Image generation method and device based on ultrasonic patch, equipment and medium

Abstract

The invention discloses an image generation method and device based on an ultrasonic patch, equipment and a medium, and relates to the technical field of medical imaging. The method comprises the following steps: acquiring a dynamic ultrasonic image in a radiation process in real time by using an ultrasonic patch probe; fusing the dynamic ultrasonic image with a tumor CT / MRI image in a tumor radiotherapy planning device to obtain a fused image; the fused image is used for assisting related workers in determining an optimal radiotherapy point. According to the method, the imaging precision of image fusion can be improved, the tumor radiotherapy precision can be improved, besides better real-time dynamic imaging can be achieved, workers do not need to enter a treatment room on site for operation in batches, and the risk that the workers are irradiated can be better avoided.

Description

Technical Field

[0001] The present invention relates to the field of medical imaging technology, and in particular to an image generation method, device, equipment and medium based on an ultrasonic patch. Background Art

[0002] During the radiotherapy of tumors, the movements of human organs and tumors are very complex, which leads to problems such as deviation in tumor positioning and treatment accuracy. Especially for the organs in the chest and abdomen, due to the changes in the respiratory cycle, three problems occur: first, the images collected by CT (computed tomography) before treatment will be seriously distorted; second, the radioactive dose deposited in the tumor during radiotherapy deviates from the dose formulated in the radiotherapy plan, affecting the tumor cell killing effect; third, the radiation dose is deposited in the surrounding normal organs, causing unnecessary irradiation. Summary of the invention

[0003] The purpose of the present invention is to provide an image generation method, device, equipment and medium based on an ultrasound patch, which can improve the imaging accuracy of image fusion and help improve the accuracy of tumor radiotherapy.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] An image generation method based on an ultrasonic patch, comprising:

[0006] Use the ultrasound patch probe to obtain dynamic ultrasound images during the radiation process in real time;

[0007] The dynamic ultrasound image is fused with the tumor CT / MRI image in the tumor radiotherapy planning device to obtain a fused image; the fused image is used to assist relevant staff in determining the best radiotherapy point.

[0008] Optionally, an ultrasonic patch probe is used to obtain dynamic ultrasonic images during the radiation process in real time, specifically including:

[0009] By utilizing the phased array deflection and focusing characteristics of the ultrasonic patch probe, a combination of active avoidance and passive protection measures is used to avoid the influence of secondary ionizing radiation particles (neutrons, photons and electrons, etc.) generated by induced radioactivity during the operation of the radiotherapy accelerator on the ultrasonic patch circuit, thereby ensuring real-time acquisition of dynamic ultrasonic images during the radiation process.

[0010] Optionally, the active avoidance process is: based on the deflection and focusing characteristics of the phased array, by changing the pulse excitation delay time of the piezoelectric chip group, the ultrasonic beam deflection direction and focus are electronically controlled, and multi-angle detection and multi-point detection are performed to ensure that the reserved patch placement position is fully considered when designing the treatment beam field during TPS, to ensure that the patch can effectively image the tumor and surrounding critical organs while avoiding the incident path of the treatment beam, thereby preventing mutual interference between the ultrasonic patch imaging and the treatment beam.

[0011] Optionally, the passive protection includes special protection type and conventional protection type; the backing protection layer of the special protection type adopts a double-layer design, in which the top layer is an 8 mm thick tungsten-epoxy resin composite material and the bottom layer is a 6 mm thick tungsten-epoxy resin composite material; the backing protection layer of the conventional protection type adopts a single-layer design, which is a 6 mm thick tungsten-epoxy resin composite material.

[0012] Optionally, the dynamic ultrasound image is fused with a tumor CT / MRI image in a tumor radiotherapy planning device to obtain a fused image, specifically including:

[0013] Preprocessing the dynamic ultrasound image using image fusion software to obtain a preprocessed image;

[0014] The pre-processed image and the tumor CT / MRI image pre-stored in the tumor radiotherapy planning device are sequentially subjected to coordinate axis registration and size ratio matching to obtain a fused image.

[0015] Optionally, after obtaining the fused image, the method further includes: displaying the fused image to relevant staff via a display terminal.

[0016] The present invention also provides an image generation device based on an ultrasonic patch, which is applied to the image generation based on the ultrasonic patch as described above, and is characterized in that it includes: an ultrasonic patch probe, an ultrasonic imaging host, a signal transmission cable and an accelerator; the ultrasonic patch probe is connected to the ultrasonic imaging host through the signal transmission cable; the accelerator is arranged above the working position of the ultrasonic patch probe, and the accelerator's workstation and computer are connected to the ultrasonic imaging host.

