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公开(公告)号：US4716369A
公开(公告)日：1987-12-29
申请号：US746663
申请日：1985-06-20
IPC分类号： G01R33/485 , G01R33/561 , G01R33/20
CPC分类号： G01R33/485 , G01R33/5615 , G01R33/5616
摘要： The present invention is an imaging method using three-dimensional NMR to which an echo-planar method is applied. After excitation of nuclear spins, the gradient magnetic field Gx for phase-encoding is applied and there is repeated a sequence of measuring and obtaining an echo train of spin-echoes with a constant gradient magnetic field Gx and a periodically-inverted gradient magnetic field Gy, as varying the amount of encoding, so as to obtain the three-dimensional imaging by the Fourier-conversion. Moreover, after the selective excitation of spins within an X-Y surface, a 180.degree. radio frequency pulse is applied. As varying the time difference .tau..sub..epsilon. between the interval from the excitation until the application of the 180.degree. radio frequency pulse and the interval from the application thereof until a peak of a first echo of an echo train, three-dimensional imaging is carried out with a chemical shift axis as one axis by repeating the sequence and accomplishing Fourier-conversion with .tau..sub..epsilon. as a numerical variable.
摘要翻译： 本发明是使用采用回波平面法的三维NMR的成像方法。 在激励核自旋之后，施加用于相位编码的梯度磁场Gx，并且重复测量并获得具有恒定梯度磁场Gx和周期性反转梯度磁场Gy的自旋回波回波序列的序列 ，因为改变编码量，从而通过傅里叶变换获得三维成像。 此外，在X-Y表面中的自旋选择性激发之后，施加180°射频脉冲。 随着从激励到施加180°射频脉冲的间隔与从应用到应用的间隔直到回波列的第一回波的峰值之间的时间差τεε改变，三维成像是 化学位移轴作为一个轴，通过重复该序列，并以tauε作为数值变量进行傅里叶变换。
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公开(公告)号：US4797616A
公开(公告)日：1989-01-10
申请号：US151901
申请日：1988-02-03
CPC分类号： G01R33/485
摘要： An NMR spectroscopic imaging method of obtaining separate spin distribution images for respective spectral components of the spectrum of an NMR signal caused by the chemical shift of nuclides of interest in an object includes providing for a transversal magnetization signal of the object placed in a static magnetic field. A position of the signal in a phase domain is translated in a K-space from the origin thereof. Further, the signal is sampled while rotating a position of the signal in the K-space plural times on a certain circle in the K-space by applying a rotating field gradient, thereby to obtain a group of signal data. Signal data trains each of which is composed of signal data present at the same position on the K-space in the signal data group obtained by the sampling during the plural signal rotations, is subjected to Fourier transformations, respectively, thereby effecting a spectral analysis of the NMR signal.
摘要翻译： 由对象物质的化学位移引起的核磁共振信号频谱的各频谱分量的分离自旋分布图像的NMR分光成像方法包括提供放置在静磁场中的物体的横向磁化信号 。 信号在相位域中的位置从其原点在K空间中平移。 此外，在通过施加旋转场梯度在K空间中的某个圆上多次旋转K空间中的信号的位置的同时对信号进行采样，从而获得一组信号数据。 由多个信号旋转中的采样获得的信号数据组中的与K空间上的相同位置处的信号数据组成的信号数据串分别进行傅里叶变换，从而进行频谱分析 NMR信号。
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公开(公告)号：US4689568A
公开(公告)日：1987-08-25
申请号：US750475
申请日：1985-07-01
IPC分类号： G01R33/44 , A61B5/055 , A61B10/00 , G01R33/48 , G01R33/485 , G01R33/561 , G01R33/20
CPC分类号： G01R33/485 , G01R33/5616
摘要： An NMR imaging method which provides a three-dimensional image representative of the two-dimensional distribution of nuclear spin species resolved by chemical shift or the local spectra resolved by two-dimensional location. After the excitation of nuclear spins and the phase-encoding by application of a field gradient G.sub.y, a periodically inverting field gradient G.sub.x is generated to yield a continuous echo train. The echo train is sampled and separated into data of odd-numbered echoes and data of even-numbered echoes which data are in turn reconstructed into two-dimensional data arrays, respectively. The data thus reconstructed are three-dimensional Fourier-transformed.
