JP6956554B2 - X-ray diagnostic equipment and image processing program - Google Patents

Description

Embodiments of the present invention relate to an X-ray diagnostic apparatus and an image processing program.

Conventionally, an X-ray diagnostic apparatus has a road map function as a function for supporting a procedure in intervention treatment. The road map function generates a blood vessel image using image data including information on blood vessels collected using a contrast medium, and masks the generated blood vessel image on a fluoroscopic image to display the device in the blood vessel. Support operation.

Further, the X-ray diagnostic apparatus is provided with a filtering function in which X-ray irradiation is controlled by various filters in order to reduce the exposure dose of the subject due to the acquisition of the X-ray image. For example, an X-ray diagnostic apparatus can emit X-rays to an area other than the area of interest as compared with the dose of X-rays emitted to the area of interest including a site to be treated or a medical device. The filtering function that controls the dose to be low reduces the exposure dose of the subject while generating a clear X-ray image for the region of interest.

Japanese Unexamined Patent Publication No. 2000-342565 Japanese Unexamined Patent Publication No. 2005-34259 Japanese Unexamined Patent Publication No. 2014-12216 Japanese Unexamined Patent Publication No. 2010-279594 Japanese Patent No. 2013-090965

An object to be solved by the present invention is to provide an X-ray diagnostic apparatus and an image processing program capable of improving the efficiency of interventional treatment.

The X-ray diagnostic apparatus of the embodiment includes a first collecting unit, a second collecting unit, a third collecting unit, an acquiring unit, and a generating unit. The first collection unit collects a first X-ray image based on the X-rays applied to the subject at the first dose. The second collecting unit collects a second X-ray image based on the X-rays applied to the subject at a second dose lower than the first dose. The third collection unit collects a third X-ray image based on X-rays irradiated with different doses to the region of interest of the subject into which the medical device is inserted and the region other than the region of interest. .. The acquisition unit acquires the position information of the region of interest in the third X-ray image. Based on the position information, the generation unit acquires the positions corresponding to the regions of interest in the first X-ray image and the second X-ray image, respectively, and the generation unit obtains the regions of interest in the third X-ray image. Is different from the region corresponding to the region of interest in the first X-ray image, and the region other than the region of interest in the third X-ray image and the region other than the region of interest in the second X-ray image. Generates a difference image that is different from the area corresponding to.

FIG. 1 is a block diagram showing an example of the configuration of the X-ray diagnostic apparatus according to the first embodiment. FIG. 2 is a diagram for explaining a perspective roadmap according to the first embodiment. FIG. 3 is a diagram for explaining a perspective image, a wire mask image, and a difference image according to the first embodiment. FIG. 4 is a diagram for explaining a wire mask image according to the first embodiment. FIG. 5A is a diagram showing an example in which the position of the region of interest according to the first embodiment moves. FIG. 5B is a diagram for explaining a wire mask image and a difference image when the position of the region of interest according to the first embodiment moves. FIG. 6 is a flowchart for explaining a series of processes of the X-ray diagnostic apparatus according to the first embodiment. FIG. 7 is a diagram for explaining a perspective roadmap according to the second embodiment. FIG. 8 is a flowchart for explaining a series of processes of the X-ray diagnostic apparatus according to the second embodiment. FIG. 9 is a diagram for explaining a perspective roadmap according to the third embodiment. FIG. 10 is a diagram for explaining a perspective roadmap according to a third embodiment.

Hereinafter, the X-ray diagnostic apparatus and the image processing program according to the embodiment will be described with reference to the drawings. The X-ray diagnostic apparatus and the image processing program according to the present application are not limited to the following embodiments.

First, an example of the configuration of the X-ray diagnostic apparatus 100 according to the first embodiment will be described with reference to FIG. FIG. 1 is a block diagram showing an example of the configuration of the X-ray diagnostic apparatus 100 according to the first embodiment. As shown in FIG. 1, the X-ray diagnostic apparatus 100 according to the first embodiment includes a high voltage generator 11, an X-ray tube 12, a collimator 13a, a filter 13b, a top plate 14, and a C-arm 15. And an X-ray detector 16. Further, the X-ray diagnostic apparatus 100 according to the first embodiment includes a C-arm rotation / movement mechanism 17, a top plate movement mechanism 18, a C-arm / top plate mechanism control circuit 19, and a collimator / filter control circuit 20. , A processing circuit 21, an input circuit 22, and a display 23. Further, the X-ray diagnostic apparatus 100 according to the first embodiment includes an image data generation circuit 24, a storage circuit 25, and an image processing circuit 26. Further, the X-ray diagnostic apparatus 100 is connected to the injector 30. Then, as shown in FIG. 1, in the X-ray diagnostic apparatus 100, each circuit is connected to each other, and various electric signals are transmitted / received between the circuits, or an electric signal is transmitted / received to / from the injector 30.

The injector 30 is a device for injecting a contrast medium from a catheter inserted into the subject P. Here, the injection of the contrast medium from the injector 30 is executed according to the injection instruction received via the processing circuit 21 described later. Specifically, the injector 30 executes the injection start instruction of the contrast medium received from the processing circuit 21 described later, the injection stop instruction, and the contrast medium injection according to the contrast medium injection conditions including the injection speed and the like. The injector 30 can also start or stop injection according to an injection instruction directly input to the injector 30 by the operator.

In the X-ray diagnostic apparatus 100 shown in FIG. 1, each processing function is stored in the storage circuit 25 in the form of a program that can be executed by a computer. The C-arm / top plate mechanism control circuit 19, the collimator / filter control circuit 20, the processing circuit 21, the image data generation circuit 24, and the image processing circuit 26 are assigned to each program by reading the program from the storage circuit 25 and executing the program. It is a processor that realizes the corresponding functions. In other words, each circuit in the state where each program is read has a function corresponding to the read program.

The word "processor" used in the above description is, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), an integrated circuit for a specific application (ASIC), or a programmable logic medical device. (For example, a circuit such as a simple programmable logic device (SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). do. The processor realizes the function by reading and executing the program stored in the storage circuit 25. Instead of storing the program in the storage circuit 25, the program may be directly incorporated in the circuit of the processor. In this case, the processor realizes the function by reading and executing the program embedded in the circuit. It should be noted that each processor of the present embodiment is not limited to the case where each processor is configured as a single circuit, and a plurality of independent circuits may be combined to form one processor to realize its function. good.

The collection function 211 in the first embodiment is an example of a first collection unit, a second collection unit, and a third collection unit within the scope of claims. Further, the acquisition function 212 in the first embodiment is an example of an acquisition unit within the scope of claims. Further, the generation function 213 in the first embodiment is an example of a generation unit within the scope of claims. Further, the display control function 214 in the first embodiment is an example of a display control unit within the scope of claims. Further, the filter control function 215 in the first embodiment is an example of a filter control unit within the scope of claims.

The high voltage generator 11 generates a high voltage under the control of the processing circuit 21, and supplies the generated high voltage to the X-ray tube 12. The X-ray tube 12 generates X-rays by using the high voltage supplied from the high voltage generator 11. Under the control of the collimator filter control circuit 20, the collimator 13a narrows down the X-rays generated by the X-ray tube 12 so as to selectively irradiate the area to be collected with the X-ray image. For example, the collimator 13a has four sliding diaphragm blades. The collimator 13a slides these diaphragm blades under the control of the collimator filter control circuit 20 to narrow down the X-rays generated by the X-ray tube 12 and irradiate the subject P. The diaphragm blade is a plate-shaped member made of lead or the like, and is provided near the X-ray irradiation port of the X-ray tube 12 in order to adjust the X-ray irradiation range.

The filter 13b is an X-ray filter for adjusting the X-rays exposed from the X-ray tube 12. For example, the filter 13b changes the quality of X-rays transmitted depending on the material and thickness of the filter 13b for the purpose of reducing the exposure dose to the subject P and improving the image quality of the image data, and obtains a soft ray component that is easily absorbed by the subject P. It reduces or reduces high-energy components that cause a decrease in contrast of X-ray images.

Further, the filter 13b changes the dose and irradiation range of X-rays according to its material, thickness, position, etc., so that the X-rays irradiated from the X-ray tube 12 to the subject P have a predetermined distribution. Attenuate the line. For example, the filter 13b distributes the X-ray dose so that the region of interest in the region for collecting the X-ray image in the subject P has a high dose and the region other than the region of interest has a low dose. It functions as a controlling ROI (Region Of Interest) filter. Further, for example, the filter 13b functions as an X-ray filter that controls the distribution of the X-ray dose so that the X-ray dose is uniform over the entire surface of the region where the X-ray image is collected in the subject P.