[0017] Optionally, the ultrasonic patch probe specifically adopts a phased array ultrasonic patch probe.

[0018] The present invention also provides an electronic device, including a memory and a processor, wherein the memory is used to store a computer program, and the processor runs the computer program to enable the electronic device to execute the above-mentioned image generation method based on the ultrasound patch.

[0019] The present invention also provides a computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the above-mentioned image generation method based on the ultrasound patch.

[0020] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0021] The present invention discloses an image generation method, device, equipment and medium based on an ultrasonic patch, the method comprising using an ultrasonic patch probe to obtain a dynamic ultrasonic image in the radiation process in real time; fusing the dynamic ultrasonic image with a tumor CT / MRI image in a tumor radiotherapy planning device to obtain a fused image; the fused image is used to assist relevant staff in determining the best radiotherapy point. The present invention can improve the imaging accuracy of image fusion and help improve the accuracy of tumor radiotherapy. In addition to better real-time dynamic imaging, it does not require manual on-site entry into the treatment room for operation, which can better avoid the risk of radiation to staff. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0023] Figure 1 It is a schematic diagram of the flow of the image generation method based on the ultrasound patch of the present invention;

[0024] Figure 2 Schematic diagram of the deflection and focusing of the phased array ultrasonic patch probe in this embodiment;

[0025] Figure 3 This is a schematic diagram of the structure of a special protective phased array ultrasonic patch probe in this embodiment;

[0026] Figure 4 This is a schematic diagram of the structure of a conventional protective phased array ultrasonic patch probe in this embodiment;

[0027] Figure 5 This is a schematic diagram of a real-time ultrasound imaging fusion CT image system of an ultrasound patch probe in this embodiment;

[0028] Figure 6 This is a schematic diagram of an example of real-time ultrasound imaging fused with CT images in TPS in this embodiment;

[0029] Figure 7 This is a schematic diagram of the treatment interface of TPS intra-ultrasound real-time imaging fused with CT images in this embodiment;

[0030] Figure 8 This is a schematic diagram of the registration of a 3D ultrasound image and a 3D CT image of the volume change of the tumor itself in this embodiment;

[0031] Fig. 9 Schematic diagram of the treatment interface of TPS intra-ultrasound 3D real-time imaging fused with CT images in this embodiment. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] The purpose of the present invention is to provide an image generation method, device, equipment and medium based on an ultrasound patch, which can improve the imaging accuracy of image fusion and help improve the accuracy of tumor radiotherapy.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] like Figure 1 As shown, the present invention provides an image generation method based on an ultrasonic patch, which uses a flexible phased array ultrasonic patch probe to replace the traditional handheld probe to realize ultrasonic detection imaging, and uses real-time dynamic 2D / 3D ultrasonic images combined with tumor CT or MRI (Magnetic Resonance Imaging) images in TPS to generate fusion images for on-site radiotherapy comparison, so as to solve the shortcomings of the current image-guided radiotherapy that cannot obtain real-time dynamic images at all times, and the image accuracy of the ultrasonic probe for independent imaging of the tumor is low, and further improves the accuracy of radiotherapy for tumors. At the same time, the present invention does not need to use a series of complex operations in the process of executing respiratory gating technology to locate the tumor, and is non-invasive to the patient. In addition, by utilizing the characteristics of deflection focusing and simultaneous tracking of multiple targets of the phased array ultrasonic patch, when directly using ultrasonic images or computer reconstruction of imaging data to realize real-time two-dimensional and three-dimensional fusion of different tumor images (such as ultrasound and CT / MRI), there is no need to fix special material markers on the body surface as common reference points (such as metal objects). Finally, compared with the Clarity technology, in addition to being able to perform real-time dynamic imaging of tumors throughout the treatment process, the present invention does not require manual on-site entry into the treatment room for operation, which can better avoid the risk of radiation exposure to staff. It mainly includes the following steps:

[0036] Step 100: Using an ultrasonic patch probe to obtain dynamic ultrasonic images during the radiation process in real time.

[0037] Step 200: Fusing the dynamic ultrasound image with the tumor CT / MRI image in the tumor radiotherapy planning device to obtain a fused image; the fused image is used to assist relevant staff in determining the best radiotherapy point.

[0038] Based on the above processing steps, a specific embodiment is provided.

