Medical image processing device, treatment system, medical image processing method, and program
The medical image processing device enhances radiation therapy by utilizing CT images from the treatment phase through 3D-3D and 3D-2D positioning, improving patient alignment accuracy in radiation therapy.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOSHIBA ENERGY SYST & SOLUTIONS CORP
- Filing Date
- 2022-03-16
- Publication Date
- 2026-07-01
AI Technical Summary
Conventional radiation therapy methods fail to effectively utilize CT images taken during the treatment phase for patient positioning, relying instead on comparisons between DRR images and X-ray fluoroscopy images, which limits the accuracy of positioning.
A medical image processing device that includes a first image acquisition unit, a second image acquisition unit, a 3D-3D positioning execution unit, and a display control unit, which acquires and processes three-dimensional fluoroscopic images to calculate displacement amounts and display corrected DRR images for precise patient positioning.
Enables the effective utilization of CT images during the treatment phase for improved patient positioning, enhancing accuracy by incorporating 3D-3D and 3D-2D positioning processes to align the patient's position accurately.
Smart Images
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Abstract
Description
Technical Field
[0001] Embodiments of the present invention relate to a medical image processing apparatus, a treatment system, a medical image processing method, and a program.
Background Art
[0002] Radiation therapy is a treatment method for destroying a lesion in a patient's body by irradiating the lesion with radiation. At this time, the radiation needs to be accurately irradiated to the position of the lesion. This is because if the normal tissue in the patient's body is irradiated with radiation, it may affect the normal tissue. Therefore, when performing radiation therapy, first, at the treatment planning stage, computed tomography (CT) is performed in advance to three-dimensionally grasp the position of the lesion in the patient's body. Then, based on the grasped position of the lesion, the direction of radiation irradiation and the intensity of the irradiated radiation are planned so as to reduce the irradiation to normal tissue. After that, at the treatment stage, the radiation is irradiated to the lesion according to the irradiation direction and irradiation intensity planned at the treatment planning stage with the patient's position adjusted to the patient's position at the treatment planning stage.
[0003] During patient positioning in the treatment phase, 3D CT data is virtually placed in the treatment room, and the position of the mobile treatment table is adjusted so that the actual position of the patient lying on the table matches the position of this 3D CT data. More specifically, the patient's positional shift between the two images is determined by comparing (3D-3D positioning) a 3D CT image of the patient taken while lying on the table with a 3D CT image taken during treatment planning. Based on the positional shift determined by image comparison, the table is moved to match the position of lesions and bones within the patient's body with that of the treatment plan. Subsequently, the positioning is approved by comparing, or if necessary, comparing (3D-2D positioning) two images: an X-ray fluoroscopic image of the patient's body taken while lying on the table with a digitally reconstructed radiograph (DRR) image virtually reconstructed from the 3D CT image taken during treatment planning, and then radiation is irradiated to the lesion. [Prior art documents] [Patent Documents]
[0004] [Patent Document 1] Special Publication No. 2018-507073 [Overview of the project] [Problems that the invention aims to solve]
[0005] However, in conventional technology, DRR images reconstructed from 3D CT images taken during treatment planning are generally compared with X-ray fluoroscopy images. As a result, CT images taken during the treatment phase are not always effectively utilized for patient positioning.
[0006] The problem that this invention aims to solve is to provide a medical image processing device, a treatment system, a medical image processing method, and a program that can effectively utilize CT images taken during the treatment phase for patient positioning. [Means for solving the problem]
[0007] The medical image processing apparatus of this embodiment includes a first image acquisition unit, a second image acquisition unit, a 3D-3D positioning execution unit, and a display control unit. The first image acquisition unit acquires a first three-dimensional fluoroscopic image, which is a three-dimensional fluoroscopic image of the patient taken in a first stage. The second image acquisition unit acquires a second three-dimensional fluoroscopic image, which is a three-dimensional fluoroscopic image of the patient taken in a second stage that follows the first stage. The 3D-3D positioning execution unit performs 3D-3D positioning to calculate a first displacement amount between the first three-dimensional fluoroscopic image and the second three-dimensional fluoroscopic image. The display control unit displays a first DRR image generated from the second three-dimensional fluoroscopic image corrected based on the first displacement amount, and a two-dimensional fluoroscopic image of the patient on a display device. [Effects of the Invention]
[0008] According to embodiments of the present invention, CT images taken during the treatment phase can be effectively utilized for patient positioning. [Brief explanation of the drawing]
[0009] [Figure 1] A block diagram showing the schematic configuration of a treatment system equipped with the medical image processing device 100 of the embodiment. [Figure 2] A block diagram showing the schematic configuration of a treatment system equipped with the medical image processing device 100 of the embodiment, from a different angle than Figure 1. [Figure 3] A block diagram showing the schematic configuration of the medical image processing device 100 according to the embodiment. [Figure 4] A diagram illustrating the overview of the 3D-3D positioning process performed by the 3D-3D positioning execution unit 130. [Figure 5] A diagram showing an example of the execution result of the 3D-2D positioning process displayed by the display device 200. [Figure 6] A figure showing another example of the results of the 3D-2D positioning process displayed by the display device 200. [Figure 7]A flowchart showing an example of the processing flow performed by the medical image processing device 100 of the embodiment. [Figure 8] A flowchart illustrating another example of the processing flow performed by the medical image processing device 100 of the embodiment. [Modes for carrying out the invention]
[0010] The medical image processing apparatus, treatment system, medical image processing method, and program of the embodiment will be described below with reference to the drawings.
