Sensitivity measurement methods, systems, electronic devices, and storage media for long-axis PET systems

Abstract

The application provides a long-axis PET system sensitivity measurement method, system, electronic equipment and storage medium. The long-axis PET system sensitivity measurement method comprises the following steps: dividing a long-axis PET system into a plurality of units along the axis of the long-axis PET system, moving a line source to a specific position for measurement in sequence to obtain a group of initial data; sleeving a sleeve with different thicknesses on the line source, repeating the above steps to obtain a plurality of groups of initial data; correcting each group of initial data, and obtaining the sensitivity of each effective combination of the line source at the specific position based on the corrected data and the parameter information of the line source; and accumulating the sensitivities of all effective combinations to obtain the total sensitivity of the long-axis PET system. In this way, the length of the line source required for measurement is reduced, and the influence of the bubbles and unevenness generated by filling the long line source on the measurement result of the sensitivity is avoided, the operability of the sensitivity measurement of the long-axis PET system is improved, and the accuracy of the measurement result is improved.

Description

Technical Field

[0001] This invention relates to the field of medical technology, and in particular to a method, system, electronic device, and storage medium for measuring the sensitivity of a long-axis PET system. Background Technology

[0002] Sensitivity, as one of the most important system performance parameters in positron emission tomography (PET), is closely related to the injection dose during patient scanning, the patient's scan time, the selection of reconstruction parameters, and the volume of patients in the hospital, and directly affects the image quality obtained by the final PET system scan. Therefore, it is crucial to obtain the sensitivity parameters of the PET system quickly, easily, and accurately.

[0003] Currently, the axial length range of PET systems on the market includes traditional axial lengths of 15cm to 35cm, as well as whole-body imaging systems with an axial field of view of 70cm to 200cm that have been developed and put into the market in recent years. For traditional systems with an axial field of view of 15cm to 35cm, measurements are typically performed using the standard method (NEMA NU 2) published by the National Electrical Manufacturers Association (NEMA). This method uses a 70cm long wire source to measure sensitivity within the entire axial field of view, thus providing a comprehensive sensitivity distribution for the PET system. However, for the whole-body imaging systems developed in recent years with an axial field of view of 70cm to 200cm, the traditional 70cm wire source method in NEMA NU 2 can only measure the sensitivity distribution curve within a portion of the axial field of view and cannot represent the true sensitivity of the entire PET system. Some researchers have used wire sources longer than 200cm for measurement, but the excessive length makes wire source preparation and filling difficult, leading to air bubbles and unevenness. Furthermore, in actual experiments, the wire source needs to be repeatedly removed from the PET system to be fitted with aluminum tubes of varying thicknesses and lengths up to 200cm, complicating the experimental process and introducing some error into the results. Summary of the Invention

[0004] The purpose of this invention is to provide a method, system, electronic device, and storage medium for measuring the sensitivity of long-axis PET systems, in order to solve the problem that existing measurement methods cannot accurately measure the sensitivity of long-axis PET systems (axial field of view range of 70cm to 200cm).

[0005] To achieve the above objectives, the present invention provides a method for measuring the sensitivity of a long-axis PET system, comprising:

[0006] The long-axis PET system is divided into several units along its own axis, and the line source is moved to a specific position in sequence for measurement to obtain a set of initial data;

[0007] Sleeves of different thicknesses are fitted over the wire source, and the above steps are repeated to obtain multiple sets of the initial data;

[0008] Each set of initial data is corrected, and the sensitivity of each effective combination of the line source at the specific position is obtained based on the corrected data and the parameter information of the line source.

[0009] The total sensitivity of the long-axis PET system is obtained by summing the sensitivities of all the effective combinations.

[0010] Optionally, the specific location includes: the axial center position of each unit and the connection position between two adjacent units.

[0011] Optionally, the line source has at least one of the valid combinations at any of the specific locations, and the initial data includes: valid data for all the valid combinations of the line source at the specific locations.

[0012] Optionally, the correction of each set of the initial data includes:

[0013] Based on the time of the line source activity measurement, the start time of the acquisition, and the half-life of the radioactive source, the initial data is corrected to obtain the corrected count value.

[0014] Optionally, obtaining the sensitivity of the line source at each effective combination at the specific location based on the corrected data and the parameter information of the line source includes:

[0015] Based on the count value and the thickness of the sleeve, a count value without attenuation is obtained;

[0016] The sensitivity of the effective combination is obtained based on the count value without attenuation and the line source activity of the line source.

