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Simulated Field Maps: Toward Improved Susceptibility Artefact Correction in Interventional MRI [chapter]

Martin Kochan, Pankaj Daga, Ninon Burgos, Mark White, M. Jorge Cardoso, Laura Mancini, Gavin P. Winston, Andrew W. McEvoy, John Thornton, Tarek Yousry, John S. Duncan, Danail Stoyanov (+1 others)
2014 Lecture Notes in Computer Science  
In this paper, we propose a novel method for simulating main magnetic field inhomogeneity maps during intraoperative MRI-guided neurosurgery.  ...  We find a close agreement between the field inhomogeneity maps acquired as part of the imaging protocol and the simulated field inhomogeneity maps generated by the proposed method.  ...  This work was supported by the UCL Doctoral Training Programme in Medical and Biomedical Imaging studentship funded by the EPSRC.  ... 
doi:10.1007/978-3-319-07521-1_24 fatcat:tzp2vej2fjck7kxudk6ctwq3fa

Simulated field maps for susceptibility artefact correction in interventional MRI

Martin Kochan, Pankaj Daga, Ninon Burgos, Mark White, M. Jorge Cardoso, Laura Mancini, Gavin P. Winston, Andrew W. McEvoy, John Thornton, Tarek Yousry, John S. Duncan, Danail Stoyanov (+1 others)
2015 International Journal of Computer Assisted Radiology and Surgery  
An existing approach to correct the artefact is to acquire a field map by means of an ad-  ...  Diffusion-weighted MRI (DW-MRI) provides critical information about location, orientation and structure of nerve fibre tracts, but suffers from the "susceptibility artefact" stemming from magnetic field  ...  We find a close agreement between acquired and simulated field maps and observe a statistically significant reduction of the susceptibility artefact in DW-MRI datasets corrected using simulated field maps  ... 
doi:10.1007/s11548-015-1253-7 pmid:26179219 fatcat:t2vci7wtc5ahpn6ew446jdafr4

QSMxT: Robust Masking and Artefact Reduction for Quantitative Susceptibility Mapping [article]

Ashley Wilton Stewart, Simon Daniel Robinson, Kieran O'Brien, Jin Jin, Georg Widhalm, Gilbert Hangel, Angela Walls, Jonathan Goodwin, Korbinian Eckstein, Monique Tourell, Catherine Morgan, Aswin Narayanan (+2 others)
2021 bioRxiv   pre-print
QSMxT is robust across a range of datasets at 3 T in healthy volunteers and phantoms, at 7 T in tumour patients, and in the QSM challenge 2.0 simulated brain dataset, with significant artefact and error  ...  AbstractPurposeQuantitative Susceptibility Mapping (QSM) is a post-processing technique applied to gradient-echo phase data.  ...  Introduction Quantitative Susceptibility Mapping (QSM) is an MRI method that aims to calculate the magnetisation induced in tissues when placed in a magnetic field.  ... 
doi:10.1101/2021.05.05.442850 fatcat:upvjpxwhargdjh76utm4bsewvy

Susceptibility artefact correction using dynamic graph cuts: Application to neurosurgery

Pankaj Daga, Tejas Pendse, Marc Modat, Mark White, Laura Mancini, Gavin P. Winston, Andrew W. McEvoy, John Thornton, Tarek Yousry, Ivana Drobnjak, John S. Duncan, Sebastien Ourselin
2014 Medical Image Analysis  
In this paper, we present a novel method for correction of distortions arising from susceptibility artefacts in EPI images.  ...  is demonstrated on EPI images acquired with an interventional MRI scanner during neurosurgery.  ...  Acknowledgements We are grateful to Wolfson Trust and Epilepsy Society for supporting the Epilepsy Society MRI scanner.  ... 
doi:10.1016/ pmid:25047865 pmcid:PMC6742505 fatcat:fhwo3snw5fhndmox4zavxxqvh4

Quality and denoising in real‐time functional magnetic resonance imaging neurofeedback: A methods review

