MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD

• US 20140009157A1
• Filed: 09/10/2013
• Published: 01/09/2014
• Est. Priority Date: 09/22/2011
• Status: Active Grant

• Current Assignee: Toshiba Medical Systems Corporation (Canon Inc.)
• Original Assignee: Toshiba Medical Systems Corporation (Canon Inc.), Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: UMEDA, Masaaki
• Granted Patent: US 9,018,953 B2
• Time in Patent Office: Days
• US Class Current: 324/309
• CPC Class Codes: G01R 33/54 Signal processing systems, e.g. using pulse sequences ; Generation or control of pulse sequences; Operator console
• CPC Class Codes: G01R 33/5602 by filtering or weighting based on different relaxation times within the sample, e.g. T1 weighting using an inversion pulse
• CPC Class Codes: G01R 33/5617 using RF refocusing, e.g. RARE

Abstract

According to one embodiment, a magnetic resonance imaging apparatus includes a data acquiring unit and an image generating unit. The data acquiring unit is configured to acquire a signal train of magnetic resonance signals from an object by a spin echo method for applying a refocus pulse repeatedly following an excitation pulse with changing a flip angle of the refocus pulse. The image generating unit is configured to generate frames of image data having mutually different contrasts, based on mutually different portions of the signal train of the magnetic resonance signals.

Claims

1. A magnetic resonance imaging apparatus comprising:

a data acquiring unit configured to acquire a signal train of magnetic resonance signals from an object by a spin echo method for applying a refocus pulse repeatedly following an excitation pulse with changing a flip angle of the refocus pulse; and

an image generating unit configured to generate frames of image data having mutually different contrasts, based on mutually different portions of the signal train of the magnetic resonance signals.

3. A magnetic resonance imaging apparatus of claim 1,

wherein said data acquiring unit is configured to apply the refocus pulse repeatedly along a discontinuous sweep pattern representing a change of the flip angle appropriate for echo times corresponding to the frames of the image data, the discontinuous sweep pattern having local minimal values of which the number is according to the number of the frames of the image data.

4. A magnetic resonance imaging apparatus of claim 1,

wherein said data acquiring unit is configured to apply the refocus pulse repeatedly along a sweep pattern representing a change of the flip angle appropriate for echo times corresponding to the frames of the image data.

5. A magnetic resonance imaging apparatus of claim 4, further comprising:

a storage unit configured to store sweep patterns of the flip angle appropriate for respective combinations of echo times,

wherein said data acquiring unit is configured to acquire a sweep pattern of the flip angle, related with the echo times corresponding to the frames of the image data, from said storage unit.

6. A magnetic resonance imaging apparatus of claim 4,

wherein said data acquiring unit is configured to calculate a sweep pattern of the flip angle for acquiring the portions of the signal train of the magnetic resonance signals with stable intensities, the portions being for generating the frames of the image data.

7. A magnetic resonance imaging apparatus of claim 1,

wherein said image generating unit is configured to generate proton density image data and transverse relaxation weighted image data as the frames of the image data.

2. A magnetic resonance imaging apparatus comprising:

a data acquiring unit configured to acquire a signal train of magnetic resonance signals from an object by a spin echo method for applying a refocus pulse repeatedly following an excitation pulse with changing a flip angle of the refocus pulse, along a sweep pattern representing a change of the flip angle appropriate for mutually different contrasts; and

an image generating unit configured to generate frames of image data having the different contrasts, based on mutually different portions of the signal train of the magnetic resonance signals.

8. A magnetic resonance imaging method comprising:

acquiring a signal train of magnetic resonance signals from an object by a spin echo method for applying a refocus pulse repeatedly following an excitation pulse with changing a flip angle of the refocus pulse; and

generating frames of image data having mutually different contrasts, based on mutually different portions of the signal train of the magnetic resonance signals.