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https://www.readbyqxmd.com/read/28219360/interobserver-and-intraobserver-agreement-of-ligamentous-injuries-on-conventional-mri-after-simple-elbow-dislocation
#1
Marc Schnetzke, Svenja Schüler, Johannes Hoffend, Rainer Simon, Holger Keil, Felix Porschke, Stefan Studier-Fischer, Paul-Alfred Grützner, Thorsten Guehring
BACKGROUND: The primary objective of this study was to assess the interobserver and intraobserver agreement on ligamentous injuries on conventional magnetic resonance imaging (MRI) in acute simple elbow dislocation. The secondary objectives were to determine the interobserver agreement on the assessment of joint congruity, joint effusion, loose bodies and chondral lesions on conventional MRI. METHODS: Conventional MRIs (1.5 Tesla, elbow specific surface coil) of 30 patients (40...
February 20, 2017: BMC Musculoskeletal Disorders
https://www.readbyqxmd.com/read/28216453/quantification-of-myocardial-oxygenation-in-heart-failure-using-blood-oxygen-level-dependent-t2-magnetic-resonance-imaging-comparison-with-cardiopulmonary-exercise-test
#2
Michinobu Nagao, Yuzo Yamasaki, Satoshi Kawanami, Takeshi Kamitani, Koji Sagiyama, Taiki Higo, Tomomi Ide, Atsushi Takemura, Umiko Ishizaki, Kenji Fukushima, Yuji Watanabe, Hiroshi Honda
PURPOSE: Quantification of myocardial oxygenation (MO) in heart failure (HF) has been less than satisfactory. This has necessitated the use of invasive techniques to measure MO directly or to determine the oxygen demand during exercise using the cardiopulmonary exercise (CPX) test. We propose a new quantification method for MO using blood-oxygen-level-dependent (BOLD) myocardial T2* magnetic resonance imaging (M-T2* MRI), and investigate its correlation with CPX results. METHODS: Thirty patients with refractory HF who underwent cardiac MRI and CPX test for heart transplantation, and 24 healthy, age-matched volunteers as controls were enrolled...
February 16, 2017: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/28191681/a-time-efficient-acquisition-protocol-for-multipurpose-diffusion-weighted-microstructural-imaging-at-7-tesla
#3
Farshid Sepehrband, Kieran O'Brien, Markus Barth
PURPOSE: Several diffusion-weighted MRI techniques have been developed and validated during the past 2 decades. While offering various neuroanatomical inferences, these techniques differ in their proposed optimal acquisition design, preventing clinicians and researchers benefiting from all potential inference methods, particularly when limited time is available. This study reports an optimal design that enables for a time-efficient diffusion-weighted MRI acquisition scheme at 7 Tesla...
February 12, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28178670/new-in-vivo-avatars-of-diffuse-intrinsic-pontine-gliomas-dipg-from-stereotactic-biopsies-performed-at-diagnosis
#4
Alexandre Plessier, Ludivine Le Dret, Pascale Varlet, Kévin Beccaria, Joëlle Lacombe, Sébastien Mériaux, Françoise Geffroy, Laurence Fiette, Patricia Flamant, Fabrice Chrétien, Thomas Blauwblomme, Stéphanie Puget, Jacques Grill, Marie-Anne Debily, David Castel
Diffuse Instrinsic Pontine Glioma is the most aggressive form of High Grade Gliomas in children. The lack of biological material and the absence of relevant models have hampered the development of new therapeutics. Their extensive infiltration of the brainstem renders any surgical resection impossible and until recently biopsies were considered not informative enough and therefore not recommended. Thus, most models were derived from autopsy material. We aimed to develop relevant in vivo DIPG models that mimic this specific disease and its molecular diversity from tumor material obtained at diagnosis...
February 2, 2017: Oncotarget
https://www.readbyqxmd.com/read/28164366/ultralow-field-and-spin-locking-relaxation-dispersion-in-postmortem-pig-brain
#5
Hui Dong, Seong-Min Hwang, Michael Wendland, Lixing You, John Clarke, Ben Inglis
PURPOSE: To investigate tissue-specific differences, a quantitative comparison was made between relaxation dispersion in postmortem pig brain measured at ultralow fields (ULF) and spin locking at 7 tesla (T). The goal was to determine whether ULF-MRI has potential advantages for in vivo human brain imaging. METHODS: Separate specimens of gray matter and white matter were investigated using an ULF-MRI system with superconducting quantum interference device (SQUID) signal detection to measure T1ULF at fields from 58...
