton CSI on the human brain
without water suppression at the field strength of 9.4 T
and to examine the influence of sidebands on the
measured spectra.
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2026. |
MEGA-PRESSing Onward for
More Metabolites: Aspartate, Lactate, and PE
James B. Murdoch1, Andrew J. Wheaton1,
and Robert Anderson1
1Toshiba Medical Research Institute USA,
Mayfield Village, Ohio, United States
With a change in the edit-ON selective inversion
frequency to 3.89 ppm, the TE 80 MEGA-PRESS sequence
favored for GABA editing can be used to highlight
aspartate as well. Inverting the aspartate CH proton on
half the acquisitions and taking the difference between
edit-ON and edit-OFF shots yields a peak at 2.74 ppm
from J-coupled aspartate CH2 spins. Other metabolites of
interest with J-coupled resonances near 3.89 ppm are
co-edited – including lactate and phosphorylethanolamine
(PE). Posterior cingulate cortex (PCC) spectra from a
normal volunteer were phase and frequency aligned on a
shot-by-shot basis and processed with LCModel.
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2027. |
Slice Selective Adiabatic
Pulse for Human 31P
Cardiac Spectroscopy
William T. Clarke1, Christopher T. Rodgers1,
Stefan Neubauer1, and Matthew D. Robson1
1OCMR, University of Oxford, Oxford, United
Kingdom
3D 31P
chemical shift imaging (CSI) suffers from long scan
times even at relatively low resolution. A slice
selective adiabatic pulse (ASSESS) was implemented for
2D 31P
CSI. The pulse is not affected by chemical shift, is B1 insensitive
and produces an arbitrary flip angle. Simulations were
used to choose optimal parameters and experimental
setup. The pulse implementation was successfully
demonstrated in phantoms. Short in vivo sequences were
run on two volunteers at 3T. The spectra produced
comparable SNR to the 3D method, all peaks expected were
observed.
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2028. |
Real-Time Single-Voxel
Water Proton Spectroscopy and Echo-Planar Imaging
Sensitivity to the BOLD Effect at 3 and 7 T.
Yury Koush1,2, Mark A. Elliott3,
Frank Scharnowski1,2, and Klaus Mathiak4,5
1Department of Radiology and Medical
Informatics - CIBM, University of Geneva, Geneva,
Switzerland, 2Institute
of Bioengineering, École Polytechnique Fédérale de
Lausanne, Lausanne, Switzerland, 3Center
for Magnetic Resonance and Optical Imaging (CMROI),
Department of Radiology, University of Pennsylvania,
Philadelphia, Pennsylvania, United States, 4Department
of Psychiatry, Psychotherapy and Psychosomatics, RWTH
Aachen University, Aachen, Germany, 5Institute
of Neuroscience and Medicine (INM-1), Research Center
Jülich, JARA - Translational Brain Medicine, Aachen,
Germany
It has been shown that spin-echo single-voxel proton
spectroscopy (SVPS) can be used for spatially specific
BOLD neurofeedback at 7 T. However, it is not clear how
neurofeedback based on SVPS compares to the more
commonly used gradient-echo echo-planar imaging (EPI)
based neurofeedback. We showed that the data quality of
real-time SVPS and EPI are comparable at 3 T. At 7 T,
the real-time SVPS does not reach the quality of EPI and
needs to be further improved. However, the 7 T spin-echo
acquisition might target specifically microvascular
contributions to the BOLD effect and benefit from
increased spatial resolution.
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2029. |
Real-Time Motion Correction
and B0 Shim Update for a Spectral Edited MEGA-LASER Sequence
Ovidiu C. Andronesi1, Aaron T. Hess2,
Matthew Dylan Tisdall1, Wolfgang Bogner1,
André J. W. van der Kouwe1, and Bruce R.
