Toshiba Medical Systems Corporation

Kabushiki Kaisha Toshiba

Canon Medical Systems Corporation

Kyoto University

Hiroshi Kusahara

Yutaka Machii

Yoshimori Kassai

Yuki Takai

Satoshi Sugiura

Masao Yui

Masashi Hori

Masaaki Umeda

Yoshitomo Sakakura

Koji Fujimoto

Naoyuki Furudate

Motohiro Miura

Masaaki Nagashima

Takashi Shigeta

Hiroyoshi Isoda

According to one embodiment, a magnetic resonance imaging apparatus includes processing circuitry. The processing circuitry sets imaging parameters for each scan. The processing circuitry specifies the size of the object region in the phase encode direction from a first image. The first image acquired by using a pulse sequence different from EPI. The processing circuitry sets parameters in a field of view in the phase encode direction in a phase correction scan based on the specified size and the size of the field of view in the phase encode direction in a second scan. The phase correction scan is executed for acquiring phase correction information for the first image. The second scan is executed for acquiring a second image by using EPI.

Magnetic resonance imaging apparatus

A magnetic-resonance imaging apparatus of an embodiment includes a gradient coil, a transmitter coil, and a processing circuitry. The gradient coil applies a gradient magnetic field to an imaging space in which a subject is placed. The transmitter coil applies a RF (radio frequency) pulse to the imaging space. The processing circuitry calculates a target temperature of the gradient coil throughout multiple protocols to be executed in an examination of the subject, and controls a temperature of the gradient coil to approach the target temperature when a data used to set a center frequency of the RF pulse is measured.

Magnetic-resonance imaging apparatus

A magnetic resonance imaging apparatus according to one embodiment includes a sequence controller, a correction map generator, an image generator, and a corrector. The sequence controller executes first data acquisition to acquire data for a phase correction map, and second data acquisition to acquire data of a cluster of images corresponding to a plurality of time phases. The correction map generator generates the phase correction map by using echo signals acquired through the first data acquisition. The image generator generates the cluster of images corresponding to the time phases by using echo signals acquired through the second data acquisition. The corrector corrects a phase of each image included in the cluster of images, based on the phase correction map and changes in phase of echo signals that occur between time phases.

Magnetic resonance imaging apparatus and method correcting phases in images corresponding to a plurality of time phases

A magnetic resonance imaging apparatus according to an embodiment includes sequence controlling circuitry and image generating circuitry. The sequence controlling circuitry acquires magnetic resonance signals in an imaging region. The image generating circuitry generates an image. The sequence controlling circuitry sets timings of RF pulses such that a first time and a second time are different. Here, the first time is a time since an irradiation of a first RF pulse without selection of region until a start of acquisition. The second time is a time since an irradiation of a second RF pulse with selection of the labeling region until the start of acquisition. The second time is also a time for a liquid present in the labeling region to reach a desired position in the imaging region. The first time is also a time for longitudinal magnetization components of a background tissue to become substantially zero.

A control device of a magnetic resonance (MRI) imaging apparatus includes a condition setting unit and a judging unit. The condition setting unit sets an imaging sequence to be performed by the magnetic resonance imaging apparatus based on set conditions of the set imaging sequence. The judging unit then (a) calculates a value of electric current supplied to a gradient magnetic field coil of the MRI apparatus to perform that set imaging sequence based on the set conditions of the set imaging sequence, (b) calculates a value of voltage that would need to be applied to the gradient magnetic field coil based on a mutual inductance of the gradient magnetic field to cause electric current flowing to the gradient magnetic field coil to become equal to the value of the calculated electric current, and (c) judges whether the set imaging sequence is practicable or not based on the calculated value of voltage.

Magnetic resonance imaging apparatus and control device of a magnetic resonance imaging apparatus

According to one embodiment, an MRI apparatus includes a gradient coil, an RF coil, an RF receiver, and processing circuitry which controls these components to perform each pulse sequence. The processing circuitry sets a main-scan pulse sequence, a first pulse sequence which includes application of a gradient magnetic field in a readout direction, and a second pulse sequence which includes application of the gradient magnetic field in a readout direction, and whose acquisition region is shifted from the first pulse sequence. The processing circuitry reconstructs image data of the main scan, based on magnetic resonance signals acquired by the main-scan pulse sequence and phase difference data in the readout direction between first k-space data generated from the magnetic resonance signals acquired by the first pulse sequence and second k-space data generated from the magnetic resonance signals acquired by the second pulse sequence.

Magnetic resonance imaging apparatus and magnetic resonance imaging method

A magnetic resonance imaging apparatus according to an embodiment includes a controller and a generator. The controller divides a plurality of slice regions that are sequentially arranged into a first group including two non-sequential slice regions and a second group including a slice region positioned between the two non-sequential slice regions and acquires data from the slice regions for each of the groups. When acquiring data from at least one of the two non-sequential slice regions, the controller acquires the data after applying a pre-sat pulse to a position between the two non-sequential slice regions. When acquiring data from the slice region positioned between the two non-sequential slice regions, the controller acquires the data after applying a pre-sat pulse to a position of at least one of the two non-sequential slice regions.

According to one embodiment, a magnetic resonance imaging apparatus includes a data acquisition unit, an eddy magnetic field measuring unit and an imaging unit. The data acquisition unit is configured to acquire magnetic resonance signals at mutually different timings with applying a gradient magnetic field for generating an eddy magnetic field. The eddy magnetic field measuring unit is configured to acquire eddy magnetic field information including a time constant of the eddy magnetic field based on phase information of the magnetic resonance signals acquired at the timings. The imaging unit is configured to perform imaging under an imaging condition or a data processing condition according to the eddy magnetic field information.

An MRI apparatus produces a plurality of echo signals by performing an EPI echo signal acquisition sequence including gradient magnetic fields in a phase encoding direction, and acquires a plurality of echo signals as first and second template data, respectively. The second template data is acquired using a sequence in which start timing of a gradient magnetic field in a readout direction is shifted from the case where acquisition of the first template data is performed. The phase error included in the echo signals is corrected by using the first and second template data.

According to one embodiment, a magnetic resonance imaging apparatus includes an imaging unit and a strain correction unit. The imaging unit is configured to acquire frames of diffusion weighted image data corresponding to different b-values by diffusion weighted imaging with applying MPG pulses corresponding to the different b-values of which application axes are same. The strain correction unit is configured to calculate a strain correction coefficient for diffusion weighted image data to be a target of a strain correction based on diffusion weighted image data corresponding to a b-value different from a b-value corresponding to the diffusion weighted image data to be the target of the strain correction among the frames of the diffusion weighted image data to generate image data after the strain correction by the strain correction of the diffusion weighted image data to be the target of the strain correction using the calculated strain correction coefficient.

A magnetic resonance imaging apparatus has a storage unit and a processing unit. The storage unit stores correction data of a position coordinate, in which the position coordinate in the reconstruction FOV is caused to correspond to a position coordinate in a display FOV included in the reconstruction FOV based on an intensity of a gradient magnetic field. If both of a first position coordinate and a second position coordinate, which is further from the center of the reconstruction FOV, correspond to same position coordinate in the display FOV, the correction data is data for causing only the first position coordinate to correspond to the position coordinate in the display FOV. The processing unit corrects a reconstructed image based on the correction data and obtains an image of the display FOV.

Growing community of inventors

Utsunomiya, Japan

Hiroshi Kusahara