公开(公告)号：US10126397B2

公开(公告)日：2018-11-13

申请号：US14707598

申请日：2015-05-08

申请人： Stephen Cauley ,  Berkin Bilgic ,  Kawin Setsompop ,  Lawrence Wald

发明人： Stephen Cauley ,  Berkin Bilgic ,  Kawin Setsompop ,  Lawrence Wald

IPC分类号： G01R33/56 ,  G01R33/561 ,  G01R33/385 ,  G01R33/567

摘要： Systems and methods for reconstructing images using a hierarchically semiseparable (“HSS”) solver to compactly represent the inverse encoding matrix used in the reconstruction are provided. The reconstruction method includes solving for the actual inverse of the encoding matrix using a direct (i.e., non-iterative) HSS solver. This approach is contrary to conventional reconstruction methods that repetitively evaluate forward models (e.g., compressed sensing or parallel imaging forward models).

公开(公告)号：US09594141B2

公开(公告)日：2017-03-14

申请号：US13633908

申请日：2012-10-03

申请人： Daniel Weller ,  Leo Grady ,  Lawrence Wald ,  Vivek K Goyal

发明人： Daniel Weller ,  Leo Grady ,  Lawrence Wald ,  Vivek K Goyal

IPC分类号： G01R33/341 ,  G01R33/58 ,  G01R33/561

CPC分类号： G01R33/5611

摘要： An MR imaging system uses multiple RF coils for acquiring corresponding multiple image data sets of a slice or volume of patient anatomy. An image data processor comprises at least one processing device conditioned for, deriving a first set of weights for weighted combination of k-space data of the multiple image data sets for generating a calibration data set comprising a subset of k-space data of composite image data representing the multiple image data sets. The image data processor uses the calibration data set in generating a first MR image data set, deriving the parameters of a probability distribution in response to the first set of weights and the first MR image data set and deriving a second set of weights and second MR image data set together using the probability distribution.

摘要翻译： MR成像系统使用多个RF线圈来获取患者解剖结构的切片或体积的相应的多个图像数据集。 图像数据处理器包括至少一个处理装置，该处理装置被调节为：为多个图像数据集的k空间数据的加权组合推导第一组加权，以产生包括合成图像的k空间数据子集的校准数据集 表示多个图像数据集的数据。 图像数据处理器使用校准数据集来生成第一MR图像数据集，响应于第一组权重和第一MR图像数据集导出概率分布的参数并导出第二组权重和第二MR 使用概率分布将图像数据集合在一起。

公开(公告)号：US20130207652A1

公开(公告)日：2013-08-15

申请号：US13633908

申请日：2012-10-03

申请人： Daniel Weller ,  Leo Grady ,  Lawrence Wald ,  Vivek K. Goyal

发明人： Daniel Weller ,  Leo Grady ,  Lawrence Wald ,  Vivek K. Goyal

IPC分类号： G01R33/341 ,  G01R33/58

CPC分类号： G01R33/5611

摘要： An MR imaging system uses multiple RF coils for acquiring corresponding multiple image data sets of a slice or volume of patient anatomy. An image data processor comprises at least one processing device conditioned for, deriving a first set of weights for weighted combination of k-space data of the multiple image data sets for generating a calibration data set comprising a subset of k-space data of composite image data representing the multiple image data sets. The image data processor uses the calibration data set in generating a first MR image data set, deriving the parameters of a probability distribution in response to the first set of weights and the first MR image data set and deriving a second set of weights and second MR image data set together using the probability distribution.

摘要翻译： MR成像系统使用多个RF线圈来获取患者解剖结构的切片或体积的相应的多个图像数据集。 图像数据处理器包括至少一个处理装置，该处理装置被调节为：为多个图像数据集的k空间数据的加权组合推导第一组加权，以产生包括合成图像的k空间数据子集的校准数据集 表示多个图像数据集的数据。 图像数据处理器使用校准数据集来生成第一MR图像数据集，响应于第一组权重和第一MR图像数据集导出概率分布的参数并导出第二组权重和第二MR 使用概率分布将图像数据集合在一起。

