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公开(公告)号：US07548063B2
公开(公告)日：2009-06-16
申请号：US11913804
申请日：2006-04-28
IPC分类号： G01V3/00
CPC分类号： G01R33/422 , G01R33/36 , G01R33/3628 , G01R33/3806
摘要： The present invention relates to a system and method magnetic resonance (MR) imaging. Furthermore the invention relates to the use of a material and to a computer program. In order to provide a technique which allows to prevent standing waves in an RF cage (3) of a MR imaging system (1) in a very cheap and simple way a MR imaging system (1) is suggested, which comprises a MR imaging apparatus (2) comprising an open magnet system (7), wherein operation of the MR imaging apparatus (2) creates a magnetic resonance field having a MR frequency, and which further comprises an RF cage (3), configured to enclose the MR imaging apparatus (2), wherein the walls (6) of the RF cage (3) are at least partly provided with a covering (5, 10), said covering (5, 10) is adapted in a way that the wavelength of the MR frequency within the covering (5, 10) is reduced.
摘要翻译： 本发明涉及一种系统和方法磁共振（MR）成像。 此外，本发明涉及材料和计算机程序的使用。 为了提供允许以非常便宜和简单的方式在MR成像系统（1）的RF笼（3）中防止驻波的技术，建议MR成像系统（1），其包括MR成像装置 （2），其包括开放磁体系统（7），其中所述MR成像设备（2）的操作产生具有MR频率的磁共振场，并且还包括RF笼（3），其被配置为包围所述MR成像设备 （2），其中所述RF笼（3）的壁（6）至少部分地设置有覆盖物（5,10），所述覆盖物（5,10）以使得MR频率的波长 在覆盖物（5,10）内减少。
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公开(公告)号：US20080197847A1
公开(公告)日：2008-08-21
申请号：US11913804
申请日：2006-04-28
IPC分类号： G01R33/36
CPC分类号： G01R33/422 , G01R33/36 , G01R33/3628 , G01R33/3806
摘要： The present invention relates to a system and method magnetic resonance (MR) imaging. Furthermore the invention relates to the use of a material and to a computer program. In order to provide a technique which allows to prevent standing waves in an RF cage (3) of a MR imaging system (1) in a very cheap and simple way a MR imaging system (1) is suggested, which comprises a MR imaging apparatus (2) comprising an open magnet system (7), wherein operation of the MR imaging apparatus (2) creates a magnetic resonance field having a MR frequency, and which further comprises an RF cage (3), configured to enclose the MR imaging apparatus (2), wherein the walls (6) of the RF cage (3) are at least partly provided with a covering (5, 10), said covering (5, 10) is adapted in a way that the wavelength of the MR frequency within the covering (5, 10) is reduced.
摘要翻译： 本发明涉及一种系统和方法磁共振（MR）成像。 此外，本发明涉及材料和计算机程序的使用。 为了提供允许以非常便宜和简单的方式在MR成像系统（1）的RF笼（3）中防止驻波的技术，建议MR成像系统（1），其包括MR成像装置 （2），其包括开放磁体系统（7），其中所述MR成像设备（2）的操作产生具有MR频率的磁共振场，并且还包括RF笼（3），其被配置为包围所述MR成像设备 （2），其中所述RF笼（3）的壁（6）至少部分地设置有覆盖物（5,10），所述覆盖物（5,10）以使得MR频率的波长 在覆盖物（5,10）内减少。
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公开(公告)号：US20080262340A1
公开(公告)日：2008-10-23
申请号：US11569069
申请日：2005-05-12
IPC分类号： A61B5/055 , G01R33/563
CPC分类号： G01R33/56375
摘要： The invention relates to a MRI system and to a method for producing an image with such an system. In order to provide a MR imaging technique with a high efficient MR signal acquisition, which provides a high level of comfort to a patient, a MRI system and method are suggested, where image data from an object are acquired while the object is moving with variable speed relative to the MRI system, and where the image data are combined and an image of the object is reconstructed.
