Fat quantitative measurement method, device and equipment based on multi-frequency microwave excitation and medium

Abstract

The invention relates to the field of thermoacoustic imaging, and particularly discloses a fat quantitative measurement method, device and equipment based on multi-frequency microwave excitation and a medium, the method comprises the following steps: sequentially irradiating a body part with microwave pulses of multiple frequencies, and obtaining thermal ultrasonic signals generated by the body part corresponding to the microwave pulses of multiple frequencies; constructing a relation model between the sound pressure response and the fat content of the body part related to the microwave pulses of the multiple frequencies; according to the generated thermal ultrasonic signal, the fat content of the body part is determined through inversion of the relation model. According to the method, a data model between frequency response and tissue absorption characteristics is established, the absorption rate of the body part to microwaves with different frequencies is highly related to the fatty degeneration degree, and a multi-frequency excitation mechanism is introduced, so that the recognition capability and the measurement accuracy of the body part are improved, and the quantitative detection of the fat content of the body part is realized.

Description

Technical Field

[0001] This invention relates to the field of thermoacoustic imaging, and more particularly to a method, apparatus, device, and medium for quantitative measurement of fat based on multi-frequency microwave excitation. Background Technology

[0002] Fatty liver disease and atherosclerosis are diseases caused by abnormal lipid metabolism, leading to fat accumulation in parts of the body such as the liver and carotid arteries. These conditions are reversible and often present with no obvious symptoms in their early stages. Early screening for non-alcoholic fatty liver disease (NAFLD) and early-stage atherosclerosis before the formation of vulnerable plaques is crucial for halting disease progression and implementing effective interventions.

[0003] Currently, the main imaging technologies used in clinical practice for detecting fat deposits in body parts include ultrasound imaging, computed tomography (CT), and magnetic resonance imaging (MRI). Ultrasound imaging is inexpensive, non-invasive, and radiation-free, but it struggles to quantitatively measure fat content. CT imaging offers superior imaging resolution but carries the risk of ionizing radiation and is expensive, making it unsuitable for long-term follow-up. MRI can achieve high-precision measurement of fat proportions, but the equipment is expensive, the imaging time is long, and the operation is complex, hindering its widespread adoption as a routine screening tool. Therefore, there is an urgent need for a low-cost, radiation-free method for quantitatively measuring fat deposits in body parts that is suitable for routine use. Summary of the Invention

[0004] This invention discloses a method, device, computer equipment, and storage medium for quantitative measurement of fat based on multi-frequency microwave excitation. In order to achieve quantitative assessment of fat content in body parts, a data model between frequency response and tissue absorption characteristics is established. The absorption rate of microwaves at different frequencies in body parts is highly correlated with the degree of fat degeneration. By introducing a multi-frequency excitation mechanism, the ability to identify body parts and the accuracy of measurement are improved. It can sensitively reflect the changes in the absorption rate of microwaves in body parts. Compared with traditional single-frequency excitation methods, it has significant advantages in signal stability, noise resistance, and imaging accuracy.

[0005] The first aspect of this invention discloses a method for quantitative measurement of fat based on multi-frequency microwave excitation, the method comprising:

[0006] A method for quantitative measurement of fat based on multi-frequency microwave excitation, the method comprising:

[0007] Multiple microwave pulses of different frequencies are sequentially irradiated onto body parts to obtain thermo-ultrasound signals generated by microwave pulses of different frequencies corresponding to different body parts.

[0008] Construct a model relating the acoustic pressure response of body parts to microwave pulses of multiple frequencies to fat content;

[0009] The fat content of body parts is determined by inversion from the relational model based on the generated thermo-ultrasound signals.

[0010] Optionally, the step of sequentially irradiating a body part with microwave pulses of multiple frequencies to obtain thermo-ultrasound signals generated by microwave pulses of multiple frequencies corresponding to the body part includes:

[0011] Multiple microwave pulses of different frequencies are irradiated onto the body parts in a preset time sequence. During each irradiation of the body parts with a microwave pulse of a certain frequency, the thermo-ultrasound signal generated by the microwave pulse of the current frequency is simultaneously collected from the body parts.

