公开(公告)号：US5208534A

公开(公告)日：1993-05-04

申请号：US564328

申请日：1990-08-08

申请人： Kazuya Okamoto ,  Kozo Satoh

发明人： Kazuya Okamoto ,  Kozo Satoh

IPC分类号： G01R33/3415 ,  G01R33/54 ,  G01R33/56

CPC分类号： G01R33/3415 ,  G01R33/54 ,  G01R33/56

摘要： A magnetic resonance imaging system includes a magnetic field applying section for applying a static field, gradient field pulses, and an RF field to an object to be examined, a signal detecting section, including a homogeneous coil and a plurality of surface coils arranged to surround a desired region of the object, for detecting magnetic resonance signals from the object through the homogeneous coil and the surface coils, and an image data processing section for obtaining an image of the desired region by synthesizing image data based on the magnetic resonance signals respectively detected by the surface coils upon weighting/adding processing. The system uses differential surface coils as the surface coils. A magnetic resonance signal is detected through the homogeneous coil within the same time interval in which magnetic resonance signals are detected through the surface coils. Weighting functions for weighting/adding processing of image data are determined on the basis of these magnetic resonance signals.

公开(公告)号：US4760338A

公开(公告)日：1988-07-26

申请号：US878783

申请日：1986-06-26

申请人： Katzumi Kose ,  Kozo Satoh

发明人： Katzumi Kose ,  Kozo Satoh

IPC分类号： G01R33/44 ,  A61B5/055 ,  A61B10/00 ,  G01R33/48 ,  G01R33/54 ,  G01R33/20

CPC分类号： G01R33/446 ,  G01R33/482

摘要： In an imaging apparatus and a method for producing a two-dimensional image of an object under medical examination, a composite selective RF pulse is produced in a transmitter unit. The composite selective RF pulse is constituted of a second RF 90.degree. pulse and a third RF 90.degree. pulse. Under the control of a system processor, the second RF 90.degree. pulse is firstly applied to the object and the third RF 90.degree. pulse is secondly applied thereto under the same polarity of the field gradient after providing an time interval.

摘要翻译： 在成像装置和用于在医学检查下产生物体的二维图像的方法中，在发射器单元中产生复合选择性RF脉冲。 复合选择性RF脉冲由第二RF 90°脉冲和第三RF 90°脉冲构成。 在系统处理器的控制下，首先将第二RF 90 DEG脉冲施加到物体，并且在提供时间间隔之后，在场梯度的相同极性下将第三RF 90°脉冲二次施加到其上。

公开(公告)号：US4746864A

公开(公告)日：1988-05-24

申请号：US31461

申请日：1987-03-30

申请人： Kozo Satoh

发明人： Kozo Satoh

IPC分类号： G01R33/44 ,  A61B5/055 ,  A61B10/00 ,  G01R33/48 ,  G01R33/561 ,  G01R33/565 ,  G01R33/20

CPC分类号： G01R33/56563 ,  G01R33/5615 ,  G01R33/5618

摘要： In an MRI system of this invention, a pulsed RF magnetic field, and pulsed slice, phase encoding, and read gradient fields are applied to an object to be examined placed in a uniform static magnetic field in accordance with a predetermined sequence by a controller, thereby causing an MR phenomenon. Echo signals based on the MR phenomenon are acquired so as to obtain an image of MR data. The controller alternately and repetitively executes a first operation for applying the read gradient field while repetitively inverting it so as to produce the echo signal, and a second operation for applying, as the radio-frequency magnetic field, a 180.degree. pulse which can compensate for an echo signal phase error due to a nonuniformity and offset of the static magnetic field so as to generate the echo signal. The controller also inverts the phase encoding gradient field each time the 180.degree. pulse is applied.

摘要翻译： 在本发明的MRI系统中，根据控制器的预定顺序将脉冲RF场和脉冲切片相位编码和读取梯度场应用于放置在均匀静磁场中的被检体， 从而导致MR现象。 获取基于MR现象的回波信号，以获得MR数据的图像。 控制器交替重复地执行用于施加读取的梯度场的第一操作，同时重复地反转它以产生回波信号，以及第二操作，作为射频磁场施加可以补偿的180度脉冲 由于静态磁场的不均匀性和偏移引起的回波信号相位误差，以产生回波信号。 每当施加180°脉冲时，控制器也会反相相位编码梯度场。

