Scattering correction method, device, equipment and storage medium

Abstract

The present invention discloses a scatter correction method, device, equipment and storage medium, the method comprising: obtaining an initial projection image obtained by using a photon counting detector; wherein the initial projection image corresponds to at least two target imaging parameter data; based on preset mapping data, determining a target scatter kernel function corresponding to each of the target imaging parameter data; wherein the preset mapping data characterizes a mapping relationship between at least two preset imaging parameter data and a preset scatter kernel function; based on the initial projection image and each of the target scatter kernel functions, determining a scatter correction image; based on the scatter correction image, performing a correction operation on the initial projection image to obtain a target projection image. The embodiment of the present invention solves the problem that the traditional scatter correction method is not applicable to photon counting detectors, reduces the difficulty of upgrading the detector, and improves the image quality of the target projection image.

Description

Technical Field

[0001] The present invention relates to the field of medical imaging technology, and in particular to a scatter correction method, device, equipment and storage medium. Background Art

[0002] X-ray imaging systems based on tubes and detectors are widely used in industries, medical fields, etc. to achieve non-destructive internal detection and inspection. Currently, an important method to improve image quality is to replace traditional detectors with photon counting detectors. Photon counting detectors are a type of detection device that directly detects extremely weak light pulses. They use the single photon detection technology of photomultiplier tubes to detect multiple discrete weak light pulse signals.

[0003] During the imaging process of the imaging system, the X-rays received by the detector usually include transmitted rays and scattered rays. The transmitted rays constitute the projected image, while the scattered rays constitute the noise and image artifacts in the projected image. Therefore, the presence of scattered rays will reduce the contrast of the image and thus reduce the image quality. The traditional scatter correction algorithm is no longer applicable to the scatter correction of photon counting detectors, which increases the difficulty of detector upgrades. Summary of the invention

[0004] The embodiments of the present invention provide a scatter correction method, device, equipment and storage medium to solve the problem that the traditional scatter correction method is not suitable for photon counting detectors, reduce the difficulty of upgrading the detector, and improve the image quality of the target projection image.

[0005] According to an embodiment of the present invention, a scatter correction method is provided, the method comprising:

[0006] Acquire an initial projection image obtained by using a photon counting detector; wherein the initial projection image corresponds to at least two target imaging parameter data;

[0007] Based on preset mapping data, determining target scattering kernel functions corresponding to each of the target imaging parameter data; wherein the preset mapping data represents a mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function;

[0008] Determining a scatter correction image based on the initial projection image and each of the target scatter kernel functions;

[0009] A correction operation is performed on the initial projection image based on the scatter correction image to obtain a target projection image.

[0010] According to another embodiment of the present invention, a scatter correction device is provided, the device comprising:

[0011] An initial projection image acquisition module is used to acquire an initial projection image obtained by using a photon counting detector; wherein the initial projection image corresponds to at least two target imaging parameter data;

[0012] A target scattering kernel function determination module is used to determine the target scattering kernel function corresponding to each of the target imaging parameter data based on preset mapping data; wherein the preset mapping data represents a mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function;

[0013] A scatter correction image determination module, configured to determine a scatter correction image based on the initial projection image and each of the target scatter kernel functions;

[0014] The target projection image determination module is used to perform a correction operation on the initial projection image based on the scatter correction image to obtain a target projection image.

[0015] According to another embodiment of the present invention, there is provided an electronic device, the electronic device comprising:

[0016] at least one processor; and

[0017] a memory communicatively connected to the at least one processor; wherein,

[0018] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the scatter correction method described in any embodiment of the present invention.

[0019] According to another embodiment of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the scatter correction method described in any embodiment of the present invention when executed.