公开(公告)号：US20130015854A1

公开(公告)日：2013-01-17

申请号：US13181868

申请日：2011-07-13

申请人： Elfar Adalsteinsson ,  Hans-Peter Fautz ,  Kawin Setsompop ,  Lawrence Wald

发明人： Elfar Adalsteinsson ,  Hans-Peter Fautz ,  Kawin Setsompop ,  Lawrence Wald

IPC分类号： G01R33/44

CPC分类号： G01R33/56563 ,  G01R33/446 ,  G01R33/5607 ,  G01R33/5612 ,  G01R33/5614

摘要： In a magnetic resonance apparatus and operating method therefor, and in a processor that is programmed to design RF pulses for operating such a magnetic resonance apparatus, the RF pulses are designed to mitigate off-resonance effects caused by inhomogeneity of the basic (B0) magnetic field in the magnetic resonance apparatus. The RF pulses of a parallel transmit array are designed with different spatial phase distributions, that deviate from a constant phase from pulse-to-pulse, with the absolute value of the difference between respective spatial phase distributions of any two successively radiated RF pulses corresponding to the off-resonance that is caused by B0-inhomogeneity during the time between the radiation of the successive pulses. Additionally, or separately, currents supplied to the shim coils can be taken into account in the design of the RF pulses as an additional degree of freedom, with the shimming of the basic magnetic field produced by the shim currents deviating from shim currents designed to ideally produce a homogenous B0 field.

摘要翻译： 在一种磁共振装置及其操作方法中，并且在被编程为设计用于操作这种磁共振装置的RF脉冲的处理器中，RF脉冲被设计成减轻由基本（B0）磁性的不均匀性引起的非共振效应 磁场。 平行发射阵列的RF脉冲被设计为具有不同的空间相位分布，其偏离了脉冲到脉冲的恒定相位，对应于任何两个相继辐射的RF脉冲的相应空间相位分布之间的差的绝对值 在连续脉冲的辐射期间由B0不均匀性引起的非共振。 此外，或者单独地，作为附加自由度，在RF脉冲的设计中可以考虑提供给垫片线圈的电流，同时由偏置电流产生的基本磁场的匀场偏离设计成理想的电流 产生均匀的B0场。

公开(公告)号：US10295624B2

公开(公告)日：2019-05-21

申请号：US13918461

申请日：2013-06-14

申请人： Elfar Adalsteinsson ,  Luca Daniel ,  Bastien Guerin ,  Zohaib Mahmood ,  Markus Vester ,  Lawrence Wald

发明人： Elfar Adalsteinsson ,  Luca Daniel ,  Bastien Guerin ,  Zohaib Mahmood ,  Markus Vester ,  Lawrence Wald

IPC分类号： G01V3/00 ,  G01R33/36 ,  G01R33/561

摘要： A method of determining a decoupling matrix of a decoupling system for an array of coils of a parallel transmission magnetic resonance imaging (MRI) system includes obtaining impedance matrix data for the array of coils without the decoupling system, determining, based on the impedance matrix data for the array of coils, an objective function representative of deviation from a decoupled operating condition for the array of coils in which the array of coils are decoupled via the decoupling system, and defining, with a processor, a decoupling matrix representative of a set of impedances of the decoupling system with an iterative procedure that optimizes elements of the decoupling matrix to minimize the objective function and reach the decoupled operating condition.

公开(公告)号：US09588207B2

公开(公告)日：2017-03-07

申请号：US13615785

申请日：2012-09-14

申请人： Daniel Weller ,  Leo Grady ,  Lawrence Wald ,  Vivek K Goyal

发明人： Daniel Weller ,  Leo Grady ,  Lawrence Wald ,  Vivek K Goyal

IPC分类号： G01R33/341 ,  G01R33/58 ,  G01R33/561

CPC分类号： G01R33/5611

摘要： A system for parallel image processing in MR imaging comprises multiple MR imaging RF coils for individually receiving MR imaging data representing a slice of patient anatomy. An MR imaging system uses the multiple RF coils for acquiring corresponding multiple image data sets of the slice. An image data processor comprises at least one processing device conditioned for, deriving a first set of weights for generating a calibration data set comprising a subset of k-space data of composite image data representing the multiple image data sets. The at least one processing device uses the calibration data set in generating a first MR image data set, deriving a second set of weights using the calibration data set and the generated first MR image data set and uses the second set of weights in generating a second MR image data set representing a single image having a reduced set of data components relative to the first composite MR image data set.