摘要翻译： 提供表示通过化学位移分解的核自旋物质的二维分布的三维图像的NMR成像方法或通过二维位置解析的局部光谱。 在核自旋的激励和通过施加场梯度Gy的相位编码之后，产生周期性反转场梯度Gx以产生连续的回波串。 回波串被采样并分离成奇数回波的数据和偶数回波的数据，数据又分别被重建成二维数据阵列。 这样重建的数据是三维傅里叶变换的。
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4.发明授权Method of measuring the static magnetic field distribution in an NMR inspection system 失效在NMR检查系统中测量静态磁场分布的方法
公开(公告)号：US4672318A
公开(公告)日：1987-06-09
申请号：US696909
申请日：1985-01-31
CPC分类号： G01R33/24
摘要： A method of measuring a static magnetic field distribution in a nuclear magnetic resonance (NMR) inspection system which comprises magnetic field generator for producing a static magnetic field, inclination or gradient magnetic fields and a high-frequency magnetic field, a signal detector for sensing nuclear magnetic resonance signals from an inspection sample, a computer for processing output signals from the signal detector and an output device for providing a computational result of the computer, wherein a time interval t.sub.1 from the center of a 90.degree.-pulse high-frequency magnetic field to the center of a 180.degree.-pulse high-frequency magnetic field is made different by a time difference t.sub.0 from a time interval t.sub.2 from the center of the 180.degree.-pulse high-frequency magnetic field to a peak of a spin echo, so that static magnetic field distribution is calculated based on the computer output which corresponds to the difference of the two time intervals.
摘要翻译： 一种在核磁共振（NMR）检查系统中测量静磁场分布的方法，其包括用于产生静磁场，倾斜或梯度磁场和高频磁场的磁场发生器，用于感测核的信号检测器 来自检查样本的磁共振信号，用于处理来自信号检测器的输出信号的计算机和用于提供计算机的计算结果的输出装置，其中从90°脉冲高频磁场的中心起的时间间隔t1 从180°脉冲高频磁场的中心到从180°脉冲高频磁场的中心到自旋回波的峰值的时间间隔t2由时间差t0变化到180°脉冲高频磁场的中心，因此 基于对应于两个时间间隔的差的计算机输出来计算静态磁场分布。
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公开(公告)号：US4683433A
公开(公告)日：1987-07-28
申请号：US636995
申请日：1984-08-02
申请人： Etsuji Yamamoto , Hideki Kohno , Masao Kuroda , Shigeru Matsui , Hidemi Shiono
发明人： Etsuji Yamamoto , Hideki Kohno , Masao Kuroda , Shigeru Matsui , Hidemi Shiono
CPC分类号： G01R33/482 , G01R33/56
摘要： An NMR imaging apparatus and method for detecting a nuclear spin resonance signal from an object, which is placed in a magnetic field, to produce images of the object. At an instant when the spins come into phase after the signal detection by a first spin excitation, RF magnetic field pulses are applied for rotating the direction of the spin to that opposite to the initial state. After that, the spin excitation and the signal direction of second time are conducted to measure the data which are different in the effect of the relaxation time from the first measurements. By repeating these sequences, it is possible to produce a plurality of images such as an intensity image or a relaxation time enhanced image.
