MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD

• US 20120161760A1
• Filed: 03/12/2012
• Published: 06/28/2012
• Est. Priority Date: 11/04/2010
• Status: Active Grant

• Current Assignee: Toshiba Medical Systems Corporation (Canon Inc.)
• Original Assignee: Toshiba Medical Systems Corporation (Canon Inc.)
• Inventors: KUHARA, Shigehide
• Granted Patent: US 9,594,138 B2
• Time in Patent Office: Days
• US Class Current: 324/307
• CPC Class Codes: A61B 2576/023 for the heart
• CPC Class Codes: A61B 5/0037 Performing a preliminary scan, e.g. a prescan for identifying a region of interest
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: G01R 33/50 based on the determination of relaxation times , e.g. T1 measurement by IR sequences; T2 measurement by multiple-echo sequences
• CPC Class Codes: G01R 33/543 Control of the operation of the MR system, e.g. setting of acquisition parameters prior to or during MR data acquisition, dynamic shimming, use of one or more scout images for scan plane prescription G01R33/546 takes precedence
• 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: G16H 30/40 for processing medical images, e.g. editing

Abstract

A magnetic resonance imaging apparatus according to an embodiment includes a calculation unit and an imaging unit. The calculation unit calculates an inversion time for imaging by analyzing frames of image data or magnetic resonance signals acquired from an object. The frames of the image data or the magnetic resonance signals are acquired in response to inversion times which are different with each other and set based on a inversion recovery method. The imaging unit performs the imaging under the inversion recovery method using the inversion time calculated for the imaging.

Claims

1. A magnetic resonance imaging apparatus comprising:

a calculation unit configured to calculate an inversion time for imaging by analyzing frames of image data or magnetic resonance signals acquired from an object, the frames of the image data or the magnetic resonance signals being acquired in response to inversion times which are different with each other and set based on a inversion recovery method; and

an imaging unit configured to perform the imaging under the inversion recovery method using the inversion time calculated for the imaging.

2. A magnetic resonance imaging apparatus of claim 1, wherein said calculation unit is configured to calculate an inversion time, as the inversion time for the imaging, which is given when a curve obtained by applying curve fitting to the frames of the image data or the magnetic resonance signals acquired responsively to the inversion times becomes zero.

3. A magnetic resonance imaging apparatus of claim 1, further comprising

a substance specifying unit configured to enable a display unit to display at least one of a Ti value obtained through the curve fitting, the inversion time given when the curve becomes zero, a shape of the curve, and information indicating a substance estimated based on the T1 value.

4. A magnetic resonance imaging apparatus of claim 1,

wherein said imaging unit is configured to perform cardiac delayed enhancement imaging or non-enhancement blood flow imaging.

5. A magnetic resonance imaging apparatus of claim 2,

wherein said calculation unit is configured to calculate inversion times given when values of curves resulting from regions of interest become zero respectively to adopt a longest inversion time out of the inversion times resulting from the regions of interest as the inversion time for the imaging.

6. A magnetic resonance imaging apparatus of claim 2,

wherein said imaging unit is configured to sequentially perform both the imaging and acquisition of the frames of the image data or the magnetic resonance signals obtained in response to the inversion times.

7. A magnetic resonance imaging apparatus of claim 2,

wherein said calculation unit is configured to perform the curve fitting by using real-part signals of frames of image data obtained after phase correction and corresponding to the inversion times or real-part signals of magnetic resonance signals obtained through local excitation, after phase correction, and corresponding to the inversion times.

8. A magnetic resonance imaging apparatus of claim 2,

wherein said calculation unit is configured to perform phase correction with absolute-value image signals corresponding to the inversion times to perform the curve fitting using image signals obtained by correcting polarities of absolute-value image signals obtained after the phase correction.

9. A magnetic resonance imaging apparatus of claim 2,

wherein the calculation unit is configured to

obtain a first curve by the curve fitting with first image signals obtained by inverting polarities of absolute-value image signals each acquired in response to an inversion time shorter than an inversion time corresponding to a minimum value of absolute-value image signals acquired in response to the inversion times,

obtain a second curve by the curve fitting with second image signals obtained by inverting a polarity of an absolute-value image signal corresponding to the minimum value and respective polarities of the absolute-value image signals each obtained responsive to the inversion time shorter than the inversion time corresponding to the minimum value, and

adopt a curve approximated best by the curve fitting.

10. A magnetic resonance imaging apparatus comprising:

a calculation unit configured to calculate a formula of a curve obtained by curve fitting applied to frames of image data or magnetic resonance signals acquired responsively to inversion times which are different with each other and set based on a recovery method; and

a substance specifying unit configured to enable a display unit to display at least one of a T1 value obtained through the curve fitting, the inversion time given when the curve becomes zero, a shape of the curve, and information indicating a substance estimated based on the T1 value.

11. A magnetic resonance imaging method comprising:

calculating an inversion time for imaging by analyzing frames of image data or magnetic resonance signals acquired from an object, the frames of the image data or the magnetic resonance signals being acquired in response to inversion times which are different with each other and set based on a inversion recovery method; and

performing the imaging under the inversion recovery method using the inversion time calculated for the imaging.