公开(公告)号：US20120153950A1

公开(公告)日：2012-06-21

申请号：US13390618

申请日：2010-08-05

申请人： Ulrich Katscher

发明人： Ulrich Katscher

IPC分类号： G01R33/44

CPC分类号： G01R33/5612 ,  G01R33/4824 ,  G01R33/4833 ,  G01R33/4836 ,  G01R33/5659

摘要： A radio-frequency (RF) shimming apparatus (50) for use in a magnetic resonance imaging (MRI) system (10) comprises of a spatial sensitivity unit (30) which determines a transmit spatial sensitivity distribution of at least one RF coil (18,18′). A selection unit (32) selects an excitation pattern with a through-plane, one-dimensional excitation k-space trajectory. The through-plane, one-dimensional excitation k-space trajectory is curved into at least a second dimension by an optimization unit (34) according to the generated spatial sensitivity distribution. The optimization unit (34) supplies the curved excitation k-space trajectory to at least one transmitter (24) which causes the at least one RF transmit coil (18,18′) to transmit the selected excitation pattern with the curved excitation k-space trajectory.

摘要翻译： 用于磁共振成像（MRI）系统（10）的射频（RF）匀场装置（50）包括空间灵敏度单元（30），其确定至少一个RF线圈（18）的发射空间灵敏度分布 ，18'）。 选择单元（32）选择具有贯穿平面，一维激励k空间轨迹的激励图案。 根据生成的空间灵敏度分布，通过平面的一维激发k空间轨迹由优化单元（34）弯曲成至少第二维度。 优化单元（34）将弯曲激励k空间轨迹提供给至少一个发射器（24），所述发射器（24）使得至少一个RF发射线圈（18,18'）将所选择的激励模式与弯曲激励k空间 弹道。

公开(公告)号：US20120139541A1

公开(公告)日：2012-06-07

申请号：US12933894

申请日：2009-03-25

申请人： Steffen Weiss ,  Ulrich Katscher ,  Peter Vernickel ,  Tobias Ratko Voigt ,  Christian Findeklee

发明人： Steffen Weiss ,  Ulrich Katscher ,  Peter Vernickel ,  Tobias Ratko Voigt ,  Christian Findeklee

IPC分类号： G01R33/44

CPC分类号： G01R33/583 ,  A61B5/055 ,  G01R33/288

摘要： A magnetic resonance imaging apparatus produces calculations of local specific energy absorption rates (SAR) by calculating an electrical permittivity map of a subject. The electric permittivity is calculated by measuring the components of the B1 field induced by a radio frequency (RF) coil (16). The Hx and Hy components of the B1 field can be directly measured. The Hz component is measured by encoding it into the phase of the resonance signals. Alternately, Hz can be calculated by solving Gauss's law for magnetism. Hz can also be estimated by finding the z component of the electric field. In the specific case of a birdcage RF coil, Hz can be estimated by using a model of the RF coil and a subject, a model of the RF coil alone, or setting Hz to a constant.

摘要翻译： 磁共振成像装置通过计算受试者的电容率图来产生局部比能吸收率（SAR）的计算。 通过测量由射频（RF）线圈（16）感应的B1场的分量来计算电容率。 可以直接测量B1场的Hx和Hy分量。 通过对谐振信号的相位进行编码来测量Hz分量。 或者，可以通过求解磁性的高斯定律来计算Hz。 Hz也可以通过找到电场的z分量来估计。 在鸟笼RF线圈的具体情况下，可以通过使用RF线圈和对象的模型，单独的RF线圈的模型或将Hz设置为常数来估计Hz。

公开(公告)号：US08049497B2

公开(公告)日：2011-11-01

申请号：US12446661

申请日：2007-10-31

申请人： Ulrich Katscher ,  Peter Vernickel ,  Peter Boernert

发明人： Ulrich Katscher ,  Peter Vernickel ,  Peter Boernert

IPC分类号： G01V3/00

CPC分类号： G01R33/4831 ,  G01R33/3415

摘要： A common method of RF encoding assumes that the B1 field generated by the RF coils is linear, which is likely not the case in many situations. It is therefore desirable to have a method of operating an MR system to reconstruct an image of a subject, wherein the method is capable of also handling arbitrary B1 fields used for RF encoding. Accordingly, such an MR system employing one or more RF coils is disclosed herein. The method comprises obtaining transmit sensitivities and weighting factors for individual RF coils. Each RF coil is activated based on its respective weighting factor to apply RF excitation to a subject under examination in the MR system. MR signals—such as free induction decays (FID) signals or echo signals—generated from the subject in response to the RF excitation are received and processed based on the transmit sensitivities to generate an MR image or spectrum representative of the subject.

