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31.发明授权Efficiently shielded MRI gradient coil with discretely or continuously variable field of view 失效具有离散或连续可变视野的高效屏蔽MRI梯度线圈公开(公告)号：US06479999B1
公开(公告)日：2002-11-12
申请号：US09874773
申请日：2001-06-05
IPC分类号： G01V300
CPC分类号： G01R33/4215 , G01R33/3875
摘要： A gradient coil assembly generates magnetic field gradients across the main magnetic field of a magnetic resonance imaging apparatus and includes a primary gradient coil (22p) switchable between a first configuration which generates magnetic field gradients which are substantially linear over a first useful imaging volume, and a second configuration which generates magnetic field gradients which are substantially linear over a second useful imaging volume. A first shield coil set (22s1) is complimentary to the primary gradient coil in one of the first and second configurations, and a second shield coil set (22s2), when either used alone or in combination with the first shield coil, is complimentary to the other of the first and second configurations.
摘要翻译： 梯度线圈组件在磁共振成像设备的主磁场上产生磁场梯度，并且包括可在第一配置之间切换的主梯度线圈（22p），所述第一配置产生在第一有用成像体积上基本上线性的磁场梯度;以及 产生在第二有用成像体积上基本上线性的磁场梯度的第二配置。 第一屏蔽线圈组（22s1）在第一和第二配置之一中与主梯度线圈互补，并且当单独使用或与第一屏蔽线圈组合使用时，第二屏蔽线圈组（22s2）与 第一和第二配置中的另一个。
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公开(公告)号：US06441615B1
公开(公告)日：2002-08-27
申请号：US09473072
申请日：1999-12-28
IPC分类号： G01V300
CPC分类号： G01R33/3415 , G01R33/34 , G01R33/34061
摘要： A crossed-ladder RF coil assembly (48) is employed for quadrature excitation and/or reception in an open or vertical field magnetic resonance apparatus. The RF coil assembly (48, 70, 90) includes a pair of coil assemblies (50, 52; 70, 72; 100, 102) which are disposed in a parallel relationship. Coil arrays (50, 52; 100, 102) include at least two ladder RF coils (501, 502, 503; 521, 522, 523; 1001 . . . , 1008; 1021, . . . , 1028) which are disposed in an overlapping relationship and are rotated by 90° relative to one another. Each ladder RF coil of one coil array is rotated by 90° relative to adjoining ladder coils and each corresponding ladder RF coil of the other coil array. The crossed-ladder RF coil assembly provides better B1 field uniformity and elongated anatomical coverage for spine and neck imaging. In addition, the RF coil assembly reduces noise from the body at higher fields in vertical field magnetic resonance systems.
摘要翻译： 交叉梯形RF线圈组件（48）用于开放或垂直场磁共振装置中的正交激励和/或接收。 RF线圈组件（48,70,90）包括以平行关系设置的一对线圈组件（50,52; 70,72; 100,102）。 线圈阵列（50,52; 100,102）包括至少两个梯形RF线圈（501,502,503; 521,522,523; 1001 ... 1008; 1021，...，1028） 重叠关系并相对于彼此旋转90°。 一个线圈阵列的每个梯形RF线圈相对于邻接的梯形线圈和另一个线圈阵列的每个对应的梯形RF线圈旋转90°。 交叉梯形RF线圈组件为脊柱和颈部成像提供更好的B1场均匀性和细长的解剖学覆盖。 此外，RF线圈组件在垂直场磁共振系统中在较高场中减少来自身体的噪声。
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公开(公告)号：US06023167A
公开(公告)日：2000-02-08
申请号：US13617
申请日：1998-01-26
IPC分类号： A61B5/055 , G01R33/3875 , G01V3/00
CPC分类号： G01R33/3875
摘要： A localized shim coil (34) for use in a magnetic resonance imaging system includes a plurality of conductive elements (22a-d). The plurality of conductive elements (62a-d) are connected to a current source (64). The plurality of conductive elements (62a-d) are arranged adjacent to a localized region of a subject being imaged such that current flowing through the conductive elements generates a localized magnetic field. A plurality of series connected choke and resister pairs (66a-d) and (68a-d), respectively, are connected to the plurality of conductive elements (62a-d). The chokes (66a-d) present high impedance to currents having frequencies substantially the same as a resonant frequency of the magnetic resonance imaging system. The resisters (68a-d) balance the current flowing through each conductive element (62a-d). The localized magnetic field is generated such that it is substantially equal and opposite to localized non-uniformities generated in the magnetic resonance system's main magnetic field by the subject's geometric shape and magnetic susceptibility in the localized region being imaged.
