JP2019098057A - Radiation therapy equipment - Google Patents

Abstract

To provide radiation therapy equipment capable of coping with deformation of a subject in therapy time, in bed positioning using a transparent image in radiation therapy.SOLUTION: The radiation therapy equipment comprises: an X-ray imaging device for imaging a subject 130 by an X-ray for generating a transparent image; a setting part 421 for setting a positioning reference region 520 on a therapy plan CT image which is imaged in creation time of a therapy plan; a deformation part 422 for generating a deformed CT image in which a region other than the reference region 520 in the therapy plan CT image is deformed; a projection part 423 for projecting the deformed CT image in a manner of imitating a scheme of the X-ray imaging device for generating a projection image; and an evaluation part 424 for evaluating a match degree of the projection image and the X-ray fluoroscopic image imaged by the X-ray imaging device.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a radiotherapy apparatus for treating a diseased part such as a tumor by irradiating radiation such as charged particles and X-rays.

  In Patent Document 1, “an image processing unit and a display unit are provided, and the image processing unit generates a treatment plan image generated in advance as a tomographic image and a target and / or a dangerous organ generated by the treatment planning apparatus. The information of the region of interest including is input, the positioning image for positioning for irradiating radiation, which is imaged by the tomographic imaging device, is input, the treatment plan image and the positioning image are aligned, and aligned. The first and second deformation parameters representing the deformation of the whole image and the deformation of the partial image between the treatment plan image and the positioning image are calculated, and the movement of the region of interest in the treatment plan image and the region of interest in the positioning image Calculating a displacement parameter representing H. The position parameter representing displacement and rotation of the bed is calculated based on the first and second deformation parameters and the displacement parameter, and the first deformation is calculated. One or more of an image representing a parameter, an image representing a second deformation parameter, an image representing a movement amount parameter, and an image representing a positioning parameter are displayed on the display unit, and the positioning parameter is displayed to move and rotate the bed. An "output" radiation therapy device is shown.

JP, 2015-83068, A

  In radiation therapy, X-ray fluoroscopic imaging of the subject on the bed at the time of treatment and comparison of the imaged image with the reference image of the treatment plan locates the bed so that the subject position matches the plan.

  In particle beam therapy, X-ray IMRT (Intensity Modulated Radiation Therapy), etc., it is necessary to make the target position coincide with the plan with high accuracy even in positioning because a dose distribution concentrated on the target can be realized.

  As described above, in order to position the target position with high accuracy, it is required to calculate the deviation at the time of planning and treatment for a total of six degrees of freedom, ie, three degrees of parallel movement and three degrees of rotation of the object. Moreover, in order to shorten the treatment time, a calculation method with a short calculation time is required.

  Here, a treatment plan is performed on a three-dimensional image captured in advance before treatment. Typically, an X-ray CT image composed of a plurality of slices is used for this three-dimensional image, and in the treatment plan, the positional relationship with respect to the subject and the radiation irradiation apparatus reflected in the three-dimensional image is planned.

  The positional relationship between the subject position and the radiation irradiating apparatus at the time of treatment is confirmed by an X-ray fluoroscopic image of the subject imaged by the X-ray imaging apparatus whose positional relationship is known with the radiation irradiating apparatus. The fluoroscopic image is used for positioning based on the internal structure of the subject. The fluoroscopic images are captured by two different imaging devices from two orthogonal directions.

  By determining from the image the positional relationship between the subject in the treatment plan three-dimensional image and the subject in the X-ray fluoroscopic image, the amount of deviation from the plan of the position relationship between the radiation irradiation apparatus at the time of treatment and the subject It is possible to detect

  In comparison between a treatment plan three-dimensional image and a fluoroscopic image, DRR (Digitally Reconstracted) numerically generates an X-ray fluoroscopic image by simulation based on the positional relationship with the radiotherapy device planned from the treatment plan three-dimensional image Radiograph) is generated and compared with fluoroscopic images at the time of treatment.