[0012] Optionally, the construction of the model relating the sound pressure response of body parts to microwave pulses of multiple frequencies to fat content includes:

[0013] A first-order relationship model was constructed between the acoustic pressure response of a body part and its electrical conductivity under microwave pulse irradiation at multiple frequencies.

[0014] A second relationship model was constructed between the electrical conductivity of body parts and the fat content of body parts under microwave pulse irradiation at multiple frequencies.

[0015] Based on the first and second relational models, a model is constructed to represent the relationship between the sound pressure response of body parts to microwave pulses of multiple frequencies and fat content.

[0016] Optionally, before constructing the first relationship model between the sound pressure response of a body part and the electrical conductivity of the body part under microwave pulse irradiation at multiple frequencies, the method further includes:

[0017] A first correlation model was constructed between the energy absorbed by a body part per unit volume under microwave pulse irradiation at multiple frequencies and the electrical conductivity of the body part.

[0018] A second correlation model was constructed between the temperature rise of body parts under microwave pulse irradiation at multiple frequencies and the energy absorbed by the body parts per unit volume of microwave pulses.

[0019] A third correlation model was constructed between the sound pressure response of body parts and the temperature rise of body parts under microwave pulse irradiation at multiple frequencies.

[0020] The first relationship model between the acoustic pressure response and electrical conductivity of a body part under microwave pulse irradiation at multiple frequencies includes:

[0021] Based on the first correlation model, the second correlation model, and the third correlation model, a first relationship model is constructed between the sound pressure response of a body part and the electrical conductivity of the body part under microwave pulse irradiation at multiple frequencies.

[0022] Optionally, the construction of a second relationship model between the electrical conductivity of a body part and its fat content under microwave pulse irradiation at multiple frequencies includes:

[0023] To obtain data on the effect of fatty degeneration on the electrical conductivity of body parts under microwave pulse irradiation at multiple frequencies;

[0024] A power-law distribution model was used to model the influence data, resulting in a second relationship model between the electrical conductivity of body parts and the fat content of body parts.

[0025] Optionally, the step of constructing a relationship model between the sound pressure response of body parts to microwave pulses of multiple frequencies and fat content based on the first relationship model and the second relationship model includes:

[0026] Using the electrical conductivity of body parts as an intermediate parameter, and integrating the first and second relationship models, a relationship model is constructed between the fused sound pressure obtained from body part detection and the sound pressure response of the body part to microwave pulses of multiple frequencies, and the fat content; the relationship model is as follows:

[0027] ;

[0028] in, This indicates the fused sound pressure obtained from detection of body parts. Indicates the first The sound pressure response of a microwave pulse at a certain frequency to a part of the body. Indicates the first The influence coefficient of microwave pulses of a certain frequency on the conductivity of a body part, where N represents the number of different frequencies of microwave pulses irradiating the body part. This indicates the fat content of a body part.

[0029] Optionally, the step of constructing a relationship model between the sound pressure response of body parts and fat content for microwave pulses of multiple frequencies based on the first relationship model and the second relationship model further includes:

[0030] By irradiating a phantom with a known fat content with microwave pulses of multiple frequencies, thermosonic signals of the phantom corresponding to the microwave pulses of multiple frequencies were obtained.

[0031] The acoustic pressure response was obtained by least-squares fitting of the thermosonic signal. and influence coefficient .

[0032] A second aspect of the present invention discloses a fat quantification measurement device based on multi-frequency microwave excitation, the device comprising:

[0033] A microwave irradiation module is used to sequentially irradiate multiple frequencies of microwave pulses onto body parts.

[0034] Thermo-ultrasound signal acquisition module is used to acquire thermo-ultrasound signals generated by microwave pulses of multiple frequencies corresponding to different body parts;

[0035] The model building module is used to build models of the relationship between sound pressure response of body parts and fat content for microwave pulses of multiple frequencies.

[0036] The inversion module is used to determine the fat content of body parts by inverting from the relational model based on the generated thermo-ultrasound signals.