February 5, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28152266/bold-fmri-with-median-nerve-electrical-stimulation-predict-hemodynamic-improvement-after-revascularization-in-patients-with-moyamoya-disease
#6
Peng-Gang Qiao, Cong Han, Tianyi Qian, Gong-Jie Li, Hong Yin
PURPOSE: To assess the severity of cerebral hemodynamic impairment and hemodynamic improvements, after revascularization in moyamoya disease (MMD) by means of blood-oxygen-level dependent functional magnetic resonance imaging (BOLD-fMRI). MATERIALS AND METHODS: BOLD-fMRI with median nerve electrical stimulation based on echo planar imaging was performed in 73 volunteers with MMD and 15 healthy volunteers using a 3.0 Tesla MRI scanner. Twenty-four MMD patients were reexamined after encephaloduroarteriosynangiosis...
February 2, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28151553/meta-analysis-of-dorsolateral-nigral-hyperintensity-on-magnetic-resonance-imaging-as-a-marker-for-parkinson-s-disease
#7
Philipp Mahlknecht, Florian Krismer, Werner Poewe, Klaus Seppi
BACKGROUND: Dorsolateral nigral hyperintensity on iron-sensitive magnetic resonance imaging (MRI) sequences seems to be a typical finding in Parkinson's disease (PD), but most studies have involved small samples and have had heterogeneous control populations. OBJECTIVES: The objective of this study was to perform a meta-analysis on dorsolateral nigral hyperintensity as an imaging marker for PD. METHODS: The methods included a systematic literature search and a hierarchical summary receiver operating characteristics curve approach...
February 2, 2017: Movement Disorders: Official Journal of the Movement Disorder Society
https://www.readbyqxmd.com/read/28143419/t2-relaxation-time-for-intervertebral-disc-degeneration-in-patients-with-upper-back-pain-initial-results-on-the-clinical-use-of-3-0-tesla-mri
#8
Raoying Xie, Linhui Ruan, Lei Chen, Kai Zhou, Jiandong Yuan, Wei Ji, Guangjian Jing, Xiaojing Huang, Qinglei Shi, Chun Chen
BACKGROUND: Magnetic resonance imaging (MRI) is a useful non-invasive tool for evaluating abnormalities of intervertebral discs. However, there are few studies which applied functional MRI techniques to investigate degenerative changes in cervical and cervicothoracic junction (CTJ) spine among adults. The aim of this study was to compare T2 relaxation time measurement evaluation with morphological grading for assessing cervical and CTJ intervertebral discs (IVD) in the patients suffering neck, shoulder, and upper back pain...
January 31, 2017: BMC Medical Imaging
https://www.readbyqxmd.com/read/28128022/different-types-of-white-matter-hyperintensities-in-cadasil-insights-from-7-tesla-mri
#9
François De Guio, Alexandre Vignaud, Hugues Chabriat, Eric Jouvent
In Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL), by contrast to sporadic cerebral small vessel disease related to age and hypertension, white matter hyperintensities (WMH) are frequently observed in the white matter of anterior temporal poles, external capsules, and superior frontal regions. Whether these WMH (specific WMH) differ from those observed in other white matter areas (nonspecific WMH) remains unknown. Twenty patients were scanned to compare specific and nonspecific WMH using high-resolution images and analyses of relaxation times (T1R: longitudinal relaxation time and T2*R: effective transversal relaxation time)...
January 1, 2017: Journal of Cerebral Blood Flow and Metabolism
https://www.readbyqxmd.com/read/28123969/real-time-magnetic-resonance-imaging-of-deep-venous-flow-during-muscular-exercise-preliminary-experience
#10
Arun Antony Joseph, Klaus-Dietmar Merboldt, Dirk Voit, Johannes Dahm, Jens Frahm
BACKGROUND: The accurate assessment of peripheral venous flow is important for the early diagnosis and treatment of disorders such as deep-vein thrombosis (DVT) which is a major cause of post-thrombotic syndrome or even death due to pulmonary embolism. The aim of this work is to quantitatively determine blood flow in deep veins during rest and muscular exercise using a novel real-time magnetic resonance imaging (MRI) method for velocity-encoded phase-contrast (PC) MRI at high spatiotemporal resolution...