[0039] For the phased array ultrasonic patch probe, since the patch needs to be protected against ionizing radiation generated by the accelerator during operation, the ultrasonic patch designed in the present invention adopts a method that combines active avoidance and passive protection measures to ensure the normal operation of the ultrasonic piezoelectric crystal.

[0040] The specific implementation methods of active avoidance are as follows: Figure 2 As shown, the phased array can electronically control the deflection direction (refraction angle) and focus of the ultrasonic beam by changing the pulse excitation delay time of the piezoelectric chip group. That is, without changing the position of the probe, multi-angle detection and multi-point detection characteristics can be performed. When designing the treatment beam field (incident angle) of TPS, full consideration is given to reserving the patch placement position (the patch probe size is small enough, about 60x60mm) to ensure that the patch can effectively image the tumor and surrounding critical organs while avoiding the incident path of the treatment beam, thereby preventing the ultrasound patch imaging and the treatment beam from interfering with each other.

[0041] The specific design of passive protection is that according to the energy and type of therapeutic particles used by the radiotherapy accelerator, the patch is divided into two types:

[0042] The first type is a special protection type, which is suitable for the energy of gamma photons emitted by a type of radiotherapy equipment based on photon therapy, such as electron linear accelerators, is higher than the reaction threshold of most (γ.n) (>10MeV), and the unstable neutrons produced by the reaction of gamma photons with air, treatment beds and other materials cause a series of subsequent nuclear reactions that trigger radioactive particles (mainly β and γ rays). Or when the high-energy particles of the proton heavy ion cyclotron accelerator react with the air, treatment beds and other materials, the neutrons produce induced radioactivity (mainly β and γ rays). In these two situations, the backing material of the phased array ultrasound patch probe needs to be specially protected against neutrons, β and γ rays. Figure 3 This is a schematic diagram of a special protective structure.

[0043] First, the backing protective layer uses a double-layer design, in which the top layer is an 8mm thick tungsten-epoxy resin composite material (the mass ratio of nano-grade tungsten powder to epoxy resin is 7 / 1), which is mainly used to protect neutrons and induced radioactive rays (β, λ), in which the high content of nano-grade tungsten powder is mainly used to shield and absorb β and λ rays, and epoxy resin is used to slow down fast neutrons (reduce the energy of the absorbed part of fast neutrons). The bottom layer is a 6mm thick tungsten-epoxy resin composite material (the mass ratio of nano-grade tungsten powder to epoxy resin is 1 / 8), and the high content of epoxy resin is mainly used to absorb the slow neutrons after slowing down. At the same time, this material is also a good ultrasonic backing material, with a good ability to absorb the back sound waves emitted by the chip. This is because the two layers of the backing protective layer are of the same material, but the ratio is different, so the ability of the two as backing materials to absorb back sound waves is very close. At the same time, experiments have confirmed that when the material thickness of the mass ratio of nano-grade tungsten powder to epoxy resin is 1 / 8 and reaches 4mm, the sound wave has the best spatial pulse length, and it will not change after exceeding 4mm.

[0044] The phased array chip set uses 80 lead zirconate titanate piezoelectric ceramic chips, with a center point spacing of 0.5mm between each two chips, connected by a 3D printed top circuit and bottom circuit (gold), with an aperture of 2cm. The matching layer is composed of polyurethane and biological glue, with an acoustic impedance of about 5.4MRayl, and its thickness varies according to the different sound wave frequencies used. For example, when the sound wave frequency is 3MHz, the sound wave wavelength is 412.4μm, and the matching layer thickness is 103.4μm.

[0045] The second type is conventional protection, which is suitable for situations where the energy of therapeutic gamma photons emitted by electron linear accelerators and other radiotherapy instruments based on photon therapy is relatively small (<10MeV), which almost does not cause induced radioactivity and only requires simple conventional protection against the small amount of instantaneous secondary radiation generated by the operation of the accelerator. Figure 4 This is a schematic diagram of the structure of a conventional protective ultrasound patch, in which the backing protective layer is a 6mm thick tungsten-epoxy resin composite material (the mass ratio of nano-grade tungsten powder to epoxy resin is 1 / 8), which is mainly used to protect the low-dose rate instantaneous radiation (low-energy λ, β rays) generated by the treatment beam ionizing the air when the accelerator is running. At the same time, this layer of material also serves as a good ultrasound backing material. The rest of the structure is consistent with the special protective ultrasound patch structure.

[0046] By adjusting the mass ratio of nano-scale tungsten powder and epoxy resin in the backing material, it is possible to protect the electronic circuits in the ultrasonic patch from interference from ionizing radiation while also serving as a good ultrasonic backing material with a simple design and high integration.