[0037] A third aspect of the present invention discloses a computer device comprising a processor and a memory for storing a processor-executable program, wherein when the processor executes the program stored in the memory, it implements the above-described method for quantitative measurement of fat.

[0038] A fourth aspect of the present invention discloses a computer-readable storage medium storing a program that, when executed by a processor, implements the above-described method for quantitative measurement of fat.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] This invention utilizes microwave thermoacoustic imaging technology, combining the high selectivity of microwave absorption in tissues with the high resolution of ultrasound. It enables imaging of thermo-ultrasound signals caused by differences in microwave absorption within biological tissues. The principle is as follows: after microwave irradiation of biological tissue, polar molecules within the tissue rotate, and charged ions move in a directional manner. These ions collide with surrounding molecules, converting into heat energy, which then triggers instantaneous thermal expansion and generates an ultrasound signal. Adipose tissue, primarily composed of nonpolar triglycerides, does not readily absorb microwave energy. As the proportion of fat in a body part increases, its conductivity gradually decreases, leading to a corresponding reduction in microwave absorption and a weakening of the generated thermo-ultrasound signal. By detecting these changes in the thermo-ultrasound signal, quantitative detection of fat content in body parts can be achieved. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a flowchart illustrating the quantitative measurement method for fat based on multi-frequency microwave excitation according to Embodiment 1 of the present invention.

[0043] Figure 2 This is a structural block diagram of the fat quantitative measurement device based on multi-frequency microwave excitation according to Embodiment 2 of the present invention.

[0044] Figure 3 This is a diagram showing the equipment composition of the fat quantitative measurement device based on multi-frequency microwave excitation in Embodiment 3 of the present invention.

[0045] Figure 4 These are thermo-ultrasound images of bionics with different proportions of fat content in Example 3 of the present invention.

[0046] Figure 5 This is a structural block diagram of the computer device according to Embodiment 4 of the present invention. Detailed Implementation

[0047] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, it should be noted that, for ease of description, only the parts relevant to this application are shown in the accompanying drawings, not the entire structure. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0048] The terms “comprising” and “having”, and any variations thereof, used in this application are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or device.

[0049] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0050] This invention discloses a method, device, computer equipment, and storage medium for quantitative measurement of fat based on multi-frequency microwave excitation. A data model is established between frequency response and tissue absorption characteristics. The absorption rate of microwaves at different frequencies by body parts is highly correlated with the degree of fat degeneration. By introducing a multi-frequency excitation mechanism, the ability to identify body parts and the accuracy of measurement are improved. It can sensitively reflect the changes in the absorption rate of microwaves by body parts. Compared with traditional single-frequency excitation methods, it has significant advantages in signal stability, noise resistance, and imaging accuracy.

[0051] Example 1:

[0052] Please see Figure 1 This embodiment provides a method for quantitative measurement of fat based on multi-frequency microwave excitation, which may include the following steps:

[0053] S100: Sequentially irradiate multiple frequency microwave pulses onto body parts to obtain thermo-ultrasound signals generated by microwave pulses of multiple frequencies corresponding to the body parts.

[0054] S200. Construct a model relating the sound pressure response of body parts to microwave pulses of multiple frequencies to fat content.

[0055] S300. Based on the generated thermo-ultrasound signals, determine the fat content of body parts by inversion from the relational model.

[0056] In one embodiment, step S100 includes:

[0057] Multiple microwave pulses of different frequencies are irradiated onto the body parts in a preset time sequence. During each irradiation of the body parts with a microwave pulse of a certain frequency, the thermo-ultrasound signal generated by the current frequency microwave pulse is simultaneously acquired by the body parts.

