Digital combination and correction of quadrature magnetic resonance
receiver coils
    1.
    发明授权
    Digital combination and correction of quadrature magnetic resonance receiver coils 失效
    正交磁共振接收线圈的数字组合和校正

    公开(公告)号:US5510711A

    公开(公告)日:1996-04-23

    申请号:US286758

    申请日:1994-08-05

    CPC分类号: G01R33/3678 G01R33/5659

    摘要: Magnetic resonance is excited in selected portions of a subject disposed within a temporally uniform magnetic field of a magnetic resonance imaging system. A quadrature coil assembly (30) receives radio frequency magnetic resonance signals from the subject. Commonly, the quadrature coil fails to receive signals in true quadrature over the entire examination region. Resonance signals from a first coil (32) and a second, orthogonal coil (34) are received (40, 42), digitized (44, 46), and Fourier transformed (50, 52) into complex images. Each complex image includes an array or grid of vector data values having a magnitude and a direction or phase angle. If the quadrature coil was truly quadrature over the entire region of interest, the data values of both complex images would be a unit vectors. The vector of one image would be offset by 90.degree. from the vectors of the other. A phase correction board (54) sets the phase angle of the corresponding data values of the first and second complex images to a common vector direction or phase angle. A magnitude correction board (56) adjusts the magnitude of each corresponding data value of the first and second complex images. The phase angle and magnitude corrected complex data images are summed (58) and the real or magnitude image is stored in an image memory (62).

    摘要翻译: 在设置在磁共振成像系统的时间均匀磁场内的被摄体的选定部分激发磁共振。 正交线圈组件(30)从主体接收射频磁共振信号。 通常,正交线圈不能在整个检查区域接收真正正交信号。 来自第一线圈(32)和第二正交线圈(34)的共振信号被接收(40,42),数字化(44,46)和傅里叶变换(50,52)成复数图像。 每个复合图像包括具有幅度和方向或相位角的矢量数据值的阵列或网格。 如果正交线圈在感兴趣的整个区域上是真正的正交的,则两个复数图像的数据值将是单位向量。 一个图像的向量将从另一个图像的向量偏移90°。 相位校正板(54)将第一和第二复合图像的相应数据值的相位角设置为公共矢量方向或相位角。 幅度校正板(56)调整第一和第二复合图像的每个相应数据值的大小。 将相位角和幅度校正的复数数据图像求和(58),并将实际或幅度图像存储在图像存储器(62)中。

    Method and apparatus for ferrous object and/or magnetic field detection for MRI safety
    2.
    发明授权
    Method and apparatus for ferrous object and/or magnetic field detection for MRI safety 失效
    用于铁质物体和/或磁场检测用于MRI安全的方法和装置

    公开(公告)号:US07696751B2

    公开(公告)日:2010-04-13

    申请号:US11635417

    申请日:2006-12-07

    IPC分类号: G01V3/00

    CPC分类号: G01R33/288

    摘要: A method and apparatus for ferrous object and/or magnetic field detection are provided. Embodiments can improve magnetic resonance imaging (MRI) safety and increase the safety of MRI facilities. Embodiments can detect a given magnetic field strength around a MRI machine and alert users to the field's presence. In an embodiment, the magnetic field warning system can rely on a single badge that warns its user. In another embodiment, the badge can utilize an RFID system. The RFID system can turn the badge on when it enters the MRI room and off when it leaves the MRI room. In another embodiment, a badge with a rechargeable battery and charger can be utilized with or without an RFID tag. The subject badges or other detection devices can be worn by a person, located on or near a ferrous object, embedded in clothing, or located in other positions convenient to a user.