[0011] [Overall structure] Figure 1 is a block diagram showing the schematic configuration of a treatment system equipped with a medical image processing device 100 of an embodiment. The treatment system 1 comprises, for example, a treatment device 10, a medical image processing device 100, and a display device 200. The treatment device 10 comprises, for example, a patient table 12, a patient table control unit 14, a computed tomography (CT) device 16 (hereinafter referred to as "CT scanning device 16"), and a treatment beam irradiation gate 18.
[0012] The treatment table 12 is a movable treatment table that fixes a subject (patient) P receiving radiation therapy in a lying position, for example, by a fixing device. The treatment table 12 moves with the patient P fixed inside the annular CT scanning device 16 having an opening, according to the control from the treatment table control unit 14. The treatment table control unit 14 controls the translational mechanism and rotational mechanism provided on the treatment table 12 in order to align the patient's position to the irradiation position according to the movement amount signal output by the medical image processing device 100. The translational mechanism can drive the treatment table 12 in three axial directions, and the rotational mechanism can rotate the treatment table 12 around three axes. In other words, the treatment table control unit 14 moves the treatment table 12 with six degrees of freedom by controlling the translational mechanism and rotational mechanism of the treatment table 12. The degrees of freedom that the treatment table control unit 14 controls the treatment table 12 do not have to be six degrees of freedom; they may be fewer than six degrees of freedom (for example, four degrees of freedom) or more than six degrees of freedom (for example, eight degrees of freedom). The patient bed 12 is installed so as to be movable to both positions when the position where imaging is performed by the CT scanner 16 and the position where the treatment beam B is irradiated by the treatment beam irradiation gate 18 are different.
[0013] The CT scanner 16 is an imaging device for performing three-dimensional computed tomography. The CT scanner 16 has multiple radiation sources arranged inside the annular (gantry) opening, and each radiation source emits radiation to visualize the inside of the patient P's body. In other words, the CT scanner 16 emits radiation from multiple locations around the patient P. The radiation emitted from each radiation source in the CT scanner 16 is, for example, X-rays. The CT scanner 16 uses multiple radiation detectors arranged inside the annular opening to detect the radiation emitted from the corresponding radiation source that has passed through the patient P's body. Based on the energy levels of the radiation detected by each radiation detector, the CT scanner 16 generates a CT image of the inside of the patient P's body. The CT image of patient P generated by the CT scanner 16 is a three-dimensional digital image representing the degree of radiation attenuation at each location within the body as a digital value. The CT scanner 16 outputs the generated CT image to the medical image processing device 100. The imaging of the inside of the patient P's body in the CT scanner 16, that is, the irradiation of radiation from each radiation source and the generation of CT images based on the radiation detected by each radiation detector, is controlled, for example, by an imaging control unit (not shown). The CT scanner 16 is an example of a "first imaging device".
[0014] The treatment beam irradiation gate 18 irradiates the patient P with radiation as treatment beam B to destroy the tumor (lesion), which is the target area for treatment, located within the patient P's body. Treatment beam B can be, for example, X-rays, gamma rays, electron beams, proton beams, neutron beams, or heavy ion beams. Treatment beam B is irradiated linearly from the treatment beam irradiation gate 18 to the patient P (more specifically, the tumor inside the patient P's body). The irradiation of the treatment beam B at the treatment beam irradiation gate 18 is controlled, for example, by a treatment beam irradiation control unit (not shown). In the treatment system 1, the treatment beam irradiation gate 18 is an example of an "irradiation unit".
[0015] In radiation therapy, treatment plans are developed in a simulated treatment room environment. Specifically, the direction and intensity of the treatment beam B are planned by simulating the patient P's position on the treatment table 12 in the treatment room. This involves the physician identifying the target area on the CT image, or this process is performed automatically. Therefore, CT images at the treatment planning stage are imprinted with information such as the angle of the treatment table 12 and parameters representing the patient's position (e.g., supine or prone) within the treatment room. This is also true for CT images taken immediately before radiation therapy and for CT images taken during previous radiation therapy sessions. In other words, CT images taken inside the patient P's body by the CT scanner 16 are imprinted with parameters representing the angle of the treatment table 12 and the patient's position at the time of the scan.
