公开(公告)号：US20070255128A1

公开(公告)日：2007-11-01

申请号：US11734898

申请日：2007-04-13

申请人： Juergen Nistler

发明人： Juergen Nistler

IPC分类号： A61B5/05

CPC分类号： G01R33/3415 ,  G01R33/246 ,  G01R33/5659

摘要： In al magnetic resonance system and a method for operating the magnetic resonance system to set RF transmit parameters for a radio-frequency antenna that is excitable in a number of different, linearly independent transmit modes, the transmit antenna is successively caused to be excited in the different transmit modes, and, for each transmit mode in which the radio-frequency antenna is excited, a measured value distribution representing the radio-frequency field produced by the antenna in a defined volume area is determined. The homogeneity of the measured value distribution is evaluated with respect to a defined evaluation criterion and, if the evaluation criterion is satisfied, an optimized radio-frequency field distribution is determined from a combination of the measured value distributions up to that time. If the evaluation criterion is not fulfilled, the radio-frequency antenna is excited with a further transmit mode, and the procedure is repeated.

摘要翻译： 在磁共振系统和用于操作磁共振系统以设置在多个不同的线性独立的发射模式中可激发的射频天线的RF发射参数的方法中，发射天线被连续地在 不同的发射模式，并且对于其中激发射频天线的每个发射模式，确定表示在限定的体积区域中由天线产生的射频场的测量值分布。 根据定义的评价标准评价测定值分布的均匀性，如果满足评价标准，则从直到该时刻的测定值分布的组合来确定优化的射频场分布。 如果不满足评价标准，则以进一步的发送模式激励射频天线，重复该过程。

公开(公告)号：US20070247158A1

公开(公告)日：2007-10-25

申请号：US11737214

申请日：2007-04-19

申请人： Juergen Nistler ,  Wolfgang Renz ,  Markus Vester

发明人： Juergen Nistler ,  Wolfgang Renz ,  Markus Vester

IPC分类号： G01V3/00

CPC分类号： G01R33/34046 ,  G01R33/34076 ,  G01R33/3415 ,  G01R33/365 ,  G01R33/3657 ,  G01R33/3685 ,  G01R33/422 ,  G01R33/5659

摘要： A cylindrical magnetic resonance antenna suitable for use as a local antenna for the reception or transmission of magnetic resonance signals, has an antenna arrangement, such as a birdcage antenna arrangement with longitudinal conductors connected at their opposite ends by end rings. In each case, two adjacent longitudinal conductors and the end ring segments therebetween form a network. In each case, the end ring segments connecting two of the adjacent longitudinal conductors are formed as end ring sections, with an end ring capacitance connected therebetween, which is the same for all of the end ring segments. A grounded screen externally encompasses the antenna arrangement. The grounded screen is composed of electrically conductive material and is coupled through a screen capacitance to the longitudinal conductors and the end rings. The longitudinal conductors are each formed by conductor sections connected with a longitudinal capacitance therebetween, which is the same for all of the longitudinal conductors. The longitudinal capacitance, the end ring capacitance, and the screen capacitance are dimensioned so that the magnetic resonance antenna always has the same resonance frequency regardless of the type of activation thereof.

摘要翻译： 适合用作接收或传输磁共振信号的本地天线的圆柱形磁共振天线具有天线布置，例如鸟笼天线装置，其纵向导体在其相对端通过端环连接。 在每种情况下，两个相邻的纵向导体和其间的端环段形成网络。 在每种情况下，连接两个相邻的纵向导体的端环段形成为端环部分，端环电容连接在它们之间，对于所有端环段是相同的。 外部接地屏幕包括天线装置。 接地屏幕由导电材料组成，并通过屏蔽电容耦合到纵向导体和端环。 纵向导体各自由与其间的纵向电容连接的导体部分形成，这对于所有纵向导体是相同的。 纵向电容，端环电容和屏幕电容的尺寸使得磁共振天线始终具有相同的谐振频率，而与其激活类型无关。

公开(公告)号：US06825662B2

公开(公告)日：2004-11-30

申请号：US10348296

申请日：2003-01-21

申请人： Juergen Nistler ,  Wolfgang Renz

发明人： Juergen Nistler ,  Wolfgang Renz

IPC分类号： G01V300

CPC分类号： H05K9/0069

摘要： In a method and apparatus for continuously, directly monitoring the RF-tightness of a shielded cubicle of an MR system, a radio-frequency signal is transmitted to the cubicle from the outside via an antenna and the signal part that passes to the interior is identified with a receiver in the inside of the cubicle. An RF transmission antenna arranged at the outside in the door region of the shielded cubicle is connected to an RF output of the MR system, and a body coil of the MR system is employed as a reception antenna for determining the RF tightness of the shielded cubicle of the MR system, and is connected to a monitoring receiver.

