X-ray image diagnosis apparatus and X-ray image processing method

1. An X-ray image diagnosis apparatus comprising:

an imaging unit that includes an X-ray generation unit for irradiating X-ray onto a subject and an X-ray detection unit for detecting X-ray transmitted through the subject, which are supported so as to be opposed to each other and rotatable about the body axis of the subject placed on a bed;

a control unit that rotates, after injection of contrast medium into the subject, the imaging unit about the body axis of the subject to perform imaging for obtaining images within a predetermined angular range required for image reconstruction, the control unit rotating the imaging unit within a first angular range to perform a first imaging operation and then rotating the imaging unit within a second angular range to perform a second imaging operation, and performs overlapped dense imaging for a phase in which blood containing the contrast medium flows in capillaries as an area to be reconstructed, and performs sparse imaging for a phase in which blood containing the contrast medium flows from the artery to capillaries and from the capillaries to a vein; and

an image data processing unit that performs image reconstruction processing based on two images obtained through the first and second dense imaging operations after compensating a displacement occurring between the images obtained by the first and second imaging operations.

2. The X-ray image diagnosis apparatus according to claim 1 , wherein,

the image data processing unit uses the images obtained through the sparse imaging to compensate a displacement occurring between the images obtained by the two imaging operations.

3. The X-ray image diagnosis apparatus according to claim 1 , wherein,

in the first and second imaging operations, the control unit sets the rotation start time of the imaging unit and time that elapses before the start of imaging based on the time length from the injection of the contrast medium to the time at which blood containing the contrast medium reaches the capillaries.

4. An X-ray image diagnosis apparatus comprising:

an imaging unit that includes an X-ray generation unit for irradiating X-ray onto a subject and an X-ray detection unit for detecting X-ray transmitted through the subject, which are supported so as to be opposed to each other and rotatable about the body axis of the subject placed on a bed;

a control unit that rotates, after injection of contrast medium into the subject, the imaging unit about the body axis of the subject to perform imaging for obtaining images within a predetermined angular range required for image reconstruction, the control unit rotating the imaging unit within a first angular range to perform a first imaging operation and then rotating the imaging unit within a second angular range to perform a second imaging operation, and performs overlapped dense imaging for a phase in which blood containing the contrast medium flows in capillaries as an area to be reconstructed, and performs sparse imaging for a phase in which blood containing the contrast medium flows from the artery to capillaries and from the capillaries to a vein;

a timing setting unit that analyzes the time length from the injection of the contrast medium to the time at which blood containing the contrast medium reaches the capillaries based on the result of the first imaging operation and sets the X-ray irradiation start time in the second imaging operation based on the analysis result; and

an image data processing unit that performs image reconstruction processing based on two images obtained through the first and second dense imaging operations.

5. An X-ray image processing method comprising:

providing an imaging unit that includes an X-ray generation unit for irradiating X-ray onto a subject and an X-ray detection unit for detecting X-ray transmitted through the subject, which are supported so as to be opposed to each other and rotatable about the body axis of the subject placed on a bed;

rotating the imaging unit within a first angular range after injection of contrast medium into the subject to perform a first imaging operation at imaging time in which the imaging unit is rotated about the body axis of the subject to perform imaging for obtaining images within a predetermined angular range required for image reconstruction, and performs sparse imaging for a phase in which blood containing the contrast medium flows from the artery to capillaries and performs dense imaging for a phase in which blood containing the contrast medium flows in capillaries as an area to be reconstructed;

rotating the imaging unit within a second angular range after injection of contrast medium into the subject to perform a second imaging operation such that a part of the first angular range and a part of the second angular range are overlapped with each other, and performs dense imaging for a phase in which blood containing the contrast medium flows in capillaries as an area to be reconstructed and performs sparse imaging for a phase in which blood containing the contrast medium flows from the capillaries to a vein; and

performing image reconstruction processing based on two images obtained through the first and second dense imaging operations after compensating a displacement occurring between the images obtained by the first and second sparse imaging operations.

6. An X-ray image processing method comprising:

providing an imaging unit that includes an X-ray generation unit for irradiating X-ray onto a subject and an X-ray detection unit for detecting X-ray transmitted through the subject, which are supported so as to be opposed to each other and rotatable about the body axis of the subject placed on a bed;

rotating the imaging unit within a first angular range after injection of contrast medium into the subject to perform a first imaging operation at imaging time in which the imaging unit is rotated about the body axis of the subject to perform imaging for obtaining images within a predetermined angular range required for image reconstruction, and performs sparse imaging for a phase in which blood containing the contrast medium flows from the artery to capillaries and performs dense imaging for a phase in which blood containing the contrast medium flows in capillaries as an area to be reconstructed;

analyzing the time length from the injection of the contrast medium to the time at which blood containing the contrast medium reaches the capillaries based on the result of the first imaging operation;

setting the X-ray irradiation start time in the second imaging operation based on the analysis result;

rotating the imaging unit within a second angular range after injection of contrast medium into the subject to perform a second imaging operation such that a part of the first angular range and a part of the second angular range are overlapped with each other, and performs dense imaging for a phase in which blood containing the contrast medium flows in capillaries as an area to be reconstructed and performs sparse imaging for a phase in which blood containing the contrast medium flows from the capillaries to a vein; and

performing image reconstruction processing based on two images obtained through the first and second dense imaging operations.