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公开(公告)号：US4760339A
公开(公告)日：1988-07-26
申请号：US944001
申请日：1986-12-22
申请人： Etsuji Yamamoto , Koichi Sano , Hidemi Shiono , Hideki Kohno
发明人： Etsuji Yamamoto , Koichi Sano , Hidemi Shiono , Hideki Kohno
IPC分类号： A61B10/00 , A61B5/055 , G01R33/48 , G01R33/485 , G01R33/565 , G01R33/20
CPC分类号： G01R33/565 , G01R33/485 , G01R33/56527
摘要： An NMR imaging method is disclosed in which an object is measured in accordance with a pulse sequence capable of expressing a difference between two of a plurality of chemical shifts by a phase difference in a signal, that is, a pulse sequence 90.degree.-.tau..sub.a -180.degree.-.tau..sub.b -spin echo (where .tau..sub.a .noteq..tau..sub.b) to obtain spin distribution data, a histogram with respect to the phase of the spin distribution data is formed to regard a phase corresponding to that one of a plurality of peaks of the histogram which exists at one end of the histogram, as a position-independent offset phase which is contained in the spin distribution data and is peculiar to an NMR imaging apparatus, and the spin distribution data is corrected using the offset value thus obtained, to extract spin density distribution data for each of the chemical shifts from the corrected spin distribution data.
摘要翻译： 公开了一种NMR成像方法，其中根据能够通过信号的相位差表示多个化学位移之间的差异的脉冲序列来测量物体，即脉冲序列90°-τa -180°-τb-自旋回波（其中τa NOTEQUAL tau b）为了获得自旋分布数据，形成相对于自旋分布数据的相位的直方图，以考虑与多个峰中的那一个相对应的相位 存在于直方图的一端的直方图作为自旋分布数据中包含的并且是NMR成像设备特有的与位置无关的偏移相位，并且使用由此获得的偏移值来校正自旋分布数据， 从校正的自旋分布数据中提取每个化学位移的自旋密度分布数据。
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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：US4739265A
公开(公告)日：1988-04-19
申请号：US846151
申请日：1986-03-31
申请人： Etsuji Yamamoto , Kensuke Sekihara , Hidemi Shiono , Hideki Kohno
发明人： Etsuji Yamamoto , Kensuke Sekihara , Hidemi Shiono , Hideki Kohno
IPC分类号： G01R33/485 , G01R33/565 , G01R33/20
CPC分类号： G01R33/565 , G01R33/485 , G01R33/56527
摘要： A method for providing spin density distribution images of an object, discriminated with respect to plural chemical shifts. This method is performed by repeating a measurement sequence in a spin warp imaging method, of the spin data plural times, with a time difference .DELTA..tau. between a time interval .tau..sub.1 from spin excitation to a 180.degree. RF pulse and a time interval .tau..sub.2 from the 180.degree. RF pulse to a peak of a spin echo, altering .DELTA..tau. in the ways corresponding the number of chemical shifts to be discriminated from one another, subjecting the respective spin data to two-dimensional Fourier transform to provide plural sets of spin data for respective coordinates in a spatial domain, and solving simultaneous equations of the sets of spin data to provide spin densities corresponding to the respective chemical shifts.
摘要翻译： 一种用于提供对象的自旋密度分布图像的方法，其被鉴别为多个化学位移。 该方法通过在旋转数据成像方法中重复自旋数据多次的测量序列，其中从自旋激发到180°RF脉冲的时间间隔τ1与时间间隔τ2之间的时间差DELTAτ 从180°RF脉冲到自旋回波的峰值，以相应于要彼此区分的化学位移数的方式改变DELTA tau，对各自旋转数据进行二维傅里叶变换以提供多组旋转 用于空间域中的各个坐标的数据，以及求解自旋数据组的联立方程以提供对应于各个化学位移的自旋密度。
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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：US5394872A
公开(公告)日：1995-03-07
申请号：US44778
申请日：1993-04-12
IPC分类号： A61B5/055 , G01R33/48 , G01R33/561 , G01R33/563 , G01R33/20
CPC分类号： G01R33/563 , G01R33/5618 , G01R33/56333
摘要： In a magnetic resonance imagining method, using an effect that a fluid flows out of a plane where it is selectively excited between the time of applying a 90.degree. radio frequency pulse and the time of applying of a 180.degree. radio frequency pulse, two, images are separately constructed from multiple echo signals which are sampled before applying the 180.degree. radio frequency pulse and multiple echo signals which are sampled after applying the 180.degree. radio frequency pulse. An image of the fluid flow and an image of a static part are separated from each other based on a difference between the two constructed images.
