Magnetic resonance imaging apparatus and synchronous measurement method

摘要

An image with a desired contrast is obtained while suppressing body motion artifacts caused by both random motion and periodic motion of an object. In order to do so, an imaging sequence using a non-Cartesian sampling method is executed so as to synchronize with a biological signal only at the start time and a repetition time (TR), which is an execution interval between shots within the imaging sequence, is maintained. In addition, a time difference between a delay time and a start time of each shot is calculated, and a shot with a predetermined time difference or more is executed again after the TR time.

主权项

1. A magnetic resonance imaging apparatus comprising:
an imaging control unit that repeats an imaging sequence, in which one or more echo signals corresponding to a partial region of a measurement space are collected, at predetermined repetition time (TR) intervals on the basis of a non-Cartesian sampling method while changing the partial region; and a biological signal receiving unit that receives a plurality of periodic biological signals of an object, wherein based on one biological signal amongst the plurality of periodic biological signals received by the biological signal receiving unit the imaging control unit starts and repeats the imaging sequence at the same repetition time (TR) intervals after a predetermined delay time from the one biological signal, wherein the biological signal receiving unit includes a biological signal receiving time storage unit which stores a corresponding receiving time as a biological signal receiving time whenever a biological signal is received while the imaging control unit is executing the imaging sequence, and the imaging control unit includes a time difference calculating unit which calculates a minimum value of a time between a start time of a corresponding shot and a delay time after elapse of the delay time from each biological signal receiving time, as a time difference, in each shot and an adoption determining unit which determines that an echo signal collected in a corresponding shot is not adopted when the time difference exceeds a threshold value set in advance, and executes again the shot determined not to be adopted by the adoption determining unit after the repetition time elapses from the start of the shot.