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公开(公告)号：US06552538B2
公开(公告)日：2003-04-22
申请号：US09833003
申请日：2001-04-11
IPC分类号： G01V300
CPC分类号： G01R33/583
摘要： A pair of quadrature radio frequency coils (32, 34) disposed adjacent an imaging region (10) are typically loaded differently due to factors such as subject geometry, subject mass, and a relative distance from the subject. A tip angle adjustment circuit (50) monitors a combined tip angle adjacent a mid-plane of the examination region, such as by analyzing delivered and reflected power to each of the coils. An adjustment circuit (54) adjusts relative RF power or amplitude to produce a selected, combined tip angle in the examination region.
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公开(公告)号：US08441259B2
公开(公告)日：2013-05-14
申请号：US12742976
申请日：2008-12-12
申请人： Zhiyong Zhai , Robert Gauss , Eddy Yu Ping Wong , Michael A. Morich , Kevin M. Nieman , Gordon D. DeMeester
发明人： Zhiyong Zhai , Robert Gauss , Eddy Yu Ping Wong , Michael A. Morich , Kevin M. Nieman , Gordon D. DeMeester
IPC分类号： G01V3/00
CPC分类号： G01R33/3415 , G01R33/5659
摘要： A magnetic resonance coil comprises a first set of coil elements (54, 56, 80) operatively connectable with a transmit channel (66, 74) to couple with a transmit region of sensitivity for a selected load at a magnetic field strength greater than 3 Tesla, and a second set of coil elements (52, 54, 82) operatively connectable with a receive channel (66, 74) to couple with a receive region of sensitivity for the selected load at the magnetic field strength greater than 3 Tesla. The first set of coil elements is arranged proximate to but not surrounding the transmit region of sensitivity, and the second set of coil elements is arranged proximate to but not surrounding the receive region of sensitivity. The first set of coil elements and the second set of coil elements having at least one coil element (52, 56) not in common. The first and second sets of coil elements define transmit and receive regions of sensitivity for the selected load at the magnetic field strength greater than 3 Tesla that are substantially similar.
摘要翻译： 磁共振线圈包括可操作地与发射通道（66,74）连接的第一组线圈元件（54,56,80），以在大于3特斯拉的磁场强度下与选定负载的灵敏度的发射区域耦合 以及第二组线圈元件（52,54,82），其可操作地与接收通道（66,74）连接，以在大于3特斯拉的磁场强度下与所选择的负载的接收灵敏度区域耦合。 第一组线圈元件布置成靠近但不围绕灵敏度的发射区域，并且第二组线圈元件布置成接近但不包围灵敏度的接收区域。 第一组线圈元件和第二组线圈元件具有不共同的至少一个线圈元件（52,56）。 第一组和第二组线圈元件在大于3特斯拉的大于3特斯拉的磁场强度下为所选择的载荷定义灵敏度的发射和接收区域。
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3.发明授权公开(公告)号：US08089281B2
公开(公告)日：2012-01-03
申请号：US12528541
申请日：2008-01-30
IPC分类号： G01V3/00
CPC分类号： G01R33/3635 , G01R33/34007 , G01R33/341 , G01R33/3678
摘要： A radio frequency coil comprises an annular conductor or parallel annular conductors (22, 22c, 22d) configured to support: (i) a uniform electrical current distribution generating a first B1 field (B1,uniform) at a first magnetic resonance frequency directed out of a plane of the annular conductor or conductors; and (ii) a sinusoidal electrical current distribution generating a second B1 field (B1,sine) at a second magnetic resonance frequency directed parallel with the plane of the annular conductor or conductors. A magnetic resonance scanner comprises: a magnet (10) generating a static magnetic field (B0); a magnetic field gradient system (14) configured to superimpose selected magnetic field gradients on the static magnetic field; and said radio frequency coil including said annular conductor or parallel annular conductors (22, 22c, 22d).
