X-ray diagnosis apparatus

1. An X-ray diagnosis apparatus comprising:

an imaging unit configured to comprise an X-ray tube and a detector to obtain a first X-ray image and a second X-ray image associated with a subject in which a medical tool is inserted;

a first specifying unit configured to specify a first reference point on a first medical tool area included in the first X-ray image;

a designation unit configured to designate a first objective point on the first X-ray image;

a first calculation unit configured to calculate a relative positional relationship between the first reference point and the first objective point;

a second specifying unit configured to specify a second reference point on a second medical tool area included in the second X-ray image;

a second calculation unit configured to calculate a position of a second objective point on the second X-ray image based on the relative positional relationship and the second reference point; and

a display unit configured to display the second X-ray image while highlighting the position of the second objective point.

2. The apparatus according to claim 1 , wherein the designation unit configured to designate the first objected point on the first X-ray image in accordance with one of an instruction from a user and image processing.

3. The apparatus according to claim 1 , wherein

the first specifying unit configured to specify the first reference point included in the first X-ray image by image processing, and

the second specifying unit configured to specify the second reference point included in the second X-ray image by image processing.

4. The apparatus according to claim 1 , wherein the display unit configured to display a mark at the position of the second objective point on the second X-ray image.

5. The apparatus according to claim 1 , wherein

the first X-ray image is an X-ray image depicting one of a treatment region of a blood vessel which is contrast-enhanced by a contrast medium, a branch point of a blood vessel which is contrast-enhanced by a contrast medium, or a mark for a bioabsorbable stent, and

the second X-ray image is an X-ray image which depicts none of the treatment region, the branch point, or the mark.

6. The apparatus according to claim 1 , further comprising a storage unit which stores the relative position information.

7. An X-ray diagnosis apparatus comprising:

a storage unit configured to store a plurality of vectors and a plurality of past electrocardiographic phases in association with each other, each of the plurality of vectors being a vector from a past reference point to a past objective point included in each of a plurality of past images associated with a subject, and each of the plurality of past electrocardiographic phases being an electrocardiographic phase of the subject which is associated with a time at which the past image was obtained;

an imaging unit configured to comprise an X-ray tube and a detector to obtain a current image associated with the subject;

a first specifying unit configured to specify a current reference point on the current image by image processing;

a detection unit configured to detect a current electrocardiographic phase associated with the current image;

a second specifying unit configured to specify a specific vector associated with a past electrocardiographic phase corresponding to the detected current electrocardiographic phase among the plurality of vectors;

a first calculation unit configured to calculate a position of a current objective point on the current image based on the specified vector and the position of the current reference point; and

a display unit configured to display the position of the current objective point on the current image.

8. The apparatus according to claim 7 , further comprising a third specifying unit configured to specify the past reference point by processing each of the plurality of past images.

9. The apparatus according to claim 7 , further comprising a designation unit configured to designate the past objective point in accordance with one of processing each of the plurality of past images and an instruction from a user.

10. The apparatus according to claim 7 , further comprising a second calculation unit configured to calculate the vector from the past reference point to the past objective point for each of the plurality of past images.

11. The apparatus according to claim 7 , further comprising an interpolation unit configured to interpolate a vector associated with an electrocardiographic phase between the two past electrocardiographic phases based on two vectors of the plurality of vectors, the two vectors are associated with two temporally adjacent past electrocardiographic phases.

12. The apparatus according to claim 7 , wherein the storage unit configured to store only a predetermined past electrocardiographic phase of the plurality of past electrocardiographic phases and a vector associated with the predetermined past electrocardiographic phase.

13. The apparatus according to claim 7 , wherein the display unit configured to display a mark at the position of the current objective point.

14. The apparatus according to claim 7 , wherein

the past image is an X-ray image depicting one of a treatment region of a blood vessel which is contrast-enhanced by a contrast medium, a branch point of a blood vessel which is contrast-enhanced by a contrast medium, or a mark for a bioabsorbable stent, and

the current image is an X-ray image which depicts none of the treatment region, the branch point, or the mark.