ISMRM 25th Annual Meeting & Exhibition • 22-27 April 2017 • Honolulu, HI, USA

Electronic Poster Session: MR Spectroscopy
 5465 -5488 MRS Processing 5489 -5512 MRS Acquisition Methods 5513 -5536 MRSI Methods 5585 -5608 NMR & ESR & Education 5609 -5632 Non-Proton MRI & MRS 5633 -5655 MRS Applications

MRS Processing
Electronic Poster
MR Spectroscopy

Thursday, 27 April 2017
 Exhibition Hall 13:00 - 14:00

MRS Acquisition Methods
Electronic Poster
MR Spectroscopy

Thursday, 27 April 2017
 Exhibition Hall 13:00 - 14:00

MRSI Methods
Electronic Poster
MR Spectroscopy

Thursday, 27 April 2017
 Exhibition Hall 13:00 - 14:00

 Computer # 5520. 80 Comparison of different acceleration methods for high-resolution metabolite mapping using 1H FID MRSI at 9.4T Sahar Nassirpour, Paul Chang, Anke Henning Reliable metabolite mapping of the human brain using ultra-short TE and TR 1H FID-MRSI is possible at ultra-high fields. However, MRSI studies with high spatial resolutions and brain coverage suffer from long scan times. To make these studies clinically relevant, different acceleration methods are used at the price of losing SNR. The aim of this study is to implement and compare different in-plane acceleration methods: SENSE, GRAPPA and compressed sensing for high-resolution metabolite mapping of the human brain at 9.4T without lipid suppression. 5518. 78 Macromolecule Mapping with Ultrashort-TE Acquisition and Metabolite Spectral Prior Fan Lam, Yudu Li, Bryan Clifford, Zhi-Pei Liang This work presents a novel method for macromolecule mapping and quantification. The proposed method integrates an FID-based MRSI acquisition with a generalized series (GS) model based extrapolation scheme. The FID acquisition allows for the use of ultrashort echoes and short repetition times for fast imaging with improved SNR efficiency. The GS model effectively makes use of the spectral priors from single voxel spectroscopy and allows for reformulating the back-extrapolation of metabolite signals as a linear problem (in contrast to conventional nonlinear methods). Results from in vivo experiments demonstrate that MM signals estimated by the proposed method are consistent with an inversion recovery based method and lead to better metabolite quantification. 5519. 79 Covariance Five Dimensional Echo Planar J-resolved Spectroscopic Imaging Zohaib Iqbal, M. Albert Thomas Chemical shift imaging is a very important method used to investigate several pathologies in vivo. A recent technological development incorporating an echo planar readout, a non-uniform sampling scheme, and an iterative, non-linear reconstruction is the five dimensional echo planar J-resolved spectroscopic imaging (5D EP-JRESI) method. While this technique is capable of obtaining 3 spatial and 2 spectral dimensions in vivo, the indirect spectral dimension has a low spectral resolution, which may hinder accurate metabolite quantitation. In this study, a novel approach using a covariance transformation after reconstruction is assessed and compared to the 5D EP-JRESI method. 5530. 90 A Minimum-Phase Shinnar-Le Roux Spectral-Spatial Excitation RF Pulse for Water and Lipid Suppression in 1H MRSI of Body Extremities Kexin Deng, Chao Ma, Kui Ying, Georges El Fakhri It is challenging to remove nuisance water and lipid signals in 1H-MRSI of body extremities. Strong lipid signals exist both in the subcutaneous layer and bone marrow but also in the muscle, i.e., intramyocellular and extramyocellular lipids.  This work presents a novel minimum-phase Shinnar-Le Roux (SLR) spectral-spatial excitation RF pulse for both water and lipid suppression in 1H-MRSI of body extremities. We have validated the proposed method using Bloch equation simulation, phantom, and in vivo studies. 5532. 92 Spatial Hadamard encoding of J-edited spectroscopy using slice-selective editing pulses Kimberly Chan, Georg Oeltzschner, Michael Schär, Peter Barker, Richard Edden A new approach for simultaneous dual-voxel J-difference spectral editing is described, that uses spatially selective spectral-editing pulses and Hadamard encoding. The theoretical framework for Spatial Hadamard Editing and Reconstruction for Parallel Acquisition (SHERPA) was developed, applying gradient pulses during the frequency selective editing pulses. SHERPA was simulated for GABA, tested in a two-compartment GABA phantom, and applied to the left and right hemispheres of ten normal subjects. SHERPA was successfully implemented with results in close agreement with conventional MEGA-PRESS scans.  Compared to conventional single-voxel single-metabolite J-difference editing, two-fold acceleration is possible without significant loss of SNR using the SHERPA method. 5528. 88 Motion Correction for 1H-MRSI of the Brain Using Unsuppressed Water Signals Bryan Clifford, Xi Peng, Yudu Li, Zhi-Pei Liang, Fan Lam Head motion poses a significant problem in MRSI experiments, especially for 1H-MRSI of the brain performed without water or lipid suppression. In this work we propose a practical method specifically designed to track head motion and correct for its effects on 1H-MRSI data acquired without water suppression. By using the companion spectroscopic water signals, we are able to track head motion with navigators collected in circular and linear trajectories. A specialized data processing scheme is also proposed for processing the navigator data along with the unsuppressed spectroscopic water signals to determine the motion parameters. 