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Experimental Data and Geometric Analysis Repository—EDGAR

Kedar Aras, Wilson Good, Jess Tate, Brett Burton, Dana Brooks, Jaume Coll-Font, Olaf Doessel, Walther Schulze, Danila Potyagaylo, Linwei Wang, Peter van Dam, Rob MacLeod
2015 Journal of Electrocardiology  
Methods: The EDGAR system is composed of two interrelated components: 1) a metadata model, which includes a set of descriptive parameters and information, time signals from both the cardiac source and  ...  body-surface, and extensive geometric information, including images, geometric models, and measure locations used during the data acquisition/generation; and 2) a web interface.  ...  The first Workshop on ECG Imaging in 2015 was financially supported by the German Research Foundation under the grant DO 637/13-1.  ... 
doi:10.1016/j.jelectrocard.2015.08.008 pmid:26320369 pmcid:PMC4624576 fatcat:qquspecxwna37cvq6vvaekory4

Inversion Reconstruction of Signals Measured by the NMR Techniques

Pavel Fiala, Eva Kroutilova, M. Steinbauer, Michal Hadinec, Karel Bartusek
2007 PIERS Online  
The paper describes the magnetic resonance imaging method applicable mainly in MRI and MRS in vivo studies. There is discussed and solved the effect of changes of magnetic fields in MR tomography.  ...  This article deals with the reverse reconstruction results obtained from the numerical simulation of MR signals by various techniques, which will be usable for the experimental results verification.  ...  approximation (EBA) and the combination of the EBA and the contrast source inversion (CSI) method.  ... 
doi:10.2529/piers070220104727 fatcat:4tb445eozvc25jxwz5bs3ukxga

Nonlinear electrocardiographic imaging using polynomial approximation networks

Abhejit Rajagopal, Vincent Radzicki, Hua Lee, Shivkumar Chandrasekaran
2018 APL Bioengineering  
voltage potentials of the heart and torso, the presented technique re-casts this problem as a task in function approximation and provides a direct parameterization of the inverse operator using a polynomial  ...  That is, the outlined nonlinear inversion technique is a generalization of contemporary reconstruction techniques which allows geometrical and material parameterizations of the forward-model to be optimized  ...  Birmingham, UK) for their invaluable advice and insights into the applicability of ECGi in electrophysiology.  ... 
doi:10.1063/1.5038046 pmid:31069323 pmcid:PMC6481726 fatcat:ofhylvf27nflfjy75c6kpey2qa

Supercomputer technologies in tomographic imaging applications

2016 Supercomputing Frontiers and Innovations  
One of the main challenges in ultrasound tomographic imaging is the development of efficient algorithms for solving inverse problems of wave tomography, which are nonlinear three-dimensional coefficient  ...  Early breast cancer diagnosis is one of the most pressing issues in modern healthcare. Ultrasound tomography devices are being developed in the USA, Germany and Russia to address this problem.  ...  Model calculations of inverse problems of wave tomography in integral formulation To assess efficiency of the algorithms proposed in section 2.2, the model problems of reconstructing the structure of the  ... 
doi:10.14529/jsfi160103 fatcat:m6o4wejz6vebpomou5m7mw6you

The Consortium for Electrocardiographic Imaging

Jaume Coll-Font, Jwala Dhamala, Danila Potyagaylo, Walther Hw Schulze, Jess D Tate, Maria S Guillem, Peter van Dam, Olaf Dossel, Dana H Brooks, Rob S Macleod
2017 Computing in cardiology  
To address these limitations, we created the Consortium for Electrocardiographic Imaging (CEI), with the objective of facilitating collaboration across the research community in ECGI and creating standards  ...  in ECGI.  ...  These initiatives will form a continuous evaluation of the field, which is expected to yield collaborative and consensus publications reporting on the state-of-the-art of ECGI.  ... 
pmid:28451592 pmcid:PMC5404701 fatcat:7yowlj2csfhnhpfliixkq3uz5i

Stochastic Inverse Consistency in Medical Image Registration [chapter]

