公开(公告)号：US06414488B1

公开(公告)日：2002-07-02

申请号：US09516978

申请日：2000-03-01

申请人： Thomas Chmielewski

发明人： Thomas Chmielewski

IPC分类号： G01V300

CPC分类号： G01R33/3657

摘要： A magnetic resonance imaging apparatus creates images by exciting magnetic resonance in selected nuclei disposed within an image region. Through the image region a main magnetic field (B0) is applied and transverse gradients are produced. At selected times a high power RF pulse is applied to the imaging region causing the selected nuclei to resonate. These magnetic resonance signals are detected by a receive coil (D1, D2) and converted into an image representation viewable on a display (24). Images are obtained by repeating the transmit and receive portions until enough image data is received to produce an image. The receive coil (D1, D2) includes first decoupler circuits (28) arranged about the coil. During the transmit portion of the cycle, the decoupler circuits sense the high power RF pulse and decouple the coil. High speed switching diodes or PIN diodes are excited by the transmit RF pulse to switch inductors (40) into the coil to decouple the receive coil. During a receive portion of a cycle in which the coil is not used, a DC bias is selectively applied to the coil forcing the diodes on, actively decoupling the coil. The DC bias also biases a diode switch (50, 50′) to short the input of a preamplifier element (48, 48′) providing protection.

摘要翻译： 磁共振成像装置通过在设置在图像区域内的所选择的核中激发磁共振来产生图像。 通过图像区域施加主磁场（B0）并产生横向梯度。 在选定的时间，将高功率RF脉冲施加到成像区域，导致所选择的核谐振。 这些磁共振信号由接收线圈（D1，D2）检测并转换成可在显示器（24）上显示的图像表示。 通过重复发送和接收部分直到获得足够的图像数据以产生图像来获得图像。 接收线圈（D1，D2）包括绕线圈布置的第一去耦电路（28）。 在循环的发射部分期间，去耦电路感测高功率RF脉冲并使线圈解耦。 高速开关二极管或PIN二极管被发射RF脉冲激发，以将电感器（40）切换到线圈中以使接收线圈去耦。 在不使用线圈的周期的接收部分期间，选择性地将DC偏压施加到强制二极管的线圈上，主动地使线圈解耦。 DC偏压还偏置二极管开关（50,50'）以缩短提供保护的前置放大器元件（48,48'）的输入。

公开(公告)号：US09013185B2

公开(公告)日：2015-04-21

申请号：US13407852

申请日：2012-02-29

申请人： Robert W. Brown ,  Yong Wu ,  Zhen Yao ,  Shmaryu Shvarstsman ,  Thomas Chmielewski ,  Timothy Eagan

发明人： Robert W. Brown ,  Yong Wu ,  Zhen Yao ,  Shmaryu Shvarstsman ,  Thomas Chmielewski ,  Timothy Eagan

IPC分类号： G01R33/422 ,  G01R33/565

CPC分类号： G01R33/422 ,  G01R33/341 ,  G01R33/385 ,  G01R33/4822 ,  G01R33/56518 ,  Y10T83/505

摘要： Radio frequency (RF) shields used with magnetic resonance imaging (MRI) apparatus may experience gradient field induced eddy currents and RF field induced eddy currents. These eddy currents can cause the RF shield to heat up at an undesirable rate. RF shields are designed to have a desired degree of RF shielding and a desired heating attribute. Design goals for RF shields include gradient field transparency and RF field opacity, both of which can be influenced by eddy currents. Example methods identify a gradient field that will induce eddy currents and identify an RF field that will induce eddy currents. If a region on the RF shield is identified where the desired heating attribute will not be achieved, then a pattern of axial cuts and azimuthal cuts can be made in the RF shield to reduce gradient eddy current heating in the RF shield while maintaining desired RF shielding.

摘要翻译： 与磁共振成像（MRI）装置一起使用的射频（RF）屏蔽可能会经历梯度场感应涡流和射频场感应涡流。 这些涡流可以使RF屏蔽以不期望的速率加热。 RF屏蔽被设计为具有期望的RF屏蔽程度和期望的加热属性。 RF屏蔽的设计目标包括梯度场透明度和RF场不透明度，这两者都可以受涡流影响。 示例性方法识别将引起涡流的梯度场，并识别将产生涡流的RF场。 如果RF屏蔽上的区域被识别出将不能实现所需的加热属性，则可以在RF屏蔽中进行轴向切割和方位切割的图案，以减少RF屏蔽中的梯度涡流加热，同时保持所需的RF屏蔽 。

