X-ray diagnosis apparatus

1. An X-ray diagnosis apparatus comprising processing circuitry configured:

to acquire a first X-ray image on a basis of X-rays radiated onto a subject in a first radiation dose;

to acquire a second X-ray image on a basis of X-rays radiated onto the subject in a second radiation dose lower than the first radiation dose;

to acquire a third X-ray image on a basis of X-rays radiated onto a region of interest of the subject into which a medical device is inserted and onto a region other than the region of interest, in mutually-different radiation doses;

to obtain position information of the region of interest in the third X-ray image;

to obtain positions corresponding to the region of interest in the first X-ray image and in the second X-ray image on a basis of the position information; and

to generate a subtraction image by calculating a difference between the region of interest in the third X-ray image and a region corresponding to the region of interest in the first X-ray image and calculating a difference between a region other than the region of interest in the third X-ray image and a region corresponding to the region other than the region of interest in the second X-ray image.

2. The X-ray diagnosis apparatus according to claim 1 , wherein the processing circuitry is configured to obtain the position information from an X-ray image acquired on a basis of X-rays radiated onto the region of interest and the region other than the region of interest, in mutually-different radiation doses.

3. The X-ray diagnosis apparatus according to claim 2 , wherein the processing circuitry is configured to obtain the position information from the third X-ray image.

4. The X-ray diagnosis apparatus according to claim 1 , wherein the processing circuitry is configured to obtain the position information on a basis of a distribution of X-ray radiation doses for the subject.

5. The X-ray diagnosis apparatus according to claim 1 , further comprising a filter that is configured to attenuate X-rays, has a first region to attenuate X-rays passing therethrough as well as one selected from between an opening to pass X-rays without attenuating the X-rays and a second region to attenuate passing X-rays at an attenuation rate lower than an attenuation rate of the X-rays passing through the first region, and is capable of moving the one selected from between the opening and the second region, wherein the processing circuitry is further configured:

to control the moving of the one selected from between the opening and the second region, and

to acquire the third X-ray image on a basis of X-rays emitted from an X-ray tube and subsequently radiated onto the region of interest via the one selected from between the opening and the second region and X-rays emitted from the X-ray tube and subsequently radiated onto the region other than the region of interest via the first region.

6. The X-ray diagnosis apparatus according to claim 5 , wherein the processing circuitry is configured to obtain the position information on a basis of a position of the one selected from between the opening and the second region of the filter.

7. The X-ray diagnosis apparatus according to claim 1 , wherein the processing circuitry is further configured:

to acquire a blood vessel image by calculating a difference between an X-ray image based on X-rays that have passed through the subject before a contrast agent is injected and an X-ray image based on X-rays that have passed through the subject after the contrast agent is injected,

to generate a superimposed image by superimposing the subtraction image and the blood vessel image on each other, and

to cause the superimposed image to be displayed on display.

8. The X-ray diagnosis apparatus according to claim 1 , wherein the processing circuitry is further configured:

to acquire a blood vessel image by calculating a difference between an X-ray image based on X-rays that have passed through the subject before a contrast agent is injected and an X-ray image based on X-rays that have passed through the subject after the contrast agent is injected,

to generate a superimposed image by superimposing an X-ray image based on X-rays that have passed through the subject, the subtraction image, and the blood vessel image on one another, and

to cause the superimposed image to be displayed on display.

9. The X-ray diagnosis apparatus according to claim 7 , wherein the processing circuitry is configured:

to acquire a blood vessel image by calculating a difference between a fluoroscopic image based on X-rays that have passed through the subject before a contrast agent is injected and a fluoroscopic image based on X-rays that have passed through the subject after the contrast agent is injected, and

to generate the subtraction image by using the fluoroscopic image based on the X-rays that have passed through the subject before the contrast agent is injected as the first X-ray image.

10. The X-ray diagnosis apparatus according to claim 1 , wherein the processing circuitry is configured to acquire the third X-ray image on a basis of X-rays radiated onto the region of interest of the subject into which the medical device is inserted in the first radiation dose and radiated onto the region other than the region of interest in the second radiation dose.

