keyword
MENU ▼
Read by QxMD icon Read
search

Qsm

keyword
https://www.readbyqxmd.com/read/28902421/the-impact-of-white-matter-fiber-orientation-in-single-acquisition-quantitative-susceptibility-mapping
#1
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
#2
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
#3
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
https://www.readbyqxmd.com/read/28885147/quantitative-susceptibility-mapping-qsm-algorithms-mathematical-rationale-and-computational-implementations
#4
Youngwook Kee, Zhe Liu, Liangdong Zhou, Alexey Dimov, Junghun Cho, Ludovic de Rochefort, Jin Keun Seo, Yi Wang
Quantitative susceptibility mapping (QSM) solves the magnetic field-to-magnetization (tissue susceptibility) inverse problem under conditions of noisy and incomplete field data acquired using magnetic resonance imaging. Sophisticated algorithms are, therefore, necessary to treat the ill-posed nature of the problem and are reviewed here. The forward problem is typically presented as an integral form, where the field is the convolution of the dipole kernel and tissue susceptibility distribution. This integral form can be equivalently written as a partial differential equation (PDE)...
September 5, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28879084/quantitative-susceptibility-mapping-to-evaluate-the-early-stage-of-alzheimer-s-disease
#5
Hyug-Gi Kim, Soonchan Park, Hak Young Rhee, Kyung Mi Lee, Chang-Woo Ryu, Sun Jung Rhee, Soo Yeol Lee, Yi Wang, Geon-Ho Jahng
The objective of this study was to evaluate susceptibility changes caused by iron accumulation in cognitive normal (CN) elderly, those with amnestic mild cognitive impairment (aMCI), and those with early state AD, and to compare the findings with gray matter volume (GMV) changes caused by neuronal loss. The participants included 19 elderly CN, 19 aMCI, and 19 AD subjects. The voxel-based quantitative susceptibility map (QSM) and GMV in the brain were calculated and the differences of those insides were compared among the three groups...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28815906/deep-gray-matter-iron-measurement-in-patients-with-liver-cirrhosis-using-quantitative-susceptibility-mapping-relationship-with-pallidal-t1-hyperintensity
#6
Song Lee, Yoonho Nam, Jinhee Jang, Gun Hyung Na, Dong Goo Kim, Na-Young Shin, Hyun Seok Choi, So-Lyung Jung, Kook-Jin Ahn, Bum-Soo Kim
BACKGROUND: The liver is a central organ for the metabolism of iron and manganese and the places where those metals are commonly deposited overlap in the brain. PURPOSE/HYPOTHESIS: To elucidate the relationship between pallidal T1 hyperintensity and iron deposition in the deep gray matter of liver cirrhosis patients using quantitative susceptibility mapping (QSM). STUDY TYPE: Retrospective case-control study SUBJECTS: In all, 38 consecutive liver cirrhosis patients who received brain magnetic resonance imaging (MRI) as pretransplant evaluation...
August 17, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28797738/tissue-magnetic-susceptibility-mapping-as-a-marker-of-tau-pathology-in-alzheimer-s-disease
#7
J O'Callaghan, H Holmes, N Powell, J A Wells, O Ismail, I F Harrison, B Siow, R Johnson, Z Ahmed, A Fisher, S Meftah, M J O'Neill, T K Murray, E C Collins, K Shmueli, M F Lythgoe
Alzheimer's disease is connected to a number of other neurodegenerative conditions, known collectively as 'tauopathies', by the presence of aggregated tau protein in the brain. Neuroinflammation and oxidative stress in AD are associated with tau pathology and both the breakdown of axonal sheaths in white matter tracts and excess iron accumulation grey matter brain regions. Despite the identification of myelin and iron concentration as major sources of contrast in quantitative susceptibility maps of the brain, the sensitivity of this technique to tau pathology has yet to be explored...
