IMAGE PROCESSING APPARATUS, MAGNETIC RESONANCE IMAGING APPARATUS, AND IMAGE PROCESSING METHOD

• US 20100087730A1
• Filed: 10/02/2009
• Published: 04/08/2010
• Est. Priority Date: 10/03/2008
• Status: Active Grant

• Current Assignee: Toshiba Medical Systems Corporation (Canon Inc.), Tokai University Educational System
• Original Assignee: Toshiba Medical Systems Corporation (Canon Inc.), Tokai University Educational System
• Inventors: Yamada, Shinya, Kanazawa, Hitoshi
• Granted Patent: US 8,903,469 B2
• Time in Patent Office: Days
• US Class Current: 600/419
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• 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 33/5608 Data processing and visualization specially adapted for MR, e.g. for feature analysis and pattern recognition on the basis of measured MR data, segmentation of measured MR data, edge contour detection on the basis of measured MR data, for enhancing measured MR data in terms of signal-to-noise ratio by means of noise filtering or apodization, for enhancing measured MR data in terms of resolution by means for deblurring, windowing, zero filling, or generation of gray-scaled images, colour-coded images or images displaying vectors instead of pixels image data processing or generation, in general G06T
• CPC Class Codes: G01R 33/5616 using gradient refocusing, e.g. EPI
• CPC Class Codes: G01R 33/5617 using RF refocusing, e.g. RARE
• CPC Class Codes: G01R 33/56316 involving phase contrast techniques
• CPC Class Codes: G06T 2207/10088 Magnetic resonance imaging [MRI]
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 2207/30016 Brain
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 7/277 involving stochastic approaches, e.g. using Kalman filters

Abstract

A velocity-image creating unit creates a velocity image that indicates a distribution of velocity components with respect to each of a plurality of images obtained by repeating a plurality of number of times Echo Planar Imaging (EPI) that is capable of obtaining velocity components of a Cerebrospinal Fluid (CSF) flowing inside a subject. A velocity-variance image creating unit calculates variance of velocity components along the time sequence by same position on velocity images by using a plurality of created velocity images. A superimposed-image processing unit then superimposes the distribution of the variance of the velocity components according to the velocity-variance image on an average absolute-value image, and an image display unit displays a superimposed image.

Claims

1. An image processing apparatus comprising:

a calculation-image creating unit that creates a calculation image including velocity components of a Cerebrospinal Fluid (CSF) flowing inside a subject with respect to each of a plurality of images obtained by repeating imaging a plurality of number of times according to an imaging method capable of obtaining the velocity components;

a statistic-image creating unit that calculates statistics indicating velocity variation of the CSF by same position on calculation images by using a plurality of calculation images created by the calculation-image creating unit, and creates a statistic image indicating a distribution of calculated statistics;

a statistics display unit that displays the distribution of the statistics according to the statistic image created by the statistic-image creating unit.

2. The apparatus according to claim 1, wherein

the calculation-image creating unit creates a velocity image indicating a distribution of the velocity components as the calculation image, and

the statistic-image creating unit calculates variance of the velocity components along a time sequence as the statistics.

3. The apparatus according to claim 1, wherein the imaging method is a method of obtaining the images by repeating flow imaging of collecting a group of echo signals required for reconstructing one image with one excitation pulse by a magnetic resonance imaging apparatus.

4. The apparatus according to claim 2, wherein the imaging method is a method of obtaining the images by repeating flow imaging of collecting a group of echo signals required for reconstructing one image with one excitation pulse by a magnetic resonance imaging apparatus.

5. The apparatus according to claim 1, wherein the imaging method is a method that is capable of reconstructing one image with one excitation pulse and giving a phase shift proportional to a velocity onto reconstructed image, by a magnetic resonance imaging apparatus.

6. The apparatus according to claim 2, wherein the imaging method is a method that is capable of reconstructing one image with one excitation pulse and giving a phase shift proportional to a velocity onto reconstructed image, by a magnetic resonance imaging apparatus.