For example, the filter 13b has an opening for partially transmitting X-rays without attenuating them. That is, the filter 13b has a region for attenuating the transmitted X-rays at an attenuation rate according to the material and the thickness (hereinafter, also referred to as a first region) and an opening for transmitting the X-rays without being attenuated. Have. In this case, the X-rays radiated to the subject P through the opening have a higher dose than the X-rays radiated to the subject P through the first region.

Further, for example, the filter 13b has a first region and a region for attenuating X-rays transmitted through the first region at a lower attenuation rate than the X-rays transmitted through the first region (hereinafter, also referred to as a second region). Have. The second region is configured to have a smaller thickness in the X-ray irradiation direction than, for example, the first region. Further, for example, the second region is made of a material having a smaller X-ray absorption coefficient than the first region.

Here, the filter 13b can control the distribution of the X-ray dose by moving through the aperture or the second region. Hereinafter, control of the X-ray dose distribution by the filter 13b will be described. In the following, a case where the opening or the second region is moved by moving the filter 13b will be described. Further, in the following, a case where the filter 13b has an opening for transmitting X-rays without being attenuated will be described as an example.

For example, the filter 13b moves in the direction of contact and separation from the X-ray tube 12 by the collimator filter control circuit 20 under the control of the processing circuit 21. That is, the filter 13b moves in the direction in which the opening is brought into contact with and separated from the X-ray tube 12 by moving the filter 13b itself.

When the X-ray irradiation range includes an opening, a part of the X-ray emitted from the X-ray tube 12 is irradiated to the subject P through the opening, and a part is attenuated by the filter 13b to the subject P. Be irradiated. In this case, the filter 13b distributes the X-ray dose so that the region of interest in the region for collecting the X-ray image in the subject P has a high dose and the region other than the region of interest has a low dose. Functions as an ROI filter that controls. Here, as the distance between the opening and the X-ray tube 12 increases, the region where the high-dose X-ray is irradiated through the opening becomes smaller. That is, the filter 13b can control the size of the region of interest by moving the opening in the direction of contacting and separating from the X-ray tube 12.

Further, the filter 13b is moved by the collimator filter control circuit 20 in a direction perpendicular to the direction of contact and separation with the X-ray tube 12 under the control of the processing circuit 21. Thereby, the filter 13b can control the position of the region of interest. Further, the filter 13b moves so that the X-ray irradiation range does not include an opening, so that all the X-rays emitted from the X-ray tube 12 are attenuated by the filter 13b and irradiated to the subject P. To control. In this case, the filter 13b functions as an X-ray filter that controls the entire surface of the region where the X-ray image is collected in the subject P to be irradiated with low-dose X-rays. Further, by moving the filter 13b so as not to be included in the X-ray irradiation range, it is possible to irradiate the entire surface of the region for collecting the X-ray image in the subject P with a high-dose X-ray. The control of the X-ray dose distribution by the filter 13b described above is the same even when the filter 13b has a second region instead of the opening.

The top plate 14 is a bed on which the subject P is placed, and is arranged on a bed (not shown). The subject P is not included in the X-ray diagnostic apparatus 100. The X-ray detector 16 detects the X-rays that have passed through the subject P. For example, the X-ray detector 16 has detection elements arranged in a matrix. Each detection element converts X-rays transmitted through the subject P into an electric signal, stores the X-ray, and transmits the stored electric signal to the image data generation circuit 24.

The C-arm 15 holds an X-ray tube 12, a collimator 13a, a filter 13b, and an X-ray detector 16. The X-ray tube 12, the collimator 13a, the filter 13b, and the X-ray detector 16 are arranged so as to face each other with the subject P sandwiched by the C arm 15. In FIG. 1, the case where the X-ray diagnostic apparatus 100 is a single plane is described as an example, but the embodiment is not limited to this, and may be a biplane case.

The C-arm rotation / movement mechanism 17 is a mechanism for rotating and moving the C-arm 15, and the top plate moving mechanism 18 is a mechanism for moving the top plate 14. The C-arm / top plate mechanism control circuit 19 controls the C-arm rotation / movement mechanism 17 and the top plate movement mechanism 18 under the control of the processing circuit 21 to rotate and move the C-arm 15 and the top plate 14. Adjust the movement. The collimator / filter control circuit 20 controls the irradiation range of X-rays applied to the subject P by adjusting the opening degree of the diaphragm blades of the collimator 13a under the control of the processing circuit 21. Further, the collimator / filter control circuit 20 controls the distribution of the dose of X-rays irradiated to the subject P by adjusting the position of the filter 13b under the control of the processing circuit 21.

The image data generation circuit 24 generates image data using an electric signal converted from X-rays by the X-ray detector 16, and stores the generated image data in the storage circuit 25. For example, the image data generation circuit 24 generates image data by performing current / voltage conversion, A (Analog) / D (Digital) conversion, and parallel / serial conversion on the electric signal received from the X-ray detector 16. do. As an example, the image data generation circuit 24 generates image data of a fluoroscopic image including the position and shape of a medical device over time during a procedure in endovascular treatment. Further, for example, the image data generation circuit 24 is based on image data based on X-rays transmitted through a subject P in which a contrast medium has not been injected and X-rays transmitted through a subject P in which a contrast medium has been injected. Generate image data. Further, to give an example, the image data generation circuit 24 generates various image data used for generating a wire mask image described later. Then, the image data generation circuit 24 stores the generated image data in the storage circuit 25.

The storage circuit 25 receives and stores the image data generated by the image data generation circuit 24. For example, the storage circuit 25 may include image data based on X-rays transmitted through a subject P in which a contrast medium has not been injected, image data based on X-rays transmitted through a subject P injected with a contrast medium, and a wire mask described later. Stores image data and the like used to generate images. Further, for example, the storage circuit 25 can store all or a part of the image data of the fluoroscopic image. Further, the storage circuit 25 stores programs corresponding to various functions read and executed by each circuit shown in FIG. As an example, the storage circuit 25 includes a program corresponding to the collection function 211 read and executed by the processing circuit 21, a program corresponding to the acquisition function 212, a program corresponding to the generation function 213, a display control function 214, and the display control function 214. The program corresponding to the filter control function 215 is stored.

The image processing circuit 26 performs various image processing on the image data stored in the storage circuit 25. For example, the image processing circuit 26 generates a difference image by subtracting the image data of the fluoroscopic image based on the X-ray transmitted through the subject P into which the medical device is inserted and the wire mask image described later. Further, for example, the image processing circuit 26 is based on image data based on X-rays transmitted through the subject P before the contrast medium is injected and X-rays transmitted through the subject P after the contrast medium is injected. An image of a blood vessel is generated by reading out the image data from the storage circuit 25 and subtracting the image data.

The image processing circuit 26 can perform scattered ray correction on the image data of the perspective image, the image data used for generating the wire mask image described later, and the like. Further, the image processing circuit 26 can also execute noise reduction processing by an image processing filter such as a moving average (smoothing) filter, a Gaussian filter, and a median filter. Further, the image processing circuit 26 can minimize the error of the alignment (registration) due to the body movement by using one frame immediately before the administration of the contrast medium as a mask image. That is, the image processing circuit 26 can execute preprocessing including noise removal and misalignment correction for each of the collected X-ray images.

The input circuit 22 is realized by a trackball, a switch button, a mouse, a keyboard, etc. for performing various instructions and various settings. The input circuit 22 is connected to the processing circuit 21, converts the input operation received from the operator into an electric signal, and outputs the input operation to the processing circuit 21. The display 23 displays a GUI (Graphical User Interface) for receiving instructions from the operator and various X-ray images generated by the image processing circuit 26. For example, the display 23 displays a difference image in which background components such as bones are different from a fluoroscopic image sequentially generated during a procedure under the control of a processing circuit 21, and a blood vessel displayed overlaid (masked) on the difference image. Display various X-ray images such as images.

The processing circuit 21 controls the operation of the entire X-ray diagnostic apparatus 100 by executing the collection function 211, the acquisition function 212, the generation function 213, the display control function 214, and the filter control function 215. For example, the processing circuit 21 executes various processes by reading a program for controlling the entire device from the storage circuit 25 and executing the program. For example, the processing circuit 21 controls the high voltage generator 11 according to the instruction of the operator transferred from the input circuit 22, and adjusts the voltage supplied to the X-ray tube 12 to irradiate the subject P. X-ray dose and ON / OFF are controlled. Further, for example, the processing circuit 21 controls the C-arm / top plate mechanism control circuit 19 according to the instruction of the operator, and adjusts the rotation and movement of the C-arm 15 and the movement of the top plate 14. Further, for example, the processing circuit 21 controls the collimator / filter control circuit 20 according to the instruction of the operator, and adjusts the opening degree of the diaphragm blades of the collimator 13a to irradiate the subject P with X-rays. Control the irradiation range of.