August 4, 2017: NeuroImage
https://www.readbyqxmd.com/read/28791783/quantitative-susceptibility-mapping-as-a-monitoring-biomarker-in-cerebral-cavernous-malformations-with-recent-hemorrhage
#8
Hussein A Zeineddine, Romuald Girard, Ying Cao, Nicholas Hobson, Maged D Fam, Agnieszka Stadnik, Huan Tan, Jingjing Shen, Kiranj Chaudagar, Robert Shenkar, Richard E Thompson, Nichol McBee, Daniel Hanley, Timothy Carroll, Gregory A Christoforidis, Issam A Awad
BACKGROUND: Quantitative Susceptibility Mapping (QSM) MRI allows accurate assessment of iron content in cerebral cavernous malformations (CCM), and a threshold increase by 6% in QSM has been shown to reflect new symptomatic hemorrhage (SH) in previously stable lesions. PURPOSE/HYPOTHESIS: It is unclear how lesional QSM evolves in CCMs after recent SH, and whether this could serve as a monitoring biomarker in clinical trials aimed at preventing rebleeding in these lesions...
August 9, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28762243/quantitative-susceptibility-mapping-report-from-the-2016-reconstruction-challenge
#9
Christian Langkammer, Ferdinand Schweser, Karin Shmueli, Christian Kames, Xu Li, Li Guo, Carlos Milovic, Jinsuh Kim, Hongjiang Wei, Kristian Bredies, Sagar Buch, Yihao Guo, Zhe Liu, Jakob Meineke, Alexander Rauscher, José P Marques, Berkin Bilgic
PURPOSE: The aim of the 2016 quantitative susceptibility mapping (QSM) reconstruction challenge was to test the ability of various QSM algorithms to recover the underlying susceptibility from phase data faithfully. METHODS: Gradient-echo images of a healthy volunteer acquired at 3T in a single orientation with 1.06 mm isotropic resolution. A reference susceptibility map was provided, which was computed using the susceptibility tensor imaging algorithm on data acquired at 12 head orientations...
July 31, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28747100/loading-and-elution-characteristics-of-quadrasphere-microspheres-loaded-with-bevacizumab
#10
Martin Oselkin, Neda I Sedora-Roman, Bryan A Pukenas, David Kung, Robert W Hurst
AIM: Super absorbent polyvinyl alcohol-sodium acrylate copolymer microspheres, Quadrasphere microspheres (QSM), are commonly used for drug-eluting bead therapy, however, the literature only reports its use with small molecule chemotherapeutics. This study evaluates the loading and elution characteristics of bevacizumab-loaded QSM. METHODS & RESULTS: A single vial of QSM was reconstituted with 200 mg of bevacizumab. Drug concentration was determined by ELISA immunoassay...
July 27, 2017: Therapeutic Delivery
https://www.readbyqxmd.com/read/28731570/susceptibility-weighted-imaging-and-quantitative-susceptibility-mapping-of-the-cerebral-vasculature-using-ferumoxytol
#11
Saifeng Liu, Jean-Christophe Brisset, Jiani Hu, E Mark Haacke, Yulin Ge
PURPOSE: To demonstrate the potential of imaging cerebral arteries and veins with ferumoxytol using susceptibility weighted imaging (SWI) and quantitative susceptibility mapping (QSM). MATERIALS AND METHODS: The relationships between ferumoxytol concentration and the apparent susceptibility at 1.5T, 3T, and 7T were determined using phantom data; the ability of visualizing subvoxel vessels was evaluated using simulations; and the feasibility of using ferumoxytol to enhance the visibility of small vessels was confirmed in three healthy volunteers at 7T(with doses 1 mg/kg to 4 mg/kg)...
July 21, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28689259/differential-diagnosis-of-parkinsonism-by-a-combined-use-of-diffusion-kurtosis-imaging-and-quantitative-susceptibility-mapping
#12
Kenji Ito, Chigumi Ohtsuka, Kunihiro Yoshioka, Hiroyuki Kameda, Suguru Yokosawa, Ryota Sato, Yasuo Terayama, Makoto Sasaki
PURPOSE: We investigated whether diffusion kurtosis imaging (DKI) and quantitative susceptibility mapping (QSM) could detect pathological changes that occur in Parkinson's disease (PD), multiple system atrophy with predominant parkinsonism (MSA-P) or predominant cerebellar ataxia (MSA-C), and progressive supranuclear palsy syndrome (PSPS) and thus be used for differential diagnosis that is often difficult. METHODS: Seventy patients (41 with PD, 6 with MSA-P, 7 with MSA-C, 16 with PSPS) and 20 healthy controls were examined using a 3...
