Abstract: According to one embodiment, a magnetic resonance imaging apparatus includes processing circuitry. The processing circuitry is configured to calculate an allowable amount of heat input to a superconducting magnet, the allowable amount being allocated to each of a plurality of imagings scheduled during a target period. The processing circuitry is configured to determine an imaging condition based on the allowable amount in the each of the plurality of imagings.

Abstract: According to one embodiment, a magnetic resonance imaging apparatus includes processing circuitry. The processing circuitry is configured to calculate an allowable amount of heat input to a superconducting magnet, the allowable amount being allocated to each of a plurality of imagings scheduled during a target period. The processing circuitry is configured to determine an imaging condition based on the allowable amount in the each of the plurality of imagings.

Abstract: According to one embodiment, a magnetic resonance imaging apparatus includes processing circuitry. The processing circuitry is configured to calculate an allowable amount of heat input to a superconducting magnet, the allowable amount being allocated to each of a plurality of imagings scheduled during a target period. The processing circuitry is configured to determine an imaging condition based on the allowable amount in the each of the plurality of imagings.

Abstract: According to one embodiment, a magnetic resonance imaging apparatus includes processing circuitry. The processing circuitry calculates a limit imaging condition based on one or more imaging parameters for determining an imaging condition, the limit imaging condition being an allowable limit relating to heat input to a superconducting magnet. The processing circuitry limits an input range of an imaging parameter input by an operator based on the limit imaging condition.

Abstract: According to at least one of embodiments, a magnetic resonance imaging apparatus includes a superconducting magnet configured to generate a static magnetic field; a cryocooler configured to cool down the superconducting magnet in a refrigeration cycle in which mechanical fluctuation with a predetermined period is included; a sequence controller configured to acquire magnetic resonance signals for generating a diagnostic image from an object; and processing circuitry configured to correct phase fluctuation included in the magnetic resonance signals for generating a diagnostic image acquired by the sequence controller, the phase fluctuation being generated by periodic fluctuation of the static magnetic field caused by mechanical fluctuation of the cryocooler.

Abstract: According to at least one of embodiments, a magnetic resonance imaging apparatus includes a superconducting magnet configured to generate a static magnetic field; a cryocooler configured to cool down the superconducting magnet in a refrigeration cycle in which mechanical fluctuation with a predetermined period is included; a sequence controller configured to acquire magnetic resonance signals for generating a diagnostic image from an object; and processing circuitry configured to correct phase fluctuation included in the magnetic resonance signals for generating a diagnostic image acquired by the sequence controller, the phase fluctuation being generated by periodic fluctuation of the static magnetic field caused by mechanical fluctuation of the cryocooler.

Abstract: A magnetic resonance imaging apparatus according to an embodiment includes a predicting unit and an imaging control unit. The predicting unit predicts a temperature change in a gradient coil at the time a pulse sequence is executed, based on temperature of the gradient coil and current waveform information on a gradient magnetic field pulse, before the pulse sequence is executed. The imaging control unit controls execution of the pulse sequence in accordance with a result of the prediction. The predicting unit predicts the temperature change by separating heat generation in the gradient coil into a component equivalent to heat generation as an electrical resistance of the gradient coil and a component equivalent to heat generation as an inductive circuit induced by switching of the gradient coil.

Abstract: In a magnetic resonance imaging apparatus according to an embodiment, a transmitting coil applies a radio-frequency magnetic field to a subject placed in a static magnetic field. A receiving coil receives a magnetic resonance signal emitted from the subject owing to an application of the radio-frequency magnetic field. A balun is connected to the receiving coil, and suppresses an unbalanced current induced in the receiving coil. An overheat protection circuit indicates that the balun is abnormal when a temperature of the balun exceeds a temperature threshold. An imaging control unit stops imaging when the overheat protection circuit indicates an abnormality of the balun.

Abstract: In a magnetic resonance imaging apparatus according to an embodiment, a transmitting coil applies a radio-frequency magnetic field to a subject placed in a static magnetic field. A receiving coil receives a magnetic resonance signal emitted from the subject owing to an application of the radio-frequency magnetic field. A balun is connected to the receiving coil, and suppresses an unbalanced current induced in the receiving coil. An overheat protection circuit indicates that the balun is abnormal when a temperature of the balun exceeds a temperature threshold. An imaging control unit stops imaging when the overheat protection circuit indicates an abnormality of the balun.

Abstract: In a magnetic resonance imaging apparatus according to an embodiment, a transmitting coil applies a radio-frequency magnetic field to a subject placed in a static magnetic field. A receiving coil receives a magnetic resonance signal emitted from the subject owing to an application of the radio-frequency magnetic field. A balun is connected to the receiving coil, and suppresses an unbalanced current induced in the receiving coil. An overheat protection circuit indicates that the balun is abnormal when a temperature of the balun exceeds a temperature threshold. An imaging control unit stops imaging when the overheat protection circuit indicates an abnormality of the balun.