5514. 74 semi-adiabatic SPECIAL-based 1H MRSI at 9.4T: Implementation and preliminary validation in a rat brain Hyeong-Hun Lee, Hyeonjin Kim Given the issues of chemical shift displacement error, B1 inhomogeneity and short T2 at high field, a semi-adiabatic SPECIAL-based MRSI sequence was implemented at 9.4T, which is equipped with a pair of broad-band hyperbolic secant adiabatic full passage pulses for refocusing, and yet, allows a minimum TE of as short as 4.98 ms. In phantom, the effect of the prolonged minimum TE on the J-evolution of coupled spins is negligible. In a rat brain, preliminary quantitative results are in close agreement with the previous results obtained by using single-voxel MRS. 5515. 75 High resolution MRSI using compartmental low rank algorithm: demonstration using undersampled EPSI Ipshita Bhattacharya, Ralph Noeske, Baolin Yang, Rolf Schulte, Mathews Jacob Improved spatial resolution is the need of the hour for MRSI. In this work we propose an algorithm which provides a comprehensive and automatic approach to recover high resolution metabolite maps from highly undersampled acquisitions; the improved spatial resolution translates to improved spectral quality and reduced leakage artifacts. The proposed algorithm is also quite flexible and can be readily used in a variety of sequences, including EPSI, CSI, and spirals acquisition schemes. 5513. 73 S-ESPIRiT: Estimation of Coil Sensitivity Maps from MR Spectroscopic Imaging Data Using ESPIRiT Namgyun Lee, Vincent Boer, Esben Petersen, Gyunggoo Cho Estimating a set of coil sensitivity maps that is consistent with the low-resolution SENSE model is challenging in SENSE spectroscopic imaging. Recently, ESPIRiT, an autocalibrating approach to estimate sensitivity maps for MR imaging, that combines both advantages of SENSE and GRAPPA has been developed. In this work, we propose a spectroscopic extension of ESPIRiT, referred to as S-ESPIRiT, to estimate sensitivity maps from Cartesian 2D spectroscopic k-space data.  The proposed method was demonstrated using 2D spectroscopic imaging data of a brain metabolite phantom acquired with a semi-LASER pulse sequence and a 32-channel receive head coil on a 7T MRI scanner. 5523. 83 Full-field of view GM and WM spectroscopy in vivo using spatial lipid pattern estimation and BASE-SLIM localization - permission withheld Peter Adany, In-Young Choi, Phil Lee The presence lipids of several orders of magnitude higher concentrations than metabolites in the extracranial tissues present significant challenges for the reliable acquisition and quantification of 1H MRSI, especially in the outer perimeter areas of the brain.  We developed a novel spatial lipid reconstruction technique to remove nuisance lipid signals in 1H MRS. We applied lipid reconstruction to MRSI data and performed BASE-SLIM localization on the lipid-subtracted signal. Using this method, high quality compartment spectra of GM and WM could be obtained. 5516. 76 Evaluation of Compressed Sensing reconstructions of 3D Echo Planar Spectroscopic Imaging using TV, Wavelet-$$\ell_{1}$$$, and TV+Wavelet-$$\ell_{1}$$$ based regularization. Andres Saucedo, Zohaib Iqbal, Manoj Sarma, M. Albert Thomas Magnetic Resonance Spectroscopic Imaging (MRSI) is a valuable tool to characterize metabolic concentrations and changes in several spatial locations in a single recording. However, the long acquisition time of conventional three-dimensional (3D) MRSI limits its practical application. Non-uniformly sampled 3D echo planar spectroscopic imaging (EPSI) has been proposed to accelerate the scan time, combined with compressed sensing (CS) to retain reconstruction fidelity.  We apply the novel approach of reconstructing 3D EPSI data by applying TV, Wavelet-$$\ell_{1}$$$, and TV + Wavelet-$$\ell_{1}$$$ CS-based regularization on both the combined spectral and two undersampled spatial dimensions. These three reconstruction methods were evaluated in both simulated and in retrospectively undersampled data of a brain phantom. 5517. 77 Low-Rank TGV Reconstruction of High-Resolution 1H-FID-MRSI of whole brain slices Antoine Klauser, Dimitri Van De Ville, Franc¸ois Lazeyras High resolution MRSI data were acquired with 2D FID-MRSI at 3T and a post-processing including lipid suppression, low-rank approximation and TGV-reconstruction is proposed. The resulting metabolic images of tNAA, tCre, Cho, Ins and Glx showed a substantial gain in quality, CRLB values associated and the SNR. This effect was particularly marked for lower signal metabolite: Ins and Glx. In addition, the proposed post-processing reconstructed efficiently under-sampled data allowing a 2- or 4-fold acquisition acceleration. 5525. 