Read by QxMD icon Read

"magnetization transfer"

Linda I Suleiman, Kenneth A Weber, Brett D Rosenthal, Surabhi A Bhatt, Jason W Savage, Wellington K Hsu, Alpesh A Patel, Todd B Parrish
Magnetization transfer (MT) contrast has been established as a marker of myelin integrity, and cervical spondylotic myelopathy is known to cause demyelination. Ten patients with clinical and magnetic resonance imaging (MRI) manifestations of cervical spondylotic myelopathy (CSM) were compared to the MRIs of seven historic healthy controls, using the magnetization transfer ratio (MTR) and Nurick scores as the primary metrics. Transverse slices through the intervertebral discs of the cervical spine were acquired using a gradient echo sequence (MEDIC) with and without an MT saturation pulse on a 3 Tesla Siemens Prisma scanner (TR = 300 ms, TEeff  = 17 ms, flip angle = 30°, in-plane resolution = 0...
March 9, 2018: Journal of Clinical Neuroscience: Official Journal of the Neurosurgical Society of Australasia
Tina Roostaei, Shokufeh Sadaghiani, Rahil Mashhadi, Masih Falahatian, Esmaeil Mohamadi, Nina Javadian, Aria Nazeri, Rozita Doosti, Abdorreza Naser Moghadasi, Mahsa Owji, Amir Pejman Hashemi Taheri, Ali Shakouri Rad, Amirreza Azimi, Aristotle N Voineskos, Arash Nazeri, Mohammad Ali Sahraian
BACKGROUND: Complement system activation products are present in areas of neuroinflammation, demyelination, and neurodegeneration in brains of patients with multiple sclerosis (MS). C3 is a central element in the activation of complement cascades. A common coding variant in the C3 gene (rs2230199, C3R102G) affects C3 activity. OBJECTIVES: To assess the effects of rs2230199 on MS severity using clinical, cognitive, and imaging measures. METHODS: In total, 161 relapse-onset MS patients (Expanded Disability Status Scale (EDSS) ≤ 6) underwent physical assessments, cognitive tests (Paced Auditory Serial Addition Test (PASAT), Symbol Digit Modalities Test (SDMT), and California Verbal Learning Test (CVLT)), and magnetic resonance imaging (MRI)...
February 1, 2018: Multiple Sclerosis: Clinical and Laboratory Research
Kyle M Jones, Carol A Stuehm, Charles C Hsu, Phillip H Kuo, Mark D Pagel, Edward A Randtke
Performing chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) in lung tissue is difficult because of motion artifacts. We, therefore, developed a CEST MRI acquisition and analysis method that performs retrospective respiration gating. Our method used an acquisition scheme with a short 200-millisecond saturation pulse that can accommodate the timing of the breathing cycle, and with saturation applied at frequencies in 0.03-ppm intervals. The Fourier transform of each image was used to calculate the difference in phase angle between adjacent pixels in the longitudinal direction of the respiratory motion...
December 2017: Tomography: a Journal for Imaging Research
E Van Obberghen, S Mchinda, A le Troter, V H Prevost, P Viout, M Guye, G Varma, D C Alsop, J-P Ranjeva, J Pelletier, O Girard, G Duhamel
BACKGROUND AND PURPOSE: Inhomogeneous magnetization transfer is a new endogenous MR imaging contrast mechanism that has demonstrated high specificity for myelin. Here, we tested the hypothesis that inhomogeneous magnetization transfer is sensitive to pathology in a population of patients with relapsing-remitting MS in a way that both differs from and complements conventional magnetization transfer. MATERIALS AND METHODS: Twenty-five patients with relapsing-remitting MS and 20 healthy volunteers were enrolled in a prospective MR imaging research study, whose protocol included anatomic imaging, standard magnetization transfer, and inhomogeneous magnetization transfer imaging...