公开(公告)号：US5043665A

公开(公告)日：1991-08-27

申请号：US442626

申请日：1989-11-29

申请人： Shigehide Kuhara ,  Kozo Satoh

发明人： Shigehide Kuhara ,  Kozo Satoh

IPC分类号： G01R33/44 ,  A61B5/055 ,  G01R33/48 ,  G01R33/561

CPC分类号： G01R33/561

摘要： A magnetic resonance imaging system collects all the data required for image reconstruction of a predetermined portion of an object under examination by one excitation process in accordance with a pulse sequence in which, after excitation of spins within the predetermined portion by a radio frequency magnetic field and a gradient magnetic field, a predetermined readout gradient magnetic field is applied switched positive and negative at high speed to produce multiechoes on both sides of a spin echo center and a predetermined phase encoding gradient magnetic field is applied whose amount and sequence in encode steps are controlled so that multiecho data or its complex conjugate data may scan substantially the half of a Fourier data plane. By taking the complex conjugate of the magnetic resonance data collected in that way and then two-dimensional Fourier transforming the magnetic resonance data and the complex conjugate data, a magnetic resonance image of the predetermined portion of the object is obtained.

公开(公告)号：US4920314A

公开(公告)日：1990-04-24

申请号：US164496

申请日：1988-03-04

申请人： Kozo Satoh

发明人： Kozo Satoh

IPC分类号： A61B5/055 ,  A61B10/00 ,  G01R33/48 ,  G01R33/54 ,  G01R33/563

CPC分类号： G01R33/482 ,  G01R33/563

摘要： A magnetic resonance system is arranged to invert the polarity of a slicing gradient magnetic field pulse each time the selective excitation is repeated, and additively combine two types of imaging data corresponding to the opposite polarities of the slicing gradient field pulse to form a magnetic resonance image.

摘要翻译： 磁共振系统被布置成每次重复选择性激励时反转切片梯度磁场脉冲的极性，并且加法地组合对应于切片梯度场脉冲的相反极性的两种类型的成像数据以形成磁共振图像 。

公开(公告)号：US5063348A

公开(公告)日：1991-11-05

申请号：US484048

申请日：1990-02-23

申请人： Shigehide Kuhara ,  Kozo Satoh

发明人： Shigehide Kuhara ,  Kozo Satoh

IPC分类号： G01R33/36 ,  G01R33/56 ,  G01R33/561 ,  G01R33/565

CPC分类号： G01R33/5615 ,  G01R33/3607 ,  G01R33/56 ,  G01R33/56545 ,  G01R33/5616 ,  G01R33/56554

摘要： In an MRI system, an RF field and slicing, phase encoding, and read-out gradient fields are applied to an object to be examined which is placed in a homogeneous static field in a predetermined sequence. An MR signal from a region of interest in the object is received through a probe, and is detected by a detection circuit using a predetermined reference wave. A detection output from the synchronous detection circuit is sampled to acquire MR signal data and to obtain diagnostic data. The system includes a reference wave control section for shifting the frequency and phase of the reference wave, by predetermined amounts, from the frequency and phase of an MR signal when the phase encoding and read-out gradient fields are zero. The reference wave control section changes a frequency shift value of the reference wave to positive and negative phases in synchronism with switching of the gradient fields, and changes a phase shift value of the reference wave stepwise.

公开(公告)号：US4999581A

公开(公告)日：1991-03-12

申请号：US362443

申请日：1989-05-30

申请人： Kozo Satoh

发明人： Kozo Satoh

IPC分类号： A61B10/00 ,  A61B5/055 ,  G01R33/32 ,  G01R33/36 ,  G01R33/44 ,  G01R33/48

CPC分类号： G01R33/3621

摘要： A magnetic resonance imaging system includes magnetic resonance signal detecting means (1, 2, 3, 4, 7, 8, 10) for detecting a magnetic resonance signal from an object to be examined, receiving means (9) for phase-sensitive detecting and amplifying the magnetic resonance signal, data acquiring means (11) for sampling and digitizing the magnetic resonance signal obtained by the receiving unit (9), and image reconstructing means (12) for performing image reconstruction on the basis of the magnetic resonance signal and the sampling data obtained by the data acquiring means (11). The magnetic resonance imaging system includes a reference signal phase correcting circuit (26) for correcting a phase of a phase-sensitive detecting reference signal, a base line correcting circuit (27) for correcting a base line of the magnetic resonance signal detected by the magnetic resonance signal detecting means (1, 2, 3, 4, 7, 8, 10), and a sampling point correcting circuit (28) for correcting a sampling point of the magnetic resonance signal in the data acquiring means (11).