摘要翻译： RF编码的常见方法假定由RF线圈产生的B1场是线性的，这在许多情况下可能不是这种情况。 因此，期望具有操作MR系统以重建对象的图像的方法，其中该方法还能够处理用于RF编码的任意B1字段。 因此，这里公开了采用一个或多个RF线圈的这种MR系统。 该方法包括获得单个RF线圈的发射灵敏度和加权因子。 每个RF线圈基于其相应的加权因子被激活，以将RF激励施加到在MR系统中被检查的受试者。 基于发射灵敏度接收和处理MR信号，例如响应于RF激励从受试者产生的自由感应衰减（FID）信号或回波信号，以产生代表对象的MR图像或频谱。

公开(公告)号：US07375524B2

公开(公告)日：2008-05-20

申请号：US10560872

申请日：2004-06-01

申请人： Ulrich Katscher ,  Mark J. Loncar ,  Michael R. Thompson

发明人： Ulrich Katscher ,  Mark J. Loncar ,  Michael R. Thompson

IPC分类号： G01V3/00

CPC分类号： G01R33/5611

摘要： A magnetic resonance imaging system acquires a final image of a selected field of view with a selected spatial resolution. A magnetic resonance imaging scanner (10) encodes and receives magnetic resonance samples in phase encode and readout directions using a plurality of receive coils (14). The encoding and receiving undersamples in the readout direction. A reconstruction processor (30) reconstructs magnetic resonance samples acquired by each of the plurality of receive coils (14) into a corresponding plurality of intermediate reconstructed images. Each intermediate reconstructed image has aliasing and in some aspects degraded high spatial frequency characteristics due to the reduced sampling in the readout direction. A combining processor (40) combines the plurality of intermediate reconstructed images based on coil sensitivity factors (42) to produce the final reconstructed image with the selected field of view and the selected spatial resolution in the readout direction.

摘要翻译： 磁共振成像系统以所选择的空间分辨率获取所选视场的最终图像。 磁共振成像扫描器（10）使用多个接收线圈（14）对相位编码和读出方向的磁共振样本进行编码和接收。 在读出方向编码和接收欠采样。 重建处理器（30）将由多个接收线圈（14）中的每一个获取的磁共振样本重建成相应的多个中间重建图像。 每个中间重建图像具有混叠，并且在一些方面由于在读出方向上的采样减少而导致高空间频率特性降低。 组合处理器（40）基于线圈灵敏度因子（42）组合多个中间重建图像，以产生具有所选视场的最终重建图像，并且在读出方向上产生所选择的空间分辨率。

公开(公告)号：US08390288B2

公开(公告)日：2013-03-05

申请号：US12598451

申请日：2008-04-24

申请人： Ingmar Graesslin ,  Peter Boernert ,  Peter Vernickel ,  Ulrich Katscher

发明人： Ingmar Graesslin ,  Peter Boernert ,  Peter Vernickel ,  Ulrich Katscher

IPC分类号： G01V3/00

CPC分类号： G01R33/34046 ,  G01R33/288 ,  G01R33/3415 ,  G01R33/543 ,  G01R33/5604 ,  G01R33/5611 ,  G01R33/5659

摘要： A multi-channel RF transmitter arrangement comprising a plurality of RF transmitter elements like RE antennas, antenna elements, coils or coil elements, for generating an RF field, especially for use in a magnetic resonance imaging system for exciting nuclear magnetic resonances, and a method for generating such an RF field wherein the RF transmitter elements are segmented in a plurality of segments at least along the direction of one or more of the main magnetic field of the MRI system, the z-direction or the longitudinal direction.