摘要翻译： 用于磁共振成像系统的局部匀浆线圈（34）包括多个导电元件（22a-d）。 多个导电元件（62a-d）连接到电流源（64）。 多个导电元件（62a-d）被布置为邻近被成像对象的局部区域，使得流过导电元件的电流产生局部磁场。 多个串联的扼流圈和电阻对（66a-d）和（68a-d）分别连接到多个导电元件（62a-d）。 扼流圈（66a-d）对具有与磁共振成像系统的谐振频率基本相同的频率的电流呈现高阻抗。 电阻（68a-d）平衡流过每个导电元件（62a-d）的电流。 产生局部磁场，使得其与磁共振系统的主磁场中产生的局部不均匀性基本上相等并且与被摄体的几何形状和被成像的局部区域内的磁化率相反。
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公开(公告)号：US5406204A
公开(公告)日：1995-04-11
申请号：US80413
申请日：1993-06-21
IPC分类号： G01R33/20 , A61B5/055 , G01R33/3815 , G01R33/385 , G01R33/421 , G01R33/422
CPC分类号： G01R33/3815 , G01R33/385 , G01R33/421 , G01R33/422 , G01R33/3856 , G01R33/4215
摘要： The magnetic field assembly of a magnetic resonance imaging device includes an annular superconducting magnet (10) which is mounted within a toroidal vacuum vessel (24). A cylindrical member (26) defines a central bore through which the superconducting magnets generate a temporally constant primary magnetic field. A cylindrical, dielectric former (46) is mounted in the bore displaced a small distance from the cylindrical member. A radio frequency coil (32) is mounted within the cylindrical member defining a patient receiving examination region. An RF shield (34) is mounted around the exterior peripheral surface of the former. Primary gradient coils (40) are mounted around and potted to the exterior of the dielectric former around the RF shield. Gradient shield or secondary coils (44) are potted around an exterior of the cylindrical member within the vacuum chamber. As illustrated in FIG. 3 , when unshielded gradient coils are used, the primary gradient coils and the RF shield are mounted around the outer diameter of the cylindrical member (26).
摘要翻译： 磁共振成像装置的磁场组件包括安装在环形真空容器（24）内的环形超导磁体（10）。 圆柱形构件（26）限定中心孔，超导磁体通过该中心孔产生时间上不变的初级磁场。 圆柱形电介质成形器（46）安装在距离圆柱形构件较小距离的孔中。 射频线圈（32）安装在限定患者接收检查区域的圆柱形构件内。 RF屏蔽件（34）围绕前者的外周表面安装。 初级梯度线圈（40）围绕RF屏蔽件安装在电介质成形器的外部并且封装在外部。 梯度屏蔽或次级线圈（44）围绕真空室内的圆柱形构件的外部进行灌封。 如图1所示。 如图3所示，当使用非屏蔽梯度线圈时，主梯度线圈和RF屏蔽围绕圆柱形部件（26）的外径安装。
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公开(公告)号：US5349297A
公开(公告)日：1994-09-20
申请号：US80566
申请日：1993-06-21
IPC分类号： G01N33/38 , G01R33/34 , G01R33/3815 , G01R33/385 , G01R33/3875 , G01R33/421 , G01R33/422 , G01R33/20
CPC分类号： G01R33/3873 , G01R33/3815 , G01R33/385 , G01R33/3856 , G01R33/421 , G01R33/422 , G01R33/4215
摘要： The magnetic field assembly of a magnetic resonance imaging device includes an annular superconducting magnet (10) which is mounted within a toroidal vacuum vessel (24). A cylindrical member (26) defines a central bore (12) through which the superconducting magnets generate a uniform, static magnetic field. A cylindrical, dielectric former (46) is mounted in the bore displaced by an annular gap (58) from the cylindrical member. A shimset (60) for shimming the uniformity of the magnetic field is mounted in the gap (58). A radio frequency coil (32) is mounted within the cylindrical member defining a patient receiving examination region. An RF shield (34) is mounted around the exterior peripheral surface of the former. Primary gradient coils (50, 52, 54) are mounted around and potted to the exterior of the dielectric former around the RF shield. Gradient shield or secondary coils (74, 76, 78) are potted around an exterior of the cylindrical member within the vacuum chamber.
