公开(公告)号：US4680548A

公开(公告)日：1987-07-14

申请号：US884674

申请日：1986-07-16

申请人： William A. Edelstein ,  John F. Schenck ,  Otward M. Mueller ,  Cecil E. Hayes

发明人： William A. Edelstein ,  John F. Schenck ,  Otward M. Mueller ,  Cecil E. Hayes

IPC分类号： G01N33/00 ,  G01R33/34 ,  G01R33/36 ,  G01R33/20

CPC分类号： G01R33/3628 ,  G01R33/34076

摘要： In one embodiment, referred to as the "high-pass" version, the radio frequency (RF) coil is made up of two conductive loop elements, each including serially-connected capacitors. The loop elements are electrically interconnected by axial conductive segments having inherent inductances associated therewith. Electrically, the coil can be viewed as a slow wave delay line structure wrapped around a cylinder and connected to itself. The coil can be energized by connecting a source of RF power across one of the capacitors in the loop elements. In another embodiment, termed the "band-pass" version, the axial conductive segments, as well as the conductive loop elements, are provided with capacitors.

摘要翻译： 在一个实施例中，被称为“高通”版本，射频（RF）线圈由两个导电环路元件组成，每个包括串联连接的电容器。 环形元件通过具有与其相关联的固有电感的轴向导电段电互连。 电气地，线圈可以被看作是围绕圆筒缠绕并连接到其自身的慢波延迟线结构。 通过在环路元件中的一个电容器之间连接RF电源来激励线圈。 在称为“带通”版本的另一实施例中，轴向导电段以及导电环路元件设置有电容器。

公开(公告)号：US5017872A

公开(公告)日：1991-05-21

申请号：US467475

申请日：1990-01-19

申请人： Thomas K. Foo ,  Cecil E. Hayes ,  Yoon-Won Kang

发明人： Thomas K. Foo ,  Cecil E. Hayes ,  Yoon-Won Kang

IPC分类号： A61B5/055 ,  G01R33/34 ,  G01R33/422

CPC分类号： G01R33/34076 ,  G01R33/422 ,  G01R33/5659

摘要： An RF coil assembly for an NMR instrument includes a cylindrical coil surrounded by a cylindrical shield. The annular space between the coil and the shield is filled with a dielectric material having a relative permittivity selected to improve the RF field homogeneity in the radial direction.

摘要翻译： 用于NMR仪器的RF线圈组件包括由圆柱形屏蔽件围绕的圆柱形线圈。 线圈和屏蔽之间的环形空间填充有选择的相对介电常数的介电材料，以改善径向方向的RF场均匀性。

公开(公告)号：US4887039A

公开(公告)日：1989-12-12

申请号：US288668

申请日：1988-12-22

申请人： Peter B. Roemer ,  William A. Edelstein ,  Cecil E. Hayes ,  Matthew G. Eash

发明人： Peter B. Roemer ,  William A. Edelstein ,  Cecil E. Hayes ,  Matthew G. Eash

IPC分类号： H01Q1/50 ,  A61B5/055 ,  G01R33/34 ,  G01R33/36

CPC分类号： G01R33/34046 ,  G01R33/3628

摘要： A method for providing plural coaxial cable connections, each to a different portion of a single radio-frequency (RF) antenna without requiring the use of isolation means at any RF connection, determines at least a point within the antenna having a desired common potential adjacent to each of the different portions to which one of the coaxial cable connections is to be made; Then forms a separate segment of each different portion which is located substantially at the common potential and is reactively separated from adjacent segments of the associated portion; and connects a shield conductor of an associated coaxial cable to the separate segment, while connecting a center conductor of that same associated coaxial cable to a selected one of the adjacent segments of that different portion.

公开(公告)号：US4947121A

公开(公告)日：1990-08-07

申请号：US446277

申请日：1989-12-05

申请人： Cecil E. Hayes

发明人： Cecil E. Hayes

IPC分类号： G01R33/341 ,  G01R33/3415

CPC分类号： G01R33/341 ,  G01R33/3415

摘要： A nuclear magnetic resonance (NMR) signal acquisition apparatus includes a cylindrical array of overlapping coils. Coupling of currents between coils due to re-radiation of received signals, in particular noise currents, is reduced by presenting a high impedance to each coil, thereby reducing the current circulating in each coil. A PREDAMP circuit is disclosed which utilizes the input impedance of a preamplifier, transformed through a quarter-wavelength transmission line segment, to achieve the high input impedance for the coil. As a result, multiple images, each with a high signal-to-noise ratio (SNR), can be simultaneoulsy obtained. A method is disclosed for combining the multiple images into a composite image with optimum SNR, taking into account the phase shifts between images resulting from the spatial orientation of the coils.

