公开(公告)号：US20180081013A1

公开(公告)日：2018-03-22

申请号：US15558263

申请日：2015-04-07

Applicant: Hitachi, Ltd.

Inventor： Yo TANIGUCHI ,  Hiroyuki TAKEUCHI ,  Toru SHIRAI ,  Suguru YOKOSAWA ,  Shinji KUROKAWA ,  Hisaaki OCHI

IPC: G01R33/385

CPC classification number: G01R33/3854 ,  A61B5/055 ,  G01R33/482

Abstract: In an MRI apparatus, an imaging that produces almost no sound is implemented without extending an imaging time, not only for three-dimensional imaging, but also for two-dimensional imaging. A gradient pulse in a pulse sequence provided in the MRI apparatus is adjusted by using a basic waveform having a distribution of frequencies where strength dwindles substantially as the frequency increases from zero, and the waveform is convex upward or downward varying smoothly. An application time and strength are adjusted so that almost no sound is produced. Any imaging executable by a conventional pulse sequence can be implemented without producing almost any sound, using the conventional pulse sequence with little change.

公开(公告)号：US20170209067A1

公开(公告)日：2017-07-27

申请号：US15107540

申请日：2015-08-06

Applicant: HITACHI, LTD.

Inventor： Yo TANIGUCHI ,  Suguru YOKOSAWA ,  Hisaaki OCHI ,  Toru SHIRAI ,  Shinji KUROKAWA

IPC: A61B5/055

CPC classification number: A61B5/055 ,  G01R33/246 ,  G01R33/4835 ,  G01R33/50 ,  G01R33/5602 ,  G01R33/5608 ,  G01R33/5616

Abstract: A technology of improving image quality of a calculation image or parameter estimation accuracy even in a case where a method of simultaneously generating calculation images of a plurality of parameters is used is provided. Thus, by utilization of a reconstructed image in an optimal resolution of each parameter to be estimated, a value of the parameter is estimated and a calculation image that is a distribution of the value of the parameter is acquired. A reconstructed image in an optimal resolution is acquired by adjustment of a resolution of a reconstructed image acquired in an optimal resolution of an estimation parameter with the highest optimal resolution among parameters to be estimated in scanning. Alternatively, in scanning, only a reconstructed image used for calculation of a predetermined parameter to be estimated is acquired in an optimal resolution of the parameter to be estimated.

公开(公告)号：US20200278411A1

公开(公告)日：2020-09-03

申请号：US16756177

申请日：2018-08-24

Applicant: HITACHI, LTD.

Inventor： Suguru YOKOSAWA ,  Yo TANIGUCHI ,  Tomoki AMEMIYA ,  Toru SHIRAI ,  Hisaaki OCHI

IPC: G01R33/561 ,  G01R33/50 ,  G01R33/56 ,  A61B5/055

Abstract: An MRI device for executing an imaging operation at least three times or more with a different combination of at least a repetition time and a flip angle in the same imaging sequence, includes: a receiving unit which receives information specifying an imaging target and a constraint condition relating to an imaging time or quantitative value accuracy; and a scan parameter set generation unit which calculates at least three or more scan parameter sets having a different combination of at least the repetition time and the flip angle on the basis of the constraint condition. The MRI device uses three or more scan parameter sets generated by the optimal scan parameter set generation unit and calculates quantitative values (T1, T2, and the like) of the imaging target from a plurality of images obtained by the imaging operation.

公开(公告)号：US20180338701A1

公开(公告)日：2018-11-29

申请号：US15911289

申请日：2018-03-05

Applicant: Hitachi, Ltd.

Inventor： Tomoki AMEMIYA ,  Suguru YOKOSAWA ,  Yo TANIGUCHI ,  Hisaaki OCHI ,  Yoshihisa SOTOME

IPC: A61B5/055 ,  G01R33/561 ,  G01R33/563

Abstract: A system is disclosed to simultaneously acquire a magnetic resonance angiography (MRA) image and a plurality of images in which the structure of a tissue other than a blood vessel can be ascertained without performing imaging for the MRA image, and to shorten a time of MR examination. Two or more kinds of physical property dependent images obtained from a nuclear magnetic resonance signal measured in accordance with a predetermined pulse sequence under a plurality of imaging conditions are combined using a predetermined combination function. At this time, a plurality of division regions are set in the physical property dependent image, and the combination parameter satisfying a condition that a difference between a pixel value of the specific tissue and a pixel value of a tissue other than the specific tissue increases is determined at each of the division regions in the actually measured two or more kinds of physical property dependent images, using standard data of the two or more kinds of physical property dependent images, and the combination parameter is used to combine the two or more kinds of images.

