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https://www.readbyqxmd.com/read/29325780/longitudinal-atlas-for-normative-human-brain-development-and-aging-over-the-lifespan-using-quantitative-susceptibility-mapping
#1
Yuyao Zhang, Hongjiang Wei, Matthew J Cronin, Naying He, Fuhua Yan, Chunlei Liu
Longitudinal brain atlases play an important role in the study of human brain development and cognition. Existing atlases are mainly based on anatomical features derived from T1-and T2-weighted MRI. A 4D developmental quantitative susceptibility mapping (QSM) atlas may facilitate the estimation of age-related iron changes in deep gray matter nuclei and myelin changes in white matter. To this end, group-wise co-registered QSM templates were generated over various age intervals from age 1-83 years old. Registration was achieved by combining both T1-weighted and QSM images...
January 8, 2018: NeuroImage
https://www.readbyqxmd.com/read/29314215/simultaneous-quantitative-susceptibility-mapping-qsm-and-r2-for-high-iron-concentration-quantification-with-3d-ultrashort-echo-time-sequences-an-echo-dependence-study
#2
Xing Lu, Yajun Ma, Eric Y Chang, Qun He, Adam Searleman, Annette von Drygalski, Jiang Du
PURPOSE: To evaluate the echo dependence of 3D ultrashort echo time (TE) quantitative susceptibility mapping (3D UTE-QSM) and effective transverse relaxation rate ( R2*) measurement in the setting of high concentrations of iron oxide nanoparticles. METHODS: A phantom study with iron concentrations ranging from 2 to 22 mM was performed using a 3D UTE Cones sequence. Simultaneous QSM processing with morphology-enabled dipole inversion (MEDI) and R2* single exponential fitting was conducted offline with the acquired 3D UTE data...
January 4, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29297155/brain-iron-deposition-in-type-2-diabetes-mellitus-with-and-without-mild-cognitive-impairment-an-in-vivo-susceptibility-mapping-study
#3
Qifang Yang, Lina Zhou, Chen Liu, Daihong Liu, Yang Zhang, Chang Li, Yongning Shang, Xin Wei, Chuanming Li, Jian Wang
This study was performed to investigate iron deposition in the brain of type 2 diabetes mellitus (T2DM) patients using quantitative susceptibility mapping (QSM) and the associated cognitive impairments. Sixty patients diagnosed with T2DM were subjected to neuropsychological tests to determine their cognitive status, and the results were used to subdivide the patients into a T2DM without mild cognitive impairment (MCI) group (n = 30) and a T2DM with MCI group (n = 30). All patients underwent high-resolution susceptibility-weighted imaging, and data processing was performed using SMART (Susceptibility Mapping and Phase Artifacts Removal Toolbox) software...
January 3, 2018: Brain Imaging and Behavior
https://www.readbyqxmd.com/read/29261693/ex-vivo-quantitative-susceptibility-mapping-of-human-brain-hemispheres
#4
Arnold M Evia, Aikaterini Kotrotsou, Ashish A Tamhane, Robert J Dawe, Alifiya Kapasi, Sue E Leurgans, Julie A Schneider, David A Bennett, Konstantinos Arfanakis
Ex-vivo brain quantitative susceptibility mapping (QSM) allows investigation of brain characteristics at essentially the same point in time as histopathologic examination, and therefore has the potential to become an important tool for determining the role of QSM as a diagnostic and monitoring tool of age-related neuropathologies. In order to be able to translate the ex-vivo QSM findings to in-vivo, it is crucial to understand the effects of death and chemical fixation on brain magnetic susceptibility measurements collected ex-vivo...
2017: PloS One
https://www.readbyqxmd.com/read/29249064/reduced-deep-regional-cerebral-venous-oxygen-saturation-in-hemodialysis-patients-using-quantitative-susceptibility-mapping
#5
Chao Chai, Saifeng Liu, Linlin Fan, Lei Liu, Jinping Li, Chao Zuo, Tianyi Qian, E Mark Haacke, Wen Shen, Shuang Xia
Cerebral venous oxygen saturation (SvO2) is an important indicator of brain function. There was debate about lower cerebral oxygen metabolism in hemodialysis patients and there were no reports about the changes of deep regional cerebral SvO2 in hemodialysis patients. In this study, we aim to explore the deep regional cerebral SvO2 from straight sinus using quantitative susceptibility mapping (QSM) and the correlation with clinical risk factors and neuropsychiatric testing. 52 hemodialysis patients and 54 age-and gender-matched healthy controls were enrolled...