[0047] The system structure consists of Figure 5As shown, the flexible ultrasound patch is connected to the ultrasound imaging host by a signal transmission cable. The cable mainly realizes the two functions of power supply and data transmission of the ultrasound patch probe. The ultrasound imaging host and the accelerator host are the same, which makes it easy to align the coordinate axes and size ratios of the real-time ultrasound image processed by the image fusion software with the CT / MRI image pre-stored in the TPS and then display it on the radiotherapy terminal.

[0048] The specific dynamic 2D / 3D ultrasound image registration and CT / MRI image in-software registration process (taking lung tumor as an example) is as follows: Figure 6-Figure 9 As shown:

[0049] (1) Figure 6 and Figure 7 As shown, the section image with the largest area of ​​the tumor in a certain inhalation / expiration state in the 4D-CT / MRI section image data set of the tumor in the TPS is used as the reference, and the intersection point of the longest diameter of the sagittal axis and the longest diameter of the coronal axis of the tumor in the section is marked as the first registration point. Then, a phased array ultrasound probe is used to perform full-focus two-dimensional imaging of multiple sections of the tumor and store it, and the ultrasound image of the section when the tumor has the largest area is quickly determined, and the intersection point of the longest diameter of the sagittal axis and the longest diameter of the coronal axis of the tumor is also marked as the second registration point. After the first registration point and the second registration point are overlapped and the image is rotated, it is enlarged in proportion.

[0050] (2) Based on the fused image after the registration of the largest section of the tumor area determined in step (1), the other 2D section images of the tumor are registered with the complete ultrasound image and CT image of the tumor area one by one. The tumor area registration data is used to complete the tumor volume registration of the phased array 3D real-time dynamic imaging and the 3D CT image.

[0051] (3) Figure 8 As shown in the figure, the position of the phased array ultrasound patch emitting and receiving sound waves is used as the origin of the tumor motion coordinate system, and the registration coincidence point in the maximum area of ​​the tumor determined in step (1) is used as the center point of the tumor motion. After the tumor is decomposed into volume pixels, the phased array probe is used to detect and monitor the relative three-dimensional coordinate position of each volume pixel point and the center point of the tumor motion, and finally the real-time dynamic ultrasound monitoring imaging of the tumor volume is completed to match the motion range of the tumor in 4D-CT.

[0052] (4) For some cystic or cystic-solid tumors (the tumor itself may have volume changes), it is also necessary to retrieve the image of the same tumor section in step (1) when the area is the smallest during the entire tumor volume change cycle and perform the same operations of marking the origin, proportional magnification and registration to jointly determine the volume change range of the tumor at the section position. After executing step (2), the 3D ultrasound image of the tumor volume change itself is registered with the 3D CT image. Fig. 9shown.

[0053] Working process:

[0054] (1) When formulating radiotherapy plans, oncologists and physicists fully consider the placement of ultrasound patches and plan using the deflection and focusing characteristics of the phased array to ensure that the patches can effectively image the tumor and surrounding organs at risk while avoiding the incident path of the treatment beam to prevent interference between ultrasound patch imaging and the treatment beam. Figure 2 shown.

[0055] (2) Before the formal implementation of radiotherapy, the ultrasound physician determines the location of the tumor based on the CT / MRI images in the TPS. After using the traditional ultrasound probe to accurately detect the tumor image, the specific attachment position of the ultrasound patch on the human body surface is marked. After the patch is successfully attached, it is debugged to a stable image.

[0056] (3) After the ultrasound patch forms a stable image, it is transmitted to the ultrasound imaging host through a signal transmission cable for processing. The real-time ultrasound image processed by the image fusion software is then aligned with the CT / MRI image pre-stored in the TPS for coordinate axis registration and size ratio matching before being displayed on the radiotherapy terminal.

[0057] (4) The radiation therapy physicist and technician will work together with the ultrasound physician and other directly related staff to confirm whether the imaging coordinate axes, size ratios, etc. of the fusion effect are accurately matched, and determine the optimal radiation therapy point after fully considering the relative positions of the surrounding critical organs.

[0058] (5) The reference interface of the fused real-time tumor dynamic treatment image is as follows Figure 7-Figure 8 As shown in the figure, the yellow solid line represents the clinical tumor target volume area, which is a static area. The blue dotted line represents the area where the tumor changes with physiological movements such as human breathing.

[0059] (6) Radiation therapy technicians implement radiation therapy in combination with fused images.

