-
1.发明授权Sampling-ring saturation pulse for two-dimensional magnetic resonance selective excitation 失效用于二维磁共振选择性激发的采样环饱和脉冲
公开(公告)号：US5313163A
公开(公告)日：1994-05-17
申请号：US928390
申请日：1992-08-12
IPC分类号： G01R33/48 , G01R33/483 , G01R33/565 , G01V3/00
CPC分类号： G01R33/446 , G01R33/5659 , G01R33/4838 , G01R33/56545
摘要： A method for suppressing sampling-ring artifacts produced by spiral-scan-based 2D selective excitation pulses, such as a those exciting a `pencil-shaped` region, employs a 2D annular saturation pulse followed by a gradient `crusher` lobe which dephases the transverse magnetization in the annular region. The annular saturation pulse is itself based on a spiral k-space trajectory having a limited number of cycles and a small outer radius, and is designed to saturate magnetization of tissue of the subject corresponding to the artifact rings of an excitation region while not affecting a central region. The annular saturation pulse may also be reshaped to limit the peak RF power to levels currently used for clinical MR imaging, while preserving bandwidth and the 2D excitation profile.
摘要翻译： 用于抑制由基于螺旋扫描的2D选择性激发脉冲（例如那些激发“铅笔形”）区域产生的采样环伪像的方法采用2D环形饱和脉冲，随后是梯度“破碎机” 环形区域的横向磁化强度。 环形饱和脉冲本身基于具有有限数量的周期和小的外半径的螺旋k空间轨迹，并且被设计为饱和对象于激发区域的假象环的对象的组织的磁化，同时不影响 中央区域。 环形饱和脉冲也可以被重新形成，以将峰值RF功率限制到目前用于临床MR成像的水平，同时保持带宽和2D激励分布。
-
公开(公告)号：US5192909A
公开(公告)日：1993-03-09
申请号：US637910
申请日：1991-01-07
CPC分类号： G01R33/446
摘要： An NMR system performs in vivo localized NMR spectroscopy. A two-dimensional selective RF excitation pulse is used to localize to a cylindrical region of interest, and either phase encoding or slice selective inversion is used to localize to a disk in the cylindrical region of interest. The two-dimensional selective RF excitation is performed in a series of pulse sequences rather than a single pulse sequence, and the resulting series of acquired NMR signals are summed together to substantially cancel signal conributions from outside the cylindrical region of interest.
摘要翻译： NMR体系进行体内局部NMR光谱。 使用二维选择性RF激励脉冲来定位到感兴趣的圆柱形区域，并且使用相位编码或切片选择性反转来定位到感兴趣的圆柱形区域中的盘。 二维选择性RF激励以一系列脉冲序列而不是单个脉冲序列执行，并且所得到的一系列获取的NMR信号被相加在一起以基本上消除来自感兴趣的圆柱体区域的信号。
-
公开(公告)号：US4973908A
公开(公告)日：1990-11-27
申请号：US370518
申请日：1989-06-23
IPC分类号： G01R33/36 , A61B5/055 , G01R33/32 , G01R33/34 , G01R33/341
CPC分类号： G01R33/341
摘要： An NMR antenna probe has at least one substantially circular surface coil arranged in a plane and a surface coil having substantially a Figure-8 shape, substantially coplanar with the at least one circular surface coil. The Figure-8 coil has a cross-over portion which is located substantially coaxial with the axis of the at least one circular surface coil. The coil corresponding to the least-NMR-sensitive nucleus is circular, while the non-circular coil corresponds to the most-NMR-sensitive nucleus. The circular coil is positioned on the side of the NMR probe closest to the subject to be studied.
-
公开(公告)号：US4695799A
公开(公告)日：1987-09-22
申请号：US746146
申请日：1985-06-18
CPC分类号： G01R33/446 , G01R33/3607
摘要： A method for the complete inversion of magnetization by adiabatic fast passage during an NMR experiment on a sample having a selected nuclear specie with a Larmor frequency .omega..sub.0. A radio-frequency magnetic field is generated with an amplitude B.sub.1 and an instantaneous frequency .omega.(t) which is non-linearly swept, as a function of time, from a minimum frequency .omega..sub.1 substantially at a maximum offset frequency .DELTA..omega. below the Larmor frequency .omega..sub.0, through the Larmor frequency, to a maximum frequency .omega..sub.h substantially at the maximum offset frequency .DELTA..sub..omega. above the Larmor frequency. The non-linearly swept, monotonic RF signal is applied to the sample-being-investigated for a sweep time interval sufficient to invert the magnetization of the selected nuclear specie. The preferred sweep is a tangential function:.omega.(t)=.omega..sub.0 .+-..gamma.B.sub.1 tan (arcsin (.omega..sub.s t)), (A)or.omega.(t)=.omega..sub.0 .+-..gamma.B.sub.1 tan (.omega..sub.s t)where .omega..sub.s =.alpha..gamma.B.sub.1, .gamma. is the gyromagnetic ratio of the selected nuclear specie and 0
摘要翻译： 在具有Larmor频率ω0的选定核子样品的NMR实验中通过绝热快速通过完全反转磁化的方法。产生具有振幅B1和瞬时频率ω（t）的射频磁场 ），其通过拉莫尔频率从基本上在低于拉莫尔频率ω0的最大偏移频率DELTAω的基本上最大频率ω1的最小频率ω1作为时间的非线性扫描到最大频率ωh 偏移频率DELTA omega高于拉莫尔频率。 将非线性扫描的单调RF信号施加到被研究的样品的扫描时间间隔，以足以反转所选择的核物种的磁化。 优选的扫描是切向函数：ω（t）=ω0 +/-γB1 tan（arcsin（ω）），（A）或ω（t）=ω0 +/-γB1 tan（ω） 其中ω=α伽马B1，γ是所选核物种的回磁比，0≤α= 1。
-
公开(公告)号：US20080100294A1
公开(公告)日：2008-05-01
申请号：US11554951
申请日：2006-10-31
IPC分类号： G01V3/00
CPC分类号： G01R33/3415 , G01R33/34007 , G01R33/34084
摘要： An RF coil assembly includes a plurality of coil supports rotatably interconnected to each other. Each coil support is configured to rotate with respect to at least one adjoining coil support. A plurality of RF coils is connected to each coil support.
