Base material mass attenuation coefficient acquisition method and system, electronic device, and medium

Abstract

The present disclosure provides a base material mass attenuation coefficient acquisition method, system, electronic device and medium. The base material mass attenuation coefficient acquisition method acquires the attenuation characteristic value of a preset calibration phantom containing a target base material with different densities in a target energy interval, and calculates the mass attenuation coefficient of the target base material based on the attenuation characteristic value of the preset calibration phantom and the density of the target base material in different preset calibration phantoms. Based on the accurate mass attenuation coefficient of the target base material obtained by the present disclosure, a material decomposition matrix can be constructed for the to-be-decomposed object, the target image corresponding to the to-be-decomposed object is decomposed based on the material decomposition matrix, and the density image corresponding to the target base material is obtained.

Description

Technical Field

[0001] This disclosure relates to the field of image domain material decomposition technology, and in particular to a method, system, electronic device and medium for obtaining the mass decay coefficient of a base material. Background Technology

[0002] CT technology based on dual-energy or multi-energy spectral imaging can acquire images in different energy ranges, providing richer X-ray attenuation information. By utilizing the characteristic that the attenuation of different substances varies with energy, dual-energy or multi-energy CT imaging can be used to distinguish different substances and reconstruct the density image corresponding to the base material.

[0003] Existing methods for decomposing matter include direct decomposition, projection domain decomposition, and image domain decomposition. The theoretical basis of image domain decomposition is that the mass decay coefficient of any substance can be expressed by the mass decay coefficients of any two other base substances (base substance pairs). Combining the relationship between the linear decay coefficient and the density and mass decay coefficient of the base substances, the following equation holds:

[0004] ;

[0005] in, and These represent the densities of the two base materials, and are independent of the energy of the X-rays. The energy corresponding to the product to be decomposed The linear attenuation coefficient, and These correspond to the two basic substances in the product to be decomposed. The mass decay coefficient.

[0006] In practical applications, calibration phantoms containing the base material are often mixtures, rather than containing only the base material. For example, iodine rods in equivalent tissue materials, or iodine solutions of different concentrations obtained by diluting medical iodine contrast agents, contain background substances such as water or other elements in addition to iodine.

[0007] Therefore, the linear attenuation coefficients obtained from scanning and imaging these calibration phantoms are not entirely generated by the base material. In traditional reconstruction methods, the calculation of the linear attenuation coefficients of calibration phantoms does not adequately distinguish between the target base material and the background material, leading to inaccurate material decomposition matrices and consequently, inaccurate density of the obtained base material. Summary of the Invention

[0008] To address the aforementioned technical problems, this disclosure provides a method, system, electronic device, and medium for obtaining the mass decay coefficient of a base material.

[0009] In a first aspect, this disclosure provides a method for obtaining the mass decay coefficient of a base material, including:

[0010] At least two preset calibration phantoms are obtained; wherein, the preset calibration phantoms include a target base material, and the density of the target base material is different in different preset calibration phantoms;

[0011] Obtain the attenuation characteristic value of each preset calibration phantom corresponding to the target energy range;

[0012] Based on the attenuation characteristic value of the preset calibration model and the density of the target base material, the mass attenuation coefficient of the target base material corresponding to the target energy range is obtained.

[0013] Optionally, the preset calibration phantom also includes background material;

[0014] The step of obtaining the mass decay coefficient of the target base material corresponding to the target energy range further includes:

[0015] A set of target equations is constructed based on the relationship between the attenuation characteristic values ​​of different preset calibration mods and the density of the target base material and the density of the background material; wherein, the attenuation characteristic value is the sum of the linear attenuation coefficient of the target base material and the linear attenuation coefficient of the background material; the linear attenuation coefficient of the target base material is the product of the density of the target base material and the mass attenuation coefficient of the target base material, and the linear attenuation coefficient of the background material is the product of the density of the background material and the mass attenuation coefficient of the background material;

[0016] The mass decay coefficient of the target base material is obtained based on the target equation set.

[0017] Optionally, for different preset calibration phantoms, if the density of the background material is the same,

[0018] The step of obtaining the mass decay coefficient of the target base material corresponding to the target energy range further includes:

[0019] Using the attenuation characteristic values ​​of different preset calibration phantoms and the density of the target base material contained in the preset calibration phantoms, a least-squares linear fit is performed based on the target equation set to obtain a first fitting relationship;

[0020] The mass decay coefficient of the target base material is determined based on the first fitting relationship.