[0016] In FIG. 1, the configuration of the treatment device 10 including the CT imaging device 16 and one fixed treatment beam irradiation portal 18 was shown. However, the configuration of the treatment device 10 is not limited to the above-described configuration. For example, instead of the CT imaging device 16, the treatment device 10 may be configured to include a CT imaging device in which a set of radiation sources and radiation detectors rotate inside an annular opening, a cone-beam (CB) CT device, a magnetic resonance imaging (MRI) device, an ultrasonic diagnostic device, or the like, and include an imaging device that generates a three-dimensional image of the inside of the patient P. For example, the treatment device 10 may be configured to include a plurality of treatment beam irradiation portals, such as further including a treatment beam irradiation portal that irradiates a treatment beam to the patient P from a horizontal direction. For example, the treatment device 10 may be configured such that one treatment beam irradiation portal 18 shown in FIG. 1 rotates 360 degrees with respect to the rotation axis in the horizontal direction X shown in FIG. 1, and irradiates the treatment beam to the patient P from various directions by rotating around the patient P. For example, instead of the CT imaging device 16, the treatment device 10 may include one or more imaging devices each composed of a set of a radiation source and a radiation detector, and the imaging device rotates 360 degrees with respect to the rotation axis in the horizontal direction X shown in FIG. 1, thereby imaging the inside of the patient P from various directions. Such a configuration is called a rotating gantry type treatment device. In this case, for example, one treatment beam irradiation portal 18 shown in FIG. 1 may be configured to rotate simultaneously about the same rotation axis as the imaging device. Further, in FIG. 1, the CT imaging device 16 and the treatment beam irradiation portal 18 are installed at positions close to each other. However, the CT imaging device 16 and the treatment beam irradiation portal 18 may be installed at positions separated from each other, and the positions of each other may be movable by the bed 12 on which the patient P lies.
[0017] The medical image processing device 100 outputs a movement amount signal for moving the bed 12 to the bed control unit 14 in order to align the position of the patient P in the same position as during the treatment plan. That is, the medical image processing device 100 outputs a movement amount signal for moving the patient P to a position and posture where the treatment beam B can be appropriately irradiated to the tumor or tissue to be treated in radiation therapy to the bed control unit 14.
[0018] The display device 200 displays an image for presenting various information in the treatment system 1 to the practitioner (such as a doctor) of radiation therapy using the treatment system 1, including during the process of aligning the position of patient P in the medical image processing device 100. The display device 200 displays, for example, various images such as a CT image or a fluoroscopic X-ray image output by the medical image processing device 100, or an image with various information superimposed on these images. Here, the various information includes, for example, patient information (age, gender, height, weight, etc.), imaging conditions of the image (imaging site, presence or absence of contrast agent, tube voltage, tube current, etc.), imaging date and time, or the position of the patient (head-up supine position, foot-down prone position, etc.). The display device 200 is, for example, a display device such as a liquid crystal display (LCD). The practitioner of radiation therapy can obtain information when performing radiation therapy using the treatment system 1 by visually checking the image displayed on the display device 200. The treatment system 1 may be configured to include a user interface such as an operation unit (not shown) operated by the practitioner of radiation therapy, and various functions executed by the treatment system 1 can be manually operated.
[0019] FIG. 2 is a block diagram showing the schematic configuration of the treatment system including the medical image processing device 100 of the embodiment from an angle different from FIG. 1. The treatment system 1 includes, in addition to the configuration shown in FIG. 1, for example, two radiation sources 20 (radiation source 20-1 and radiation source 20-2) and two radiation detectors 30 (radiation detector 30-1 and radiation detector 30-2).
[0020] The radiation source 20-1 irradiates radiation r-1 for fluoroscoping the inside of patient P from a predetermined angle. The radiation source 20-2 irradiates radiation r-2 for fluoroscoping the inside of patient P from a predetermined angle different from that of the radiation source 20-1. The radiation r-! and radiation r-2 are, for example, X-rays. FIG. 1 shows a case where X-ray imaging is performed on patient P fixed on the hospital bed 12 from two directions. In FIG. 1, illustration of the control unit that controls the irradiation of radiation r by the radiation source 20 is omitted.
[0021] Radiation detector 30-1 detects radiation r-1 that has been irradiated from radiation source 20-1 and passed through patient P's body, and generates an X-ray fluoroscopic image of patient P's body corresponding to the energy magnitude of the detected radiation r-1. Radiation detector 30-2 detects radiation r-2 that has been irradiated from radiation source 20-2 and passed through patient P's body, and generates an X-ray fluoroscopic image of patient P's body corresponding to the energy magnitude of the detected radiation r-2. Radiation detector 30 is arranged in a two-dimensional array of X-ray detectors, and generates a digital image as an X-ray fluoroscopic image, representing the energy magnitude of the radiation r that reached each X-ray detector as a digital value. Radiation detector 30 can be, for example, a flat panel detector (FPD), an image intensifier, or a color image intensifier. In the following description, each radiation detector 30 is assumed to be an FPD. The radiation detector 30 (FPD) outputs each generated X-ray fluoroscopic image to the medical image processing device 100. Note that in Figure 1, the control unit that controls the generation of X-ray fluoroscopic images by the radiation detector 30 is omitted from the illustration. The combination of the radiation source 20 and the radiation detector 30 is an example of a "second imaging device".