摘要翻译： 本发明涉及一种MRI系统和一种用这种系统生产图像的方法。 为了提供具有高效MR信号采集的MR成像技术，其为患者提供高水平的舒适性，建议了MRI系统和方法，其中在物体运动时获取来自对象的图像数据， 相对于MRI系统的速度，并且其中图像数据被组合并且重建对象的图像。
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公开(公告)号：US09689941B2
公开(公告)日：2017-06-27
申请号：US13993689
申请日：2011-12-05
IPC分类号： G01R33/3873 , G01R33/24 , G01R33/565 , G01R33/54 , G01R33/34
CPC分类号： G01R33/3873 , G01R33/246 , G01R33/34 , G01R33/34076 , G01R33/543 , G01R33/5659
摘要： Coil elements (18) generate a B1 excitation field in an examination region (14), which B1 excitation field is distorted by patient loading (e.g., wavelength effects). Passive shimming elements (22, 24) are disposed between the coil elements and the subject in order to improve the B1 field uniformity. In one embodiment, passive shimming elements include one or more dielectric rods (55) disposed below the subject which generate no substantial MR proton signal and which have a permittivity of at least 100 and preferably greater than 500. In another embodiment, tubes (24) adjacent each coil element are supplied with a dielectric liquid, a thickness of the dielectric liquid between the coil element and the subject adjusting a phase of the B1 field generated by the coil element. Active B1 shimming may be combined with passive shimming elements (22, 24) to effect an improved RF field homogeneity result.
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公开(公告)号：US20130278262A1
公开(公告)日：2013-10-24
申请号：US13993689
申请日：2011-12-05
IPC分类号： G01R33/3873
CPC分类号： G01R33/3873 , G01R33/246 , G01R33/34 , G01R33/34076 , G01R33/543 , G01R33/5659
摘要： Coil elements (18) generate a B1 excitation field in an examination region (14), which B1 excitation field is distorted by patient loading (e.g., wavelength effects). Passive shimming elements (22, 24) are disposed between the coil elements and the subject in order to improve the B1 field uniformity. In one embodiment, passive shimming elements include one or more dielectric rods (55) disposed below the subject which generate no substantial MR proton signal and which have a permittivity of at least 100 and preferably greater than 500. In another embodiment, tubes (24) adjacent each coil element are supplied with a dielectric liquid, a thickness of the dielectric liquid between the coil element and the subject adjusting a phase of the B1 field generated by the coil element. Active B1 shimming may be combined with passive shimming elements (22, 24) to effect an improved RF field homogeneity result.
摘要翻译： 线圈元件（18）在检查区域（14）中产生B1激励场，其中B1激励场由患者负载变形（例如，波长效应）。 被动调光元件（22,24）设置在线圈元件和被摄体之间，以提高B1场均匀性。 在一个实施例中，被动调光元件包括设置在对象下方的一个或多个介电棒（55），其不产生实质的MR质子信号，并且具有至少100，优选大于500的介电常数。在另一实施例中，管（24） 相邻的每个线圈元件被提供有电介质液体，线圈元件和对象之间的电介质液体的厚度调节由线圈元件产生的B1场的相位。 有源B1匀场可以与被动调光元件（22,24）组合以实现改进的RF场均匀性结果。
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公开(公告)号：US07208949B2
公开(公告)日：2007-04-24
申请号：US10542828
申请日：2003-12-15
申请人： Miha Fuderer
发明人： Miha Fuderer
IPC分类号： G01V3/00
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.
摘要翻译： 提出了用于形成物体的图像的磁共振成像方法，其中施加具有位置相关磁场图案的固定磁场和临时磁场，通过至少一个接收器天线获取磁共振信号，旋转在 在对象的一部分中，在施加位置相关的场图案（G 1，G 2，...）期间获取MR信号，并且从采样的磁共振信号导出磁共振图像。 场图案基本上是非线性的，总场图案的数量N大于3，并且至少N-1场图案在场强中是独立可控的。 以次采样的方式获取磁共振信号。
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公开(公告)号：US06897653B2
公开(公告)日：2005-05-24
申请号：US09992699
申请日：2001-11-14
IPC分类号： G01R33/36 , A61B5/055 , G01R33/565 , G01V3/00
CPC分类号： G01R33/56518
摘要： In a magnetic resonance imaging method flow quantities and diffusion quantities are measured in the presence of temporary magnetic gradient fields (gradient pulses). Signal amplitudes of the magnetic resonance signals and/or flow and diffusion quantities calculated from the magnetic resonance signals are corrected for non-linearities in the magnetic gradient fields.