Further, for example, the processing circuit 21 reads the program corresponding to the filter control function 215 from the storage circuit 25 and executes it to control the collimator / filter control circuit 20 according to the instruction of the operator and adjust the position of the filter 13b. By doing so, the dose of X-rays irradiated to the subject P is controlled, and the irradiation range of X-rays is controlled for each dose. That is, the processing circuit 21 controls the distribution of the X-ray dose through the control of the collimator / filter control circuit 20.

Further, the processing circuit 21 controls the image data generation processing by the image data generation circuit 24, the image processing by the image processing circuit 26, and the like according to the instruction of the operator. Further, the processing circuit 21 controls the GUI for receiving the instruction of the operator, the image stored in the storage circuit 25, and the like to be displayed on the display 23. Further, the processing circuit 21 controls the injection timing of the contrast medium by transmitting signals for starting and ending the injection of the contrast medium to the injector 30. Each function of the processing circuit 21 will be described in detail later.

The example of the configuration of the X-ray diagnostic apparatus 100 has been described above. Under such a configuration, the X-ray diagnostic apparatus 100 according to the present embodiment improves the efficiency of intervention treatment by processing by the processing circuit 21 described in detail below. Specifically, the X-ray diagnostic apparatus 100 displays only the medical device while operating the ROI filter by generating a wire mask image that follows the movement of the region of interest (ROI) in fluoroscopy using the ROI filter. Allows the generation of differential images to improve the efficiency of treatment. Here, the wire mask image is an image necessary for displaying only a medical device such as a catheter for blood vessel running on a fluoroscopic roadmap. In addition, the X-ray diagnostic apparatus 100 enables a fluoroscopic roadmap that masks and displays a blood vessel image that displays blood vessel running on a difference image that displays a medical device while operating an ROI filter, thereby enabling treatment efficiency. To improve. Hereinafter, the processing performed by the X-ray diagnostic apparatus 100 according to the first embodiment will be described in detail.

First, a fluoroscopic roadmap while operating the ROI filter by the X-ray diagnostic apparatus 100 will be described with reference to FIG. FIG. 2 is a diagram for explaining a perspective roadmap according to the first embodiment. First, the X-ray diagnostic apparatus 100 collects a blood vessel image using a contrast medium. For example, the collection function 211 collects an X-ray image I1 representing a peripheral tissue (background) such as a bone in a state where the contrast medium is not injected into the subject P. In addition, the collection function 211 collects an X-ray image I2 including the position and shape of a blood vessel while the contrast medium is injected into the subject P. As an example, the collection function 211 transmits the X-rays transmitted through the subject P after the contrast medium is injected by injecting the contrast medium by the injector 30 at the time of collecting the X-ray image I2. Based on the X-ray image I2 is collected. Then, the collection function 211 stores the collected X-ray image I1 and X-ray image I2 in the storage circuit 25. Here, the collection function 211 controls the image processing circuit 26 to perform scattered ray correction, beam hardening correction, and the like on the collected X-ray image I1 and X-ray image I2, and then causes the storage circuit 25 to perform the scattered ray correction, the beam hardening correction, and the like. It can also be stored.

Next, the generation function 213 controls the image processing circuit 26 to generate the blood vessel image I3 using the X-ray image I1 and the X-ray image I2 as shown in FIG. For example, the generation function 213 reads out the X-ray image I1 and the X-ray image I2 from the storage circuit 25, and by differentiating the read X-ray image I1 and the X-ray image I2, the background element is removed and the blood vessel is formed. Generates an enhanced vascular image I3.

In the following, a case where the collection function 211 collects the X-ray image I1 and the X-ray image I2 shown in FIG. 2 as “photographed images” will be described. A "photographed image" is an X-ray image collected by a high dose of X-rays as compared to a "perspective image". Further, a case where the generation function 213 generates a blood vessel image I3 which is a DSA (Digital Subtraction Angiography) image by differentiating the X-ray image I1 and the X-ray image I2 will be described below. That is, the generation function 213 generates the blood vessel image I3 used for the fluoroscopy roadmap from the captured image collected prior to the fluoroscopy.

Next, as shown in FIG. 2, the X-ray diagnostic apparatus 100 differentiates the fluoroscopic image I4 and the wire mask image I5, which are sequentially generated during the intervention treatment procedure, to provide a background component other than the medical device. The difference image I6 excluding the above is generated. Then, as shown in FIG. 2, the generation function 213 generates a superposed image I7 in which the blood vessel image I3 and the difference image I6 are superimposed. Here, the generation function 213 generates the superimposed image I7 by superimposing the X-ray image whose pixel value of the blood vessel image I3 is adjusted so that the medical device superimposed on the blood vessel can be visually recognized and the difference image I6. You can also do it. Alternatively, as shown in FIG. 2, the generation function 213 generates a superposed image I8 in which the background component of the subject P is superposed on the superposed image I7. In the generation function 213, the X-ray image I1 and the wire mask image I5 shown in FIG. 2 may be used as the background component of the subject P in the superimposed image I8, or the X-ray image (not shown) may be used as the background component of the subject P in the superimposed image I8. It may be used as a background component of.

Here, the perspective image I4, the wire mask image I5, and the difference image I6 will be described with reference to FIG. FIG. 3 is a diagram for explaining the perspective image I4, the wire mask image I5, and the difference image I6 according to the first embodiment. Note that FIG. 3 shows a case where a medical device is inserted into a blood vessel of the head of the subject P for treatment.

The collection function 211 collects a plurality of fluoroscopic images I4 over time at a predetermined frame rate during the intervention treatment procedure. Here, as shown in FIG. 3, the collection function 211 uses X-rays controlled so as to irradiate the region R1 of interest and the region R2 other than the region of interest with different doses, and the fluoroscopic image I4. To collect. Specifically, the filter control function 215 controls the position of the filter 13b so that the filter 13b for reducing the dose is applied to the region R2. Then, the collection function 211 collects the fluoroscopic image I4 in which the dose to the region R2 is reduced as compared with the region R1 of interest. Then, the collection function 211 controls the image processing circuit 26 to execute correction processing such as scattering ray correction on the fluoroscopic images I4 sequentially collected.

In the following, the dose of X-rays applied to the region of interest R1 in the acquisition of the fluoroscopic image I4 is also referred to as the first dose. Further, in the following, the dose of X-rays irradiated to the region R2 other than the region of interest in the acquisition of the fluoroscopic image I4 is also described as the second dose. Here, the second dose is at least lower than the first dose. For example, only the X-rays applied to the region R2 pass through the filter 13b and are attenuated, so that the second dose becomes lower than the first dose. Further, for example, the X-rays radiated to the region R2 pass through the thick portion of the filter 13b, and the X-rays radiated to the region R1 of interest pass through the thin portion of the filter 13b, so that the region R2 is irradiated. The X-rays are more attenuated and the second dose is lower than the first dose.

Next, as shown in FIG. 3, the generation function 213 removes background components other than the medical device from the fluoroscopic image I4 by differentiating the fluoroscopic image I4 and the wire mask image I5, and the medical device in the blood vessel Generates the highlighted difference image I6. Here, the wire mask image I5 is an X-ray image in which at least one image is generated prior to the generation of the fluoroscopic image I4 in order to generate the difference image I6.

Here, in order to generate the difference image I6 in which components other than the medical device are removed as much as possible, the dose of X-rays irradiated to the region R1 of the wire mask image I5 and the region R2 other than the region of interest is set, respectively. , It is preferable to match the dose of X-rays when collecting the fluoroscopic image I4. Further, it is preferable that the position of the region of interest R1 in the wire mask image I5 matches the position of the region of interest R1 in the perspective image I4. That is, in order to remove the background component from the fluoroscopic image I4 by the difference and generate the differential image I6 in which the components other than the medical device are removed as much as possible, the fluoroscopic image I4 and the wire mask image I5 are used at each position on the image. The image quality is required to be similar.

Hereinafter, the collection of the wire mask image I5 will be described with reference to FIG. FIG. 4 is a diagram for explaining the wire mask image I5 according to the first embodiment. First, the collection function 211 collects an X-ray image I51 (hereinafter, also referred to as a first X-ray image) based on the X-rays irradiated to the subject P at the first dose. That is, the collection function 211 collects the entire X-ray image I51 under the X-ray condition of the region of interest R1 in the fluoroscopic image I4. In addition, the collection function 211 collects an X-ray image I52 (hereinafter, also referred to as a second X-ray image) based on the X-rays irradiated to the subject P at the second dose. That is, the collection function 211 collects the entire X-ray image I52 under the X-ray conditions of the region R2 other than the region of interest in the fluoroscopic image I4. In the following, the fluoroscopic image I4 will also be referred to as a third X-ray image.