摘要翻译： 包括多个RF发射器元件的多通道RF发射器装置，如RE天线，天线元件，线圈或线圈元件，用于产生RF场，特别是用于激励核磁共振的磁共振成像系统，以及方法 用于产生这样的RF场，其中RF发射器元件至少沿着MRI系统的主磁场，z方向或纵向方向中的一个或多个的方向被分段成多个段。

公开(公告)号：US07839147B2

公开(公告)日：2010-11-23

申请号：US12297662

申请日：2007-11-08

申请人： Ulrich Katscher ,  Peter Vernickel ,  Marius Hanft

发明人： Ulrich Katscher ,  Peter Vernickel ,  Marius Hanft

IPC分类号： G01V3/00

CPC分类号： G01R33/48 ,  A61B5/0536 ,  G01R33/4808

摘要： A radio frequency coil system (34) used in the context of electric properties tomography (EPT, electrical impedance tomography, EIT, applied potential tomography, APT) generates radio frequency excitation pulses in an examination region (14). The radio frequency coil system (34) includes N coil elements (38) which generate magnetic (H) and electric (E) fields. A weight setting device (54) sets weight factors for input signals for the coil elements (38). A transmitting system (52) creates RF pulses, at least two sets of each with differently weighted input signals, and transmits the at least two sets of RF pulses to the coil elements (38) such that each of the transmitted RF pulse sets generates shifted electric fields (110, 112) having a shifted zero crossing point (120, 122) from each other. An image processor (62) computes electric permittivity maps from resonance induced by the at least two sets of RF pulses with different weighting.

摘要翻译： 在电性能断层摄影（EPT，电阻断层扫描，EIT，应用电位层析成像，APT）的上下文中使用的射频线圈系统（34）在检查区域（14）中产生射频激励脉冲。 射频线圈系统（34）包括产生磁（H）和电（E）场的N个线圈元件（38）。 权重设定装置（54）为线圈元件（38）的输入信号设定权重因子。 发射系统（52）产生RF脉冲，每个具有不同加权的输入信号的至少两组，并且将至少两组RF脉冲发送到线圈元件（38），使得每个发射的RF脉冲组产生偏移 具有彼此偏移的零交叉点（120,122）的电场（110,112）。 图像处理器（62）从具有不同加权的至少两组RF脉冲引起的共振计算电容率图。

公开(公告)号：US20090102480A1

公开(公告)日：2009-04-23

申请号：US12297662

申请日：2007-04-03

申请人： Ulrich Katscher ,  Peter Vernickel ,  Marius Hanft

发明人： Ulrich Katscher ,  Peter Vernickel ,  Marius Hanft

IPC分类号： G01R33/48

CPC分类号： G01R33/48 ,  A61B5/0536 ,  G01R33/4808

摘要： A radio frequency coil system (34) used in the context of electric properties tomography (EPT, electrical impedance tomography, EIT, applied potential tomography, APT) generates radio frequency excitation pulses in an examination region (14). The radio frequency coil system (34) includes N coil elements (38) which generate magnetic (H) and electric (E) fields. A weight setting device (54) sets weight factors for input signals for the coil elements (38). A transmitting system (52) creates RF pulses, at least two sets of each with differently weighted input signals, and transmits the at least two sets of RF pulses to the coil elements (38) such that each of the transmitted RF pulse sets generates shifted electric fields (110, 112) having a shifted zero crossing point (120, 122) from each other. An image processor (62) computes electric permittivity maps from resonance induced by the at least two sets of RF pulses with different weighting.

摘要翻译： 在电性能断层摄影（EPT，电阻断层扫描，EIT，应用电位层析成像，APT）的上下文中使用的射频线圈系统（34）在检查区域（14）中产生射频激励脉冲。 射频线圈系统（34）包括产生磁（H）和电（E）场的N个线圈元件（38）。 权重设定装置（54）为线圈元件（38）的输入信号设定权重因子。 发射系统（52）产生RF脉冲，每个具有不同加权的输入信号的至少两组，并且将至少两组RF脉冲发送到线圈元件（38），使得每个发射的RF脉冲组产生偏移 具有彼此偏移的零交叉点（120,122）的电场（110,112）。 图像处理器（62）从具有不同加权的至少两组RF脉冲引起的共振计算电容率图。

