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公开(公告)号：US5207222A
公开(公告)日：1993-05-04
申请号：US713316
申请日：1991-06-11
CPC分类号： G01R33/4804
摘要： Based on the relation that the higher the temperature of a portion to be measured, the lower becomes coherence of a nuclear spin at that portion, the present invention measures indirectly the temperature state of the portion to be measured from the change of intensity of NMR signals by utilizing this relationship. A transverse relaxation time is contained as one of the parameters in the relation between the signal intensity and the temperature; hence this transverse relaxation time is determined in advance for the portion to be measured and utilized in for the equation representing their relationship. This application discloses also an invention for determining a blood perfusion rate of the portion to be measured from the temperature data obtained in the manner described above.
摘要翻译： 基于测量部分的温度越高，该部分的核自旋的相关性越低，本发明根据NMR信号的强度的变化间接地测量待测部分的温度状态 通过利用这种关系。 横向弛豫时间作为信号强度与温度之间关系的参数之一; 因此该横向弛豫时间预先被测量的部分用于表示它们的关系的方程式。 本申请还公开了根据以上述方式获得的温度数据来确定待测量部分的血液灌注速率的发明。
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公开(公告)号：USRE34495E
公开(公告)日：1994-01-04
申请号：US725514
申请日：1991-07-03
申请人： Koichi Sano , Tetsuo Yokoyama , Ryuzaburo Takeda , Yasuhiko Ozawa , Shinichi Sato , Hideaki Koizumi
发明人： Koichi Sano , Tetsuo Yokoyama , Ryuzaburo Takeda , Yasuhiko Ozawa , Shinichi Sato , Hideaki Koizumi
IPC分类号： G01F1/716 , G01P5/00 , G01R33/563 , A61B5/055
CPC分类号： G01F1/716 , G01P5/00 , G01R33/56308 , G01R33/56316
摘要： A slice selection gradient magnetic field used in a pulse sequence for generating a spin echo signal is applied in such a fashion that its polarity at the time of a 90.degree. pulse becomes opposite to the one at the time of 180.degree. pulse, in order to expand a dynamic range of blood flow speed measurement. When the blood flow speed contains a component in a slice vertical direction, the gradient magnetic field in the slice vertical direction is adjusted so that the phase changes of two sets of flow encoded pulses contained in the slice vertical direction are opposite to each other.The flow speed in the direction of the readout gradient magnetic field, which is a lateral direction of the slice plane, is purely measured by canceling influences of the flow in the slice vertical direction.
摘要翻译： 施加用于产生自旋回波信号的脉冲序列中的切片选择梯度磁场，使得其在90度脉冲时的极性与180度脉冲时的极性相反，以便 扩大血流速度测量的动态范围。 当血流速度包含切片垂直方向上的分量时，调整切片垂直方向上的梯度磁场，使得包含在切片垂直方向上的两组流动编码脉冲的相位变化彼此相反。 通过消除切片垂直方向上的流动的影响，纯粹地测量作为切片平面的横向的读出梯度磁场的方向上的流速。
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公开(公告)号：US5277182A
公开(公告)日：1994-01-11
申请号：US723692
申请日：1991-06-24
申请人： Hideaki Koizumi , Ryuzaburo Takeda , Hideki Kohno , Tetsuo Yokoyama , Yoshiyuki Miyamoto , Koichi Sano
发明人： Hideaki Koizumi , Ryuzaburo Takeda , Hideki Kohno , Tetsuo Yokoyama , Yoshiyuki Miyamoto , Koichi Sano
IPC分类号： A61B5/055 , G01R33/563
CPC分类号： A61B5/055 , G01R33/563
摘要： A method for imaging the coronary artery of a living body using nuclear magnetic resonance, wherein a patient is located in a static magneic field and the heart cycle of the patient is detected with the heart dilation period of the patient being determined in accordance with the detected heart cycle. Then, the coronary artery of the patient is portrayed on the nuclear magnetic resonance signal generated by applying high-frequency energy to the patient during the determined heart dilation period.