公开(公告)号：US20070090840A1

公开(公告)日：2007-04-26

申请号：US10560216

申请日：2004-05-28

申请人： Thomas Chmielewski ,  John Carlon

发明人： Thomas Chmielewski ,  John Carlon

IPC分类号： G01V3/00

CPC分类号： G01R33/34046

摘要： A split-top RF coil is provided. The split-top RF coil includes a first housing (80) having a first RF coil portion (41) disposed therein and a second housing (84) having a second RF coil portion (42) disposed therein. A plurality of slides (100) are disposed on at least one of the housings and a plurality of slide tracks (101) are disposed the housing opposite the slides for receiving the slides. The first and second housings are mechanically coupled via the slides and slide tracks. The RF coil also includes a plurality of electric connector pins (110) disposed on at least one of the housings and a plurality of pin receivers (111) disposed on the housing opposite the pins for receiving the conductor pins. Electric connections between the first and second coil RF coil portions are made via the pins and receivers.

摘要翻译： 提供分体式射频线圈。 分体RF线圈包括具有设置在其中的第一RF线圈部分（41）的第一壳体（80）和设置在其中的具有第二RF线圈部分（42）的第二壳体（84）。 多个滑动件（100）设置在至少一个壳体上，并且多个滑动轨道（101）设置在与滑块相对的壳体上，用于接收滑块。 第一和第二壳体通过滑块和滑动轨道机械耦合。 RF线圈还包括设置在至少一个壳体上的多个电连接器插脚（110）和设置在壳体上的与插脚相对的多个针式接收器（111），用于接收导体引脚。 第一和第二线圈RF线圈部分之间的电连接经由引脚和接收器进行。

公开(公告)号：US06377044B1

公开(公告)日：2002-04-23

申请号：US09516644

申请日：2000-03-01

申请人： Michael Burl ,  John W. Missal ,  Thomas Chmielewski

发明人： Michael Burl ,  John W. Missal ,  Thomas Chmielewski

IPC分类号： G01V300

CPC分类号： G01R33/3664 ,  G01R33/34 ,  G01R33/3415 ,  G01R33/3678

摘要： A magnetic resonance apparatus includes a multi-mode receiver assembly which facilitates operation in both a quadrature combination mode and phased array mode. The multi-mode receiver assembly includes a receiver coil assembly (30) comprising a first RF coil assembly (32) and a second RF coil assembly (34). A signal combining circuit, which includes a switch means, performs at least one of combining and splitting magnetic resonance signals received by the first and second RF coil assemblies (30, 32). The application of a DC bias potential to the switch means switches the multi-mode receiver assembly into the quadrature combination mode in which the received magnetic resonance signals are phase shifted and combined into a quadrature signal and an anti-quadrature signal. The absence of a DC bias potential to the switch means switches the multi-mode receiver assembly into the phased array mode in which the received magnetic resonance signals are phase shifted and passed individually to corresponding receivers. The multi-mode capability of the receiver assembly allows an operator to switch from a quadrature mode, which is provides faster reconstruction, to a phased array mode, which provides better image quality, within a single examination.

摘要翻译： 磁共振装置包括便于在正交组合模式和相控阵列模式下操作的多模式接收器组件。 多模式接收器组件包括包括第一RF线圈组件（32）和第二RF线圈组件（34）的接收器线圈组件（30）。 包括开关装置的信号组合电路执行由第一和第二RF线圈组件（30,32）接收的磁共振信号的组合和分割中的至少一个。 将DC偏置电位施加到开关装置将多模式接收器组件切换到正交组合模式，其中所接收的磁共振信号被相移并组合成正交信号和反正交信号。 对开关装置没有DC偏置电位将多模式接收器组件切换到相控阵模式，其中所接收的磁共振信号被相移并单独传递到对应的接收器。 接收器组件的多模式能力允许操作者在单次检查中从提供更快重建的正交模式切换到提供更好图像质量的相控阵列模式。

公开(公告)号：US20120229141A1

公开(公告)日：2012-09-13

申请号：US13407852

申请日：2012-02-29

申请人： Robert W. Brown ,  Yong Wu ,  Zhen Yao ,  Shmaryu Shvartsman ,  Thomas Chmielewski ,  Timothy Eagan

发明人： Robert W. Brown ,  Yong Wu ,  Zhen Yao ,  Shmaryu Shvartsman ,  Thomas Chmielewski ,  Timothy Eagan