[0060] Therefore, this embodiment has the following beneficial effects:

[0061] The present invention is an auxiliary improvement that uses an ultrasonic patch imaging system to replace the traditional ultrasonic probe imaging system to solve the problem that the image-guided radiation therapy (IGRT) technology cannot obtain the relative motion image of the tumor organ and its surrounding normal tissues in real time during the current radiotherapy process. A flexible ultrasonic patch probe is used to replace the traditional handheld probe to achieve the real-time ultrasound image of the tumor during radiotherapy and the fusion of the CT or MRI image to form a real-time tumor dynamic treatment image, while eliminating the radiotherapy error caused by human physiological movement, further improving the accuracy of radiotherapy, and at the same time, there is no need to use respiratory gating technology and a series of complex operations during the execution process to locate the tumor, and it is non-traumatic to the patient. In addition, compared with the Clarity technology, in addition to better real-time dynamic imaging, the present invention does not require manual on-site entry into the treatment room for operation, which can better avoid the risk of radiation to the staff.

[0062] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0063] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An image generation method based on an ultrasonic patch, characterized in that: include: Use the ultrasound patch probe to obtain dynamic ultrasound images during the radiation process in real time; The dynamic ultrasound image is fused with the tumor CT / MRI image in the tumor radiotherapy planning device to obtain a fused image; the fused image is used to assist relevant staff in determining the best radiotherapy point.

2. The image generation method based on ultrasound patch according to claim 1, characterized in that: The ultrasonic patch probe is used to obtain dynamic ultrasonic images in real time during the radiation process, including: The phased array deflection and focusing characteristics of the ultrasonic patch probe are utilized to combine active avoidance and passive protection measures to avoid the influence of secondary ionizing radiation particles generated by induced radioactivity during the operation of the radiotherapy accelerator on the ultrasonic patch circuit, and to obtain dynamic ultrasonic images during the radiation process in real time.

3. The image generation method based on ultrasound patch according to claim 2, characterized in that: The active avoidance process is as follows: based on the deflection and focusing characteristics of the phased array, by changing the pulse excitation delay time of the piezoelectric chip group, the deflection direction and focus of the ultrasonic beam are electronically controlled, and multi-angle detection and multi-point detection are performed, so that the reserved patch placement position is fully considered when designing the treatment beam field during TPS, ensuring that the patch can effectively image the tumor and surrounding critical organs while avoiding the incident path of the treatment beam, thereby preventing mutual interference between the ultrasonic patch imaging and the treatment beam.

4. The method for generating images based on an ultrasound patch according to claim 2, characterized in that: The passive protection includes special protection type and conventional protection type; the backing protection layer of the special protection type adopts a double-layer design, in which the top layer is an 8mm thick tungsten-epoxy resin composite material and the bottom layer is a 6mm thick tungsten-epoxy resin composite material; the backing protection layer of the conventional protection type adopts a single-layer design, which is a 6mm thick tungsten-epoxy resin composite material.

5. The image generation method based on ultrasound patch according to claim 1, characterized in that: The dynamic ultrasound image is fused with the tumor CT / MRI image in the tumor radiotherapy planning device to obtain a fused image, specifically including: Preprocessing the dynamic ultrasound image using image fusion software to obtain a preprocessed image; The pre-processed image and the tumor CT / MRI image pre-stored in the tumor radiotherapy planning device are sequentially subjected to coordinate axis registration and size ratio matching to obtain a fused image.

6. The image generation method based on ultrasound patch according to claim 1, characterized in that: After the fused image is obtained, the method further includes: displaying the fused image to relevant staff via a display terminal.

7. An image generation device based on an ultrasonic patch, applied to the image generation based on an ultrasonic patch as claimed in any one of claims 1 to 3, characterized in that: include: Ultrasound patch probe, ultrasound imaging host, signal transmission cable and accelerator; The ultrasonic patch probe is connected to the ultrasonic imaging host through the signal transmission cable; the accelerator is arranged above the working position of the ultrasonic patch probe, and the workstation and computer of the accelerator are connected to the ultrasonic imaging host.

8. The image generation device based on ultrasound patch according to claim 7, characterized in that: The ultrasonic patch probe specifically adopts a phased array ultrasonic patch probe.

9. An electronic device, characterized in that: It includes a memory and a processor, the memory is used to store a computer program, and the processor runs the computer program to enable the electronic device to execute the image generation method based on the ultrasound patch according to any one of claims 1-6.

10. A computer-readable storage medium, characterized in that: It stores a computer program, and when the computer program is executed by a processor, it implements the image generation method based on the ultrasound patch as described in any one of claims 1-6.

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