[0020] The technical solution of the embodiment of the present invention adopts a photon counting detector to determine an initial projection image based on at least two target imaging parameter data, determine a target scattering kernel function corresponding to each of the target imaging parameter data based on preset mapping data that characterizes the mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function, determine a scattering correction image based on the initial projection image and each of the target scattering kernel functions, perform a correction operation on the initial projection image based on the scattering correction image, and obtain a target projection image, thereby solving the problem that the traditional scattering correction method is not suitable for photon counting detectors, reducing the difficulty of upgrading the detector, and improving the image quality of the target projection image.

[0021] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 creative work.

[0023] Figure 1 A flow chart of a scatter correction method provided in Embodiment 1 of the present invention;

[0024] Figure 2 A schematic diagram of an energy spectrum distribution diagram provided in Embodiment 1 of the present invention;

[0025] Figure 3 A flow chart of a scatter correction method provided in Embodiment 2 of the present invention;

[0026] Figure 4 A schematic diagram of the structure of a scatter correction device provided in Embodiment 3 of the present invention;

[0027] Figure 5 This is a schematic diagram of the structure of an electronic device provided in Embodiment 4 of the present invention. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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 should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] Embodiment 1

[0031] Figure 1 This is a flow chart of a scatter correction method provided in Embodiment 1 of the present invention. This embodiment is applicable to the case of performing scatter correction on a projection image determined based on a photon counting detector. The method can be performed by a scatter correction device. The scatter correction device can be implemented in the form of hardware and / or software. The scatter correction device can be configured in a terminal device. For example, the terminal device can be an X-ray-based imaging system. Figure 1 As shown, the method includes:

[0032] S110, acquiring an initial projection image obtained by using a photon counting detector.

[0033] In this embodiment, the detector used by the imaging system for generating the initial projection image is a photon counting detector, and the initial projection image corresponds to at least two target imaging parameter data.

[0034] Exemplarily, the imaging system includes but is not limited to CT (Computed Tomography) system, CBCT (Cone beam CT) system, PET-CT system, FBCT (Fan beam CT) or radiotherapy system, etc. Among them, PET (Positron Emission Computed Tomography) is a new imaging technology that can display the metabolism of biological molecules, receptors and neurotransmitter activities. The imaging system used is not limited here.

[0035] When the photon energy of a traditional detector is low, the corresponding responsivity of the detector is also small, so the contribution of low photon energy to the optical pulse signal is limited. A photon counting detector is a detection device that directly detects extremely weak optical pulses. By using the single photon detection technology of a photomultiplier tube and setting at least two target imaging parameter data, it can detect at least two discrete weak optical pulse signals corresponding to the object under test. The imaging system generates an initial projection image by performing image reconstruction operations on multiple weak optical pulse signals. The responsivity of the photon counting detector is approximately constant over the entire photon energy range, which is equivalent to increasing the weighted ratio of low photon energy to the optical pulse signal. At the same time, low photon energy carries a large amount of contrast information. Therefore, the image quality of the initial projection image obtained using a photon counting detector is higher.

[0036] Specifically, the target imaging parameter data may be used to characterize parameter values ​​of the target imaging parameters required when acquiring the initial projection image.

[0037] S120 , determining target scattering kernel functions corresponding to each target imaging parameter data based on preset mapping data.

[0038] In this embodiment, the preset mapping data represents a mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function.

[0039] Scattering occurs during the interaction between X-rays and matter. Scattered photons may be deflected at any angle between 0 and 180 degrees. Backscattering (deflection angle greater than 90 degrees) is dominant for low-energy photons, while forward scattering (deflection angle less than 90 degrees) is dominant for high-energy photons. Therefore, the photon pulse signal detected by the photon counting detector usually contains signals generated by scattered photons, which can cause artifacts in the initial projection image.

[0040] Specifically, the preset scattering kernel function can be used to characterize the number of scattered photons or the scattering ratio caused by any scattering point on the photon counting detector to other sampling points. Exemplarily, the horizontal coordinate of the preset scattering kernel function is the distance between the scattering point and the sampling point, and the vertical coordinate is the number of scattered photons or the scattering ratio. Specifically, the projection area of ​​the object under test may cover the entire sampling area or part of the sampling area of ​​the photon counting detector, and the scattering point is the area on the photon counting detector covered by the projection area of ​​the object under test. The initial projection image can reflect the sampling area of ​​the photon counting detector covered by the projection area of ​​the object under test.

