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公开(公告)号：US4839594A
公开(公告)日：1989-06-13
申请号：US120475
申请日：1987-11-13
CPC分类号： G01R33/3621 , G01R33/34046 , G01R33/341 , G01R33/3628
摘要： Magnet (12) creates a main magnetic field along a z-axis through an image region. A localized coil (D) is disposed in the image region at least to receive magnetic resonance signals from nuclei of the subject which have been induced to resonance. The localized coil includes an inner conductor (30), an outer conductor (32), and a dielectric material (52) therebetween. The outer conductor defines a gap (50) midway between its ends. One end of the inner conductor is connected with a gate of an FET transistor (66) and the outer conductor is connected with its source. The transistor source and drain are connected by a coaxial transmission cable (38) with a DC power supply (70) which provides a DC bias across the transistor source and drain. The cable also connects the transistor with a radio frequency receiver (40) to convey preamplified magnetic resonance signals thereto. The other end of the inner conductor may be connected with the outer conductor to provide an unbalanced localized coil or the ends may each be connected with an FET transistor (66a, 66 b) in a balanced coil arrangement (FIG. 9).
摘要翻译： 磁体（12）通过图像区域沿z轴产生主磁场。 至少在图像区域中设置局部线圈（D）以接收已经被诱导到共振的受试者的核的磁共振信号。 局部线圈包括内部导体（30），外部导体（32）和介电材料（52）。 外导体在其端部之间的中间限定间隙（50）。 内部导体的一端与FET晶体管（66）的栅极连接，外部导体与其源极连接。 晶体管源极和漏极由具有直流电源（70）的同轴传输电缆（38）连接，直流电源（70）在晶体管源极和漏极之间提供直流偏置。 电缆还将晶体管与射频接收器（40）连接，以将预放大的磁共振信号传送到其上。 内部导体的另一端可以与外部导体连接以提供不平衡的局部线圈，或者各个端子可以以平衡线圈装置（图9）与FET晶体管（66a，66b）连接。
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公开(公告)号：US4879516A
公开(公告)日：1989-11-07
申请号：US199202
申请日：1988-05-26
IPC分类号： G01R33/34 , G01R33/341 , G01R33/36
CPC分类号： G01R33/3678 , G01R33/34046 , G01R33/341 , G01R33/3628
摘要： A magnetic resonance imager includes a quadrature coil assembly (20) for transmitting radio frequency signals into and receiving magnetic resonance signal from an examination region. The quadrature coils assembly includes a first coil (22) and a second coil (24). A shunt path (32, 64, 74, 84, 94, 98, 100, 112, 114, 122) provides a current path by shunting at least a portion of one of the coils. A variable impedance (34, 66, 76, 86, 96, 110, 120) adjusts the amount of current flow through the shunt path and the current flow through the bypassed coil portion. More specifically, adjusting the impedance changes the magnetization vector generated by the coil assembly in a transmit mode and adjusts their relative isolation in a receive mode. The quadrature coils are mounted such that they are offset by about, but not quite, 90.degree.. The variable impedance is adjusted until the offset is brought precisely to 90.degree.. In this manner, the quadrature coils are adjusted electronically after assembly to insure the precision of their isolation.
摘要翻译： 磁共振成像器包括：正交线圈组件（20），用于将射频信号传送到检测区域并接收来自检查区域的磁共振信号。 正交线圈组件包括第一线圈（22）和第二线圈（24）。 分路（32,64,74,84,94,98,100,112,114,122）通过分流线圈中的一个的至少一部分来提供电流路径。 可变阻抗（34,66,76,86,96,110,120）调节通过分流路径的电流量和通过旁路线圈部分的电流。 更具体地，调整阻抗以发射模式改变由线圈组件产生的磁化矢量并且在接收模式中调整它们的相对隔离度。 正交线圈被安装成使得它们被偏移约90度，但不完全偏移90度。 调整可变阻抗，直到偏移精确到90度。 以这种方式，组装之后电子调整正交线圈以确保其隔离的精度。
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公开(公告)号：US4841248A
公开(公告)日：1989-06-20
申请号：US86277
申请日：1987-08-17
IPC分类号： G01R33/34 , G01R33/341 , G01R33/36
CPC分类号： G01R33/34046 , G01R33/341 , G01R33/36 , G01R33/3628
摘要： Magnets (12) create a main magnetic field along a z-axis through an image region. A localized coil (D) is disposed in the image region at least to receive magnetic resonance signals from nuclei of the subject which have been induced to resonance. The localized coil includes an inner conductor (30), preferably a plate, which defines a current path extending along the z-axis. The inner conductor is mounted closely adjacent and parallel to a surface of the subject. An outer conductor (32), preferably also a plate, is mounted parallel to but further from the subject than the first conductor. A connecting member (34) interconnects a first end of the inner and outer conductors and is disposed perpendicular to the z-axis. A matching circuit (36) including capacitors (50) which define the resonant frequency of the coil are connected adjacent second ends of the inner and outer conductors. Because the nuclei induced to resonance within the z-axis magnetic field generate magnetic resonance components in the x-y plane, an optimal coupling is achieved to reception of the magnetic resonance signals.