摘要翻译： 核磁共振（NMR）信号采集装置包括重叠线圈的圆柱形阵列。 由于接收信号的再辐射特别是噪声电流，线圈之间的电流耦合通过对每个线圈呈现高阻抗而减小，从而减少在每个线圈中循环的电流。 公开了一种PREDAMP电路，其利用通过四分之一波长传输线段转换的前置放大器的输入阻抗来实现线圈的高输入阻抗。 结果，可以同时获得具有高信噪比（SNR）的多个图像。 公开了一种用于将多个图像组合成具有最佳SNR的合成图像的方法，其考虑了由线圈的空间取向产生的图像之间的相移。

公开(公告)号：US4692705A

公开(公告)日：1987-09-08

申请号：US565254

申请日：1983-12-23

申请人： Cecil E. Hayes

发明人： Cecil E. Hayes

IPC分类号： G01R33/20 ,  A61B5/055 ,  A61B10/00 ,  G01R33/34 ,  G01R33/48 ,  H01F5/00

CPC分类号： G01R33/34046 ,  G01R33/34007

摘要： An NMR radio-frequency coil is made up of a plurality of conductive segments evenly spaced about the peripheries and interconnecting a pair of conductive end-cap elements. Each conductive segment includes at least one reactive element which may include a variable capacitive or inductive element.

摘要翻译： NMR射频线圈由围绕周边均匀隔开的多个导电段构成并且互连一对导电端帽元件。 每个导电段包括至少一个电抗元件，其可以包括可变电容或电感元件。

公开(公告)号：US06888153B2

公开(公告)日：2005-05-03

申请号：US09826326

申请日：2001-04-04

申请人： Cecil E. Hayes

发明人： Cecil E. Hayes

IPC分类号： G01R33/422 ,  G21F1/00 ,  G21C11/00 ,  G21F3/00 ,  G21F5/00 ,  G21F7/00

CPC分类号： G01R33/422

摘要： RF magnetic shields which support tangential electric fields. The RF shields are particularly suited for use in magnetic resonance imaging (MRI) systems, but may also be used in other radio frequency applications. The RF magnetic shields may include a dielectric layer having conductive regions separated by non-conductive regions on each side thereof to form a plurality of capacitive elements. The capacitive elements are partially non-conductive at radio frequencies such that the electrical component tangent to the shield is supported and the magnetic component perpendicular to the shield is blocked. The size and shape of the non-conductive and conductive regions are selected to develop a capacitive voltage across the capacitive elements at radio frequencies, and be substantially non-conductive at frequencies other than RF. The RF magnetic shields provide an electrical field that is uniform around the entire sample volume.

摘要翻译： 支持切向电场的RF磁屏蔽。 RF屏蔽特别适用于磁共振成像（MRI）系统，但也可用于其他射频应用。 RF磁屏蔽可以包括具有导电区域的介电层，该导电区域在其每侧由非导电区域分隔开以形成多个电容元件。 电容元件在无线电频率下部分不导电，使得与屏蔽件相切的电气部件被支撑并且垂直于屏蔽件的磁性部件被阻挡。 选择非导电和导电区域的尺寸和形状以在射频上在电容元件两端产生电容性电压，并且在除RF之外的频率上基本上不导电。 RF磁屏蔽提供围绕整个样品体积均匀的电场。

公开(公告)号：US5081418A

公开(公告)日：1992-01-14

申请号：US518009

申请日：1990-04-30

申请人： Cecil E. Hayes ,  Matthew G. Eash ,  Scott A. Weiss

发明人： Cecil E. Hayes ,  Matthew G. Eash ,  Scott A. Weiss

IPC分类号： A61B5/055 ,  G01R33/34 ,  G01R33/36

CPC分类号： G01R33/34046 ,  G01R33/3635

摘要： A method of tuning a radio frequency coil for use in MR imaging applications uses reactive shunts having a reactance in parallel with a switch to connect sections of the coil to ground thereby constraining the resonant mode of the coil to a known orientation. A plurality of measurements of the frequency of the resonances along different such constrained orientations is used to deduce the frequencies of the two unconstrained orthogonal resonant modes of the coil and its orientation. The shunts may also be used to tune the coil according to the deduced frequencies of the unconstrained resonance and the desired frequency and orientation by adjusting the reactance of the shunts. A shunt having a variable reactance and a switch for shorting the RF coil as required uses a PIN diode in combination with a variable reactance.

