Patents by Inventor Shinji Kurokawa

Shinji Kurokawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20220128639
    Abstract: A problem of time elongation in image reconstruction due to necessity of many iterations is solved, when an image is reconstructed by performing iterative approximation on measurement data acquired by an MRI apparatus without full-sampling. Density is estimated in the course of the iteration, and density is corrected using thus estimated density. Density estimation is performed not only on initial values but also on every iteration process, thereby enabling convergence with a smaller number of iterations.
    Type: Application
    Filed: October 14, 2021
    Publication date: April 28, 2022
    Inventor: Shinji Kurokawa
  • Publication number: 20210333347
    Abstract: Provided is a magnetic resonance imaging apparatus with no occurrence of artifacts, even after noise removal by applying Wavelet transform to a zero-fill reconstructed image. Nuclear magnetic resonance signals acquired by the magnetic resonance imaging apparatus are processed to perform reconstruction with a reconstruction matrix extended by zero-filling an acquisition matrix, and then a zero-fill reconstructed image is produced. This reconstructed image is subjected to an iterative operation combining the Wavelet transform and L1 norm minimization to remove noise. Before the noise removal, a pre-processing is performed to change the reconstruction matrix size so that an artifact does not occur in the image after noise removal, an artifact portion appears outside the reconstruction matrix after the noise removal, or cutting out is performed so that no artifact appears after the noise removal. The matrix size is restored to its original size in the post-processing after the noise removal.
    Type: Application
    Filed: March 18, 2021
    Publication date: October 28, 2021
    Inventors: Hiroki SHOJI, Toru SHIRAI, Shinji KUROKAWA
  • Patent number: 11122988
    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.
    Type: Grant
    Filed: August 6, 2015
    Date of Patent: September 21, 2021
    Assignee: HITACHI, LTD.
    Inventors: Yo Taniguchi, Suguru Yokosawa, Hisaaki Ochi, Toru Shirai, Shinji Kurokawa
  • Patent number: 11080825
    Abstract: Provided is a novel aliasing elimination technique capable of suppressing noise amplification in an aliasing elimination calculation in parallel imaging and the like. The technique utilizes the fact that a phase of an image (a true image that is one of a plurality of images) to be separated from a main captured image obtained with the plurality of images superimposed is basically the same as a phase of an image obtained at a low resolution, to obtain a phase difference between a phase of a low-resolution image and a phase of the main captured image, and separates the true image by calculation using the phase difference and a pixel value of the main captured image. At this time, the low-resolution image is obtained by each of a plurality of receiving coils, and the true image is calculated after multiplying a plurality of low-resolution images by a complex number that minimizes the noise amplification.
    Type: Grant
    Filed: July 5, 2018
    Date of Patent: August 3, 2021
    Assignee: HITACHI, LTD.
    Inventors: Kousuke Itou, Shinji Kurokawa, Masahiro Takizawa
  • Publication number: 20200126188
    Abstract: Provided is a novel aliasing elimination technique capable of suppressing noise amplification in an aliasing elimination calculation in parallel imaging and the like. The technique utilizes the fact that a phase of an image (a true image that is one of a plurality of images) to be separated from a main captured image obtained with the plurality of images superimposed is basically the same as a phase of an image obtained at a low resolution, to obtain a phase difference between a phase of a low-resolution image and a phase of the main captured image, and separates the true image by calculation using the phase difference and a pixel value of the main captured image. At this time, the low-resolution image is obtained by each of a plurality of receiving coils, and the true image is calculated after multiplying a plurality of low-resolution images by a complex number that minimizes the noise amplification.
    Type: Application
    Filed: July 5, 2018
    Publication date: April 23, 2020
    Applicant: Hitachi, Ltd.
    Inventors: Kousuke ITOU, Shinji KUROKAWA, Masahiro TAKIZAWA
  • Patent number: 10436862
    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.
    Type: Grant
    Filed: April 7, 2015
    Date of Patent: October 8, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Yo Taniguchi, Hiroyuki Takeuchi, Toru Shirai, Suguru Yokosawa, Shinji Kurokawa, Hisaaki Ochi
  • Patent number: 10416266
    Abstract: In multi-echo imaging, in imaging in which pulses other than a 180° pulse are included in refocus RF pulses, a high-quality image in which the intended contrast is emphasized is obtained by reducing unnecessary contrast. Therefore, imaging parameters are adjusted so as to reduce the unnecessary contrast. The adjustment is performed so that, for echo signals from tissues having the same relaxation time to cause intended contrast among echo signals from a plurality of tissues having different relaxation times, the difference between the signal strengths of echo signals to determine the contrast, such as echo signals at the k-space center, is reduced. Imaging parameters to be adjusted include a repetition time, the FA of a DE pulse, the FA of a saturation pulse, the application timing of the saturation pulse, the application strength of a gradient magnetic field in a recovery period, application timing, and the like.