摘要翻译： 磁体（12）通过图像区域沿z轴产生主磁场。 至少在图像区域中设置局部线圈（D）以接收已经被诱导到共振的受试者的核的磁共振信号。 局部线圈包括限定沿z轴延伸的电流路径的内导体（优选为板）。 内部导体紧密地安装在主体表面上并平行。 外导体（32），优选地也是板，与第一导体平行但是远离被检体安装。 连接构件（34）将内导体和外导体的第一端互连并且垂直于z轴布置。 包括限定线圈的谐振频率的电容器（50）的匹配电路（36）被连接在内导体和外导体的第二端附近。 因为在z轴磁场内引起谐振的核在x-y平面中产生磁共振分量，所以实现了接收磁共振信号的最佳耦合。
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公开(公告)号：US4797617A
公开(公告)日：1989-01-10
申请号：US933152
申请日：1986-11-21
申请人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
发明人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
CPC分类号： G01R33/34046 , G01R33/34007 , G01R33/3628 , G01R33/3657
摘要： A nuclear magnetic resonance radio frequency coil. The disclosed coil provides high frequency resonance signals for perturbing a magnetic field within the coil. The coil is impedance matched and tuned with adjustable capacitors. A balanced configuration is achieved with a co-axial cable chosen to phase shift an energization signal coupled to the coil. The preferred coil is a thin metallic foil having a shorting conductor, four wing conductors, and uniquely shaped parallel cross conductors connecting the shorting and wing conductors. When mounted to an rf transmissive plastic substrate and energized the coil produces a homogenous field within a region of interest the size of a patient head. A semicircular balanced feedbar arrangement is used to minimize undesired field contributions.
摘要翻译： 核磁共振射频线圈。 所公开的线圈提供用于扰乱线圈内的磁场的高频谐振信号。 线圈阻抗匹配并用可调电容器调谐。 使用同轴电缆实现平衡配置，以使相耦合到线圈的通电信号相移。 优选的线圈是具有短路导体，四个机翼导体和连接短路和翼导体的独特成形的平行十字导体的薄金属箔。 当安装到rf透射塑料基板并通电时，线圈在患者头部的尺寸的感兴趣区域内产生均匀的场。 使用半圆平衡馈线布置来最小化不期望的场贡献。
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公开(公告)号：US4793356A
公开(公告)日：1988-12-27
申请号：US765708
申请日：1985-08-14
IPC分类号： A61B5/055 , A61B10/00 , G01R33/341 , G01R33/36 , G01R33/44 , G01R33/48 , H01F6/06 , A61B5/05
CPC分类号： G01R33/3628 , G01R33/341
摘要： A resonance exciting coil (C) excites magnetic resonance in nuclei disposed in an image region in which a main magnetic field and transverse gradients have been produced. A flexible receiving coil (D) includes a flexible plastic sheet (40) on which one or more loops (20) are adhered to receive signals from the resonating nuclei. Velcro straps (46) strap the flexible sheet and the attached coil into close conformity with the surface of the portion of the patient to be imaged. An impedance matching or coil resonant frequency adjusting network (50) is mounted on the flexible sheet for selectively adjusting at least one of an impedance match and the peak sensitivity resonant frequency of the receiving coil. A preamplifier (52) amplifies the received signals prior to transmission on a cable (24). A selectively variable voltage source (70) applies a selectively adjustable DC bias voltage to the cable for selectively adjusting at least one of the impedance match and the LC resonant frequency of the receiving coil. The received signals are amplified by an amplifier (82) and processed by an image processor (30) to form man-readable images of the examined region of the patient for display on a video display (32) or the like.