85 IRREGULAR SPIRAL ACQUISITION FOR COMPRESSIVE SENSING IN MRSI Jabrane Karkouri, Fabien Millioz, Magalie Viallon, Rémy Prost, Hélène Ratiney Magnetic resonance spectroscopic imaging (MRSI) has multiple interests in clinical practice but it faces quite long acquisition time in practice which limits their use in a clinical environment. In this work, a new fast Magnetic Resonance Spectroscopic image acquisition method, based on Compressed Sensing and the a priori known support of the metabolites chemical shift, is introduced and evaluated based on a k-t space spiral sampling.  In the real-world noisy scenario the error in the recovered spectrum highly depends on the acquired samples. We reduce this error to an acceptable level by selecting irregularly the samples using the Sequential Backward Selection algorithm. Our method has been applied on an in vivo 31P acquisition, to prove the feasibility of the proposed approach. 5524. 84 Multi-region Semi-Adiabatic Spectral-Spatial Spectroscopic Imaging (SASSI) sequence for accelerated MRSI at 7T Rebecca Feldman, Priti Balchandani High field MRI permits us to leverage increased signal-to-noise ratio (SNR) and spectral separation between metabolite peaks for more sensitive metabolite detection at higher spatial resolutions. However, the acquisition of high-resolution spectral grids can be prohibitively time intensive. Accelerated MRSI acquisitions are challenged by the limitations at 7T. We develop a multi-region SPSP excitation pulse and use it to create a novel low power, B1 insensitive multi-region SASSI sequence with minimal chemical shift to enable accelerated MRSI. 5527. 87 Rigid Motion Correction in MRSI Using Wireless Active Markers Yibo Zhao, Chao Ma, Chang Gao, Kui Ying, Jinsong Ouyang, Georges El Fakhri For brain imaging, even with head restraints, maximum translations in the range of 5-10 mm and rotations of 1-4 degrees are sometimes observed.  The rigid body motion of the subject during MRSI acquisition can degrade both the spatial resolution and spectral quality. In this work, we developed a wireless active marker based method to track and correct motion in MRSI. 5526. 86 Prospective frequency correction using outer volume suppression-localized navigator for MR Spectroscopic Imaging Chu-Yu Lee, In-Young Choi, Phil Lee Data acquisitions for magnetic resonance spectroscopic imaging (MRSI) require a long scan time to increase SNR and for spatial encoding. During the prolonged scan time, maintaining a constant static magnetic field (B0) is important for a robust MRSI measurement. However, frequency drifts occur over time even in advanced MR systems and become larger when high shim currents or rapidly switched gradients are applied. The frequency drift causes broad and distorted spectral lineshapes, reduced SNR, and quantification errors. These effects can be mitigated retrospectively and prospectively. However, in MRSI measurements, these effects can only be mitigated using the prospective frequency correction, because each spectrum is phase-encoded. The prospective frequency correction is typically achieved by incorporating a PRESS-based interleaved reference scan (PRESS-IRS) as a navigator, termed as PRESS-IRS navigator. A small excitation flip angle (10-20°) is used for the PRESS-IRS navigator to reduce the saturation-induced SNR loss on metabolite signals. Nonetheless, the SNR loss remains unavoidable and becomes notable when the imperfect refocusing pulses or a short repetition time (TR) are used in MRSI. In this study, a new prospective frequency correction method is introduced. The new method utilizes the outer volume suppression-localized navigator, termed OVS-localized navigator, resulting in no perturbations of metabolite signals and thus no saturation-induced SNR losses. Meanwhile, a precise measurement of the frequency drift and the effective correction is achieved. The presented method was demonstrated in two-dimensional (2-D) MRSI measurements under the large frequency drift induced by a fMRI experiment. 5521. 81 Density Weighted Concentric Circle Trajectories for Brain MRSI at 7T Lukas Hingerl, Bernhard Strasser, Philipp Moser, Gilbert Hangel, Siegfried Trattnig, Wolfgang Bogner A density weighted concentrically circular echo-planar trajectories readout scheme is presented for brain MRSI at 7 T. We give an analytic solution for the variable radii distribution in order to intrinsically measure a Hamming weighted k-space. A comparison with post acquisition filtered equidistant concentric circles is done. Invivo metabolic maps and spectra are shown. 5531. 91 High resolution cortical spectroscopy at 7T using lipid signal crushing and a high density receive array. Alex Bhogal, Carrie Wismans, Christiaan Vinckers, Peter Luijten, Dennis Klomp, Jannie Wijnen In this work we attempt to overcome MRSI limitations associated with extra-cranial lipid signal leakage and low SNR at high resolution. We use a dedicated crusher coil for lipid signal removal, in combination with a high density receive array and an  7T MR scanner for boosted SNR. 5522. 