阅读说明：本技术 放射线透视摄影装置 (Radiographic apparatus ) 是由 D·蒂博·佩尔蒂埃 长谷川直纪 丹野圭一 山本贵也 于 2020-03-03 设计创作，主要内容包括：本发明提供一种放射线透视摄影装置。在该放射线透视摄影装置中,图像处理部构成为：在拍摄多个造影剂图像时,进行使作为摄影对象的血管清晰化的第一图像处理来生成第一图像,并且通过进行第二图像处理来生成用于生成差分全景图像的多个第二图像。(The invention provides a radiographic apparatus. In the radiographic apparatus, the image processing unit is configured to: when a plurality of contrast agent images are captured, first image processing for sharpening a blood vessel as an imaging target is performed to generate a first image, and second image processing is performed to generate a plurality of second images for generating a differential panoramic image.)

1. A radiographic apparatus includes:

an imaging unit including a radiation source that irradiates a subject with radiation, and a detection unit that detects radiation irradiated from the radiation source and transmitted through the subject to acquire a detection signal;

an image processing unit that generates a plurality of contrast agent images based on the detection signals acquired at a plurality of relative positions using a contrast agent, generates a plurality of non-contrast agent images based on the detection signals acquired at the plurality of relative positions without using a contrast agent, and generates a differential panoramic image by subtracting and joining the contrast agent images and the non-contrast agent images; and

a control unit that performs control of outputting the image generated by the image processing unit and causing a display unit to display the image,

wherein the image processing unit is configured to: generating a first image by performing first image processing for sharpening blood vessels as an imaging target on the plurality of contrast medium images when the plurality of contrast medium images are imaged while changing the relative position of the imaging unit and the subject, and generating a plurality of second images for generating the difference panoramic image by performing second image processing for reducing a difference in pixel value between the contrast medium image and the non-contrast medium image in a portion of the subject common to the plurality of contrast medium images,

the control unit is configured to: when the plurality of contrast agent images are captured while changing the relative position of the imaging unit and the subject, control is performed to sequentially display the first images corresponding to the respective contrast agent images.

2. The radiographic apparatus according to claim 1,

the image processing unit is configured to: generating a plurality of third images for generating the differential panoramic image by subjecting the plurality of non-contrast agent images to third image processing that reduces a difference in pixel value of a portion of the subject that is common in the contrast agent image and the non-contrast agent image, and generating the differential panoramic image from the plurality of second images and the plurality of third images.

3. The radiographic apparatus according to claim 2,

the imaging conditions such as the radiation dose, the imaging start position, and the imaging timing are the same between the contrast medium image and the non-contrast medium image,

the image processing unit is configured to: the contrast agent image is subjected to gradation processing as the second image processing, and the non-contrast agent image is subjected to gradation processing as the third image processing.

4. The radiographic apparatus according to claim 2,

the control unit is configured to: when the non-contrast agent image is captured while changing the relative position of the imaging unit and the subject, the display unit sequentially displays a difference image obtained by subtracting the second image and the third image corresponding to the respective non-contrast agent images.

5. The radiographic apparatus according to claim 2,

the image processing unit is configured to: fourth image processing for generating an image representing the contour of a portion other than the blood vessel is performed.

6. The radiographic apparatus according to claim 5,

the image processing unit is configured to: the same first processing is performed as the first image processing and the fourth image processing, and the same second processing is performed as the second image processing and the third image processing.

7. The radiographic apparatus according to claim 6,

the image processing section includes: a first processing unit that performs the first processing on the contrast agent image and the non-contrast agent image; and a second processing unit that performs the second processing on the contrast agent image and the non-contrast agent image.

8. The radiographic apparatus according to claim 1,

the image processing unit is configured to: as the first image processing, a defocused image that makes the blood vessels unclear and makes the portions other than the blood vessels clearer is generated from the contrast agent image, and the first image that makes the blood vessels clearer is generated by subtracting the defocused image and the contrast agent image.

Technical Field

The present invention relates to a radioscopy apparatus, and more particularly, to a radioscopy apparatus that generates a differential panoramic image.

Background

Conventionally, an X-ray diagnostic apparatus that generates a differential panoramic image by irradiating an object with X-rays is known. Such a radiographic apparatus is disclosed in, for example, japanese patent application laid-open No. 2010-162278.

The X-ray image diagnostic apparatus disclosed in japanese patent application laid-open No. 2010-162278 acquires an X-ray image group by moving a detector relative to a subject and performing X-ray imaging, and generates a panoramic image by superimposing a part of the acquired X-ray image group. In addition, the X-ray image diagnostic apparatus of japanese patent application laid-open No. 2010-162278 includes a DSA (digital subtraction angiography) imaging mode in which a difference image (DSA image) as a blood vessel image is generated by subtracting an X-ray transmission image (mask image) of an image not including a contrast agent and an X-ray transmission image (contrast image or real-time image) of an image including a contrast agent, and the DSA image is displayed/stored. The X-ray image diagnostic apparatus described in japanese patent application laid-open No. 2010-162278 collects a mask image and then collects a real-time image. The X-ray image diagnostic apparatus disclosed in japanese patent application laid-open No. 2010-162278 generates a panoramic image based on the acquired DSA image.