摘要翻译： 射频线圈包括环形导体或平行环形导体（22,22c，22d），其被配置为支持：（i）均匀的电流分布，其以第一磁共振频率产生第一B1场（B1，均匀） 环形导体或导体的平面; 和（ii）以与环形导体或导体的平面平行的第二磁共振频率产生第二B1场（B1，正弦）的正弦电流分布。 磁共振扫描器包括：产生静磁场（B0）的磁体（10）; 磁场梯度系统（14），被配置为将选定的磁场梯度叠加在静磁场上; 并且所述射频线圈包括所述环形导体或平行环形导体（22,22c，22d）。
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公开(公告)号：US07683623B2
公开(公告)日：2010-03-23
申请号：US11917010
申请日：2006-06-13
IPC分类号： G01V3/00
CPC分类号： G01R33/34046 , G01R33/3664
摘要： A radio frequency coil for magnetic resonance imaging or spectroscopy includes a plurality of generally parallel conductive members (70) surrounding a region of interest (14). One or more end members (72, 74) are disposed generally transverse to the plurality of parallel conductive members. A generally cylindrical radio frequency shield (32) surrounds the plurality of generally parallel conductive members. Switchable circuitry (80, 80′) selectably has: (i) a first switched configuration (90, 90′) in which the conductive members are operatively connected with the one or more end members; and (ii) a second switched configuration (92, 92′) in which the conductive members are operatively connected with the radio frequency shield. The radio frequency coil operates in a birdcage resonance mode in the first switched configuration and operates in a TEM resonance mode in the second switched configuration.
摘要翻译： 用于磁共振成像或光谱的射频线圈包括围绕感兴趣区域（14）的多个大致平行的导电构件（70）。 一个或多个端部构件（72,74）大致横向于多个平行导电构件设置。 通常为圆柱形的射频屏蔽（32）围绕多个大致平行的导电构件。 可切换电路（80,80'）可选择地具有：（i）第一开关构造（90,90'），其中导电构件与一个或多个端构件可操作地连接; 和（ii）其中导电构件与射频屏蔽可操作地连接的第二切换配置（92,92'）。 射频线圈在第一切换配置中以鸟笼共振模式工作，并且在第二切换配置中以TEM共振模式操作。
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公开(公告)号：US20080186026A1
公开(公告)日：2008-08-07
申请号：US11913487
申请日：2006-04-19
申请人： Christoph G. Leussler , Kai-Michael Luedeke , Michael A. Morich , Zhiyong Zhai , Gordon D. DeMeester
发明人： Christoph G. Leussler , Kai-Michael Luedeke , Michael A. Morich , Zhiyong Zhai , Gordon D. DeMeester
IPC分类号： G01R33/422
CPC分类号： G01R33/422 , G01R33/3628
摘要： A radio frequency coil for magnetic resonance imaging includes an active coil member (70, 701, 170, 270) that defines an imaging volume. The active coil member has a first open end (74) with a first cross-sectional dimension (dactive). A shield coil member (72, 721, 722, 723, 724, 725, 172, 1722, 272) substantially surrounds the active coil member. The shield coil member has a constricted open end (88) arranged proximate to the first open end of the active coil member with a constricted cross-sectional dimension (dconst) that is less than the cross-sectional dimension (dShieid) of the shield coil member In some embodiments, the radio frequency coil further includes an outer shield coil member (100) that is substantially larger than the shield coil member (72, 721, 722, 723, 724, 725, 172, 1722, 272), and surrounds both the active coil member and the shield coil member.
摘要翻译： 用于磁共振成像的射频线圈包括限定成像体积的有源线圈构件（70,70A，170,270）。 有源线圈构件具有第一横截面尺寸（dactive）的第一开口端（74）。 屏蔽线圈构件（72,72，...，72，72，72，72，SUB） 大致围绕有源线圈构件。 屏蔽线圈构件具有靠近有源线圈构件的第一开口端布置的收缩的开口端（88），其缩小的横截面尺寸（dconst）小于屏蔽线圈的横截面尺寸（dShid） 在一些实施例中，射频线圈还包括外屏蔽线圈构件（100），该屏蔽线圈构件（100）基本上大于屏蔽线圈构件（72,72，...，72 < ，72个3，72个，72个，172个，172个，272个），并且包围两个 有源线圈构件和屏蔽线圈构件。
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公开(公告)号：US20080164878A1
公开(公告)日：2008-07-10
申请号：US11908293
申请日：2006-03-03
IPC分类号： G01R33/3875
CPC分类号： G01R33/3875
摘要： In a magnetic resonance imaging system (10), a main magnet (20) generates a substantially uniform main magnetic field (B0) through an examination region (14). An imaging subject (16) generates inhomogeneities in the main magnetic field (B0). One or more shim coils are positioned adjacent a gradient coil (26). The gradient coil (26) is driven in halves by first and second power sources (28, 30) which have slightly dissimilar power characteristics which induce an inductive coupling between the shim coil (60) and the gradient coil (26). The shim coil (60) is designed to produce a desired magnetic field, such that the inductive coupling of the shim coils (60) to the gradient coil (26) is substantially minimized while the inhomogeneities in the main magnetic field (B0) caused by the imaging subject are corrected based on prespecified spatial characteristics.