摘要翻译： 用于MR成像中的并行图像处理的系统包括多个MR成像RF线圈，用于单独接收表示患者解剖结构的切片的MR成像数据。 MR成像系统使用多个RF线圈来获取切片的相应多个图像数据集。 图像数据处理器包括至少一个处理装置，该处理装置被调节为：产生第一组权重，用于生成包括表示多个图像数据集的合成图像数据的k空间数据的子集的校准数据集。 所述至少一个处理装置在生成第一MR图像数据集时使用校准数据集，使用校准数据集和所生成的第一MR图像数据集导出第二组权重，并使用第二组权重来产生第二个 MR图像数据集表示相对于第一复合MR图像数据集具有减少的数据分量集合的单个图像。

公开(公告)号：US20150323628A1

公开(公告)日：2015-11-12

申请号：US14648485

申请日：2013-12-02

申请人： Lawrence WALD ,  Jason STOCKMANN

发明人： Lawrence Wald ,  Jason Stockmann

IPC分类号： G01R33/3875 ,  G01R33/341

CPC分类号： G01R33/3415 ,  A61B5/055 ,  G01R33/341 ,  G01R33/3875

摘要： A system and method for magnetic resonance imaging (MRI) and static field (B0) shimming. A coil system includes a conductive loop configured to be arranged proximate to a region of interest (ROI). The coil system also includes an alternating current (AC) circuit electrically connecting the conductive loop to an AC electrical connection configured to be coupled to an MRI system to communicate medical imaging signals received by the conductive loop from the ROI during a medical imaging procedure to the MRI system. The coil system further includes a direct current (DC) circuit electrically connecting the conductive loop to a DC electrical connection configured to be coupled to a DC power source and a plurality of circuit components configured to block DC signals from reaching the AC electrical connection in order to produce a spatially varying static magnetic field for shimming inhomogenieties of the static field.

摘要翻译： 用于磁共振成像（MRI）和静态场（B0）匀场的系统和方法。 线圈系统包括被布置成靠近感兴趣区域（ROI）布置的导电回路。 线圈系统还包括将导电回路电连接到AC电连接的交流电（AC）电路，AC电连接被配置为耦合到MRI系统，以将在医疗成像过程期间由导电回路接收的医学成像信号从ROI传送到ROI MRI系统。 线圈系统还包括直流（DC）电路，其将导电回路电连接到被配置为耦合到DC电源的DC电连接，以及多个电路部件，其被配置为阻止DC信号按顺序到达AC电连接 以产生空间变化的静磁场，用于匀场静电场的不均匀分布。

公开(公告)号：US20140292337A1

公开(公告)日：2014-10-02

申请号：US13918461

申请日：2013-06-14

申请人： Elfar Adalsteinsson ,  Luca Daniel ,  Bastien Guerin ,  Zohaib Mahmood ,  Markus Vester ,  Lawrence Wald

发明人： Elfar Adalsteinsson ,  Luca Daniel ,  Bastien Guerin ,  Zohaib Mahmood ,  Markus Vester ,  Lawrence Wald

IPC分类号： G01R33/36

CPC分类号： G01R33/365 ,  G01R33/5612

摘要： A method of determining a decoupling matrix of a decoupling system for an array of coils of a parallel transmission magnetic resonance imaging (MRI) system includes obtaining impedance matrix data for the array of coils without the decoupling system, determining, based on the impedance matrix data for the array of coils, an objective function representative of deviation from a decoupled operating condition for the array of coils in which the array of coils are decoupled via the decoupling system, and defining, with a processor, a decoupling matrix representative of a set of impedances of the decoupling system with an iterative procedure that optimizes elements of the decoupling matrix to minimize the objective function and reach the decoupled operating condition.