摘要翻译： 在用于连续地直接监视MR系统的屏蔽隔间的RF密封性的方法和装置中，射频信号经由天线从外部传输到隔间，并且识别出传递到内部的信号部分 在柜子里面有一个接收器。 布置在屏蔽室的门区域中的外部的RF发送天线连接到MR系统的RF输出，并且MR系统的体线圈用作用于确定屏蔽柜的RF紧密度的接收天线 的MR系统，并且连接到监视接收器。

公开(公告)号：US06242917B1

公开(公告)日：2001-06-05

申请号：US09497638

申请日：2000-02-03

申请人： Juergen Nistler ,  Wolfgang Renz

发明人： Juergen Nistler ,  Wolfgang Renz

IPC分类号： G01V300

CPC分类号： H01Q21/24

摘要： A magnetic resonance transmission antenna has at least two transmission elements that independently respectively generate a linearly polarized, discrete magnetic field, which are superimposed to form an overall magnetic field. The transmission elements are coupled to one another such that a transmission current fed into one of the transmission elements generates a coupled current in the other of the transmission elements, so that the overall magnetic field generated by the transmission elements is circularly polarized.

摘要翻译： 磁共振发射天线具有至少两个独立地分别产生线性极化的离散磁场的传输元件，它们叠加形成整个磁场。 传输元件彼此耦合，使得馈送到传输元件之一的传输电流在另一个传输元件中产生耦合电流，使得由传输元件产生的整个磁场是圆极化的。

公开(公告)号：US08358131B2

公开(公告)日：2013-01-22

申请号：US12718271

申请日：2010-03-05

申请人： Razvan Lazar ,  Juergen Nistler

发明人： Razvan Lazar ,  Juergen Nistler

IPC分类号： G01V3/30 ,  G01R33/32 ,  A61B6/00

CPC分类号： G01R33/3628 ,  G01R33/3415 ,  G01R33/3456

摘要： The efficiency and the field structure of an antenna arrangement for a magnetic resonance tomography apparatus are improved by at least one impedance transformation circuit connected with the antenna.

摘要翻译： 用于磁共振断层摄影装置的天线装置的效率和场结构由与天线连接的至少一个阻抗变换电路改进。

公开(公告)号：US08120359B2

公开(公告)日：2012-02-21

申请号：US12487748

申请日：2009-06-19

申请人： Dirk Diehl ,  Rene Gumbrecht ,  Juergen Nistler ,  Wolfgang Renz ,  Markus Vester ,  Sebastian Wolf

发明人： Dirk Diehl ,  Rene Gumbrecht ,  Juergen Nistler ,  Wolfgang Renz ,  Markus Vester ,  Sebastian Wolf

IPC分类号： G01V3/00

CPC分类号： G01R33/3415 ,  A61B5/055 ,  G01R33/288 ,  G01R33/4833 ,  G01R33/5612 ,  G01R33/5659

摘要： In a magnetic resonance apparatus having an RF radiating coil and gradient coils, and in a method for operating such a magnetic resonance apparatus, a pulse sequence, composed of multiple time steps, is specified for operating the gradient coils to time-dependently select regions of a selected slice of a selected volume of a subject. A non-linear equation system is then solved to obtain feed parameters for individual channels of the transmit coil for each time step, with specification of a desired target magnetization, and dependent on the pulse sequence specified for the gradient coils. The non-linear equation system is based on discrete values for time and space variable and, in addition to equations resulting from the Bloch equation, which are non-linear in their feed parameters, includes at least one additional equation that describes boundary conditions for the examination of the subject.