[0022] Figure 2 shows a configuration in which the treatment system 1 comprises two sets of radiation sources 20 and radiation detectors 30. However, the number of combinations of radiation sources 20 and radiation detectors 30 that the treatment system 1 comprises is not limited to two. For example, the treatment system 1 may comprise three or more sets of radiation sources 20 and radiation detectors 30. Alternatively, the treatment system 1 may comprise only one imaging device (one set of radiation sources 20 and radiation detectors 30). Hereinafter, the combination of radiation sources 20 and radiation detectors 30 may be referred to as an "X-ray imaging device."
[0023] The various components shown in Figures 1 and 2 may be connected to each other by wires, or they may be connected wirelessly, for example, by a LAN (Local Area Network) or a WAN (Wide Area Network).
[0024] [Medical Image Processing Equipment] The following describes the medical image processing apparatus 100 according to the embodiment. Figure 3 is a block diagram mainly showing the schematic configuration of the medical image processing apparatus 100 according to the embodiment. The medical image processing apparatus 100 includes, for example, a first image acquisition unit 110, a second image acquisition unit 120, a 3D-3D positioning execution unit 130, a 3D-2D positioning execution unit 140, and a display control unit 150.
[0025] Some or all of the components of the medical image processing device 100 are realized, for example, by a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Some or all of these components may be realized by hardware (including circuitry) such as LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), and GPU (Graphics Processing Unit), or by the cooperation of software and hardware. Some or all of the functions of these components may be realized by a dedicated LSI. The program may be stored in advance in a storage device (a storage device equipped with a non-transient storage medium) such as ROM (Read Only Memory), RAM (Random Access Memory), HDD (Hard Disk Drive), or flash memory provided by the medical image processing device 100, or it may be stored in a removable storage medium (a non-transient storage medium) such as a DVD or CD-ROM, and installed in the HDD or flash memory of the medical image processing device 100 when the storage medium is inserted into the drive device provided by the medical image processing device 100. The program may also be downloaded from another computer device via a network and installed in the HDD or flash memory of the medical image processing device 100.
[0026] The first image acquisition unit 110 acquires a first image of patient P before treatment and parameters (and / or treatment planning data) associated with that first image. The first image is a three-dimensional CT image representing the three-dimensional shape of the patient P's body, taken, for example, by a CT scanner 16 during the treatment planning stage when performing radiation therapy. The first image is used to determine the direction (path including inclination and distance) and intensity of the treatment beam B irradiated onto patient P during radiation therapy. The first image is an example of a "first three-dimensional fluoroscopic image".
[0027] The second image acquisition unit 120 acquires a second image of patient P immediately before the start of radiation therapy, and parameters associated with that second image. The second image is a three-dimensional CT image representing the three-dimensional shape of the inside of patient P's body, taken, for example, by a CT scanner 16, in order to adjust the position of patient P when irradiating with the treatment beam B during radiation therapy (i.e., positioning). In other words, the second image is an image taken by the CT scanner 16 immediately before irradiating with the treatment beam B from the treatment beam irradiation gate 18. In this case, the first image and the second image were taken at different times, but the method of taking each image is the same. The second image is an example of a "second three-dimensional fluoroscopic image".
[0028] The 3D-3D positioning execution unit 130 performs 3D-3D positioning processing to align the position of patient P when performing radiation therapy, based on the first image acquired by the first image acquisition unit 110 and the second image acquired by the second image acquisition unit 120. More specifically, for example, the medical image processing device 100 calculates the amount of three-dimensional displacement (hereinafter sometimes referred to as the "first displacement") between the first image acquired by the first image acquisition unit 110 and the second image acquired by the second image acquisition unit 120, and aligns the position between the first image and the second image by correcting the second image by the calculated first displacement. At this time, the medical image processing device 100 may output a movement amount signal to the bed control unit 14 to move the bed 12 on which the patient is placed and fixed by the first displacement, and the bed control unit 14 may move the bed 12 by the first displacement. Furthermore, if the CT scanning device 16 and the treatment beam irradiation gate 18 are installed at separate locations, the medical image processing device 100 may output a movement amount signal to the bed control unit 14 for moving the bed 12 by an amount equal to the distance between the CT scanning position and the irradiation position plus a first displacement amount, and the bed control unit 14 may move the bed 12 by an amount equal to the distance plus the first displacement amount.