Disclosure of Invention

Although not disclosed in the above-mentioned japanese patent application laid-open No. 2010-162278, conventionally, in order to clearly image a blood vessel, a contrast medium image (live image) is taken in a state where a contrast medium is sufficiently contained in the blood vessel at an imaging position. Therefore, it is necessary to relatively move the detector and the object to capture a contrast agent image in accordance with the timing of the contrast agent movement.

However, the X-ray image diagnostic apparatus as described in japanese patent application laid-open No. 2010-162278 has a problem that a desired differential panoramic image cannot be appropriately generated. That is, in the X-ray image diagnostic apparatus of patent document 1, after a contrast medium image (live image) and a non-contrast medium image (mask image) are captured, subtraction processing (subtraction processing) is performed to acquire a differential image which is a blood vessel image in which blood vessels are clarified. Therefore, a difference image is not generated when a contrast medium image is imaged. Therefore, when imaging a contrast medium image, it is confirmed whether or not a contrast medium is sufficiently contained in a blood vessel based on an acquired contrast medium image, not based on a differential image, and there is a problem in that: since the contrast medium image includes a portion other than the blood vessel, visibility is poor, and the movement of the contrast medium cannot be clearly confirmed. When the movement of the contrast agent cannot be clearly confirmed, the detector and the subject cannot be moved relative to each other in accordance with the timing of the movement of the contrast agent, and an appropriate contrast agent image for generating the differential panoramic image may not be acquired.

On the other hand, the following problem is also caused when the non-contrast agent image is imaged. That is, in the X-ray image diagnostic apparatus of patent document 1, since the non-contrast agent image is captured and then the contrast agent image is captured, the blood vessel cannot be confirmed when the non-contrast agent image is captured. Therefore, for example, when the object is placed at a position that is not expected from the relative positional relationship between the detector and the object, the non-contrast agent image is imaged without noticing this. As a result, there are the following problems: re-imaging is required, resulting in an increase in the amount of radiation to be irradiated to the subject.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a radioscopic imaging apparatus capable of appropriately generating a desired differential panoramic image.

In order to achieve the above object, a radioscopy apparatus according to one aspect of the present invention includes: an imaging unit including a radiation source that irradiates a subject with radiation, and a detection unit that detects radiation irradiated from the radiation source and transmitted through the subject to acquire a detection signal; an image processing unit that generates a plurality of contrast agent images based on detection signals acquired at a plurality of relative positions using a contrast agent, generates a plurality of non-contrast agent images based on detection signals acquired at a plurality of relative positions without using a contrast agent, and generates a differential panoramic image by subtracting and joining the contrast agent images and the non-contrast agent images; and a control unit that performs control of outputting the image generated by the image processing unit and causing the display unit to display the image, wherein the image processing unit is configured to: the control unit generates a plurality of second images for generating a differential panoramic image by performing first image processing for sharpening a blood vessel to be imaged on a plurality of contrast agent images to generate a first image and performing second image processing for reducing a difference in pixel value between a portion of a subject common to the contrast agent images and a non-contrast agent image, and is configured to: when a plurality of contrast agent images are captured while changing the relative position of the imaging unit and the subject, control is performed to sequentially display first images corresponding to the respective contrast agent images.

According to the radioscopy apparatus of the present invention, the image processing unit is configured to perform first image processing for sharpening a blood vessel to be imaged with respect to a plurality of contrast agent images to generate a first image, and the control unit is configured to perform the following control when imaging the plurality of contrast agent images while changing the relative position of the imaging unit and the subject: first images corresponding to the respective contrast agent images are sequentially displayed, and a plurality of second images for generating a differential panoramic image are generated by performing second image processing that reduces a difference in pixel value of a portion of the subject that is common in the contrast agent image and the non-contrast agent image. Thus, when a plurality of contrast medium images are captured while changing the relative position of the imaging unit and the subject, the first image for clarifying the blood vessel as the imaging target corresponding to each contrast medium image is generated and displayed, and therefore, the user can clearly confirm the movement of the contrast medium in the blood vessel when imaging the contrast medium image. Further, by generating a plurality of second images for generating a difference panoramic image, a difference image can be generated when a non-contrast agent image is captured, and thus blood vessels can be confirmed when a non-contrast agent image is captured. As a result, a radioscopy apparatus capable of appropriately generating a desired difference panoramic image can be provided.

Drawings

Fig. 1 is a block diagram showing a configuration of an X-ray fluoroscopic apparatus.

Fig. 2 is a diagram showing an example of an X-ray fluoroscopic apparatus.

Fig. 3 is a diagram for explaining a flow of generation of a differential panoramic image by the image processing unit.

Fig. 4 is a diagram for explaining generation of a defocused image.

Fig. 5 is a diagram for explaining generation of the first image.