82 Metabolite-Cycling Short-Echo Time Magnetic Resonance Spectroscopic Imaging using a Concentric Ring k-space Trajectory Uzay Emir, Brian Burns, Mark Chiew, Peter Jezzard, Albert Thomas In this study, the feasibility of acquiring and quantifying short-echo (TE = 14 ms), two-dimensional (2D) STEAM MRSI spectra from the motor cortex was demonstrated by utilizing a non-water-suppressed metabolite-cycling technique. The increase in measurement time by the metabolite-cycling is counterbalanced by a time-efficient concentric ring k-space trajectory. High quality spectra were acquired from 36 localized 2mL voxels in 8 minutes. The metabolite spectra and estimated concentrations were in agreement between non-water-suppressed and water-suppressed MRSI techniques.  Findings of this study demonstrate that a non-water-suppressed metabolite-cycling MRSI technique can perform robustly on clinical MRI scanners and within a clinically feasible acquisition time. 5529. 89 Lipid Suppression in 3D Magnetic Resonance Spectroscopic Imaging Mohammed Goryawala, Andrew Maudsley, Sulaiman Sheriff Proton MR spectroscopic imaging (MRSI) is complicated by the presence of subcutaneous lipids, which, if not suppressed before Fourier reconstruction, cause ringing in metabolite maps due to limited k-space sampling. In this study inversion recovery (IR) based lipid suppressed acquisition was compared to non-lipid suppressed acquisition combined with two methods for reducing lipid ringing in whole brain MRS imaging. Results indicate non-lipid suppressed acquisition using the l2-regularization or Papoulis-Gerchberg algorithm for reconstruction is possible without significant ringing artifacts, however, can have a detrimental effect on spectral linewidth and baseline, resulting in smaller spatial coverage than IR based lipid-suppressed acquisition. 5536. 96 Accelerated 3D Echo Planar Spectroscopic Imaging of HIV: Metabolite Changes Correlation with CD4 count and Number of Years of Treatment Rajakumar Nagarajan, Eric Daar, Zohaib Iqbal, Manoj Sarma, Mario Guerrero, Michael Thomas In vivo proton magnetic resonance spectroscopy studies of HIV-infected humans have demonstrated region-specific changes in brain metabolites including N-acetylaspartate, creatine, choline, glutamate/ glutamine, and myo-inositol. Using a 3D EPSI technique, we examined metabolite ratios with respect to creatine in several regions of brain in 18 HIV adults (mean age 46.2 years) and 15 healthy controls (mean age 43.4 years). We have demonstrated for the first time the feasibility of a novel accelerated 3D EPSI method in HIV-infected adults compared to age matched healthy controls and correlated with CD4 counts and number of years of treatment. 5535. 95 Assessment of Neurochemical changes in HIV adults Using Accelerated MR Spectroscopic Imaging and Compressed Sensing Reconstruction Rajakumar Nagarajan, Eric Daar, Ebrahim Haroon, Zohaib Iqbal, Neil Wilson, Sathya Arumugam, Mario Guerrero, Michael Thomas In this work, we have successfully evaluated the accelerated 5D EP-JRESI sequence in 16 adult HIV-infected  patients and 15 healthy subjects. Compared to healthy subjects, significant neurochemical changes were observed in HIV+ patients on ART: elevated Ch/Cr ratios in frontal gray, right frontal white and right basal ganglia locations, decreased Glx ratios in the left frontal white, right basal ganglia, occipital gray and white and right insular cortical regions. There was also decreased NAA/Cr in the left basal ganglia and right occipital white regions. In the HIV+ patients, a positive correlation was recorded between the left basal ganglia NAA/Cr and the number of years of ART treatment (r=0.58, p<0.02). 5534. 94 Using 3D MEGA-LASER MRSI to study the role of basal ganglia GABA and Glx in response selection in Manganese neurotoxicology Ruoyun Ma, Sandy Snyder, Ann-Kathrin Stock, Wolfgang Bogner, Ovidiu Andronesi, Christian Beste, Ulrike Dydak This pilot study on manganese (Mn) neurotoxicity investigates the association between deficits in response selection and GABA and Glx levels in basal ganglia structures using MEGA-LASER 3D MRSI. Using a novel automated brain-structure-specific quantification approach for GABA+ and Glx, we studied three basal ganglia structures and the thalamus in Mn-exposed welders and controls. A modified Simon task was used to measure selection inhibition. GABA+ and Glx in putamen and globus pallidus were associated with response times in the most complicated experimental scenario in Mn-exposed subjects; whereas thalamic Glx levels were associated with response time for all subjects. 5533. 93 A Vendor-Agnostic MRSI Acquisition and Reconstruction XML Descriptor Format Marram Olson, Jason Crane, Peder Larson, Sarah Nelson The evaluation of MRSI data is complex because data files are encoded with vendor specific file formats and there is a lack of standardized tools for reconstruction. A standard way to describe raw MRSI data is necessary for the reconstruction of sequences utilizing parallel and non-Cartesian sampling strategies. In this work we are developing a vendor neutral data format to define MRSI sequences with arbitrary k-space trajectories that can be used by reconstruction software to understand the data acquisition scheme. This file format is XML-based and uses the ISMRMRD header as a basis for its scheme.