摘要翻译： 在磁共振想象方法中，使用流体从施加90°射频脉冲的时间和施加180°射频脉冲的时间之间选择性激发的平面流出的效果，两个图像 分别由在应用180°射频脉冲之前被采样的多个回波信号和在施加180°射频脉冲之后被采样的多个回波信号构成。 基于两个构造的图像之间的差异，流体流动的图像和静态部分的图像彼此分离。
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公开(公告)号：US5465719A
公开(公告)日：1995-11-14
申请号：US98775
申请日：1993-07-29
CPC分类号： G01R33/385 , G01R33/3802 , G01R33/3854
摘要： A bobbin for holding a gradient magnetic field coil, having a changeable size and sectional shape (a separable bobbin) is constituted by assembling coil supporters (a bobbin divided into a plurality of segments). The separable bobbin has coil supporters of an upper part a bottom part and a set of side surface parts and at least two supporting rods made of a nonmagnetic substance are fitted to the side surface parts of the coil supporters. Holes permitting the insertion of the supporting rods are bored in the upper and bottom parts of the coil supporters. The length d1 between both side surface parts can be made variable by adjusting the insertion length of the supporting rod into the upper and bottom parts. Accordingly, the distance between a patient and a gradient magnetic field can be reduced, and an intended gradient magnetic field intensity can be generated by a smaller current producing the gradient magnetic field than in the prior art. Setting of the patient to an MRI imaging apparatus becomes also easier, and there can be obtained a gradient magnetic field coil capable of being easily fitted and removed to and from the MRI imaging apparatus.
摘要翻译： 用于保持具有可变尺寸和截面形状（分离线圈架）的梯度磁场线圈的线轴由线圈支架（分为多个段的线轴）组装而成。 可分离筒管具有上部的线圈支撑件，底部部分和一组侧面部分，并且至少两个由非磁性物质制成的支撑杆装配到线圈支撑件的侧表面部分。 允许插入支撑杆的孔在线圈支撑件的上部和底部中钻孔。 通过将支撑杆的插入长度调节到上部和底部，两个侧面部分之间的长度d1可以变化。 因此，可以减少患者与梯度磁场之间的距离，并且通过产生梯度磁场的较小电流可以产生预期的梯度磁场强度，而不是现有技术。 将患者设置到MRI成像设备变得更容易，并且可以获得能够容易地装配和去除MRI成像设备的梯度磁场线圈。
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公开(公告)号：US5539311A
公开(公告)日：1996-07-23
申请号：US160807
申请日：1993-12-03
IPC分类号： G01R33/561 , G01V3/00
CPC分类号： G01R33/56554
摘要： In magnetic resonance imaging, a first echo train is obtained by applying a readout gradient magnetic field to a region of interest to be imaged and periodically inverting the polarity of the readout gradient magnetic field, without applying an encoding gradient magnetic field to the region of interest. A periodic change of phase shift of the first echo train is detected from the first echo train. Information indicating phase shifts of all of the echoes in the first echo train is obtained using the periodic change of phase shift. A second echo train is obtained by applying a readout gradient magnetic field and an encoding magnetic field to the region of interest and periodically inverting the polarity of the readout gradient magnetic field. Phases of echoes in the second echo train are corrected using the information indicating phase shifts of all of the echoes in the first echo train.
摘要翻译： 在磁共振成像中，通过将读出梯度磁场施加到要成像的感兴趣区域并周期性地反转读出梯度磁场的极性，而不对感兴趣的区域施加编码梯度磁场，获得第一回波串 。 从第一回波列检测第一回波串的相移的周期性变化。 使用相移的周期性变化来获得指示第一回波列中的所有回波的相移的信息。 通过将读出梯度磁场和编码磁场施加到感兴趣的区域并周期性地反转读出梯度磁场的极性来获得第二回波串。 使用指示第一回波列中的所有回波的相移的信息来校正第二回波列中的回波相位。
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公开(公告)号：US5221898A
公开(公告)日：1993-06-22
申请号：US798907
申请日：1991-11-27
IPC分类号： G01R33/561 , G01R33/563
CPC分类号： G01R33/56308 , G01R33/5616 , G01R33/56316
摘要： This invention relates to a ultra-high speed nuclear magnetic resonance fluid imaging method for selectively reconstructing projected images of a fluid from an echo train generated by the use of a readout gradient magnetic field which inverses periodically. A pulse-like encoding gradient magnetic field is used in combination with a readout gradient magnetic field which inverses periodically, so as to generate an echo train containing alternately echoes whose phase change of magnetization due to a flow is emphasized and echoes whose phase change of magnetization due to the flow is corrected, and subjected sequentially to phase encoding. A data train containing only the echoes whose phase change of magnetization due to the flow is emphasized and a data train containing only the echoes whose phase change of magnetization due to the flow is corrected are formed from sampling data of these echoes, respectively, and two images are then obtained by subjecting them individually to two-dimensional Fourier transform. Both of these images are then subtracted.