Further, as shown in FIG. 4, the collecting function 211 collects the X-ray image I53 based on the X-rays irradiated to the region R1 of interest and the region R2 other than the region of interest at different doses. Here, the collecting function 211 collects the X-ray image I53 so that the position of the region of interest R1 in the X-ray image I53 is the same as the position of the region of interest R1 in the perspective image I4. For example, the collection function 211 sets the positions of the X-ray tube 12, the collimator 13a, the filter 13b, the subject P, and the like to be the same for the collection of the fluoroscopic image I4 and the collection of the X-ray image I53 so that the X-ray image is the same. Collect I53.

Then, the acquisition function 212 acquires the position information of the region of interest R1 from the X-ray image I53. Since the X-ray image I53 described above is an image collected by irradiating the region R1 and the region R2 with different doses of X-rays, the pixel values differ greatly between the region R1 and the region R2. Therefore, the acquisition function 212 identifies the boundary between the region R1 and the region R2 based on the pixel value of the X-ray image I53, and acquires the position information of the region R1 of interest in the X-ray image I53. Here, since the position of the region of interest R1 is the same for the X-ray image I53 and the perspective image I4, the acquisition function 212 acquires the position information of the region of interest R1 in the perspective image I4. The acquisition function 212 acquires the position information every time the position of the region R1 of interest is changed. This point will be described later.

The collection function 211 may be used to collect the X-ray image I53 at a dose different from the X-ray dose in the collection of the fluoroscopic image I4. As an example, the collection function 211 irradiates the region R1 with an X-ray having a dose lower than the first dose and an X-ray irradiating the region R2 other than the region R2 with a dose lower than the second dose. X-ray image I53 is collected based on. That is, as long as the acquisition function 212 can acquire the position information of the region R1, the collection function 211 may collect the X-ray image I53 using X-rays of any dose.

Next, the generation function 213 generates the wire mask image I5 based on each X-ray image shown in the upper part of FIG. For example, the generation function 213 first acquires a position corresponding to the region of interest R1 in the X-ray image I51 and the X-ray image I52, respectively. Then, the generation function 213 generates the wire mask image I5 based on the position information corresponding to the region of interest R1 in the X-ray image I51 and the X-ray image I52, the X-ray image I51, and the X-ray image I52. .. As an example, the generation function 213 first extracts a region corresponding to the region of interest R1 from the X-ray image I51. Further, the generation function 213 extracts a region corresponding to the region R2 other than the region of interest from the X-ray image I52. Then, the generation function 213 can generate the wire mask image I5 as shown in FIG. 4 by synthesizing the regions extracted from the X-ray image I51 and the X-ray image I52, respectively.

When the wire mask image I5 is generated in this way, the generation function 213 sequentially generates a difference image I6 in which the plurality of perspective images I4 sequentially generated by fluoroscopy and the wire mask image I5 are different from each other. Then, the generation function 213 generates a superposed image I7 in which the blood vessel image I3 and the difference image I6 are superposed, or a superposed image I8 in which the background component of the subject P is superposed on the superposed image I7.

The display control function 214 causes the superimposed image I7 and the superimposed image I8 to be displayed on the display 23. For example, the display control function 214 supports the operation of the device in the blood vessel by displaying the superimposed image I7 and the superimposed image I8 on the display 23 as a moving image in real time and presenting the superimposed image I7 to the operator. In addition, the display control function 214 includes a fluoroscopic submode that presents an X-ray image showing a blood vessel and a medical device, a landmark mode that presents an X-ray image showing a peripheral tissue in addition to the blood vessel and the medical device, and the like. In this case, the superimposed image I7 and the superimposed image I8 may be switched and displayed on the display 23 according to the mode switching of.

As described above, the X-ray diagnostic apparatus 100 according to the first embodiment generates a wire mask image I5 based on the position of the region of interest R1, and generates a difference image I6 using the generated wire mask image I5. Further, the X-ray diagnostic apparatus 100 uses the difference image I6 generated in this way to execute a perspective roadmap for displaying the superimposed image I7 and the superimposed image I8. Here, the X-ray diagnostic apparatus 100 executes a fluoroscopic roadmap that follows a change in the position of the region of interest R1. Hereinafter, the case where the position of the region of interest R1 changes will be described with reference to FIGS. 5A and 5B. FIG. 5A is a diagram showing an example in which the position of the region of interest R1 according to the first embodiment moves. Further, FIG. 5B is a diagram for explaining the wire mask image I5 and the difference image I6 when the position of the region of interest R1 according to the first embodiment moves.

For example, if the position of the region of interest R1 is improperly set while advancing the medical device to the treatment target site or before the start of the procedure, the tip of the device is the region of interest as shown in the fluoroscopic image I4 of the left figure of FIG. 5A. It is assumed that the vehicle will come out of R1. Here, the region R2 other than the region of interest is seen through at a lower dose than the region of interest R1 and is less clear than the region of interest R1, so that the efficiency of the procedure is reduced. In such a case, it is necessary to shift the position of the region of interest R1 according to the movement of the tip of the medical device. For example, when moving the position of the region of interest R1 in the perspective image I4, the processing circuit 21 receives an instruction to move the position of the region of interest R1 via the input circuit 22. Next, the processing circuit 21 moves the position of the filter 13b according to the content of the instruction to move the position of the region of interest R1 as shown in the perspective image I4 of the right figure of FIG. 5A.

Here, even after the position of the region of interest R1 in the perspective image I4 is moved, in order to generate the difference image I6 in which the background components other than the medical device are different, the position of the region of interest R1 in the wire mask image I5 is a perspective image. It is required to update the wire mask image I5 so as to match the position of the region of interest R1 in I4 after the movement.

Here, the X-ray diagnostic apparatus 100 updates the wire mask image I5 by using the already collected X-ray image I51 and X-ray image I52. First, the acquisition function 212 acquires the position information of the region of interest R1 after movement in the perspective image I4 shown in FIG. 5B. For example, the acquisition function 212 can acquire the position information of the region of interest R1 after movement based on the content of the movement instruction of the region of interest R1 received from the operator via the input circuit 22.

Next, the generation function 213 is shown in FIG. 5B based on the position information corresponding to the region of interest R1 after movement in the X-ray image I51 and the X-ray image I52, the X-ray image I51, and the X-ray image I52. The shown wire mask image I5 is generated. As an example, the generation function 213 first extracts a region of the X-ray image I51 corresponding to the region of interest R1 after movement. In addition, the generation function 213 extracts a region corresponding to the region R2 other than the region of interest after movement from the X-ray image I52. Then, the generation function 213 can generate the wire mask image I5 after the position of the region of interest R1 has moved by synthesizing the regions extracted from the X-ray image I51 and the X-ray image I52, respectively.

Then, as shown in FIG. 5B, the generation function 213 creates a difference image I6 representing a medical device by differentiating the perspective image I4 after the position of the region of interest R1 has moved and the updated wire mask image I5. Generate. Further, the generation function 213 generates a superposed image I7 in which the difference image I6 based on the updated wire mask image I5 and the blood vessel image I3 are superimposed. Alternatively, the generation function 213 generates a superimposed image I8 in which the background component of the subject P is superimposed on the superimposed image I7. Then, the display control function 214 causes the display 23 to display the superimposed image I7 and the superimposed image I8 after the position of the region of interest R1 has moved.

Next, an example of the processing procedure by the X-ray diagnostic apparatus 100 will be described with reference to FIG. FIG. 6 is a flowchart for explaining a series of processes of the X-ray diagnostic apparatus 100 according to the first embodiment. Step S102, step S104, step S105 and step S108 are steps corresponding to the collection function 211. Step S106 is a step corresponding to the acquisition function 212. Step S103, step S107, step S109 and step S110 are steps corresponding to the generation function 213. Step S111 is a step corresponding to the display control function 214.

First, the processing circuit 21 determines whether or not the inspection start command has been accepted (step S101), and if it does not accept the start command, it goes into a standby state (step S101 negative). On the other hand, when the start command is received (affirmation in step S101), the processing circuit 21 includes an X-ray image based on X-rays transmitted through the subject P before the contrast medium is injected and an X-ray image after the contrast medium is injected. An X-ray image based on the X-ray transmitted through the subject P is collected (step S102). Further, the processing circuit 21 generates a blood vessel image by differentiating the X-ray images before and after the injection of the contrast medium (step S103).

Next, the processing circuit 21 irradiates the subject P with X-rays at the first dose and collects the first X-ray image (step S104). Further, the processing circuit 21 irradiates the subject P with X-rays at a second dose and collects a second X-ray image (step S105). Further, the processing circuit 21 acquires the position information of the region of interest R1 from the X-ray images collected based on the X-rays irradiated with different doses to the region of interest R1 and the region R2 other than the region of interest (step). S106). Then, the processing circuit 21 generates a wire mask image based on the first X-ray image, the second X-ray image, and the position information of the region of interest R1 (step S107).