  If the subject completely has the same shape as the treatment plan at the time of comparison, by adjusting the position of the bed, a state in which the DRR and the fluoroscopic image completely coincide with each other can be obtained. However, since the subject can usually deform, it is rare for the entire image to match, which is very difficult.

  In bed positioning, there is a technique as described in the above-mentioned Patent Document 1 as a method which enables alignment calculation even if there is deformation of the subject. This technique makes it possible to position the bed corresponding to the deformation of the object using a tomographic image.

  However, the technology described in Patent Document 1 described above is to compare a three-dimensional image captured by a tomographic imaging apparatus with a treatment plan image. Here, when a three-dimensional image is acquired at the time of treatment such as immediately before treatment or during radiation irradiation (during treatment), it takes time for imaging, so in order to shorten the treatment time, instead of the technology described in Patent Document 1, Technology is required to cope with the deformation of

  The present invention provides a radiation treatment apparatus capable of coping with deformation of a subject at the time of treatment in bed positioning using a fluoroscopic image in radiation treatment.

  The present invention includes a plurality of means for solving the above problems, and an example thereof is a radiotherapy apparatus which irradiates radiation to a target area, and the positioning operation of an object having the target area The positioning reference area is set on the bed on which the subject can be placed, the fluoroscopic unit that images the subject with X-rays to generate a fluoroscopic image, and the treatment plan CT image captured at the time of creating the treatment plan And generate a deformed image by deforming other than the reference area of the treatment plan CT image, and projecting the deformed image to simulate the system of the see-through portion to generate a projected image, and the projected image and the see-through And an arithmetic unit for evaluating the degree of coincidence with the X-ray fluoroscopic image picked up by the unit.

  According to the present invention, in bed positioning using a fluoroscopic image in radiation therapy, it is possible to cope with deformation of a subject at the time of treatment.

It is a figure which shows the system outline | summary of the radiotherapy apparatus of Example 1 of this invention. FIG. 7 is a view showing an example of a display screen of the display device of the radiation therapy apparatus of the first embodiment. FIG. 8 is a diagram showing a calculation processing flow of a bed movement amount in the radiation treatment apparatus of the first embodiment. FIG. 6 is a view for explaining an outline of image deformation in the radiation treatment apparatus of the first embodiment. It is a figure explaining an example of the pattern of the image deformation in the radiotherapy apparatus of Example 2 of this invention. It is a figure which shows an example of the screen which designates the image deformation in the radiotherapy apparatus of Example 3 of this invention. It is a figure which shows the mode of the machine learning of the deformation pattern in the radiotherapy apparatus of Example 4 of this invention. FIG. 18 is a view showing how a deformation pattern is selected using the learning result in the radiation treatment apparatus of the fourth embodiment. It is a figure which shows an example of the warning screen in the radiotherapy apparatus of Example 5 of this invention.

  Hereinafter, an embodiment of the radiation treatment apparatus of the present invention will be described with reference to the drawings.

Example 1
A first embodiment of a radiotherapy apparatus of the present invention will be described with reference to FIGS. 1 to 4. First, an overview of the overall configuration of a radiation treatment apparatus will be described using FIGS. 1 and 2. FIG. 1 is a view showing a system outline of the radiation treatment apparatus of the first embodiment. FIG. 2 is a view showing an example of a display screen in the display device.

  As shown in FIG. 1, the radiation treatment apparatus 1 is an apparatus for applying a treatment radiation from a treatment radiation irradiating apparatus 100 to a target area in a subject 130 on a bed 120.

  The therapeutic radiation irradiation apparatus 100 is, for example, a proton beam irradiation apparatus that irradiates protons to a target area, and as shown in FIG. 1, a proton beam generator 101, a beam transport system 102 that transports a proton beam, an irradiation nozzle 103, Etc.

  In addition, although the treatment radiation irradiation apparatus 100 demonstrated the proton beam irradiation apparatus to the example, the treatment radiation irradiation apparatus 100 of this invention irradiates with particle beams other than proton beams, such as a carbon beam, X-rays, an electron beam, etc. It can be an apparatus. For example, in the case of using X-rays, the radiation irradiation apparatus comprises an X-ray generator, a beam transport system, and an irradiation nozzle.