Stephan Heunis, Rolf Lamerichs, Svitlana Zinger, Cesar Caballero‐Gaudes, Jacobus F. A. Jansen, Bert Aldenkamp, Marcel Breeuwer
2020 Human Brain Mapping  
In this work, we present the first extensive review of acquisition, processing and quality control methods available to improve the quality of the neurofeedback signal.  ...  Advances in rtfMRI-NF research depend on reproducibility of methods and results.  ...  Research goal: The above-mentioned open questions, methodological uncertainties and lack of standardisation should guide efforts to move towards improved reproducibility in the field of fMRI neurofeedback  ... 
doi:10.1002/hbm.25010 pmid:32333624 pmcid:PMC7375116 fatcat:xddngwjzyvea3pobc5i6q6ddp4

Co-registration of CTA coronary artery/vein maps and MR myocardial viability/scar maps for optimized revascularization or resynchronization therapy planning

Thomas P O'Donnell, Engin Dikici, Teresa Swenson, Jean Shaffer, Richard D White
2009 Journal of Cardiovascular Magnetic Resonance  
MRI images were analysed using dedicated software (MASS © , Medis,  ...  in this setting.  ...  Acknowledgements his work was supported in part by grants from the national institute of heart, lung and blood R01HL072704 and R01HL61912, and Donald W. Reynolds Foundation grant.  ... 
doi:10.1186/1532-429x-11-s1-p193 fatcat:pg7jna2nwbaijmyy3sf5pbc3um

MR guidance in radiotherapy

Jan J W Lagendijk, Bas W Raaymakers, Cornelis A T Van den Berg, Marinus A Moerland, Marielle E Philippens, Marco van Vulpen
2014 Physics in Medicine and Biology  
Careful mapping of the magnetic field must be applied to correct these distortions.  ...  These artefacts need to be resolved before MRI can be used to guide radiation delivery as discussed above in section 'MRI simulation'.  ... 
doi:10.1088/0031-9155/59/21/r349 pmid:25322150 fatcat:jlxyfw5l5bgrrjpwygbzqpffb4

Comparison of myocardial infarct size measurements between noncontact mapping and cardiac contrast enhanced MRI

Henning Steen, Frederik Voss, Rüdiger Becker, Hugo A Katus, Evangelos Giannitsis
2009 Journal of Cardiovascular Magnetic Resonance  
Myocardial siderosis is the main cause of morbidity and mortality in thalassaemia major. In the United Kingdom approximately 50% of patients die before reaching 35 years.  ...  T2* CMR can now assess cardiac iron O3 Sub-clinical systolic dysfunction with persistent myocardial edema and inflammation in elite high-endurance athletes with common colds: a cardiovascular magnetic  ...  Conclusion: We have demonstrated a rapid method of T2-mapping for quantitative detection of myocardial edema.  ... 
doi:10.1186/1532-429x-11-s1-p90 fatcat:wvvpqhzxgbb2zmufyiwyhyvszy

MRI-Guided High-Intensity Focused Ultrasound Sonication of Liver and Kidney [chapter]

Baudouin Denis de Senneville, Mario Ries, Lambertus W. Bartels, Chrit T. W. Moonen
2011 Medical Radiology  
MRI guidance of the procedure allows in situ target definition.  ...  In addition, MRI can be used to provide continuous temperature mapping during HIFU for spatial and temporal control of the heating procedure and prediction of the final lesion based on the received thermal  ...  Recent technological improvements, described above, have led to significant improvements in MR temperature mapping of these organs, in motion compensation of the HIFU beam, in intercostal HIFU sonication  ... 
doi:10.1007/174_2011_394 fatcat:r2ktxkenxnht7cpqip2p5rz2du

Motion correction in MRI of the brain

F Godenschweger, U Kägebein, D Stucht, U Yarach, A Sciarra, R Yakupov, F Lüsebrink, P Schulze, O Speck
2016 Physics in Medicine and Biology  
Since the beginning of clinical use of MRI, many research groups have developed methods to suppress or correct motion artefacts.  ...  Subject motion in MRI is a relevant problem in the daily clinical routine as well as in scientific studies.  ...  The prevention or correction of motion-induced artefacts in brain MRI is an important objective.  ... 
doi:10.1088/0031-9155/61/5/r32 pmid:26864183 pmcid:PMC4930872 fatcat:lqh4phs4bnfmrjpddrf7sbmimm

Towards accurate and precise T 1 and extracellular volume mapping in the myocardium: a guide to current pitfalls and their solutions

