Image processing apparatus and X-ray diagnosis apparatus

• US 10,453,184 B2
• Filed: 03/02/2015
• Issued: 10/22/2019
• Est. Priority Date: 02/28/2014
• Status: Active Grant

• Current Assignee: Canon Medical Systems Corporation (Canon Inc.)
• Original Assignee: Canon Medical Systems Corporation (Canon Inc.)
• Inventors: Ohishi, Satoru
• Primary Examiner(s): Youssef, Menatoallah
• Application Number:
  US14/635,421
• Publication Number:
  US 20150248757A1
• Time in Patent Office: 1,695 Days
• CPC Class Codes: G06T 2207/10081 Computed x-ray tomography [CT]
• CPC Class Codes: G06T 2207/10088 Magnetic resonance imaging [MRI]
• CPC Class Codes: G06T 2207/10116 X-ray image
• CPC Class Codes: G06T 2207/10132 Ultrasound image
• CPC Class Codes: G06T 2207/20012 Locally adaptive
• CPC Class Codes: G06T 2207/20182 Noise reduction or smoothing in the temporal domain; Spatio-temporal filtering
• CPC Class Codes: G06T 2207/30101 Blood vessel; Artery; Vein; Vascular
• CPC Class Codes: G06T 5/70 Denoising; Smoothing
• CPC Class Codes: G06T 7/11 Region-based segmentation

Abstract

An image processing apparatus includes an identification unit, a calculator, and an image processor. The identification unit identifies a group of pixels indicating an object of interest in medical image data. The calculator specifies a cross-section corresponding to the running direction of the object of interest indicated by the group of pixels in the medical image data. The image processor performs noise reduction on the cross-section identified.

Claims

1. An image processing apparatus, comprising:

processing circuitry configured to

identify a group of pixels corresponding to a particular blood vessel as an object of interest in medical image data;

determine pixels defining a particular cross-section projected correspondingly to a running direction of the particular blood vessel and selected from among a plurality of cross-sections having different directions, based on the group of pixels being projected onto each of the plurality of cross-sections having the different directions; and

perform noise reduction on the determined pixels defining the particular cross-section to obtain the determined pixels defining the particular cross-section having less noise.

2. The image processing apparatus of claim 1, wherein the processing circuitry is further configured to compare a portion corresponding to the particular blood vessel with a predetermined diameter, specify a part of the portion having a diameter smaller than the predetermined diameter, and obtain a running direction of the specified part.

3. The image processing apparatus of claim 1, wherein the processing circuitry is further configured to

minimize the medical image data to remove a small diameter blood vessel from a blood vessel as the object of interest, and

obtain a difference between images before and after removal of the small diameter blood vessel to obtain the small diameter blood vessel.

4. The image processing apparatus of claim 1, wherein the processing circuitry is further configured to

specify a plurality of blood vessels and obtain a diameter of each of the specified blood vessels, and

specify the particular blood vessel as the object of interest from among the plurality of blood vessels, the particular blood vessel having a diameter equal to or smaller than a threshold.

5. The image processing apparatus of claim 1, wherein the processing circuitry is further configured to obtain a vector for each of predetermined segments of the particular blood vessel, and obtain a summation of vectors of the segments to determine the cross-section.

6. The image processing apparatus of claim 5, wherein the processing circuitry is configured to obtain the vector, which is a unit vector.

7. The image processing apparatus of claim 5, wherein the processing circuitry is further configured to obtain a diameter of the particular blood vessel based on the group of pixels corresponding to the particular blood vessel, and change a length of the segments used for calculation of the vectors based on the diameter of the particular blood vessel.

8. The image processing apparatus of claim 1, wherein the processing circuitry is further configured to

obtain a matching rate between a pixel value of a target pixel to which the noise reduction is applied and a pixel value of each of peripheral pixels around the target pixel, and determine a weight of each of the peripheral pixels according to the matching rate,

obtain a weighted average of the peripheral pixels based on the determined weight, and

obtain the pixel value of the target pixel based on the matching rate and the weighted average.

9. The image processing apparatus of claim 1, wherein

the medical image data is acquired based on an acquisition program for acquiring the medical image data, and

the processing circuitry is further configured to determine a new cross-section on which the noise reduction is to be performed according to the acquisition program.

10. The image processing apparatus of claim 1, wherein the processing circuitry is further configured to calculate an energy for each of the plurality of cross-sections, and select the particular cross-section, of the plurality of cross-sections, having a lowest calculated energy.

11. An X-ray diagnosis apparatus, comprising:

processing circuitry configured to

generate medical image data;

identify a group of pixels corresponding to a blood vessel as an object of interest in medical image data;

determine pixels defining a particular cross-section projected correspondingly to a running direction of the blood vessel and selected from among a plurality of cross-sections having different directions, based on the group of pixels being projected onto each of the plurality of cross-sections having the different directions; and

perform noise reduction on the determined pixels defining the particular cross-section to obtain the determined pixels defining the particular cross-section with less noise.