  The general control device 10 is connected to the treatment radiation irradiation device 100, the X-ray imaging device, the bed 120, the image server 310, the display device 500, etc., and the radiation of the treatment radiation irradiation device 100, the X-ray imaging device, the bed 120 etc. The operation of each device in the treatment apparatus 1 is controlled. The general control device 10 includes a positioning calculation device 400, an X-ray fluoroscopic image imaging control device 240, a treatment control device 900, and the like.

  The bed 120 on which the subject 130 having the target area is placed can move in directions of three orthogonal axes on the basis of an instruction from the treatment control device 900 in the general control device 10, and further rotates around each axis. be able to. By these movements and rotations, the position of the subject 130 can be moved to a desired position.

  The three-dimensional imaging apparatus 300 captures a CT image of the subject 130 during treatment planning. The captured image is stored in the image server 310.

  The X-ray imaging apparatus for imaging a subject 130 with X-rays at the time of treatment to generate a fluoroscopic image is configured to image the subject 130 from two directions.

  Specifically, the X-ray imaging apparatus comprises an X-ray tube 200 for acquiring an X-ray fluoroscopic image of a target area in the object 130 and a first imaging apparatus including the detector 210 from different directions from the first imaging apparatus A second imaging device including an X-ray tube 220 for acquiring an X-ray fluoroscopic image of a target region in the subject 130 and a detector 230, and an X-ray fluoroscopic image imaging control device 240 for controlling the operation of each of these devices. ing.

  The first imaging device and the second imaging device are installed such that the paths of the respective X-rays intersect. The first imaging device and the second imaging device are preferably installed in directions orthogonal to each other, but may not be orthogonal.

  The X-ray imaging apparatus is an apparatus configured to sequentially capture an X-ray fluoroscopic image by rotating an imaging apparatus including an X-ray tube for acquiring an X-ray fluoroscopic image of a target region in the object 130 and a detector. be able to. Furthermore, the present invention is not limited to the case of acquiring X-ray fluoroscopic images from a plurality of or a plurality of directions, and it is also possible to perform imaging from one direction by one imaging device.

  The positioning calculation device 400 includes a communication unit 410, a computing unit 420, and a memory 430, and it is among the three-dimensional treatment plan CT image captured at the time of preparation of the treatment plan and the two-dimensional fluoroscopic image captured at the time of treatment. It is an apparatus which performs alignment arithmetic processing of the drawn target area.

  The communication unit 410 manages transmission and reception of data with the image server 310, the X-ray fluoroscopic image imaging control device 240, the treatment control device 900, and the like.

  The memory 430 stores data transmitted and received by the communication unit 410. For example, data such as a treatment plan CT image, a fluoroscopic image acquired by an X-ray imaging apparatus in two directions at the time of treatment to confirm the arrangement of the internal structure of the subject 130, and various images calculated by the calculator 420 described later Remember.

  The computing unit 420 includes a setting unit 421, a deformation unit 422, a projection unit 423, an evaluation unit 424, and a positioning unit 425.

  The setting unit 421 sets the positioning reference area 520 on the treatment plan CT image captured at the time of preparation of the treatment plan. It is desirable that this positioning reference area 520 be an area such as bone where deformation does not normally occur.

  The setting of the reference area 520 is not limited to the case where the operator inputs using the input device 600 as described later, and the setting unit 421 may analyze the treatment plan CT image and automatically set it.

  When the reference area 520 is set, the deformation unit 422 generates a deformed CT image in which an image other than the reference area 520 in the treatment plan CT image is deformed while the designated reference area 520 is fixed.

  The projection unit 423 numerically generates an X-ray fluoroscopic image acquired in an X-ray imaging system that simulates the system of the first imaging device with respect to the deformed CT image generated earlier by performing a DRR (hereinafter referred to as a projection image To generate). Further, a projection image acquired in an X-ray imaging system simulating the system of the second imaging device is generated with respect to the deformed CT image generated earlier. The generated projection image is stored in the memory 430. At this time, it is desirable to store the amount of deformation when generating a deformed CT image in the memory 430.

