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Improved segmentation of deep brain grey matter structures using magnetization transfer (MT) parameter maps

Gunther Helms, Bogdan Draganski, Richard Frackowiak, John Ashburner, Nikolaus Weiskopf
2009 NeuroImage  
We demonstrate improved automated segmentation of putamen, pallidum, pulvinar and substantia nigra using MT images.  ...  Currently available structural T1-weighted (T1w) magnetic resonance images do not provide sufficient contrast for reliable automated segmentation of various subcortical grey matter structures.  ...  To this end, we used parameter maps based on magnetization transfer (MT) contrast.  ... 
doi:10.1016/j.neuroimage.2009.03.053 pmid:19344771 pmcid:PMC2694257 fatcat:odlwvq4ajffj3eo3qqrgv76h3u

Voxel-Based quantitative MRI reveals spatial patterns of grey matter alteration in multiple sclerosis

Emilie Lommers, Camille Guillemin, Gilles Reuter, Eve Fouarge, Gaël Delrue, Fabienne Collette, Christian Degueldre, Evelyne Balteau, Pierre Maquet, Christophe Phillips
2020 Human Brain Mapping  
(qMRI) parameters-magnetization transfer (MT) saturation, longitudinal (R1), and effective transverse (R2*) relaxation rates, derived from data acquired during a single scanning session.  ...  The qMRI maps were computed and segmented in different tissue classes.  ...  Voxel-based analysis of grey matter magnetization transfer ratio maps in early relapsing remitting multiple sclerosis.  ... 
doi:10.1002/hbm.25274 pmid:33155763 pmcid:PMC7856642 fatcat:eshdgoc7rngrpg6uxyjspzzifq

Expanding the clinical phenotypes of MT-ATP6 mutations

Ester López-Gallardo, Sonia Emperador, Abelardo Solano, Laura Llobet, Antonio Martín-Navarro, Manuel José López-Pérez, Paz Briones, Mercedes Pineda, Rafael Artuch, Elena Barraquer, Ivonne Jericó, Eduardo Ruiz-Pesini (+1 others)
2014 Human Molecular Genetics  
To correct this bias, we have performed a screening of the MT-ATP6 gene in a large collection of patients suspected of suffering different mitochondrial DNA (mtDNA) disorders.  ...  Two of them in patients showing phenotypes that have not been commonly associated to mutations in the MT-ATP6 gene.  ...  Computerized tomography scan and magnetic resonance imaging (MRI) showed cerebellum and brainstem atrophy and diffuse increased signal on cerebellar white matter.  ... 
doi:10.1093/hmg/ddu339 pmid:24986921 fatcat:jfg3xhfanbcehetf325i6zxe54

Technical Note: Simultaneous Segmentation and Relaxometry for MRI through Multitask Learning

Peng Cao, Jing liu, Shuyu Tang, Andrew P. Leynes, Janine M. Lupo, Duan Xu, Peder E. Z. Larson
2019 Medical Physics (Lancaster)  
The proposed multitask learning method can directly generate brain apparent T1 and T2 maps, as well as synthetic T1- and T2-weighted images, in conjunction with segmentation of gray matter, white matter  ...  This study demonstrated a magnetic resonance (MR) signal multitask learning method for three-dimensional (3D) simultaneous segmentation and relaxometry of human brain tissues.  ...  results in general, with slightly improved gray matter separation in the cortex (arrows in Fig. 6 ); while FAST is better at some deep brain structures, i.e., putamen and the head of caudate.  ... 
doi:10.1002/mp.13756 pmid:31396973 pmcid:PMC6800607 fatcat:eyvagxub4fby7m2xq2rrjxledi

Synthetic quantitative MRI through relaxometry modelling

Martina F. Callaghan, Siawoosh Mohammadi, Nikolaus Weiskopf
2016 NMR in Biomedicine  
The synthetic MT map is shown to provide improved segmentation of deep grey matter structures, relative to segmentation using T 1 -weighted images or R 1 maps.  ...  In the second application, a map of magnetization transfer (MT) saturation is synthesized without the need to acquire an MT-weighted volume, which directly leads to a reduction in the specific absorption  ...  improved segmentation of deep grey matter (GM) structures. 12 These segmentation benefits are of great clinical importance because changes in regions such as the basal ganglia are associated with a  ... 
doi:10.1002/nbm.3658 pmid:27753154 pmcid:PMC5132086 fatcat:gdeqyoesdbgh5ib77hn7yfpldm