摘要翻译： 一种使用核磁共振对活体的冠状动脉成像的方法，其中患者位于静态磁场中，并且根据检测到的患者的心脏扩张周期被确定，患者的心脏周期被检测到 心脏周期。 然后，在确定的心脏扩张期间，将患者的冠状动脉描绘在通过对患者施加高频能量而产生的核磁共振信号上。
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公开(公告)号：US5016637A
公开(公告)日：1991-05-21
申请号：US356418
申请日：1989-05-25
IPC分类号： A61B10/00 , A61B5/055 , G01R33/48 , G01R33/563 , G01R33/567
CPC分类号： G01R33/5673 , G01R33/563
摘要： An MRI method is disclosed, by which, when liquid moving in a body to be examined stays in a predetermined region, this region is excited by using the nuclear magnetic resonance phenomenon and when the liquid thus excited moves from that excited region, a nuclear magnetic resonance signal produced by the excited spin and emitted during the relaxation time thereof is detected.
摘要翻译： 公开了一种MRI方法，通过该方法，当待检查的体内移动的液体停留在预定区域时，通过使用核磁共振现象来激发该区域，并且当该激发的液体从该激发区域移动时， 检测在其弛豫时间期间由激发的自旋产生并发射的共振信号。
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公开(公告)号：US4844077A
公开(公告)日：1989-07-04
申请号：US170695
申请日：1988-03-14
申请人： Koichi Sano , Tetsuo Yokoyama , Ryuzaburo Takeda , Yasuhiko Ozawa , Shinichi Sato , Hideaki Koizumi
发明人： Koichi Sano , Tetsuo Yokoyama , Ryuzaburo Takeda , Yasuhiko Ozawa , Shinichi Sato , Hideaki Koizumi
IPC分类号： G01F1/716 , G01R33/563
CPC分类号： G01F1/716 , G01R33/56308 , G01R33/56316
摘要： A slice selection gradient magnetic field used in a pulse sequence for generating a spin echo signal is applied in such a fashion that its polarity at the time of a 90.degree. pulse becomes opposite to the one at the time of 180 .degree. pulse, in order to expand a dynamic range of blood flow speed measurement. When the blood flow speed contains a component in a slice vertical direction, the gradient magnetic field in the slice vertical direction is adjusted so that the phase changes of two sets of flow encoded pulses contained in the slice vertical direction are opposite to each other.The flow speed in the direction of the readout gradient magnetic field, which is a lateral direction of the slice plane, is purely measured by cancelling influences of the flow in the slice vertical direction.
摘要翻译： 施加用于产生自旋回波信号的脉冲序列中的切片选择梯度磁场，使得其在90度脉冲时的极性与180度脉冲时的极性相反，以便 扩大血流速度测量的动态范围。 当血流速度包含切片垂直方向上的分量时，调整切片垂直方向上的梯度磁场，使得包含在切片垂直方向上的两组流动编码脉冲的相位变化彼此相反。 通过消除切片垂直方向上的流动的影响，纯粹地测量作为切片平面的横向的读出梯度磁场的方向上的流速。
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公开(公告)号：US4736160A
公开(公告)日：1988-04-05
申请号：US867541
申请日：1986-05-28
申请人： Koichi Sano , Shimbu Yamagata , Koichi Haruna , Hideaki Koizumi , Shinichi Sato , Tetsuo Yokoyama , Ryuzaburo Takeda
发明人： Koichi Sano , Shimbu Yamagata , Koichi Haruna , Hideaki Koizumi , Shinichi Sato , Tetsuo Yokoyama , Ryuzaburo Takeda
IPC分类号： G01R33/54 , G01R33/565 , G01R33/20
CPC分类号： G01R33/565 , G01R33/54 , G01R33/56563
摘要： In order to make an accurate display possible even in case image data having been subjected to a Fourier transformation have negative values, the sampling timing deviations of measured signals having phase errors based on various factors are detected from the gradient of the linear components of the image data having been subjected to the Fourier transformation, and the density values of the image having the detected timing deviations corrected are displayed.
摘要翻译： 为了即使在已经进行了傅立叶变换的图像数据的情况下，即使在具有负值的情况下也可以进行准确的显示，根据图像的线性分量的梯度来检测具有基于各种因素的相位误差的测量信号的采样定时偏差 已经进行傅里叶变换的数据，并且显示校正了检测到的定时偏差的图像的浓度值。
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公开(公告)号：US5023553A
公开(公告)日：1991-06-11
申请号：US330835
申请日：1989-03-30
申请人： Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
发明人： Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
CPC分类号： G01R33/5676
摘要： In order to eliminate the degradation of NMR image caused by a body motion due to breathing or the like, one of measured image signals is selected as a reference, correlation is calculated between each measured image signal and the reference, and the image signal is modified on the basis of the value of correlation.