[0058] In practice, a frequency-tunable microwave source can be used to send microwave signals to an antenna. The frequency-tunable microwave source can send microwave signals of different frequencies to the antenna at different time intervals, allowing the antenna to irradiate microwave pulses of different frequencies. Specifically, to implement a multi-frequency microwave excitation strategy, a control circuit sends clock control signals and frequency control signals to the frequency-tunable microwave source, causing the source to send microwave signals of different frequencies to the antenna in a preset time sequence. After receiving the microwave signals from the frequency-tunable microwave source, the antenna irradiates multiple frequency microwave pulses onto body parts such as the liver or carotid artery of the target object in a preset time sequence. During each irradiation of a body part with a microwave pulse of a certain frequency, an ultrasonic transducer collects the thermo-ultrasound signal generated by the target body part after receiving the microwave pulse of the current frequency. Specifically, the microwave excitation frequency set corresponding to the frequency-tunable microwave source can be set to, but is not limited to, [specific frequencies not included in the provided text]. .

[0059] In one embodiment, step S200 includes:

[0060] S210. Construct a first relationship model between the acoustic pressure response of a body part and the electrical conductivity of the body part under microwave pulse irradiation at multiple frequencies.

[0061] S220. Construct a second relationship model between the electrical conductivity of a body part and its fat content under microwave pulse irradiation at multiple frequencies.

[0062] S230. Based on the first and second relational models, construct a relational model between the sound pressure response of body parts to microwave pulses of multiple frequencies and fat content.

[0063] In one embodiment, prior to step S210, the method further includes:

[0064] S211. Construct a first correlation model between the energy absorbed by a body part per unit volume of microwave pulses and the electrical conductivity of the body part under microwave pulse irradiation at multiple frequencies.

[0065] S212. Construct a second correlation model between the temperature rise of a body part under microwave pulse irradiation at multiple frequencies and the energy absorbed by the body part per unit volume from the microwave pulse.

[0066] S213. Construct a third correlation model between the sound pressure response of a body part and the temperature rise of the body part under microwave pulse irradiation at multiple frequencies.

[0067] Based on steps S211-S213, step S210 includes:

[0068] Based on the first correlation model, the second correlation model, and the third correlation model, a first relationship model is constructed between the sound pressure response of a body part and the electrical conductivity of the body part under microwave pulse irradiation at multiple frequencies.

[0069] For S211, the power density absorbed by biological tissues (such as body parts) under microwave pulse irradiation can be expressed as:

[0070] ;

[0071] in, Indicates the corresponding frequency The power density absorbed by the microwave pulse; Indicates the corresponding frequency The electrical conductivity of biological tissues measured by microwave pulses, in units of ; Indicates the corresponding frequency The electric field intensity of a microwave pulse within biological tissue, expressed in units of _____. .

[0072] A microwave pulse with a duration of In biology, the total energy absorbed per unit volume of biological tissue can be expressed as:

[0073] ;

[0074] in, Indicates the corresponding frequency The above formula represents the total energy absorbed per unit volume of biological tissue by a microwave pulse. It corresponds to the energy absorbed per unit volume of a body part by microwave pulses at multiple frequencies. Electrical conductivity of body parts The first correlation model between them.

[0075] According to thermodynamic principles, when biological tissue absorbs heat, it causes an instantaneous increase in temperature. It can be represented as:

[0076] ;

[0077] in, Indicates the corresponding frequency The temperature of biological tissues is increased by microwave pulses; The density of biological tissue is expressed in units of 1000 kJ / m². ; This represents the specific heat capacity at constant volume, and its unit is ______. The above formula corresponds to the temperature rise of a body part under microwave pulse irradiation at multiple frequencies. Energy absorbed by a unit volume of a body part from microwave pulses The second correlation model between them.

[0078] According to the thermoelastic effect, the volume expansion of biological tissues can be expressed as:

[0079] ;

[0080] in, Indicates the rate of change of volume expansion; This represents the initial sound pressure level (i.e., the initial thermosonic signal). Indicates the isothermal compressibility coefficient. , , Indicates specific volume at constant pressure; Indicates the speed of sound in biological tissues; The coefficient of thermal expansion of biological tissue is expressed in units of 1000 ppm. ; This represents the increase in temperature; according to the above formula, This formula corresponds to the sound pressure response of a body part under microwave pulse irradiation at multiple frequencies. With the rise in body temperature The third correlation model between them.