[0021] Optionally, for different preset calibration phantoms, if the density of the background material differs after being diluted according to a preset dilution factor,

[0022] The step of obtaining the mass decay coefficient of the target base material corresponding to the target energy range includes:

[0023] Using the attenuation characteristic values ​​of different preset calibration phantoms, the density of the target base material contained in the preset calibration phantoms, and the preset dilution factor, a second fitting relationship is obtained by performing least squares linear fitting based on the target equation set;

[0024] The mass decay coefficient of the target base material is determined based on the second fitting relationship.

[0025] Optionally, the attenuation characteristic value is a linear attenuation coefficient or a CT value.

[0026] Secondly, this disclosure provides an imaging method, including:

[0027] According to the method for obtaining the mass decay coefficient of the base material described in the first aspect, the mass decay coefficient of the target energy range corresponding to the target base material in the decomposed material is obtained.

[0028] Construct a material decomposition matrix based on the mass decay coefficient of the target base material;

[0029] The target image is decomposed based on the material decomposition matrix to obtain the density image corresponding to the target base material; wherein, the target image is an energy spectrum imaging map of the target energy range corresponding to the material to be decomposed.

[0030] Thirdly, this disclosure provides a system for obtaining the mass decay coefficient of a base material, comprising:

[0031] A phantom acquisition module is used to acquire at least two preset calibration phantoms; wherein, the preset calibration phantoms include a target base material, and the density of the target base material is different in different preset calibration phantoms;

[0032] The feature value acquisition module is used to acquire the attenuation feature value of the target energy range corresponding to the preset calibration model;

[0033] The first attenuation coefficient acquisition module is used to acquire the mass attenuation coefficient of the target base material corresponding to the target energy range based on the attenuation characteristic value of the preset calibration model and the density of the target base material.

[0034] Optionally, the preset calibration phantom also includes background material;

[0035] The first attenuation coefficient acquisition module is used to construct a set of target equations based on the relationship between the attenuation characteristic values ​​of different preset calibration models and the density of the target base material and the density of the background material; wherein, the attenuation characteristic value is the sum of the linear attenuation coefficient of the target base material and the linear attenuation coefficient of the background material; the linear attenuation coefficient of the target base material is the product of the density of the target base material and the mass attenuation coefficient of the target base material, and the linear attenuation coefficient of the background material is the product of the density of the background material and the mass attenuation coefficient of the background material; and the mass attenuation coefficient of the target base material is obtained based on the set of target equations.

[0036] Optionally, for different preset calibration phantoms, if the density of the background material is the same,

[0037] The first attenuation coefficient acquisition module is specifically used to use the attenuation characteristic values ​​of different preset calibration phantoms and the density of the target base material contained in the preset calibration phantoms to perform least squares linear fitting based on the target equation set to obtain a first fitting relationship; and to determine the mass attenuation coefficient of the target base material based on the first fitting relationship.

[0038] Optionally, for different preset calibration phantoms, if the density of the background material differs after being diluted according to a preset dilution factor,

[0039] The first attenuation coefficient acquisition module is specifically used to use the attenuation characteristic values ​​of different preset calibration phantoms, the density of the target base material contained in the preset calibration phantoms, and the preset dilution factor to perform least squares linear fitting based on the target equation set to obtain a second fitting relationship; and to determine the mass attenuation coefficient of the target base material based on the second fitting relationship.

[0040] Optionally, the attenuation characteristic value is a linear attenuation coefficient or a CT value.

[0041] Fourthly, this disclosure provides an imaging system, comprising:

[0042] The second attenuation coefficient acquisition module is used to acquire the mass attenuation coefficient of the target base material in the decomposed material corresponding to the target energy range according to the base material mass attenuation coefficient acquisition system described in the third aspect.

[0043] A decomposition matrix construction module is used to construct a material decomposition matrix based on the mass decay coefficient of the target base material.

[0044] The material decomposition module is used to decompose the target image based on the material decomposition matrix to obtain the density image corresponding to the target base material; wherein, the target image is an energy spectrum imaging map of the target energy range corresponding to the material to be decomposed.

[0045] Fifthly, this disclosure provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the method for obtaining the mass decay coefficient of the matrix material as described in the first aspect or the imaging method as described in the second aspect.

[0046] In a sixth aspect, this disclosure provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, it implements the method for obtaining the mass decay coefficient of the substrate as described in the first aspect or the imaging method as described in the second aspect.