  The evaluation unit 424 compares and displays the plurality of projection images stored in the memory 430 and the X-ray fluoroscopic image acquired by the X-ray imaging device on the display screen 510 of the display device 500 (FIG. 4 and the like). Furthermore, image similarity such as normalized correlation coefficient is calculated and displayed as an index for comparing the coincidence of these images. The operator can compare the degree of coincidence between the plurality of projection images and the X-ray fluoroscopic image by referring to this display screen.

  The positioning unit 425 calculates the movement amount of the bed 120 as the positioning calculation of the bed 120 from the difference between the selected appropriate projection image and the fluoroscopic image when the appropriate projection image is selected by the operator.

  The display device 500 is a device for displaying various images such as a treatment plan CT image, a deformed CT image, a projection image and the like captured at the time of preparation of a treatment plan as a display screen 510 as shown in FIG. It consists of

  When the operator designates a reference area 520 as a positioning reference using the input device 600 with respect to the CT image 515 displayed on the display screen 510, the setting unit 421 of the computing unit 420 sets the CT image 515 to the reference area. Set 520.

  The input device 600 is a device for specifying the positioning reference area 520 to be set in the setting unit 421 of the positioning calculation device 400.

  Hereinafter, the flow of processing of positioning of the bed 120 in the radiotherapy apparatus 1 of the present embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram showing a process flow of calculating the bed movement amount. FIG. 4 is a diagram for explaining an outline of image deformation.

  The positioning calculation device 400 acquires the data of the treatment plan CT image of the subject 130 captured by the three-dimensional imaging device 300 in advance and stored in the image server 310 through the communication unit 410 according to the instruction of the operator through the communication unit 410. (Step S100).

  Next, during treatment, an X-ray fluoroscopic image of the subject 130 placed on the bed 120 is taken (Step SS150). A fluoroscopic image is captured by two devices, a first imaging device and a second imaging device. The captured image is sent from the X-ray imaging control unit to the positioning calculation unit 400, which is received by the communication unit 410 and stored in the memory 430 via the computing unit 420.

  Next, the operator operates the input device 600 on the CT image 515 displayed on the display screen 510 of the display device 500 to set a reference area 520 (step S200). Usually, by inputting a two-dimensional area on a plurality of slice planes of a CT image, a three-dimensional area obtained by connecting them is specified.

  Next, when the operator presses the calculation start button 530 on the display screen 510, the computing unit 420 of the positioning calculation device 400 starts the calculation (step S300).

  Next, the treatment plan CT image stored in the memory 430 on the positioning calculation device 400 is deformed by the calculator 420 to generate a deformed CT image (step S400). In the deformation of the CT image, the reference area 520 is fixed and the area outside it is deformed.

  Basically, as shown in FIG. 4, the deformation in step S400 sets the control points 540 three-dimensionally in a three-dimensional grid shape, and shifts the control points 540 from the original position. Control. Each pixel in the inner area of the control point 540 is shifted based on the shift amount obtained by interpolating the shift amount of the surrounding control point 540. The movement pattern of the control point 540 may be deformed by a plurality of predetermined patterns, or the operator may select a pattern.

  The transition pattern changes based on the reference area 520 set in step S200. First, when the control point 540 that constitutes the vertex of the grid is included inside the reference area 520, the grid-like control point 540 is not displaced. As a result, the base state is maintained without deformation of the reference area 520.

  Among deformation patterns, for deformation such as rotation and distortion, by setting the rotation center and the origin of distortion to the reference area 520, the rotation / distortion around the reference area 520 is small, and the rotation distortion becomes larger as it gets farther Let's do it. Although the specific processing of the deformation has been described in detail here, the image may be distorted by other methods.