公开(公告)号：US5053711A

公开(公告)日：1991-10-01

申请号：US467474

申请日：1990-01-19

申请人： Cecil E. Hayes ,  Thomas K. Foo

发明人： Cecil E. Hayes ,  Thomas K. Foo

IPC分类号： A61B5/055 ,  G01R33/34 ,  G01R33/422

CPC分类号： G01R33/3453 ,  G01R33/34046 ,  G01R33/422

摘要： An RF coil assembly for an NMR instrument includes a cylindrical shield which encloses a set of equally spaced linear conductors that surround a central axis. A set of shielded conductors connect to the ends of the linear conductors to form loops. The effective lengths of the loops and the RF signal source which drives the loops are selected to improve the homogeneity of the RF field produced along the central axis.

摘要翻译： 用于NMR仪器的RF线圈组件包括圆柱形屏蔽件，其包围围绕中心轴线的一组等距间隔的线性导体。 一组屏蔽导体连接到线性导体的端部以形成环路。 选择驱动环路的环路和RF信号源的有效长度以改善沿着中心轴产生的RF场的均匀性。

公开(公告)号：US4885541A

公开(公告)日：1989-12-05

申请号：US234360

申请日：1988-08-19

申请人： Cecil E. Hayes

发明人： Cecil E. Hayes

IPC分类号： G01R33/341 ,  G01R33/3415 ,  G01R33/20

CPC分类号： G01R33/341 ,  G01R33/3415

摘要： A nuclear magnetic resonance (NMR) signal acquisition apparatus includes a cylindrical array of overlapping coils. Coupling of currents between coils due to re-radiation of received signals, in particular noise currents, is reduced by presenting a high impedance to each coil, thereby reducing the current circulating in each coil. A PREDAMP circuit is disclosed which utilizes the input impedance of a preamplifier, transformed through a quarter-wavelength transmission line segment, to achieve the high input impedance for the coil. As a result, multiple images, each with a high signal-to-noise ratio (SNR), can be simultaneously obtained. A method is disclosed for combining the multiple images into a composite image with optimum SNR, taking into account the phase shifts between the images resulting from the spatial orientation of the coils.

摘要翻译： 核磁共振（NMR）信号采集装置包括重叠线圈的圆柱形阵列。 由于接收信号的再辐射特别是噪声电流，线圈之间的电流耦合通过对每个线圈呈现高阻抗而减小，从而减少在每个线圈中循环的电流。 公开了一种PREDAMP电路，其利用通过四分之一波长传输线段转换的前置放大器的输入阻抗来实现线圈的高输入阻抗。 结果，可以同时获得具有高信噪比（SNR）的多个图像。 公开了一种用于将多个图像组合成具有最佳SNR的合成图像的方法，其考虑了由线圈的空间取向产生的图像之间的相移。

公开(公告)号：US5329233A

公开(公告)日：1994-07-12

申请号：US988542

申请日：1992-12-10

申请人： Cecil E. Hayes

发明人： Cecil E. Hayes

IPC分类号： G01R33/34 ,  G01R33/3415 ,  G01V3/00

CPC分类号： G01R33/3415 ,  G01R33/365 ,  G01R33/34007 ,  G01R33/34061

摘要： A local coil for magnetic resonance imaging employs a cylindrical form supporting a coil array of one or more coil groups arranged circumferentially around the cylindrical form. Multiple coil groups are overlapped to provide electrical isolation between the coil groups preserving the signal to noise ratio inherent in a local coil while providing a greater field-of-view than may be obtained from such coil group.

摘要翻译： 用于磁共振成像的局部线圈采用支撑围绕圆柱形形状周向布置的一个或多个线圈组的线圈阵列的圆柱形形式。 多个线圈组重叠以在线圈组之间提供电隔离，保持本地线圈固有的信噪比，同时提供比从这种线圈组获得的更大的视场。