When the device insertion into the blood vessel is started, the processing circuit 21 controls the filter 13b to irradiate the region of interest R1 with X-rays at the first dose, and the region R2 other than the region of interest is the first. Irradiate X-rays at the dose of 2 and collect a third X-ray image over time (step S108). Next, the processing circuit 21 generates a difference image obtained by difference between each third X-ray image collected over time and the wire mask image over time (step S109). Then, the processing circuit 21 generates a superposed image in which the blood vessel image and the difference image are superimposed with time (step S110), and displays the superimposed image on the display 23 (step S111).

Here, the processing circuit 21 determines whether or not the position of the region of interest R1 has been moved (step S112). When the position of the region of interest R1 is moved (affirmation in step S112), the processing circuit 21 shifts to step S106, acquires the position information of the region of interest R1 after the movement, and updates the wire mask image. On the other hand, when the position of the region of interest R1 is not moved (denial in step S112), the processing circuit 21 determines whether or not the inspection end command has been accepted (step S113), and if it does not accept the end command, it goes into a standby state. (Negation of step S113). On the other hand, when the end command is received (step S113 affirmative), the processing circuit 21 ends the processing.

As described above, according to the first embodiment, the collection function 211 collects a first X-ray image based on the X-rays applied to the subject P at the first dose. In addition, the collection function 211 collects a second X-ray image based on the X-rays irradiated to the subject P at a second dose lower than the first dose. Further, the collection function 211 is based on the X-rays irradiated with the first dose and the second dose to the region R1 of interest and the region R2 other than the region of interest of the subject P into which the medical device is inserted, respectively. A third X-ray image is collected. Further, the acquisition function 212 acquires the position information of the region of interest R1 in the third X-ray image. Further, the generation function 213 acquires the position corresponding to the region of interest R1 in the first X-ray image and the second X-ray image, respectively, based on the position information of the region of interest R1 in the third X-ray image. The region of interest R1 in the third X-ray image and the region corresponding to the region of interest R1 in the first X-ray image are differentiated into the region R2 in the third X-ray image and the region R2 in the second X-ray image. Generate a difference image that is different from the corresponding area. Therefore, the X-ray diagnostic apparatus 100 according to the first embodiment operates the ROI filter in fluoroscopy, and even when X-rays having different doses are irradiated in the region R1 of interest and the region R2 other than the region of interest. , It is possible to generate an X-ray image of a medical device in which background components are differentiated and removed. Further, the X-ray diagnostic apparatus 100 presents the X-ray image of the medical device to the operator in fluoroscopy with the ROI filter operated, thereby reducing the exposure dose of the subject P and improving the efficiency of intervention treatment. Can be improved.

Further, according to the first embodiment, the X-ray diagnostic apparatus 100 presents to the operator a superposed image I7 in which a difference image I6 displaying a medical device and a blood vessel image I3 displaying blood vessel running are superimposed. Alternatively, the X-ray diagnostic apparatus 100 presents the superimposed image I8 in which the background component is superimposed on the superimposed image I7 to the operator. Therefore, the X-ray diagnostic apparatus 100 according to the first embodiment operates a ROI filter to reduce the exposure dose of the subject P, and presents the position and shape of the blood vessel running and the medical device to the operator. Maps can be run to improve the efficiency of interventional treatments.

Further, the generation function 213 according to the first embodiment uses the position information of the region of interest R1 to cover the region corresponding to the region of interest R1 in the first X-ray image I51 and the region of interest in the second X-ray image I52. The wire mask image I5 is generated by synthesizing the region corresponding to the region R2 other than the region. Therefore, the X-ray diagnostic apparatus 100 according to the first embodiment easily updates the wire mask image I5 by acquiring the position information of the region of interest R1 even when the position of the region of interest R1 moves, and the intervention. The efficiency of treatment can be improved.

Further, the generation function 213 according to the first embodiment is a wire mask based on the first X-ray image I51 and the second X-ray image I52 that have already been collected when the position of the region of interest R1 moves. Image I5 is updated. Therefore, the X-ray diagnostic apparatus 100 according to the first embodiment does not need to collect the X-ray image again in order to update the wire mask image, and can reduce the exposure dose of the subject P.

In the above-described embodiment, the case where the X-ray image I1 and the X-ray image I2 are collected as the “photographed image” and the blood vessel image I3 is generated as the “DSA image” has been described. In the second embodiment, a case where the X-ray image I1 and the X-ray image I2 are collected as a “transparent image” will be described. That is, in the second embodiment, the X-ray image I1 and the X-ray image I2 are collected as a "transparent image" using a low dose of X-rays as compared with the "photographed image" as in the fluoroscopic image I4. Will be described.

The X-ray diagnostic apparatus 100 according to the second embodiment has the same configuration as the X-ray diagnostic apparatus 100 according to the first embodiment shown in FIG. 1, and is one of the processes by the collection function 211 and the generation function 213. The parts are different. Therefore, the points having the same configurations as those described in the first embodiment are designated by the same reference numerals as those in FIG. 1, and the description thereof will be omitted.

Hereinafter, the perspective roadmap according to the second embodiment will be described with reference to FIG. 7. FIG. 7 is a diagram for explaining a perspective roadmap according to the second embodiment. First, as shown in FIG. 7, the collection function 211 according to the second embodiment is injected with an X-ray image I1 based on X-rays transmitted through the subject P before the contrast medium is injected, and the contrast medium is injected. An X-ray image I2 based on the X-ray transmitted through the subject P after being performed is collected.

Here, the collecting function 211 collects the X-ray image I1 and the X-ray image I2 by using, for example, the X-ray of the first dose. That is, the collection function 211 collects the entire surfaces of the X-ray image I1 and the X-ray image I2 under the same X-ray conditions as the region of interest R1 in the fluoroscopic image I4. Then, as shown in FIG. 7, the generation function 213 generates the blood vessel image I3 from which the background element such as the bone is removed by differentiating the X-ray image I1 and the X-ray image I2.

Further, as shown in FIG. 7, the generation function 213 according to the second embodiment uses the X-ray image I1 based on the X-ray transmitted through the subject P before the contrast medium is injected and the second dose. A wire mask image I5 is generated by using the X-ray image I52 based on the X-rays applied to the subject P. As an example, first, the acquisition function 212 acquires the position information of the region of interest R1 in the perspective image I4 based on the X-ray image I53. Next, the generation function 213 extracts a region corresponding to the region of interest R1 in the X-ray image I1 based on the position information of the region of interest R1. Further, the generation function 213 extracts a region corresponding to the region R2 other than the region of interest in the X-ray image I52 based on the position information of the region of interest R1. Then, the generation function 213 can generate the wire mask image I5 as shown in FIG. 7 by synthesizing the regions extracted from the X-ray image I1 and the X-ray image I52, respectively.

Then, as shown in FIG. 7, the generation function 213 generates a difference image I6 which is a difference between the perspective image I4 and the wire mask image I5. Further, as shown in FIG. 7, the generation function 213 generates a superimposed image I7 in which the blood vessel image I3 and the difference image I6 are superimposed, or a superimposed image I8 in which the background component of the subject P is superimposed on the superimposed image I7. Generate. Further, the display control function 214 causes the superimposed image I7 and the superimposed image I8 to be displayed on the display 23.

Next, an example of the processing procedure by the X-ray diagnostic apparatus 100 will be described with reference to FIG. FIG. 8 is a flowchart for explaining a series of processes of the X-ray diagnostic apparatus 100 according to the second embodiment. Step S202, step S204 and step S207 are steps corresponding to the collection function 211. Step S205 is a step corresponding to the acquisition function 212. Step S203, step S206, step S208 and step S209 are steps corresponding to the generation function 213. Step S210 is a step corresponding to the display control function 214.

First, the processing circuit 21 determines whether or not the inspection start command has been accepted (step S201), and if it does not accept the start command, it goes into a standby state (step S201 negative). On the other hand, when the start command is received (step S201 affirmative), the processing circuit 21 includes an X-ray image based on X-rays transmitted through the subject P before the contrast medium is injected and an X-ray image after the contrast medium is injected. An X-ray image based on the X-ray transmitted through the subject P is collected using the X-ray of the first dose (step S202). Further, the processing circuit 21 generates a blood vessel image by differentiating the X-ray images before and after the injection of the contrast medium (step S203).

Next, the processing circuit 21 irradiates the subject P with X-rays at a second dose and collects a second X-ray image (step S204). Further, the processing circuit 21 acquires the position information of the region of interest R1 from the X-ray images collected based on the X-rays irradiated with different doses to the region of interest R1 and the region R2 other than the region of interest (step). S205). Then, the processing circuit 21 generates a wire mask image based on the first X-ray image, the second X-ray image, and the position information of the region of interest R1 (step S206).