摘要翻译： 一种用于检测放置在磁场中的物体的核自旋共振信号的NMR成像设备和方法，以产生物体的图像。 在通过第一自旋激发在信号检测之后自旋进入相位的瞬间，施加RF磁场脉冲以将旋转方向旋转到与初始状态相反的方向。 之后，进行自旋激励和第二次的信号方向，以测量与第一次测量相比，松弛时间的影响不同的数据。 通过重复这些序列，可以产生多个图像，例如强度图像或弛豫时间增强图像。
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公开(公告)号：US4939463A
公开(公告)日：1990-07-03
申请号：US218694
申请日：1988-07-07
申请人： Kensuke Sekihara , Shigeru Matsui , Hideki Kohno
发明人： Kensuke Sekihara , Shigeru Matsui , Hideki Kohno
CPC分类号： G01R33/56554 , G01R33/56
摘要： A method wherein the requirement for the amplitude of the oscillating gradient magnetic field is relaxed by reconstructing an image while using simultaneously echoes S.sub.p (k.sub.x, y) produced in the case where the positive oscillating gradient magnetic field is applied to the object to be tested and echoes S.sub.N (k.sub.x, y) produced in the case where the negative is applied thereto, i.e. by using data points on segments of a trajectory of data points ascending from left to right in the spatial frequency domain and those on segments of a trajectory of data points ascending from right to left. That is, the image M(x, y) is obtained by Fourier-transforming at first the echoes S.sub.p (k.sub.x, k.sub.y) and S.sub.N (k.sub.x, k.sub.y) with respect to k.sub.y, multiplying complex numbers a.sub.1 and a.sub.2 to g.sub.p (k.sub.x, y) and g.sub.N (k.sub.x, y) obtained by this transformation; adding the results thus obtained, i.e. forming g(k.sub.x, y)=a.sub.1 g.sub.p (k.sub.x, y)+a.sub.2 g.sub.N (k.sub.x, y); and finally Fourier-transforming this g(k.sub.x, y) with respect to k.sub.x.
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公开(公告)号：US4733188A
公开(公告)日：1988-03-22
申请号：US850113
申请日：1986-04-10
申请人： Kensuke Sekihara , Shigeru Matsui , Hideki Kohno
发明人： Kensuke Sekihara , Shigeru Matsui , Hideki Kohno
IPC分类号： A61B10/00 , A61B5/055 , G01R33/48 , G01R33/561 , G01R33/20
CPC分类号： G01R33/5615 , G01R33/5616
摘要： In imaging methods represented by the echo-planar method, i.e., in a method including a step of measuring the spin echos while applying a fixed gradient magnetic field to an object and applying a gradient field G.sub.Y periodically inverted in sense to the object and a step of obtaining the spin distribution image in the spatial domain by applying two-dimensional Fourier transform to the measured data, measurement is repeated a plurality of times while altering the phase of the applied waveform of G.sub.X, and the spin density image is derived by applying two-dimensional Fourier transform to a plurality of sets of data groups thus obtained.
摘要翻译： 在由回波平面方法表示的成像方法中，即在包括测量自旋回波的步骤的方法中，同时向对象施加固定的梯度磁场，并且向对象施加周期性反转的渐变场GY，并且步骤 通过对测量数据应用二维傅里叶变换获得空间域中的自旋分布图像，在改变GX的施加波形的相位的同时重复测量多次，并且通过应用两个方法导出自旋密度图像 维数傅里叶变换到由此获得的多组数据组。
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公开(公告)号：US4727325A
公开(公告)日：1988-02-23
申请号：US919767
申请日：1986-10-16
申请人： Shigeru Matsui , Kensuke Sekihara , Hideki Kohno
发明人： Shigeru Matsui , Kensuke Sekihara , Hideki Kohno
IPC分类号： G01R33/54 , G01R33/561 , G01R33/20
CPC分类号： G01R33/54 , G01R33/5615 , G01R33/5616
摘要： An NMR imaging method using a rotating field gradient is disclosed in which transverse magnetization is prepared in a portion of an object to be inspected, by the 90.degree.-180.degree. RF pulse excitation, a rotating field gradient is generated to perform a sampling operation for an output signal in a state that the position of signal in a phase space is revolved, the intensity or rotational speed of the rotating field gradient is varied stepwise or continuously to obtain data arranged on concentric circles or a spiral in the phase space, and the data thus obtained undergoes Fourier transformation in each of a plurality of radial directions or two-dimensional Fourier transformation, to form an image of spin distribution.
