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1.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：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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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：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：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：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：US4472683A
公开(公告)日：1984-09-18
申请号：US420303
申请日：1982-09-20
CPC分类号： G01R33/4833
摘要： An imaging apparatus using nuclear magnetic resonance is disclosed in which both an image corresponding to the projection of a nuclear spin distribution in a to-be-inspected object on a two-dimensional plane and a display mark indicating a desired measuring position are displayed on a display face of a display device such as a CRT display, the display mark is freely moved on the display face to be set at a desired position on the display face, and magnetic field generating means for generating a static magnetic field, linear gradient field, or radio frequency magnetic field is controlled on the basis of the desired position of the display mark to obtain an image of that cross section of the object which is located at a position indicated by the display mark.
摘要翻译： 公开了一种使用核磁共振的成像装置，其中在二维平面上的被检查物体中的核自旋分布的投影和指示期望的测量位置的显示标记的图像都显示在 CRT显示器等显示装置的显示面，在显示面上自由移动显示标记，将其设定在显示面上的期望位置，产生静磁场，线性梯度场， 或者基于显示标记的期望位置来控制射频磁场，以获得位于由显示标记指示的位置处的对象的该横截面的图像。
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公开(公告)号：US4558425A
公开(公告)日：1985-12-10
申请号：US413821
申请日：1982-09-01
IPC分类号： A61B10/00 , A61B5/055 , A61B5/107 , G01R33/28 , G01R33/38 , G01R33/48 , G01R33/58 , G01N15/00
CPC分类号： G01R33/381 , A61B5/1077 , G01R33/28 , G01R33/58
摘要： In an imaging apparatus using nuclear magnetic resonance which includes apparatus for generating a static magnetic field, a linear gradient magnetic field and a radio frequency magnetic field, respectively, signal detection device for detecting the nuclear magnetic resonant signal from an object to be inspected, a computer for calculating from the detection signal an image and output device for displaying the result of calculation by the computer, the improvement wherein the size of the object to be inspected is detected by use of ultrasonic wave or light beams and a signal indicative of the detected size of the object is applied to the linear gradient magnetic field generation apparatus so as to control the intensity of the linear gradient magnetic field.
摘要翻译： 在使用核磁共振的成像装置中，分别包括用于产生静磁场的装置，线性梯度磁场和射频磁场，用于检测来自被检体的核磁共振信号的信号检测装置， 用于从检测信号计算用于显示计算机的计算结果的图像和输出装置的计算机，其中通过使用超声波或光束来检测要检查的对象的大小，以及指示检测到的信号的信号 物体的大小被施加到线性梯度磁场产生装置，以便控制线性梯度磁场的强度。
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公开(公告)号：US4485480A
公开(公告)日：1984-11-27
申请号：US366781
申请日：1982-04-08
CPC分类号： A61B6/4476 , H05G1/60
摘要： A radiation-image photographing apparatus comprises a radiation source, a radiation detector disposed in opposition to the radiation source for detecting radiation through an object to be examined and to generate an electrical signal proportional to the amount of incident radiation, a scanning device for changing the relative, positional relationship between the radiation source and the radiation detector, an analog-to-digital converter for converting the output signal from the radiation detector to a digital quantity, a memory for storing the digital signal, an arithmetic unit, and a display unit. A plurality of measurements of a two-dimensional radiation absorption distribution of the object disposed between the radiation source and the radiation detector is obtained while the relative positional relationship between the radiation source and the radiation detector is being changed, and a linear arithmetic operation is performed on the plurality of image measurements, or a set of data passing a point within the object to be photographed, thereby displaying a cross-sectional image on a given cross-section approximately parallel to the radiation detector plane within the object to be examined.
摘要翻译： 辐射图像拍摄装置包括辐射源，与辐射源相对设置的放射线检测器，用于检测通过待检查物体的辐射并产生与入射辐射量成比例的电信号;扫描装置，用于改变 辐射源和辐射检测器之间的相对位置关系，用于将来自辐射检测器的输出信号转换为数字量的模拟 - 数字转换器，用于存储数字信号的存储器，运算单元和显示单元 。 在辐射源和辐射检测器之间的相对位置关系正在改变的同时，获得放置在辐射源和放射线检测器之间的物体的二维辐射吸收分布的多个测量值，并进行线性算术运算 或多个图像测量中的一组数据，或者通过要拍摄的对象内的点的一组数据，从而在与被检查对象内的放射线检测器平面近似平行的给定横截面上显示横截面图像。
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