MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD

摘要

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.

主权项

1. A magnetic resonance imaging apparatus comprising:
a gradient coil configured to apply a gradient magnetic field in accordance with a pulse sequence; an RF coil configured to transmit RF pulses causing nuclear magnetic resonance and receive nuclear magnetic resonance signals in accordance with the pulse sequence; an RF receiver configured to acquire the nuclear magnetic resonance signals received by the RF coil in accordance with the pulse sequence; and processing circuitry configured to control the gradient coil, the RF coil, and the RF receiver to perform a first pulse sequence, a second pulse sequence, and a main-scan pulse sequence, wherein the processing circuitry is configured to (a) set the first pulse sequence in which application of a gradient magnetic field in a readout direction is included, in such a manner that the nuclear magnetic resonance signals are acquired from a first acquisition region including at least a part of an imaging region of a main scan, (b) set the second pulse sequence in which application of the gradient magnetic field in the readout direction is included, in such a manner that the nuclear magnetic resonance signals are acquired from a second acquisition region including at least a part of the imaging region and being shifted from the first acquisition region, (c) set the main-scan pulse sequence in which application of the gradient magnetic field in the readout direction and a gradient magnetic field in a phase encode direction is included, in such a manner that the nuclear magnetic resonance signals from the imaging region are acquired, (d) generate first k-space data including a plurality of matrix elements, by sampling the nuclear magnetic resonance signals acquired by the first pulse sequence, (e) generate second k-space data including a plurality of matrix elements, by sampling the nuclear magnetic resonance signals acquired by the second pulse sequence, (f) calculate phase difference data indicative of phase difference in the readout direction between the first k-space data and the second k-space data, (g) generate main scan k-space data based on the nuclear magnetic resonance signals acquired by the main-scan pulse sequence and the phase difference data, and (h) reconstruct image data of the imaging region based on the main scan k-space data.