When the device insertion into the blood vessel is started, the processing circuit 21 controls the filter 13b to irradiate the region of interest R1 with X-rays at the first dose, and the region R2 other than the region of interest is the first. Irradiate X-rays at the dose of 2 and collect a third X-ray image over time (step S207). Next, the processing circuit 21 generates a difference image obtained by difference between each third X-ray image collected over time and the wire mask image over time (step S208). Then, the processing circuit 21 generates a superposed image in which the blood vessel image and the difference image are superimposed with time (step S209) and displays it on the display 23 (step S210).

Here, the processing circuit 21 determines whether or not the position of the region of interest R1 has been moved (step S211). When the position of the region of interest R1 is moved (affirmation in step S211), the processing circuit 21 shifts to step S205, acquires the position information of the region of interest R1 after the movement, and updates the wire mask image. On the other hand, when the position of the region of interest R1 is not moved (denial in step S211), the processing circuit 21 determines whether or not the inspection end command has been accepted (step S212), and if it does not accept the end command, it goes into a standby state. (Negation of step S212). On the other hand, when the end command is received (step S212 affirmative), the processing circuit 21 ends the processing.

As described above, according to the second embodiment, the collection function 211 includes an X-ray image I1 which is a fluoroscopic image based on X-rays transmitted through the subject P before the contrast medium is injected, and the contrast medium. An X-ray image I2, which is a fluoroscopic image based on X-rays transmitted through the subject P after being injected, is collected using a first dose of X-rays. In addition, the generation function 213 generates a wire mask image I5 using the X-ray image I1 based on the X-rays transmitted through the subject P before the contrast medium is injected as the first X-ray image. Therefore, the X-ray diagnostic apparatus 100 according to the second embodiment reduces the number of X-ray images collected to generate the wire mask image I5, reduces the exposure dose of the subject P, and reduces the exposure dose of the wire mask. The time required to collect images can be shortened.

By the way, although the first and second embodiments have been described so far, various different embodiments may be implemented in addition to the first and second embodiments described above.

In the above-described embodiment, the position information of the region R1 in the fluoroscopic image I4 is obtained from the X-ray image I53 collected based on the X-rays irradiated to the region R1 and the region R2 other than the region R2 at different doses. An example of acquiring is described. Here, the position information of the region of interest R1 in the perspective image I4 can be acquired by various methods. Hereinafter, an example of acquiring the position information of the region of interest R1 by the acquisition function 212 will be described.

First, an example of acquiring the position information of the region of interest R1 by the acquisition function 212 will be described with reference to FIG. FIG. 9 is a diagram for explaining a perspective roadmap according to the third embodiment. As shown in FIG. 9, the collection function 211 is based on X-rays irradiated with different doses to the region of interest R1 and the region R2 other than the region of interest when the medical device is inserted into the subject P. , X-ray image I54 is collected. Then, the acquisition function 212 can acquire the position information of the interest region R1 in the perspective image I4 from the difference in the pixel values between the interest region R1 and the region R2 in the X-ray image I54. That is, the acquisition function 212 can acquire the position information of the region of interest R1 even when the X-ray image I54 includes the medical device.

Further, the acquisition function 212 according to the third embodiment can also use the perspective image I4 as the X-ray image I54 shown in FIG. That is, the acquisition function 212 can acquire the position information of the region R1 of interest in the perspective image I4 based on the difference in pixel values between the region R1 of interest in the perspective image I4 and the region R2 other than the region of interest. As an example, the acquisition function 212 can acquire the position information of the region of interest R1 based on a predetermined image (for example, the first collected image) of the fluoroscopic images I4 generated over time. can. Further, to give an example, the acquisition function 212 can acquire the position information of the region of interest R1 over time by using each of the plurality of perspective images I4 generated over time.

Further, for example, the acquisition function 212 according to the third embodiment can acquire the position information of the region of interest R1 in the fluoroscopic image I4 based on the dose of X-rays to the subject P and the irradiation range. As an example, the acquisition function 212 obtains information on the opening degree of the diaphragm blade of the collimator 13a controlled by the processing circuit 21 and information on the positions of the X-ray tube 12, the collimator 13a, the top plate 14, and the subject P. It is used to calculate the X-ray irradiation range for the subject P. Further, the acquisition function 212 calculates the dose of X-rays irradiated to each position of the subject P by using the information on the position of the filter 13b controlled by the processing circuit 21. Then, the acquisition function 212 can acquire the position information of the region of interest R1 in the fluoroscopic image I4 based on the calculated X-ray dose and irradiation range. That is, the acquisition function 212 can acquire the position information of the region of interest R1 based on the distribution of the X-ray dose to the subject P.

Further, for example, the acquisition function 212 can acquire the position information of the region of interest R1 based on the position of the opening of the filter 13b or the second region.
As an example, the acquisition function 212 is an intersection of an X-ray focal point in the X-ray tube 12 and a plurality of straight lines passing through the opening of the filter 13b or the edge of the second region and the detection surface in the X-ray detector 16. By specifying the set of the above as the contour of the region of interest R1, the position information of the region of interest R1 can be acquired.

When the virtual collimator can be used for collecting the fluoroscopic image I4, the acquisition function 212 can acquire the position information of the region R1 of interest in the fluoroscopic image I4 from the information of the virtual collimator. Here, the virtual collimator is a function of displaying the position of the collimator 13a on a LIH (Last Image Hold) image collected by fluoroscopy and supporting the setting of the X-ray irradiation range.

In addition, the generation function 213 can generate the wire mask image I5 based on various combinations of X-ray images. Here, an example of generating the wire mask image I5 will be described with reference to FIG. FIG. 10 is a diagram for explaining a perspective roadmap according to a third embodiment. For example, as shown in FIG. 10, the generation function 213 includes an X-ray image I1 which is a fluoroscopic image based on X-rays transmitted through the subject P before the contrast medium is injected, and the subject P at a second dose. A wire mask image I5 can be generated by using the X-ray image I52 based on the X-rays irradiated to the subject P and the X-ray image I54 collected with the medical device inserted in the subject P.

In the above-described embodiment, the case where the superimposed image I7 in which the blood vessel and the medical device are displayed or the superimposed image I8 in which the peripheral tissue is displayed in addition to the blood vessel and the medical device is displayed on the display 23 has been described. The form is not limited to this. For example, the display control function 214 can display the difference image I6 on which the medical device is displayed on the display 23.

Further, in the above-described embodiment, the case where the wire mask image I5 is generated and the differential image I6 is generated by differentiating the perspective image I4 and the wire mask image I5 has been described, but the embodiment is limited to this. It's not a thing. For example, the wire mask image I5 may not be generated by synthesizing the region corresponding to the region of interest R1 in the X-ray image I51 and the region corresponding to the region R2 other than the region of interest in the X-ray image I52. You may. That is, the wire mask image I5 is an example for generating the difference image I6. Therefore, without generating the wire mask image I5, the region R1 in the perspective image I4 and the region corresponding to the region R1 in the X-ray image I51 are simply differentiated, and the region R2 in the perspective image I4 and the X-ray image I52 The difference image I6 may be generated by differentiating from the region corresponding to the region R2 in.

Further, in the above-described embodiment, the first X-ray image I51 is collected using the first dose X-ray, and the second X-ray image I52 is collected using the second dose X-ray. The case where the fluoroscopic image I4 is collected using the X-rays of the first dose and the second dose has been described. However, the embodiment is not limited to this. For example, when the first X-ray image I51 is collected using the first dose of X-rays, the dose of the X-rays applied to the region of interest R1 of the fluoroscopic image I4 is different from the first dose. There may be. Further, for example, when the second X-ray image I52 is collected using the X-ray of the second dose, the dose of the X-ray irradiated to the region R2 other than the region of interest of the fluoroscopic image I4 is the second dose. The dose may be different from the dose. In other words, the fluoroscopic image I4 may be an X-ray image collected based on X-rays irradiated to the region R1 and the region R2 at different doses.

Hereinafter, the case where the fluoroscopic image I4 is not an X-ray image collected based on the X-rays irradiated with the first dose and the second dose to the region R1 and the region R2, respectively, will be described. In the following, as an example, the first X-ray image I51 is collected using the first dose X-ray, the second X-ray image I52 is collected using the second dose X-ray, and the region of interest is collected. A case where a fluoroscopic image I4 is collected based on X-rays irradiated with a third dose and a fourth dose to R1 and region R2, respectively, will be described. The third dose is different from the first dose. Further, the fourth dose is different from the second dose and is lower than the third dose.