December 16, 2017: Metabolic Brain Disease
https://www.readbyqxmd.com/read/29201641/iron-related-gene-variants-and-brain-iron-in-multiple-sclerosis-and-healthy-individuals
#6
Jesper Hagemeier, Murali Ramanathan, Ferdinand Schweser, Michael G Dwyer, Fuchun Lin, Niels Bergsland, Bianca Weinstock-Guttman, Robert Zivadinov
Brain iron homeostasis is known to be disturbed in multiple sclerosis (MS), yet little is known about the association of common gene variants linked to iron regulation and pathological tissue changes in the brain. In this study, we investigated the association of genetic determinants linked to iron regulation with deep gray matter (GM) magnetic susceptibility in both healthy controls (HC) and MS patients. Four hundred (400) patients with MS and 150 age- and sex-matched HCs were enrolled and obtained 3 T MRI examination...
2018: NeuroImage: Clinical
https://www.readbyqxmd.com/read/29177950/vascular-and-tissue-changes-of-magnetic-susceptibility-in-the-mouse-brain-after-transient-cerebral-ischemia
#7
Markus Vaas, Andreas Deistung, Jürgen R Reichenbach, Annika Keller, Anja Kipar, Jan Klohs
Quantitative susceptibility mapping (QSM) has been recently introduced as a novel MRI post-processing technique of gradient recalled echo (GRE) data. QSM is useful in depicting both brain anatomy and for detecting abnormalities. Its utility in the context of ischemic stroke has, however, not been extensively characterized so far. In this study, we explored the potential of QSM to characterize vascular and tissue changes in the transient middle cerebral artery occlusion (tMCAO) mouse model of cerebral ischemia...
November 25, 2017: Translational Stroke Research
https://www.readbyqxmd.com/read/29162523/specific-visualization-of-neuromelanin-iron-complex-and-ferric-iron-in-the-human-post-mortem-substantia-nigra-using-mr-relaxometry-at-7t
#8
Hansol Lee, Sun-Yong Baek, Se Young Chun, Jae-Hyeok Lee, HyungJoon Cho
Neuromelanin (NM) is an endogenous iron chelating molecule of pigmented neurons in the human substantia nigra (SN). Along with the increase in iron deposition, the reduction in NM-containing dopaminergic neurons and the variation of iron load on NM are generally considered to be important factors participating to pathogenesis of Parkinson's disease (PD). The aim of this study was to non-invasively delineate the spatial distributions of paramagnetic magnetic susceptibility perturbers, such as NM-iron complex and ferric iron in SN...
November 21, 2017: NeuroImage
https://www.readbyqxmd.com/read/29154893/an-interleaved-sequence-for-simultaneous-magnetic-resonance-angiography-mra-susceptibility-weighted-imaging-swi-and-quantitative-susceptibility-mapping-qsm
#9
Yongsheng Chen, Saifeng Liu, Sagar Buch, Jiani Hu, Yan Kang, E Mark Haacke
PURPOSE: To image the entire vasculature of the brain with complete suppression of signal from background tissue using a single 3D excitation interleaved rephased/dephased multi-echo gradient echo sequence. This ensures no loss of signal from fast flow and provides co-registered susceptibility weighted images (SWI) and quantitative susceptibility maps (QSM) from the same scan. MATERIALS AND METHODS: The suppression of background tissue was accomplished by subtracting the flow-dephased images from the flow-rephased images with the same echo time of 12...
November 14, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29138089/rapid-two-step-dipole-inversion-for-susceptibility-mapping-with-sparsity-priors
#10
Christian Kames, Vanessa Wiggermann, Alexander Rauscher
Quantitative susceptibility mapping (QSM) is a post-processing technique of gradient echo phase data that attempts to map the spatial distribution of local tissue magnetic susceptibilities. To obtain these maps, an ill-posed field-to-source inverse problem must be solved to remove non-local magnetic field perturbations. Current state-of-the-art algorithms which aim to solve the dipole inversion problem are plagued by the trade-off between reconstruction speed and accuracy. A two-step dipole inversion algorithm is proposed to bridge this gap...