February 22, 2018: AJNR. American Journal of Neuroradiology
Jennifer Kollmer, Thorsten Kästel, Johann M E Jende, Martin Bendszus, Sabine Heiland
BACKGROUND AND PURPOSE: Magnetization transfer contrast imaging provides indirect information on the concentration of "bound" water protons and their interactions with "free" water molecules. The purpose of this study is to analyze location- and age-dependent changes in the magnetization transfer ratio (MTR) of lower extremity nerves. MATERIALS AND METHODS: Ten younger (20-32 years) and 5 older (50-63 years) healthy volunteers underwent magnetization transfer contrast imaging at 3 Tesla Two 3-dimensional gradient echo sequences with and without an off-resonance saturation pulse (repetition time: 58 milliseconds; echo time: 2...
February 21, 2018: Investigative Radiology
Inês Pita, Fernando Magro
Treatment of Crohn's disease (CD) is intrinsically reliant on imaging techniques, due to the preponderance of small bowel disease and its transmural pattern of inflammation. Ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) are the most widely employed imaging methods and have excellent diagnostic accuracy in most instances. Some limitations persist, perhaps the most clinically relevant being the distinction between inflammatory and fibrotic strictures. In this regard, several methodologies have recently been tested in animal models and human patients, namely US strain elastography, shear wave elastography, contrast-enhanced US, magnetization transfer MRI and contrast dynamics in standard MRI...
2018: Therapeutic Advances in Gastroenterology
Christian Eberhardt, Moritz C Wurnig, Andrea Wirsching, Cristina Rossi, Idana Feldmane, Mickael Lesurtel, Andreas Boss
This study aimed to monitor the course of liver regeneration by multiparametric magnetic-resonance imaging (MRI) after partial liver resection characterizing Small-for-Size Syndrome (SFSS), which frequently leads to fatal post-hepatectomy liver failure (PLF). Twenty-two C57BL/6 mice underwent either conventional 70% partial hepatectomy (cPH), extended 86% partial hepatectomy (ePH) or SHAM operation. Subsequent MRI scans on days 0, 1, 2, 3, 5 and 7 in a 4.7T MR Scanner quantified longitudinal and transverse relaxation times, apparent diffusion coefficient (ADC) and the magnetization-transfer ratio (MTR) of the regenerating liver parenchyma...
2018: PloS One
Zhongliang Zu, Aqeela Afzal, Hua Li, Jingping Xie, John C Gore
We have previously reported that the dispersion of spin-lattice relaxation rates in the rotating frame (R1ρ ) of tissue water protons at high field can be dominated by chemical exchange contributions. Ischemia in brain causes changes in tissue pH, which in turn may affect proton exchange rates. Amide proton transfer (APT, a form of chemical exchange saturation transfer) has been shown to be sensitive to chemical exchange rates and able to detect pH changes non-invasively following ischemic stroke. However, the specificity of APT to pH changes is decreased because of the influence of several other factors that affect magnetization transfer...
February 9, 2018: NMR in Biomedicine
Hatef Mehrabian, Sten Myrehaug, Hany Soliman, Arjun Sahgal, Greg J Stanisz
Quantitative magnetization transfer (qMT) was used as a biomarker to monitor glioblastoma (GBM) response to chemo-radiation and identify the earliest time-point qMT could differentiate progressors from non-progressors. Nineteen GBM patients were recruited and MRI-scanned before (Day0), two weeks (Day14), and four weeks (Day28) into the treatment, and one month after the end of the treatment (Day70). Comprehensive qMT data was acquired, and a two-pool MT model was fit to the data. Response was determined at 3-8 months following the end of chemo-radiation...
February 6, 2018: Scientific Reports
Ivan Luptak, Aaron L Sverdlov, Marcello Panagia, Fuzhong Qin, David R Pimentel, Dominique Croteau, Deborah A Siwik, Joanne S Ingwall, Markus M Bachschmid, James A Balschi, Wilson S Colucci
Metabolic syndrome is a cluster of obesity-related metabolic abnormalities that lead to metabolic heart disease (MHD) with left ventricular pump dysfunction. Although MHD is thought to be associated with myocardial energetic deficiency, two key questions have not been answered. First, it is not known whether there is a sufficient energy deficit to contribute to pump dysfunction. Second, the basis for the energy deficit is not clear. To address these questions, mice were fed a high fat, high sucrose (HFHS) 'Western' diet to recapitulate the MHD phenotype...