NMR & ESR & Education
Electronic Poster
MR Spectroscopy

Thursday, 27 April 2017
 Exhibition Hall 14:00 - 15:00

Non-Proton MRI & MRS
Electronic Poster
MR Spectroscopy

Thursday, 27 April 2017
 Exhibition Hall 14:00 - 15:00

MRS Applications
Electronic Poster
MR Spectroscopy

Thursday, 27 April 2017
 Exhibition Hall 14:00 - 15:00

 Computer # 5633. 73 Interregional associations between GABA+, Glx and BOLD contrast changes during acute pain perception in the human brain – A combined 1H fMRS and fMRI study Marianne Cleve, Alexander Gussew, Gerd Wagner, Jürgen Reichenbach Possible associations between BOLD and left insular GABA+/tCr and Glx/tCr levels were investigated by conducting whole brain fMRI measurements and 1H MEGA-PRESS MRS at 3 T in healthy subjects prior to and during acute pain stimulation. A significant negative correlation between insular resting state GABA+/tCr levels and BOLD response was obtained in the supplementary motor area with transition to the mid-cingulate cortex. Furthermore, insular ΔGlx revealed a significant positive association with BOLD signal in the left anterior and right posterior insula. These findings suggest interregional interrelations between metabolite levels and stimulus induced BOLD response in the pain processing network. 5634. 74 Abnormal developmental trajectories of brain metabolites contributed to abnormal muscle tone development in infants with prenatal methamphetamine and tobacco-exposure Linda Chang, Sara Hayama, Steven Buchthal, Chathura Siriwardhana, Daniel Alicata, Zachary Pang, Tricia Wright, Jon Skranes, Thomas Ernst In prior studies, children with prenatal methamphetamine-(PME) or tobacco-exposure (PTE) showed elevated brain metabolites levels.  The current study evaluated infants with PME and PTE during the first 5 months of life and found abnormal developmental trajectories of metabolites in the frontal white matter, with abnormally lower levels of total creatine [tCr], N-acetylaspartate [NAA], and glumate+glutamine [Glx] at baseline, and steeper developmental trajectories that resulted in normal or elevated levels after 2-months old. Furthermore, the trajectories of basal ganglia-[NAA] and corticospinal tract-[tCr] further contributed to the slower muscle tone development in PME infants, especially the males. 5635. 75 Neurochemical alterations in the hippocampus induced by high-fat diet: In vivo magnetic resonance spectroscopy - video not available Song-I Lim, Kyu-Ho Song, Chi-Hyeon Yoo, Dong-Choel Woo, Bo-Young Choe In this study, we investigated the neurochemical alterations in mouse hippocampus using in vivo proton magnetic resonance spectroscopy. We also examine the effect of high-fat diet on the levels of abdominal fat, plasma leptin, and corticosterone. The decrease in mIns concentration seen in HF diet mice without corresponding Gln-Glu alternation may reflect changes in glial function. In addition, the observed total choline levels indicate attenuated membrane turnover in HF diet mice. We therefore suggest that diets rich in saturated fats induce a stress-related response through metabolic disturbance and HPA axis dysfunction, which may indicate a relationship between obesity and depression. 5642. 82 In vivo measurement of metabolic changes associated with chick embryo development using 1H-NMR spectroscopy at 14.1 Tesla Antoine Cherix, Brodier Laurent, Jean-Marc Matter, Rolf Gruetter 1H-MRS was used to study the metabolic changes associated with development of the neural tissue in vivo longitudinally. Different tissues (yolk, eye and vitreous body) of developing chickembryos were scanned at three different stages (E3, E6 and E8) for metabolic quantification. As expected, results indicate that a critical juncture appears between stages E3 and E6 in terms of energetic status of the embryo. 5636. 76 Reliability of in vivo Glx measurements from GABA-edited MRS at 3T Elodie Boudes, Rachelle Loo, Kari Parsons, Gareth Barker, David Lythgoe, Richard Edden, R Marc Lebel, Martin Wilson, Ashley Harris Mixed glutamate/glutamine (GLX) signal contributes to spectra acquired for GABA editing, both as a co-edited peak in the difference spectrum and in the OFF subspectrum. GLX results are often included in GABA studies, but the reliability of these metrics has received little attention. In this study, we examine the relationship between GLX measures, using a short-TE PRESS as a “gold standard”, and comparing GLX measured from the co-edited peak and the OFF subspectrum from typical GABA+ and macromolecule-suppressed GABA acquisitions. 5637. 