  Next, a numerically deformed deformed CT image is projected in a system simulating the X-ray imaging apparatus (step S500). When there are a plurality of imaging devices, images are projected in a plurality of directions. Alternatively, when the X-ray imaging apparatus is rotated and imaging is performed a plurality of times, the deformed CT image is projected for each imaging planned angle. The projection image is projected in a state in which the organs in the object 130 overlap, and each organ is displaced according to the set deformation pattern, but the structure in the reference area 520 is projected without distortion.

  Next, the projection image generated in step S500 and the X-ray fluoroscopic image are aligned (step S550). The operator moves one of the projection image and the X-ray fluoroscopic image displayed superimposed on the screen, and visually searches for a matching position. At this time, the matching degree of each image obtained by the evaluating unit 424 is displayed together.

  The present step S550 is not limited to the case where it is performed by the operator's operation and selection, and the evaluation unit 424 can perform automatic alignment using an algorithm. As a method of this algorithm, there is a method of moving an image by an optimization algorithm and searching for a position that maximizes image similarity such as a normalized correlation coefficient.

  The positioning calculation device 400 executes the steps S400 to S550 for all the determined patterns (step S600).

  Next, among all the calculated patterns, a pattern that the entire image matches most is selected (step S700). This may be visually selected by the operator with reference to the display mask, or the evaluation unit 424 may automatically select one that maximizes the image similarity calculated in step S550.

  Finally, in the pattern selected in step S700, the moving amount of the bed 120 to be corrected is calculated in the positioning unit 425 from the moving amount in the image alignment in step S550 and displayed on the display screen (step S800).

  Since the movement amount of the bed 120 is calculated by the above-described operation flow, the treatment control apparatus 900 moves the bed 120 based on the calculated movement amount, and thereafter performs radiation therapy.

  Next, the effects of this embodiment will be described.

  The radiation treatment apparatus 1 for irradiating radiation to the target area according to the first embodiment of the present invention described above comprises a bed 120 on which the object 130 is placed, which is capable of positioning the object 130 having the target area; An X-ray imaging apparatus for imaging 130 by X-ray to generate a fluoroscopic image, a setting unit 421 for setting a positioning reference area 520 on a treatment plan CT image imaged at the time of creation of a treatment plan, and a standard for a treatment plan CT image A deformation unit 422 that generates a deformed image obtained by changing the area 520, a projection unit 423 that projects a deformed image by simulating a system of an X-ray imaging apparatus and generates a projection image, a projection image and an X-ray imaging apparatus And an evaluation unit for obtaining a degree of coincidence with the X-ray fluoroscopic image captured by

  This makes it possible to create a template image corresponding to the deformation of the subject 130 at the time of treatment, and greatly improves the probability that the images of the region serving as the reference for positioning coincide, and the degree of coincidence compared to the prior art. be able to. Therefore, even if the surrounding internal structure is deformed from the time of treatment planning, it is possible to calculate the patient positioning that matches the position at the time of planning.

  In addition, since the positioning unit 425 for performing positioning calculation of the bed 120 based on the selected appropriate projection image and fluoroscopic image is further provided, deformation is taken into consideration even when there is patient deformation in bed positioning using the fluoroscopic image. The reference area in the subject 130 can be placed at the planned position, and positioning of the bed can be performed in a shorter time than in the conventional case, and the treatment time can be shortened.

  Furthermore, the X-ray imaging apparatus images the object 130 in at least two directions, and the projection unit 423 simulates the system of the X-ray imaging apparatus and projects in at least two directions to further improve the positioning accuracy. It can be done.

  Further, by further providing the input device 600 for specifying the reference area 520, the operator can specify with high accuracy the reference area 520 which becomes the reference of how to make deformation, and the deformation image to be the template image is made higher. It can be generated with precision.

  In the modification at step S400, it is possible to display the calculated displacement amount on the screen. This makes it possible to quantitatively grasp the deformation of the subject 130, which makes it easier to determine whether the treatment should be continued or interrupted, and the method of correction when correcting the state of the subject 130 is clearer. Become.