    摘要翻译: 提供了一种用于铁物体和/或磁场检测的方法和装置。 实施例可以改善磁共振成像(MRI)的安全性并增加MRI设备的安全性。 实施例可以检测MRI机器周围的给定磁场强度,并且向用户提醒现场的存在。 在一个实施例中,磁场警告系统可以依靠警告其用户的单个徽章。 在另一个实施例中,徽章可以利用RFID系统。 当RFID系统进入MRI室时,RFID系统可以打开徽章,当离开MRI室时,它将被关闭。 在另一个实施例中,具有可充电电池和充电器的徽章可以在有或没有RFID标签的情况下使用。 主体徽章或其他检测装置可以由位于或接近有色金属物体的人佩戴,嵌入衣服中,或位于便于使用者的其他位置。

    Quadrature surface coils for magnetic resonance imaging
    3.
    发明授权
    Quadrature surface coils for magnetic resonance imaging 失效
    用于磁共振成像的正交表面线圈

    公开(公告)号:US4918388A

    公开(公告)日:1990-04-17

    申请号:US234278

    申请日:1988-08-19

    摘要: A thin dielectric sheet (36) has a first or loop coil (30) defined on one surface thereof and a second or Helmholtz coil (32) defined on an obverse surface thereof. The dielectric sheet and associated coils may be laid flat (FIG. 3) or bent to match a selected curved surface of the subject (FIGS. 6-8). The first and second coils are arranged symmetrically about an axis or plane of symmetry (34). The first coil has an associated magnetic field along a y-axis and the second coil has an associated magnetic field along the x-axis. Circuits (40 and (42) tune the first and second magnetic resonance coils to a preselected magnetic resonance frequency. Magnetic resonance signals of the selected frequency received by one of the coils are phase shifted 90.degree. by a phase shifting circuit (50) and combined with the unphase shifted signals from the other coil by a combining circuit (52). The combined signals are amplified (54) and conveyed to electronic image processing circuitry (E) of a magnetic resonance scanner.

    摘要翻译: 薄介电片(36)具有限定在其一个表面上的第一或环形线圈(30)和限定在其正面上的第二或亥姆霍兹线圈(32)。 电介质片和相关联的线圈可以平放(图3)或弯曲以匹配被摄体的选定曲面(图6-8)。 第一和第二线圈围绕对称轴(34)对称地布置。 第一线圈具有沿着y轴的相关磁场,而第二线圈具有沿x轴的相关磁场。 电路(40和(42)将第一和第二磁共振线圈调谐到预选的磁共振频率,由一个线圈接收的所选频率的磁共振信号由相移电路(50)相移90°并组合 通过组合电路(52)将来自另一个线圈的相位移动信号放大(54)并传送到磁共振扫描器的电子图像处理电路(E)。

    Vertical field quadrature phased array coil system
    5.
    发明授权
    Vertical field quadrature phased array coil system 失效
    垂直场正交相控阵线圈系统

    公开(公告)号:US5578925A

    公开(公告)日:1996-11-26

    申请号:US512274

    申请日:1995-08-18

    摘要: A vertical B.sub.0 temporally constant magnetic field is defined between a pair of pole faces (12, 14) that are interconnected by a C-shaped ferrous magnetic flux path (16). A quadrature radio frequency coil array (50) is disposed in a plane orthogonal to the B.sub.0 field. The coil array includes a plurality of coils (50.sub.1, 50.sub.2, . . . ) that are disposed in a partially overlapping relationship. Each of the coils has a peripheral loop (60), preferably defined by four linear legs (60.sub.1, 60.sub.2, 60.sub.3, 60.sub.4) of equal length which define a square. A pair of crossing elements (62.sub.1, 62.sub.2) are connected with mid-points of opposite sides of the square, the opposite mid-points are 180.degree. out-of-phase with each other at the magnetic resonance frequency and 90.degree. out-of-phase with neighboring mid-points of the square. The crossing elements cross but are not connected, in a symmetric relationship. Each of the crossing elements has a radio frequency pick-up (64.sub.1, 64.sub.2) associated therewith. The two radio frequency pick-ups receive 90.degree. offset, quadrature radio frequency signals from resonating nuclei within the B.sub.0 field.