Rosen1
1Martinos Center, Radiology, Massachusetts
General Hospital, Charlestown, Massachusetts, United
States, 2Centre
for Clinical Magnetic Resonance, John Radcliffe
Hospital, University of Oxford, Oxford, Oxford, United
Kingdom
J-difference spectral editing sequences such are
necessary to detect important neurotransmitters and
brain metabolites such as GABA, glutamate,
2-hydroxyglutarate, and glutathione which are otherwise
obscured by more stronger signals. However, difference
methods are susceptible to subtraction artifacts caused
by subject movement, while the performance of narrow
band MEGA pulses may be affected by drifts in the B0
field and shims. These challenges are likely to happen
because editing requires long measurement times. Here we
show that by acquiring in each TR an EPI volume
navigator of the whole head prior to MEGA-LASER
excitation we can perform real-time correction of motion
in human subjects and update the shims and scanner
frequency.
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|
TRADITIONAL
POSTER SESSION • MR SPECTROSCOPY
Thursday, 25 April 2013 (10:30-12:30) Exhibition Hall |
Methodology of Spectroscopic Quantitation
|
2030. |
Enhancement of
2-Hydroxyglutarate Detectability by Triple-Refocusing
Difference Editing at 3T in
vivo
Changho Choi1, Sandeep Ganji2,
Akshay Madan1, Robert Bachoo1,
Ralph DeBerardinis1, and Elizabeth A. Maher1
1University of Texas Southwestern Medical
Center, Dallas, Texas, United States, 2UT
Southwestern Medical Center, Dallas, Texas, United
States
Given the great potential of 2HG as a biomarker in the
diagnosis and management of glioma patients as well as
the workup of an undiagnosed mass, the capability of
precise detection of 2HG in vivo is extensively needed.
In 1H-MRS, the 2HG signals are severely overlapped with
other metabolite signals. Specifically, because of the
close proximity of the 2HG 2.25 ppm resonance to the
GABA 2.29 ppm resonance, when the 2HG levels are
relatively low, 2HG estimation is elusive. Here we
present 2HG measurements without considerable GABA
contamination in patients in vivo, achieved by
constant-TE triple-refocusing difference editing at 3T.
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2031. |
Accelerating 2D-JPRESS in
the Human Brain with Compressed Sensing
Trina Kok1, Navin Michael2, and
Sendhil S. Velan1,3
1A*STAR-NUS Clinical Imaging Research Center,
Singapore, Singapore, 2Singapore
Institute for Clinical Sciences, Singapore, Singapore, 3Singapore
Bioimaging Consortium, Singapore, Singapore
Detection of metabolite signals are often hampered by
spectral overlap arising from J-coupling effects.
Existing techniques for improved separation include 2D
spectroscopy methods such as 2DPRESS, which carries a
penalty in scan-time and is often prohibitive when
combined with spectroscopic imaging. In this work, we
apply compressed sensing to a randomly under-sampled
data set, collecting 30 t1 increments of the original
100 t1 increments. The reconstructed 2D spectrum is
subsequently fitted with ProFit and we show that
metabolites were recovered with reasonable CRLB values,
with 30% of the original data.
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2032. |
Extraction of Glutamate
from the GABA Edited Spectra
Jan Willem C. van der Veen1, Ron de Beer2,
Dirk van Ormondt2, and Jun Shen1
1Magnetic Resonance Spectroscopy Core, NIH,
NIMH, Bethesda, Maryland, United States, 2Department
of Applied Physics, TU Delft, Delft, Netherlands
It is desirable to simultaneously measure glutamate and
GABA in many clinical studies. Here we used full density
matrix simulation to investigate the effects of GABA
editing on the J evolution of glutamate, glutamine and
NAA at 3 Tesla. It was found the editing pulse and
spectra subtraction significantly reduced overlap of
glutamate by glutamine and NAA, making it possible to
extract glutamate using linear combination spectral
fitting of the edited GABA spectra.
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2033. |
Partial Volume Correction
Method for Improving Test-Retest Repeatability of In
Vivo Human
Brain 1H
MRS and Quantification of Neurochemical Concentrations at 7T
Byeong-Yeul Lee1, Xiao-Hong Zhu1,
Wei Chen1, and Melissa Terpstra1
1Center for Magnetic Resonance Research (CMRR),
Radiology Department, University of Minnesota,
Minneapolis, MN, United States
Human brain ultra-high field (7T) scanners are
increasingly available in clinical settings and
advantageous for sensitivity and specificity. Accurate
quantification of metabolite concentrations from 1H MRS
requires appropriate partial volume correction,
especially when studying treatment effect or pathologies
that alter brain morphometry. We developed a tissue
segmentation method that remained reliable in the
presence of inhomogeneous B1, which is typically
encountered at ultra-high field. Utilization of T1/PD
ratio images improved histogram based classification of
tissue types. Using this approach to correct for partial
volume effects, test-retest repeatability of metabolite
concentrations quantified from single voxel in vivo
1H-MRS was improved.