[0047] The positive advancements of this disclosure are as follows: This disclosure provides a method, system, electronic device, and medium for obtaining the mass decay coefficient of a base material. It involves acquiring the decay characteristic values ​​of preset calibration phantoms containing target base materials of different densities within a target energy range. Based on the decay characteristic values ​​of the preset calibration phantoms and the densities of the target base material in different preset calibration phantoms, the mass decay coefficient of the target base material is calculated. Based on the accurate mass decay coefficient of the target base material, a material decomposition matrix is ​​constructed for the material to be decomposed. The target image corresponding to the material to be decomposed is then decomposed based on the material decomposition matrix to obtain the density image corresponding to the target base material. In particular, this disclosure utilizes multiple preset calibration phantoms containing target base materials of different densities for calibration and optimization, which can reduce the deviation caused by beam hardening. Attached Figure Description

[0048] Figure 1 A schematic flowchart illustrating the method for obtaining the mass decay coefficient of the base material provided in this embodiment of the disclosure;

[0049] Figure 2 This is a schematic diagram of step S103 in the method for obtaining the mass decay coefficient of the base material provided in the embodiments of this disclosure.

[0050] Figure 3 A schematic flowchart of the imaging method provided in the embodiments of this disclosure;

[0051] Figure 4 A schematic diagram of the modules of the system for obtaining the mass decay coefficient of the base material provided in this embodiment of the disclosure;

[0052] Figure 5 A schematic diagram of the imaging system provided in the embodiments of this disclosure;

[0053] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this disclosure. Detailed Implementation

[0054] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments described herein.

[0055] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this embodiment, unless otherwise stated, "a plurality of" means two or more.

[0056] Figure 1 An embodiment of a method for obtaining the mass decay coefficient of a base material provided in this disclosure is shown.

[0057] See Figure 1 The method for obtaining the mass decay coefficient of the base material includes:

[0058] S101. Obtain at least two preset calibration phantoms; wherein, the preset calibration phantoms include a target base material, and the density of the target base material is different in different preset calibration phantoms;

[0059] S102. Obtain the attenuation characteristic value of each preset calibration phantom corresponding to the target energy range;

[0060] S103. Based on the attenuation characteristic value of the preset calibration model and the density of the target base material, obtain the mass attenuation coefficient of the target base material corresponding to the target energy range.

[0061] Specifically, in order to obtain the true density image of the target matrix material in the decomposed material under the target energy range, a preset calibration phantom containing target matrix materials of different densities is first prepared, that is, at least two preset calibration phantoms are required. Then, the decay characteristic values ​​of the preset calibration phantoms under the target energy range are obtained respectively, and the mass decay coefficient of the target matrix material is calculated based on the decay characteristic values ​​of the preset calibration phantoms and the density of the target matrix material in different preset calibration phantoms.

[0062] The attenuation characteristic value can be either a linear attenuation coefficient or a CT value. For convenience, the CT value of a preset calibration phantom can be obtained directly, or the linear attenuation coefficient can be calculated based on the obtained CT value according to the conversion relationship between the CT value of the preset calibration phantom and the linear attenuation coefficient, or the CT value can be calculated based on the obtained linear attenuation coefficient.

[0063] Specifically, the conversion relationship between CT value and linear attenuation coefficient is as follows:

[0064] ;

[0065] in, The linear attenuation coefficient of the preset calibration model.

[0066] See Figure 2If the preset calibration phantom also includes background material, step S103 specifically includes:

[0067] S1031. Construct a set of target equations based on the relationship between the attenuation characteristic values ​​of different preset calibration models and the density of the target base material and the density of the background material.

[0068] S1032. Obtain the mass decay coefficient of the target base material based on the target equation set.

[0069] Wherein, the attenuation characteristic value is the sum of the linear attenuation coefficient of the target base material and the linear attenuation coefficient of the background material; the linear attenuation coefficient of the target base material is the product of the density of the target base material and the mass attenuation coefficient of the target base material, and the linear attenuation coefficient of the background material is the product of the density of the background material and the mass attenuation coefficient of the background material.

[0070] Specifically, assuming there are n preset calibration phantoms containing target matrix materials of different densities, the decay characteristic values ​​of the 1st to nth preset calibration phantoms in the target energy range are respectively The densities of the target matrix materials contained in the first to nth preset calibration phantoms are respectively And the densities of the background material contained in the first to nth preset calibration phantoms are respectively Accordingly, the objective equations are:

[0071]

[0072] in, This represents the mass decay coefficient of the target base material within the target energy range. This represents the mass decay coefficient of the background material within the target energy range.

[0073] Given that the densities of the target base material and the background material in the pre-calibrated phantom are both known, the mass decay coefficient of the target base material can be obtained by directly solving the target equation system. Mass decay coefficient of background material .