Fig. 6 is a diagram for explaining generation of the second image.

Fig. 7 is a diagram for explaining generation of a third image.

Fig. 8 is a diagram for explaining generation of a DSA image.

Fig. 9 is a diagram for explaining the fourth image.

Fig. 10 is a diagram showing a differential panoramic image.

Fig. 11 is a flowchart for explaining generation of a contrast agent image.

Fig. 12 is a flowchart for explaining generation of a differential panoramic image.

Detailed Description

Hereinafter, embodiments embodying the present invention will be described based on the drawings.

[ present embodiment ]

The configuration of an X-ray fluoroscopic imaging apparatus 100 according to the present embodiment will be described with reference to fig. 1 to 10. The X-ray fluoroscopic apparatus 100 is an example of the "radiographic apparatus" of the present invention.

(Structure of X-ray fluoroscopic apparatus)

As shown in fig. 1, the X-ray fluoroscopic imaging apparatus 100 of the present embodiment includes an imaging unit 10, an image processing unit 3, and a control unit 4, and the imaging unit 10 includes an X-ray source 1 and a detection unit 2.

As shown in fig. 2, the X-ray fluoroscopic apparatus 100 of the present embodiment is configured to irradiate X-rays from the X-ray source 1 to the subject 50 mounted on the top 5.

The top plate 5 is formed in a flat plate shape having a rectangular shape in a plan view. The subject 50 is placed on the top panel 5 such that the head-foot direction of the subject 50 is a direction along the long side of the rectangle, and the left-right direction of the subject 50 is a direction along the short side of the rectangle. In the present specification, the head-foot direction of the subject 50 is defined as the X direction, the left-right direction of the subject 50 is defined as the Z direction, and a direction orthogonal to the X direction and the Z direction is defined as the Y direction.

The X-ray source 1 is disposed on one side of the top plate 5 in the Y direction. The X-ray source 1 can emit X-rays by applying a voltage thereto by a driving unit not shown. The X-ray source 1 has a collimator capable of adjusting an irradiation field, which is an irradiation range of X-rays. In the present embodiment, the X-ray source 1 is attached to the tip of one side (Y2 direction side) of the arm 6.

The detector 2 is attached to the tip of the other side (the side opposite to the X-ray source 1) of the arm 6. That is, the detector 2 is disposed on the side opposite to the X-ray source 1 with the top plate 5 interposed therebetween. The detector 2 is configured to be able to detect X-rays. The detection unit 2 is, for example, an FPD (flat panel detector).

As shown in fig. 1, the image Processing Unit 3 is a computer configured to include a processor such as a GPU (Graphics Processing Unit) or a Field-Programmable Gate Array (FPGA) for image Processing. The image processing unit 3 functions as an image processing apparatus by executing an image processing program.

As shown in fig. 1, the image processing section 3 includes a first processing section 31 and a second processing section 32. The first processing unit 31 is configured to perform the first image processing 33 and the fourth image processing 36. The second processing unit 32 is configured to perform the second image processing 34 and the third image processing 35.

As shown in fig. 1, the control Unit 4 is a computer including a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory).

The X-ray fluoroscopic imaging apparatus 100 of the present embodiment includes a display unit 7 and a storage unit 8. In the present embodiment, the display unit 7 is a monitor provided in a examination room or the like for performing X-ray fluoroscopy. The control unit 4 is configured to output the first image 13 and the difference image 17 (see fig. 3) to the display unit 7.

The storage unit 8 is a CPU and a ROM provided in the control unit 4. The storage unit 8 is configured to store the second image 14 generated by the image processing unit 3.

The X-ray fluoroscopic imaging apparatus 100 is used to capture an image for diagnosing the subject 50. In the present embodiment, the target site is a blood vessel 50a of the lower limb of the subject 50.

Since the blood vessels 50a of the lower limbs extend from the root of the thigh to the toe of the subject 50, all the blood vessels cannot be imaged by one imaging. Therefore, the differential panoramic image 18 obtained by joining a plurality of images is used for diagnosis.

As shown in fig. 10, a plurality of differential images 17 obtained by subtracting a plurality of contrast agent images 11 and a plurality of non-contrast agent images 12 having the same relative position coordinates are joined in the order of the relative position coordinates of the top 5 based on the relative position coordinates of the top 5 to generate a differential panoramic image 18.

As shown in fig. 4, the contrast agent image 11 is an image in which a blood vessel 50a is captured. Here, a portion where the attenuation rate of the irradiated X-ray does not change from the surrounding tissue like the blood vessel 50a is not clear on the X-ray image in a state where the contrast medium is not administered. Therefore, by administering a contrast agent that blocks X-rays and changes the attenuation rate of the X-rays, the attenuation rate of the X-rays irradiated to the blood vessel 50a to which the contrast agent is administered changes compared to the surrounding tissue, and thus contrast occurs, and imaging can be performed.