November 11, 2017: NeuroImage
https://www.readbyqxmd.com/read/29130526/phase-processing-for-quantitative-susceptibility-mapping-of-regions-with-large-susceptibility-and-lack-of-signal
#11
Véronique Fortier, Ives R Levesque
PURPOSE: Phase processing impacts the accuracy of quantitative susceptibility mapping (QSM). Techniques for phase unwrapping and background removal have been proposed and demonstrated mostly in brain. In this work, phase processing was evaluated in the context of large susceptibility variations (Δχ) and negligible signal, in particular for susceptibility estimation using the iterative phase replacement (IPR) algorithm. METHODS: Continuous Laplacian, region-growing, and quality-guided unwrapping were evaluated...
November 11, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29079523/combining-images-and-anatomical-knowledge-to-improve-automated-vein-segmentation-in-mri
#12
Phillip G D Ward, Nicholas J Ferris, Parnesh Raniga, David L Dowe, Amanda C L Ng, David G Barnes, Gary F Egan
PURPOSE: To improve the accuracy of automated vein segmentation by combining susceptibility-weighted images (SWI), quantitative susceptibility maps (QSM), and a vein atlas to produce a resultant image called a composite vein image (CV image). METHOD: An atlas was constructed in common space from manually traced MRI images from ten volunteers. The composite vein image was derived for each subject as a weighted sum of three inputs; an SWI image, a QSM image and the vein atlas...
October 25, 2017: NeuroImage
https://www.readbyqxmd.com/read/29075619/modulating-the-global-response-regulator-luxo-of-v-cholerae-quorum-sensing-system-using-a-pyrazine-dicarboxylic-acid-derivative-pdca-py-an-antivirulence-approach
#13
M Hema, Sahana Vasudevan, P Balamurugan, S Adline Princy
Vibrio cholerae is a Gram-negative pathogen which causes acute diarrhoeal disease, cholera by the expression of virulence genes through quorum sensing (QS) mechanism. The QS circuit of V. cholerae is controlled by the global quorum regulator, LuxO, which at low cell density (LCD) state produces major virulence factors such as, toxin co-regulated pilus (TCP) and cholera toxin (CT) to mediate infection. On the contrary, at the high cell density (HCD) state the virulent genes are downregulated and the vibrios are detached from the host intestinal epithelial cells, promoted by HapA protease...
2017: Frontiers in Cellular and Infection Microbiology
https://www.readbyqxmd.com/read/29067730/simultaneous-qsm-and-metabolic-imaging-of-the-brain-using-spice
#14
Xi Peng, Fan Lam, Yudu Li, Bryan Clifford, Zhi-Pei Liang
PURPOSE: To map brain metabolites and tissue magnetic susceptibility simultaneously using a single three-dimensional (1) H-MRSI acquisition without water suppression. METHODS: The proposed technique builds on a subspace imaging method called spectroscopic imaging by exploiting spatiospectral correlation (SPICE), which enables ultrashort echo time (TE)/short pulse repetition time (TR) acquisitions for (1) H-MRSI without water suppression. This data acquisition scheme simultaneously captures both the spectral information of brain metabolites and the phase information of the water signals that is directly related to tissue magnetic susceptibility variations...
October 24, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29056394/strategically-acquired-gradient-echo-stage-imaging-part-i-creating-enhanced-t1-contrast-and-standardized-susceptibility-weighted-imaging-and-quantitative-susceptibility-mapping
#15
Yongsheng Chen, Saifeng Liu, Yu Wang, Yan Kang, E Mark Haacke
PURPOSE: To provide whole brain grey matter (GM) to white matter (WM) contrast enhanced T1W (T1WE) images, multi-echo quantitative susceptibility mapping (QSM), proton density (PD) weighted images, T1 maps, PD maps, susceptibility weighted imaging (SWI), and R2* maps with minimal misregistration in scanning times <5min. METHODS: Strategically acquired gradient echo (STAGE) imaging includes two fully flow compensated double echo gradient echo acquisitions with a resolution of 0...