[0017] Optionally, the thickness of the sleeve can be changed by increasing or decreasing the number of sleeve layers.

[0018] To achieve the above objectives, the present invention also provides a long-axis PET system sensitivity measurement system for applying the long-axis PET system sensitivity measurement method described above, comprising: a measurement component and a data acquisition device;

[0019] The measuring assembly includes a wire source and a sleeve, the sleeve being fitted over the outside of the wire source, and the measuring assembly being movable along the axial direction of the long-axis PET system;

[0020] The data acquisition device is used to acquire data from the long-axis PET system when the measuring component moves to a specific position;

[0021] The overall sensitivity of the long-axis PET system is determined based on the collected data and the parameter information of the line source.

[0022] Optionally, the axial length of any unit is less than the length of the line source, and the axial length of the long-axis PET system is greater than the length of the line source.

[0023] To achieve the above objectives, the present invention also provides an electronic device, comprising:

[0024] Memory, which stores computer programs;

[0025] The processor, which is communicatively connected to the memory, is used to execute the long-axis PET system sensitivity measurement method as described above when the computer program is invoked;

[0026] A display, communicatively connected to the memory and the processor, is used to display a GUI interface related to the long-axis PET system sensitivity measurement method.

[0027] To achieve the above objectives, the present invention also provides a storage medium storing a computer program, which, when executed by a processor, implements the long-axis PET system sensitivity measurement method as described above.

[0028] In summary, the sensitivity measurement method, system, electronic device, and storage medium for a long-axis PET system provided by this invention include: dividing the long-axis PET system into several units along its own axis; sequentially moving the line source to a specific position for measurement to obtain a set of initial data; placing sleeves of different thicknesses around the line source and repeating the above steps to obtain multiple sets of initial data; correcting each set of initial data and obtaining the sensitivity of each effective combination of line sources at a specific position based on the corrected data and the parameter information of the line source; and summing the sensitivities of all effective combinations to obtain the total sensitivity of the long-axis PET system. Compared with existing sensitivity measurement methods, this application has the following advantages:

[0029] The long-axis PET system is divided into multiple units along its own axis, and the initial data at a specific position of each unit is measured separately. The sensitivity of the entire long-axis PET system is differentiated into the sum of the sensitivities of the effective combination of each specific position. This reduces the length of the line source required for measurement, and avoids the influence of air bubbles and inhomogeneities caused by injecting a longer line source on the sensitivity measurement results. This improves the operability of sensitivity measurement of the long-axis PET system and also improves the accuracy of the measurement results. Attached Figure Description

[0030] Figure 1 A schematic flowchart illustrating the sensitivity measurement method for a long-axis PET system provided in an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of a line source at a first specific position provided in an embodiment of the present invention;

[0032] Figure 3 This is a schematic diagram of a line source at a second specific location provided in an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of a line source at a third specific location provided in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram illustrating the effective combinations that a line source can collect at any specific location, as provided in an embodiment of the present invention.

[0035] Figure 6 A block diagram of the electronic device provided in an embodiment of the present invention;

[0036] The explanations of the reference numerals in the accompanying drawings are as follows:

[0037] 1-Measuring component; 2-Long-axis PET system; 3-Processor; 4-Memory; 5-Display; 6-Communication interface; 7-Communication bus. Detailed Implementation

[0038] To make the objectives, advantages, and features of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clarify the explanation of the embodiments of this invention. Furthermore, the structures shown in the drawings are often part of the actual structures. In particular, different figures may emphasize different aspects and may sometimes use different scales.

[0039] As used herein, the singular forms “a,” “an,” and “the” include plural objects; the term “or” is generally used to mean “and / or”; the term “a number” is generally used to mean “at least one”; and the term “at least two” is generally used to mean “two or more”. Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include one or at least two of that feature. “One end” and “the other end,” as well as “proximal end” and “distal end,” generally refer to two corresponding parts, including not only endpoints. The terms “installed,” “connected,” and “joined” should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two elements or the interaction between two elements. Furthermore, as used in this specification, the phrase "one element is disposed on another element" generally only indicates that there is a connection, coupling, cooperation, or transmission relationship between the two elements, and the connection, coupling, cooperation, or transmission between the two elements can be direct or indirect through an intermediate element. It should not be construed as indicating or implying a spatial positional relationship between the two elements, i.e., one element can be located arbitrarily inside, outside, above, below, or to the side of another element, unless otherwise explicitly stated. The terms "above," "below," "top," and "bottom" generally refer to relative positional relationships arranged according to the direction of gravity; the terms "vertical" or "vertical direction" generally refer to the direction of gravity, which is generally perpendicular to the ground; "horizontal" or "horizontal plane direction" generally refers to a direction parallel to the ground. Those skilled in the art can understand the specific meaning of the above terms in this specification according to the specific circumstances.