[0029] Figure 4 is a diagram illustrating the overview of the 3D-3D positioning process performed by the 3D-3D positioning execution unit 130. The left side of Figure 4 represents a CT image (i.e., the first image) taken during the treatment planning stage (an example of the "first stage"), and the right side of Figure 4 represents a CT image (i.e., the second image) taken during the treatment stage (an example of the "second stage"). In Figure 4, the symbol A1 indicates the skull as captured in the first image, the symbol A2 indicates the anterior horn of the lateral ventricle as captured in the first image, the symbol A3 indicates the skull as captured in the second image, and the symbol A4 indicates the 2 The image shows the anterior horn of the lateral ventricle.
[0030] In conventional technology, when positioning a patient in radiotherapy, the DRR image generated from CT images taken during the treatment planning stage is compared with the X-ray fluoroscopy image taken during the treatment stage (3D-2D positioning), and the patient's bed 12 is moved by the specified amount of displacement to perform positioning. On the other hand, as shown in Figure 4, unlike X-ray fluoroscopy images, CT images include not only positional information about bones such as the skull, but also positional information about spaces such as the anterior horn of the lateral ventricle and internal organs. Therefore, by performing 3D-3D positioning processing by the 3D-3D positioning execution unit 130, more accurate positioning can be achieved.
[0031] The 3D-2D positioning execution unit 140 performs a 3D-2D positioning process that compares the DRR image generated from the second image with the patient's fluoroscopic image taken during the treatment phase. More specifically, the 3D-2D positioning execution unit 140 calculates the amount of three-dimensional displacement (hereinafter sometimes referred to as the "second displacement") between the DRR image generated from the second image, which has been corrected by a first displacement, and the patient's fluoroscopic image taken after moving the patient's bed 12, on which the patient is placed and fixed, by the first displacement. The radiation therapist approves the positioning, for example, if the calculated second displacement is less than a threshold. On the other hand, if the calculated second displacement is greater than or equal to the threshold, the bed control unit 14 moves the bed 12 by the calculated second displacement, takes another fluoroscopic image of the patient, and the 3D-2D positioning execution unit 140 performs the 3D-2D positioning process again using the acquired fluoroscopic image. The above process is repeated until the positioning is finally approved by the radiation therapist.
[0032] The 3D-2D positioning execution unit 140 is configured to perform a 3D-2D positioning process that compares the DRR image generated from the second image with the patient's fluoroscopic image, in addition to a 3D-2D positioning process that compares the DRR image generated from the first image with the patient's fluoroscopic image. More specifically, the 3D-2D positioning execution unit 140 calculates the amount of three-dimensional displacement (hereinafter sometimes referred to as the "third displacement") between the DRR image generated from the first image and the acquired patient's fluoroscopic image. The patient's fluoroscopic image acquired at this time may be taken after moving the bed 12 by the first displacement amount, as described above, or, if the CT scanner 16 and the treatment beam irradiation gate 18 are installed at separate locations, it may be taken after moving the bed 12 by the distance between the CT scanning position and the irradiation position plus the first displacement amount. The radiation therapist approves the positioning, for example, if the calculated third displacement amount is less than a threshold. On the other hand, if the calculated third displacement amount is greater than or equal to a threshold, the bed control unit 14 moves the bed 12 by the calculated third displacement amount, takes another X-ray fluoroscopic image of the patient, and the 3D-2D positioning execution unit 140 performs the 3D-2D positioning process again using the captured X-ray fluoroscopic image. The above process is repeated until the positioning is finally approved by the radiation therapist.
[0033] The series of processes performed by the 3D-3D positioning execution unit 130 and the 3D-2D positioning execution unit 140 described above can be applied not only to positioning before radiotherapy, but also, for example, to verify positioning after treatment using CT images taken after radiotherapy. Specifically, first, immediately after the treatment beam B is irradiated, a CT image of the patient is taken by the CT scanner 16. Next, the 3D-3D positioning execution unit 130 performs 3D-3D positioning processing between the acquired CT image and the CT image taken during the treatment planning stage. After that, the 3D-2D positioning execution unit 140 may generate a DRR image based on the amount of displacement identified by the 3D-3D positioning processing, and perform 3D-2D positioning between the generated DRR image and the X-ray fluoroscopy image at the time of positioning approval. Positioning can be verified by the amount of displacement identified by this 3D-3D positioning or 3D-2D positioning. Thus, the "second stage" is a concept that includes both immediately before radiotherapy (i.e., the treatment stage) and immediately after radiotherapy.
[0034] The display control unit 150 displays various information processed by the medical image processing device 100 on the display device 200. For example, the display control unit 150 may display the DRR image generated from the second image corrected by the first displacement amount and the patient's fluoroscopic image on the display device 200 in a synchronized manner. Similarly, if the DRR image is generated from the first image, the display control unit 150 may display the DRR image and the patient's fluoroscopic image on the display device 200 in a synchronized manner. In addition, for example, the display control unit 150 may display the results of 3D-3D positioning processing or the results of 3D-2D positioning processing on the display device 200. Furthermore, for example, after 3D-3D positioning is performed, the display control unit 150 may display an interface (IF) on the display device 200 that accepts a specification regarding whether to generate a DRR image based on the first image and / or the second image and perform 3D-2D positioning processing.