August 2017: Neuroradiology
https://www.readbyqxmd.com/read/28674518/brain-susceptibility-changes-in-a-patient-with-natalizumab-related-progressive-multifocal-leukoencephalopathy-a-longitudinal-quantitative-susceptibility-mapping-and-relaxometry-study
#13
Giuseppe Pontillo, Sirio Cocozza, Roberta Lanzillo, Pasquale Borrelli, Anna De Rosa, Vincenzo Brescia Morra, Enrico Tedeschi, Giuseppe Palma
BACKGROUND: Brain MRI plays an essential role in both diagnosis and follow-up of the JC virus infection of the brain. Recently, MR studies with susceptibility-weighted imaging (SWI) sequences have shown hypointensities in U-fibers adjacent to white matter (WM) lesions of progressive multifocal leukoencephalopathy (PML). This finding has been confirmed with the use of quantitative susceptibility mapping (QSM), allowing to hypothesize a paramagnetic effect in these regions. Here, we report the first longitudinal assessment of QSM and R2* maps in natalizumab-associated PML to evaluate serial changes in susceptibility contrast images and their role in PML diagnosis and follow-up...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/28669058/improved-neuroimaging-atlas-of-the-dentate-nucleus
#14
Naying He, Jason Langley, Daniel E Huddleston, Huawei Ling, Hongmin Xu, Chunlei Liu, Fuhua Yan, Xiaoping P Hu
The dentate nucleus (DN) of the cerebellum is the major output nucleus of the cerebellum and is rich in iron. Quantitative susceptibility mapping (QSM) provides better iron-sensitive MRI contrast to delineate the boundary of the DN than either T2-weighted images or susceptibility-weighted images. Prior DN atlases used T2-weighted or susceptibility-weighted images to create DN atlases. Here, we employ QSM images to develop an improved dentate nucleus atlas for use in imaging studies. The DN was segmented in QSM images from 38 healthy volunteers...
July 1, 2017: Cerebellum
https://www.readbyqxmd.com/read/28664033/decreased-susceptibility-of-major-veins-in-mild-traumatic-brain-injury-is-correlated-with-post-concussive-symptoms-a-quantitative-susceptibility-mapping-study
#15
Chao Chai, Rui Guo, Chao Zuo, Linlin Fan, Saifeng Liu, Tianyi Qian, E Mark Haacke, Shuang Xia, Wen Shen
Cerebral venous oxygen saturation (SvO2) is an important biomarker of brain function. In this study, we aimed to explore the relative changes of regional cerebral SvO2 among axonal injury (AI) patients, non-AI patients and healthy controls (HCs) using quantitative susceptibility mapping (QSM). 48 patients and 32 HCs were enrolled. The patients were divided into two groups depending on the imaging based evidence of AI. QSM was used to measure the susceptibility of major cerebral veins. Nonparametric testing was performed for susceptibility differences among the non-AI patient group, AI patient group and healthy control group...
2017: NeuroImage: Clinical
https://www.readbyqxmd.com/read/28663515/noninvasive-assessment-of-oxygen-extraction-fraction-in-chronic-ischemia-using-quantitative-susceptibility-mapping-at-7-tesla
#16
Ikuko Uwano, Kohsuke Kudo, Ryota Sato, Kuniaki Ogasawara, Hiroyuki Kameda, Jun-Ichi Nomura, Futoshi Mori, Fumio Yamashita, Kenji Ito, Kunihiro Yoshioka, Makoto Sasaki
BACKGROUND AND PURPOSE: The oxygen extraction fraction (OEF) is an effective metric to evaluate metabolic reserve in chronic ischemia. However, OEF is considered to be accurately measured only when using positron emission tomography (PET). Thus, we investigated whether OEF maps generated by magnetic resonance quantitative susceptibility mapping (QSM) at 7 Tesla enabled detection of OEF changes when compared with those obtained with PET. METHODS: Forty-one patients with chronic stenosis/occlusion of the unilateral internal carotid artery or middle cerebral artery were examined using 7 Tesla-MRI and PET scanners...