Example 2
A radiotherapy apparatus according to a second embodiment of the present invention will be described with reference to FIG. FIG. 5 is a view for explaining an example of a pattern of image deformation in the radiation treatment apparatus of the present embodiment.

  In the present embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. The same applies to the following embodiments.

  In the radiotherapy apparatus of this embodiment, the display device 500 of the radiotherapy apparatus 1 of Embodiment 1 displays the projection image and the deformation degree of the projection image.

  In the radiotherapy apparatus of the present embodiment, the deformation of the object 130 can be quantitatively grasped by displaying the selected deformation pattern on the display screen 510 of the display device 500 in step S700 shown in FIG. I have to.

  The deformation pattern display screen 510 is displayed as a deformation grid 550 on a three-dimensional CT image basically as shown in FIG. The following explains how to obtain this grid.

  The deformation is represented by the positions of control points 540 three-dimensionally arranged on the three-dimensional CT image.

  When there is no deformation, the control points 540 are arranged in a square lattice, and cubes having the control points 540 as vertices are arranged. Here, in the case of displaying a three-dimensional CT image, a three-dimensional cross section, for example, a cross section in which a body is cut into slices is selected and displayed, and a cross section to be displayed is moved to grasp a three-dimensional shape. In this display section, the above-mentioned cube group is displayed as a square grid. This is how to obtain the deformed grid 550 when there is no deformation.

  On the other hand, when there is a deformation, the control point 540 shifts from the square lattice, so the cube becomes a set of hexahedrons. When this is cut at the display cross section, it becomes a deformed grid deformed from a square. This is a modified grid 550 as shown in FIG.

  The other configurations and operations are substantially the same as the configurations and operations of the radiotherapy apparatus of the first embodiment described above, and the details will be omitted.

  Also in the radiotherapy apparatus of the second embodiment of the present invention, substantially the same effect as that of the radiotherapy apparatus of the first embodiment described above can be obtained.

  Further, by further providing the projection image and the display device 500 for displaying the degree of deformation of the projection image, it becomes possible to quantitatively grasp the amount of deformation for each place in the object 130. Therefore, it is possible to more easily determine whether the treatment should be continued or interrupted, and in the case of correcting the condition of the subject 130, the method of correction becomes clearer and the treatment is completed in a shorter time. It can be done.

Example 3
A radiation treatment apparatus according to a third embodiment of the present invention will be described with reference to FIG. FIG. 6 is a view showing an example of a screen for designating image deformation in the radiation treatment apparatus of the present embodiment.

  The radiation treatment apparatus according to the present embodiment further includes a deformation designation region 560 for specifying how to deform the treatment plan CT image by the deformation unit, in addition to the radiation treatment apparatus 1 according to the first embodiment, and the operator sets the deformation. It is a device that has been made to

  In the radiotherapy apparatus of the present embodiment, the deformation is designated from the display screen provided with the deformation designation area 560 as shown in FIG.

  In the deformation designation region 560, the deformation amounts as shown in the first and second embodiments are displayed on the three-dimensional CT image. The deformation amount is directly deformed by moving the control point 540 displayed on the screen by operating the input device 600. Alternatively, it can be designated numerically in the transformation designation area 560.

  In the deformation designation area 560, a plurality of deformation patterns are prepared in advance, and an image can be deformed by specifying deformation amounts for these. The deformation pattern is specified by, for example, a function.

  When a deformation amount is specified, the deformation unit 422 moves the control point 540 according to a function with reference to the reference area 520 or the center of the image. However, as in the first embodiment, the control point 540 surrounding the reference area 520 is not moved, and the reference area 520 is not deformed. An image can be freely deformed three-dimensionally by these.

  Alternatively, it is possible to select a deformation pattern applied to another image, for example an image of a past treatment day.

  The other configurations and operations are substantially the same as the configurations and operations of the radiotherapy apparatus of the first embodiment described above, and the details will be omitted.

  Also in the radiotherapy apparatus of the third embodiment of the present invention, substantially the same effect as the radiotherapy apparatus of the first embodiment described above can be obtained.