摘要翻译： 磁共振成像装置的磁场组件包括安装在环形真空容器（24）内的环形超导磁体（10）。 圆柱形构件（26）限定了中心孔（12），超导磁体通过该中心孔产生均匀的静态磁场。 一个圆柱形的电介质成形器（46）安装在由圆柱形构件的环形间隙（58）移位的孔中。 在间隙（58）中安装用于对磁场的均匀性进行匀场的垫片（60）。 射频线圈（32）安装在限定患者接收检查区域的圆柱形构件内。 RF屏蔽件（34）围绕前者的外周表面安装。 初级梯度线圈（50,52,54）围绕RF屏蔽件安装在电介质成形器的外部并封装在外部。 梯度屏蔽或次级线圈（74,76,78）围绕真空室内的圆柱形构件的外部进行灌封。
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公开(公告)号：US5280247A
公开(公告)日：1994-01-18
申请号：US859154
申请日：1992-03-27
IPC分类号： A61B5/055 , G01R33/20 , G01R33/385 , G01R33/421
CPC分类号： G01R33/385
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 magnetic assembly around the examination region. The superconducting magnet includes a hollow, tubular vacuum vessel (40) which contains a plurality of annular superconducting magnets (58). These superconducting magnets are held in a liquid helium holding reservoir (60) such that they are held below their superconducting temperature. A first cold shield (44) and a second cold shield (50 ) have tubular portions between the superconducting magnets and the examination region. These cylindrical portions each include a cylinder (70) of a electrically insulating material such as reinforced plastic. Thermally conductive layers (72) are defined on each surface and are divided by etched slots or resistance portions (74) into a multiplicity of elongated narrow segments (92). The narrow segments are constructed of a thermally conductive material, such as copper or aluminum, that also happens to be electrically conductive. The division of the foil layer into a multiplicity of segments divides the generated eddy currents into a like multiplicity of substantially canceling eddy currents (82) increasing the eddy current path length, increasing the total electrical resistance encountered, and reducing the amplitude and time constant of the resultant net eddy current and eddy magnetic field.
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）被布置在围绕检查区域的超导磁性组件的孔内。 超导磁体包括中空管状真空容器（40），其包含多个环形超导磁体（58）。 这些超导磁体被保持在液氦保持容器（60）中，使得它们保持在其超导温度以下。 第一冷屏蔽（44）和第二冷屏蔽（50）在超导磁体和检查区域之间具有管状部分。 这些圆柱形部分各自包括诸如增强塑料的电绝缘材料的圆筒（70）。 导热层（72）被限定在每个表面上，并被蚀刻的槽或电阻部分（74）分成多个细长窄段（92）。 窄段由也可能导电的导热材料（例如铜或铝）构成。 将箔层划分为多个段将生成的涡流分成相当大量的基本上消除的涡流（82），增加涡流路径长度，增加所遇到的总电阻，并减小振幅和时间常数 得到的净涡流和涡流磁场。
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公开(公告)号：US20100290683A1
公开(公告)日：2010-11-18
申请号：US12740358
申请日：2008-10-29
IPC分类号： G06K9/00
CPC分类号： G01R33/481 , A61B5/0035 , A61B5/0402 , A61B5/055 , A61B5/08 , A61B5/7289 , A61B5/7292 , A61B6/037 , A61B6/5247 , A61B6/5288 , A61B6/541 , G01R33/56509 , G01R33/5673 , G01R33/5676
摘要： In preparation for acquiring PET image data, subject motion models are built based on physiologic signal monitoring and MR data is collected and used for improved PET imaging. The physiologic signal monitoring is also used during PET imaging, and the acquired MR data is used for prospective or retrospective gating of the PET image acquisition, or in the PET reconstruction for improved correction/imaging.
摘要翻译： 为准备获取PET图像数据，基于生理信号监测建立主题运动模型，收集MR数据并用于改进PET成像。 生物信号监测也用于PET成像，采集的MR数据用于PET图像采集的前瞻性或回顾性门控，或PET重建中用于改善校正/成像。
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公开(公告)号：US07276906B2
公开(公告)日：2007-10-02
申请号：US10535530
申请日：2003-10-29
IPC分类号： G01V3/00
CPC分类号： G01R33/385 , G01R33/421 , G01R33/4215
摘要： A gradient coil for a magnetic resonance imaging apparatus (10) includes a primary coil (16) defining an inner cylindrical surface (60), and shield coil (18) or coils defining a coaxial outer cylindrical surface (62). Coil jumps (74)connect the primary and shield coils (16, 18). The coil jumps (74) define a non-planar current-sharing surface (64) extending between inner and outer contours (66, 68) that coincide with the inner and outer cylindrical surfaces (60, 62), respectively. The coil (16, 18, 74) defines a current path that passes across the current sharing surface (64) between the inner and outer contours (66, 68) a plurality of times. Optionally, some primary coil turns (70) are electrically interconnected to define an isolated primary sub coil (P2) that together with a second shield (S2, S2′, S2″) enables a discretely or continuously selectable field of view.