[0035] Figure 5 shows an example of the results of a 3D-2D positioning process displayed by the display device 200. In Figure 5, the Acquisition CT tab shows the results of a 3D-2D positioning process that compares the DRR image generated from the second image with the patient's fluoroscopic image, the Treatment Planning CT tab shows the results of a 3D-2D positioning process that compares the DRR image generated from the first image with the patient's fluoroscopic image, and the Summary tab shows summary information of the results of the 3D-2D positioning process. Figure 5 shows an example where the radiotherapist selects the Acquisition CT tab, and the results of a 3D-2D positioning process that compares the DRR image generated from the second image with the patient's fluoroscopic image are displayed on the display device 200. More generally, the display device 200 may display these two 3D-2D positioning process results in a switchable format using an arbitrary interface such as buttons or checkboxes, or it may display multiple results simultaneously on a single screen.
[0036] In Figure 5, region R1 represents a warning message regarding the execution of 3D-2D positioning processing using the DRR image generated from the second image. Alternatively, as a warning, the display device 200 may alert the radiation therapist by changing the color of the DRR image indicated by region R2 or the color of its border. The message displayed in region R1 may be displayed at all times, or it may be displayed as a pop-up, for example, when the DRR image of the acquired CT is displayed or when positioning calculations are performed. Furthermore, after the positioning has been approved, a message prompting further warning may be displayed when the amount of movement is transmitted to the treatment table 12. This allows the radiation therapist to accurately recognize, without misunderstanding, which DRR image is being used for 3D-2D positioning processing.
[0037] Region R3 represents the result of the 3D-3D positioning process performed before the 3D-2D positioning process. Region R4 represents the result of the 3D-2D positioning process using the DRR image generated from the second image. In this way, by displaying the results of both the 3D-3D positioning process and the 3D-2D positioning process together, the radiation therapist can confirm whether the patient's positioning has been performed appropriately.
[0038] Figure 6 shows another example of the execution result of the 3D-2D positioning process displayed by the display device 200. As an example, Figure 6 shows a scene where the radiation therapist has selected the summary tab on the display device 200. In Figure 6, region R5 represents the execution result of the 3D-2D positioning process using the DRR image generated from the second image, and region R6 represents the execution result of the 3D-2D positioning process using the DRR image generated from the first image. As shown by region R7, if the discrepancy between the execution result of the 3D-2D positioning process using the DRR image generated from the second image and the execution result of the 3D-2D positioning process using the DRR image generated from the first image exceeds a threshold, the display control unit 150 displays information on the display device 200 indicating that the discrepancy is large. The message displayed in region R7 may be displayed at all times, or it may be displayed as a pop-up, for example, when the 3D-2D positioning calculation is completed or when the amount of movement is transmitted to the treatment table 12. Furthermore, for example, after a message is displayed, a screen to confirm the results of the 3D-3D positioning could be automatically displayed. This would allow the radiation therapist to confirm whether the patient's positioning has been performed correctly.
[0039] Next, with reference to Figure 7, the processing flow performed by the medical image processing device 100 will be described. Figure 7 is a flowchart showing an example of the processing flow performed by the medical image processing device 100.
[0040] First, the first image acquisition unit 110 acquires a first image of patient P taken by the CT scanner 16 during the treatment planning stage (step S100). Next, the bed control unit 14 moves the bed 12 to the CT scanning position (step S102). Then, the second image acquisition unit 120 acquires a second image of patient P taken by the CT scanner 16 using the CT scanner (step S104).
[0041] Next, the 3D-3D positioning execution unit 130 performs 3D-3D positioning processing to align the patient P's position when performing radiation therapy, based on the first image acquired by the first image acquisition unit 110 and the second image acquired by the second image acquisition unit 120 (step S106). Next, the bed control unit 14 moves the bed 12 by the first displacement amount identified by the 3D-3D positioning processing (step S108).
[0042] After moving the bed 12, the medical image processing device 100 takes an X-ray fluoroscopic image of patient P using the X-ray imaging device (step S110). Next, the 3D-2D positioning execution unit 140 performs a 3D-2D positioning process to calculate a second displacement amount between the DRR image generated from the second image corrected by the first displacement amount and the X-ray fluoroscopic image (step S112).
[0043] Next, the medical image processing device 100 determines whether the positioning has been approved by the radiation therapist (step S114). More specifically, the medical image processing device 100 may determine whether the positioning has been manually approved by the radiation therapist via an interface (IF) on the display device 200, or it may automatically determine whether the positioning has been approved by determining whether the calculated second displacement is within a threshold.