December 2016: Cardiovascular Diagnosis and Therapy
https://www.readbyqxmd.com/read/28115738/glutamate-imaging-glucest-reveals-lower-brain-glucest-contrast-in-patients-on-the-psychosis-spectrum
#11
D R Roalf, R P R Nanga, P E Rupert, H Hariharan, M Quarmley, M E Calkins, E Dress, K Prabhakaran, M A Elliott, P J Moberg, R C Gur, R E Gur, R Reddy, B I Turetsky
Psychosis commonly develops in adolescence or early adulthood. Youths at clinical high risk (CHR) for psychosis exhibit similar, subtle symptoms to those with schizophrenia (SZ). Malfunctioning neurotransmitter systems, such as glutamate, are implicated in the disease progression of psychosis. Yet, in vivo imaging techniques for measuring glutamate across the cortex are limited. Here, we use a novel 7 Tesla MRI glutamate imaging technique (GluCEST) to estimate changes in glutamate levels across cortical and subcortical regions in young healthy individuals and ones on the psychosis spectrum...
January 24, 2017: Molecular Psychiatry
https://www.readbyqxmd.com/read/28114009/a-new-variational-method-for-bias-correction-and-its-applications-to-rodent-brain-extraction
#12
Huibin Chang, Weimin Huang, Chunlin Wu, Su Huang, Cuntai Guan, Sakthivel Sekar, Kishore Bhakoo, Yuping Duan
Brain extraction is an important preprocessing step for further analysis of brain MR images. Significant intensity inhomogeneity can be observed in rodent brain images due to the high-field MRI technique. Unlike most existing brain extraction methods that require bias corrected MRI, we present a high-order and L0 regularized variational model for bias correction and brain extraction. The model is composed of a data fitting term, a piecewise constant regularization and a smooth regularization, which is constructed on a 3-D formulation for medical images with anisotropic voxel sizes...
December 5, 2016: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28112824/in-vivo-imaging-of-electrical-properties-of-an-animal-tumor-model-with-an-8-channel-transceiver-array-at-7%C3%A2-t-using-electrical-properties-tomography
#13
Jiaen Liu, Qi Shao, Yicun Wang, Gregor Adriany, John Bischof, Pierre-Francois Van de Moortele, Bin He
PURPOSE: To develop and evaluate a technique for imaging electrical properties ((EPs), conductivity and permittivity) of an animal tumor model in vivo using MRI. METHODS: Electrical properties were reconstructed from the calculated EP gradient, which was derived using two sets of measured transmit B1 magnitude and relative phase maps with the sample and radiofrequency (RF) coil oriented in the positive and negative z-directions, respectively. An eight-channel transceiver microstrip array RF coil fitting the size of the animal was developed for generating and mapping B1 fields to reconstruct EPs...
January 23, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28106942/assessment-of-intracranial-meningioma-associated-calcifications-using-susceptibility-weighted-mri
#14
Lisa C Adams, Sarah M Böker, Yvonne Y Bender, Eva M Fallenberg, Moritz Wagner, Ralph Buchert, Bernd Hamm, Marcus R Makowski
PURPOSE: To determine the diagnostic accuracy of susceptibility-weighted MRI (SW-MRI) for the detection of intracranial meningioma-associated calcifications compared with standard MR sequences, using computed tomography (CT) as a reference standard. MATERIALS AND METHODS: 354 patients, who had received both a CT and a 1.5 Tesla clinical brain MRI with SW-MRI sequences between January 2014 and July 2016, were retrospectively evaluated and 316 patients were included...
January 20, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28106936/whole-brain-vessel-wall-mri-a-parameter-tune-up-solution-to-improve-the-scan-efficiency-of-three-dimensional-variable-flip-angle-turbo-spin-echo
#15
Qi Yang, Zixin Deng, Xiaoming Bi, Shlee S Song, Konrad H Schlick, Nestor R Gonzalez, Debiao Li, Zhaoyang Fan
PURPOSE: To propose and evaluate a parameter tune-up solution to expedite a three-dimensional (3D) variable-flip-angle turbo spin-echo (TSE) sequence for whole-brain intracranial vessel wall (IVW) imaging. MATERIALS AND METHODS: Elliptical k-space sampling and prolonged echo train length (ETL), were used to expedite a 3D variable-flip-angle TSE-based sequence. To compensate for the potential loss in vessel wall signal, optimal combination of prescribed T2 and ETL was experimentally investigated on 22 healthy volunteers at 3 Tesla...