IPC分类号： G01R33/422 ,  B26D5/00 ,  G06F17/50

CPC分类号： G01R33/422 ,  G01R33/341 ,  G01R33/385 ,  G01R33/4822 ,  G01R33/56518 ,  Y10T83/505

摘要： Radio frequency (RF) shields used with magnetic resonance imaging (MRI) apparatus may experience gradient field induced eddy currents and RF field induced eddy currents. These eddy currents can cause the RF shield to heat up at an undesirable rate. RF shields are designed to have a desired degree of RF shielding and a desired heating attribute. Design goals for RF shields include gradient field transparency and RF field opacity, both of which can be influenced by eddy currents. Example methods identify a gradient field that will induce eddy currents and identify an RF field that will induce eddy currents. If a region on the RF shield is identified where the desired heating attribute will not be achieved, then a pattern of axial cuts and azimuthal cuts can be made in the RF shield to reduce gradient eddy current heating in the RF shield while maintaining desired RF shielding.

摘要翻译： 与磁共振成像（MRI）装置一起使用的射频（RF）屏蔽可能会经历梯度场感应涡流和射频场感应涡流。 这些涡流可以使RF屏蔽以不期望的速率加热。 RF屏蔽被设计为具有期望的RF屏蔽程度和期望的加热属性。 RF屏蔽的设计目标包括梯度场透明度和RF场不透明度，这两者都可以受涡流影响。 示例性方法识别将引起涡流的梯度场，并识别将产生涡流的RF场。 如果RF屏蔽上的区域被识别出将不能实现所需的加热属性，则可以在RF屏蔽中进行轴向切割和方位切割的图案，以减少RF屏蔽中的梯度涡流加热，同时保持所需的RF屏蔽 。

公开(公告)号：US20060033497A1

公开(公告)日：2006-02-16

申请号：US10536334

申请日：2003-11-25

申请人： Thomas Chmielewski ,  James Flock ,  Timothy Eagan

发明人： Thomas Chmielewski ,  James Flock ,  Timothy Eagan

IPC分类号： G01V3/00

CPC分类号： G01R33/34046

摘要： A birdcage coil (16) used in conjunction with a magnetic resonance imaging apparatus includes a first conductive loop (81, 581), a second conductive loop (82, 582), and a plurality of first conductor rungs (80, 580) disposed between the first and second conductive loops. A third conductor (83, 83″, 583) is coupled to the second conductive loop at resonance frequencies, such as by second conductor rungs (84, 84″, 584). The birdcage coil also includes switches (590) for switching the birdcage coil at least among: 1) an RF transmit mode to operate as an RF transmit coil; and 2) an RF receive mode to operate as an RF receive coil.

摘要翻译： 与磁共振成像装置结合使用的鸟笼线圈（16）包括第一导电回路（81,581），第二导电回路（82,582）和多个第一导体梯级（80,580） 第一和第二导电回路。 第三导体（83,83“，583）以共振频率，例如通过第二导体梯级（84,84”，584）耦合到第二导电回路。 鸟笼线圈还包括用于至少在以下各项之间切换鸟笼线圈的开关（590）：1）RF发射模式以用作RF发射线圈; 和2）用作RF接收线圈的射频接收模式。

公开(公告)号：US5336988A

公开(公告)日：1994-08-09

申请号：US16042

申请日：1993-02-10

申请人： Thomas Chmielewski ,  David A. Molyneaux ,  William O. Braum

发明人： Thomas Chmielewski ,  David A. Molyneaux ,  William O. Braum

IPC分类号： G01R27/28 ,  G01R33/28 ,  G01R33/36 ,  G01R33/00

CPC分类号： G01R27/28 ,  G01R33/28 ,  G01R33/3628

摘要： An RF device (A) under test is connected with ports or jacks (14, 16) of an S-parameter test set (B). An RF input jack (18) is connected with an RF tracking signal output (20) of a spectrum analyzer (C) to receive an RF tracking signal. An output jack (22) is connected with a receiver input (24) of the spectrum analyzer. A mode control (30) internal to the test set is controlled by a programmable control sequence generator (34) of the spectrum analyzer. The mode control controls a switch array (32), preferably PIN diodes, which interconnect the RF input jack (18), the RF output jack (22), the two jacks (14, 16) that are connected to the device under test, and a 50 Ohm termination (54) in four modes to make reflection measurements and two transmission measurements. DC bias jacks (26, 28) are connected with a DC power for injecting a DC component into the RF signals applied to the device under test.