[0044] If it is determined that the positioning has been approved by the radiation therapist, the medical image processing device 100 confirms the positioning and terminates the processing in this flowchart. On the other hand, if it is determined that the positioning has not been approved by the radiation therapist, the bed control unit 14 moves the bed 12 by the second displacement amount identified by the 3D-2D positioning process (step S116), and returns the process to step S110.
[0045] Based on the flowchart described above, the medical image processing device 100 corrects the second image using the first displacement amount identified by the 3D-3D positioning process, and then performs a 3D-2D positioning process based on the DRR image generated from the corrected second image and the X-ray fluoroscopy image taken of patient P after moving the treatment table by the first displacement amount. This makes it possible to effectively utilize the CT images taken during the treatment phase for patient positioning.
[0046] In the flowchart of Figure 7, in step S108, the bed control unit 14 moves the bed 12 by the first displacement amount identified by the 3D-3D positioning process. However, the process in step S108 may be omitted, or if the CT scanner 16 and the treatment beam irradiation gate 18 are located at separate positions, the process in step S108 may be to move the bed 12 by the distance between the CT scanning position and the irradiation position plus the first displacement amount. Furthermore, the process in step S112 may be omitted, in which case the radiotherapist approves the positioning in step S114 by visually confirming the generated DRR image and the captured X-ray fluoroscopy image.
[0047] Next, with reference to Figure 8, the processing flow performed by the medical image processing device 100 will be described. Figure 8 is a flowchart showing another example of the processing flow performed by the medical image processing device 100.
[0048] First, the first image acquisition unit 110 acquires a first image of patient P taken by the CT scanner 16 during the treatment planning stage (step S200). Next, the bed control unit 14 moves the bed 12 to the CT scanning position (step S202). Next, the second image acquisition unit 120 acquires a second image of patient P taken by the CT scanner 16 in the CT scanner (step S204).
[0049] Next, the 3D-3D positioning execution unit 130 performs 3D-3D positioning processing to align the position of patient P when performing radiation therapy, based on the first image acquired by the first image acquisition unit 110 and the second image acquired by the second image acquisition unit 120 (step S206). Next, the bed control unit 14 moves the bed 12 by the first displacement amount identified by the 3D-3D positioning processing (step S208).
[0050] After moving the bed 12, the medical image processing device 100 takes an X-ray fluoroscopic image of patient P using the X-ray imaging device (step S210). Next, the medical image processing device 100 receives a specification on the interface (IF) on the display device 200 regarding whether or not to perform 3D-2D positioning processing using the second image (step S212). If it is determined that 3D-2D positioning processing using the second image should be performed, the 3D-2D positioning execution unit 140 performs 3D-2D positioning processing to calculate a second displacement amount between the DRR image generated from the second image corrected by a first displacement amount and the X-ray fluoroscopic image (step S214). On the other hand, if it is not determined that 3D-2D positioning processing using the second image should be performed, the 3D-2D positioning execution unit 140 performs 3D-2D positioning processing to calculate a third displacement amount between the DRR image generated from the first image and the X-ray fluoroscopic image (step S216). At this time, in step S214 and / or step S216, the display control unit 150 displays the DRR image and the X-ray fluoroscopy image in sync with the display device 200.
[0051] Next, the medical image processing device 100 determines whether the positioning has been approved by the radiation therapist (step S218). More specifically, the medical image processing device 100 may determine whether the positioning has been manually approved by the radiation therapist via an interface (IF) on the display device 200, or it may automatically determine whether the positioning has been approved by determining whether the calculated second or third displacement amount is within a threshold.
[0052] If it is determined that the positioning has been approved by the radiation therapist, the medical image processing device 100 confirms the positioning and terminates the processing in this flowchart. On the other hand, if it is determined that the positioning has not been approved by the radiation therapist, the bed control unit 14 moves the bed 12 by the second or third displacement amount identified by the 3D-2D positioning process (step S220), and returns the process to step S210.
[0053] Based on the flowchart described above, the medical image processing device 100 receives a specification regarding whether to perform 3D-2D positioning using a second image corrected by the first displacement amount identified by the 3D-3D positioning process, or to perform 3D-2D positioning using the first image. The device then determines which 3D-2D positioning process to perform according to the specification of the radiation therapist. This enhances convenience for the radiation therapist.
[0054] In the flowchart of Figure 8, in step S208, the bed control unit 14 moves the bed 12 by the first displacement amount determined by the 3D-3D positioning process. However, as with the flowchart of Figure 7, the process in step S208 may be omitted, or if the CT scanner 16 and the treatment beam irradiation gate 18 are installed at separate locations, the process in step S208 may be to move the bed 12 by the distance between the CT scanning position and the irradiation position plus the first displacement amount. Furthermore, the process in step S220 may be omitted, in which case the processes in step S214 and step S216 may be executed in a switchable manner.