[0040] The purpose of this invention is to provide a method, system, electronic device, and storage medium for measuring the sensitivity of long-axis PET systems, in order to solve the problem that existing measurement methods cannot accurately measure the sensitivity of long-axis PET systems (axial field of view range of 70cm to 200cm).

[0041] The following explanation is based on the accompanying drawings.

[0042] The inventors have discovered that as PET systems have gradually evolved into whole-body imaging systems with an axial field of view covering 700mm to 2000mm (hereinafter referred to as long-axis PET systems), existing measurement methods cannot accurately measure the sensitivity of long-axis PET systems. As those skilled in the art will understand, sensitivity is a core parameter of a PET system; a system with higher sensitivity can obtain more counts and suppress noise under the same acquisition conditions, thereby improving image quality. The sensitivity of a PET system is expressed as the count rate per second at which true coincidence events are detected under a given source intensity; that is, with a fixed radiation source activity, the measured count represents the system's sensitivity. However, existing methods for measuring sensitivity using a 700mm line source can only measure the sensitivity distribution curve within a portion of the axial field of view in a long-axis PET system, and cannot represent the overall true sensitivity of the long-axis PET system. If a line source longer than 2000mm is used for measurement, the excessive length makes it difficult to inject and measure, reducing the accuracy of the measurement results. Therefore, this application provides a method for measuring the sensitivity of a long-axis PET system using a standard-length line source (e.g., 700mm), which improves the operability of the measurement process and also enhances the accuracy of the measurement results.

[0043] Please refer to Figures 1 to 5 This invention provides a method for measuring the sensitivity of a long-axis PET system, comprising:

[0044] Step S1: Divide the long-axis PET system 2 into several units (detector rings) along its own axis, move the line source to a specific position in sequence to perform measurement, and obtain a set of initial data;

[0045] Step S2: Place sleeves of different thicknesses around the wire source, and repeat step S1 above to obtain multiple sets of initial data;

[0046] Step S3: Correct each set of initial data, and based on the corrected data and the parameter information of the line source, obtain the sensitivity of each effective combination of the line source at a specific position;

[0047] Step S4: Sum the sensitivities of all valid combinations to obtain the total sensitivity of the long-axis PET system 2.

[0048] As those skilled in the art will understand, during PET system imaging, the emitted positrons generate a pair of gamma photons through annihilation radiation. A large amount of material must be placed around the radiation source to ensure the occurrence of annihilation radiation. However, during the measurement of the PET system's sensitivity, the material surrounding the radiation source also attenuates the generated gamma photons, thus affecting the measurement. To achieve attenuation-free measurement, continuous measurements need to be performed on a uniform line source surrounded by absorbing material, and the sensitivity without absorbing material needs to be extrapolated. In an optional embodiment, the line source is a plastic tube filled with water mixed with radioactive material and sealed at both ends (its length can be 700 mm ± 5 mm as specified in the NEMA NU 2 standard); the sleeve is the aforementioned absorbing material, which can be an aluminum tube with a certain thickness and a fixed attenuation coefficient; the initial data includes, but is not limited to, PET imaging data.