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公开(公告)号：US4634980A
公开(公告)日：1987-01-06
申请号：US641570
申请日：1984-08-16
申请人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
发明人： George J. Misic , Aarne Lillo , John L. Patrick , G. Neil Holland
CPC分类号： G01R33/34007 , G01R33/34046 , G01R33/3628 , G01R33/3657
摘要： A nuclear magnetic resonance radio frequency coil. The disclosed coil provides high frequency resonance signals for perturbing a magnetic field within the coil. The coil is impedance matched and tuned with adjustable capacitors. A balanced configuration is achieved with a co-axial cable chosen to phase shift an energization signal coupled to the coil. The preferred coil is a thin metallic foil having a shorting conductor, four wing conductors, and uniquely shaped parallel cross conductors connecting the shorting and wing conductors. When mounted to a rf transmissive plastic substrate and energized the coil produces a homogeneous field within a region of interest the size of a patient head. A semicircular balanced feedbar arrangement is used to minimize undesired field contributions.
摘要翻译： 核磁共振射频线圈。 所公开的线圈提供用于扰乱线圈内的磁场的高频谐振信号。 线圈阻抗匹配并用可调电容器调谐。 使用同轴电缆实现平衡配置，以使相耦合到线圈的通电信号相移。 优选的线圈是具有短路导体，四个机翼导体和连接短路和翼导体的独特成形的平行十字导体的薄金属箔。 当安装到rf透射塑料基板并通电时，线圈在患者头部的尺寸的感兴趣区域内产生均匀的场。 使用半圆平衡馈线布置来最小化不期望的场贡献。
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公开(公告)号：US4920318A
公开(公告)日：1990-04-24
申请号：US252819
申请日：1988-10-03
IPC分类号： G01R33/34 , G01R33/341 , G01R33/36
CPC分类号： G01R33/3628 , G01R33/34046 , G01R33/341 , G01R33/34007 , G01R33/34084 , G01R33/3657
摘要： A resonance exciting coil (C) excites magnetic resonance in nuclei disposed in an image region in which a main magnetic field and transverse gradients have been produced. A flexible receiving coil (D) includes a flexible plastic sheet (40) on which one or more loops (20) are adhered to receive signals from the resonating nuclei. Velcro straps (46) strap the flexible sheet and the attached coil into close conformity with the surface of the portion of the patient to be imaged. An impedance matching or coil resonant frequency adjusting network (50) is mounted on the flexible sheet for selectively adjusting at least one of an impedance match and the peak sensitivity resonant frequency of the receiving coil. A preamplifier (52) amplifies the received signals prior to transmission on a cable (24). A selectively variable voltage source (70) applies a selectively adjustable DC bias voltage to the cable for selectively adjusting at least one of the impedance match and the LC resonant frequency of the receiving coil. The received signals are amplified by an amplifier (82) and processed by an image processor (30) to form man-readable images of the examined region of the patient for display on a video display (32) or the like.
摘要翻译： 共振励磁线圈（C）在设置在已经产生主磁场和横向梯度的图像区域中的核中激发磁共振。 柔性接收线圈（D）包括柔性塑料片（40），一个或多个环（20）粘附在柔性塑料片上以接收来自谐振核的信号。 魔术贴带（46）将柔性片材和附接的线圈绑定成与待成像的患者部分的表面紧密一致。 阻抗匹配或线圈共振频率调整网络（50）安装在柔性片上，用于选择性地调节接收线圈的阻抗匹配和峰值灵敏度谐振频率中的至少一个。 前置放大器（52）在电缆（24）上传输之前放大所接收的信号。 选择性可变电压源（70）向电缆施加选择性可调节的直流偏置电压，用于选择性地调节接收线圈的阻抗匹配和LC谐振频率中的至少一个。 所接收的信号由放大器（82）放大并由图像处理器（30）处理，以形成用于在视频显示器（32）等上显示的被检查区域的人可读图像。
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8.发明授权
公开(公告)号：US4731584A
公开(公告)日：1988-03-15
申请号：US897046
申请日：1986-08-14
申请人： George J. Misic , John L. Patrick
发明人： George J. Misic , John L. Patrick
IPC分类号： G01N33/00 , G01R33/34 , G01R33/341 , G01R33/36 , G01R33/20
CPC分类号： G01R33/3628 , G01R33/34046 , G01R33/341
摘要： A magnetic field control (A) causes a magnetic field through an imaging region of a magnetic resonance spectrometer. A radio frequency generator (20) generates radio frequency signals which are transmitted on a transmission line (22) to a probe coil (C). Magnetic resonance signals received by the probe coil (C) are conveyed over the transmission line to a radio frequency receiver (24) for reconstruction into a magnetic resonance image. An inductive matching network (D) is connected between the probe coil and the transmission line for matching the resistive impedance of the coil with the resistive impedance of the transmission line and for resonating the coil at a frequency other than its self resonance frequency. When the probe coil is operated above the self resonance frequency, it is capacitively reactive. An inductor (40) is connected across coil feed points (30, 32) of the probe coil. The inductive reactance of the matching inductor is selected such that the capacitive reactance of the probe coil at a selected frequency above the self resonance frequency is cancelled.