[0041] In an optional embodiment, the target imaging parameter data includes a target photon energy segment, and accordingly, the method further includes: obtaining an energy spectrum distribution diagram corresponding to the photon counting detector, and performing a segmentation operation on the energy spectrum distribution diagram based on at least two preset photon energy segments to obtain at least two energy spectrum interval data; determining preset scattering kernel functions corresponding to each energy spectrum interval data, and generating preset mapping data based on each preset photon energy segment and each preset scattering kernel function; wherein the preset mapping data characterizes a mapping relationship between each preset photon energy segment and a preset scattering kernel function.

[0042] Specifically, the target photon energy range can be used to characterize the photon energy range required for acquiring the initial projection image. Exemplarily, the target photon energy range can be 40-80 KeV or 80-120 KeV.

[0043] Specifically, the energy spectrum distribution diagram can be used to characterize the relationship between the preset photon energy and the number of photons. In an optional embodiment, obtaining the energy spectrum distribution diagram corresponding to the photon counting detector includes: based on at least two preset photon energies, obtaining the attenuation rates corresponding to the photon counting detector and at least two reference phantoms respectively; wherein the thickness of each reference phantom is different; for each reference phantom, based on at least two attenuation rates corresponding to the current reference phantom, constructing an attenuation rate equation; based on each attenuation rate equation, determining the energy spectrum distribution diagram corresponding to the photon counting detector.

[0044] Specifically, for each reference phantom, based on at least two preset photon energies, a photon counting detector is used to scan the current reference phantom respectively to obtain at least two attenuation rates corresponding to the current reference phantom.

[0045] Among them, exemplary, the decay rate equation satisfies the formula:

[0046]

[0047] Among them, x i represents the i-th reference motif, μ ρ represents the mass attenuation coefficient, ρ represents the density of the reference model, E j represents the jth preset photon energy, ΔE represents the width of the discrete energy interval, ΔE=E max / (n-1), F(E j ) represents the normalized energy spectrum distribution.

[0048] Figure 2 This is a schematic diagram of an energy spectrum distribution diagram provided by Embodiment 1 of the present invention. Specifically, the abscissa of the energy spectrum distribution diagram is the photon energy, and the ordinate is the number of photons. Figure 2Three preset energy segments are shown, namely, energy segment A, energy segment B and energy segment C. Based on energy segment A, energy segment B and energy segment C, a segmentation operation is performed on the energy spectrum distribution diagram to obtain three energy spectrum interval data, wherein each energy spectrum interval data respectively represents the number of photons corresponding to the corresponding preset photon energy segment in the energy spectrum distribution diagram.

[0049] Specifically, determining the preset scattering kernel functions corresponding to each energy spectrum interval data includes: inputting each energy spectrum interval data into a pre-built Monte Carlo simulation system to obtain the output preset scattering kernel functions corresponding to each energy spectrum interval data.

[0050] Among them, the Monte Carlo simulation system is a simulation system built based on the system environment of the imaging system. The Monte Carlo simulation method is a random simulation method based on probability and statistical theory methods, which can accurately describe the characteristics of things and reflect the real physical process.

[0051] In this embodiment, specifically, based on the preset mapping data, target scattering kernel functions corresponding to at least two target preset photon energy ranges are determined.

[0052] S130: Determine a scatter correction image based on the initial projection image and each target scatter kernel function.

[0053] In an optional embodiment, determining a scatter correction image based on the initial projection image and each target scatter kernel function includes: performing a convolution operation on the initial projection image based on each target scatter kernel function to obtain a convolution projection image, and determining a scatter correction image based on each convolution projection image. Specifically, performing a weighted superposition operation on each convolution projection image to obtain a scatter correction image.