As shown in fig. 7, the non-contrast agent image 12 is an image captured in a state where no contrast agent is administered to the subject 50. Therefore, the blood vessel 50a is unclear as compared to the contrast agent image 11. If the imaging conditions of the non-contrast agent image 12 are made the same as those of the contrast agent image 11, an image can be generated which is the same except for the distinction of whether or not the blood vessel 50a is clear.

As shown in fig. 8, the differential image 17 is an image in which the common portion other than the blood vessel 50a is not clarified and the blood vessel 50a is clarified by subtracting the contrast agent image 11 and the non-contrast agent image 12.

(Generation of differential panoramic image)

The generation of the difference panoramic image 18 by the X-ray fluoroscopic imaging apparatus 100 according to the present embodiment will be described with reference to fig. 3 to 10.

As shown in fig. 3, the image processing unit 3 is configured to generate images including a contrast agent image 11, a non-contrast agent image 12, a first image 13, a second image 14, a third image 15, a fourth image 16, a difference image 17, and a difference panoramic image 18 based on a detection signal from the detection unit 2.

As shown in fig. 2 and 3, the contrast medium image 11 is an image obtained by performing a plurality of imaging operations while changing the relative position of the imaging unit 10 and the subject 50 by moving the imaging unit 10 in the X direction in a state where the contrast medium is administered to the subject 50. In the present embodiment, the configuration is such that: the imaging unit 10 captures a plurality of contrast medium images 11 in a state where the user has administered a contrast medium to a portion of the subject 50 from the base of the thigh to the toe.

The X-ray source 1 is configured to irradiate the subject 50 with X-rays in a state where a contrast medium is administered to the subject 50. The detector 2 is configured to detect X-rays and output a detection signal.

As shown in fig. 1 and 4, the image processing unit 3 is configured to generate a contrast agent image 11 based on the detection signal. The generated contrast medium image 11 is configured such that the contrast medium image 11 is input to the first processing unit 31 and the second processing unit 32 every time the contrast medium image 11 is generated.

As shown in fig. 4, the image processing unit 3 is configured to: the contrast medium image 11 input to the first processing unit 31 is subjected to first image processing 33 for blurring a blood vessel 50a to be imaged, and a defocus image 19 for blurring the blood vessel 50a and blurring a portion other than the blood vessel 50a (e.g., a bone 50b) is generated from the contrast medium image 11. In fig. 4, the case where the blood vessel 50a becomes unclear is indicated by a broken line.

The image processing unit 3 is configured to perform, for example, a process of removing a high-frequency component from the contrast agent image 11 using a low-pass filter as the first image processing 33. This removes the blood vessels 50a, which are high-frequency components, and thus makes them unclear, thereby generating the defocused image 19.

As shown in fig. 5, the image processing unit 3 is configured to generate the first image 13 in which the portion other than the blood vessel 50a is not clear and the blood vessel 50a is cleared by subtracting the contrast medium image 11 and the defocus image 19. By subtracting the contrast agent image 11 and the defocus image 19, the pixel value of a portion (portion other than the blood vessel 50 a) common to the contrast agent image 11 and the defocus image 19 is 0 or close to 0. Therefore, the portion (portion other than the blood vessel 50 a) common to the contrast agent image 11 and the defocus image 19 is unclear by the subtraction.

As shown in fig. 1 and 2, the control unit 4 is configured to perform the following control: when the contrast agent image 11 is captured while the relative position of the imaging unit 10 and the subject 50 is changed, if the first image 13 is generated by the image processing unit 3, the first image 13 is immediately displayed on the display unit 7. The control unit 4 is configured to control the display unit 7 to sequentially display the first image 13 each time the first image 13 is generated.

As shown in fig. 6, the second processing unit 32 of the image processing unit 3 is configured to perform the second image processing 34 for reducing the difference in pixel value between the part of the subject 50 (for example, the bone 50b) shared between the contrast agent image 11 and the non-contrast agent image 12, on the contrast agent image 11. The image processing unit 3 inputs the contrast medium image 11 to the first processing unit 31 and the second processing unit 32 every time the contrast medium image 11 is generated. The image processing unit 3 is configured to perform the first image processing 33 and the second image processing 34 in parallel. The image processing unit 3 is configured to generate the second image 14 for generating the difference panoramic image 18 by performing the second image processing 34.

The image processing unit 3 is configured to perform gradation processing of the contrast medium image 11 as the second image processing 34 based on a parameter set in advance. In fig. 6, hatching is applied to show that the bone 50b is subjected to gradation processing.

The control unit 4 is configured to perform the following control: the storage unit 8 stores a plurality of second images 14 obtained by imaging from the base of the thigh to the toe of the subject 50 while changing the relative position of the subject 50 and the imaging unit 10.

(imaging of non-contrast agent image)

The control unit 4 is configured to: the imaging conditions at the time of imaging the contrast agent image 11 are stored, and the imaging section 10 is controlled so that the non-contrast agent image 12 is imaged based on the stored imaging conditions. The imaging conditions include the radiation dose at the time of imaging, the imaging start position, the imaging timing, the relative positions of the X-ray source 1, the detector 2, and the top 5, and the like. The control unit 4 is configured to control the imaging unit 10 so as to capture the non-contrast medium image 12 under the same imaging conditions such as the radiation dose, the imaging start position, and the imaging timing when the contrast medium image 11 is captured.