Abstract: In a magnetic resonance imaging apparatus according to an embodiment, a transmitting coil applies a radio-frequency magnetic field to a subject placed in a static magnetic field. A receiving coil receives a magnetic resonance signal emitted from the subject owing to an application of the radio-frequency magnetic field. A balun is connected to the receiving coil, and suppresses an unbalanced current induced in the receiving coil. An overheat protection circuit indicates that the balun is abnormal when a temperature of the balun exceeds a temperature threshold. An imaging control unit stops imaging when the overheat protection circuit indicates an abnormality of the balun.

Abstract: Data is collected for average units including acquisition of template data and acquisition of imaging data. A frequency difference is calculated between a resonant frequency in a reference average unit and a resonant frequency of an object average unit based on phase variation of the magnetic field between the reference average unit and the object average unit. Corrected phase shift is produced in image data collected in one or more average units based on the frequency difference. An image is reconstructed based on the imaging data collected in the reference average unit and corrected imaging data concerning the object average unit constituted by one or more average units.

Abstract: A magnetic resonance imaging apparatus includes a phase difference calculation unit configured to perform a one-dimensional Fourier transform on complex data not phase-encoded extracted from complex data of a nuclear resonant signal collected by dynamic scanning, and determining a phase difference in time of data obtained by performing a one-dimensional Fourier transform on the complex data not phase-encoded. A correction unit is configured to correct for non-uniformity of static magnetic field caused during the dynamic scanning, depending upon the phase difference.

Abstract: A magnetic resonance imaging apparatus performs photographing by magnetic resonance imaging using hardware of which temperature is likely to rise due to a photographing operation. The magnetic resonance imaging apparatus includes an obtaining device, an alert state detecting device, and a control device. The obtaining device obtains information providing an indication of temperature of the hardware during the photographing. The alert state detecting device detects the occurrence of an alert state where the temperature of the hardware is likely to rise enough to affect the photographing, on the basis of the obtained information. The control device controls the photographing so as to suppress temperature rise of the hardware according to the detection of the occurrence of the alert state.

Abstract: A magnetic resonance imaging apparatus performs photographing by magnetic resonance imaging using hardware of which temperature is likely to rise due to a photographing operation. The magnetic resonance imaging apparatus includes an obtaining device, an alert state detecting device, and a control device. The obtaining device obtains information providing an indication of temperature of the hardware during the photographing. The alert state detecting device detects the occurrence of an alert state where the temperature of the hardware is likely to rise enough to affect the photographing, on the basis of the obtained information. The control device controls the photographing so as to suppress temperature rise of the hardware according to the detection of the occurrence of the alert state.

Abstract: A method includes collecting data for average units including acquisition of template data and acquisition of imaging data, calculating a frequency difference between a resonant frequency in a reference average unit and a resonant frequency of an object average unit based on a phase variation of the magnetic field in a period where the template data is collected in the reference average unit and a phase variation of the magnetic resonance signal in a period where the template data is collected in the object average unit, correcting a phase shift produced in image data collected in the object average unit constituted by one or more average units based on the frequency difference, and reconstructing an image concerning the subject based on the imaging data collected in the reference average unit and the corrected imaging data concerning the object average unit constituted by one or more average units.

Abstract: A magnetic resonance imaging apparatus 20 includes a phase difference calculation unit 44 configured to perform a one-dimensional Fourier transform on complex data not phase-encoded extracted from complex data of a nuclear resonant signal collected by dynamic scanning, and determining a phase difference in time of data obtained by performing a one-dimensional Fourier transform on the complex data not phase-encoded, and a correction unit 50, 51 configured to correct for a non-uniformity of static magnetic field caused during the dynamic scanning, depending upon the phase difference.

Abstract: A magnetic resonance imaging apparatus 20 includes a phase difference calculation unit 44 configured to perform a one-dimensional Fourier transform on complex data not phase-encoded extracted from complex data of a nuclear resonant signal collected by dynamic scanning, and determining a phase difference in time of data obtained by performing a one-dimensional Fourier transform on the complex data not phase-encoded, and a correction unit 50, 51 configured to correct for a non-uniformity of static magnetic field caused during the dynamic scanning, depending upon the phase difference.

Abstract: A magnetic resonance imaging apparatus includes a phased array coil including a plurality of local coils, a pre-scanning unit which pre-scans, before image scanning, an area including at least part of an image scanning area, a determination unit which determines whether each of the local coils is abnormal, based on signals output from the local coils during pre-scanning, and an information supply unit which supplies a user with information indicating an abnormal local coil, if the determination unit determines that the local coils include the abnormal local coil.

Abstract: A magnetic resonance imaging apparatus includes a phased array coil including a plurality of local coils, a pre-scanning unit which pre-scans, before image scanning, an area including at least part of an image scanning area, a determination unit which determines whether each of the local coils is abnormal, based on signals output from the local coils during pre-scanning, and an information supply unit which supplies a user with information indicating an abnormal local coil, if the determination unit determines that the local coils include the abnormal local coil.