January 31, 2018: Journal of Molecular and Cellular Cardiology
Lin Chen, Xiang Xu, Haifeng Zeng, Kannie W Y Chan, Nirbhay Yadav, Shuhui Cai, Kathryn J Schunke, Nauder Faraday, Peter C M van Zijl, Jiadi Xu
PURPOSE: To develop a method that can separate and quantify the fast (>1 kHz) and slow exchange transfer and magnetization transfer components in Z-spectra. METHODS: Z-spectra were recorded as a function of mixing time using a train of selective pulses providing variable-delay multipulse build-up curves. Fast and slow transfer components in the Z-spectra were separated and quantified on a voxel-by-voxel basis by fitting the mixing time-dependent CEST signal using a 3-pool model...
February 5, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Federica Agosta, Edoardo Gioele Spinelli, Ivan V Marjanovic, Zorica Stevic, Elisabetta Pagani, Paola Valsasina, Biljana Salak-Djokic, Milena Jankovic, Dragana Lavrnic, Vladimir S Kostic, Massimo Filippi
OBJECTIVE: To explore structural and functional changes of the brain and cervical cord in patients with amyotrophic lateral sclerosis (ALS) due to mutation in the superoxide dismutase (SOD1) gene compared with sporadic ALS. METHODS: Twenty patients with SOD1 ALS, 11 with sporadic ALS, and 33 healthy controls underwent clinical evaluation and brain MRI. Cortical thickness analysis, diffusion tensor MRI of the corticospinal tracts (CST) and corpus callosum, and resting-state functional connectivity were performed...
January 24, 2018: Neurology
Jacqueline Chen, Volodymyr Kostenko, Erik P Pioro, Bruce D Trapp
Purpose To determine if magnetic resonance (MR) imaging metrics can estimate primary motor cortex (PMC) motor neuron (MN) density in patients with amyotrophic lateral sclerosis (ALS). Materials and Methods Between 2012 and 2014, in situ brain MR imaging was performed in 11 patients with ALS (age range, 35-81 years; seven women and four men) soon after death (mean, 5.5 hours after death; range, 3.2-9.6 hours). The brain was removed, right PMC (RPMC) was excised, and MN density was quantified. RPMC metrics (thickness, volume, and magnetization transfer ratio) were calculated from MR images...
January 23, 2018: Radiology
Paula Alcaide-Leon, Kateryna Cybulsky, Stephanie Sankar, Courtney Casserly, General Leung, Marika Hohol, Daniel Selchen, Xavier Montalban, Aditya Bharatha, Jiwon Oh
Objectives: To assess whether quantitative spinal cord MRI (SC-MRI) measures, including atrophy, and diffusion tensor imaging (DTI) and magnetization transfer imaging metrics were different in radiologically isolated syndrome (RIS) vs healthy controls (HCs). Methods: Twenty-four participants with RIS and 14 HCs underwent cervical SC-MRI on a 3T magnet. Manually segmented regions of interest circumscribing the spinal cord cross-sectional area (SC-CSA) between C3 and C4 were used to extract SC-CSA, fractional anisotropy, mean, perpendicular, and parallel diffusivity (MD, λ⊥, and λ||) and magnetization transfer ratio (MTR)...
March 2018: Neurology® Neuroimmunology & Neuroinflammation
Xue-Hua Li, Ren Mao, Si-Yun Huang, Can-Hui Sun, Qing-Hua Cao, Zhuang-Nian Fang, Zhong-Wei Zhang, Li Huang, Jin-Jiang Lin, Yu-Jun Chen, Jordi Rimola, Florian Rieder, Min-Hu Chen, Shi-Ting Feng, Zi-Ping Li
Purpose To evaluate the role of magnetization transfer (MT) magnetic resonance (MR) imaging for the characterization of intestinal fibrosis compared with contrast material-enhanced and diffusion-weighted MR imaging and its capability for differentiating fibrotic from inflammatory strictures in humans with Crohn disease (CD) by using surgical histopathologic analysis as the reference standard. Materials and Methods Institutional review board approval and informed consent were obtained for this prospective study...