The non-contrast agent image 12 is imaged in a state where no contrast agent is administered to the subject 50. The detector 2 is configured to detect the X-rays transmitted through the subject 50 and output a detection signal.

The image processing unit 3 is configured to generate a non-contrast agent image 12 based on the detection signal. Each time the non-contrast agent image 12 is generated, the non-contrast agent image 12 is input to the first processing unit 31 and the second processing unit 32 of the image processing unit 3.

As shown in fig. 7, the second processing unit 32 of the image processing unit 3 is configured to perform third image processing 35 for reducing the difference in pixel value between the part of the subject 50 (e.g., the bone 50b) shared between the contrast medium image 11 and the non-contrast medium image 12, on the non-contrast medium image 12. The image processing unit 3 is configured to generate the third image 15 for generating the difference panoramic image 18 by performing the third image processing 35 on the non-contrast agent image 12.

As the third image processing 35, the image processing unit 3 performs gradation processing of the non-contrast agent image 12 based on the same parameters as those of the second image processing 34, which are set in advance, in the same manner as the second image processing 34. In fig. 7, hatching is applied to show that the bone 50b is subjected to gradation processing.

As shown in fig. 8, the image processing unit 3 generates the third image 15 every time the non-contrast agent image 12 is generated. A difference image 17 is generated based on the generated third image 15 and the second image 14 having the same position coordinates as the generated third image 15. In the differential image 17, the portion (portion other than the blood vessel 50 a) shared by the second image 14 and the third image 15 is removed by subtracting the third image 15 from the second image 14, and thus the blood vessel 50a becomes a sharp image. The difference image 17 is generated every time the third image 15 is generated, and the difference image 17 is sequentially displayed on the display unit 7 every time the difference image 17 is generated.

As shown in fig. 9, the first processing unit 31 of the image processing unit 3 is configured to: fourth image processing 36 is performed to generate a fourth image 16 representing the contour of the portion other than the blood vessel in the non-contrast agent image 12.

The image processing unit 3 is configured to generate an image obtained by performing, for example, a process of removing a high-frequency component from the non-contrast agent image 12 using a low-pass filter as the fourth image processing 36. The image processing unit 3 is configured to generate the fourth image 16 by subtracting the image from which the high-frequency component is removed from the non-contrast agent image 12. Furthermore, the fourth image 16 is relatively unclear compared to the other images and is therefore indicated by a dashed line in fig. 9.

The control unit 4 is configured to control the storage unit 8 to store the fourth image 16. The fourth image 16 is used to confirm the outline of the portion other than the blood vessel 50 a.

As shown in fig. 10, the image processing unit 3 joins the difference images 17 to generate a difference panoramic image 18. The image processing unit 3 is configured to join the difference images 17 in the order of the relative position coordinates of the top 5 based on the relative position coordinates of the top 5 to generate a difference panoramic image 18.

The control unit 4 is configured to: when the non-contrast agent image 12 is captured while changing the relative position between the imaging unit 10 and the subject 50, the display unit 7 performs control to sequentially display a difference image 17 (see fig. 8) obtained by subtracting the second image 14 and the third image 15 generated by the image processing unit 3.

(photography of differential panoramic image)

An imaging operation of the differential panoramic image 18 in which the blood vessel 50a of the lower limb of the subject 50 is an imaging target in the X-ray fluoroscopic imaging apparatus 100 will be described with reference to fig. 11 and 12.

As shown in fig. 11, the X-ray fluoroscopic imaging apparatus 100 is configured to start imaging of the contrast medium image 11 upon receiving an input from a user. The contrast agent image 11 is imaged while a contrast agent is administered to a blood vessel 50a of the lower limb of the subject 50.

In step 81, the X-ray fluoroscopic apparatus 100 is configured to change the relative position between the subject 50 and the imaging unit 10 by moving the top 5.

In step 82, the X-ray source 1 irradiates the subject 50 with X-rays to capture the contrast agent image 11. The detector 2 is configured to detect the X-rays transmitted through the subject 50 and output a detection signal. The image processing unit 3 is configured to generate a contrast medium image 11 based on the detection signal output from the detection unit 2. The generated contrast medium image 11 is output to the first processing unit 31 and the second processing unit 32.

In step 83, the first processing unit 31 is configured to perform the first image processing 33 on the captured contrast agent image 11. The first processing unit 31 is configured to: as the first image processing 33, a low-pass filter is applied to the contrast agent image 11 to generate a defocused image 19. The first processing unit 31 is configured to generate the first image 13 by subtracting the defocused image 19 from the contrast agent image 11.