First, the collection function 211 includes an X-ray image I51 based on the X-rays irradiated on the subject P at the first dose and an X-ray image I52 based on the X-rays irradiated on the subject P at the second dose. To collect. Next, the collection function 211 collects the fluoroscopic image I4 based on the X-rays irradiated to the subject P at the third dose and the fourth dose over time. Next, the acquisition function 212 acquires the position information of the region of interest R1 in the perspective image I4. Then, the generation function 213 performs a difference between the X-ray image I51 and the X-ray image I52 and the fluoroscopic image I4 based on the position information of the region R1 of interest, and generates the difference image I6.

Here, since the first dose and the third dose are different doses, the brightness is different between the X-ray image I51 and the region of interest R1 in the fluoroscopic image I4. Therefore, even if the region of interest R1 in the fluoroscopic image I4 and the region corresponding to the region of interest R1 in the X-ray image I51 are different, the background components such as bones may not be differently removed. Similarly, even if the region R2 other than the region of interest in the fluoroscopic image I4 and the region corresponding to the region R2 in the X-ray image I52 are different, the background component such as bone may not be differentially removed.

Therefore, the generation function 213 adjusts the gains of the X-ray image I51 and the X-ray image I52 prior to the difference between the fluoroscopic image I4 and the X-ray image I51 and the X-ray image I52. Specifically, the generation function 213 includes the average value of the pixel values of each pixel in the region of interest R1 in the perspective image I4 and the average value of the pixel values of each pixel in the region corresponding to the region of interest R1 in the X-ray image I51. The pixel value of each pixel in the region corresponding to the region of interest R1 in the X-ray image I51 is increased or decreased at a constant rate so that Here, the generation function 213 increases or decreases the pixel value of each pixel in the region corresponding to the region R2 in the X-ray image I51 at the same rate as increasing or decreasing the pixel value of each pixel in the region corresponding to the region R1 of interest. It may be the case to make it. Further, when the medical device is included in the region of interest R1 in the perspective image I4, the generation function 213 corresponds to the medical device in the region of interest R1 as the average value of the pixel values of each pixel of the region of interest R1. The average value of the pixel values of each pixel excluding the pixels may be used.

Further, the generation function 213 makes the average value of the pixel values of each pixel of the region R2 in the perspective image I4 the same as the average value of the pixel values of each pixel of the region corresponding to the region R2 in the X-ray image I52. In addition, the pixel value of each pixel in the region corresponding to the region of interest R2 in the X-ray image I52 is increased or decreased at a constant rate. Here, the generation function 213 increases or decreases the pixel value of each pixel in the region corresponding to the region R2 in the X-ray image I52 at the same rate as increasing or decreasing the pixel value of each pixel in the region corresponding to the region R2. It may be the case to make it. Further, when the region R2 in the fluoroscopic image I4 includes the medical device, the generation function 213 excludes the pixels corresponding to the medical device in the region R2 as the average value of the pixel values of each pixel in the region R2. The average value of the pixel values of each pixel may be used.

Then, the generation function 213 differs the region of interest R1 in the perspective image I4 from the region corresponding to the region of interest R1 in the X-ray image I51 after adjusting the pixel value, and the region R2 other than the region of interest in the perspective image I4. And the region corresponding to the region R2 in the X-ray image I52 after adjusting the pixel values are differentiated to generate the differential image I6.

In the above-described embodiment, the X-ray image I51 based on the X-rays irradiated to the subject P at the first dose and the X-ray image I52 based on the X-rays irradiated to the subject P at the second dose are obtained. The case where the X-ray image I51 and the X-ray image I52 and the fluoroscopic image I4 are different from each other to generate the difference image I6 has been described. That is, in the above-described embodiment, the case where at least two X-ray images used for the difference from the fluoroscopic image I4 are collected has been described. However, the embodiment is not limited to this. Hereinafter, a case where only one X-ray image used for the difference from the fluoroscopic image I4 is collected will be described.

First, the collection function 211 collects an X-ray image (hereinafter referred to as an X-ray image I9) based on the X-rays applied to the subject P. Here, the collection function 211 can collect the X-ray image I9 using X-rays of an arbitrary dose. In the following, as an example, a case where the collection function 211 collects the X-ray image I9 using the X-ray of the first dose will be described.

Next, the collection function 211 collects the fluoroscopic image I4 over time based on the X-rays irradiated to the region R1 and the region R2 at different doses. Here, the collection function 211 can collect the fluoroscopic image I4 by using X-rays of an arbitrary dose. In the following, as an example, a case where the collection function 211 collects the fluoroscopic image I4 based on the X-rays irradiated to the region R1 and the region R2 at the third dose and the fourth dose, respectively, will be described. ..

Next, the generation function 213 generates an X-ray image used for the difference from the fluoroscopic image I4 from the X-ray image I9 based on the position information of the region of interest R1 acquired by the acquisition function 212.

For example, the generation function 213 uses the X-ray image I9 as an X-ray image used for the difference from the perspective image I4, the X-ray image I10 according to the brightness of the region of interest R1 in the perspective image I4, and the region in the perspective image I4. An X-ray image I11 corresponding to the brightness of R2 is generated.

As an example, the generation function 213 first determines the average value of the pixel values of each pixel included in the region of interest R1 (hereinafter, referred to as the average value A1) based on the position information of the region of interest R1 in the perspective image I4. And the average value of the pixel values of each pixel included in the area R2 (hereinafter, referred to as the average value A2) are acquired. Next, the generation function 213 acquires the average value of the pixel values of each pixel included in the region corresponding to the region of interest R1 in the X-ray image I9 (hereinafter, referred to as the average value A3), and averages the average value A3 with respect to the average value A3. By calculating the ratio of the value A1 and multiplying the calculated ratio by the pixel value of each pixel of the X-ray image I9, the X-ray image I10 corresponding to the brightness of the region of interest R1 in the perspective image I4 is generated. Further, the generation function 213 acquires the average value of the pixel values of each pixel included in the region corresponding to the region R2 in the X-ray image I9 (hereinafter, referred to as the average value A4), and the average value A2 with respect to the average value A4. By calculating the ratio of and multiplying the calculated ratio by the pixel value of each pixel of the X-ray image I9, the X-ray image I11 corresponding to the brightness of the region R2 in the perspective image I4 is generated. Then, the generation function 213 differs the region of interest R1 in the perspective image I4 from the region corresponding to the region of interest R1 in the X-ray image I10, and corresponds to the region R2 in the perspective image I4 and the region R2 in the X-ray image I11. The difference image I6 is generated by differentiating from the area to be processed. In such a case, the X-ray image I9 is described as the first X-ray image, the X-ray image I10 is described as the second X-ray image, and the X-ray image I11 is described as the third X-ray image. , The perspective image I4 is referred to as a fourth X-ray image.

Further, for example, the generation function 213 uses the X-ray image I9 as an X-ray image used for the difference from the perspective image I4, which is an X-ray image according to the brightness of the region R1 of interest and the brightness of the region R2 in the perspective image I4. Generate I12.

As an example, the generation function 213 first has an average value A1 of the pixel values of each pixel included in the region R1 and each pixel included in the region R2 based on the position information of the region R1 of interest in the perspective image I4. The average value A2 of the pixel values of Further, the generation function 213 includes an average value A3 of the pixel values of each pixel included in the region corresponding to the region of interest R1 in the X-ray image I9 and each pixel included in the region corresponding to the region R2 in the X-ray image I9. The average value A4 of the pixel values is acquired. Then, the generation function 213 multiplies the ratio of the average value A1 to the average value A3 by the pixel value of each pixel included in the region of interest R1 of the X-ray image I9, and multiplies the ratio of the average value A2 to the average value A4 by the X-ray image I9. By multiplying the pixel value of each pixel included in the region R2 of, an X-ray image I12 corresponding to the brightness of the region R1 of interest and the brightness of the region R2 is generated. Then, the generation function 213 differentiates the X-ray image I12 and the fluoroscopic image I4 to generate the difference image I6. In such a case, the X-ray image I9 is described as a first X-ray image, the X-ray image I12 is described as a second X-ray image, and the fluoroscopic image I4 is described as a third X-ray image.

Further, in the above-described embodiment, the fluoroscopic image I4 collected by using X-rays of two types of doses, the first dose and the second dose, has been described, but the embodiment is not limited thereto. .. For example, a fluoroscopic image I4 may be collected using three or more doses of X-rays. In such a case, the collection function 211 collects, for example, X-ray images obtained by irradiating the entire surface with X-rays at each dose in the fluoroscopic image I4. Further, the acquisition function 212 acquires the dose distribution in the fluoroscopic image I4. Further, the generation function 213 generates a wire mask image I5 based on the X-ray image collected at each dose and the distribution in the fluoroscopic image I4 of each dose. Then, the generation function 213 generates a difference image obtained by differentiating the fluoroscopic image I4 and the wire mask image I5 collected by using X-rays of three or more kinds of doses, and the display control function 214 executes the fluoroscopic roadmap. can do.