Regional specificity of MRI contrast parameter changes in normal ageing revealed by voxel-based quantification (VBQ)

B. Draganski, J. Ashburner, C. Hutton, F. Kherif, R.S.J. Frackowiak, G. Helms, N. Weiskopf
2011 NeuroImage  
Using a whole-brain approach in a cohort of 26 adults, aged 18-85 years, we performed voxel-based morphometric (VBM) analysis and voxel-based quantification (VBQ) of diffusion tensor, magnetization transfer  ...  (MT), R1, and R2* relaxation parameters.  ...  We took advantage of a more reliable characterisation of subcortical structures based on automated tissue classification using MT maps with exquisite contrast between GM and WM in deep brain regions .  ... 
doi:10.1016/j.neuroimage.2011.01.052 pmid:21277375 pmcid:PMC3093621 fatcat:ff53tqdqdbhp7a4vuozx77gr3e

Mt Everest trek causes impaired cardiac high energy phosphate metabolism and diastolic impairment

Cameorn J Holloway, Andrew Murray, Lowri E Cochlin, Yaso Emmanuel, Denny ZH Levett, Oliver J Rider, Damian J Tyler, Matthew Robson, Jane M Francis, Hugh Montgomery, Michael PW Grocott, Stefan Neubauer (+1 others)
2009 Journal of Cardiovascular Magnetic Resonance  
The use of ICDs in this large patient population is still limited by high costs and possible adverse events including inappropriate discharges and progression of heart failure.  ...  Journal of Cardiovascular Magnetic Resonance 2009, 11(Suppl 1):O1 Introduction: Prophylactic implantation of a cardioverter/ defibrillator (ICD) has been shown to reduce mortality in patients with chronic  ...  Conclusion: We presented a robust, accurate and efficient method for the fully automatic delineation of the myocardium contours in LA + SA cine CMR images, which can be used for accurate LV functional  ... 
doi:10.1186/1532-429x-11-s1-o6 fatcat:d7ji776ko5ahvewxejrzp5uew4

Whole brain and deep gray matter structure segmentation: Quantitative comparison between MPRAGE and MP2RAGE sequences

Amgad Droby, Avner Thaler, Nir Giladi, R. Matthew Hutchison, Anat Mirelman, Dafna Ben Bashat, Moran Artzi, Joseph Najbauer
2021 PLoS ONE  
Objective T1-weighted MRI images are commonly used for volumetric assessment of brain structures.  ...  This study aimed to quantitatively assess the agreement of whole brain tissue and deep GM (DGM) volumes obtained from MP2RAGE compared to the widely used MP-RAGE sequence.  ...  This can be achieved mainly by segmenting the brain structures based on T1-weighted, T2-weighted, proton density (PD), magnetic transfer (MT), or multi-contrasts [3, 4] .  ... 
doi:10.1371/journal.pone.0254597 pmid:34358242 pmcid:PMC8345829 fatcat:cfihzqdrwrekrnvthdy6shydby

Brain and Spinal Cord MRI in Multiple Sclerosis: an Update

Mike Wattjes, Peter Raab
2017 Neurology International Open  
Quantitative MRI methods and ultra-high-field MRI offer the opportunity for the quantitative assessment of damage in normal-appearing brain tissue.  ...  However, the standardization of these techniques with the goal of implementation in clinical routine will be one of the major challenges in the near future.  ...  Conflict of interest M. P. Wattjes received consultancy and speaking fees from Biogen, Genzyme, IXICO, Novartis, Roche. P. Raab has nothing to disclose.  ... 
doi:10.1055/s-0043-118111 fatcat:4db5qma5gnakdidzen24wa7oou

Studying cyto and myeloarchitecture of the human cortex at ultra-high field with quantitative imaging: R 1 , R 2 * and magnetic susceptibility

José P. Marques, Diana Khabipova, Rolf Gruetter
2017 NeuroImage  
While both R 1 and R 2 * maps decrease monotonically from the white matter to the pial surface due to the decrease of myelin and iron between these regions, magnetic susceptibility maps have a more complex  ...  regions, suggesting these features could be used for individual cortical brain parcellation.  ...  The authors would like to thank Daniel Gallichan for sequence development support, Tim van Mourik for providing the software to calculate equi-volume depth segmentation of the cortical maps, Jonathan Polimeni  ... 
doi:10.1016/j.neuroimage.2016.12.009 pmid:27939794 fatcat:st7wxajt6rf7ffecu5c2wfco5y