摘要翻译： 公开了使用旋转磁场梯度的NMR成像方法，其中通过90°-180°RF脉冲激励在待测物体的一部分中制备横向磁化，产生旋转场梯度以执行采样操作 在相位空间中的信号的位置旋转的状态下的输出信号，旋转场梯度的强度或旋转速度逐步或连续地变化，以获得布置在相空间中的同心圆或螺旋上的数据，并且 由此获得的数据在多个径向方向或二维傅里叶变换中进行傅里叶变换，以形成自旋分布的图像。
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公开(公告)号：US4777443A
公开(公告)日：1988-10-11
申请号：US119489
申请日：1987-11-12
申请人： Masao Yabusaki , Etsuji Yamamoto , Takashi Onodera , Yukiko Ogura , Hideaki Nakane , Shigeru Matsui , Hideki Kohno
发明人： Masao Yabusaki , Etsuji Yamamoto , Takashi Onodera , Yukiko Ogura , Hideaki Nakane , Shigeru Matsui , Hideki Kohno
IPC分类号： G01R33/035 , G01R33/36 , G01R33/20
CPC分类号： G01R33/326 , G01R33/0358
摘要： Disclosed in a nuclear magnetic resonance (NMR) based inspection apparatus using an SQUID flux meter for detecting a small NMR signal, in which a receiving coil for receiving the NMR signal from an object is connected to a mixer, which mixes a reference high-frequency signal with the NMR signal so that the NMR signal is reduced to a low-frequency signal having a differential component of frequencies of both signals, and the low-frequency signal is applied to the input coil of the SQUID flux meter so that it is converted into a voltage signal. The mixer circuit includes Schottky diodes operative at a liquid helium temperature or Josephson junctions, and the portions of apparatus from the reception coil up to the SQUID flux meter are operated in a superconductive state at a liquid helium temperature.
摘要翻译： 在使用SQUID通量计检测小型NMR信号的基于核磁共振（NMR）的检查装置中公开了一种用于从物体接收NMR信号的接收线圈连接到混频器，该混频器将参考高频 用NMR信号进行信号，使得NMR信号被减少到具有两个信号的频率的差分分量的低频信号，并且低频信号被施加到SQUID通量计的输入线圈，使得其被转换 变成电压信号。 混频器电路包括以液氦温度或约瑟夫逊结操作的肖特基二极管，并且从接收线圈到SQUID通量计的装置部分在液氦温度下处于超导状态。
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公开(公告)号：US4625170A
公开(公告)日：1986-11-25
申请号：US635154
申请日：1984-07-27
申请人： Etsuji Yamamoto , Shigeru Matsui , Masuo Kuroda , Hideki Kohno
发明人： Etsuji Yamamoto , Shigeru Matsui , Masuo Kuroda , Hideki Kohno
IPC分类号： G01R33/20 , A61B5/055 , A61B10/00 , G01R33/48 , G01R33/565
CPC分类号： G01R33/56518
摘要： An NMR imaging method and apparatus of the type in which a 180-degree RF pulse is applied to generate a spin echo after the selective excitation of a spin by a 90-degree RF pulse. A dummy gradient field, which has the same direction and intensity as those of a gradient field to be applied when the spin echo is observed, is applied between said 90-degree RF pulse and said 180-degree RF pulse so that the instant of starting the application of the gradient field for signal observation is advanced to the extent corresponding to said dummy gradient field.
摘要翻译： 一种NMR成像方法和装置，其中施加180度RF脉冲以在旋转选择性激发90度RF脉冲之后产生自旋回波。 在所述90度RF脉冲和所述180度RF脉冲之间，施加与观察到自旋回波时要施加的梯度场相同的方向和强度的虚拟梯度场，使得起始时刻 将用于信号观察的梯度场的应用提前到对应于所述虚拟梯度场的程度。
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