[0074] In other embodiments, when attenuation characteristic values ​​of three or more preset calibration phantoms are obtained, the optimal solution of the overdetermined equation can be obtained using the following least squares equation:

[0075] ;

[0076] in, For the first The decay characteristic values ​​of a preset calibration phantom within the target energy range. For the first The density of the target base material in a preset calibration phantom For the first The density of the background material in a preset calibration phantom.

[0077] The mass decay coefficient of the target matrix material obtained by using this method Mass decay coefficient of background material This can reduce the influence of nonlinear attenuation changes in matrix materials of different densities caused by beam hardening.

[0078] When the target base material in the pre-calibrated phantom is known, but the density of the background material is unknown, the pre-calibrated phantom can be diluted with the background material solvent, and a least-squares linear fit can be performed based on the known quantities. The mass decay coefficient of the target base material can then be determined based on the obtained fit relationship. .

[0079] In some embodiments, the preset calibration phantom comprising the target base material and the background material is known to be a solution, wherein the density of the target base material in the solution is [insert density here]. The solvent is the background substance, but the density of the background substance is... Unknown, the solution is diluted n-1 times using the same solvent, and combined with the undiluted solution, a total of n solutions with different densities of the target base material but the same density of the background material can be obtained as n preset calibration models.

[0080] Therefore, for different preset calibration phantoms, if the density of the background material is the same, step S1032 specifically includes:

[0081] Using the attenuation characteristic values ​​of different preset calibration phantoms and the density of the target base material contained in the preset calibration phantoms, a least-squares linear fit is performed based on the target equation system to obtain the first fitting relationship;

[0082] The mass decay coefficient of the target base material is determined based on the first fitting relationship.

[0083] The first fitting relationship is:

[0084] .

[0085] According to the first fitting relationship, Mass decay coefficient of the target base material , The linear decay coefficient of the background material is the mass decay coefficient of the background material. Density relative to background material The product of.

[0086] Furthermore, if the decay characteristics of the background material can be considered similar to those of water, the mass decay coefficient of water in the target energy range can be used instead of the mass decay coefficient of the background material. For example, the mass decay coefficient of water in the target energy range can be queried from a database as... ,calculate and The density of the background material can be obtained by taking the quotient. .

[0087] In other embodiments, the pre-defined calibration phantom comprising the target base material and the background material is known to be a solution, wherein the density of the target base material in the solution is [insert density here]. The solvent is the background substance, but the density of the background substance is... The solution is unknown. It is diluted with water n-1 times. Combined with the undiluted solution, a total of n solutions with different densities of target base material and background material can be obtained as n preset calibration models.

[0088] The density of the target base substance in the diluted solution can be based on its density before dilution. With the Dilution factor The calculation yielded the result. Similarly, the density of the background substance in the diluted solution can be obtained using the density before dilution. With each dilution factor To express.

[0089] Specifically, if the density of water is 1, then the density of the background substance in the diluted solution can be expressed as:

[0090] .

[0091] Therefore, for different preset calibration phantoms, if the density of the background material differs after being diluted according to a preset dilution factor, step S1032 specifically includes:

[0092] Using the attenuation characteristic values ​​of different preset calibration phantoms, the density of the target base material contained in the preset calibration phantoms, and the preset dilution factor, a least-squares linear fit is performed based on the target equation system to obtain the second fitting relationship;

[0093] The mass decay coefficient of the target base material is determined based on the second fitting relationship.

[0094] The second fitting relationship is:

[0095] .

[0096] Based on the second fitting relationship and the density of background substances in the diluted solution It can be seen that, Mass decay coefficient of the target base material , , The mass decay coefficient of the background material .

[0097] Using the method for obtaining the mass decay coefficient of the target base material provided in the above embodiments, an accurate mass decay coefficient of the target base material can be obtained. Using the accurate mass decay coefficient of the target base material, a material decomposition matrix can be constructed for the material to be decomposed. Based on the material decomposition matrix, the target image corresponding to the material to be decomposed can be decomposed to obtain the density image corresponding to the target base material.

[0098] Figure 3 An embodiment of an imaging method provided in this disclosure is shown.

[0099] See Figure 3 The imaging method includes:

[0100] S301. Based on the above method for obtaining the mass decay coefficient of the base material, obtain the mass decay coefficient of the target energy range corresponding to the target base material in the decomposed material.

[0101] S302. Construct a material decomposition matrix based on the mass decay coefficient of the target base material;

[0102] S303. Decompose the target image based on the material decomposition matrix to obtain the density image corresponding to the target base material; wherein, the target image is the energy spectrum imaging map of the target energy range corresponding to the material to be decomposed.