7. The apparatus according to claim 1, wherein

the calculation-image creating unit creates an absolute-value image indicating a distribution of signal strengths as the calculation image, and

the statistic-image creating unit calculates variance of the signal strengths along a time sequence as the statistics.

8. The apparatus according to claim 1, wherein

the imaging method is a method of labeling a certain region in a scan cross section by applying one of an inversion excitation pulse and a saturation excitation pulse, and reconstructing an image by detecting a signal of a CSF flowing out from the region, by a magnetic resonance imaging apparatus, and

the statistic-image creating unit calculates variance of signal strengths based on signal values of the CSF.

9. The apparatus according to claim 7, wherein

the imaging method is a method of labeling a certain region in a scan cross section by applying one of an inversion excitation pulse and a saturation excitation pulse, and reconstructing an image by detecting a signal of a CSF flowing out from the region, by a magnetic resonance imaging apparatus, and

the statistic-image creating unit calculates variance of signal strengths based on signal values of the CSF.

10. The apparatus according to claim 1, wherein the statistic-image creating unit calculates, as the statistics, one of a maximum value and a minimum value of velocity components by same position an calculation images.

11. The apparatus according to claim 1, wherein the statistic-image creating unit calculates, as the statistics, an average value of velocity components within a certain proportion from a top of all velocity components when the velocity components are listed in descending order of value by same position on calculation images.

12. The apparatus according to claim 1, wherein a plurality of images to be used by the calculation-image creating unit are obtained by repeating the imaging a plurality of number of times in a synchronized manner with a biological signal of the subject.

13. The apparatus according to claim 2, wherein a plurality of images to be used by the calculation-image creating unit are obtained by repeating the imaging a plurality of number of times in a synchronized manner with a biological signal of the subject.

14. The apparatus according to claim 1, wherein a plurality of images to be used by the calculation-image creating unit are obtained by repeating the imaging a plurality of number of times in a certain cycle.

15. The apparatus according to claim 1, wherein the statistics display unit displays the distribution of the statistics by superimposing on a certain calculation image.

16. The apparatus according to claim 1, wherein the statistics display unit changes a display mode of the distribution of the statistics in accordance with a value of the statistics.

17. The apparatus according to claim 1, wherein the statistics display unit changes a display mode of the distribution of the statistics in accordance with a flowing direction of the CSF.

18. A magnetic resonance imaging apparatus comprising:

a calculation-image creating unit that creates a calculation image including velocity components of a Cerebrospinal Fluid (CSF) flowing inside a subject with respect to each of a plurality of images obtained by repeating imaging a plurality of number of times according to an imaging method capable of obtaining the velocity components;

a statistic-image creating unit that calculates statistics indicating velocity variation of the CSF by same position on calculation images by using a plurality of calculation images created by the calculation-image creating unit, and creates a statistic image indicating a distribution of calculated statistics;

a statistics display unit that displays the distribution of the statistics according to the statistic image created by the statistic-image creating unit.

19. A magnetic resonance imaging apparatus comprising:

an imaging processing unit that performs flow imaging of acquiring a group of echo signals required for reconstructing one image with one excitation pulse with respect to an imaging region including a CSF, each time when a certain delay time elapses from each trigger signal that appears repeatedly;

an image creating unit that creates a plurality of CSF images based on each group of echo signals obtained by the flow imaging performed by the imaging processing unit; and

a display unit that continuously displays the CSF images created by the image creating unit.

20. An image processing method comprising:

creating a calculation image including velocity components of a CSF flowing inside a subject with respect to each of a plurality of images obtained by repeating imaging a plurality of number of times according to an imaging method capable of obtaining the velocity components;

calculating statistics indicating velocity variation of the CSF by same position on calculation images by using a plurality of created calculation images, and creating a statistic image indicating a distribution of calculated statistics; and

displaying the distribution of the statistics according to the statistic image.