    Type: Grant
    Filed: February 13, 2014
    Date of Patent: September 17, 2019
    Assignee: HITACHI, LTD.
    Inventor: Shinji Kurokawa
  • Patent number: 10401444
    Abstract: A quantitative image (resonance frequency map) of a resonance frequency difference is obtained using a high-speed phase compensated pulse sequence of a gradient echo (GE) system. A signal function of the pulse sequence used when obtaining the resonance frequency map is generated by a numerical simulation. The high-speed phase compensated pulse sequence uses a BASG sequence, for example.
    Type: Grant
    Filed: January 30, 2015
    Date of Patent: September 3, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Yo Taniguchi, Toru Shirai, Suguru Yokosawa, Shinji Kurokawa, Hisaaki Ochi
  • Patent number: 10219762
    Abstract: An X-ray CT device which improves resolution in a peripheral region distant from a rotation center. According to an FFS method of moving an X-ray focal point, a gap width of projection positions on an X-ray detector of a first X-ray trajectory from the X-ray focal point of a first view and a second X-ray trajectory from the X-ray focal point of a second view is obtained. A position of the X-ray focal point of the first and second views is set so that a gap width 15 of the projection positions on the X-ray detector of the first X-ray trajectory and the second X-ray trajectory which pass through a point within a predetermined first region close to the X-ray focal point from the rotation center is closer to (N?½) times (N=any one of 1, 2, 3, . . . ) of a width of a channel of the X-ray detector.
    Type: Grant
    Filed: June 22, 2015
    Date of Patent: March 5, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Shinji Kurokawa, Yushi Tsubota
  • Patent number: 10169866
    Abstract: To provide a technique for supporting diagnosis by reducing a user's time and effort in quantitative diagnosis using a quantitative value acquired by a medical image acquisition apparatus. A user is allowed in advance to select only desired diagnostic information from vast amounts of diagnostic information such as images and numerical values. Only the selected diagnostic information is presented to the user in a user-friendly mode. The diagnostic information is calculated by using a physical property value necessary for the calculation of the diagnostic information in question and calculation information such as arithmetic functions and variables, the physical property value and calculation information being stored in advance.
    Type: Grant
    Filed: April 22, 2014
    Date of Patent: January 1, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Suguru Yokosawa, Yo Taniguchi, Hisaaki Ochi, Toru Shirai, Shinji Kurokawa
  • Patent number: 10073159
    Abstract: In order to maximize the SNR of an image in consideration of signal correction in a multi-echo sequence, flip angles of a plurality of refocus high frequency magnetic field pulses are determined in a multi-echo imaging sequence. Using an index that reflects the SNR of an image after signal correction of a plurality of acquired echo signals, a flip angle at which the SNR of the image becomes a maximum is determined by repeatedly calculating the index by changing information specifying the flip angle of each refocus RF pulse according to an optimization method set in advance.
    Type: Grant
    Filed: May 23, 2012
    Date of Patent: September 11, 2018
    Assignee: HITACHI, LTD.
    Inventor: Shinji Kurokawa
  • Patent number: 10048341
    Abstract: When imaging is performed by executing a pulse sequence on an MRI apparatus, silencing is realized with securing sufficient application amount of crusher without extending the application time thereof. In the pulse sequence carried by the MRI apparatus, at least one gradient magnetic field pulse included in the pulse sequence has a waveform synthesized from two or more base waves shifting along the time axis direction (synthesized waveform), and the base waves have a smoothly changing waveform convex upward. The pulse of the synthesized waveform is generated from one or more trapezoidal or triangular base pulses by a waveform conversion part of a computer of the MRI apparatus or an external computer.
    Type: Grant
    Filed: February 6, 2015
    Date of Patent: August 14, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yo Taniguchi, Toru Shirai, Suguru Yokosawa, Hisaaki Ochi, Shinji Kurokawa, Hiroyuki Takeuchi
  • Patent number: 10022099
    Abstract: A change of X-ray radiation quality due to a material existing between an X-ray source and a detection element is estimated and corrected. Accordingly, deterioration of material discrimination ability in a dual energy imaging method can be prevented. An X-ray imaging apparatus is provided with an inherent filtration calculator configured to use measured data obtained by imaging air at two or more types of different tube voltages to calculate a deviation from a reference radiation quality, as a transmission length (inherent filtration) of a predetermined reference material. A reference-material transmission-length conversion is applied to the measured data according to the dual energy imaging method, thereby calculating the reference material transmission length (inherent filtration). When a subject is imaged, the dual energy imaging is performed by adding the inherent filtration calculated as to each detection element, and this produces an image with the change of radiation quality having been corrected.