77 Prognostic utility of cervicovaginal fluid acetate-glutamate ratio for risk of preterm delivery within two weeks of presentation with symptoms of threatened preterm labour Emmanuel Amabebe, Steven Reynolds, Victoria Stern, Graham Stafford, Martyn Paley, Dilly Anumba Accurate identification of pregnant women with symptoms of preterm labor (PTL) most likely to deliver prematurely soon after presentation/assessment is crucial for prompt clinical decision making and allocation of scarce resources by minimizing unnecessary hospitalizations and treatments, as well as by triaging patients to the centers with optimal care facilities.  We determined the predictive capacity of cervicovaginal fluid (CVF) acetate/glutamate ratio in pregnant women presenting with symptoms of threatened PTL using 1H-NMR. The ratio of CVF acetate to glutamate demonstrated better prediction of delivery within 2 weeks of symptomatic presentation, compared to either acetate or glutamate alone. 5638. 78 Reproducibility for MRS-Based Relaxometry and Identification of Influential Parameters - permission withheld Bernhard Neumayer, Thomas Widek, Chris Boesch, Eva Scheurer The different relaxation times of the water and the fat compartment in human lumbar vertebrae make it necessary to determine these values for a correct calculation of the fat fraction, which is used as a biomarker for various applications. This study investigates the reproducibility of relaxometry in human lumbar vertebrae to serve as a basis for future studies. Furthermore, factors like age, sex, and physique are investigated for their influence on the derived T1 and T2 values to investigate whether relaxation times of the fat and water compartments can serve as biomarkers in addition to the fat fraction. 5639. 79 Mapping brain macromolecules in patients with multiple sclerosis using 1H-MRSI at 7T Michal Považan, Eva Heckova, Gilbert Hangel, Bernhard Strasser, Stephan Gruber, Assunta Dal-Bianco, Fritz Leutmezer, Siegfried Trattnig, Wolfgang Bogner Multiple sclerosis (MS) is a disease of the central nervous system associated with demyelination and glial activation affecting large areas of white matter. 1H-MRSI may detect the metabolic changes induced by MS and facilitate the differentiation between MS lesions. Our study aimed to detect and map the signal of macromolecules in healthy controls and MS patients. 2D FID-based 1H-MRSI was used with measurement time under 6 minutes. We found increased macromolecules in the perilesional region and decreased macromolecules in most of the lesions. However, in some lesions, macromolecules were increased, which may be possibly related to pathological activation of lesion. 5640. 80 Decreased tNAA concentration in female college basketball players with mild depression/anxiety symptoms Xian-Feng Shi, Perry Renshaw, Deborah Yurgelun-Todd The aim of the present study was to examine possible gender differences in 1H brain metabolite concentrations in male and female college basketball players. Decreased total N-acetylaspartate/N- acetylaspartylglutamate (tNAA) levels within white matter tissue were observed in female basketball players with symptoms of depression or anxiety (p = 0.0256 /p = 0.0112). 5641. 81 Cerebral Metabolite Changes and Cognitive Clinical Correlates in Perinatally HIV-infected Young Adults Manoj Sarma, Margaret Keller, Tamara Welikson, Sathya Arumugam , David Michalik, Irwin Walot, Karin Nielsen-Saines, Jaime Deville, Andrea Kovacs, Eva Operskalski, Joseph Ventura, M. Albert Thomas A recently implemented 5D echo-planar J-resolved spectroscopic sequence using 8x acceleration and compressed sensing reconstruction was evaluated in 7 perinatally infected and 8 healthy youths. Selected metabolite ratios with respect to Cr were detected bilaterally in the basal ganglia, anterior insular cortex, posterior insular cortex, frontal white and occipital/frontal gray regions of the two groups. Statistically significant differences were found between metabolite ratios (/Cr) of HIV-infected youing adults and healthy control subjects in the occipital gray N-acetylaspartate, right basal ganglia glutamine/glutamate, left anterior insular cortex choline, and left posterior insular cortex. Also, our pilot findings suggest a possible difference in energy metabolism between perinatally HIV-infected young adults and controls without HIV. The metabolite ratios correlated with neuropsychological test scores showing cognitive impairment as result of HIV-infection and/or long term ART. 5643. 83 Can we predict the chemotherapy outcomes and efficacy - metabolomics approach for predicting response to anticancer drugs: in vitro 1H MRS of living human melanoma and bladder carcinoma at 9.4T Katarzyna Pierzchala, Nicolas Kunz, Rolf Gruetter The number of patients diagnosed with cancer is increasing. Therefore the ability to predict tumor response to therapeutic agents remains a major challenge. Tumor cell metabolism is currently examined by 1H MRS with the aim of getting more insight into the differences between normal and neoplastic tissues, characterize their metastatic potential/finding prognostic markers, and monitoring the effect of therapies. In this study we demonstrate the feasibility of characterizing in-vitro living cells and present changes in the metabolic profile of WM793 and T24 cells lines subjected to chemotherapy. These results show promise for more personalized treatment protocols for cancer patients. 