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2034. |
Investigation of Techniques
for Multi Element Coil Combination for 32 Channel 7T MRS
Emma Louise Hall1, Mary C. Stephenson1,
Darren Price1, and Peter G. Morris1
1Sir Peter Mansfield Magnetic Resonance
Centre, University of Nottingham, Nottingam,
Nottinghamshire, United Kingdom
In magnetic resonance spectroscopy (MRS), the
acquisition of data from multi-element receive coils is
becoming common. As the number of coil elements
increases the need arises for robust reconstruction
methods. Here we compare three methods based on signal
or signal and noise weighting. We demonstrate this on
for proton MRS data acquired using a 32 channel receive
coil at 7 Tesla acquired in different brain regions. We
find that the visual cortex benefitted the most, whereas
medial prefrontal cortex was relatively unaffected.
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2035. |
High-Resolution Localized
2D J-Resolved Spectroscopy Via Intermolecular Single-Quantum
Coherences
Yuqing Huang1, Zhiyong Zhang1,
Shuhui Cai1, and Zhong Chen1
1Department of Electronic Science, Xiamen
University, Xiamen, Fujian, China
Localized 2D J-resolved spectroscopy can separate
chemical shifts and J couplings into two different
dimensions. It is widely used for the detection of
metabolites in biological tissues, even in in vivo
study. However, due to the intrinsic magnetic
susceptibility in biological tissues, the localized 2D
J-resolved spectrum is usually suffered from field
inhomogeneity. In this report, a new pulse sequence
based on intermolecular single-quantum coherences is
presented to obtain localized 2D J-resolved spectrum in
inhomogeneous fields, which is potentially useful for
studying biological metabolites.
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2036. |
Removal of Lipid Nuisance
Signals in MRSI Using a Spatial-Spectral Lipid Model
Chao Ma1,2, Fan Lam1,2, Ryan
Larsen2, Bradley P. Sutton2,3, and
Zhi-Pei Liang1,2
1Department of Electrical and Computer
Engineering, University of Illinois at Urbana-Champaign,
Urbana, IL, United States, 2Beckman
Institute, University of Illinois at Urbana-Champaign,
Urbana, IL, United States, 3Department
of Bioengineering, University of Illinois at
Urbana-Champaign, Urbana, IL, United States
Nuisance lipid signals from the subcutaneous lipid layer
of the brain often cause significant difficulties for
spectral quantification of the brain metabolites.
Removal of the lipid signals in brain MRSI is desirable
but challenging because they appear as multiple-peak,
broad spectra that overlap with the spectra of important
brain metabolites (e.g., lactate and NAA). In this work,
we introduce a model-based post-processing method for
effective removal of the lipid signals.
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2037. |
An Alternate Strategy
for the Quantification of the in
Vivo Glutamate/Glutamine
(Glx) Peak at 2.35 Ppm
Ravi Prakash Reddy Nanga1, Hari Hariharan1,
and Ravinder Reddy1
1Radiology, University of Pennsylvania,
Philadelphia, Pennsylvania, United States
Quantification of in
vivo Glutamate/Glutamine
(Glx) peak at 2.35 ppm from 1H
MRS is contaminated with NAA, lipids, macromolecule and
with Glx peak at 2.13 ppm. This contamination introduces
a challenge in Glx quantification. Here, we propose and
demonstrate an alternate strategy to quantify the Glx at
2.35 ppm with high reproducibility, in
vivo.
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2038. |
Localization Profile
Correction for ERETIC Based in Vivo 1H
MRSI Quantification
Niklaus Zoelch1, Alexander Fuchs1,
and Anke Henning2,3
1Institue for Biomedical Engineering, UZH and
ETH Zurich, Zurich, Switzerland, 2Institue
for Biomedical Engineering, University and ETH Zurich,
Zurich, Switzerland, 3Max
Planck Institue for Biological Cybernetics, Tübingen,
Germany
ERETIC is a calibration method independent of the
disease state, automatically compensates for changes in
coil loading conditions and hence requires only a one
time calibration against a high precision phantom.