摘要翻译： 为了消除由于呼吸等引起的身体运动引起的NMR图像的劣化，选择测量图像信号之一作为参考，在每个测量的图像信号和参考之间计算相关性，并且图像信号被修改 在相关性的基础上。
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公开(公告)号：US4939462A
公开(公告)日：1990-07-03
申请号：US376216
申请日：1989-07-03
申请人： Akira Maeda , Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
发明人： Akira Maeda , Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
CPC分类号： G01R33/4833
摘要： In order to narrow the dynamic range of an NMR signal and to provide MRI of low cost and high image quality without inducing the distortions of an image other than distortion of phase which can be corrected or the degradations of the measurement accuracies of various parameters, a coil for generating an inhomogeneous magnetic field which varies slowly within region to-be-imaged is added to a coil for generating a static magnetic field of high homogeneity, and current to flow through the former coil is changed so as to control the inhomogeneous magnetic field.
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公开(公告)号：US4724388A
公开(公告)日：1988-02-09
申请号：US869976
申请日：1986-06-02
申请人： Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
发明人： Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
IPC分类号： G01R33/565 , G01R33/20
CPC分类号： G01R33/56518 , G01R33/56563
摘要： In order to measure a static field distribution with one scanning operation and to make image distortion corrections with the static field distribution and a gradient field distribution simultaneously considered, an image is reconstructed using a spin echo signal produced under the condition that a time interval between a 90.degree. pulse and a 180.degree. pulse differs from an interval between the 180.degree. pulse and the time origin of the spin echo signal, the static field distribution is evaluated from the relation of distortions to phase errors free from a phase distortion attributed to the characteristic of a detecting part and a phase distortion attributed to the dynamic characteristic of the gradient field, a relations existing between the spatial distortion and phase distortion of the reconstructed image and a magnetic field distribution including the gradient field is obtained, and the distortion magnitude of the reconstructed image is evaluated from the measured magnetic field distribution.
摘要翻译： 为了通过一次扫描操作测量静态场分布，并且同时考虑静态场分布和梯度场分布进行图像失真校正，使用自旋回波信号来重构图像，该自旋回波信号是在 90°脉冲和180°脉冲与180°脉冲与自旋回波信号的时间原点之间的间隔不同，静态场分布从失真和相位误差的关系来评估，该相位误差不包括归因于特性的相位失真 得到归因于梯度场的动态特性的检测部分和相位失真，获得重建图像的空间失真和相位失真之间存在的关系以及包括梯度场的磁场分布，并且， 从测量的磁场分布评估重建图像 。
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公开(公告)号：US4905699A
公开(公告)日：1990-03-06
申请号：US92303
申请日：1987-09-02
申请人： Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
发明人： Koichi Sano , Tetsuo Yokoyama , Hideaki Koizumi
IPC分类号： A61B5/055
CPC分类号： A61B5/055 , A61B5/7257
摘要： In order to permit the detection of a respiratory motion and an imaging synchronized with the respiration by an NMR imaging apparatus itself without any special hardware, a sequence for detecting the respiratory motion is repeated for a short time immediately before the measurement of an image signal to detect the position and speed of the respiratory motion, and a desired image signal is measured in synchronism with the detected position. Alternatively, the respiratory motion is detected immediately after the measurement of an image signal, and the measured image signal is corrected in accordance with the detected amount to obtain a desired image signal synchronized with the respiration.
摘要翻译： 为了允许通过NMR成像设备本身检测呼吸运动和与呼吸同步的成像，而没有任何特殊的硬件，用于检测呼吸运动的顺序在测量图像信号之前的短时间内被重复到 检测呼吸运动的位置和速度，并且与检测到的位置同步地测量期望的图像信号。 或者，在测量图像信号之后立即检测呼吸运动，并且根据检测到的量校正测量的图像信号，以获得与呼吸同步的期望的图像信号。
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