MAGNETIC RESONANCE IMAGING APPARATUS AND MAGNETIC RESONANCE IMAGING METHOD

• US 20090148021A1
• Filed: 12/09/2008
• Published: 06/11/2009
• Est. Priority Date: 12/10/2007
• 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: YUI, Masao
• Granted Patent: US 8,417,007 B2
• Time in Patent Office: Days
• US Class Current: 382/131
• CPC Class Codes: G01R 33/56308 Characterization of motion or flow; Dynamic imaging
• CPC Class Codes: G01R 33/56316 involving phase contrast techniques

Abstract

A magnetic resonance imaging apparatus includes a data acquisition unit, a correction unit, a sorting unit and n image reconstruction unit. The data acquires data for imaging and projection data. The correction unit performs motion correction of the data using the breath levels obtained based on the projection data. The data sorting unit sorts the data after the motion correction into a cardiac time phase order based on electrocardiographic information. The image reconstruction unit reconstructs three dimensional image data based on the sorted data after the motion correction.

Claims

1. A magnetic resonance imaging apparatus comprising:

a data acquisition unit configured to acquire plural pieces of data for imaging and plural pieces of projection data for obtaining breath levels of an object respectively from the object by continuously applying a radio frequency pulse train to the object with a constant interval;

a correction unit configured to perform motion correction of the plural pieces of the data with using the breath levels of the object obtained based on the plural pieces of the projection data;

a data sorting unit configured to sort the plural pieces of the data after the motion correction into a cardiac time phase order based on electrocardiographic information of the object; and

an image reconstruction unit configured to reconstruct three dimensional image data based on the plural pieces of the data sorted in the cardiac time phases after the motion correction.

3. A magnetic resonance imaging apparatus of claim 1,

wherein said data acquisition unit is configured to apply gradient magnetic fields to the object so as to share a common gradient magnetic field pulse with imaging parts for acquiring the plural pieces of the data for imaging and projection parts for acquiring the plural pieces of the projection data.

4. A magnetic resonance imaging apparatus of claim 1,

wherein said data acquisition unit is configured to apply the radio frequency pulse train to the object so as to share a common radio frequency pulse with imaging parts for acquiring the plural pieces of the data for imaging and projection parts for acquiring the plural pieces of the projection data.

5. A magnetic resonance imaging apparatus of claim 1,

wherein said data acquisition unit is configured to acquire the plural pieces of the data separately to plural segments set in k space and plural pieces of projection data respectively corresponding to the plural segments.

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

a data extracting unit configured to extract pieces of data each acquired in a state where a breath level of the object is within a range defined by a predetermined threshold from the plural pieces of data,

wherein said image reconstruction unit is configured to reconstruct the three dimensional image data based on extracted pieces of the data sorted in the cardiac time phases after the motion correction.

7. A magnetic resonance imaging apparatus of claim 1,

wherein said data acquisition unit is configured to acquire the pieces of the data with using a pulse sequence which is able to acquire projection data representing the electrocardiographic information of the object, and

said data sorting unit is configured to sort the pieces of the data in the cardiac time phases based on the electrocardiographic information detected from the projection data.

8. A magnetic resonance imaging apparatus of claim 1,

wherein said data acquisition unit is configured to acquire the pieces of the data with using a Steady-state Free Precession sequence for applying the radio frequency pulse train to the object so as to keep a steady state of a magnetization in the object.

9. A magnetic resonance imaging apparatus of claim 1,

wherein said correction unit is configured to perform the motion correction during acquisition of the plural pieces of the data for imaging and the plural pieces of the projection data.

2. A magnetic resonance imaging apparatus comprising:

a data acquisition unit configured to acquire plural pieces of data for imaging and plural pieces of projection data for obtaining breath levels of an object respectively from the object by continuously applying a radio frequency pulse train to the object with a constant interval;

a data sorting unit configured to sort the plural pieces of the data into a cardiac time phase order based on electrocardiographic information of the object;

a correction unit configured to perform motion correction of the plural pieces of the data sorted in the cardiac time phases with using the breath levels of the object obtained based on the plural pieces of the projection data; and

an image reconstruction unit configured to reconstruct three dimensional image data based on the plural pieces of the data sorted in the cardiac time phases after the motion correction.

10. A magnetic resonance imaging method apparatus comprising:

acquiring plural pieces of data for imaging and plural pieces of projection data for obtaining breath levels of an object respectively from the object by continuously applying a radio frequency pulse train to the object with a constant interval;

performing motion correction of the plural pieces of the data with using the breath levels of the object obtained based on the plural pieces of the projection data;

sorting the plural pieces of the data after the motion correction into a cardiac time phase order based on electrocardiographic information of the object; and

reconstructing three dimensional image data based on the plural pieces of the data sorted in the cardiac time phases after the motion correction.

12. A magnetic resonance imaging method of claim 10,

wherein gradient magnetic fields are applied to the object so as to share a common gradient magnetic field pulse with imaging parts for acquiring the plural pieces of the data for imaging and projection parts for acquiring the plural pieces of the projection data.

13. A magnetic resonance imaging method of claim 10,

wherein the radio frequency pulse train is applied to the object so as to share a common radio frequency pulse with imaging parts for acquiring the plural pieces of the data for imaging and projection parts for acquiring the plural pieces of the projection data.

14. A magnetic resonance imaging method of claim 10,

wherein the plural pieces of the data are acquired separately to plural segments set in k space and plural pieces of projection data respectively corresponding to the plural segments are acquired.

15. A magnetic resonance imaging method of claim 10, further comprising:

extracting pieces of data each acquired in a state where a breath level of the object is within a range defined by a predetermined threshold from the plural pieces of data,

wherein the three dimensional image data is reconstructed based on extracted pieces of the data sorted in the cardiac time phases after the motion correction.

16. A magnetic resonance imaging method of claim 10,

wherein the pieces of the data are acquired with using a pulse sequence which is able to acquire projection data representing the electrocardiographic information of the object, and

the pieces of the data are sorted in the cardiac time phases based on the electrocardiographic information detected from the projection data.

17. A magnetic resonance imaging method of claim 10,

wherein the pieces of the data are acquired with using a Steady-state Free Precession sequence for applying the radio frequency pulse train to the object so as to keep a steady state of a magnetization in the object.

18. A magnetic resonance imaging method of claim 10,

wherein the motion correction is performed during acquisition of the plural pieces of the data for imaging and the plural pieces of the projection data.

11. A magnetic resonance imaging method apparatus comprising:

acquiring plural pieces of data for imaging and plural pieces of projection data for obtaining breath levels of an object respectively from the object by continuously applying a radio frequency pulse train to the object with a constant interval;

sorting the plural pieces of the data into a cardiac time phase order based on electrocardiographic information of the object;

performing motion correction of the plural pieces of the data sorted in the cardiac time phases with using the breath levels of the object obtained based on the plural pieces of the projection data; and

reconstructing three dimensional image data based on the plural pieces of the data sorted in the cardiac time phases after the motion correction.