摘要翻译： 在具有RF辐射线圈和梯度线圈的磁共振装置中，并且在用于操作这种磁共振装置的方法中，规定了由多个时间步长组成的脉冲序列，用于操作梯度线圈以时间依次选择 所选择的受试者体积的切片。 然后解决非线性方程式，以获得每个时间步长的发射线圈的各个通道的馈送参数，并且具有期望的目标磁化强度，并且取决于为梯度线圈指定的脉冲序列。 非线性方程系统基于时间和空间变量的离散值，并且除了在其馈送参数中是非线性的由Bloch方程得到的方程之外，还包括至少一个附加方程，其描述了 考试题目。

公开(公告)号：US07986142B2

公开(公告)日：2011-07-26

申请号：US12358498

申请日：2009-01-23

申请人： Ludwig Eberler ,  Juergen Nistler

发明人： Ludwig Eberler ,  Juergen Nistler

IPC分类号： G01V3/00

CPC分类号： G01R33/34076 ,  G01R33/3678 ,  G01R33/5659

摘要： A cylindrical antenna arrangement in a magnetic resonance apparatus has two feed points to feed in two partial signals, the two feed points being arranged on a cross-section of the antenna arrangement. The cross-section has a center point. A first angle is formed by the connection of a first feed point with the center point relative to a horizontal axis of the cross-section while a second angle is formed by the connection of a second feed point with the center point relative to the horizontal axis of the cross-section. An apparatus for controlling such an antenna arrangement has a device for signal splitting with two outputs and an input. A radio-frequency magnetic resonance signal is connected at the input. This signal is divided by the device for signal splitting into two partial signals of equal amplitude that are respectively supplied to an associated output. Each output of the device for signal splitting is connected with precisely one associated feed point of the antenna arrangement. An ellipse position in space is set for an elliptical polarization via the selection of the two angles. A device for phase adjustment is interposed between precisely one output of the device for signal splitting and the associated feed point in order to set an elliptical semi-axis ratio via variation of the phase difference of the two partial signals.

摘要翻译： 磁共振装置中的圆柱形天线装置具有两个馈送点，以馈送两个部分信号，两个馈送点布置在天线装置的横截面上。 横截面有一个中心点。 通过第一馈电点与中心点相对于横截面的水平轴线的连接形成第一角度，而第二角度通过第二馈电点与中心点相对于水平轴线的连接而形成 的横截面。 用于控制这种天线装置的装置具有用于具有两个输出和输入的信号分离的装置。 射频磁共振信号在输入端连接。 该信号由用于信号分解的装置分成两个分别提供给相关联的输出的相等幅度的部分信号。 用于信号分离的设备的每个输出端与天线装置的精确一个相关馈电点相连。 通过选择两个角度来设置空间中的椭圆位置用于椭圆偏振。 用于相位调整的装置插入用于信号分离的装置的精确一个输出端和相关联的馈电点之间，以便通过两个部分信号的相位差的变化来设定椭圆半轴比。

公开(公告)号：US07902821B2

公开(公告)日：2011-03-08

申请号：US11734898

申请日：2007-04-13

申请人： Juergen Nistler

发明人： Juergen Nistler

IPC分类号： G01V3/00

CPC分类号： G01R33/3415 ,  G01R33/246 ,  G01R33/5659

摘要： In a magnetic resonance system and operating method to set RF transmit parameters for a radio-frequency antenna that is excitable in a number of different, linearly independent transmit modes, the transmit antenna is successively excited in the different transmit modes, and, for each transmit mode in which the radio-frequency antenna is excited, a measured value distribution representing the radio-frequency field produced by the antenna in a defined volume area is determined. The homogeneity of the measured value distribution is evaluated with respect to a defined evaluation criterion and, if the evaluation criterion is satisfied, an optimized radio-frequency field distribution is determined from a combination of the measured value distributions up to that time. If the evaluation criterion is not fulfilled, the radio-frequency antenna is excited with a further transmit mode, and the procedure is repeated.