摘要翻译： RF线圈组件包括可互相互连的多个线圈支架。 每个线圈支撑件构造成相对于至少一个相邻的线圈支撑件旋转。 多个RF线圈连接到每个线圈支架。
-
6.发明授权Method and apparatus for automated tracking of non-linear vessel movement using MR imaging 有权使用MR成像自动跟踪非线性血管运动的方法和装置公开(公告)号：US07209777B2
公开(公告)日：2007-04-24
申请号：US09728071
申请日：2000-11-30
IPC分类号： A61B5/05
CPC分类号： G01R33/56509 , A61B5/0037 , A61B5/055 , A61B5/7285 , G01R33/56 , G01R33/5673
摘要： A system and method is disclosed for tracking a moving object using magnetic resonance imaging. The technique includes acquiring a scout image scan having a number of image frames and extracting non-linear motion parameters from the number of image frames of the scout image scan. The technique includes prospectively shifting slice location using the non-linear motion parameters between slice locations while acquiring a series of MR images. The system and method are particularly useful in tracking coronary artery movement during the cardiac cycle to acquire the non-linear components of coronary artery movement during a diastolic portion of the R—R interval.
摘要翻译： 公开了一种使用磁共振成像跟踪运动物体的系统和方法。 该技术包括获取具有多个图像帧的侦察图像扫描，并从侦察图像扫描的图像帧的数量中提取非线性运动参数。 该技术包括使用切片位置之间的非线性运动参数前进移位切片位置，同时获取一系列MR图像。 该系统和方法在心脏周期期间跟踪冠状动脉运动特别有用，以在R-R间期的舒张期期间获得冠状动脉运动的非线性分量。
-
7.发明授权
公开(公告)号：US5578924A
公开(公告)日：1996-11-26
申请号：US558296
申请日：1995-11-15
CPC分类号： G01R33/4835 , G01R33/4833
摘要： A multi-planar imaging method employs magnetic resonance to detect image data from multiple planes within a subject. Data from each plane are detected in response to the same readout gradient and are simultaneously detected. The image planes can be arbitrarily oriented with respect to each other and with respect to the readout and phase-encoding image formation magnetic field gradient pulses if desired. Overlap of image data from each of the excited image planes in the acquired image is prevented by employing a thick refocusing slab oriented orthogonal to the readout and phase-encoding directions, or by choosing planes which intersect outside the subject's anatomy.
摘要翻译： 多平面成像方法采用磁共振来检测受试者内的多个平面的图像数据。 根据相同的读出梯度检测来自每个平面的数据，并同时检测。 如果需要，图像平面可以相对于彼此和相对于读出和相位编码图像形成磁场梯度脉冲任意取向。 通过采用与读出和相位编码方向正交取向的厚度重聚焦板，或通过选择与被摄体的解剖结构外部相交的平面来防止获取的图像中的每个激发的图像平面上的图像数据的重叠。
-
8.发明授权
公开(公告)号：US5512827A
公开(公告)日：1996-04-30
申请号：US460018
申请日：1995-06-02
CPC分类号： G01R33/54
摘要： A newly acquired MR image of an imaging subject is displayed on a display device. An operator interactively manipulates the imaging plane during imaging, by using a button, a rocker switch, a knob, and a trackball. The button enables or disables interactive scan-plane control. The rocker switch chooses between "translate", and "rotate" modes. In "translate" mode, the knob pushes the imaging plane deeper or shallower relative to the most recently displayed image, while the trackball slides the plane sideways and/or up and down. In "rotate" mode, the knob spins the imaging plane about the center of the most recently displayed image without changing the tilt of the plane, while the trackball tumbles or tilts the imaging plane. Colored icons displayed over the image change location, size, and/or shape to indicate the direction and extent of the translation or rotation. When motion of the knob or trackball ceases, or an acquire image button is pressed, the icon reassumes its default size, shape, and location, and the location and orientation information is transformed and provided to a pulse sequencer of a magnetic resonance (MR) imaging system. The pulse sequencer controls an RF transmitter and gradient amplifiers to cause an MR image of the subject at an imaging plane to be acquired. The new imaging-plane location is then used for all subsequent images, until another change is made.