[0103] Taking dual-energy spectroscopy as an example, energy-dispersive CT imaging obtains the linear decay coefficient of the substance to be decomposed in two energy ranges. and and the mass decay coefficient of the first target base material in the first energy range. The mass decay coefficient of the first target base material in the second energy range The mass decay coefficient of the second target base material in the first energy range The mass decay coefficient of the second target base material in the second energy range Then, the density of the base material can be solved using the following material decomposition matrix:

[0104] ;

[0105] in, The density of the first target base material. This represents the density of the second target base material.

[0106] Taking multi-energy imaging as an example, energy spectrum CT imaging obtains the linear decay coefficient of the substance to be decomposed in N energy ranges. to and the mass decay coefficient of different target base materials in the first energy range. to The mass decay coefficient of different target base materials in the second energy range to Then, the density of the base material can be solved using the following material decomposition matrix:

[0107] .

[0108] in, to These represent the densities of different target base materials.

[0109] Figure 4 An embodiment of a system for obtaining the mass decay coefficient of a base material provided in this disclosure is shown.

[0110] See Figure 4 The system for obtaining the mass decay coefficient of the base material includes:

[0111] The phantom acquisition module 401 is used to acquire at least two preset calibration phantoms; wherein, the preset calibration phantoms include a target base material, and the density of the target base material is different in different preset calibration phantoms;

[0112] The feature value acquisition module 402 is used to acquire the attenuation feature value of the target energy range corresponding to the preset calibration model;

[0113] The first attenuation coefficient acquisition module 403 is used to acquire the mass attenuation coefficient of the target base material corresponding to the target energy range based on the attenuation characteristic value of the preset calibration model and the density of the target base material.

[0114] Specifically, in order to obtain the true density image of the target matrix material in the decomposed material under the target energy range, a preset calibration phantom containing target matrix materials of different densities is first prepared, that is, at least two preset calibration phantoms are required. Then, the decay characteristic values ​​of the preset calibration phantoms under the target energy range are obtained respectively, and the mass decay coefficient of the target matrix material is calculated based on the decay characteristic values ​​of the preset calibration phantoms and the density of the target matrix material in different preset calibration phantoms.

[0115] The attenuation characteristic value can be either a linear attenuation coefficient or a CT value. For convenience, the CT value of a preset calibration phantom can be obtained directly, or the linear attenuation coefficient can be calculated based on the obtained CT value according to the conversion relationship between the CT value of the preset calibration phantom and the linear attenuation coefficient, or the CT value can be calculated based on the obtained linear attenuation coefficient.

[0116] Specifically, the conversion relationship between CT value and linear attenuation coefficient is as follows:

[0117] ;

[0118] in, The linear attenuation coefficient of the preset calibration model.

[0119] The first attenuation coefficient acquisition module 403 is specifically used to construct a set of target equations based on the relationship between the attenuation characteristic values ​​of different preset calibration models and the density of the target base material and the density of the background material; and to obtain the mass attenuation coefficient of the target base material based on the set of target equations.

[0120] Wherein, the attenuation characteristic value is the sum of the linear attenuation coefficient of the target base material and the linear attenuation coefficient of the background material; the linear attenuation coefficient of the target base material is the product of the density of the target base material and the mass attenuation coefficient of the target base material, and the linear attenuation coefficient of the background material is the product of the density of the background material and the mass attenuation coefficient of the background material.

[0121] Specifically, assuming there are n preset calibration phantoms containing target matrix materials of different densities, the decay characteristic values ​​of the 1st to nth preset calibration phantoms in the target energy range are respectively The densities of the target matrix materials contained in the first to nth preset calibration phantoms are respectively And the densities of the background material contained in the first to nth preset calibration phantoms are respectively Accordingly, the objective equations are:

[0122]

[0123] in, This represents the mass decay coefficient of the target base material within the target energy range. This represents the mass decay coefficient of the background material within the target energy range.

[0124] Given that the densities of the target base material and the background material in the pre-calibrated phantom are both known, the mass decay coefficient of the target base material can be obtained by directly solving the target equation system. Mass decay coefficient of background material .

[0125] In other embodiments, when attenuation characteristic values ​​of three or more preset calibration phantoms are obtained, the optimal solution of the overdetermined equation can be obtained using the following least squares equation:

[0126] ;

[0127] in, For the first The decay characteristic values ​​of a preset calibration phantom within the target energy range. For the first The density of the target base material in a preset calibration phantom For the first The density of the background material in a preset calibration phantom.

[0128] The mass decay coefficient of the target matrix material obtained by using this method Mass decay coefficient of background material This can reduce the influence of nonlinear attenuation changes in matrix materials of different densities caused by beam hardening.