摘要翻译： 用于磁共振成像装置（10）的梯度线圈包括限定内圆柱形表面（60）的初级线圈（16）和限定同轴外圆柱形表面（62）的屏蔽线圈（18）或线圈。 线圈跳跃（74）连接主和屏蔽线圈（16,18）。 线圈跳跃（74）限定分别在与内圆柱形表面（60）和外圆柱形表面（62）重合的内外轮廓（66,68）之间延伸的非平面分流表面（64）。 线圈（16,18,74）限定了在内外轮廓（66,68）之间穿过电流共享表面（64）多次的电流路径。 可选地，一些初级线圈匝（70）电互连以限定与第二屏蔽（S 2，S 2'，S 2“）一起的隔离的初级次级线圈（P 2），使得能够离散地或连续地选择 视图。
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公开(公告)号：US6100695A
公开(公告)日：2000-08-08
申请号：US454513
申请日：1999-12-06
IPC分类号： A61B5/055 , G01R33/3875 , G01V3/00
CPC分类号： G01R33/3875
摘要： A localized shim coil (34) for use in a magnetic resonance imaging system includes a plurality of conductive elements (22a-d). The plurality of conductive elements (62a-d) are connected to a current source (64). The plurality of conductive elements (62a-d) are arranged adjacent to a localized region of a subject being imaged such that current flowing through the conductive elements generates a localized magnetic field. A plurality of series connected choke and resister pairs (66a-d) and (68a-d), respectively, are connected to the plurality of conductive elements (62a-d). The chokes (66a-d) present high impedance to currents having frequencies substantially the same as a resonant frequency of the magnetic resonance imaging system. The resisters (68a-d) balance the current flowing through each conductive element (62a-d). The localized magnetic field is generated such that it is substantially equal and opposite to localized non-uniformities generated in the magnetic resonance system's main magnetic field by the subject's geometric shape and magnetic susceptibility in the localized region being imaged.
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40.发明授权
公开(公告)号：US6011394A
公开(公告)日：2000-01-04
申请号：US908359
申请日：1997-08-07
IPC分类号： G01R33/385 , A61B5/055 , G01R33/421 , H01F7/20 , G01V3/00
CPC分类号： G01R33/4215 , G01R33/3856
摘要： A superconducting magnetic imaging apparatus includes a vacuum vessel (16) having a central helium reservoir (20) in which superconducting magnetic coil windings (12) are maintained at a superconducting temperature. The vacuum vessel defines an internal bore (22) within which a self-shielded gradient coil assembly (26) and an RF coil (30) are received. The self-shielded coil assembly includes a single former (50) which defines an imaging region (14) within which an imaged portion of a subject is received. Primary x, y, and z-gradient coils (72-76) are positioned over an RF ground screen (70) that is bonded to the former (50). A number of comb-like spacers (84) extend from the former to supporting shield x, y, and z-gradient coils (110-114). The comb-like spacers define passages between the primary and secondary gradient coils which receive inner and outer cooling tubes (90, 92) and shim tray molds (108). The fully assembled gradient coil assembly is potted to form a unitary structure in a single potting step. The shim tray molds are subsequently removed to define channels or pockets suitable for receiving shim trays (118).
摘要翻译： 超导磁性成像装置包括具有中心氦储存器（20）的真空容器（16），超导磁性线圈绕组（12）保持在超导温度下。 真空容器限定内部孔（22），在其内接收自屏蔽梯度线圈组件（26）和RF线圈（30）。 自屏蔽线圈组件包括限定成像区域（14）的单个成形器（50），在该成像区域内接收被摄体的成像部分。 主x，y和z梯度线圈（72-76）位于结合到前者（50）的RF接地屏（70）上。 多个梳状间隔物（84）从前者延伸到支撑屏蔽x，y和z-梯度线圈（110-114）。 梳状间隔件限定了接收内部和外部冷却管（90,92）和垫片托盘模具（108）的主梯度线圈和次级梯度线圈之间的通道。 完全组装的梯度线圈组件被封装以在单个灌封步骤中形成单一结构。 随后卸下垫片托盘模具以限定适于接收垫片托盘（118）的通道或袋子。
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