  In addition, since the operator can specify a deformation pattern by further including a deformation designation region 560 for specifying how to deform the treatment plan CT image by the deformation unit, only a deformation pattern closer to the actual deformation is searched Because the amount of calculation can be reduced, treatment in a shorter time becomes possible.

Example 4
A radiotherapy apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS. 7A and 7B. FIG. 7A is a view showing machine learning of a deformation pattern in the radiotherapy apparatus of the present embodiment, and FIG. 7B is a view showing a selection of a deformation pattern using a learning result.

  As shown in FIG. 7A, in the radiotherapy apparatus of this example, the radiotherapy apparatus 1 of Example 1 reads sets of a plurality of treatment plan CT images and projection images, and uses the pattern of deformation as learning data. It further comprises a machine learning device 700 for learning. Further, the deformation unit of the positioning calculation device 400 generates a deformed image by deforming other than the reference area 520 of the treatment plan CT image based on the deformation pattern learned by the machine learning device 700.

  In the radiotherapy apparatus of this embodiment, the machine learning apparatus 700 reads a treatment plan CT image and a projection image at an arbitrary timing other than the positioning time. The machine learning apparatus 700 learns the correlation between the CT image and the deformation pattern using an algorithm such as deep learning. This learning can be performed separately for each treatment site.

  Then, at the time of treatment, as shown in FIG. 7B, a CT image of the treatment target is input to the machine learning device 700, and deformation pattern candidates are estimated. Here, a plurality of deformation patterns with high correlation are estimated, and are evaluated by positioning calculation with the positioning calculation device 400.

  Also, it is possible to search for a pattern obtained by deforming the estimated deformation pattern as a reference.

  Here, when the deformation pattern is indicated by the function specified in the third embodiment, a pattern in which the deformation amount is increased or decreased can be easily created, and the amount of calculation can be reduced.

  The other configurations and operations are substantially the same as the configurations and operations of the radiotherapy apparatus of the first embodiment described above, and the details will be omitted.

  Also in the radiotherapy apparatus of the fourth embodiment of the present invention, substantially the same effect as that of the radiotherapy apparatus of the first embodiment described above can be obtained.

  The apparatus further includes a machine learning device 700 that reads a set of a plurality of treatment plan CT images and a projection image and machine-trains a pattern of deformation as learning data, and the deformation unit converts the pattern of deformation learned by the machine learning device 700. A deformation image is generated by deforming other than the reference area 520 of the treatment plan CT image based on that. In this case, since the machine learning apparatus 700 can learn the pattern of possible deformation from other data, the deformation pattern estimated at the time of treatment is also output that is close to the actual deformation of the object 130. The calculation of the rating at 400 is reduced. That is, only possible deformation patterns can be searched from the CT image at the time of treatment planning, deformation patterns can be determined with a smaller amount of calculation, and positioning in a short time can be performed.

Example 5
A radiation treatment apparatus according to a fifth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a view showing an example of a warning screen in the radiation treatment apparatus of this embodiment.

  The radiotherapy apparatus of this embodiment displays a warning in the display device 500 of the radiotherapy apparatus 1 of the first embodiment when the degree of deformation is larger than a predetermined threshold.

  In the radiotherapy apparatus of the present embodiment, the movement amount to which a warning should be issued is set in advance in the warning movement amount setting area 800 of the warning movement amount setting screen as shown in FIG.

  Then, in the positioning calculation device 400, the evaluation unit 424 calculates the movement amount from the position of the original square lattice for each control point 540 of the deformation pattern obtained by the calculation. When it is determined that the movement amount is larger than the value designated in the warning movement amount setting area 800, the movement amount is displayed on the display screen 510 as a warning display control point 810.

  The other configurations and operations are substantially the same as the configurations and operations of the radiotherapy apparatus of the first embodiment described above, and the details will be omitted.

  Also in the radiotherapy apparatus of the fifth embodiment of the present invention, substantially the same effect as that of the radiotherapy apparatus of the first embodiment described above can be obtained.