October 19, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29023982/medi-0-morphology-enabled-dipole-inversion-with-automatic-uniform-cerebrospinal-fluid-zero-reference-for-quantitative-susceptibility-mapping
#16
Zhe Liu, Pascal Spincemaille, Yihao Yao, Yan Zhang, Yi Wang
PURPOSE: To develop a quantitative susceptibility mapping (QSM) method with a consistent zero reference using minimal variation in cerebrospinal fluid (CSF) susceptibility. THEORY AND METHODS: The ventricular CSF was automatically segmented on the R2* map. An L2 -regularization was used to enforce CSF susceptibility homogeneity within the segmented region, with the averaged CSF susceptibility as the zero reference. This regularization for CSF homogeneity was added to the model used in a prior QSM method (morphology enabled dipole inversion [MEDI])...
October 11, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29018934/quantitative-susceptibility-mapping-of-the-motor-cortex-a-comparison-of-susceptibility-among-patients-with-amyotrophic-lateral-sclerosis-cerebrovascular-disease-and-healthy-controls
#17
Ji Young Lee, Young-Jun Lee, Dong Woo Park, Yoonho Nam, Seung Hyun Kim, Jinseok Park, Young Seo Kim, Hyun Young Kim, Ki-Wook Oh
PURPOSE: The purpose of this study was to investigate the differences in motor cortex susceptibility among patients with amyotrophic lateral sclerosis (ALS), cerebrovascular disease (CVD), and healthy controls using quantitative susceptibility mapping (QSM). METHODS: We retrospectively reviewed 78 QSM images from 26 patients with ALS, 26 age- and sex-matched patients with CVD, and 26 healthy controls. A region of interest was drawn in the hand lobule of both the motor cortexes and subcortical white matter...
December 2017: Neuroradiology
https://www.readbyqxmd.com/read/28902421/the-impact-of-white-matter-fiber-orientation-in-single-acquisition-quantitative-susceptibility-mapping
#18
Marta Lancione, Michela Tosetti, Graziella Donatelli, Mirco Cosottini, Mauro Costagli
The aim of this work was to assess the impact of tissue structural orientation on quantitative susceptibility mapping (QSM) reliability, and to provide a criterion to identify voxels in which measures of magnetic susceptibility (χ) are most affected by spatial orientation effects. Four healthy volunteers underwent 7-T magnetic resonance imaging (MRI). Multi-echo, gradient-echo sequences were used to obtain quantitative maps of frequency shift (FS) and χ. Information from diffusion tensor imaging (DTI) was used to investigate the relationship between tissue orientation and FS measures and QSM...
September 13, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/28900391/quantitative-susceptibility-mapping-reveals-an-association-between-brain-iron-load-and-depression-severity
#19
Shun Yao, Yi Zhong, Yuhao Xu, Jiasheng Qin, Ningning Zhang, Xiaolan Zhu, Yuefeng Li
Previous studies have detected abnormal serum ferritin levels in patients with depression; however, the results have been inconsistent. This study used quantitative susceptibility mapping (QSM) for the first time to examine brain iron concentration in depressed patients and evaluated whether it is related to severity. We included three groups of age- and gender-matched participants: 30 patients with mild-moderate depression (MD), 14 patients with major depression disorder (MDD) and 20 control subjects. All participants underwent MR scans with a 3D gradient-echo sequence reconstructing for QSM and performed the 17-item Hamilton Depression Rating Scale (HDRS) test...
2017: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/28886909/quantitative-susceptibility-mapping-differentiates-between-parkinsonian-disorders
#20
Henrik Sjöström, Tobias Granberg, Eric Westman, Per Svenningsson
INTRODUCTION: It is often challenging to clinically distinguish between Parkinson's disease (PD), multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Quantitative susceptibility mapping (QSM) is an accurate indirect method for estimating brain iron levels in vivo. This method has yet to be applied in atypical parkinsonism. We aimed to investigate differences in brain iron accumulation parkinsonian disorders and healthy controls using QSM. METHODS: 15 patients with PSP, 11 patients with MSA, 62 patients with PD and 14 healthy controls were included in the study and their phase and magnitude data from susceptibility-weighted magnetic resonance imaging were retrospectively analyzed with an in-house pipeline to create susceptibility maps...
September 1, 2017: Parkinsonism & related Disorders
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