[0049] In another embodiment, the line source (700 mm in length) is driven by a motion device to reciprocate at a constant speed within the axial field of view of the long-axis PET system 2 in a direction parallel to the axial direction of the long-axis PET system 2 (i.e., moving at a constant speed from one end of the long-axis PET system 2 to the other end, and then moving at a constant speed from the other end back to the initial end), and the corresponding data is collected by a data acquisition device. In the above embodiment, since the line source is in a continuous motion state, the collected data may contain invalid data that can only describe a part of the axial field of view of the long-axis PET system 2. To ensure that the collected data can cover the entire axial field of view of the long-axis PET system 2, multiple uniform reciprocating movements are usually required to form a set of valid data (valid data is data that can completely describe the entire axial field of view of the long-axis PET system 2). When the sleeve thickness is changed or the number of sleeve layers is increased or decreased, multiple uniform reciprocating movements need to be repeated to obtain multiple sets of valid data. Since the measurement time is long, the influence of the half-life of the radioactive source on the measurement results must be considered. Therefore, when using the method in the above embodiment for measurement, time slices need to be divided to correct for the influence of the half-life of the radioactive source. In the measurement method of this application, the long-axis PET system 2 is divided into multiple units (i.e., multiple detector rings), and the line source is moved to specific positions (e.g., the axial center of each unit and the connection between two adjacent units). The initial data collected are all valid data (i.e., the initial data collected can characterize the sensitivity of the axial field of view of the unit or adjacent units). Each measurement only requires moving the line source with the sleeve from one side of the long-axis PET system 2 to the other. When the sleeve thickness is changed or the number of sleeve layers is increased or decreased, only unidirectional movement is required. There is no need for reciprocating movement, and there is no requirement for the speed of movement. The operator can directly place the line source in a specific position. Compared with the above embodiments, the measurement method of this application can reduce the measurement time, thereby reducing the impact of the half-life of the radioactive source on the measurement data (this does not mean that this application does not need to consider the impact of the half-life of the radioactive source, but only that compared with the method of the above embodiments, this application does not need to take the half-life of the radioactive source as the primary consideration, and only needs to process it slightly during the calibration process), thus improving the measurement efficiency; at the same time, the initial data collected by this application are all valid data, improving the data processing efficiency; in addition, this application reduces the difficulty of measurement and data processing by converting the sensitivity of the long-axis PET system 2 into the sum of the sensitivity of the effective combination of each specific position, and also improves the accuracy of the measurement results.

[0050] Specifically, in Figures 2 to 5In the illustrated example, the long-axis PET system 2 is divided into eight units along its own axis (left-right direction in the figure), named U0 to U7 from left to right. The line source moves along the axis of the long-axis PET system 2 from U0 to U7, and measurements are taken at specific locations to obtain initial data. Optionally, the specific locations include: the axial center position of each unit and the connection position between two adjacent units; furthermore, the line source has at least one valid combination at any specific location, and the initial data includes: valid data of all valid combinations of the line source at the specific locations. It should be noted that the long-axis PET system 2 is a component composed of multiple annular units (detector rings), each annular unit consisting of multiple crystals, to... Figure 2 For example, when the line source moves to the axial center position of cell U0, the only valid data that can be obtained is the combined data emitted from and received by the crystal located in cell U0. That is, when the line source is located at the axial center position of cell U0, the valid combination is U0-U0, and the initial data obtained is denoted as Data00_i, where i is the number of sleeve layers; Figure 3 For example, when the line source moves to the connection position between units U0 and U1, the valid data that can be obtained are the combined data emitted from the crystal located in unit U0 and received by the crystal located in unit U1, and the combined data emitted from the crystal located in unit U1 and received by the crystal located in unit U0. That is, when the line source is located at the connection position between units U0 and U1, the valid combination is U0-U1 and U1-U0, and the obtained initial data is denoted as Data01_i and Data10_i. Similarly, the line source is moved to 15 specific positions in sequence, and the corresponding initial data is obtained, as shown in Table 1. Figure 5 The initial data table is shown.

[0051] Table 1 Initial Data Table

[0052]

[0053]

[0054] In some other embodiments, the operator may also divide the long-axis PET system 2 into other suitable numbers of units according to its axial length. However, it is necessary to ensure that the axial length of each unit is less than the length of the line source to guarantee that the line source covers each unit, thereby improving the accuracy of the measurement results of the sensitivity of each effective combination. At the same time, in order to facilitate the identification of direction, this embodiment divides such as U0-U1 and U1-U0 into two effective combinations. In other embodiments, such as U0-U1 and U1-U0 can also be a single effective combination. Those skilled in the art can configure the division of the long-axis PET system 2 and the setting of effective combinations according to actual needs. This embodiment is not limited in this regard. With this configuration, this application divides the long-axis PET system 2 into multiple units along its own axis and measures the initial data at a specific position of each unit. This differentiates the sensitivity of the entire long-axis PET system 2 into the sum of the effective combinations of sensitivities at each specific position, reducing the length of the line source required for measurement. At the same time, it avoids the influence of air bubbles and unevenness generated by injecting a longer line source on the sensitivity measurement results, improving the operability of sensitivity measurement of the long-axis PET system 2 and also improving the accuracy of the measurement results.