[0129] When the target base material in the pre-calibrated phantom is known, but the density of the background material is unknown, the pre-calibrated phantom can be diluted with the background material solvent, and a least-squares linear fit can be performed based on the known quantities. The mass decay coefficient of the target base material can then be determined based on the obtained fit relationship. .

[0130] In some embodiments, the preset calibration phantom comprising the target base material and the background material is known to be a solution, wherein the density of the target base material in the solution is [insert density here]. The solvent is the background substance, but the density of the background substance is... Unknown, the solution is diluted n-1 times using the same solvent, and combined with the undiluted solution, a total of n solutions with different densities of the target base material but the same density of the background material can be obtained as n preset calibration models.

[0131] Therefore, for different preset calibration phantoms, if the density of the background material is the same, the first attenuation coefficient acquisition module 403 is specifically used to use the attenuation characteristic values ​​of different preset calibration phantoms and the density of the target base material contained in the preset calibration phantoms to perform least squares linear fitting based on the target equation set to obtain the first fitting relationship; and to determine the mass attenuation coefficient of the target base material based on the first fitting relationship.

[0132] The first fitting relationship is:

[0133] .

[0134] According to the first fitting relationship, Mass decay coefficient of the target base material , The linear decay coefficient of the background material is the mass decay coefficient of the background material. Density relative to background material The product of.

[0135] Furthermore, if the decay characteristics of the background material can be considered similar to those of water, the mass decay coefficient of water in the target energy range can be used instead of the mass decay coefficient of the background material. For example, the mass decay coefficient of water in the target energy range can be queried from a database as... ,calculate and The density of the background material can be obtained by taking the quotient. .

[0136] In other embodiments, the pre-defined calibration phantom comprising the target base material and the background material is known to be a solution, wherein the density of the target base material in the solution is [insert density here]. The solvent is the background substance, but the density of the background substance is... The solution is unknown. It is diluted with water n-1 times. Combined with the undiluted solution, a total of n solutions with different densities of target base material and background material can be obtained as n preset calibration models.

[0137] The density of the target base substance in the diluted solution can be based on its density before dilution. With the Dilution factor The calculation yielded the result. Similarly, the density of the background substance in the diluted solution can be obtained using the density before dilution. With each dilution factor To express.

[0138] Specifically, if the density of water is 1, then the density of the background substance in the diluted solution can be expressed as:

[0139] .

[0140] Therefore, for different preset calibration phantoms, if the density of the background material is different after being diluted according to the preset dilution factor, the first attenuation coefficient acquisition module 403 is specifically used to use the attenuation characteristic value of different preset calibration phantoms, the density of the target base material contained in the preset calibration phantom and the preset dilution factor, to perform least squares linear fitting based on the target equation set to obtain the second fitting relationship; and to determine the mass attenuation coefficient of the target base material based on the second fitting relationship.

[0141] The second fitting relationship is:

[0142] .

[0143] Based on the second fitting relationship and the density of background substances in the diluted solution It can be seen that, Mass decay coefficient of the target base material , , The mass decay coefficient of the background material .

[0144] Using the matrix material mass decay coefficient acquisition system provided in the above embodiments, the accurate mass decay coefficient of the target matrix material can be obtained. Using the accurate mass decay coefficient of the target matrix material, a material decomposition matrix can be constructed for the material to be decomposed. Based on the material decomposition matrix, the target image corresponding to the material to be decomposed is decomposed to obtain the density image corresponding to the target matrix material.

[0145] Figure 5 An embodiment of an imaging system provided in this disclosure is shown.

[0146] See Figure 5 The imaging system includes:

[0147] The second attenuation coefficient acquisition module 501 is used to acquire the mass attenuation coefficient of the target base material in the decomposed material corresponding to the target energy range according to the above-mentioned base material mass attenuation coefficient acquisition system.

[0148] Decomposition matrix construction module 502 is used to construct a material decomposition matrix based on the mass decay coefficient of the target base material;

[0149] The material decomposition module 503 is used to decompose the target image based on the material decomposition matrix to obtain the density image corresponding to the target base material; wherein, the target image is the energy spectrum imaging map of the target energy range corresponding to the material to be decomposed.

[0150] Taking dual-energy spectroscopy as an example, energy-dispersive CT imaging obtains the linear decay coefficient of the substance to be decomposed in two energy ranges. and and the mass decay coefficient of the first target base material in the first energy range. The mass decay coefficient of the first target base material in the second energy range The mass decay coefficient of the second target base material in the first energy range The mass decay coefficient of the second target base material in the second energy range Then, the density of the base material can be solved using the following material decomposition matrix:

[0151] ;

[0152] in, The density of the first target base material. This represents the density of the second target base material.

