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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：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：US4752738A
公开(公告)日：1988-06-21
申请号：US931726
申请日：1986-11-17
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： The magnetic resonance signals in a magnetic resonance imaging apparatus are detected by a surface or localized coil assembly (D). To improve the field homogeneity and increase the signal-to-noise ratio when examining a region of interest deep within a subject, the surface coil assembly is configured with a first coil portion (22) and a second coil portion (24). The first coil portion is disposed along an exterior surface of the subject. The second coil portion is disposed parallel to the first coil portion and displaced outward a distance (44) from the first coil portion and the subject exterior surface. The first and second coil portions are electrically interconnected with an opposite current phase in a dipole pair such that the second current portion reduces the sensitivity of the first coil portion to magnetic resonance signals originating close to the surface of the subject.
摘要翻译： 磁共振成像装置中的磁共振信号由表面或局部线圈组件（D）检测。 为了在检查受试者深处感兴趣的区域时改善场均匀性并增加信噪比，表面线圈组件配置有第一线圈部分（22）和第二线圈部分（24）。 第一线圈部分沿被检体的外表面设置。 第二线圈部分平行于第一线圈部分设置并向外移动与第一线圈部分和被摄体外表面的距离（44）。 第一和第二线圈部分与偶极对中的相反电流相电互连，使得第二电流部分将第一线圈部分的灵敏度降低到靠近被摄体表面的磁共振信号。
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7.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：US4780675A
公开(公告)日：1988-10-25
申请号：US85956
申请日：1987-08-14
CPC分类号： G01R33/561
摘要： An incomplete set of magnetic resonance image data is collected and stored in a view memory (40). The incomplete set of image data includes a central or first set of data values (42, 42') and a side or second set of data values (44, 44'). The central data set is operated on by a roll-off filter (64) and a Fourier transform (66) to create a normalized phase map (72). The first and second data sets are Fourier transformed (82) and phase corrected (86) by being multiplied with a complex conjugate (88) of the corresponding phase map data value. A third data set (46, 46') is generated (90) by determining the complex conjugate of the second or side data set. The third data set is Fourier transformed (94) and multiplied (98) by a corresponding value from the phase map to produce a second phase corrected image representation. The first and second phase corrected image representations are summed (100) and stored in a resultant image memory (102).
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公开(公告)号：US4912413A
公开(公告)日：1990-03-27
申请号：US260402
申请日：1988-10-20
IPC分类号： G01R33/54 , G01R33/561 , G01R33/565
CPC分类号： G01R33/54 , G01R33/561 , G01R33/565
摘要： An incomplete set of magnetic resonance image data is collected and stored in a view memory (40). The incomplete set of image data includes a central or first set of data values (42, 42') and half of the remaining data values (44, 44'). A symmetric data set which fills the other remaining half (46, 46') of the data values is generated (90) by determining the complex conjugate of each value of the incomplete data set. The incomplete and symmetric data sets are Fourier transformed (64, 94) to create first and second images f.sub.1 (x,y) and f.sub.2 (x,y). The first and second images are multiplied (100, 104) by conjugately symmetric phase correction values e.sup.i.phi.(x,y) and e.sup.-i.phi.(x,y) from a phase correction memory (70) to produce phase corrected images. The first and second phase corrected image representations are summed (110) and displayed (114). The phase correction values .phi.(x,y) may be derived (68) from the first image or from a phase image (86) derived (80, 82, 84) from a central or other portion of the acquired incomplete image data set.
摘要翻译： 一组不完整的磁共振图像数据被收集并存储在视图存储器（40）中。 不完整的图像数据集合包括中央或第一组数据值（42,42'）和剩余数据值（44,44'）的一半。 通过确定不完整数据集的每个值的复共轭来生成（90）填充数据值的另一半（46,46'）的对称数据集。 不完全和对称的数据集被傅里叶变换（64,94）以产生第一和第二图像f1（x，y）和f2（x，y）。 第一和第二图像通过来自相位校正存储器（70）的共对称相位校正值ei phi（x，y）和e-i phi（x，y）相乘（100,104）以产生相位校正图像。 将第一和第二相位校正图像表示相加（110）并显示（114）。 相位校正值phi（x，y）可以从第一图像或从所获取的不完整图像数据集合的中心部分或其他部分导出（80,82,84）的相位图像（86）导出（68）。
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