In step 84, the second processing unit 32 is configured to perform the second image processing 34 simultaneously with the first image processing 33. In this case, the second processing unit 32 is configured to: as the second image processing 34, the contrast agent image 11 is subjected to gradation processing to generate the second image 14. The generated second image 14 is stored in the storage unit 8.

In step 85, the control unit 4 is configured to perform control to output the generated first image 13 to the display unit 7 and to cause the display unit 7 to display the first image 13. This allows the user to perform imaging while checking whether or not the blood vessel 50a of the lower limb contains a sufficient amount of contrast medium.

In step 86, the X-ray fluoroscopic imaging apparatus 100 is configured to: upon receiving an input of the user to end the imaging of the contrast medium image 11, the X-ray fluoroscopic imaging apparatus 100 ends the imaging of the contrast medium image 11. When there is no input from the user, the procedure returns to step 81, and the X-ray fluoroscopic apparatus 100 is configured to change the relative position between the imaging unit 10 and the subject 50 by moving the top 5.

As shown in fig. 12, the X-ray fluoroscopic imaging apparatus 100 is configured to start imaging of the non-contrast medium image 12 upon receiving an input from a user. In the imaging of the non-contrast medium image 12, no contrast medium is administered to the blood vessel 50a of the lower limb of the subject 50.

In step 91, the X-ray fluoroscopic system 100 is configured to change the relative position between the subject 50 and the imaging unit 10 by moving the top 5.

In step 92, the X-ray source 1 irradiates the subject 50 with X-rays to capture the non-contrast agent image 12. The detector 2 is configured to detect the X-rays transmitted through the subject 50 and output a detection signal. The image processing unit 3 is configured to generate the non-contrast agent image 12 based on the detection signal output from the detection unit 2. The generated non-contrast agent image 12 is output to the first processing unit 31 and the second processing unit 32.

The imaging unit 10 is configured to capture the non-contrast agent image 12 under the same imaging conditions as those for the contrast agent image 11. The X-ray fluoroscopic imaging apparatus 100 stores imaging conditions such as the radiation dose, the imaging start position, and the imaging timing of the contrast medium image 11 at the time of imaging in the storage unit 8, and performs imaging of the non-contrast medium image 12 based on the stored imaging conditions.

In step 93, the image processing unit 3 is configured to perform the third image processing 35 on the non-contrast agent image 12. The image processing unit 3 is configured to: as the third image processing 35, gradation processing is performed on the non-contrast agent image 12 so as to reduce the difference in pixel value between the portions of the contrast agent image 11 and the non-contrast agent image 12 in common, as in the second image processing 34.

In step 94, the image processing unit 3 is configured to generate a difference image 17 from the second image 14 and the third image 15 stored in the storage unit 8. The control unit 4 is configured to subtract the second image 14 and the third image 15 captured at the same imaging position as the third image 15 generated by the image processing unit 3 from each other in the second image 14 stored in the storage unit 8. The image processing unit 3 is configured to generate a difference image 17 by subtracting the third image 15 from the second image 14.

In step 95, the control unit 4 controls the display unit 7 to display the difference image 17. This allows the user to photograph the non-contrast agent image 12 while checking the displayed difference image 17.

When the user receives an input to end the imaging of the non-contrast agent image 12 in step 96, the X-ray fluoroscopic apparatus 100 ends the imaging of the non-contrast agent image 12 and moves to step 97. When there is no input from the user, the procedure returns to step 91, and the X-ray fluoroscopic apparatus 100 is configured to change the relative position between the imaging unit 10 and the subject 50 by moving the top 5.

In step 97, the image processing unit 3 is configured to join the difference images 17 in the order of the relative position coordinates of the top 5 based on the relative position coordinates of the top 5 to generate the difference panoramic image 18.

(Effect of the present embodiment)

In the present embodiment, the following effects can be obtained.

In the X-ray fluoroscopic imaging apparatus 100 according to the present embodiment, the image processing unit 3 is configured to perform the first image processing 33 for sharpening the blood vessel 50a as the imaging target on the plurality of contrast agent images 11 to generate the first image 13, and the control unit 4 is configured to perform the following control when the plurality of contrast agent images 11 are imaged while changing the relative position of the imaging unit 10 and the subject 50: the first images 13 corresponding to the respective contrast agent images 11 are sequentially displayed, and the plurality of second images 14 for generating the differential panoramic image 18 are generated by performing the second image processing 34 of reducing the difference in pixel value of the part of the subject common to the contrast agent image 11 and the non-contrast agent image 12. Thus, when a plurality of contrast agent images 11 are captured while changing the relative position of the imaging unit 10 and the subject 50, the first image 13 for sharpening the blood vessel 50a as the imaging target corresponding to each contrast agent image 11 is generated and displayed, and therefore, the user can clearly confirm the movement of the contrast agent in the blood vessel 50a when imaging the contrast agent image 11. Further, by generating the plurality of second images 14 for generating the difference panoramic image 18, the difference image 17 can be generated when the non-contrast agent image 12 is imaged, and therefore the blood vessel 50a can be confirmed when the non-contrast agent image 12 is imaged. As a result, a desired differential panoramic image 18 can be appropriately generated.