公开(公告)号：US20160025824A1

公开(公告)日：2016-01-28

申请号：US14760846

申请日：2013-12-04

Applicant: HITACHI, LTD. ,  HITACHI MEDICAL CORPORATION

Inventor： Yo TANIGUCHI ,  Masahiro TAKIZAWA ,  Takeshi YATSUO ,  Atsushi KURATANI

IPC: G01R33/385 ,  G01R33/565 ,  G01R33/58

CPC classification number: G01R33/3852 ,  G01R33/546 ,  G01R33/56572 ,  G01R33/58

Abstract: A magnetic resonance imaging device produces a magnetic field gradient with parallel driving of positive-side subcoils and negative-side subcoils with different power sources in the magnetic field gradient direction, to detect a misalignment in drive timing of the positive side and the negative side. Pulse sequences for timing misalignment detection having a slice magnetic field gradient pulse and a read-out magnetic field gradient pulse in the same direction as a magnetic field gradient of interest are executed. A positive-side slice echo and a negative-side slice echo of the magnetic field gradient are acquired. A phase difference between a positive-side projection image and a negative-side projection image is derived by computation with phase error from other factors being removed. From the slope of the phase difference with respect to a location, the drive timing misalignment between the positive-side subcoil and the negative-side subcoil of the magnetic field gradient production is detected.

Abstract translation: 磁共振成像装置在磁场梯度方向上产生具有不同电源的正侧子线圈和负侧子线圈的平行驱动的磁场梯度，以检测正侧和负侧的驱动定时中的未对准。 执行具有与感兴趣的磁场梯度相同方向的切片磁场梯度脉冲和读出磁场梯度脉冲的定时未对准检测的脉冲序列。 获取磁场梯度的正侧切片回波和负侧切片回波。 正面投影图像和负侧投影图像之间的相位差通过计算得出，相位误差从其他因素被去除。 从相位差相对于位置的斜率检测出磁场梯度产生的正侧次线圈与负侧次线圈之间的驱动定时偏移。

公开(公告)号：US20190261906A1

公开(公告)日：2019-08-29

申请号：US16342612

申请日：2017-10-11

Applicant: Hitachi, Ltd.

Inventor： Toru SHIRAI ,  Ryota SATOH ,  Yo TANIGUCHI ,  Hisaaki OCHI ,  Yoshihisa SOTOME ,  Yoshitaka BITO ,  Takenori MURASE

IPC: A61B5/145 ,  G01R33/56 ,  G01R33/54 ,  G01R33/44 ,  A61B5/055 ,  A61B5/00

Abstract: Provided is a technique for calculating an oxygen extraction fraction by using MRI where the oxygen extraction fraction in a brain including brain parenchyma is calculated via a simple processing without an impact on an examinee, such as administration of caffeine. For this purpose, an MRI apparatus of the present invention measures a complex image of nuclear magnetic resonance signals, and calculates from thus measured complex image, a physical property distribution for obtaining a physical property image reflecting the oxygen extraction fraction. Then, thus calculated physical property distribution is separated into tissue-specific physical property distributions for at least two tissues (separated tissue images). After converting any of the separated tissue images into the oxygen extraction fraction, a distribution of the oxygen extraction fraction is estimated based on the condition that a value of any selected pixel is substantially equal to a mean value of pixels surrounding the selected pixel.

公开(公告)号：US20180284208A1

公开(公告)日：2018-10-04

申请号：US15759112

申请日：2016-02-05

Applicant: HITACHI, LTD.

Inventor： Tomoki AMEMIYA ,  Suguru YOKOSAWA ,  Yo TANIGUCHI ,  Hisaaki OCHI

IPC: G01R33/56 ,  A61B5/026 ,  G06T3/40 ,  G06T5/40 ,  G01R33/563

Abstract: A medical image diagnosis supporting apparatus includes a quantitative value reception unit that receives data of kinds of quantitative values obtained in advance at points in a region of a subject; a variable conversion unit that calculates kinds of intermediate information values dependent on the kinds of quantitative values at each of the points using the kinds of quantitative values at each of the points and kinds of variable conversion functions; and a diagnosis image calculation unit that calculates a diagnosis image for the region. The diagnosis image calculation unit sets a pixel value at each of the points in accordance with a combination of kinds of intermediate information values obtained at each of the points by the variable conversion unit or a combination of intermediate information values and kinds of quantitative values at the point and generates the diagnosis image.