January 20, 2017: Journal of Magnetic Resonance Imaging: JMRI
https://www.readbyqxmd.com/read/28102957/rf-safety-assessment-of-a-bilateral-four-channel-transmit-receive-7-tesla-breast-coil-sar-versus-tissue-temperature-limits
#16
Thomas M Fiedler, Mark E Ladd, Andreas K Bitz
PURPOSE: The purpose of this work was to perform an RF safety evaluation for a bilateral four-channel transmit/receive breast coil and to determine the maximum permissible input power for which RF exposure of the subject stays within recommended limits. The safety evaluation was done based on SAR as well as on temperature simulations. In comparison to SAR, temperature is more directly correlated with tissue damage, which allows a more precise safety assessment. The temperature simulations were performed by applying three different blood perfusion models as well as two different ambient temperatures...
January 2017: Medical Physics
https://www.readbyqxmd.com/read/28090448/quantitative-techniques-for-musculoskeletal-mri-at-7-tesla
#17
REVIEW
Neal K Bangerter, Meredith D Taylor, Grayson J Tarbox, Antony J Palmer, Daniel J Park
Whole-body 7 Tesla MRI scanners have been approved solely for research since they appeared on the market over 10 years ago, but may soon be approved for selected clinical neurological and musculoskeletal applications in both the EU and the United States. There has been considerable research work on musculoskeletal applications at 7 Tesla over the past decade, including techniques for ultra-high resolution morphological imaging, 3D T2 and T2* mapping, ultra-short TE applications, diffusion tensor imaging of cartilage, and several techniques for assessing proteoglycan content in cartilage...
December 2016: Quantitative Imaging in Medicine and Surgery
https://www.readbyqxmd.com/read/28073197/detection-rate-for-significant-cancer-at-confirmatory-biopsy-in-men-enrolled-in-active-surveillance-protocol-20-cores-vs-30-cores-vs-mri-trus-fusion-prostate-biopsy
#18
Pietro Pepe, Sebastiano Cimino, Antonio Garufi, Giandomenico Priolo, Giorgio Ivan Russo, Raimondo Giardina, Giulio Reale, Michele Barbera, Paolo Panella, Michele Pennisi, Giuseppe Morgia
INTRODUCTION: The detection rate for significant prostate cancer of extended vs saturation vs mMRI/TRUS fusion biopsy was prospectively evaluated in men enrolled in active surveillance (AS) protocol. Mterials and methods: From May 2013 to September 2016 75 men aged 66 years (median) with very low risk PCa were enrolled in an AS protocol and elegible criteria were: life expectancy greater than 10 years, cT1C, PSA below 10 ng/ml, PSA density < 0.20, 2 < unilateral positive biopsy cores, Gleason score (GS) equal to 6, greatest percentage of cancer (GPC) in a core < 50%...
December 30, 2016: Archivio Italiano di Urologia, Andrologia
https://www.readbyqxmd.com/read/28048810/su-f-i-25-reproducibility-of-phosphorus-mrs-and-work-measurements-for-evaluating-skeletal-muscle-metabolism
#19
F Settles, E Ripley, D Shengwen, G Clarke
PURPOSE: Skeletal muscle energetics were studied by phosphorus-31 MRS ((31) P-MRS) during exercise. The reproducibility of work performed and the MRS parameters were investigated. METHODS: Reproducibility of the (31) P-MRS exercise parameters was validated in five healthy volunteers (2 M/3 F, age 39.2 ± 21.9 yr, BMI 25.1 ± 4.8 kg/m(2) ). Five minute exercise of the vastus lateralis (VL) was performed on two separate occasions during MRS in a 3 Tesla MRI system...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28046836/we-fg-202-08-assessment-of-treatment-response-via-longitudinal-diffusion-mri-on-a-mri-guided-system-initial-experience-of-quantitative-analysis
#20
X Qi, Y Yang, L Yang, D Low, K Sheng
PURPOSE: To report our initial experience of systematic monitoring treatment response using longitudinal diffusion MR images on a Co-60 MRI-guided radiotherapy system. METHODS: Four patients, including 2 head-and-necks, 1 sarcoma and 1 GBM treated on a 0.35 Tesla MRI-guided treatment system, were analyzed. For each patient, 3D TrueFISP MRIs were acquired during CT simulation and before each treatment for treatment planning and patient setup purposes respectively...
June 2016: Medical Physics
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