Patent ID: 9041394
Filing Date: 2015-05-26
Classification: G01R

Abstract:
1. A magnetic resonance imaging (MRI) apparatus comprising: an MRI gantry including static and gradient magnetic field generators, at least one radio frequency (RF) coil coupled to an imaging volume, RF transmitter and RF receiver circuits coupled to said at least one RF coil; a magnetic resonance pulse sequence processor; and a memory that stores processor-executable instructions that, when executed by the magnetic resonance pulse sequence processor, cause the magnetic resonance pulse sequence processor to: execute a first pulse sequence in which no gradient magnetic field is applied in a readout direction, at least one gradient pulse is applied in a phase encoding direction and wherein a plurality of sampling gradient magnetic fields are applied in a phase encoding direction during readout of NMR echo signals, wherein the at least one gradient pulse is either (a) a pre-dephasing gradient magnetic field or (b) gradient magnetic fields applied before and after the sampling gradient magnetic fields; execute a second pulse sequence in which no gradient magnetic field is applied in said readout direction wherein the plurality of sampling gradient magnetic fields in said phase encoding direction are applied at the same echo signal locations as those in the first pulse sequence, and representative phase encoding gradient magnetic fields, selected from those among phase encoding gradient magnetic fields applied in a main pulse sequence and used in acquiring an image with the magnetic resonance imaging apparatus, are applied; calculate as the amount of correction, the amount of phase difference which occurs in the phase encoding direction as a result of the applied phase encoding gradient magnetic fields, based on a phase difference between a plurality of echo signals collected by the first pulse sequence and a phase difference between a plurality of echo signals collected by the second pulse sequence; correct the main pulse sequence on the basis of the calculated amount of correction; and execute the corrected main pulse sequence in order to perform phase corrected magnetic resonance imaging with the magnetic resonance imaging apparatus.