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公开(公告)号：EP1307757B1
公开(公告)日：2012-09-12
申请号：EP01960497.4
申请日：2001-07-13
发明人： FUDERER, Miha , VAN DEN BRINK, Johan, S. , JURRISSEN, Michel, P., J. , VAN MUISWINKEL, Arianne, M., C. , KATSCHER, Ulrich
IPC分类号： G01R33/561 , G01R33/3415
CPC分类号： G01R33/5611 , G01R33/4835
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公开(公告)号：EP2255214A1
公开(公告)日：2010-12-01
申请号：EP09720031.5
申请日：2009-03-06
IPC分类号： G01R33/561 , G01R33/3415
CPC分类号： G01R33/022 , G01R33/3415 , G01R33/3664 , G01R33/543 , G01R33/5611 , G01R33/5659
摘要： The invention relates to a method of selecting a set of coil elements from a multitude of physical coil elements comprised in a coil array for performing a magnetic resonance imaging scan of a region of interest.
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公开(公告)号：EP2044454A1
公开(公告)日：2009-04-08
申请号：EP07789868.2
申请日：2007-07-03
发明人： FUDERER, Miha
IPC分类号： G01R33/3415 , G01R33/565
CPC分类号： G01R33/3415 , G01R33/56509
摘要： A magnetic resonance imaging system (1), comprising a plurality of receiving units (4.1-4.4) for receiving magnetic resonance signals from an object (2), and an image reconstruction device (8), said image reconstruction device being adapted to receive magnetic resonance signals of said object (2) from said plurality of receiving units (4.1-4.4) and to perform image reconstruction by combining magnetic resonance signals received by said plurality of receiving units using an image reconstruction algorithm (11), characterised in that said image reconstruction device (8) comprises means (12a) for combining magnetic resonance signal contributions from respective receiving units (4.1-4.4) in such a way that a combined sensitivity of the plurality of receiving units (4.1-4.4) to a predetermined spatial region of the object (2) is reduced.
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公开(公告)号：EP1444529B1
公开(公告)日：2008-08-20
申请号：EP02777646.7
申请日：2002-10-24
发明人： FUDERER, Miha
IPC分类号： G01R33/561
CPC分类号： G01R33/561 , G01R33/4824 , G01R33/5611 , G01R33/56545 , Y10T436/24
摘要： A novel magnetic resonance imaging method is described, wherein the object to be imaged is segmented into a region of slow variation and into a region of fast variation which defines a restrictive dynamic FOV. The object in the overall FOV is sampled in k-space with a reduction factor. The k-space sampling positions in the region of fast variation are transformed by Fourier Transformation to the spatial domain and are transformed additionally to the temporal-frequency domain. Further the positions in the temporal-frequency domain derived from the sub-sampled positions in k-space are unfolded on the basis of the spatial coil sensitivity profiles of the set of receiving coils, whereas the parts of the temporal-frequency domain related to the region of slow variation are set to zero, and the resulting data in the temporal-frequency domain is Fourier transformed to the temporal domain.
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公开(公告)号：EP1733245A1
公开(公告)日：2006-12-20
申请号：EP05718539.9
申请日：2005-03-21
IPC分类号： G01R33/422
CPC分类号： G01R33/34076 , G01R33/246
摘要： The invention relates to a system for magnetic resonance imaging (MRI). Such systems face an additional contribution to the inhomogeneity of the radio frequency (RF) field when high magnetic fields are applied. The invention tries to improve the homogeneity of the RF field for high field strengths, particularly for field strengths at or above 3 tesla. To improve the homogeneity an electrically conducting material (4) is positioned within the cavity (2) of the system. The material has a conductivity and a thickness which ensure that the total radial conductance in an xy-plane perpendicular to the symmetry axis of the cavity becomes isotropic.
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36.发明公开DETERMINATION OF SPATIAL SENSITIVITY PROFILES OF RF COILS IN MAGNETIC RESONANCE IMAGING 审中-公开确定磁共振成像RF线圈的空间灵敏度的轮廓
公开(公告)号：EP1660899A1
公开(公告)日：2006-05-31
申请号：EP04744764.4
申请日：2004-08-09
发明人： FUDERER, Miha , KLEIHORST, Robert
IPC分类号： G01R33/32 , G01R33/561
CPC分类号： G01R33/246 , G01R33/3415 , G01R33/5611 , G01R33/5659
摘要： The invention relates to a method for determination of spatial sensitivity profiles of RF transmit and/or receive coils (7, 8, 9) in an examination volume (17) of a magnetic resonance (MR) imaging device (1). In accordance with the method of the invention, nuclear magnetization is excited within the examination volume (17) by a sequence of RF pulses and switched magnetic field gradients, wherein the sequence comprises RF pulses with at least two different excitation flip angles. MR signals are acquired and processed so as to form at least two MR images, each corresponding to one of these flip angles. The spatial sensitivity profiles are then computed in the positions of the pixels or voxels of the MR images based upon the dependence of the pixel or voxel values on the respective flip angles. Alternatively, a plurality of instances of a sequence of RF pulses and switched magnetic field gradients is applied and MR signals are acquired, wherein a different combination of transmit and receive coils (7, 8, 9) is used for each instance of the sequence. The spatial sensitivity profiles are then computed in the positions of the pixels or voxels of the MR images formed from the acquired MR signals by taking the logarithm of the pixel or voxel values and by solving a linear system of equations for each pixel or voxel.
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公开(公告)号：EP1642149A1
公开(公告)日：2006-04-05
申请号：EP04731084.2
申请日：2004-05-04
发明人： FUDERER, Miha
IPC分类号： G01R33/561
CPC分类号： G01R33/5611 , G01R33/56308
摘要： A novel magnetic resonance imaging method is described for forming a sequence of images from a plurality of signals acquired by at least one receiver antenna. Each receiver antenna has a spatial sensitivity profile. An activity map is calculated as a standard deviation over a series of images acquired by a reference scan. Thereupon, the object is sampled in an actual scan in an interleaved manner in k-space with a reduction factor. The resulting data is Fourier transformed to the spatial domain to form a sequence of folded preliminary images, and the fold-over artefacts or the ambiguity in the preliminary images resulting from the undersampled data in k-space is resolved in forming the actual images on the basis of the activity map.
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公开(公告)号：EP1588183A1
公开(公告)日：2005-10-26
申请号：EP03796223.0
申请日：2003-12-15
发明人： FUDERER, Miha
IPC分类号： G01R33/565 , G01R33/561
CPC分类号： G01R33/56518 , G01R33/5611 , G01R33/56563
摘要： A magnetic resonance imaging method is presented for forming an image of an object, wherein a stationary magnetic field and temporary magnetic fields having a position dependent field pattern are applied, magnetic resonance signals are acquired by at least one receiver antenna, spins are excitated in a part of the object, MR signals are acquired during application of the position-dependent field patterns (G1, G2,...) and a magnetic resonance image is derived from the sampled magnetic resonance signals. The field patterns are substantially non-linear, the number N of total field patterns is larger than 3, and at least N -1 field patterns are independently controllable in field strength. The magnetic resonance signals are acquired in a sub-sampling fashion.
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