[0054] In another optional embodiment, a scatter correction image is determined based on the initial projection image and each target scatter kernel function, including: performing convolution operations on the initial projection image based on each target scatter kernel function to obtain a convolution projection image, and determining an initial correction image based on each convolution projection image; and determining a scatter correction image based on the initial correction image and target exposure parameters corresponding to the initial projection image.

[0055] Specifically, a weighted superposition operation is performed on each convolution projection image to obtain an initial correction image, and each pixel value in the initial correction image is multiplied by a target exposure parameter to obtain a scatter correction image. Exemplarily, the target exposure parameter includes but is not limited to a target exposure time, a target exposure intensity, a target voltage, a target current, or a target rotation speed, etc.

[0056] The advantage of such a setting is that, in this embodiment, each preset scattering kernel function in the preset mapping data is determined based on a unit exposure parameter. Exemplarily, the unit exposure parameter includes, but is not limited to, a unit exposure duration, a unit exposure intensity, a unit voltage, a unit current, or a unit rotation speed, etc. Therefore, the initial correction image obtained based on the initial projection image and each target scattering kernel function is a correction image based on the unit exposure parameter. However, the initial projection image may not use the unit exposure parameter when it is collected. Therefore, due to the inconsistency of the exposure parameters, there is still an image error between the initial correction image and the scattering correction image. This embodiment improves the image quality of the scattering correction image by taking into account the influence of the target exposure parameters on the basis of the initial correction image.

[0057] S140: Perform a correction operation on the initial projection image based on the scatter correction image to obtain a target projection image.

[0058] Exemplarily, assuming that the scatter correction image is represented by I' and the initial projection image is represented by I0, the target projection image I=I0-I'.

[0059] The technical solution of this embodiment adopts a photon counting detector to determine an initial projection image based on at least two target imaging parameter data, determine a target scattering kernel function corresponding to each target imaging parameter data based on preset mapping data that characterizes a mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function, determine a scattering correction image based on the initial projection image and each target scattering kernel function, perform a correction operation on the initial projection image based on the scattering correction image, and obtain a target projection image, thereby solving the problem that a traditional scattering correction method is not suitable for a photon counting detector, reducing the difficulty of upgrading the detector, and improving the image quality of the target projection image.

[0060] Embodiment 2

[0061] Figure 3 This is a flow chart of a scatter correction method provided by Embodiment 2 of the present invention. This embodiment further refines the "preset mapping data" in the above embodiment. Figure 3 As shown, the method includes:

[0062] S210, obtaining an energy spectrum distribution diagram corresponding to the photon counting detector, and performing a segmentation operation on the energy spectrum distribution diagram based on at least two preset photon energy segments to obtain at least two energy spectrum interval data.

[0063] Specifically, the energy spectrum distribution diagram can be used to characterize the relationship between the preset photon energy and the number of photons. In an optional embodiment, obtaining the energy spectrum distribution diagram corresponding to the photon counting detector includes: based on at least two preset photon energies, obtaining the attenuation rates corresponding to the photon counting detector and at least two reference phantoms respectively; wherein the thickness of each reference phantom is different; for each reference phantom, based on at least two attenuation rates corresponding to the current reference phantom, constructing an attenuation rate equation; based on each attenuation rate equation, determining the energy spectrum distribution diagram corresponding to the photon counting detector.

[0064] Specifically, for each reference phantom, based on at least two preset photon energies, a photon counting detector is used to scan the current reference phantom respectively to obtain at least two attenuation rates corresponding to the current reference phantom.

[0065] Among them, exemplary, the decay rate equation satisfies the formula:

[0066]

[0067] Among them, x i represents the i-th reference motif, μ ρ represents the mass attenuation coefficient, ρ represents the density of the reference model, E j represents the jth preset photon energy, ΔE represents the width of the discrete energy interval, ΔE=E max / (n-1), F(E j ) represents the normalized energy spectrum distribution.