  In addition, when the degree of deformation is larger than a predetermined threshold value, the display device 500 may display an alert to allow the operator to easily grasp which region of the object 130 is largely deformed. You can quickly determine the impact of the treatment on the treatment. For this reason, appropriate deformation can be selected more quickly, and treatment in a shorter time becomes possible.

<Others>
The present invention is not limited to the above embodiments, and includes various modifications. The above embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described.

  In addition, part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Moreover, it is also possible to add, delete, and replace other configurations for part of the configuration of each embodiment.

  For example, although the case of directly detecting the target area has been described, the detection target is not limited to the target area, and one or more markers embedded in the periphery of the target area or high density areas in the object 130, such as ribs Etc. can be detected.

100 ... therapeutic radiation irradiating apparatus 120 ... bed 130 ... subject 200 ... X-ray tube (fluorescent part)
210: Detector (fluorescent part)
220 ... X-ray tube (fluorescent part)
230: Detector (fluorescent part)
240 ... X-ray fluoroscopic imaging control unit (perspective unit)
300 ... 3D image pickup apparatus 310 ... image server 400 ... positioning calculation apparatus (calculation apparatus)
410 communication unit 420 computing unit 421 setting unit 422 deformation unit 423 projection unit 424 evaluation unit 425 positioning unit 430 memory 510 display screen (display unit)
515 ... CT image 520 ... reference area 530 ... calculation start button 540 ... control point 550 ... deformation lattice 560 ... deformation designation area (designation section)
600 ... input device (input unit)
700 ... machine learning device (machine learning unit)
800 ... Warning movement amount setting area 810 ... Warning display control point 900 ... Treatment control device

Claims (9)

A radiation treatment apparatus for irradiating a target area with radiation, comprising:
A bed on which the subject is placed, which is capable of positioning the subject having the target area;
A fluoroscopic unit configured to image the subject with X-rays to generate a fluoroscopic image;
A positioning reference area is set on a treatment plan CT image captured at the time of preparation of a treatment plan, a deformed image obtained by deforming other than the reference area of the treatment plan CT image is generated, and the deformation image is A radiotherapy apparatus comprising: an arithmetic unit for simulating and projecting to generate a projection image; and evaluating a degree of coincidence between the projection image and an X-ray fluoroscopic image captured by the fluoroscopic unit. In the radiation treatment apparatus according to claim 1,
The arithmetic device includes a setting unit that sets the positioning reference area, a deformation unit that generates the deformation image, a projection unit that generates the projection image, and an evaluation that evaluates the degree of coincidence between the projection image and the X-ray fluoroscopic image A radiation treatment apparatus comprising: In the radiation treatment apparatus according to claim 2,
The radiotherapy apparatus, wherein the arithmetic unit further includes a positioning unit that performs positioning calculation of the bed based on an appropriate projection image and the fluoroscopic image. In the radiation treatment apparatus according to claim 2,
A radiation treatment apparatus, further comprising a display unit that displays the projection image and a degree of deformation of the projection image. In the radiation treatment apparatus according to claim 2,
The arithmetic device further includes a machine learning unit reading a set of a plurality of the treatment plan CT images and the projection image and performing machine learning as a pattern of deformation as learning data.
The radiation treatment apparatus, wherein the deformation unit is configured to deform a region other than the reference area of the treatment plan CT image based on a pattern of deformation learned by the machine learning unit to generate a deformation image. In the radiation treatment apparatus according to claim 2,
A radiation treatment apparatus, further comprising a designation unit that designates how to deform the treatment plan CT image by the deformation unit. In the radiation treatment apparatus according to claim 4,
The radiotherapy apparatus, wherein the display unit displays a warning when the degree of deformation is larger than a predetermined threshold. In the radiation treatment apparatus according to claim 2,
The radiotherapy apparatus further comprising an input unit for specifying the positioning reference area. In the radiation treatment apparatus according to claim 2,
The fluoroscopic unit images the subject in at least two directions;
The radiation treatment apparatus, wherein the projection unit simulates the system of the fluoroscopic unit and projects from at least two directions.

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