[0153] Taking multi-energy imaging as an example, energy spectrum CT imaging obtains the linear decay coefficient of the substance to be decomposed in N energy ranges. to and the mass decay coefficient of different target base materials in the first energy range. to The mass decay coefficient of different target base materials in the second energy range to Then, the density of the base material can be solved using the following material decomposition matrix:

[0154] .

[0155] in, to These represent the densities of different target base materials.

[0156] Figure 6 The structure of one of the electronic devices disclosed herein is shown. The electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the above-described method for obtaining the mass attenuation coefficient of the substrate or the imaging method. Figure 6 The electronic device 60 shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments disclosed herein.

[0157] like Figure 6 As shown, the electronic device 60 can also be represented in the form of a general computing device, such as a server device. The components of the electronic device 60 may include, but are not limited to: at least one processor 61, at least one memory 62, and a bus 63 connecting different system components (including memory 62 and processor 61).

[0158] Bus 63 includes a data bus, an address bus, and a control bus.

[0159] The memory 62 may include volatile memory, such as random access memory (RAM) 621 and / or cache memory 622, and may further include read-only memory (ROM) 623.

[0160] The memory 62 may also include a program / utility 625 having a set (at least one) of program modules 624, including but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of these examples may include an implementation of a network environment.

[0161] The processor 61 executes various functional applications and data processing by running computer programs stored in the memory 62, such as the method for obtaining the mass decay coefficient of the matrix material or the imaging method described above in this disclosure.

[0162] Electronic device 60 can also communicate with one or more external devices 64 (e.g., keyboard, pointing device, etc.). This communication can be performed via input / output (I / O) interface 65. Furthermore, the model-generating device 60 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 66. Figure 6 As shown, network adapter 66 communicates with other modules of the model-generated device 60 via bus 63. It should be understood that, although not shown in the figure, other hardware and / or software modules can be used in conjunction with the model-generated device 60, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (disk array) systems, tape drives, and data backup storage systems.

[0163] It should be noted that although several units / modules or sub-units / modules of the electronic device have been mentioned in the detailed description above, this division is merely exemplary and not mandatory. In fact, according to embodiments of this disclosure, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided and embodied by multiple units / modules.

[0164] This disclosure also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described method for obtaining the mass attenuation coefficient of the matrix material or the imaging method.

[0165] The readable storage medium may be more specifically adopted, including but not limited to: portable disk, hard disk, random access memory, read-only memory, erasable programmable read-only memory, optical storage device, magnetic storage device, or any suitable combination thereof.

[0166] In possible implementations, this disclosure can also be implemented as a program product comprising program code, which, when the program product is run on a terminal device, is used to cause the terminal device to execute the above-described method for obtaining the mass attenuation coefficient of the matrix material or the imaging method.

[0167] The program code for executing this disclosure can be written using any combination of one or more programming languages. The program code can be executed entirely on a user device, partially on a user device, as a standalone software package, partially on a user device and partially on a remote device, or entirely on a remote device.

[0168] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A method for obtaining the mass decay coefficient of a base material, characterized in that, The method for obtaining the mass decay coefficient of the base material includes: At least two preset calibration phantoms are obtained; wherein, the preset calibration phantoms include a target base material, and the density of the target base material is different in different preset calibration phantoms; Obtain the attenuation characteristic value of each preset calibration phantom corresponding to the target energy range; Based on the attenuation characteristic value of the preset calibration model and the density of the target base material, the mass attenuation coefficient of the target base material corresponding to the target energy range is obtained; The preset calibration phantom also includes background material; The step of obtaining the mass decay coefficient of the target base material corresponding to the target energy range further includes: A set of target equations is constructed based on the relationship between the attenuation characteristic values ​​of different preset calibration mods and the density of the target base material and the density of the background material. The mass decay coefficient of the target base material is obtained based on the target equation set; For different preset calibration phantoms, if the density of the background material is the same, The step of obtaining the mass decay coefficient of the target base material based on the target equation set further includes: Using the attenuation characteristic values ​​of different preset calibration phantoms and the density of the target base material contained in the preset calibration phantoms, a least-squares linear fit is performed based on the target equation set to obtain a first fitting relationship; The mass decay coefficient of the target base material is determined based on the first fitting relationship; For different preset calibration phantoms, if the density of the background material differs after being diluted according to a preset dilution factor... The step of obtaining the mass decay coefficient of the target base material based on the target equation set includes: Using the attenuation characteristic values ​​of different preset calibration phantoms, the density of the target base material contained in the preset calibration phantoms, and the preset dilution factor, a second fitting relationship is obtained by performing least squares linear fitting based on the target equation set; The mass decay coefficient of the target base material is determined based on the second fitting relationship.