摘要翻译： 被测试的RF设备（A）与S参数测试仪（B）的端口或插座（14,16）连接。 RF输入插孔（18）与频谱分析仪（C）的RF跟踪信号输出（20）连接，以接收RF跟踪信号。 输出插孔（22）与频谱分析仪的接收器输入端（24）连接。 测试仪内部的模式控制（30）由频谱分析仪的可编程控制序列发生器（34）控制。 模式控制控制开关阵列（32），优选PIN二极管，其将RF输入插孔（18），RF输出插孔（22），连接到被测器件的两个插座（14,16） 和50欧姆终端（54），以进行反射测量和两次传输测量。 DC偏压千斤顶（26,28）与用于将DC分量注入施加到被测器件的RF信号的直流电源连接。

公开(公告)号：US07560934B1

公开(公告)日：2009-07-14

申请号：US12123020

申请日：2008-05-19

申请人： Thomas Chmielewski ,  Brian J. Cohen

发明人： Thomas Chmielewski ,  Brian J. Cohen

IPC分类号： G01V3/00

CPC分类号： G01R33/365 ,  G01R33/3621 ,  G01R33/3628 ,  G01R33/3685

摘要： An MRI system includes a receive coil having a coil element. Two preamplifiers are used in relation to the coil element, thus placing a large impedance in series with the coil element. The optimal noise impedance of each preamplifier is matched to that of the other preamplifier.

摘要翻译： MRI系统包括具有线圈元件的接收线圈。 相对于线圈元件使用两个前置放大器，因此与线圈元件串联放置大的阻抗。 每个前置放大器的最佳噪声阻抗与其他前置放大器的最佳噪声阻抗匹配。

公开(公告)号：US20090054759A1

公开(公告)日：2009-02-26

申请号：US11843744

申请日：2007-08-23

申请人： Thomas Chmielewski ,  Brian J. Cohen ,  Yiping Guan

发明人： Thomas Chmielewski ,  Brian J. Cohen ,  Yiping Guan

IPC分类号： A61B5/055

CPC分类号： G01R33/34046 ,  G01R33/34053 ,  G01R33/3415 ,  G01R33/365

摘要： The present invention relates to an element configuration within an RF coil for use for MRI. The invention provides for an inherently electromagnetically decoupled solenoid element pair for receiving radio frequency magnetic resonance signals within a vertical field MRI system. The elements of the solenoid element pair described herein are typically positioned in a coplanar, side-by-side position. The decoupling of the solenoid pair can be accomplished through numerous methods including but not limited to an overlapping between the elements of the solenoid pair, use of a capacitor shared between the elements of the solenoid pair, or the use of overlapped inductors between the elements of the solenoid pair.

摘要翻译： 本发明涉及用于MRI的RF线圈内的元件结构。 本发明提供了用于在垂直场MRI系统内接收射频磁共振信号的固有的电磁去耦螺线管元件对。 这里描述的螺线管元件对的元件通常位于共面的并排位置。 螺线管对的解耦可以通过多种方法来实现，包括但不限于螺线管对的元件之间的重叠，螺线管对元件之间共用的电容器的使用，或者使用重叠的电感器 螺线管对。

公开(公告)号：US07443163B2

公开(公告)日：2008-10-28

申请号：US11575151

申请日：2005-08-19

申请人： Marcel Warntjes ,  Marinus J. A. M. Van Helvoort ,  Steven M. Koenig ,  Thomas Chmielewski

发明人： Marcel Warntjes ,  Marinus J. A. M. Van Helvoort ,  Steven M. Koenig ,  Thomas Chmielewski

IPC分类号： G01V3/00

CPC分类号： G01R33/3657 ,  G01R33/34007 ,  G01R33/3628

摘要： A low profile radio frequency coil (32, 44, 441, 442, 443) for use in a magnetic resonance imaging system includes a low profile antenna (34, 102, 202, 302) that is configured to resonate at about a magnetic resonance frequency of the magnetic resonance imaging system. A generally planar inductor (110, 112, 210, 240, 310) is electrically connected or coupled with the low profile antenna. The generally planar inductor provides selected frequency filtering of a radio frequency signal received by or transmitted by the low profile antenna.

摘要翻译： 一种用于磁共振成像系统的低频无线电频率线圈（32,44,44个，44个，44个3）包括 配置为在磁共振成像系统的大约磁共振频率下谐振的低剖面天线（34,102,202,302）。 大体上平面的电感器（110,112,210,240,310）与薄型天线电连接或耦合。 通常平面的电感器提供由低轮廓天线接收或由低轮廓天线发送的射频信号的选择的频率滤波。