In the present embodiment, the image processing unit 3 is configured to: the plurality of third images 15 for generating the differential panoramic image 18 are generated by performing third image processing 35 for reducing the difference in pixel value of the part of the subject 50 common to the contrast agent image 11 and the non-contrast agent image 12 on the plurality of non-contrast agent images 12, and the differential panoramic image 18 is generated from the plurality of second images 14 and the plurality of third images 15. Thus, by reducing the difference in pixel values of the portion of the subject 50 common to the contrast agent image 11 and the non-contrast agent image 12, the difference in pixel values of the portion of the subject 50 common to the contrast agent image 11 in which the blood vessels 50a are clear and the portion of the non-contrast agent image 12 in which the blood vessels 50a are not clear becomes smaller in the second image 14 and the third image 15. Therefore, when the differential panoramic image 18 is generated, the shared portion other than the blood vessel 50a is unclear. As a result, the difference panoramic image 18 with clear blood vessels 50a can be generated.

In the present embodiment, the imaging conditions such as the radiation dose, the imaging start position, and the imaging timing are the same when the contrast medium image 11 and the non-contrast medium image 12 are imaged, and the image processing unit 3 is configured to: the contrast agent image 11 is subjected to gradation processing as the second image processing 34, and the non-contrast agent image 12 is subjected to gradation processing as the third image processing 35. Thus, the imaging conditions of the contrast medium image 11 are the same as those of the non-contrast medium image 12, and therefore the contrast medium image 11 is almost the same as the non-contrast medium image 12 except for the clear distinction of the blood vessel 50 a. Further, by performing gradation processing to adjust the pixel values, the difference in pixel values between the second image 14 and the third image 15 can be reduced. As a result, the portion other than the blood vessel 50a can be reliably obscured when the differential panoramic image 18 is generated.

In the present embodiment, the control unit 4 is configured to perform the following control: when the non-contrast agent image 12 is captured while changing the relative position between the imaging unit 10 and the subject 50, a difference image 17 obtained by subtracting the second image 14 and the third image 15 corresponding to the respective non-contrast agent images 12 is sequentially displayed on the display unit 7. Thus, when the non-contrast agent image 12 is imaged, the differential image 17 in which the blood vessel 50a is clearer than that of the first image 13 can be captured while being checked.

In the present embodiment, the image processing unit 3 is configured to perform the fourth image processing 36 for generating an image representing the outline of a portion other than the blood vessel 50 a. Thus, since the contour of the bone 50b or the like can be grasped, when an abnormality occurs in the generated differential panoramic image 18 due to an external factor, it can be confirmed whether or not there is an abnormality in the third image 15 generated from the same non-contrast agent image 12 by confirming the fourth image 16.

In the present embodiment, the image processing unit 3 is configured to: the same first processing is performed as the first image processing 33 and the fourth image processing 36, and the same second processing is performed as the second image processing 34 and the third image processing 35. Thus, the image processing unit 3 can generate four different images by performing two processes, and therefore, it is possible to suppress the image processing from becoming complicated when four images are generated.

In the present embodiment, the image processing unit 3 includes a first processing unit 31 that performs first processing on the contrast agent image 11 and the non-contrast agent image 12, and a second processing unit 32 that performs second processing on the contrast agent image 11 and the non-contrast agent image 12. Thus, after the contrast agent image 11 and the non-contrast agent image 12 are generated, the first processing unit 31 and the second processing unit 32 perform processing to generate four different images. Therefore, the number of processing units can be reduced compared to the case where processing units are provided for each generated image, and therefore the configuration of the image processing unit 3 can be simplified.

In the present embodiment, the image processing unit 3 is configured to: as the first image processing 33, a defocused image 19 that makes the blood vessel 50a unclear and makes a portion other than the blood vessel 50a clear is generated from the contrast agent image 11, and the first image 13 that makes the blood vessel 50a clear is generated by subtracting the defocused image 19 and the contrast agent image 11. Thus, the blood vessel 50a is clearer in the first image 13 than in the contrast medium image 11, and therefore the user can clearly confirm the flow of the contrast medium when the contrast medium image 11 is captured.

[ modified examples ]

The embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and includes all modifications (variations) within the meaning and scope equivalent to the claims.

For example, although the embodiments described above show an example in which the radiographic apparatus is an X-ray radiographic apparatus, the present invention is not limited to this. In the present invention, the radiographic apparatus may be an imaging apparatus that utilizes radiation such as gamma rays.

In the above-described embodiment, the X-ray fluoroscopic system has been described as an example in which the relative position between the imaging unit and the subject is changed by moving the top plate, but the present invention is not limited to this. In the present invention, the X-ray fluoroscopic system may change the relative position of the imaging unit and the subject by moving the imaging unit.

In the above-described embodiment, the image processing unit is configured to perform the processing of removing the high-frequency component from the contrast medium image using the low-pass filter, but the present invention is not limited to this. In the present invention, for example, the image processing unit may be configured to remove a high-frequency component by using fourier transform.