2. The method for obtaining the mass decay coefficient of the base material according to claim 1, characterized in that, The attenuation characteristic value is the sum of the linear attenuation coefficient of the target base material and the linear attenuation coefficient of the background material; the linear attenuation coefficient of the target base material is the product of the density of the target base material and the mass attenuation coefficient of the target base material, and the linear attenuation coefficient of the background material is the product of the density of the background material and the mass attenuation coefficient of the background material.

3. The method for obtaining the mass decay coefficient of the base material according to claim 1, characterized in that, The attenuation characteristic value is a linear attenuation coefficient, or the attenuation characteristic value is calculated based on the CT value.

4. An imaging method, characterized in that, The imaging method includes: According to any one of claims 1-3, the method for obtaining the mass decay coefficient of the base material is used to obtain the mass decay coefficient of the target energy range of the target base material in the decomposed material. Construct a material decomposition matrix based on the mass decay coefficient of the target base material; The target image is decomposed based on the material decomposition matrix to obtain the density image corresponding to the target base material; wherein, the target image is an energy spectrum imaging map of the target energy range corresponding to the material to be decomposed.

5. A system for obtaining the mass decay coefficient of a base material, characterized in that, The system for obtaining the mass decay coefficient of the base material includes: A phantom acquisition module is used to acquire at least two preset calibration phantoms; wherein, the preset calibration phantoms include a target base material, and the density of the target base material is different in different preset calibration phantoms; The feature value acquisition module is used to acquire the attenuation feature value of the target energy range corresponding to the preset calibration model; The first attenuation coefficient acquisition module is used to acquire the mass attenuation coefficient of the target base material corresponding to the target energy range based on the attenuation characteristic value of the preset calibration model and the density of the target base material. The preset calibration phantom also includes background material; The first attenuation coefficient acquisition module is also used to construct a set of target equations based on the relationship between the attenuation characteristic values ​​of different preset calibration models and the density of the target base material and the density of the background material; The first attenuation coefficient acquisition module is also used to acquire the mass attenuation coefficient of the target base material based on the target equation set; For different preset calibration phantoms, if the density of the background material is the same, The first attenuation coefficient acquisition module is specifically used to use the attenuation characteristic values ​​of different preset calibration phantoms and the density of the target base material contained in the preset calibration phantoms to perform least squares linear fitting based on the target equation system to obtain a first fitting relationship; and to determine the mass attenuation coefficient of the target base material based on the first fitting relationship. For different preset calibration phantoms, if the density of the background material differs after being diluted according to a preset dilution factor... The first attenuation coefficient acquisition module is specifically used to use the attenuation characteristic values ​​of different preset calibration phantoms, the density of the target base material contained in the preset calibration phantoms, and the preset dilution factor to perform least squares linear fitting based on the target equation set to obtain a second fitting relationship; and to determine the mass attenuation coefficient of the target base material based on the second fitting relationship.

6. The system for obtaining the mass decay coefficient of the base material according to claim 5, characterized in that, The attenuation characteristic value is the sum of the linear attenuation coefficient of the target base material and the linear attenuation coefficient of the background material; the linear attenuation coefficient of the target base material is the product of the density of the target base material and the mass attenuation coefficient of the target base material, and the linear attenuation coefficient of the background material is the product of the density of the background material and the mass attenuation coefficient of the background material.

7. The system for obtaining the mass decay coefficient of the base material according to claim 5, characterized in that, The attenuation characteristic value is a linear attenuation coefficient, or the attenuation characteristic value is calculated based on the CT value.

8. An imaging system, characterized in that, The imaging system includes: The second attenuation coefficient acquisition module is used to acquire the mass attenuation coefficient of the target base material in the target energy range in the decomposed material according to any one of claims 5 to 7. A decomposition matrix construction module is used to construct a material decomposition matrix based on the mass decay coefficient of the target base material. The material decomposition module is used to decompose the target image based on the material decomposition matrix to obtain the density image corresponding to the target base material; wherein, the target image is an energy spectrum imaging map of the target energy range corresponding to the material to be decomposed.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method for obtaining the mass decay coefficient of the matrix material as described in any one of claims 1-3, or implements the imaging method as described in claim 4.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for obtaining the mass decay coefficient of the base material as described in any one of claims 1-3, or implements the imaging method as described in claim 4.

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