摘要翻译： 磁场控制（A）通过磁共振光谱仪的成像区域产生磁场。 射频发生器（20）产生在传输线（22）上传输到探针线圈（C）的射频信号。 由探针线圈（C）接收的磁共振信号通过传输线传送到射频接收器（24），用于重建成磁共振图像。 感应匹配网络（D）连接在探针线圈和传输线之间，用于将线圈的电阻阻抗与传输线的阻抗阻抗匹配，并且以不同于其自谐振频率的频率谐振线圈。 当探头线圈工作在自谐振频率以上时，电容性反应。 电感器（40）连接在探针线圈的线圈馈电点（30,32）之间。 选择匹配电感器的感抗，使得探针线圈在高于自谐振频率的选定频率处的电容电抗被消除。
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公开(公告)号：US4740751A
公开(公告)日：1988-04-26
申请号：US894313
申请日：1986-08-07
申请人： George J. Misic , John L. Patrick
发明人： George J. Misic , John L. Patrick
CPC分类号： G01R33/34069 , G01R33/343 , G01R33/3628 , G01R33/34007 , G01R33/341
摘要： A resonator coil assembly (32) includes a dielectric sleeve (40) on which a first resonator coil portion (42) and a second resonator coil portion (44), each of copper foil, are adhered. The dielectric sleeve is dimensioned to receive a human torso therein and in one embodiment (FIG. 1) is circular in cross section and in another (FIG. 4) is elliptical in cross section. A pair of adjustable tuning capacitances (64, 66) and a pair of adjustable matching capacitances (68, 70) are interconnected between one end of the each coil portion and a metal bore liner (54). An opposite end of the coil portions are capacitively coupled to each other (FIG. 1) or to the bore liner (FIG. 3). A half wave length cable (72) interconnects the junctions between the first and second tuning and matching capacitances. One of these junctions is connected by a cable (74) with a radio frequency generator (30) and a radio receiver (34).
摘要翻译： 谐振器线圈组件（32）包括电介质套筒（40），其上粘附有每个铜箔的第一谐振器线圈部分（42）和第二谐振器线圈部分（44）。 电介质套筒的尺寸被设计成在其中容纳人体躯干，在一个实施例中（图1）的横截面是圆形的，而另一个（图4）的横截面是椭圆形的。 一对可调节调谐电容（64,66）和一对可调整的匹配电容（68,70）在每个线圈部分的一端和金属内衬（54）之间互连。 线圈部分的相对端部彼此电容耦合（图1）或孔径衬套（图3）。 半波长电缆（72）互连第一和第二调谐和匹配电容之间的结。 这些连接点中的一个通过具有射频发生器（30）的电缆（74）和无线电接收器（34）连接。
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公开(公告)号：US08581590B2
公开(公告)日：2013-11-12
申请号：US13128361
申请日：2009-11-12
IPC分类号： G01V3/00
CPC分类号： G01R33/341 , G01R33/34084 , G01R33/3678
摘要： An intracavity probe for use with an MR system allows images and spectra of internal anatomical structures to be obtained. The intracavity probe houses within its balloon-type enclosure a single-element quadrature coil sensitive to both the vertical and horizontal components of the MR signal. The quadrature coil by means of its output line is designed to plug into a dedicated interface device with which to interface the quadrature coil with the MR system. Drive capacitors within the coil in conjunction with the electrical length of the output line and phase shifting networks within the interface device enable complete decoupling of the quadrature coil from the transmit fields generated by the MR system. Preamplifier, power splitting and combining networks within the interface device process voltage signals representative of the horizontal and vertical components of the MR signal and enable them to be conveyed to the input port(s) of the MR system.
摘要翻译： 用于MR系统的腔内探针允许获得内部解剖结构的图像和光谱。 腔内探头在其气球型外壳内容纳有对MR信号的垂直和水平分量敏感的单元正交线圈。 通过其输出线的正交线圈被设计成插入专用接口装置中，以使正交线圈与MR系统接口。 线圈内的驱动电容与输出线的电气长度以及接口装置内的相移网络之间能够使正交线圈与由MR系统产生的发射场完全解耦。 接口设备内的前置放大器，功率分配和组合网络处理代表MR信号的水平和垂直分量的电压信号，并使其能够被传送到MR系统的输入端口。
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