5644. 84 Improving the detection of scalar-coupled resonances at short and moderate echo times for in vivo rat MRS at 9.4 T - permission withheld Liangjie Lin, Yanqin Lin, Dan Tian, Hongyi Yang, Zhiliang Wei, Peter Barker, Kai Zhong, Zhong Chen Conventional localized 1H MRS pulse sequences, such as PRESS and STEAM, generally suffer from J coupling modulations which can aggravate attenuation of multiplet resonances during echo times. Here, the “perfect echo” module combined with an optimized localization scheme is utilized for in-phase single-voxel in vivo MRS at 9.4 T. The relative signal intensities of multiplet to singlet resonances acquired at short and moderate echo times increase substantially in comparison with those at PRESS spectra. Therefore, direct MRS quantification of many important metabolites, such as glutamine, glutamate, γ-aminobutyrate, aspartate, and myo-inositol, may be improved. 5645. 85 The subjective intensity of pain in healthy subjects is inversely correlate with posterior insular GABA levels Margot Thiaucourt, Polina Shabes, Natalie Schloss, Markus Sack, Ulf Baumgaertner, Christian Schmahl, Gabriele Ende We present single voxel MEGA-PRESS MRS data from the posterior insula of 20 healthy women demonstrating a significant association of GABA and the subjective pain thresholds. These findings are in good agreement with the postulated role of the posterior insula for pain information processing. In this region pain is first processed and the sensory aspects of pain perception is elaborated and then conveyed to the anterior insula where it is related to emotional and cognitive aspects of pain perception. The data corroborate that GABA levels seem to be an important mediator for pain perception. 5646. 86 Altered intrinsic neuronal activity correlates with GABA levels in the auditory region of patients with presbycusis Fei Gao, Guangbin Wang, Bin Zhao, Fuxin Ren, Weibo Chen In this study, we used J-difference edited MRS and resting-state fMRI to investigate correlation between intrinsic neuronal activity and GABA levels in the auditory cortex of patients with presbycusis. Our results indicated that abnormalities in GABAergic neurotransmission may underlie resting-state functional deficits in presbycusis. 5647. 87 Investigation of metabolic changes during watching movie using fMRS at 3T system Jia-Ren Lin, Yi-Ru Lin, Shang-Yueh Tsai Recent studies have reported metabolic change during visual and motor stimulation using MRS at 7T MRI system. We think there is potential to perform fMRS experiments at 3T system. Visual stimuli were given with block design consisting of 2 black-white movie clips and 3 rest sections. Our preliminary results showed that Glu concentrations in visual cortex increases by 1.39% during watching movie, while NAA and Cre have no significant change. The observed Glu change was comparable to previous study performed at 7T. 5648. 88 Identification of Prostate Cancer with MR Spectroscopic Imaging and Diffusion-weighted Imaging at 3 Tesla Yousef Mazaheri, Amita Shukla-Dave, Debra Goldman, Chaya Moskowitz, Victor Reuter, Oguz Akin, Hedvig Hricak The aims of our study were to retrospectively measure metabolite ratios and apparent diffusion coefficient values for benign and malignant PZ tissue at 3T, develop statistically-based rules for classifying benign and malignant PZ tissue, and assess the rules’ performance, using whole-mount step-section pathology as the reference standard. 5649. 89 Using broadband refocusing pulses for increased sensitivity for 2HG detection to determine glioma IDH mutation status Sunitha Thakur, Robert Young, Robin Fatovic, Ralph Noeske, Martin Janich, Andrei Holodny, Ingo Mellinghoff 2-hydroxyglutarate in IDH1/2 mutated tumors is of clinical interest and can be measured in-vivo by magnetic resonance spectroscopy. Goal of this work was to compare results obtained using the standard reduced flip angle refocusing pulses with results using broadband refocusing pulses. Sensitivity improvement was observed in phantoms and demonstrated in vivo. 5650. 