摘要翻译： 本发明涉及一种超高速核磁共振流体成像方法，用于从通过使用周期性反转的读出梯度磁场产生的回波序列中选择性地重构流体的投影图像。 脉冲式编码梯度磁场与周期性反转的读出梯度磁场结合使用，以便生成包含交替回波的回波串，该回波串被强调由于流动引起的磁化相位变化，并且回波其磁化相位变化 由于流程被校正，并且顺序地进行相位编码。 仅包含其中由于流动引起的磁化相位变化的回波的数据列被分别由这些回波的采样数据分别形成，并且仅包含校正由流动引起的磁化相位变化的回波的数据列分别形成 然后通过对它们进行二维傅立叶变换而获得图像。 然后将这两个图像相减。
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公开(公告)号：US5493224A
公开(公告)日：1996-02-20
申请号：US25785
申请日：1993-03-03
申请人： Hidemi Shiono , Kenji Takiguchi , Etsuji Yamamoto
发明人： Hidemi Shiono , Kenji Takiguchi , Etsuji Yamamoto
IPC分类号： G01R33/561 , G01V3/00
CPC分类号： G01R33/56554 , G01R33/5616
摘要： A magnetic resonance imaging method and apparatus employing a pulse sequence including a periodically switched readout gradient and a phase encoding gradient to derive a series of echo signals. Prior to execution of the pulse sequence for acquiring data for imaging, a pulse sequence in which the phase encoding gradient is cancelled is executed to obtain information of deviation in position of echo peaks. Thereafter, a pulse sequence including the phase encoding gradient is executed and at this time, sampling start timings for echo data sampling in respective phase periods of the readout gradient are controlled according to the information of the echo peak deviation. Further, a phase difference between data of odd number echo signals and data of even number echo signals is compensated by rotating either of the data of the odd number echo signals or the even number echo signals by a suitable rotating angle to minimize artifacts.
摘要翻译： 一种磁共振成像方法和装置，其采用包括周期性切换读出梯度和相位编码梯度的脉冲序列以导出一系列回波信号。 在执行用于获取用于成像的数据的脉冲序列之前，执行消除相位编码梯度的脉冲序列以获得回波峰位置偏差的信息。 此后，执行包括相位编码梯度的脉冲序列，此时，根据回波峰值偏差的信息来控制读出梯度的各个相位周期中的回波数据采样的采样开始定时。 此外，奇数回波信号的数据和偶数回波信号的数据之间的相位差通过旋转奇数回波信号的数据或偶数回波信号中的适当旋转角来补偿，以最小化伪像。
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公开(公告)号：US5427102A
公开(公告)日：1995-06-27
申请号：US331156
申请日：1994-10-28
申请人： Shin'ichi Shimode , Hiroshi Inouye , Norihide Saho , Shinya Okabe , Masayuki Otsuka , Yukiji Iwase , Etsuji Yamamoto , Hidemi Shiono , Kenji Takiguchi
发明人： Shin'ichi Shimode , Hiroshi Inouye , Norihide Saho , Shinya Okabe , Masayuki Otsuka , Yukiji Iwase , Etsuji Yamamoto , Hidemi Shiono , Kenji Takiguchi
IPC分类号： A61B5/055 , G01N33/38 , G01R33/28 , G01R33/385 , G01R33/54 , G10K11/178 , H04R1/40 , H04R3/00 , H04B15/00
CPC分类号： G01R33/3854 , G10K11/1786 , H04R1/40 , H04R3/00 , G01R33/283 , G01R33/385 , G01R33/543 , G10K2210/1161 , G10K2210/3026 , G10K2210/3027 , Y10S128/925
摘要： An active noise cancellation apparatus of an MRI apparatus, including a detector for detecting vibration of a bobbin or a driving signal of a magnetism generator as a noise source signal, error signal detectors for detecting actual noise near the ears of a patient, a circuit for generating a noise cancellation signal having an opposite phase to a phase of a noise signal generated by an MRI apparatus and having an amplitude proportional to the output of the error signal detectors, from the detected noise source signal and the output of the error signal detectors, and a sound generator for generating a sound wave by the noise cancellation signal.
摘要翻译： 一种MRI装置的主动噪声消除装置，包括用于检测线轴的振动的检测器或作为噪声源信号的磁性发生器的驱动信号，用于检测患者耳部附近的实际噪声的误差信号检测器， 产生噪声消除信号，所述噪声消除信号具有与由MRI装置产生的噪声信号的相位相反的相位，并且具有与所述误差信号检测器的输出成比例的振幅，所述噪声消除信号与所述检测到的噪声源信号和所述误差信号检测器的输出相对应， 以及用于通过噪声消除信号产生声波的声音发生器。
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