公开(公告)号：US20180028273A1

公开(公告)日：2018-02-01

申请号：US15614782

申请日：2017-06-06

Applicant: Hitachi, Ltd.

Inventor： Suguru YOKOSAWA ,  Yo TANIGUCHI ,  Hisaaki OCHI ,  Tomoki AMEMIYA ,  Yoshihisa SOUTOME

IPC: A61B90/00 ,  H04N19/105

CPC classification number: A61B90/37 ,  A61B5/055 ,  A61B2090/374 ,  G01R33/00 ,  G01R33/50 ,  G01R33/5608 ,  G01R33/561 ,  H04N19/105

Abstract: There is provided an MRI apparatus in which, when a quantitative value, which does not depend on imaging parameter values, is computed from a plurality of image data having different pixel values that are acquired by performing imaging the plurality of times with different imaging parameter values in the same pulse sequence, pixel values which are acquired from the imaging parameter values are predicted for each of a plurality of predetermined quantitative-value candidate group, and an initial value of the quantitative value is selected from the quantitative-value candidate groups with reference to the predicted pixel values. The optimal quantitative value is computed through a localized optimization technique using the selected initial value.

公开(公告)号：US20170192068A1

公开(公告)日：2017-07-06

申请号：US15313983

申请日：2015-05-19

Applicant: Hitachi, Ltd.

Inventor： Yo TANIGUCHI ,  Toru SHIRAI ,  Hisaaki OCHI

IPC: G01R33/385 ,  G01R33/561 ,  A61B5/055

CPC classification number: G01R33/3854 ,  A61B5/055 ,  G01R33/288 ,  G01R33/561

Abstract: Acoustic noise reduction is achieved in a high-speed imaging method such as a phase-compensation type GE sequence, which is not provided with sufficiently long intervals for applying the gradient magnetic field pulses. A band-stop filter is used to reduce components of a frequency band in the gradient magnetic field waveform, having a high sound pressure level being a source of sound, thereby performing the noise reduction. In general, when a band of the gradient magnetic field is reduced, the waveform is likely to be considerably distorted, failing to satisfy imaging conditions. Therefore, the distorted waveform is shaped so that the imaging conditions are satisfied. The sound pressure level of the gradient magnetic field waveform is calculated by using a response function inherent to the device.

公开(公告)号：US20160161580A1

公开(公告)日：2016-06-09

申请号：US14904202

申请日：2013-08-07

Applicant: HITACHI, LTD.

Inventor： Toru SHIRAI ,  Yo TANIGUCHI ,  Hisaaki OCHI

IPC: G01R33/48 ,  G01R33/34 ,  G01R33/56 ,  G01R33/38 ,  A61B5/055 ,  G01R33/54

CPC classification number: G01R33/4828 ,  A61B5/00 ,  A61B5/055 ,  G01R33/34053 ,  G01R33/3806 ,  G01R33/485 ,  G01R33/543 ,  G01R33/5607 ,  G01R33/5608

Abstract: Restriction on echo intervals is to be reduced in the Dixon's method without sacrificing separation performance and image quality. An image is reconstructed from echo signals measured at three or more different echo times. First and second peak frequency distributions in which aliasing (folding) due to echo time intervals is removed are calculated from the obtained images, and the first and second peak frequency distributions are used to obtain an offset frequency distribution. Note that these first peak frequency distribution and second peak frequency distribution are a distribution of peak frequencies obtained on the assumption that all of the pixels are the first substance and a distribution of peak frequencies obtained on the assumption that all of the pixels are the second substance, respectively. The offset frequency distribution and the obtained images are used to separate an image of the first substance from an image of the second substance.

Abstract translation: 在Dixon的方法中减少对回波间隔的限制，而不会牺牲分离性能和图像质量。 从在三个或更多个不同回波时间测量的回波信号重建图像。 从所获得的图像中计算由于回波时间间隔而导致的混叠（折叠）的第一和第二峰值频率分布，并且使用第一和第二峰值频率分布来获得偏移频率分布。 注意，这些第一峰值频率分布和第二峰值频率分布是假定所有像素都是第一物质而获得的峰值频率的分布，并且假定所有像素都是第二物质而获得的峰值频率分布 ， 分别。 偏移频率分布和所获得的图像用于将第一物质的图像与第二物质的图像分离。