[0055] According to at least one embodiment described above, the medical image processing device 100 corrects the second image using a first displacement amount identified by 3D-3D positioning processing, and performs 3D-2D positioning processing based on the DRR image generated from the corrected second image and the X-ray fluoroscopy image taken of patient P after moving the treatment table by the first displacement amount. This makes it possible to effectively utilize the CT images taken during the treatment stage for patient positioning.
[0056] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]
[0057] 1…Treatment system, 10…Treatment device, 12…Treatment table, 14…Treatment table control unit, 16…CT scanning device, 18…Treatment beam irradiation gate, 100…Medical image processing device, 110…First image acquisition unit, 120…Second image acquisition unit, 130…3D-3D positioning execution unit, 140…3D-2D positioning execution unit, 150…Display control unit, 200…Display device
Claims
1. A first image acquisition unit acquires a first three-dimensional fluoroscopic image, which is a three-dimensional fluoroscopic image of the patient taken in the first stage, A second image acquisition unit acquires a second three-dimensional fluoroscopic image of the patient, which is a three-dimensional fluoroscopic image taken in a second stage that is later than the first stage, A 3D-3D positioning execution unit that performs 3D-3D positioning to calculate a first displacement amount between the first three-dimensional perspective image and the second three-dimensional perspective image, The system includes a display control unit that displays on a display device a first DRR image generated from the second three-dimensional fluoroscopic image corrected based on the first displacement amount, and a two-dimensional fluoroscopic image of the patient taken after moving the bed on which the patient is placed and fixed by the first displacement amount in the second step. Medical image processing equipment.
2. The system further includes a 3D-2D positioning execution unit that performs 3D-2D positioning to calculate a second displacement amount between a first DRR image generated from the second three-dimensional fluoroscopic image corrected based on the first displacement amount and the two-dimensional fluoroscopic image of the patient. The display control unit causes the display device to further display information regarding the second displacement amount. The medical image processing apparatus according to claim 1.
3. The display control unit causes the display device to display information regarding the first displacement amount when the 3D-2D positioning is performed. The medical image processing apparatus according to claim 2.
4. When the display control unit displays information regarding the second displacement amount on the display device, it also displays information on the display device indicating that the second displacement amount is calculated based on the second three-dimensional perspective image. The medical image processing apparatus according to claim 2 or 3.
5. The 3D-2D positioning execution unit further performs 3D-2D positioning to calculate a third displacement amount between the second DRR image generated from the first three-dimensional fluoroscopic image and the two-dimensional fluoroscopic image of the patient. A medical image processing apparatus according to any one of claims 2 to 4.
6. The medical image processing device further includes a receiving unit that receives a specification for performing 3D-2D positioning to calculate the second displacement amount between the first DRR image and the two-dimensional fluoroscopic image, or for performing 3D-2D positioning to calculate the third displacement amount between the second DRR image and the two-dimensional fluoroscopic image. The medical image processing apparatus according to claim 5.
7. The display control unit displays the information regarding the second displacement and the information regarding the third displacement in accordance with the display device, and if the discrepancy between the second displacement and the third displacement is greater than or equal to a threshold, it displays information indicating that the discrepancy is large on the display device. The medical image processing apparatus according to claim 5 or 6.
8. A medical image processing apparatus according to any one of claims 1 to 7, A treatment apparatus comprising: an irradiation unit for irradiating the patient with radiation; a first imaging device for capturing the first three-dimensional fluoroscopic image and the second three-dimensional fluoroscopic image; a second imaging device for capturing the two-dimensional fluoroscopic image; a patient bed; and a patient bed control unit for controlling the movement of the patient bed. A treatment system equipped with [the following features].
9. Computers The first three-dimensional fluoroscopic image, which is a three-dimensional fluoroscopic image of the patient taken in the first stage, is obtained. A second three-dimensional fluoroscopic image of the patient, which is a three-dimensional fluoroscopic image taken in the second stage after the first stage, is obtained. 3D-3D positioning is performed to calculate a first displacement between the first three-dimensional perspective image and the second three-dimensional perspective image. The display device displays a first DRR image generated from the second three-dimensional fluoroscopic image corrected based on the first displacement amount, and a two-dimensional fluoroscopic image of the patient taken in the second step after moving the bed on which the patient is placed and fixed by the first displacement amount. Medical image processing methods.
10. On the computer, In the first stage, a first three-dimensional fluoroscopic image of the patient, which is the image taken in the first stage, is obtained. A second three-dimensional fluoroscopic image of the patient, which is a three-dimensional fluoroscopic image taken in the second stage after the first stage, is obtained. Perform 3D-3D positioning to calculate the first displacement amount between the first three-dimensional perspective image and the second three-dimensional perspective image. The display device displays a first DRR image generated from the second three-dimensional fluoroscopic image corrected based on the first displacement amount, and a two-dimensional fluoroscopic image of the patient taken in the second step after moving the bed on which the patient is placed and fixed by the first displacement amount. program.