摘要翻译： 在磁共振成像方法中，在临时磁梯度场（梯度脉冲）的存在下测量流量和扩散量。 根据磁共振信号计算的磁共振信号和/或流量和扩散量的信号幅度被校正为磁梯度场中的非线性。
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公开(公告)号：US6049623A
公开(公告)日：2000-04-11
申请号：US770389
申请日：1996-12-20
申请人： Miha Fuderer , Til Aach , Dietmar W. Kunz
发明人： Miha Fuderer , Til Aach , Dietmar W. Kunz
CPC分类号： G06T5/20 , G01R33/5608
摘要： An image is processed taking into account the direction of a predominant structure of the image. Said predominant direction is derived from image information in the image. In particular, the covariance matrix having matrix elements depending on products of differences between pixel-values in separate directions is calculated. The eigenvectors of the covariance matrix correspond with the predominant direction of the image structure and the eigenvalues of the covariance matrix represent the strength of the structure in the image. The covariance matrix is computed locally, i.e. for separate regions in the images so as to take variations of the direction of predominant structures into account.
摘要翻译： 考虑到图像的主要结构的方向来处理图像。 所述主要方向来源于图像中的图像信息。 特别地，计算具有取决于分离方向上的像素值之间的差的乘积的矩阵元素的协方差矩阵。 协方差矩阵的特征向量与图像结构的主要方向对应，协方差矩阵的特征值表示图像中结构的强度。 局部计算协方差矩阵，即为图像中的单独区域计算，以便考虑主要结构方向的变化。
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9.发明授权Grase MRI with read gradient polarity correction and T.sub.2 measurement 失效具有读取梯度极性校正和T2测量的Grase MRI
公开(公告)号：US5581181A
公开(公告)日：1996-12-03
申请号：US362620
申请日：1994-12-22
申请人： Miha Fuderer
发明人： Miha Fuderer
IPC分类号： G01R33/54 , A61B5/055 , G01R33/50 , G01R33/56 , G01R33/561 , G01R33/563 , G01R33/48
CPC分类号： G01R33/56554 , G01R33/50 , G01R33/5615
摘要： In a GRASE magnetic resonance method, most profiles in k-space with a certain k.sub.y value are measured with different magnetic field read gradient polarity and at different time intervals from the excitation RF-pulse. The two resulting sets of measurements, with positive and negative read gradient polarity, respectively, are used to correct read gradient polarity dependent phase errors, in order to obtain reconstructed images in which the effects of these phase errors are greatly reduced. In an improved version the measurements are used to reconstruct images with a predictable T.sub.2 weighting.
摘要翻译： 在GRASE磁共振方法中，具有一定ky值的k空间中的大部分轮廓是用不同的磁场读取梯度极性和与激励RF脉冲不同的时间间隔来测量的。 分别使用正和负读取梯度极性的两组测量结果来校正读取梯度极性相关的相位误差，以便获得这些相位误差的影响大大降低的重构图像。 在改进的版本中，测量用于以可预测的T2加权重建图像。
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10.发明授权Magnetic resonance imaging method and device for reducing image errors in a magnetic resonance image 失效用于降低磁共振图像中的图像误差的磁共振成像方法和装置
公开(公告)号：US5262725A
公开(公告)日：1993-11-16
申请号：US811560
申请日：1991-12-20
申请人： Johannes J. M. Cuppen , Miha Fuderer , Antoon F. Mehlkope , Michael J. Duijvestijn , Gerrit H. Van Yperen
发明人： Johannes J. M. Cuppen , Miha Fuderer , Antoon F. Mehlkope , Michael J. Duijvestijn , Gerrit H. Van Yperen
IPC分类号： A61B5/055 , G01R33/48 , G01R33/565 , G01R33/567 , G06Q50/00 , G01R33/20
CPC分类号： G01R33/565 , G01R33/56509
摘要： In magnetic resonance imaging various error sources lead to deterioration of the image quality. One class of errors is formed by errors which vary only slowly over the time required to sample a data line but vary substantially over the time required to acquire data for the complete magnetic resonance image. These error sources are, for example external magnetic fields, motion due to respiration, drift in amplifiers or drift phenomena in permanent magnets due to temperature influences. It is proposed to utilize mutually intersecting data lines in the Fourier domain so as to estimate these error sources and to use these estimates to correct the data sets obtained before execution of image reconstruction.
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