Medical image diagnostic apparatus

1. A medical image diagnostic apparatus, comprising:

an X-ray tube configured to irradiate an object with X-rays;

an X-ray detector configured to detect the X-rays;

processing circuitry configured to generate an X-ray image based on the detected X-rays; and

a display configured to display an incident dose region, which illustrates an incident dose distribution of the X-rays on the object, superimposed on an object image indicating the object,

wherein the processing circuitry is further configured to correct, based on the generated X-ray image, a relative positional relationship between the object image and the incident dose region that is superimposed on the object image.

2. The apparatus according to claim 1 , wherein the processing circuitry is further configured to correct at least one of a position and a size of the object image based on an anatomical landmark in the X-ray image.

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

generate a different direction image corresponding to an imaging direction different from in imaging direction of the X-ray image, and

correct at least one of a size of the incident dose region and a size of the object image based on an anatomical landmark in the different direction image.

4. The apparatus according to claim 1 , wherein the processing circuitry is further configured to:

detect a positional shift between an irradiation range of the X-rays and the incident dose region, and

calculate the incident dose distribution based on an X-ray generation condition concerning generation of the X-rays, the irradiation range of the X-rays, the corrected positional relationship, and a position of the X-ray tube with respect to a patient table, in response to detection of the positional shift.

5. The apparatus according to claim 4 , further comprising input circuitry configured to input a predetermined time interval concerning recalculation of the incident dose distribution,

wherein the processing circuitry is further configured to recalculate the incident dose distribution during a period defined from a previous time that is prior to a detection time of the positional shift by the time interval, to the detection time.

6. The apparatus according to claim 1 , wherein the object image is a three-dimensional object model schematically indicating the object and having an anatomical landmark, and

the processing circuitry is further configured to correct at least one of a position and a size of the object image based on an anatomical landmark in the X-ray image and an anatomical landmark in the object model.

7. The apparatus according to claim 6 , wherein the processing circuitry is further configured to

detect a positional shift between an anatomical landmark of a predetermined organ in the X-ray image and an anatomical landmark of the predetermined organ in the object model, and

calculate the incident dose distribution based on the positional relationship corrected based on the positional shift, an irradiation range of the X-ray, an X-ray generation condition concerning generation of the X-rays, and a position of the X-ray tube with respect to a patient table, in response to detection of the positional shift.

8. The apparatus of claim 7 , wherein the processing circuitry is further configured to correct at least one of a position and a size of the object model by rotating the object model based on the positional shift.

9. The apparatus according to claim 1 , further comprising:

a memory storing a plurality of three-dimensional object models schematically indicating the object, wherein the processing circuitry is further configured to

specify, as the object image, an object model matching a size of the object, from the object models, based on the X-ray image and the object image; and

recalculate the incident dose distribution at a past time prior to a current time in an X-ray examination on the object based on the specified object model, an irradiation range of the X-ray, an X-ray generation condition concerning generation of the X-rays, the corrected positional relationship, and a position of the X-ray tube with respect to a patient table, in response to specifying of the object model.

10. The apparatus according to claim 9 , wherein the size of the object corresponds to an outer shape of the object.

11. The apparatus according to claim 1 , further comprising:

a memory storing a plurality of three-dimensional object models schematically indicating an object; and

input circuitry configured to input a change of the object model,

wherein the processing circuitry is further configured to recalculate the incident dose distribution at a past time prior to a current time in an X-ray examination on the object based on the changed object model, an irradiation range of the X-ray, an X-ray generation condition concerning generation of the X-rays, the corrected positional relationship, and a position of the X-ray tube with respect to a patient table, in response to a change of the object model.

12. The apparatus according to claim 1 , further comprising:

a memory storing a plurality of three-dimensional object models schematically indicating the object and past volume data corresponding to each of a plurality of patients;

input circuitry configured to input a change instruction for past volume data concerning the object in the past volume data, wherein the processing circuitry is further configured to

specify, as the object image, an object model matching an outer shape of the object, from the object models, based on volume data corresponding to the change instruction and the object image, and

recalculate the incident dose distribution of a past time prior to a current time in an X-ray examination on the object based on the specified object model, an irradiation range of the X-ray, an X-ray generation condition concerning generation of the X-rays, the corrected positional relationship, and a position of the X-ray tube with respect to a patient table.

13. The apparatus according to claim 1 , wherein the processing circuitry is further configured to generate volume data based on a plurality of X-ray images acquired by rotating the X-ray tube and the X-ray detector around the object while making the X-ray tube and the X-ray detector face each other, and

the apparatus further comprises

a memory storing a plurality of three-dimensional object models schematically indicating the object as the object image, wherein the processing circuitry is further configured to

specify, as the object image, an object model matching an outer shape of the object from the object models, based on the volume data and the object image, and

recalculate the incident dose distribution at a past time prior to a current time in an X-ray examination on the object based on the specified object model, an irradiation range of the X-ray, an X-ray generation condition concerning generation of X-rays, the corrected positional relationship, and a position of the X-ray tube with respect to the patient table, in response to specifying of the object model.

14. The apparatus according to claim 1 , wherein the processing circuitry is further configured to generate, as the object image, a three-dimensional measurement image having measurement data concerning the object, based on volume data of the object,

the display is configured to display the measurement image in place of the object image, in response to generation of the measurement image, and

the processing circuitry is further configured to correct a relative positional relationship between the measurement image and the incident region dose on the measurement image based on the volume data.

15. The apparatus according to claim 14 , wherein the processing circuitry is further configured to recalculate the incident dose distribution at a past time prior to a current time in an X-ray examination on the object based on an X-ray generation condition concerning generation of the X-rays, an irradiation range of the X-ray, the measurement image, the corrected positional relationship, and a position of the X-ray tube with respect to a patient table, in response to generation of the measurement image.

16. The apparatus according to claim 15 , wherein when the measurement image is an image indicating a portion of the object, the processing circuitry is configured to generate, as the object image, a combined image obtained by combining a three-dimensional object model indicating a portion different from the portion indicated with the measurement image, and

the display is configured to display the combined image in place of the object image, in response to generation of the combined image.

17. The apparatus according to claim 15 , wherein the volume data comprises at least one of

data reconstructed by X-ray computed tomography or magnetic resonance imaging with respect to the object, and

data reconstructed based on a plurality of X-ray images acquired by rotating, around the object, a support frame which supports the X-ray tube and the X-ray detector so as to make the X-ray tube and the X-ray detector face each other.

18. The apparatus according to claim 1 , wherein the X-ray image comprises real-time fluoroscopic images sequentially generated by the processing circuitry.

19. The apparatus according to claim 1 , wherein the incident dose distribution comprises an entrance skin dose distribution on the object.

20. A medical image diagnostic apparatus, comprising:

a memory storing an X-ray generation condition concerning generation of X-rays irradiated to an object, an irradiation range of the X-rays concerning the object, a position of an X-ray tube with respect to a patient table, a relative positional relationship between an object image indicating the object and an incident dose region illustrating an incident dose distribution superimposed on the object image, and volume data acquired after an X-ray examination on the object;

processing circuitry configured to

correct the positional relationship by using the volume data;

recalculate the incident dose distribution over a period during which the X-ray image is executed, based on the X-ray generation condition, the irradiation range, the corrected positional relationship, and the position of the X-ray tube; and

a display configured to superimpose the recalculated incident dose distribution on the object image by using the corrected positional relationship over the period, and display the image as a moving image.