    Type: Grant
    Filed: October 22, 2014
    Date of Patent: July 17, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yushi Tsubota, Fumito Watanabe, Yasutaka Konno, Shinichi Kojima, Keisuke Yamakawa, Shinji Kurokawa
  • Patent number: 9977137
    Abstract: Provided is a technique in an X-ray imaging apparatus for implementing data interpolation approximating an ideal point response trajectory interpolation, along with reducing calculation load. A method is provided to perform interpolation at high speed, in a direction along the point response trajectory. Sinograms are interpolated in advance from measured data, as to representative angles (e.g., 0°, ±30°, ±60°, and 90°) only. When a pixel targeted for back projection is determined at the time of reconstruction, a slope of the point response trajectory is determined as to each view. According to the slope of the trajectory, each representative sinogram is added with weight, whereby interpolation data in association with any angle can be obtained.
    Type: Grant
    Filed: July 23, 2015
    Date of Patent: May 22, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yushi Tsubota, Shinji Kurokawa, Keisuke Yamakawa, Yasutaka Konno, Shinichi Kojima, Fumito Watanabe
  • Publication number: 20180081013
    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.
    Type: Application
    Filed: April 7, 2015
    Publication date: March 22, 2018
    Inventors: Yo TANIGUCHI, Hiroyuki TAKEUCHI, Toru SHIRAI, Suguru YOKOSAWA, Shinji KUROKAWA, Hisaaki OCHI
  • Patent number: 9906524
    Abstract: Realized is a low-cost provision system capable of providing a provision item or a provision system that requires a smaller number of operation steps to be made by a user. A server includes a first receiving unit receiving transaction information transmitted by a communication terminal requesting a provision device having a provision item stored thereon to make a transaction of the provision item, a second receiving unit receiving a communication result including authentication information input to the communication terminal before the communication, the communication result being generated by a communication between the provision device and the communication terminal, and a transmission unit transmitting an instruction to execute the transaction to the provision device based on the transaction information or the communication result.
    Type: Grant
    Filed: August 30, 2016
    Date of Patent: February 27, 2018
    Assignee: THE BANK OF TOKYO-MITSUBISHI UFJ, LTD.
    Inventors: Makoto Shibata, Shinji Kurokawa, Yuji Kitada, Atsuo Ikeya, Takeshi Iketani
  • Publication number: 20170209067
    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.
    Type: Application
    Filed: August 6, 2015
    Publication date: July 27, 2017
    Inventors: Yo TANIGUCHI, Suguru YOKOSAWA, Hisaaki OCHI, Toru SHIRAI, Shinji KUROKAWA
  • Publication number: 20170202527
    Abstract: An X-ray CT device which improves resolution in a peripheral region distant from a rotation center. According to an FFS method of moving an X-ray focal point, a gap width of projection positions on an X-ray detector of a first X-ray trajectory from the X-ray focal point of a first view and a second X-ray trajectory from the X-ray focal point of a second view is obtained. A position of the X-ray focal point of the first and second views is set so that a gap width 15 of the projection positions on the X-ray detector of the first X-ray trajectory and the second X-ray trajectory which pass through a point within a predetermined first region close to the X-ray focal point from the rotation center is closer to (N?½) times (N=any one of 1, 2, 3, . . . ) of a width of a channel of the X-ray detector.
    Type: Application
    Filed: June 22, 2015
    Publication date: July 20, 2017
    Inventors: Shinji KUROKAWA, Yushi TSUBOTA
  • Publication number: 20170176609
    Abstract: Provided is a technique in an X-ray imaging apparatus for implementing data interpolation approximating an ideal point response trajectory interpolation, along with reducing calculation load. A method is provided to perform interpolation at high speed, in a direction along the point response trajectory. Sinograms are interpolated in advance from measured data, as to representative angles (e.g., 0°, ±30°, ±60°, and 90°) only. When a pixel targeted for back projection is determined at the time of reconstruction, a slope of the point response trajectory is determined as to each view. According to the slope of the trajectory, each representative sinogram is added with weight, whereby interpolation data in association with any angle can be obtained.
    Type: Application
    Filed: July 23, 2015
    Publication date: June 22, 2017
    Inventors: Yushi TSUBOTA, Shinji KUROKAWA, Keisuke YAMAKAWA, Yasutaka KONNO, Shinichi KOJIMA, Fumito WATANABE
  • Patent number: 9594133
    Abstract: In multi-echo multi-contrast imaging, the image quality is improved by suppressing an increase in imaging time. In order to do so, the arrangement order of echo signals that form an echo train and k space filled with each echo signal are determined such that the continuity of the echo arrangement is maintained while sharing an echo signal between contrasts in multi-echo multi-contrast imaging. Echo trains that perform echo sharing are arranged in non-oscillatory centric view ordering (NOCO). In addition, the starting point of echo sharing of one echo train is connected to the same position of another echo train. When some discontinuous regions are present, the discontinuous regions may be corrected using continuous data of regions symmetrical thereto on the k space.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: March 14, 2017
    Assignee: HITACHI, LTD.
    Inventors: Shinji Kurokawa, Norihiko Ozawa, Takayuki Abe