公开(公告)号：US07176686B2

公开(公告)日：2007-02-13

申请号：US10498594

申请日：2002-12-19

申请人： Ulrich Katscher ,  Peter Boernert

发明人： Ulrich Katscher ,  Peter Boernert

IPC分类号： G01V3/00

CPC分类号： G01R33/5611

摘要： The invention relates to a parallel MR imaging method in which first a first MR imaging sequence is formed with a selectable minimum number of phase encoding steps and at least two separate MR signal data sets are acquired by means of at least two MR receiving coils. A first MR image is reconstructed from this data while taking into account the spatial sensitivity profiles of the MR receiving coils. In order to improve parallel MR imaging methods of this kind, the invention proposes to evaluate the quality of the reconstructed MR image in a subsequent step of the method and, in dependence upon the result of the evaluation, to either terminate the imaging method or to form a further MR imaging sequence with a number of further phase encoding steps. This procedure can be continued until an adequate MR image quality is reached.

摘要翻译： 本发明涉及一种并行MR成像方法，其中首先通过可选择的最小数量的相位编码步骤形成第一MR成像序列，并且借助于至少两个MR接收线圈获取至少两个单独的MR信号数据集。 从该数据重建第一MR图像，同时考虑MR接收线圈的空间灵敏度分布。 为了改进这种并行MR成像方法，本发明提出了在该方法的后续步骤中评价重建MR图像的质量，并且根据评估结果来终止成像方法或者终止成像方法 形成具有多个进一步的相位编码步骤的另外的MR成像序列。 可以继续该过程，直到达到足够的MR图像质量。

公开(公告)号：US09702950B2

公开(公告)日：2017-07-11

申请号：US14238999

申请日：2012-08-15

申请人： Hanno Heyke Homann ,  Ingmar Graesslin ,  Ulrich Katscher ,  Tobias Ratko Voigt ,  Olaf Helmut Dössel ,  Sebastian Alfred Seitz

发明人： Hanno Heyke Homann ,  Ingmar Graesslin ,  Ulrich Katscher ,  Tobias Ratko Voigt ,  Olaf Helmut Dössel ,  Sebastian Alfred Seitz

IPC分类号： G01R33/28 ,  G01R33/36 ,  G01R33/561

CPC分类号： G01R33/36 ,  G01R33/285 ,  G01R33/288 ,  G01R33/5612

摘要： A magnetic resonance imaging system (300) acquires magnetic resonance data (358) from a subject (318) that may include an electrically conductive object (e.g. an implant or a medical device). The magnetic resonance imaging system includes a radio-frequency transmitter (314) for generating a radio-frequency transmit field for acquiring the magnetic resonance data using a radio-frequency antenna (310). The radio-frequency transmitter has multiple transmit channels. The radio-frequency antenna comprises multiple antenna elements (312) each adapted to connect to an antenna element. The amplitude and phase values of the RF transmit field of each of the transmit channels can be selected such that the magnetic field generated by the RF antenna is minimized at the location of the electrically conductive object, thereby reducing RF heating of the object.

公开(公告)号：US20120169333A1

公开(公告)日：2012-07-05

申请号：US13394566

申请日：2010-08-16

申请人： Ulrich Katscher ,  Peter Boernert ,  Christian Stehning ,  Ingmar Graesslin

发明人： Ulrich Katscher ,  Peter Boernert ,  Christian Stehning ,  Ingmar Graesslin

IPC分类号： G01R33/025

CPC分类号： G06T7/246 ,  G06T2207/10072 ,  G06T2207/30048

摘要： The invention relates to a motion monitoring system (1) for monitoring motion within a region of interest (2). The motion monitoring system (1) comprises a magnetic induction tomography detection data acquisition unit (3) for acquiring MIT detection data of the region of interest (2), and a motion determining unit (4) for determining motion within the region of interest (2) based on the acquired MIT detection data. The invention relates further to an imaging system for imaging a region of interest comprising the motion monitoring system (1). The determined motion can be used for reducing motion artifacts in reconstructed images.

摘要翻译： 本发明涉及一种用于监视感兴趣区域（2）内的运动的运动监视系统（1）。 运动监视系统（1）包括用于获取感兴趣区域（2）的MIT检测数据的磁感应断层摄影检测数据获取单元（3）和用于确定感兴趣区域内的运动的运动确定单元（4） 2）基于所获得的MIT检测数据。 本发明进一步涉及用于对包括运动监视系统（1）的兴趣区域进行成像的成像系统。 所确定的运动可用于减少重建图像中的运动伪影。