    摘要翻译: 垂直B0时间常数磁场被限定在由C形铁磁通路(16)互连的一对极面(12,14)之间。 正交射频线圈阵列(50)设置在与B0场正交的平面中。 线圈阵列包括以部分重叠关系设置的多个线圈(501,502 ...)。 每个线圈具有外围环路(60),优选地由四个线性支线(601,602,603,604)限定平行的相等长度。 一对交叉元件(621,622)与正方形的相对侧的中点连接,相反的中点在磁共振频率处彼此相差180度,在90度以外 与广场的相邻中点相邻。 交叉元素交叉但不是以对称关系连接。 每个交叉元件具有与其相关联的射频拾取器(641,642)。 两个射频拾取器从B0场内的谐振核接收90°偏移,正交射频信号。

    Scalar S-parameter test set for NMR instrumentation measurements
    6.
    发明授权
    Scalar S-parameter test set for NMR instrumentation measurements 失效
    用于NMR仪器测量的Scalar S参数测试仪

    公开(公告)号:US5336988A

    公开(公告)日:1994-08-09

    申请号:US16042

    申请日:1993-02-10

    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。

    Computer controlled switching of multiple RF coils
    7.
    发明授权
    Computer controlled switching of multiple RF coils 失效
    多个射频线圈的计算机控制切换

    公开(公告)号:US5138260A

    公开(公告)日:1992-08-11

    申请号:US616890

    申请日:1990-11-21

    CPC分类号: G01R33/3415 G01R33/54

    摘要: A whole body RF antenna (22) surrounds an examination region (14). A localized coil array (40) having a plurality of coils (42a, 43b, . . . ) is mounted in the examination region. A switch array (48) selectively connects a selected one of the coils with an output (46). In a pilot or alignment scan, an imaging sequence is conducted using the whole body antenna (22) to generate an image of a portion of the surface coil array and the patient in the examination region. The coil array includes a marker (82) that is readily identifiable in the resultant image displayed on a video monitor (36). The location of slices for more detailed imaging are selected by positioning a cursor (64) on the video display. The position or coordinate system of the selected slices is aligned with the position or coordinate system of the coil array by positioning the cursor over the image of the marker and noting its position. Properties or parameters of each coil of the array are stored in a look up table (74). The parameters of each selected slice and imaging sequence are compared (72) with the properties in the look up table in order to determine an optimal one or more of the coils (42) for use in each imaging sequence. An imaging sequence along each of the slices is conducted utilizing the corresponding selected coils.

    MR compatible neurosurgical positioning apparatus
    8.
    发明授权
    MR compatible neurosurgical positioning apparatus 有权
    MR兼容神经外科定位装置

    公开(公告)号:US6079681A

    公开(公告)日:2000-06-27

    申请号:US157347

    申请日:1998-09-18

    摘要: An apparatus (1) for supporting a surgical instrument in the operative environment of an imaging device comprises components all made of a material compatible for use in the operative environment of the imaging device. The components of the apparatus (1), made of such a material, include a member (32) that has a spherical surface and includes a bore (50) extending through the member along its diameter. A grip (26) has a grip surface (40) defining an aperture that is adapted to receive the member for rotatable movement within the aperture. The grip (26) extends around the member (32) in a circumferential path and has a gap (42) therein. A fastener (30) is operatively connected to the grip (26). The fastener (30) is adjustable to change the size of the gap (42) and adjust the compressive force applied to the received member (32) in the grip.

    摘要翻译: 用于在成像装置的操作环境中支撑外科器械的装置(1)包括全部由与成像装置的操作环境中兼容的材料制成的部件。 由这种材料制成的装置(1)的部件包括具有球形表面并包括沿其直径延伸穿过构件的孔(50)的构件(32)。 手柄(26)具有限定孔的抓握表面(40),所述孔适于容纳所述构件以在孔内旋转运动。 把手(26)在圆周路径中围绕构件(32)延伸并且在其中具有间隙(42)。 紧固件(30)可操作地连接到把手(26)。 紧固件(30)可调节以改变间隙(42)的尺寸并且调节施加到手柄中的接收构件(32)的压缩力。

    MRI endocavitary coils and decontamination
    9.
    发明授权
    MRI endocavitary coils and decontamination 失效
    MRI内脏线圈和去污