摘要翻译： 确定并行传输磁共振成像（MRI）系统的线圈阵列的去耦系统的去耦矩阵的方法包括：获得用于没有去耦系统的线圈阵列的阻抗矩阵数据，基于阻抗矩阵数据 对于线圈阵列，表示偏离线圈阵列的去耦工作条件的目标函数，其中线圈阵列经由去耦系统去耦，并且用处理器定义代表一组线圈的去耦矩阵 解耦系统的阻抗具有优化去耦矩阵的元素以最小化目标函数并达到解耦操作条件的迭代过程。

公开(公告)号：US08154289B2

公开(公告)日：2012-04-10

申请号：US12422512

申请日：2009-04-13

申请人： Adam C. Zelinski ,  Lawrence Wald ,  Elfar Adalsteinsson ,  Vivek K Goyal

发明人： Adam C. Zelinski ,  Lawrence Wald ,  Elfar Adalsteinsson ,  Vivek K Goyal

IPC分类号： G01V3/00

CPC分类号： G01R33/561 ,  G01R33/4824 ,  G01R33/4836 ,  G01R33/5611 ,  G01R33/5612

摘要： A system and method is provided for simultaneously designing a radiofrequency (“RF”) pulse waveform and a magnetic field gradient waveform in a magnetic resonance imaging (“MRI”) system. The method includes determining a desired pattern of RF excitation and determining, from the desired pattern of RF excitation, a plurality of k-space locations indicative of the magnetic field gradient waveform and a plurality of complex weighting factors indicative of RF energy deposited at each k-space location. The method also includes calculating, from the determined k-space locations, the magnetic field gradient waveform and calculating, from the complex weighting factors, the RF pulse waveform that will produce the desired pattern of RF excitation when produced with the calculated magnetic field gradient.

摘要翻译： 提供了一种在磁共振成像（“MRI”）系统中同时设计射频（“RF”）脉冲波形和磁场梯度波形的系统和方法。 该方法包括确定期望的RF激励模式，并根据所需的RF激励模式确定表示磁场梯度波形的多个k空间位置以及指示在每个k处沉积RF能量的多个复加权系数 - 空间位置。 该方法还包括从确定的k空间位置计算磁场梯度波形，并从复数加权因子计算当用所计算的磁场梯度产生时将产生期望的RF激励模式的RF脉冲波形。

公开(公告)号：US08076939B2

公开(公告)日：2011-12-13

申请号：US12422017

申请日：2009-04-10

申请人： Kawin Setsompop ,  Elfar Adalsteinsson ,  Vijayanand Alagappan ,  Lawrence Wald

发明人： Kawin Setsompop ,  Elfar Adalsteinsson ,  Vijayanand Alagappan ,  Lawrence Wald

IPC分类号： G01V3/00

CPC分类号： G01R33/583 ,  G01R33/246 ,  G01R33/3415 ,  G01R33/5611

摘要： A system and method for producing an image indicative of characteristics of a radiofrequency (“RF”) coil with a magnetic resonance imaging (“MRI”) system is disclosed. The method includes acquiring MR signals while performing a pulse sequence with the MRI system and driving the RF coil at a selected transmission power. This process is repeated a plurality of times to drive the RF coil at a different transmission powers during each repetition. A plurality of images are reconstructed from the acquired MR signals and an image indicative of RF reception characteristics of the RF coil is produced from the reconstructed images. Subsequently, an image indicative of RF transmission characteristics of the RF coil is produced using the image indicative of the RF receiver response. More specifically, only one data acquisition is necessary for each RF coil element to produce the image indicative of the RF transmission characteristics for that coil element.

摘要翻译： 公开了一种用于产生表示具有磁共振成像（“MRI”）系统的射频（“RF”）线圈的特性的图像的系统和方法。 该方法包括在用MRI系统执行脉冲序列并以选定的发射功率驱动RF线圈的同时获取MR信号。 该过程重复多次以在每次重复期间以不同的发送功率驱动RF线圈。 从所获取的MR信号重建多个图像，并且从重建图像产生表示RF线圈的RF接收特性的图像。 随后，使用表示RF接收机响应的图像来产生指示RF线圈的RF传输特性的图像。 更具体地，对于每个RF线圈元件仅需要一个数据采集来产生指示该线圈元件的RF传输特性的图像。