摘要翻译： 在磁共振成像系统（10）中，主磁体（20）通过检查区域（14）产生基本上均匀的主磁场（B <0> 0）。 成像对象（16）在主磁场（B 0> 0）中产生不均匀性。 一个或多个垫片线圈邻近梯度线圈（26）定位。 梯度线圈（26）由具有稍微不相似的功率特性的第一和第二电源（28,30）驱动两半，其引起垫片线圈（60）和梯度线圈（26）之间的电感耦合。 垫片线圈（60）被设计成产生期望的磁场，使得垫片线圈（60）与梯度线圈（26）的电感耦合基本上最小化，而主磁场（B）中的不均匀性 基于预先确定的空间特性来校正由成像对象引起的0 ）。
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公开(公告)号：US6097187A
公开(公告)日：2000-08-01
申请号：US915624
申请日：1997-08-21
IPC分类号： G01R33/3815 , G01R33/3875 , G01V3/00
CPC分类号： G01R33/3815 , G01R33/3875
摘要： Primary superconducting coils (50) generate a magnetic field through an examination region (10). Stabilizing coils (70) are magnetically coupled with the magnetic field generated by the primary coils. A primary persistence switch (60) and a stabilizing coils persistence switch (72) are opened when the primary coils are connected to a current source (62) to ramp-up the magnetic field. The persistence switches are closed, disconnecting the primary coils from the current source and connecting the primary coils and the stabilizing coils into closed loops. As the magnetic flux generated by the primary coils fluctuates as the primary coils stabilize, the changing flux induces currents in the stabilizing coils. The currents induced in the stabilizing coils generate an offsetting magnetic flux such that the net magnetic flux generated by the primary and stabilizing coils is held constant.
摘要翻译： 初级超导线圈（50）通过检查区域（10）产生磁场。 稳定线圈（70）与由初级线圈产生的磁场磁耦合。 当初级线圈连接到电流源（62）以升高磁场时，主持续开关（60）和稳定线圈持续开关（72）打开。 持续开关闭合，将初级线圈与电流源断开，并将初级线圈和稳定线圈连接成闭合回路。 随着初级线圈产生的磁通量随着初级线圈的稳定而波动，变化的磁通会引起稳定线圈中的电流。 在稳定线圈中感应的电流产生偏移磁通，使得由初级和稳定线圈产生的净磁通保持恒定。
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公开(公告)号：US5289128A
公开(公告)日：1994-02-22
申请号：US859152
申请日：1992-03-27
IPC分类号： A61B5/055 , G01R33/20 , G01R33/38 , G01R33/385 , G01R33/421 , H01F6/00
CPC分类号： G01R33/3856 , G01R33/385 , G01R33/4215
摘要： An examination region (12) is defined within the bore of a superconducting magnet assembly (10). An RF coil (22) and gradient magnetic field coils (14) are disposed within the bore of the superconducting magnet assembly around the examination region. The superconducting magnet includes a hollow, cylindrical vacuum vessel (40). An annular, liquid helium holding low temperature reservoir (60) extends centrally through the vacuum vessel, but is sealed therefrom such that liquid helium is not drawn into the vacuum. A plurality of annular superconducting magnets (56) are received in the low temperature reservoir immersed in the liquid helium. A first cold shield (44) and a second cold shield (50) are mounted in the vacuum vessel surrounding the low temperature reservoir. A main magnetic field shield coil (66) is disposed in the low temperature reservoir outside of the annular superconducting magnets for canceling the magnetic field generated by the annular magnets surrounding the magnet. A gradient shield coil (70) is mounted in low temperature reservoir inside the annular superconducting magnets to cancel magnetic fields generated by the gradient magnetic field coils in the region beyond the gradient shield coil. The gradient shield coil is electromagnetically coupled to the gradient field coils to be driven by magnetic fields emanating therefrom. Optionally, the gradient shield coil can be constructed of a higher temperature superconducting material and disposed in association with one of the cold shields.