    公开(公告)号:US6051974A

    公开(公告)日:2000-04-18

    申请号:US979053

    申请日:1997-11-26

    CPC分类号: G01R33/285

    摘要: An endocavity RF coil assembly for an MRI apparatus includes a reusable probe (30). The reusable probe has a hollow outer cover (60) having a closed distal end and (62) an open proximate end (64). The distal end (62) is formed to fit into a cavity of a subject being examined. An active RF coil element (72) is rigidly formed about an internal sleeve (70) which is located within the distal end (62) of the outer cover (60). A tuning and matching circuit is disposed within the outer cover (60) on the proximate end (64) side of the active RF coil element (72). The tuning and matching circuit is arranged on a printed circuit board (74) and attached to the active RF coil element (72). An over-molded form (90) is connected to the proximate end (64) of the outer cover (60). The over-molded form (90) is arranged such that it seals the proximate end (64) of the outer cover (60) closed.

    摘要翻译: 用于MRI装置的内腔RF线圈组件包括可重复使用的探针(30)。 可重复使用的探针具有中空的外盖(60),其具有封闭的远端和(62)敞开的近端(64)。 远端(62)形成为适合被检查对象的空腔。 主动RF线圈元件(72)围绕位于外盖(60)的远端(62)内部的内套筒(70)而刚性地形成。 调谐和匹配电路设置在有源RF线圈元件(72)的近端(64)侧上的外盖(60)内。 调谐和匹配电路布置在印刷电路板(74)上,并连接到有源RF线圈元件(72)。 外模(90)连接到外盖(60)的近端(64)。 整体模制形式(90)被布置成使得其封闭外盖(60)的近端(64)。

    Temperature sensing and control system for cardiac monitoring electrodes
    10.
    发明授权
    Temperature sensing and control system for cardiac monitoring electrodes 失效
    心脏监测电极温度感应和控制系统

    公开(公告)号:US5209233A

    公开(公告)日:1993-05-11

    申请号:US653628

    申请日:1991-02-11

    摘要: A cardiac electrode (40) has a plug (48) which is frictionally received in a socket (50) of an electrical lead (56). An impedance (54) is connected in series between the electrical lead and the socket to pass ECG signals substantially unattenuated and for blocking radio frequency signals induced in the lead from reaching the socket and the electrode and heating the electrode to a sufficient temperature to burn the patient. The impedance includes an LC circuit (66, 68) which freely passes low frequency signals, such as cardiac signals, but which is tuned to resonance at radio frequencies, particularly at the frequency of resonance excitation and manipulation pulses of a magnetic resonance imager (A). Alternately, the impedance may include a resistive element for blocking the induced currents. A temperature sensor (60) is mounted in intimate contact with an electrically and thermally conductive socket portion (52) to sense the temperature of the electrode, indirectly. A temperature sensor lead (62), the cardiac lead (56), and a respiratory or other anatomical condition sensor are connected with a multiplexing means (140) which cyclically connects the output signals thereof with an analog to digital converter (142). The digital signals are converted to digital optical signals (102) to be conveyed along a light path (104) out of the examination region. The bits of the received digital signal are sorted (144) between an R-wave detector (120), a temperature limit check (122) which checks whether the temperature of the electrode exceeds preselected limits, and a respiratory detector (132).

    摘要翻译: 心电极(40)具有摩擦地容纳在电引线(56)的插座(50)中的插头(48)。 阻抗(54)串联连接在电引线和插座之间以使ECG信号基本上不衰减,并阻止在引线中感应的射频信号到达插座和电极,并将电极加热到足够的温度以烧毁 患者。 该阻抗包括一个LC电路(66,68),它可以自由地通过诸如心脏信号的低频信号,但被调谐到无线电频率的共振,特别是在磁共振成像器(A)的共振激励和操纵脉冲的频率 )。 或者,阻抗可以包括用于阻挡感应电流的电阻元件。 温度传感器(60)安装成与导电和导热插座部分(52)紧密接触以间接地感测电极的温度。 温度传感器引线(62),心脏引线(56)以及呼吸或其他解剖条件传感器与将其输出信号与模数转换器(142)循环连接的多路复用装置(140)连接。 数字信号被转换成数字光信号(102),沿着光路(104)输送出检查区域。 所接收的数字信号的比特在R波检测器(120),检查电极的温度是否超过预定极限的温度极限检查(122)和呼吸检测器(132)之间进行排序(144)。