[0068] Specifically, the energy spectrum interval data represents the number of photons corresponding to the corresponding preset photon energy segment in the energy spectrum distribution diagram.

[0069] S220: Generate preset mapping data based on at least one preset exposure parameter and each energy spectrum interval data.

[0070] In an optional embodiment, preset mapping data is generated based on at least one preset exposure parameter and each energy spectrum interval data, including: for each preset exposure parameter, building a Monte Carlo simulation system based on the preset exposure parameter; inputting each energy spectrum interval data into the Monte Carlo simulation system respectively to obtain at least two preset scattering kernel functions as output; generating preset mapping data based on each preset exposure parameter, each preset photon energy segment and each preset scattering kernel function.

[0071] The Monte Carlo simulation system is a simulation system built based on the system environment of the imaging system. The Monte Carlo simulation method is a random simulation method based on probability and statistical theory methods, which can accurately describe the characteristics of things and reflect the real physical process. In this embodiment, the system environment includes the target exposure parameters required to generate the initial projection image.

[0072] In this embodiment, the preset imaging parameter data in the preset mapping data includes preset exposure parameters and preset photon energy segments. Specifically, the preset mapping data includes at least one preset exposure parameter, at least two preset photon energy segments corresponding to each preset exposure parameter, and preset scattering kernel functions corresponding to each preset photon energy segment.

[0073] In an optional embodiment, the preset mapping data includes preset mapping curves corresponding to each preset exposure parameter, and accordingly, the preset mapping data is generated based on each preset exposure parameter, each preset photon energy segment and each preset scattering kernel function, including: for each preset exposure parameter, using a polynomial function, performing a fitting operation on each preset photon energy segment corresponding to the preset exposure parameter and the preset scattering kernel function corresponding to each preset photon energy segment, to obtain a preset mapping curve corresponding to the preset exposure parameter; based on each preset mapping curve, generating the preset mapping data.

[0074] The polynomial function refers to an expression obtained by variables, coefficients, and addition, subtraction, multiplication, and exponentiation (non-negative integer powers) operations between them.

[0075] The advantage of such a setting is that, in the imaging process of the imaging system, there are many combinations of target photon energy segments used in different application scenarios, such as different minimum photon energies, different maximum photon energies, or different energy segment interval lengths of different target photon energy segments, etc. Discrete preset mapping data may not meet the imaging system's requirements for diversity of target photon energy segments. This embodiment obtains preset mapping curves corresponding to each exposure parameter by fitting the preset mapping curve, which can meet the imaging system's requirements for diversity of target photon energy segments, thereby improving the applicability and extensiveness of the scatter correction method.

[0076] S230, acquiring an initial projection image obtained by using a photon counting detector.

[0077] In this embodiment, the initial projection image corresponds to at least two target imaging parameter data, wherein the target imaging parameter data includes a target photon energy range and a preset exposure parameter.

[0078] S240: Determine target scattering kernel functions corresponding to each target imaging parameter data based on preset mapping data.

[0079] S250: Determine a scatter correction image based on the initial projection image and each target scatter kernel function.

[0080] S260: Perform a correction operation on the initial projection image based on the scatter correction image to obtain a target projection image.

[0081] In the case where the target photon energy range is the same but the target exposure parameters are different, the image quality of the target projection image calculated using the same target scattering kernel function is poor. Furthermore, since the correspondence between the target exposure parameter and the target scattering kernel function may not be linear, the degree of improvement in the image quality of the target projection image based on the product operation of the target exposure parameter is relatively limited. The technical solution of this embodiment obtains the energy spectrum distribution map corresponding to the photon counting detector, and performs a segmentation operation on the energy spectrum distribution map based on at least two preset photon energy ranges to obtain at least two energy spectrum interval data, and generates preset mapping data based on at least one preset exposure parameter and each energy spectrum interval data. In this embodiment, the preset imaging parameter data in the preset mapping data includes a preset exposure parameter and a preset photon energy range, which solves the problem of different target scattering kernel functions under different exposure parameters, reduces the calculation error of the scatter correction image, and further improves the image quality of the target projection image.