Donnie Cameron, Vassilios S. Vassiliou, David M. Higgins, Peter D. Gatehouse
2017 Magnetic Resonance Materials in Physics, Biology and Medicine  
The goal of this review is to describe the most significant of these, and detail current solutions, in order to aid scientists and clinicians to maximise the utility of T 1 mapping in their clinical or  ...  Mapping of the longitudinal relaxation time (T 1 ) and extracellular volume (ECV) offers a means of identifying pathological changes in myocardial tissue, including diffuse changes that may be invisible  ...  This effect is in addition to susceptibility artefact seen in the lateral wall-another reason why clinical T 1 measurements for assessment of diffuse fibrosis are often confined to the interventricular  ... 
doi:10.1007/s10334-017-0631-2 pmid:28608328 pmcid:PMC5813078 fatcat:5n34lrvxmnfutj7q3oeafyjoje

First-pass myocardial perfusion assessment using eight-fold accelerated k-t BLAST stress DCE-MRI with rapid parametric mapping

Aleksandra Radjenovic, Sven Plein, Neil Maredia, Sebastian Kozerke, John Biglands, John Greenwood, John Ridgway
2009 Journal of Cardiovascular Magnetic Resonance  
MRI images were analysed using dedicated software (MASS © , Medis,  ...  in this setting.  ...  Acknowledgements his work was supported in part by grants from the national institute of heart, lung and blood R01HL072704 and R01HL61912, and Donald W. Reynolds Foundation grant.  ... 
doi:10.1186/1532-429x-11-s1-o34 fatcat:lmjjnjfgazgzfg3shcwjxqd7ge

Should patients with brain implants undergo MRI?

Johannes B Erhardt, Erwin Fuhrer, Oliver G Gruschke, Jochen Leupold, Matthias C Wapler, Jürgen Hennig, Thomas Stieglitz, Jan G Korvink
2018 Journal of Neural Engineering  
Permanent MRI-related neurological dysfunctions in DBS recipients have occurred in the past when manufacturer recommendations were exceeded.  ...  Therefore, we review implant safety in the MRI literature from an engineering point of view, with a focus on cochlear and DBS implants as success stories of neural implants in clinical practice.  ...  With respect to implants, susceptibility artefacts are the most relevant. Susceptibility artefacts are caused by the magnetisation of the materials in the B 0 field as described in section 2.3.2.  ... 
doi:10.1088/1741-2552/aab4e4 pmid:29513262 fatcat:q56s3g2nnvfufjs4q45pfartg4

The impact of post-processing on spinal cord diffusion tensor imaging

Siawoosh Mohammadi, Patrick Freund, Thorsten Feiweier, Armin Curt, Nikolaus Weiskopf
2013 NeuroImage  
So far, the improvements in image quality and resolution have resulted from cardiac gating and new acquisition approaches (e.g. reduced field-of-view techniques).  ...  It increased the contrast-to-noise ratio (CNR) in FA maps by about 30% and reduced intra-subject variation in fractional anisotropy (FA) maps by 18%.  ...  ., 2006) ), the "Artefact Correction in Diffusion MRI (ACID)" SPM toolbox (, and in-house software written in MATLAB (version 7.11.0; Mathworks, Natick, MA, USA).  ... 
doi:10.1016/j.neuroimage.2012.12.058 pmid:23298752 pmcid:PMC3605597 fatcat:wdg7emytnrcyrfzd3atkjaxpwi

Development of clinical simultaneous SPECT/MRI

Brian F Hutton, Michele Occhipinti, Andre Kuehne, Domokos Máthé, Noémi Kovács, Helmar Waiczies, Kjell Erlandsson, Debora Salvado, Marco Carminati, Giovanni L Montagnani, Susan C Short, Luisa Ottobrini (+9 others)
2018 British Journal of Radiology  
The limited work in this area is described with specific reference to the Integrated SPECT/MRI for Enhanced stratification in Radio-chemo Therapy (INSERT) project, which is at an advanced stage of developing  ...  Issues of SPECT/MRI compatibility are outlined and the clinical appeal of such a system is discussed, especially in the management of brain tumour treatment.  ...  For validation, transmission field distributions obtained from these simulations need to be benchmarked against experimental B 1 1 maps. 69, 70 Since the integrated SPECT module is placed outside of  ... 
doi:10.1259/bjr.20160690 pmid:28008775 fatcat:u4muewizlrb2lknqusbkv22w3a
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