[0055] As an optional embodiment, each set of initial data is corrected, including:

[0056] Step S3-1: Based on the time of activity measurement of the line source, the start time of acquisition, and the half-life of the radioactive source, correct the initial data to obtain the corrected count value.

[0057] It should be noted that for each initial data point obtained from each measurement, the decay of the radioactive source needs to be corrected for the count rate using Formula 1:

[0058]

[0059] Wherein, X and Y represent the unit numbers of the division, which are 1 to 7 in this embodiment;

[0060] i represents the number of sleeve layers, which is 1 to 5 in this embodiment;

[0061] j represents the number of recombined slices;

[0062] T cal This refers to the moment when the activity of the line source is measured in the activity meter;

[0063] T XY,i The starting acquisition time for obtaining data corresponding to different numbers of casing layers for different effective combinations;

[0064] T 1 / 2 The half-life of the radioactive source;

[0065] R XY,i,jIt involves reorganizing the original data into the corresponding data for each slice;

[0066] R XY,CORR,i,j This is the count value after decay correction corresponding to the radioactive source.

[0067] As those skilled in the art will understand, a radioactive source has a half-life, so the intensity of the radioactive source will be different when measured at different times. Therefore, in the process of measuring the sensitivity of the long-axis PET system 2, it is necessary to divide the measurement time into segments based on the half-life to generate time slices, and finally obtain decay-corrected data, which further improves the accuracy of the measurement results.

[0068] In an alternative embodiment, the sensitivity of each effective combination of the line source at a specific location is obtained based on the corrected data and the parameter information of the line source, including:

[0069] Step S3-2: Based on the count value and the thickness of the sleeve, obtain the count value without attenuation;

[0070] It should be noted that after decay correction, the total value is obtained by summing the count values. Then, a regression method is used to fit Equation 2 to obtain the count value without decay.

[0071] R XY,CORR,j =R XY,CORR,0 ·exp(-μ M ·2·X j ) Formula 2

[0072] Among them, R XY,CORR,0 With μ M It is an unknown;

[0073] X j This is the cumulative sleeve thickness;

[0074] R XY,CORR,0 This is a count value with no decay.

[0075] μ M This is the metal attenuation coefficient, which can be appropriately modified to compensate for a small amount of scattered radiation.

[0076] The same procedure is used to measure the sensitivity at a radial distance of 10 cm from the center of the tomographic imaging device.

[0077] Step S3-3: Based on the attenuated count value and the line source activity, obtain the sensitivity of the effective combination.

[0078] It should be noted that the sensitivity of each effective combination is calculated using Formula 3:

[0079]

[0080] Among them, S XY,tot The sensitivity for any valid combination;

[0081] A cal For line source activity.

[0082] Finally, S represents all valid combinations of X and Y. XY,tot The total sensitivity of the long-axis PET system 2 can be obtained by summing the values.

[0083] In one embodiment, the thickness of the sheath is changed by increasing or decreasing the number of sheath layers. It should be noted that in this embodiment, the sheath has 5 layers. Each time a layer is added or removed, the line source needs to be moved sequentially along the axial direction of the long-axis PET system 2 to obtain corresponding initial data. Based on the line source count rate when different sheath thicknesses are set, the sensitivity of the long-axis PET system 2 without sheaths is derived. Those skilled in the art will understand that the thickness of the 5 sheath layers can be consistent or inconsistent, and they can flexibly configure the sheath thickness according to actual conditions.

[0084] In another embodiment, the present invention also provides a long-axis PET system sensitivity measurement system for applying the above-described long-axis PET system 2 sensitivity measurement method, comprising: a measuring component 1 and a data acquisition device (not shown in the figure); the measuring component 1 includes a line source and a sleeve, the sleeve being fitted over the outside of the line source, and the measuring component 1 being movable along the axial direction of the long-axis PET system 2; the data acquisition device is used to acquire data from the long-axis PET system 2 when the measuring component 1 moves to a specific position; the total sensitivity of the long-axis PET system 2 is determined based on the acquired data and the parameter information of the line source. It should be noted that, in an optional embodiment, the long-axis PET system 2 sensitivity measurement system may further include a motion device (not shown in the figure), the measuring component 1 is placed on the motion device, and the measuring component 1 moves in a direction parallel to the axial direction of the long-axis PET system 2 under the drive of the motion device; the data acquisition device may be a cylindrical component fitted over the outside of the measuring component 1 to receive radiation, wherein the central axis of the data acquisition device and the central axis of the measuring component 1 need to be collinear. Figures 2 to 4 In the illustrated example, the measuring component 1 moves along the central axis of the long axis PET system 2. In some other embodiments, the measuring component 1 may also move along an axis that is offset from the central axis.