[0082] Embodiment 3

[0083] Figure 4 This is a schematic diagram of the structure of a scatter correction device provided by Embodiment 3 of the present invention. Figure 4 As shown, the device includes: an initial projection image acquisition module 310, a target scatter kernel function determination module 320, a scatter correction image determination module 330 and a target projection image determination module 340.

[0084] The initial projection image acquisition module 310 is used to acquire an initial projection image obtained by using a photon counting detector; wherein the initial projection image corresponds to at least two target imaging parameter data;

[0085] The target scattering kernel function determination module 320 is used to determine the target scattering kernel function corresponding to each target imaging parameter data based on the preset mapping data; wherein the preset mapping data represents the mapping relationship between at least two preset imaging parameter data and the preset scattering kernel function;

[0086] A scatter correction image determination module 330, configured to determine a scatter correction image based on the initial projection image and each target scatter kernel function;

[0087] The target projection image determination module 340 is used to perform a correction operation on the initial projection image based on the scatter correction image to obtain a target projection image.

[0088] The technical solution of this embodiment adopts a photon counting detector to determine an initial projection image based on at least two target imaging parameter data, determine a target scattering kernel function corresponding to each target imaging parameter data based on preset mapping data that characterizes a mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function, determine a scattering correction image based on the initial projection image and each target scattering kernel function, perform a correction operation on the initial projection image based on the scattering correction image, and obtain a target projection image, thereby solving the problem that a traditional scattering correction method is not suitable for a photon counting detector, reducing the difficulty of upgrading the detector, and improving the image quality of the target projection image.

[0089] Based on the above embodiment, optionally, the target imaging parameter data includes a target photon energy segment, and accordingly, the device further includes:

[0090] A first preset mapping data generating module is used to obtain an energy spectrum distribution diagram corresponding to the photon counting detector, and perform a segmentation operation on the energy spectrum distribution diagram based on at least two preset photon energy segments to obtain at least two energy spectrum interval data;

[0091] Determine the preset scattering kernel functions corresponding to each energy spectrum interval data, and generate preset mapping data based on each preset photon energy segment and each preset scattering kernel function; wherein the preset mapping data represents the mapping relationship between each preset photon energy segment and the preset scattering kernel function.

[0092] Based on the above embodiment, optionally, the scatter correction image determination module 330 is specifically used to:

[0093] Based on each target scattering kernel function, a convolution operation is performed on the initial projection images to obtain convolution projection images, and based on each convolution projection image, an initial correction image is determined;

[0094] A scatter correction image is determined based on the initial correction image and target exposure parameters corresponding to the initial projection image.

[0095] Based on the above embodiment, optionally, the target imaging parameter data includes a target photon energy range and a preset exposure parameter, and accordingly, the device further includes:

[0096] A second preset mapping data generating module is used to obtain an energy spectrum distribution diagram corresponding to the photon counting detector, and perform a segmentation operation on the energy spectrum distribution diagram based on at least two preset photon energy segments to obtain at least two energy spectrum interval data;

[0097] Based on at least one preset exposure parameter and each energy spectrum interval data, preset mapping data is generated; wherein the preset imaging parameter data in the preset mapping data includes preset exposure parameters and preset photon energy segments.

[0098] Based on the above embodiment, optionally, the second preset mapping data generating module includes:

[0099] A Monte Carlo simulation system building unit, used for building a Monte Carlo simulation system based on the preset exposure parameters for each preset exposure parameter;

[0100] A preset scattering kernel function determination unit is used to input the data of each energy spectrum interval into the Monte Carlo simulation system to obtain at least two preset scattering kernel functions as output;

[0101] The preset mapping data generating unit is used to generate preset mapping data based on each preset exposure parameter, each preset photon energy segment and each preset scattering kernel function.