Sai Kit Yeung, Pengcheng Shi
2005 Lecture Notes in Computer Science  
An essential goal in medical image registration is, the forward and reverse mapping matrices should be inverse to each other, i.e., inverse consistency.  ...  Conventional approaches enforce consistency in deterministic fashions, through incorporation of sub-objective cost function to impose source-destination symmetric property during the registration process  ...  Inverse Consistency in Medical Image Registration Discrete Nature of the Information Sources Due to the discrete nature of data, either the point representation or the digital medical image of the biological  ... 
doi:10.1007/11566489_24 fatcat:kkxm3sgkwvetdlyc2df37izcb4

Influence of different sources of noise on epileptic spike EEG source localization

Yazdan Shirvany, Xinyuan Chen, Prathamesh Sharad Dhanpalwar, Mahdieh Mir Hashemi, Fredrik Edelvik, Mikael Persson, John B. Weaver, Robert C. Molthen
2013 Medical Imaging 2013: Biomedical Applications in Molecular, Structural, and Functional Imaging  
To understand the influence of EEG signal noise, tissue conductivity noise and electrode misplacements on the EEG source localization, different level of noises are added to EEG signals, tissue conductivities  ...  For accurate source localization, understanding the affects of these errors on the source localization is very crucial. Six finite element head models are selected for a head-model complexity study.  ...  The inverse problem in EEG source localization uses the scalp EEG signal to estimate the corresponding current source inside the brain and it is an underdetermined problem and no unique solution can usually  ... 
doi:10.1117/12.2007118 fatcat:7kueppokzrblhmza73vmb762s4

Computer Spatially Oriented Reconstruction of A 3D Heart Shape Based on Its Tomographic Imaging

Natalya Natalinova, Diana Avdeeva, Veniamin Kazakov, Vladimir Baranov, Olga Galtseva,, Denis Ivashkov, A.V. Yurchenko, V.I. Syryamkin
2016 MATEC Web of Conferences  
The problem is solved with the help of computer tomography method by preparing a series of images of the patient heart.  ...  It is concluded that the character of the obtained three-dimensional model of the patient heart is determined by the quality of the input data, the resolution of the tomograph, the tomographic slice thickness  ...  Acknowledgment The research was financially supported by the Federal Targeted Programme "Research and Development in Priority Fields of S&T Complex of Russia in 2014-2020", the Agreement No. 14.578.21.0032  ... 
doi:10.1051/matecconf/20167901005 fatcat:ankismj5cjbxvnvvtd5yoozxfu

Noninvasive detection of epicardial and endocardial activity of the heart

T. F. Oostendorp, P. F. H. M. van Dessel, R. Coronel, C. Belterman, A. C. Linnenbank, I. H. van Schie, A. van Oosterom, P. Oosterhoff, P. M. van Dam, J. M. T. de Bakker
2011 Netherlands Heart Journal  
Determining electrical activation of the heart in a noninvasive way is one of the challenges in cardiac electrophysiology.  ...  Information obtained in this way might be helpful for the treatment of arrhythmias, to assess the effect of drugs on conduction in the heart and to assess electrical stability of the heart.  ...  The inverse problem involves determination of the electrical activity of the heart from recorded body surface signals and the geometry of heart and thorax.  ... 
doi:10.1007/s12471-011-0206-1 pmid:22006012 pmcid:PMC3203979 fatcat:kwhzywukqjb5pkrrdxsg74zfha

Advances in Blind Source Separation

Andrzej Cichocki, Frank Ehlers
2007 EURASIP Journal on Advances in Signal Processing  
In the third paper, Fabian J. Theis et al. consider sparse component analysis problem for an overcomplete model using Hough transform.  ...  In the second paper Scott Douglas developed new fixedpoint algorithms for the blind separation of complex-valued mixtures of non-circularly-symmetric, and non-Gaussian independent source signals.  ...  Starting from the inverse filter criterion introduced by Tugnait and Li, they propose to tackle the problem in the context of the blind signal extraction methods for ICA.  ... 
doi:10.1155/2007/57314 fatcat:jha57qhoxbhlphi54epmf7qp4i

Solving Inaccuracies in Anatomical Models for Electrocardiographic Inverse Problem Resolution by Maximizing Reconstruction Quality