90 1H NMR based metabolomics study of serum in Parkinson’s patients Sadhana Kumari, Senthil Kumaran, Vinay Goyal, SN Dwivedi, Achal Srivastava, Naranamangalam Jagannathan Proton metabolic profile of serum samples in 20 patients with Parkinson’s disease (PD) and 10 healthy controls (HC) was studied using 700 MHz NMR spectrometer. Data were processed using MestReNova software (version: 10.0) and integral values were evaluated. PLS-DA multivariate analysis was performed to compare the metabolic differences between PD patients and HC using MetaboAnalyst (version: 3.0) software. We found elevated levels of glucose, fatty acid, glutamine, lactate, choline, creatine and acetate in PD patients in comparison with HC (on t-test, p<0.05), indicating disturbances in lipid metabolism, fatty acid oxidation and mitochondrial damage leading to dopaminergic deficiency in Parkinson's disease. 5651. 91 NEURO 2D CORRELATED  SPECTROSCOPY  IDENTIFIES  NEURO DEREGULATION IN SOLDIERS EXPOSED TO BLAST  PRIOR TO  DISCERNIBLE CHANGES BY CONVENTIONAL IMAGING Graham Galloway, Scott Quadrelli, Aaron Urquhart, Katie Trickey, Peter Malycha, Theresa Keane, Carolyn Mountford This pilot study reports clear deregulation in the neurochemistry  of defense personnel exposed to repeated blast. The changes  recorded are different to those reported for mTBI, PTSD and chronic pain. No differences between blast exposed and healthy were recorded by MRI sequences T1WI, FLAIR or SWI. In vivo neuro 2D spectroscopy  recorded deregulation with PC and GPC, NAA and GABA all decreased compared to the healthy non exposed brain. We we did not observe any changes in the fucosolated glycans, which are reflective of pain, repetitive brain injury  and/or cognitive deficit. 5655. 95 Investigation of long-term effect of a high-fat diet using quantitative MRI and 1H MRS for assessing body and liver fat, and muscle mass - permission withheld Jong-Hee Hwang, In-Young Lee, Jung-Hyun Kim, Jae Seung Kim Repetitive and noninvasive MR examinations of fat content can provide indispensable information for longitudinal metabolic studies. It is of great interest to understand how obesity in youth affects the fat metabolism later in life. Thus we longitudinally examined mice with/without a high-fat diet [HFD] for 8 weeks from 13 to 67 weeks old using MRI and 1H MRS.  As a result, visceral fat restored normalcy in 10 weeks after the termination of HFD, subcutaneous and liver fat returned to normalcy in ~ 16 - 20 weeks as compared to controls. 5652. 92 7T Brain MRS in HIV Infection: Effects of Cognitive Impairment Mona Mohamed, Peter Barker, Richard Skolasky, Ned Sacktor Higher magnetic field such as 7T provides increased sensitivity, better signal to noise ratio and more reliable measure of the metabolite concentrations. In this study, 7T MRS was used to measure brain metabolites in HIV+ patients in 5 brain regions. Our study showed impaired neuronal integrity across the white and gray matter as well as possible impaired astrocyte osmoregulation in patients with symptomatic cognitive impairment. In conclusion, 7T MRS brain metabolites measurement can be used as reliable biomarkers for the assessment of cognitive status in HIV+ patients. 5653. 93 Microstructural dynamic changes in ischemic stroke in humans measured with diffusion-weighted magnetic resonance spectroscopy at 3 T Francesca Branzoli, Bélen Díaz-Fernández , Malgorzata Marjanska, Edward Auerbach, Romain Valabrègue, Itamar Ronen, Stéphane Lehéricy, Charlotte Rosso Diffusion-weighted 1H magnetic resonance spectroscopy (DW-MRS) probes the diffusion properties of metabolites, which are differentially compartmentalized in brain tissue and are thus more specific than water molecules to the intra-cellular environment. The aim of this study was to measure water and metabolite diffusion in the human brain in the acute, sub-acute and choronic stage of ischemic stroke, in order to better characterize the microstructural dynamic changes ongoing at different stages of the disease, in both infarcted and periferal regions, by disentangling neuronal, glial and extra-cellular pathological processes. 5654. 94 Enhanced detection of weak metabolites with short initial echo time 2D L-COSY Jameen ARM, Karen Ribbons, Jeannette Lechner-Scott, Kate Skehan, Shiami Luchow, M. Albert Thomas, Saadallah Ramadan The detection of weak neurometabolites such as g-aminobutyric acid (GABA), glutathione (GSH), glycerophosphocholine (GPC), phosphorylethanolamine (PE) with 2D L-COSY can be challenging due to lower concentrations. Moreover, the standard initial echo time (TEinitial) of 30ms yields suboptimal SNR due to shorter T2*. In this study, we compared short TEinitial of 20ms vs 30ms to evaluate improved detection of low concentration metabolites. Our results show a significant increase in SNR with TEinitial of 20ms compared to 30ms. Short TEinitial of 20ms has increased potential in the detection of peaks from weak neurometabolites.
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