[0102] On the basis of the above embodiment, optionally, the preset mapping data includes preset mapping curves corresponding to the preset exposure parameters respectively, and accordingly, the preset mapping data generating unit is specifically used to:

[0103] For each preset exposure parameter, a polynomial function is used to perform a fitting operation on each preset photon energy segment corresponding to the preset exposure parameter and a preset scattering kernel function corresponding to each preset photon energy segment, so as to obtain a preset mapping curve corresponding to the preset exposure parameter;

[0104] Based on each preset mapping curve, preset mapping data is generated.

[0105] The scatter correction device provided in the embodiment of the present invention can execute the scatter correction method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0106] Embodiment 4

[0107] Figure 5 This is a schematic diagram of the structure of an electronic device provided in Embodiment 4 of the present invention. The electronic device 10 is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0108] like Figure 5As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0109] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0110] The processor 11 may be a variety of general and / or dedicated processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 performs the various methods and processes described above, such as a scatter correction method.

[0111] In some embodiments, the scatter correction method may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the scatter correction method described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to perform the scatter correction method in any other appropriate manner (e.g., by means of firmware).

[0112] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0113] The computer programs for implementing the scatter correction method of the present invention can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program can be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0114] Embodiment 5

[0115] Embodiment 5 of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to execute a scatter correction method, the method comprising:

[0116] Acquire an initial projection image obtained by using a photon counting detector; wherein the initial projection image corresponds to at least two target imaging parameter data;

[0117] Based on the preset mapping data, determining the target scattering kernel function corresponding to each target imaging parameter data respectively; wherein the preset mapping data represents the mapping relationship between at least two preset imaging parameter data and the preset scattering kernel function;

[0118] Determine a scatter correction image based on the initial projection image and the scatter kernel function of each target;

[0119] A correction operation is performed on the initial projection image based on the scatter correction image to obtain a target projection image.

[0120] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0121] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0122] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0123] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0124] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0125] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A scatter correction method, characterized in that: include: Acquire an initial projection image obtained by using a photon counting detector; wherein the initial projection image corresponds to at least two target imaging parameter data; Based on preset mapping data, determining target scattering kernel functions corresponding to each of the target imaging parameter data; wherein the preset mapping data represents a mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function; Determining a scatter correction image based on the initial projection image and each of the target scatter kernel functions; Performing a correction operation on the initial projection image based on the scatter correction image to obtain a target projection image; Wherein, the target imaging parameter data includes a target photon energy segment, and accordingly, the method further includes: Acquire an energy spectrum distribution diagram corresponding to the photon counting detector, and perform a segmentation operation on the energy spectrum distribution diagram based on at least two preset photon energy segments to obtain at least two energy spectrum interval data; Determine the preset scattering kernel functions corresponding to each of the energy spectrum interval data, and generate preset mapping data based on each of the preset photon energy segments and each of the preset scattering kernel functions; wherein the preset mapping data characterizes the mapping relationship between each of the preset photon energy segments and the preset scattering kernel functions.

2. The method according to claim 1, characterized in that: The step of determining a scatter correction image based on the initial projection image and each of the target scatter kernel functions comprises: Based on each of the target scattering kernel functions, respectively perform a convolution operation on the initial projection images to obtain convolution projection images, and based on each of the convolution projection images, determine an initial correction image; A scatter correction image is determined based on the initial correction image and the target exposure parameters corresponding to the initial projection image.

3. The method according to claim 1, characterized in that The target imaging parameter data also includes preset exposure parameters. Accordingly, the determining of preset scattering kernel functions corresponding to each of the energy spectrum interval data includes: For each preset exposure parameter, a Monte Carlo simulation system is built based on the preset exposure parameter; Inputting the energy spectrum interval data into the Monte Carlo simulation system respectively to obtain at least two preset scattering kernel functions as output; Accordingly, the generating of preset mapping data based on each of the preset photon energy segments and each of the preset scattering kernel functions includes: Generate preset mapping data based on each of the preset exposure parameters, each of the preset photon energy ranges, and each of the preset scattering kernel functions; The preset imaging parameter data in the preset mapping data include preset exposure parameters and preset photon energy ranges.

