Magnetic resonance imaging apparatus and method of controlling the same
AssigneeFUJIFILM Healthcare Corporation
InventorsKosuke Ito, Atsushi Kuratani
Life of this patent
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Abstract
Generation of artifacts caused by the FID signal is suppressed even when the parallel imaging is applied to the imaging using a spin echo type pulse sequence. In performing a pulse sequence of a spin echo type using an excitation RF pulse for exciting nuclear spin and an inversion RF pulse for inverting excited nuclear spin as a high-frequency magnetic field pulse, a high-frequency transmitter of a MRI apparatus changes the phase of the inversion RF pulse according to the phase encoding and the phase encoding number imparted for each echo signal. Specifically, the phase of the inversion RF pulse is controlled to be a quadratic function of the phase encode of the echo signal.
Claims10
A magnetic resonance imaging apparatus comprising:
- a static magnetic field generating magnet for generating a static magnetic field;
- a high-frequency transmitting unit for irradiating an RF pulse to a subject placed in a static magnetic field space;
- a receiving unit for receiving an echo signal generated from the subject;
- a gradient magnetic field generating unit for generating a gradient magnetic field for encoding the echo signal;
- a control unit for controlling the high-frequency transmitting unit, the receiving unit and the gradient magnetic field generating unit according to a predetermined pulse sequence;
- and an arithmetic unit for image reconstruction using the echo signal,
- wherein in irradiating while using a pulse sequence of a spin echo system including irradiation of an excited RF pulse for exciting nuclear spin and irradiation of inversion RF pulses for inverting the excited nuclear spin as the pulse sequence, the high-frequency transmission unit changes an irradiation phase of each inversion RF pulse of the pulse sequence of the spin echo system that is to be irradiated after a predetermined repetition time TR from spin excitation, according to phase encode imparted for the echo signal and a phase encoding number, the irradiation phase of said each inversion RF pulse to be irradiated after the predetermined repetition time TR from the spin excitation being represented by a quadratic function of the phase encode.
A method of controlling a magnetic resonance imaging apparatus, comprising:
- performing a spin echo type pulse sequence which includes irradiation of RF pulses exciting nuclear spin and irradiation of inversion RF pulses inverting excited nuclear spin;
- and
- changing an irradiation phase of each inversion RF pulse of the inversion RF pulses after a predetermined repetition time TR from spin excitation, according to a phase encode imparted for each echo signal and a phase encoding number, the irradiation phase of said each inversion RF pulse being represented by a quadratic function of the phase encode.
Dependencies are inferred from the claim text.