Miguel Rodrigo, Andreu M. Climent, Alejandro Liberos, Ismael Hernandez-Romero, Angel Arenal, Javier Bermejo, Francisco Fernandez-Aviles, Felipe Atienza, Maria S. Guillem
2018 IEEE Transactions on Medical Imaging  
Body surface electrical signals from 31 realistic mathematical models and four AF patients were used to estimate the optimal position of the atria inside the torso.  ...  For the case of independent angular deviations, the error in location by using the L-curve was 5.8±7.1º in mathematical models and 12.4º±13.2º in patients.  ...  Anatomical models and inverse problem resolution Solution of the inverse problem of electrocardiography generally involves the recording of MRI or CT images for obtaining accurate anatomical models of  ... 
doi:10.1109/tmi.2017.2707413 pmid:28541896 fatcat:hslbjxjwg5abdiryj2ytcqoi3m

Advances in neuro diagnostics based on microwave technology, transcranial magnetic stimulation and EEG source localization

Mikael Persson, Tomas Mckelvey, Andreas Fhager, Yazdan Shirvany, Artur Chodorowski, Qaiser Mahmood, Fredrik Edelevik, Magnus Thordstein, Anders Hedstrom, Mikael Elam
2011 2011 XXXth URSI General Assembly and Scientific Symposium  
Methods for solving the inverse problem in EEG-based source localization are based on solutions of the corresponding forward problem, i.e. simulation of the potentials on the scalp for a given source.  ...  To find the brain sources, which are usually modeled as current dipoles, that are responsible for the measured potentials at the EEG electrodes on the scalp is an inverse problem.  ... 
doi:10.1109/ursigass.2011.6123736 fatcat:f7stnmtukbfdzdubswbyzowuwi

EEG/MEG Source Imaging: Methods, Challenges, and Open Issues

Katrina Wendel, Outi Väisänen, Jaakko Malmivuo, Nevzat G. Gencer, Bart Vanrumste, Piotr Durka, Ratko Magjarević, Selma Supek, Mihail Lucian Pascu, Hugues Fontenelle, Rolando Grave de Peralta Menendez
2009 Computational Intelligence and Neuroscience  
We present the four key areas of research—preprocessing, the volume conductor, the forward problem, and the inverse problem—that affect the performance of EEG and MEG source imaging.  ...  More than providing definitive answers we aim to identify important open issues in the quest of source localization.  ...  Neither the COST Office nor any person acting on its behalf is responsible for the use, which might be made of the information contained in this publication.  ... 
doi:10.1155/2009/656092 pmid:19639045 pmcid:PMC2715569 fatcat:dev75naixzbn3nnza62p75svdm

A Fast and Efficient Frequency-Domain Method for Convolutive Blind Source Separation

Peng Xie, Steven L. Grant
2008 2008 IEEE Region 5 Conference  
In this paper, the problem of blind separation of a convolutive mixture of audio signals is considered.  ...  The amplitude problem is addressed by utilizing the elements in the inverse of the separation matrix.  ...  ACKNOWLEDGMENT The authors would like to thank Aapo Hyvärinen and Erkki Oja, Helsinki University of Technology, Finland, for making their valuable FastICA code available.  ... 
doi:10.1109/tpsd.2008.4562739 fatcat:d4zhpbcv2fgzbfgeqmffh5swwu

Body Surface Potential Mapping: Contemporary Applications and Future Perspectives

Jake Bergquist, Lindsay Rupp, Brian Zenger, James Brundage, Anna Busatto, Rob S. MacLeod
2021 Hearts  
We assess the state of the art of BSPM implementations and explore modern applications of advanced modeling and statistical analysis of BSPM data.  ...  BSPM provides comprehensive acquisition of bioelectric signals across the entire thorax, allowing for more complex and extensive analysis than the standard electrocardiogram (ECG).  ...  Recorded body surface potentials (left) are combined with a geometric model and a source model. The geometric model is made up of the relative positions of the cardiac geometry and torso geometry.  ... 
doi:10.3390/hearts2040040 fatcat:sgzzoo76b5f3fgewfklu6wzdei
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