[0085] The following section explains the operating principle of the long-axis PET system sensitivity measurement method using the long-axis PET system sensitivity measurement system as an example. Figures 2 to 4Taking the measurement component 1 and long-axis PET system 2 as an example, the measurement component 1 is movable along the axial direction of the long-axis PET system 2. When the measurement component 1 moves to a specific position, the acquisition device acquires the effective combinations at the corresponding position. After the measurement component 1 moves from one end of the long-axis PET system 2 to the other end, the number of sleeve layers is increased or decreased, and then it moves along the axial direction of the long-axis PET system 2 until sufficient initial data is acquired. Then, based on the acquired initial data and the corresponding line source parameter information, the initial data is corrected to obtain the corrected count value, and the count value without decay is derived accordingly. Then, the sensitivity of each effective combination is obtained. Finally, the sensitivities of each effective combination are summed to obtain the total sensitivity of the long-axis PET system 2.

[0086] In an optional embodiment, the axial length of any unit is less than the length of the wire source, and the axial length of the long-axis PET system 2 is greater than the length of the wire source. It should be noted that in this embodiment, the long-axis PET system 2 is divided into 8 equal units along the axial direction. In other examples, the long-axis PET system 2 can also be divided into units of different lengths along the axial direction. However, it is important to note that the axial length of any unit must be less than the length of the wire source so that the wire source can completely cover any unit, ensuring the integrity of the data collected for each effective combination. Simultaneously, the axial length of the long-axis PET system 2 being greater than the length of the wire source effectively reduces the length of the wire source, avoiding the impact of air bubbles and unevenness generated by injecting a longer wire source on the sensitivity measurement results. This improves the operability of sensitivity measurement of the long-axis PET system 2 and also improves the accuracy of the measurement results.

[0087] In another embodiment, the present invention also provides an electronic device, comprising: a memory 4 storing a computer program; a processor 3 communicatively connected to the memory 4, used to execute the above-described long-axis PET system sensitivity measurement method when the computer program is invoked; and a display 5 communicatively connected to the memory 4 and the processor 3, used to display a GUI interface related to the long-axis PET system sensitivity measurement method. Since the above-described electronic device is used to execute any of the above-described long-axis PET system sensitivity measurement methods, it can effectively reduce the length of the line source required for measurement, while avoiding the influence of air bubbles and unevenness generated by pouring a longer line source on the sensitivity measurement results, thus improving the operability of sensitivity measurement of the long-axis PET system 2 and also improving the accuracy of the measurement results.

[0088] like Figure 6As shown, the electronic device also includes a communication interface 6 and a communication bus 7, where the processor 3, communication interface 6, and memory 4 communicate with each other via the communication bus 7. The communication bus 7 can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus 7 can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, only one thick line is used in the figure, but this does not indicate that there is only one bus or one type of bus. The communication interface 6 is used for communication between the aforementioned electronic device and other devices.

[0089] The processor 3 referred to in this invention can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor. The processor 3 is the control center of the electronic device, connecting various parts of the entire electronic device through various interfaces and lines.

[0090] The memory 4 can be used to store computer programs. The processor 3 implements various functions of the electronic device by running or executing the computer programs stored in the memory 4 and calling the data stored in the memory 4.

[0091] Memory 4 may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), Synchlink, direct memory bus RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and direct memory bus dynamic RAM (RDRAM), etc.

[0092] In another embodiment, the present invention also provides a storage medium storing a computer program, which, when executed by processor 3, implements the above-described long-axis PET system sensitivity measurement method. Since the storage medium is used to execute any of the above-described long-axis PET system sensitivity measurement methods, it effectively reduces the length of the line source required for measurement, while avoiding the influence of air bubbles and unevenness generated by pouring a longer line source on the sensitivity measurement results. This improves the operability of sensitivity measurement of the long-axis PET system 2 and also improves the accuracy of the measurement results.