摘要翻译： 在磁共振系统和操作方法中，为在多个不同的线性无关的发射模式中兴奋的射频天线设置射频发射参数，发射天线在不同的发射模式下被连续地激发，并且对于每个发射 射频天线被激励的模式，确定表示由限定容积区域中的天线产生的射频场的测量值分布。 根据定义的评价标准评价测定值分布的均匀性，如果满足评价标准，则从直到该时刻的测定值分布的组合来确定优化的射频场分布。 如果不满足评价标准，则以进一步的发送模式激励射频天线，重复该过程。

公开(公告)号：US20100167668A1

公开(公告)日：2010-07-01

申请号：US12641651

申请日：2009-12-18

申请人： Juergen Nistler ,  Markus Vester

发明人： Juergen Nistler ,  Markus Vester

IPC分类号： H04B1/02

CPC分类号： G01R33/48 ,  G01R33/288 ,  G01R33/34076 ,  G01R33/3415 ,  G01R33/3628

摘要： In a method and device for monitoring a radio-frequency transmit device of a magnetic resonance tomography system, having a transmitter antenna system that has a number of transmit channels, during a magnetic resonance measurement of an examination subject, a reference scattering parameter matrix of the transmitter antenna system is determined in the unloaded state, and a subject-specific scattering parameter matrix of the transmitter antenna system is determined in a state loaded with the subject of examination. Moreover, transmitter amplitude vectors are determined in time-dependent fashion that represent the radio-frequency voltage amplitudes on the individual transmit channels. On the basis of the subject-specific scattering parameter matrix, the reference scattering parameter matrix, and the transmit amplitude vectors, radio-frequency power values absorbed at particular transmit times in the subject are determined. Based on a large number of the determined radio-frequency power values, a number of monitoring values are formed. The radio-frequency transmit device is limited in its functioning when a monitoring value reaches or exceeds a prespecified boundary monitoring value.

摘要翻译： 在用于监测磁共振断层摄影系统的射频发射装置的方法和装置中，在检查对象的磁共振测量期间具有具有多个发射信道的发射机天线系统， 在无负载状态下确定发射机天线系统，并且在负载有检查对象的状态下确定发射机天线系统的主题特定散射参数矩阵。 此外，发射机幅度矢量以表示各个发射信道上的射频电压振幅的时间依赖方式确定。 基于主题特定散射参数矩阵，确定参考散射参数矩阵和发射幅度矢量，在被摄体中的特定发射时间吸收的射频功率值。 基于大量确定的射频功率值，形成多个监视值。 当监测值达到或超过预先指定的边界监测值时，射频发射设备的功能受到限制。

公开(公告)号：US07719281B2

公开(公告)日：2010-05-18

申请号：US12051923

申请日：2008-03-20

申请人： Joerg Ulrich Fontius ,  Marian Lattka ,  Juergen Nistler ,  Franz Schmitt

发明人： Joerg Ulrich Fontius ,  Marian Lattka ,  Juergen Nistler ,  Franz Schmitt

IPC分类号： G01V3/00

CPC分类号： G01R33/36 ,  G01R33/34046 ,  G01R33/3415 ,  G01R33/3607 ,  G01R33/5612 ,  G01R33/5659

摘要： In a method for controlling a magnetic resonance system having a radio-frequency antenna structure and a number of individually controllable transmission channels, respective parallel radio-frequency signals are emitted via the transmission channels for generation of a desired radio-frequency field distribution in at least one specific volume region within an examination volume of the magnetic resonance system. A digital signal is generated for each of the transmission channels and is modulated on a carrier frequency. The radio-frequency signal so generated is transmitted via a radio-frequency signal path to the radio-frequency antenna structure and is amplified therein in a radio-frequency power amplifier. The digital signal is manipulated in a characteristic curve correction device on the basis of a correction characteristic curve predetermined for the respective radio-frequency signal path such that a distortion of the radio-frequency signal caused in the appertaining radio-frequency signal path is at least partially compensated. Respective individual correction characteristic curves for a specific measurement are predetermined for the various transmission channels dependent on a field distribution parameter that defines the desired radio-frequency field distribution. A magnetic resonance system implements such a method.

摘要翻译： 在一种用于控制具有射频天线结构和多个可独立控制的传输信道的磁共振系统的方法中，经由传输信道发射各自的并行射频信号，用于至少产生所需的射频场分布 在磁共振系统的检查体积内的一个比体积区域。 为每个传输信道生成数字信号，并在载波频率上进行调制。 如此生成的射频信号经由射频信号路径发送到射频天线结构，并且在射频功率放大器中被放大。 基于针对各个射频信号路径预定的校正特性曲线，在特性曲线校正装置中操作数字信号，使得在相应射频信号路径中引起的射频信号的失真至少为 部分补偿。 根据限定期望的射频场分布的场分布参数，针对各种传输信道预先确定特定测量的各自的校正特性曲线。 磁共振系统实现这种方法。