Each component of each device according to the above-described embodiment is a functional concept, and does not necessarily have to be physically configured as shown in the figure. That is, the specific form of distribution / integration of each device is not limited to the one shown in the figure, and all or part of the device is functionally or physically dispersed / physically distributed in arbitrary units according to various loads and usage conditions. It can be integrated and configured. Further, each processing function performed by each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

Further, the image processing method described in the above-described embodiment can be realized by executing an image processing program prepared in advance on a computer such as a personal computer or a workstation. This image processing program can be distributed via a network such as the Internet. Further, this image processing program can also be executed by being recorded on a computer-readable recording medium such as a hard disk, flexible disk (FD), CD-ROM, MO, or DVD, and being read from the recording medium by the computer. ..

According to at least one embodiment described above, the efficiency of interventional treatment can be improved.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, as well as in the scope of the invention described in the claims and the equivalent scope thereof.

100 X-ray diagnostic device 211 Collection function 212 Acquisition function 213 Generation function 214 Display control function 215 Filter control function

Claims (13)

A first collection unit that collects a first X-ray image based on the X-rays applied to the subject at the first dose, and
A second collecting unit that collects a second X-ray image based on the X-rays applied to the subject at a second dose lower than the first dose.
Based wherein the medical device is inserted into the X-rays emitted by the second dose to the first X-ray a region other than the region of interest is irradiated with a dose to the subject area of interest And the third collection unit that collects the third X-ray image,
An acquisition unit that acquires the position information of the region of interest in the third X-ray image, and
Based on the position information, the positions corresponding to the regions of interest in the first X-ray image and the second X-ray image are acquired, respectively, and the regions of interest and the first in the third X-ray image are obtained. The region corresponding to the region of interest in the X-ray image is different from the region corresponding to the region of interest in the third X-ray image and the region corresponding to the region other than the region of interest in the second X-ray image. A generator that generates a difference image that is the difference between
X-ray diagnostic device equipped with. The X according to claim 1, wherein the acquisition unit acquires the position information from X-ray images collected based on X-rays irradiated to the region of interest and a region other than the region of interest at different doses. Line diagnostic device. The X-ray diagnostic apparatus according to claim 2, wherein the acquisition unit acquires the position information from the third X-ray image. The X-ray diagnostic apparatus according to claim 1, wherein the acquisition unit acquires the position information based on the distribution of the X-ray dose to the subject. A filter that attenuates X-rays, the first region that attenuates the transmitted X-rays, and the aperture for passing the X-rays without attenuation or the attenuation lower than the X-rays that pass through the first region. A filter having a second region for attenuating X-rays transmitted at a rate and allowing the first region to move with the movement of the opening or the second region.
A filter control unit that controls the movement of the opening or the second region is further provided.
The third collector is after the X-ray tube is emitted such that the opening or the second region corresponds to the region of interest and the first region corresponds to a region other than the region of interest. Based on X-rays radiated to the region of interest through the opening or the second region and X-rays emitted from the X-ray tube and then radiated to regions other than the region of interest through the first region. The X-ray diagnostic apparatus according to claim 1, wherein the third X-ray image is collected. The X-ray diagnostic apparatus according to claim 5, wherein the acquisition unit acquires the position information based on the position of the opening or the second region of the filter. A display control unit that displays an X-ray image on the display unit,
A blood vessel image that is a difference between an X-ray image based on the X-ray transmitted through the subject before the contrast medium is injected and an X-ray image based on the X-ray transmitted through the subject after the contrast medium is injected. Further equipped with a blood vessel image collection unit to collect
The generation unit generates a superposed image in which the difference image and the blood vessel image are superimposed.
The X-ray diagnostic apparatus according to any one of claims 1 to 6, wherein the display control unit displays the superimposed image on the display unit. A display control unit that displays an X-ray image on the display unit,
A blood vessel image that is a difference between an X-ray image based on the X-ray transmitted through the subject before the contrast medium is injected and an X-ray image based on the X-ray transmitted through the subject after the contrast medium is injected. Further equipped with a blood vessel image collection unit to collect
The generation unit generates a superposed image in which an X-ray image based on the X-ray transmitted through the subject, the difference image, and the blood vessel image are superimposed.
The X-ray diagnostic apparatus according to any one of claims 1 to 6, wherein the display control unit displays the superimposed image on the display unit. The blood vessel image collecting unit includes a fluoroscopic image based on X-rays transmitted through the subject before the contrast medium is injected, and a fluoroscopic image based on the X-rays transmitted through the subject after the contrast medium is injected. Collect the blood vessel images that are different from each other,
7. X-ray diagnostic equipment. A first collection unit that collects a first X-ray image based on the X-rays applied to the subject, and
A generation unit that generates a second X-ray image and a third X-ray image from the first X-ray image, and a generation unit.
For the region of interest of the subject into which the medical device is inserted and the region other than the region of interest, the dose of X-rays irradiated to the region of interest is the X-rays irradiated to the region other than the region of interest. A second collector that collects a fourth X-ray image based on the X-rays that are irradiated so that they have a higher relationship than the dose.
A acquisition unit for acquiring the position information of the region of interest in the fourth X-ray image is provided.
The generation unit generates the second X-ray image according to the brightness of the region of interest in the fourth X-ray image based on the position information, and the generation unit generates the second X-ray image in accordance with the brightness of the region of interest in the fourth X-ray image. The third X-ray image is generated according to the brightness of the region other than the region, and further, the region corresponding to the region of interest in the fourth X-ray image and the region of interest in the second X-ray image. X-rays to generate a difference image in which the region other than the region of interest in the fourth X-ray image and the region corresponding to the region other than the region of interest in the third X-ray image are different. Diagnostic device. A first collection unit that collects a first X-ray image based on the X-rays applied to the subject, and
A generation unit that generates a second X-ray image from the first X-ray image, and
For the region of interest of the subject into which the medical device is inserted and the region other than the region of interest, the dose of X-rays irradiated to the region of interest is the X-rays irradiated to the region other than the region of interest. A second collector that collects a third X-ray image based on the X-rays that are irradiated so that they have a higher relationship than the dose.
A acquisition unit for acquiring the position information of the region of interest in the third X-ray image is provided.
Based on the position information, the generation unit adjusts the brightness of the region corresponding to the region of interest in the first X-ray image according to the brightness of the region of interest in the third X-ray image. By adjusting the brightness of the region corresponding to the region other than the region of interest in the first X-ray image according to the brightness of the region other than the region of interest in the third X-ray image, the first An X-ray diagnostic apparatus that generates 2 X-ray images and further generates a difference image obtained by differentiating the 2nd X-ray image and the 3rd X-ray image. A first x-ray image is collected based on the x-rays applied to the subject at the first dose.
A second X-ray image is collected based on the X-rays applied to the subject at a second dose lower than the first dose.
Based wherein the medical device is inserted into the X-rays emitted by the second dose to the first X-ray a region other than the region of interest is irradiated with a dose to the subject area of interest And collect a third X-ray image
The position information of the region of interest in the third X-ray image is acquired, and the position information is obtained.
Based on the position information, the positions corresponding to the regions of interest in the first X-ray image and the second X-ray image are acquired, respectively, and the regions of interest and the first in the third X-ray image are obtained. The region corresponding to the region of interest in the X-ray image is different from the region corresponding to the region of interest in the third X-ray image, and the region corresponding to the region other than the region of interest in the second X-ray image. An image processing program that causes a computer to execute each process that generates a difference image that is the difference between. A first collection unit that collects a first X-ray image based on the X-rays applied to the subject at the first dose, and
A second collecting unit that collects a second X-ray image based on the X-rays applied to the subject at a second dose lower than the first dose.
For the region of interest of the subject into which the medical device is inserted and the region other than the region of interest, the dose of X-rays irradiated to the region of interest is the X-rays irradiated to the region other than the region of interest. A third collection unit that collects a third X-ray image based on the X-rays that are irradiated so that they have a higher relationship than the dose.
An acquisition unit that acquires the position information of the region of interest in the third X-ray image, and
Based on the position information, the positions corresponding to the regions of interest in the first X-ray image and the second X-ray image are acquired, respectively, and the regions of interest and the interest in the third X-ray image are obtained. The region corresponding to the region of interest in the first X-ray image whose brightness is adjusted according to the brightness of the region is differentiated from the region other than the region of interest in the third X-ray image and the region of interest. A generation unit that generates a difference image obtained by differentiating a region corresponding to a region other than the region of interest in the second X-ray image whose brightness is adjusted according to the brightness of the region other than the region.
X-ray diagnostic device equipped with.

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