August 2017: Stroke; a Journal of Cerebral Circulation
https://www.readbyqxmd.com/read/28653375/cardiac-quantitative-susceptibility-mapping-qsm-for-heart-chamber-oxygenation
#17
Yan Wen, Thanh D Nguyen, Zhe Liu, Pascal Spincemaille, Dong Zhou, Alexey Dimov, Youngwook Kee, Kofi Deh, Jiwon Kim, Jonathan W Weinsaft, Yi Wang
PURPOSE: To demonstrate the feasibility of in vivo quantitative susceptibility mapping (QSM) in cardiac MRI and to show that mixed-venous oxygen saturation (SvO2 ) can be measured non-invasively using QSM. METHODS: Electrocardiographic-gated multi-echo 2D gradient echo data were collected at 1.5 T from 14 healthy volunteers during successive breath-holds. Phase wraps and fat chemical shift were removed using a graph-cut-based phase analysis and IDEAL in an iterative approach...
June 26, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28631203/assessment-of-mri-contrast-agent-concentration-by-quantitative-susceptibility-mapping-qsm-application-to-estimation-of-cerebral-blood-volume-during-steady-state
#18
Emelie Lind, Linda Knutsson, Robin Kämpe, Freddy Ståhlberg, Ronnie Wirestam
OBJECTIVE: One major issue in dynamic susceptibility contrast MRI (DSC-MRI) is to accurately determine contrast agent (CA) concentration, since T2* relaxivity in vivo is generally unknown and varies between blood and tissue. In this study, quantitative susceptibility mapping (QSM) was used for quantification of CA concentration. MATERIALS AND METHODS: A DSC-MRI protocol, including phase data acquisition, was applied to 20 healthy volunteers in a test-retest study...
June 19, 2017: Magma
https://www.readbyqxmd.com/read/28602813/automated-segmentation-of-midbrain-structures-with-high-iron-content
#19
REVIEW
Benjamín Garzón, Rouslan Sitnikov, Lars Bäckman, Grégoria Kalpouzos
The substantia nigra (SN), the subthalamic nucleus (STN), and the red nucleus (RN) are midbrain structures of ample interest in many neuroimaging studies, which may benefit from the availability of automated segmentation methods. The high iron content of these structures awards them high contrast in quantitative susceptibility mapping (QSM) images. We present a novel segmentation method that leverages the information of these images to produce automated segmentations of the SN, STN, and RN. The algorithm builds a map of spatial priors for the structures by non-linearly registering a set of manually-traced training labels to the midbrain...
June 9, 2017: NeuroImage
https://www.readbyqxmd.com/read/28601374/quantitative-susceptibility-mapping-qsm-and-r2-in-the-human-brain-at-3t-evaluation-of-intra-scanner-repeatability
#20
Xiang Feng, Andreas Deistung, Jürgen R Reichenbach
Quantitative susceptibility mapping (QSM) and the effective transverse relaxation rate (R2*) can be used to monitor iron and myelin content in brain tissue, which are both subject to changes in many neurological diseases but also during healthy aging. In this study, we quantitatively assessed the repeatability of QSM and R2* by applying four independent scans in eight young healthy, female subjects on a 3T MRI scanner. Since QSM does not yield absolute values for bulk magnetic susceptibilities, we additionally investigated the influence of the choice of a reference brain region for susceptibility by computing susceptibility differences with respect to five different brain structures (whole brain, frontal white matter (fWM), internal capsule (IC), cerebrospinal fluid (CSF) in the lateral ventricle, cortical gray matter (cGM))...
June 7, 2017: Zeitschrift Für Medizinische Physik
keyword
keyword
40463
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"