摘要翻译： 检查区域（12）被限定在超导磁体组件（10）的孔内。 RF线圈（22）和梯度磁场线圈（14）被布置在超导磁体组件的围绕检查区域的孔内。 超导磁体包括中空的圆柱形真空容器（40）。 一个环状的液氦保持低温储存器（60）在真空容器的中心延伸，但被密封，使得液氦不被吸入真空。 多个环形超导磁体（56）被容纳在浸入液氦的低温储存器中。 第一冷屏蔽（44）和第二冷屏蔽（50）安装在围绕低温储存器的真空容器中。 主磁场屏蔽线圈（66）设置在环形超导磁体外部的低温储存器中，用于抵消围绕磁体的环形磁体产生的磁场。 梯度屏蔽线圈（70）安装在环形超导磁体内部的低温储存器中，以消除梯度屏蔽线圈之外的区域中的梯度磁场线圈产生的磁场。 梯度屏蔽线圈与梯度场线圈电磁耦合，由其发出的磁场驱动。 可选地，梯度屏蔽线圈可以由更高温度的超导材料构成并且与其中一个冷屏蔽件相关联地设置。
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公开(公告)号：US20100219347A1
公开(公告)日：2010-09-02
申请号：US12670256
申请日：2008-06-23
CPC分类号： G01T1/1603
摘要： An imaging system includes positron emission tomography (PET) detectors (30) shrouded by broadband galvanic isolation (99) and coincidence detection electronics (50, 50ob), or other radiation detectors. A magnetic resonance scanner includes a main magnet (12, 14) and magnetic field gradient assembly (20, 20′, 22, 24) configured to acquire imaging data from a magnetic resonance examination region at least partially overlapping the examination region surrounded by the PET detectors. A radio frequency coil (80, 100) has plurality of conductors (66, 166) and a radio frequency screen (88, 188, 188EB, 188F) substantially surrounding the conductors to shield the coil at the magnetic resonance frequency. The radiation detectors are outside of the radio frequency screen. Magnetic resonance-compatible radiation collimators or shielding (60, 62) containing an electrically non-conductive and non-ferromagnetic heavy atom oxide material are disposed with the radiation detectors.
摘要翻译： 一种成像系统包括由宽带电流隔离（99）和重合检测电路（50,50ob）或其他辐射检测器覆盖的正电子发射断层摄影（PET）检测器（30）。 磁共振扫描仪包括主磁体（12,14）和磁场梯度组件（20,20'，22,24），其被配置为从至少部分地与由PET包围的检查区域重叠的磁共振检查区域获取成像数据 探测器 射频线圈（80,100）具有基本上围绕导体以屏蔽线圈的磁共振频率的多个导体（66,166）和射频屏（88,188,188EB，188F）。 辐射探测器在射频屏幕之外。 磁辐射准直仪或包含非导电和非铁磁重原子氧化物材料的屏蔽（60,62）与辐射探测器一起设置。
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公开(公告)号：US20100033186A1
公开(公告)日：2010-02-11
申请号：US12531979
申请日：2008-01-16
IPC分类号： G01R33/44
CPC分类号： G01R33/481 , A61B5/0035 , A61B5/055 , G01R33/385 , G01R33/3875 , G01R33/421 , G01R33/4215 , G01R33/4808
摘要： A generally cylindrical set of coil windings (10, 30, 80) includes primary coil windings (12, 32, 82) and shield coil windings (14, 34, 84) at a larger radial position than the primary coil windings, and an arcuate or annular central gap (16, 36, 86) that is free of coil windings, has an axial extent (W) of at least ten centimeters, and spans at least a 180° angular interval. Connecting conductors (24, 44, 94) disposed at each edge of the central gap electrically connect selected primary and secondary coil windings. In a scanner setting, a main magnet (62, 64) is disposed outside of the generally cylindrical set of coil windings. In a hybrid scanner setting, an annular ring of positron emission tomography (PET) detectors (66) is disposed in the central gap of the generally cylindrical set of coil windings.
摘要翻译： 一般为圆柱形的线圈绕组（10,30,80）包括在比初级线圈绕组更大的径向位置处的初级线圈绕组（12,32,82）和屏蔽线圈绕组（14,34,84），以及弧形 或没有线圈绕组的环形中心间隙（16,36,86）具有至少十厘米的轴向范围（W）并跨越至少180°的角度间隔。 设置在中心间隙的每个边缘处的连接导体（24,44,94）电连接所选择的初级和次级线圈绕组。 在扫描器设置中，主磁体（62,64）设置在大致圆柱形的线圈绕组的外侧。 在混合扫描器设置中，正电子发射断层摄影（PET）检测器（66）的环形环设置在大致圆柱形的线圈绕组组的中心间隙中。
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