11. An X-ray diagnosis apparatus comprising processing circuitry configured:

to acquire a first X-ray image based on X-rays radiated onto a subject;

to generate a second X-ray image and a third X-ray image from the first X-ray image;

to acquire a fourth X-ray image on a basis of X-rays radiated onto a region of interest of the subject into which a medical device is inserted and onto a region other than the region of interest, in mutually-different radiation doses; and

to obtain position information of the region of interest in the fourth X-ray image, wherein the processing circuitry is configured:

to generate, on a basis of the position information, the second X-ray image in correspondence with a brightness level of the region of interest in the fourth X-ray image and the third X-ray image in correspondence with a brightness level of the region other than the region of interest in the fourth X-ray image, and

to generate a subtraction image by calculating a difference between the region of interest in the fourth X-ray image and a region corresponding to the region of interest in the second X-ray image and calculating a difference between the region other than the region of interest in the fourth X-ray image and a region corresponding to the region other than the region of interest in the third X-ray image.

12. The X-ray diagnosis apparatus according to claim 11 , wherein the processing circuitry is configured to obtain the position information from an X-ray image acquired on a basis of X-rays radiated onto the region of interest and the region other than the region of interest, in mutually-different radiation doses.

13. The X-ray diagnosis apparatus according to claim 12 , wherein the processing circuitry is configured to obtain the position information from the fourth X-ray image.

14. The X-ray diagnosis apparatus according to claim 11 , wherein the processing circuitry is configured to obtain the position information on a basis of a distribution of X-ray radiation doses for the subject.

15. The X-ray diagnosis apparatus according to claim 11 , further comprising a filter that is configured to attenuate X-rays, has a first region to attenuate X-rays passing therethrough as well as one selected from between an opening to pass X-rays without attenuating the X-rays and a second region to attenuate passing X-rays at an attenuation rate loner than an attenuation rate of the X-rays passing through the first region, and is capable of moving the one selected from between the opening and the second region, wherein the processing circuitry is further configured:

to control the moving of the one selected from between the opening and the second region,

to acquire the fourth X-ray image on a basis rays emitted from an X-ray tube and subsequently radiated onto the region of interest via the one selected from between the opening and the second region and X-rays emitted from the X-ray tube and subsequently radiated onto the region other than the region of interest via the first region, and

to obtain the position information on a basis of a position of the one selected from between the opening and the second region of the filter.

16. An X-ray diagnosis apparatus comprising processing circuitry configured:

to acquire a first X-ray image based on X-rays radiated onto a subject;

to generate a second X-ray image from the first X-ray image;

to acquire a third X-ray image on a basis of X-rays radiated onto a region of interest of the subject into which a medical device is inserted and onto a region other than the region of interest, in mutually-different radiation doses; and

to obtain position information of the region of interest in the third X-ray image, wherein the processing circuitry is configured:

to generate, on a basis of the position information, the second X-ray image by adjusting a brightness level of a region corresponding to the region of interest in the first X-ray image in correspondence with a brightness level of the region of interest in the third X-ray image and adjusting a brightness level of a region corresponding to the region other than the region of interest in the first X-ray image in correspondence with a brightness level of the region other than the region of interest in the third X-ray image, and

to generate a subtraction image by calculating a difference between the second X-ray image and the third X-ray image.

17. The X-ray diagnosis apparatus according to claim 16 , wherein the processing circuitry is configured to obtain the position information from an X-ray image acquired on a basis of X-rays radiated onto the region of interest and the region other than the region of interest, in mutually-different radiation doses.

18. The X-ray diagnosis apparatus according to claim 17 , wherein the processing circuitry is configured to obtain the position information from the third X-ray image.

19. The X-ray diagnosis apparatus according to claim 16 , wherein the processing circuitry is configured to obtain the position information on a basis of a distribution of X-ray radiation doses for the subject.

20. The X-ray diagnosis apparatus according to claim 16 , further comprising a filter that is configured to attenuate X-rays, has a first region to attenuate X-rays passing therethrough as well as one selected from between an opening to pass X-rays without attenuating the X-rays and a second region to attenuate passing X-rays at an attenuation rate lower than an attenuation rate of the X-rays passing through the first region, and is capable of moving the one selected from between the opening and the second region, wherein the processing circuitry is further configured:

to control the moving of the one selected from between the opening and the second region,

to acquire the third X-ray image on a basis of X-rays emitted from an X-ray tube and subsequently radiated onto the region of interest via the one selected from between the opening and the second region and X-rays emitted from the X-ray tube and subsequently radiated onto the region other than the region of interest via the first region, and

to obtain the position information on a basis of a position of the one selected from between the opening and the second region of the filter.