In the above-described embodiment, the display unit is provided separately from the X-ray fluoroscopic apparatus, but the present invention is not limited to this. In the present invention, the display unit may be disposed in the X-ray fluoroscopic apparatus.

In the above-described embodiment, the example in which the image processing unit is configured to generate the differential panoramic image by joining the differential images has been described, but the present invention is not limited to this. In the present invention, the image processing unit may be configured to: after generating the panoramic image of the second image and the panoramic image of the third image, the panoramic image of the second image and the panoramic image of the third image are subtracted to generate a differential panoramic image.

In addition, in the above-described embodiment, the example in which the first image processing is the same as the fourth image processing and the second image processing is the same as the third image processing is shown, but the present invention is not limited thereto. In the present invention, the first image processing may be different from the fourth image processing, or the second image processing may be different from the third image processing.

In the above-described embodiment, the example in which the image processing section includes the first processing section and the second processing section is shown, but the present invention is not limited to this. In the present invention, the image processing unit may include a first processing unit, a second processing unit, a third processing unit, and a fourth processing unit in accordance with the first image processing, the second image processing, the third image processing, and the fourth image processing.

In the above-described embodiment, the image processing unit is configured to perform the gradation processing by setting the parameters as the second image processing and the third image processing, but the present invention is not limited thereto. For example, the image processing unit may set a threshold value to perform binarization.

In the above-described embodiment, the example in which the image processing unit is configured to simultaneously perform the first image processing and the second image processing has been described, but the present invention is not limited thereto. For example, the image processing unit may be configured to perform the second image processing after the first image processing.

[ means ]

It should be understood by those skilled in the art that the above-described exemplary embodiments are specific examples in the following manner.

(item 1)

A radiographic apparatus includes: an imaging unit including a radiation source that irradiates a subject with radiation, and a detection unit that detects radiation irradiated from the radiation source and transmitted through the subject to acquire a detection signal; an image processing unit that generates a plurality of contrast agent images based on the detection signals acquired at a plurality of relative positions using a contrast agent, generates a plurality of non-contrast agent images based on the detection signals acquired at the plurality of relative positions without using a contrast agent, and generates a differential panoramic image by subtracting and joining the contrast agent images and the non-contrast agent images; and a control unit that performs control of outputting the image generated by the image processing unit and causing a display unit to display the image, wherein the image processing unit is configured to: when the plurality of contrast agent images are captured while changing the relative position of the imaging unit and the subject, the control unit generates a first image by performing first image processing for sharpening blood vessels to be imaged on the plurality of contrast agent images, and generates a plurality of second images for generating the difference panoramic image by performing second image processing for reducing a difference in pixel value between the contrast agent image and the non-contrast agent image in a portion of the subject that is common to the plurality of contrast agent images, the control unit being configured to: when the plurality of contrast agent images are captured while changing the relative position of the imaging unit and the subject, control is performed to sequentially display the first images corresponding to the respective contrast agent images.

(item 2)

The radiographic apparatus according to item 1, wherein the image processing unit is configured to: generating a plurality of third images for generating the differential panoramic image by performing third image processing on the plurality of non-contrast agent images that reduces a difference in pixel value of a portion of the subject that is common in the contrast agent image and the non-contrast agent image, and generating the differential panoramic image from the plurality of second images and the plurality of third images.

(item 3)

The radiographic apparatus according to item 2, wherein the contrast medium image and the non-contrast medium image are imaged under the same imaging conditions such as the radiation dose, the imaging start position, and the imaging timing,

the image processing unit is configured to: the contrast agent image is subjected to gradation processing as the second image processing, and the non-contrast agent image is subjected to gradation processing as the third image processing.

(item 4)

The radiographic apparatus according to item 2 or 3, wherein the control unit is configured to: when the non-contrast agent image is captured while changing the relative position of the imaging unit and the subject, control is performed to sequentially display, on the display unit, a difference image obtained by subtracting the second image and the third image corresponding to each of the non-contrast agent images.

(item 5)

The radiographic apparatus according to any one of items 2 to 4, wherein the image processing unit is configured to perform fourth image processing for generating an image representing an outline of a portion other than a blood vessel.

(item 6)

The radiographic apparatus according to item 5, wherein the image processing unit is configured to: the same first processing is performed as the first image processing and the fourth image processing, and the same second processing is performed as the second image processing and the third image processing.

(item 7)

The radiographic apparatus according to item 6, wherein the image processing unit includes: a first processing unit that performs the first processing on the contrast agent image and the non-contrast agent image; and a second processing unit that performs the second processing on the contrast agent image and the non-contrast agent image.

(item 8)

The radiographic apparatus according to any one of items 1 to 7, wherein the image processing unit is configured to: as the first image processing: generating a defocused image which makes the blood vessels unclear and makes the parts other than the blood vessels clearer from the contrast agent image, and generating the first image which makes the blood vessels clearer by subtracting the defocused image and the contrast agent image.