4. The method according to claim 3, characterized in that: The preset mapping data includes preset mapping curves corresponding to the preset exposure parameters. Accordingly, the preset mapping data is generated based on the preset exposure parameters, the preset photon energy ranges and the preset scattering kernel functions, including: For each preset exposure parameter, a polynomial function is used to perform a fitting operation on each of the preset photon energy segments corresponding to the preset exposure parameter and a preset scattering kernel function respectively corresponding to each of the preset photon energy segments, so as to obtain a preset mapping curve corresponding to the preset exposure parameter; Based on each of the preset mapping curves, preset mapping data is generated.

5. The method according to claim 1, characterized in that The obtaining of the energy spectrum distribution diagram corresponding to the photon counting detector comprises: Based on at least two preset photon energies, acquiring attenuation rates corresponding to the photon counting detector and at least two reference phantoms respectively; wherein the thickness of each of the reference phantoms is different; For each reference motif, constructing a decay rate equation based on at least two decay rates corresponding to the current reference motif; Based on each of the attenuation rate equations, an energy spectrum distribution diagram corresponding to the photon counting detector is determined.

6. A scatter correction device, characterized in that: include: An initial projection image acquisition module, used to acquire an initial projection image obtained by using a photon counting detector; wherein the initial projection image corresponds to at least two target imaging parameter data; A target scattering kernel function determination module is used to determine the target scattering kernel function corresponding to each of the target imaging parameter data based on preset mapping data; wherein the preset mapping data represents a mapping relationship between at least two preset imaging parameter data and a preset scattering kernel function; A scatter correction image determination module, configured to determine a scatter correction image based on the initial projection image and each of the target scatter kernel functions; a target projection image determination module, configured to perform a correction operation on the initial projection image based on the scatter correction image to obtain a target projection image; The target imaging parameter data includes a target photon energy segment, and accordingly, the device further includes: A first preset mapping data generating module is used to obtain an energy spectrum distribution diagram corresponding to the photon counting detector, and perform a segmentation operation on the energy spectrum distribution diagram based on at least two preset photon energy segments to obtain at least two energy spectrum interval data; Determine the preset scattering kernel functions corresponding to each of the energy spectrum interval data, and generate preset mapping data based on each of the preset photon energy segments and each of the preset scattering kernel functions; wherein the preset mapping data characterizes the mapping relationship between each of the preset photon energy segments and the preset scattering kernel functions.

7. The scatter correction device according to claim 6, characterized in that: The target imaging parameter data also includes preset exposure parameters, and the device also includes: A second preset mapping data generating module is used to obtain an energy spectrum distribution diagram corresponding to the photon counting detector, and perform a segmentation operation on the energy spectrum distribution diagram based on at least two preset photon energy segments to obtain at least two energy spectrum interval data; Based on at least one preset exposure parameter and each energy spectrum interval data, preset mapping data is generated; wherein the preset imaging parameter data in the preset mapping data includes preset exposure parameters and preset photon energy segments.

8. The scatter correction device according to claim 7, characterized in that: The second preset mapping data generating module includes: A Monte Carlo simulation system building unit, used for building a Monte Carlo simulation system based on the preset exposure parameters for each preset exposure parameter; A preset scattering kernel function determination unit is used to input the data of each energy spectrum interval into the Monte Carlo simulation system to obtain at least two preset scattering kernel functions as output; The preset mapping data generating unit is used to generate preset mapping data based on each preset exposure parameter, each preset photon energy segment and each preset scattering kernel function.

9. An electronic device, characterized in that: The electronic device comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the scatter correction method according to any one of claims 1 to 5.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the scatter correction method according to any one of claims 1 to 5 when executed.

Images