January 19, 2018: Radiology
Jiaxuan Zhang, Wenzhen Zhu, Rongwen Tain, Xiaohong Joe Zhou, Kejia Cai
PURPOSE: The purpose of the study is to demonstrate the value of quantitative amide proton transfer (APT) imaging for differentiating glioma grades and detecting tumor proliferation. PROCEDURES: This study included 32 subjects with 16 low-grade gliomas (LGG) and 16 high-grade gliomas (HGG) confirmed by histopathology. Chemical exchange saturation transfer (CEST) magnetic resonance imaging with APT weighting was performed on a 3 T scanner. After B0 correction, Z-spectra were fitted with Lorentzian functions corresponding to the upfield semi-solid magnetization transfer and nuclear overhauser enhancement (MT&NOE) effect, the direct saturation (DS) effect, and the downfield APT effect centered at around - 1...
January 8, 2018: Molecular Imaging and Biology: MIB: the Official Publication of the Academy of Molecular Imaging
Yuchi Liu, Yuning Gu, Xin Yu
Many human diseases are caused by an imbalance between energy production and demand. Magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) provide the unique opportunity for in vivo assessment of several fundamental events in tissue metabolism without the use of ionizing radiation. Of particular interest, phosphate metabolites that are involved in ATP generation and utilization can be quantified noninvasively by phosphorous-31 (31P) MRS/MRI. Furthermore, 31P magnetization transfer (MT) techniques allow in vivo measurement of metabolic fluxes via creatine kinase (CK) and ATP synthase...
December 2017: Quantitative Imaging in Medicine and Surgery
Catherine Lebel, Sean Deoni
Throughout infancy, childhood, and adolescence, our brains undergo remarkable changes. Processes including myelination and synaptogenesis occur rapidly across the first 2-3 years of life, and ongoing brain remodeling continues into young adulthood. Studies have sought to characterize the patterns of structural brain development, and early studies predominately relied upon gross anatomical measures of brain structure, morphology, and organization. MRI offers the ability to characterize and quantify a range of microstructural aspects of brain tissue that may be more closely related to fundamental neurodevelopmental processes...
January 3, 2018: NeuroImage
Gaetano Perrotta, Guillaume Bonnier, Djalel-Eddine Meskaldji, David Romascano, Ruslan Aydarkhanov, Alessandro Daducci, Samanta Simioni, Matthias Cavassini, Melanie Metral, François Lazeyras, Reto Meuli, Gunnar Krueger, Renaud A Du Pasquier, Cristina Granziera
Rivastigmine has been shown to improve cognition in HIV+ patients with minor neurocognitive disorders; however, the mechanisms underlying such beneficial effect are currently unknown. To assess whether rivastigmine therapy is associated with decreased brain inflammation and damage, we performed T1/T2* relaxometry and magnetization transfer imaging in 17 aviremic HIV+ patients with minor neurocognitive disorders enrolled on a crossed over randomized rivastigmine trial. Rivastigmine therapy was associated with changes in MRI metrics indicating a decrease in brain water content (i...
December 2017: Annals of Clinical and Translational Neurology
Christos G Xanthis, Sebastian Bidhult, Andreas Greiser, Kelvin Chow, Richard B Thompson, Håkan Arheden, Anthony H Aletras
Quantitative cardiovascular Magnetic Resonance Imaging techniques are gaining wide acceptance within the MR community due to their potential to diagnose non-localized disease, guide therapy and improve patient outcome. During the last decade, there has been an increasing interest for developing new techniques that allow for simultaneous quantification of both T1 and T2 maps of myocardium. Newer studies demonstrated that the incorporation of MRI simulations could yield similar results to conventional mapping techniques in the myocardium...
December 26, 2017: Magnetic Resonance Imaging
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"