However, when ERETIC is used for the quantification of
MRSI images, the combined effect of B1+ inhomogeneity
across the volume of interest and slice profiles of the
selective RF pulses used for localization need to be
corrected for. In this work two approaches of this
correction are presented and validated against internal
water referencing.
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2039. |
in vivo Transverse
Relaxation Time Measurements from Localized CT-COSY and
JPRESS: A Validation Study
Dimitri Martel1, Tangi Roussel1,
Denis Friboulet1, Denis Grenier1,
and Helene Ratiney1
1CREATIS ; CNRS UMR5220 ; Inserm U1044 ; INSA-Lyon
; Université Lyon 1, Villeurbanne, France
Transverse relaxation time parameters (T2 and T2inh due
to field inhomogeneity) of the three main singlets of
NAA, Creatine and Choline in the rat hippocampus were
measured at 7T using two 2D MRS sequences (Localized CT-COSY
and JPRESS). Estimated T2inh with this approach compared
with its direct measurements using a B0 field map show
good agreement. T2 found by this method show lower
values than expected. Diffusion loss due to the Hahn
echo type of the sequences used is suspected.
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2040. |
Clinical MRS Data
Processing Using KBDM
Fernando Fernandes Paiva1, Alberto Tannus1,
and Claudio Jose Magon1
1Institute of Physics of Sao Carlos,
University of Sao Paulo, Sao Carlos, SP, Brazil
KBDM is a parametric non-linear method that can be
applied for fitting and spectral analysis of
experimentally measured transient time signals and is a
promising tool that can provide complimentary
information to the well-established FT techniques. In
the present study we investigate the feasibility of
clinical MRS data processing using KBDM, with special
attention to important issues such as signal-to-noise
ratio and baseline distortions. The accuracy of the
method for spectral analysis for both simulated and in
vivo data
is reported.
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2041. |
Gannet: GABA Analysis
Toolkit for Edited MRS
Richard Anthony Edward Edden1,2, Nicolaas A.
J. Puts2,3, Peter B. Barker1,2,
and C. John Evans4
1Russell H. Morgan Department of Radiology
and Radiological Science, Johns Hopkins University,
Baltimore, MD, United States, 2F.
M. Kirby Center for Functional Brain Imaging, Kennedy
Krieger Institute, Baltimore, Maryland, United States, 3Russell
H. Morgan Department of Radiology and Radiological
Science, The Johns Hopkins University School of
Medicine, Baltimore, MD, United States, 4CUBRIC,
School of Psychology, Cardiff University, Cardiff,
Wales, United Kingdom
Gannet
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|
2042. |
Simultaneous Detection of
17 Brain Metabolites at 3T by JPRESS & ProFit
Alexander Fuchs1, Peter Boesiger1,
and Anke Henning1,2
1Institute for Biomedical Engineering,
University and ETH Zurich, Zurich, Zurich, Switzerland, 2Max
Plank Institute for Biological Cybernetics, Tübingen,
Germany
In-vivo data acquired at 3T and simulated 2D JRPESS
spectra were used to test and validate the new version
of the ProFit fitting tool. The results indicate the
potential to reliable fit up to 17 brain metabolites
with CRLBs below 20%.
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|
2043. |
Maximum Entropy
Reconstruction of Non-Uniformly Under-Sampled
Multidimensional Spectroscopic Imaging in
vivo
Brian L. Burns1, Neil Wilson2, and
M. Albert Thomas2,3
1Department of Biomedical Engineering, UCLA,
Los Angeles, CA, United States, 2Biomedical
Physics IDP, UCLA, Los Angeles, CA, United States, 3Radiology,
UCLA, Los Angeles, CA, United States
This work accelerates the acquisition of 4D MRSI data (2
spectral x 2 spatial) by under-sampling a spatial and a
spectral dimension and reconstructing the missing data
using Maximum Entropy (MaxEnt) non-linear
reconstruction. Our results show that non-uniform
under-sampling combined with MaxEnt is a viable way to
reduce the scan times required of 4D MRSI to a
clinically acceptable 6 minutes.
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