摘要翻译： 在显示装置上显示摄像对象的新获取的MR图像。 操作者通过使用按钮，摇杆开关，旋钮和轨迹球在成像期间交互地操纵成像平面。 该按钮启用或禁用交互式扫描平面控制。 摇杆开关在“平移”和“旋转”模式之间进行选择。 在“翻译”模式中，旋钮将成像平面相对于最近显示的图像更深或更浅，同时轨迹球横向滑动平面和/或上下滑动。 在“旋转”模式下，旋钮将成像平面围绕最近显示的图像的中心旋转，而不会改变平面的倾斜，而轨迹球会翻转或倾斜成像平面。 在图像上显示的彩色图标更改位置，大小和/或形状，以指示翻译或旋转的方向和范围。 当旋钮或轨迹球的运动停止或按下获取的图像按钮时，图标重新确定其默认尺寸，形状和位置，并且将位置和方向信息变换并提供给磁共振（MR）的脉冲序列器， 成像系统。 脉冲序列发生器控制RF发射器和梯度放大器，以获得成像平面上的对象的MR图像。 然后将新的成像平面位置用于所有后续图像，直到进行另一个改变。
-
公开(公告)号：US06275035B1
公开(公告)日：2001-08-14
申请号：US09200165
申请日：1998-11-25
IPC分类号： G01V300
CPC分类号： G01R33/54
摘要： A method and apparatus for producing an imaging plane on an image of a structure of interest, such as an anatomical structure, positioned in an MRI system. An operator interactively pages through real-time, planar sections of the structure of interest. Using an input device, the operator selects three separate points in a planar section of the structure under study. Within approximately one second of selection of the third point, the method of the present invention determines the imaging plane containing the three selected points, determines the centroid of the imaging plane centered on a triangle defined by the three selected points, sends such imaging geometry and in-plane offsets of the imaging plane directly to the MRI system to generate a new imaging plane optimally positioned with respect to the selected points on the structure of interest and displaying such new imaging plane. The operator can also selectively maneuver the imaging plane on the image of the structure of interest. The operator uses a graphical user interface in conjunction with the input device and a display screen for producing the imaging plane on the structure of interest. Such graphical user interface is referred to as a three point tool.
摘要翻译： 一种用于在诸如解剖结构的感兴趣结构的图像上产生成像平面的方法和装置，其位于MRI系统中。 操作者通过交互式浏览感兴趣的结构的实时平面部分。 使用输入设备，操作员在正在研究的结构的平面部分中选择三个独立的点。 在第三点的选择大约一秒之内，本发明的方法确定包含三个选定点的成像平面，确定以由三个选定点定义的三角形为中心的成像平面的质心，发送这样的成像几何和 成像平面的面内偏移直接到MRI系统以产生相对于感兴趣的结构上的所选点最佳定位的新成像平面并且显示这种新的成像平面。 操作者还可以选择性地操纵感兴趣的结构的图像上的成像平面。 操作者使用与输入设备结合的图形用户界面和用于在感兴趣的结构上产生成像平面的显示屏幕。 这种图形用户界面被称为三点工具。
-
10.发明授权
公开(公告)号：US5307812A
公开(公告)日：1994-05-03
申请号：US38204
申请日：1993-03-26
IPC分类号： G01R33/20 , A61B5/055 , A61B18/00 , A61B18/20 , A61B18/24 , A61B19/00 , A61N7/00 , A61N7/02 , G01R33/48 , G01R33/561
CPC分类号： A61N7/02 , A61B18/24 , G01R33/4804 , G01R33/561 , A61B2090/374 , G01R33/56308
摘要： Surgery is performed with a pulsed heat-producing device that selectively heats a region in a specific tissue within a patient destroying the tissue. The pulsed heat-producing device may be a coherent optical source that is guided by laser fiber to the tissue to be destroyed. In another embodiment, the pulsed heat-producing device is a focussed ultrasound transducer which concentrates ultrasonic energy at a focal point within the specific tissue. A magnetic resonance imaging system employing a real-time temperature-sensitive pulse sequence monitors the heated region of the tissue to provide temperature profiles allowing an operator to alter the position and size of the heated region.
摘要翻译： 使用脉冲发热装置进行手术，该装置选择性地加热破坏组织的患者内的特定组织中的区域。 脉冲发热装置可以是由激光纤维引导到要破坏的组织的相干光源。 在另一个实施例中，脉冲发热装置是聚焦的超声换能器，其将超声能量集中在特定组织内的焦点处。 使用实时温度敏感脉冲序列的磁共振成像系统监测组织的加热区域以提供温度分布，允许操作者改变加热区域的位置和尺寸。
-
-
-
-
-
-
-
-
-
搜索结果
24 条记录 (耗时 0.019 秒)