[0093] The readable storage medium of embodiments of the present invention can be any combination of one or more computer-readable media. The readable medium can be a computer-readable signal medium or a computer-readable storage medium. Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: electrical connections having one or more wires, portable computer hard disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, apparatus, or device.

[0094] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of transmitting, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to wireless, wireline, optical fiber, RF, etc., or any suitable combination thereof.

[0095] In summary, in the long-axis PET system sensitivity measurement method, system, electronic device, and storage medium provided in the embodiments of the present invention, the long-axis PET system sensitivity measurement method includes: dividing the long-axis PET system into several units along its own axis, sequentially moving the line source to a specific position for measurement, and obtaining a set of initial data; placing sleeves of different thicknesses around the line source, repeating the above steps, and obtaining multiple sets of initial data; correcting each set of initial data, and obtaining the sensitivity of each effective combination of the line source at a specific position based on the corrected data and the parameter information of the line source; and accumulating the sensitivity of all effective combinations to obtain the total sensitivity of the long-axis PET system.

[0096] This configuration, by dividing the long-axis PET system into multiple units along its own axis and measuring the initial data at specific locations in each unit, differentiates the sensitivity of the entire long-axis PET system into the sum of the effective combinations of sensitivities at each specific location. This reduces the length of the line source required for measurement and avoids the influence of air bubbles and inhomogeneities caused by injecting longer line sources on the sensitivity measurement results. This improves the operability of sensitivity measurement of the long-axis PET system and also improves the accuracy of the measurement results.

[0097] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A method of sensitivity measurement for a long-axis PET system, characterized by, The method comprises the following steps: Divide the long-axis PET system along its own axis into several units, and move the line source to a specific position for measurement in sequence to obtain a group of initial data; Wrap a sleeve of different thickness around the line source, repeat the above steps, and obtain a plurality of groups of initial data; Correct each group of initial data, and obtain the sensitivity of each effective combination of the line source at the specific position based on the corrected data and the parameter information of the line source; Add up the sensitivities of all the effective combinations to obtain the total sensitivity of the long-axis PET system; The axial length of any unit is less than the length of the line source; The specific positions include the axial center position of each unit and the connecting position between adjacent two units.

2. The long-axis PET system sensitivity measurement method of claim 1, wherein, The line source has at least one effective combination at any specific position, and the initial data includes the effective data of all the effective combinations of the line source at the specific position.

3. The long-axis PET system sensitivity measurement method of claim 1, wherein, The correction of each group of initial data comprises the following steps: Correct the initial data based on the time of measuring the activity of the line source, the starting acquisition time, and the half-life of the radioactive source to obtain the corrected count value.

4. The long-axis PET system sensitivity measurement method of claim 3, wherein, The sensitivity of each effective combination of the line source at the specific position based on the corrected data and the parameter information of the line source comprises the following steps: Based on the count value and the thickness of the sleeve, obtain the non-attenuated count value; Based on the non-attenuated count value and the line source activity of the line source, obtain the sensitivity of the effective combination.

5. The long-axis PET system sensitivity measurement method of claim 1, wherein, The thickness of the sleeve can be changed by increasing or decreasing the number of layers of the sleeve.

6. A long-axis PET system sensitivity measurement system for applying the long-axis PET system sensitivity measurement method according to any one of claims 1 to 5, characterized by The method comprises the following steps: A measurement assembly and an acquisition device; The measurement assembly comprises a line source and a sleeve, the sleeve is wrapped outside the line source, and the measurement assembly is movable along the axis of the long-axis PET system; The acquisition device is used to collect data of the long-axis PET system when the measurement assembly moves to a specific position; Determine the total sensitivity of the long-axis PET system based on the collected data and the parameter information of the line source.

7. The long-axis PET system sensitivity measurement system of claim 6, wherein, The axial length of the long-axis PET system is greater than the length of the line source.

8. An electronic device, comprising: The method comprises the following steps: A memory stores a computer program; A processor is communicatively connected with the memory, and is used to execute the long-axis PET system sensitivity measurement method of any one of claims 1-5 when the computer program is invoked; A display is communicatively connected with the memory and the processor, and is used to display a GUI interaction interface related to the long-axis PET system sensitivity measurement method.

9. A storage medium storing a computer program, characterized by The computer program is executed by the processor to realize the long-axis PET system sensitivity measurement method of any one of claims 1-5.

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