Flexible proton density (PD) mapping using multi-contrast variable flip angle (VFA) data

Sara Lorio, Tim M. Tierney, Amy McDowell, Owen J. Arthurs, Antoine Lutti, Nikolaus Weiskopf, David W. Carmichael
2019 NeuroImage  
The multi-contrast PD values homogeneity and accuracy within the cerebrospinal fluid (CSF) and deep brain structures are increased beyond that obtained using PD* maps.  ...  within tissue class of the final map.  ...  Aiming to utilise all available data, we employed all the contrasts for the PD map estimation including the magnetization transfer (MT) weighted scan in the MPM protocol.  ... 
doi:10.1016/j.neuroimage.2018.11.023 pmid:30465865 pmcid:PMC7611405 fatcat:t3vdexztkfhujmrp6akieqrneq

Childhood socio‐economic disadvantage predicts reduced myelin growth across adolescence and young adulthood

Gabriel Ziegler, Michael Moutoussis, Tobias U. Hauser, Pasco Fearon, Edward T. Bullmore, Ian M. Goodyer, Peter Fonagy, Peter B. Jones, Ulman Lindenberger, Raymond J. Dolan
2020 Human Brain Mapping  
This association was observed for magnetization transfer in cortical, subcortical and core white matter regions, and also in key subcortical nuclei.  ...  (MT), a myelin-sensitive marker, in 288 participants (149 female) between 14 and 25 years of age at baseline.  ...  For this purpose, we used nonlinear registration to obtain normalised (grey and white matter) tissue segment maps using both within-and between-subjects modulation.  ... 
doi:10.1002/hbm.25024 pmid:32432383 pmcid:PMC7375075 fatcat:x6vpq7t7fbgbhppwy44rsskcim

hMRI – A toolbox for quantitative MRI in neuroscience and clinical research

Karsten Tabelow, Evelyne Balteau, John Ashburner, Martina F. Callaghan, Bogdan Draganski, Gunther Helms, Ferath Kherif, Tobias Leutritz, Antoine Lutti, Christophe Phillips, Enrico Reimer, Lars Ruthotto (+4 others)
2019 NeuroImage  
) that can be used for quantitative parameter analysis and accurate delineation of subcortical brain structures.  ...  This toolbox allows the estimation of high-quality multi-parameter qMRI maps (longitudinal and effective transverse relaxation rates R1 and R2⋆, proton density PD and magnetisation transfer MT saturation  ...  (2009) _ _ ✓ MT 49 C Improved segmentation of deep brain grey matter structures using magnetisation transfer saturation (MT) parameter maps.  ... 
doi:10.1016/j.neuroimage.2019.01.029 pmid:30677501 pmcid:PMC6547054 fatcat:6m7s4t2vajhshgybudevhuh3bi

Monitoring Progressive Multiple Sclerosis with Novel Imaging Techniques

Maria Petracca, Monica Margoni, Giulia Bommarito, Matilde Inglese
2018 Neurology and Therapy  
Advanced imaging techniques that have the advantage of metrics with increased sensitivity to short-term tissue changes and increased specificity to the structural abnormalities characteristic of PMS have  ...  magnetic resonance imaging techniques and (3) discuss recent advancements and future perspectives in monitoring PMS with imaging techniques.  ...  Advanced MRI Techniques Magnetization Transfer imaging Magnetization transfer (MT) MRI provides an index, called the MT ratio (MTR), whose values reflect the efficiency of the magnetization exchange between  ... 
doi:10.1007/s40120-018-0103-2 pmid:29956263 fatcat:5atggmvtjredddx237lqlkwejq

Neuroimaging Correlates of Cognitive Dysfunction in Adults with Multiple Sclerosis

Maria Petracca, Giuseppe Pontillo, Marcello Moccia, Antonio Carotenuto, Sirio Cocozza, Roberta Lanzillo, Arturo Brunetti, Vincenzo Brescia Morra
2021 Brain Sciences  
Cognitive impairment is a frequent and meaningful symptom in multiple sclerosis (MS), caused by the accrual of brain structural damage only partially counteracted by effective functional reorganization  ...  correlates of cognitive impairment in adults with MS, focusing on the mechanisms sustaining damage accrual and on the identification of useful imaging markers of cognitive decline.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/brainsci11030346 pmid:33803287 fatcat:4jfvrxiabvcitifwvhosdkdggm
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