公开(公告)号：US4746860A

公开(公告)日：1988-05-24

申请号：US31132

申请日：1987-03-30

申请人： Kozo Satoh

发明人： Kozo Satoh

IPC分类号： A61B10/00 ,  A61B5/055 ,  G01R33/48 ,  G01R33/54 ,  G01R33/565 ,  G01R33/20

CPC分类号： G01R33/482 ,  G01R33/56509

摘要： In a magnetic resonance imaging system, a radio frequency field for exciting a magnetic resonance phenomenon, a first gradient field for determining a image slice, a second gradient field for phase-encoding, and a third gradient field for reading out an echo signal of the magnetic resonance, are applied to a subject in the static field. Thus, the echo signal is acquired, and image reconstruction data is obtained from the echo signal, whereby reconstructed image information is obtained. A correction data generating section uses the second gradient field as a gradient field for reading out the echo signal, and applies the first and second gradient fields, and the radio frequency field to the subject in the static field, in accordance with a predetermined sequence, without applying a gradient field for phase-encoding, and acquires the echo signal, so as to obtain correction data corresponding to the image reconstruction data along an encoding axis. A correcting section corrects the image reconstruction data, using the correction data.

摘要翻译： 在磁共振成像系统中，用于激发磁共振现象的射频场，用于确定图像切片的第一梯度场，用于相位编码的第二梯度场，以及用于读出第二梯度场的回波信号 磁共振，被施加到静态场所的受试者。 因此，获取回波信号，并且从回波信号获得图像重建数据，由此获得重建的图像信息。 校正数据生成部使用第二梯度场作为读出回波信号的梯度场，并且根据预定的顺序将静态场中的第一和第二梯度场以及射频场施加到被摄体， 而不施加用于相位编码的梯度场，并且获取回波信号，以便获得与编码轴对应的图像重建数据的校正数据。 校正部使用校正数据校正图像重建数据。

公开(公告)号：US5055789A

公开(公告)日：1991-10-08

申请号：US480767

申请日：1990-02-16

申请人： Masafumi Kondo ,  Kozo Satoh

发明人： Masafumi Kondo ,  Kozo Satoh

IPC分类号： A61B5/055 ,  G01R33/48 ,  G01R33/561

CPC分类号： G01R33/56554

摘要： An MRI system applies a phase encoding gradient field, a read-out gradient field, and an RF field to an object which is placed in a homogeneous static field in accordance with a predetermined pulse sequence so as to excite MR at a specific slice plane of the object, thereby detecting an MR signal from the object and visualizing the slice plane. The system includes a data acquiring section for acquiring all the data required for image reconstruction of the slice portion excited by the RF field within a time in which magnetization in the slice plane is relaxed, by switching the read-out gradient field to positive and negative polarities, an image reconstructing section for obtaining positive and negative time phase images which are respectively based on data acquired when the read gradient field is at positive time phases and data acquired when the read gradient field is at negative time phases by performing image reconstruction based on the respective data, a correcting section for correcting an image degradation factor for each time phase images, and an image synthesizing section for obtaining an MR image of the slice portion by synthesizing both time phase images corrected by the correcting section.

公开(公告)号：US4549137A

公开(公告)日：1985-10-22

申请号：US506290

申请日：1983-06-21

申请人： Hirokazu Suzuki ,  Kozo Satoh

发明人： Hirokazu Suzuki ,  Kozo Satoh

IPC分类号： A61B10/00 ,  A61B5/055 ,  G01R33/48 ,  G01R33/483 ,  G01R33/54 ,  G01N24/08

CPC分类号： G01R33/482 ,  G01R33/4838

摘要： Nuclear magnetic resonance diagnostic apparatus including means for applying a gradient magnetic field to form an equivalent plane in the magnetic field corresponding to the slice in the predetermined region to be measured for the acquisition of projection data, means for selectively saturating magnetization vectors in the entire region other than the region corresponding to the slice by applying radio frequency signal composed of continuous waves the frequency of which is successively varied in the range of the resonance frequency of the specified atomic nuclei and means for obtaining the projection data in the predetermined directions in the slice by measuring the resonance signals obtained by applying the 90.degree. pulses of resonance frequency of the specified atomic nuclei to the region to be measured while the saturation state of magnetization vectors is maintained.

摘要翻译： 核磁共振诊断装置包括用于施加梯度磁场以在对应于要测量的预定区域中的切片的磁场中形成等效平面以获取投影数据的装置，用于选择性地饱和整个区域中的磁化矢量的装置 通过施加由连续波构成的射频信号，其频率在特定原子核的共振频率的范围内依次变化的连续波的区域以及在切片中的预定方向获得投影数据的单元 通过测量在维持磁化矢量的饱和状态的同时，将指定的原子核的共振频率的90°脉冲施加到待测量的区域而获得的共振信号。