[0081] Will Substitute the calculation formula into In the middle, we get:

[0082] ;

[0083] in, Indicates the corresponding frequency The initial sound pressure of the microwave pulse in biological tissue.

[0084] The absorption and acoustic pressure response of biological tissues to microwave pulses of different frequencies exhibit frequency dependence; therefore, the overall thermosonic acoustic pressure of a body part can be obtained by weighted summation.

[0085] ;

[0086] in, Indicates the combined thermo-ultrasound pressure of a body part; Indicates the corresponding frequency The weighting coefficients of the microwave pulses can be set according to the signal-to-noise ratio, penetration depth, or frequency response characteristics of biological tissues, thus obtaining the sound pressure response of the body part under microwave pulse irradiation at multiple frequencies. Electrical conductivity of body parts The first relationship model between them.

[0087] In one embodiment, step 220 includes:

[0088] 221. Obtain data on the effect of fatty degeneration on the electrical conductivity of body parts under microwave pulse irradiation at multiple frequencies.

[0089] 222. Power-law distribution modeling was performed on the relevant data to obtain a second relationship model between the electrical conductivity of body parts and the fat content of body parts.

[0090] In one embodiment, considering that fatty degeneration affects the electrical conductivity of biological tissues, the following model is performed according to a power-law distribution:

[0091] ;

[0092] in, Indicates the corresponding frequency The conductivity of microwave pulses in biological tissues (i.e., body parts); Indicates the corresponding frequency The conductivity of muscle tissue under microwave pulses. Indicates the fat content of a body part; Indicates the corresponding frequency The first influence coefficient of the microwave pulse; Indicates the corresponding frequency The second influence coefficient of the microwave pulse, the above formula corresponds to the conductivity of the body part. Fat content of body parts The second relationship model between them.

[0093] In one embodiment, in step 230, a relationship model is constructed between the sound pressure response of body parts to microwave pulses of multiple frequencies and fat content, based on a first relationship model and a second relationship model, including:

[0094] Using the electrical conductivity of body parts as an intermediate parameter, and integrating the first and second relational models, a relationship model is constructed between the fused sound pressure obtained from body part detection and the sound pressure response of the body part to microwave pulses of multiple frequencies, and the fat content; the relationship model is as follows:

[0095] ;

[0096] in, This indicates the fused sound pressure obtained from detection of body parts. Indicates the first The sound pressure response of a microwave pulse at a certain frequency to a part of the body. Indicates the first The influence coefficient of microwave pulses of a certain frequency on the conductivity of body parts, where N represents the number of microwave pulse frequency types (i.e., the number of center frequencies) irradiating the body parts. This indicates the fat content of a body part.

[0097] Images were reconstructed based on thermosonometry signals, and the amplitude of the thermosonometry signals in the muscle region was standardized. Compensation was performed based on the difference between the thermosonometry signal amplitude and a fixed value, i.e., the muscle at the imaging cross-section was selected as an intrinsic parameter for analysis and comparison. Using the electrical conductivity of the body part as an intermediate parameter, the first and second relationship models were fused to obtain the following formula:

[0098] ;

[0099] in, Indicates the corresponding frequency The sound pressure of microwave pulses on body parts; This indicates the coefficient of thermal expansion of a body part.

[0100] Comprehensive coverage of all frequencies The sound pressure of the body part is measured by the microwave pulse, and the fused sound pressure obtained from the body part detection is obtained:

[0101] ;

[0102] in, This indicates the fused sound pressure level obtained from detection of body parts.

[0103] make , ,but:

[0104] ;

[0105] In one embodiment, to compute parameters in the relational model and Step 230 also includes:

[0106] A phantom with a known fat content was irradiated with microwave pulses of multiple frequencies to obtain thermosonic signals corresponding to the microwave pulses of different frequencies. The sound pressure response was obtained by least-squares fitting of the thermosonic signals. and influence coefficient .

[0107] In practice, experiments were conducted by irradiating a phantom with a known fat content with microwave pulses of multiple frequencies to obtain thermo-ultrasound signals corresponding to the microwave pulses of different frequencies. The sound pressure response was then obtained by least-squares fitting of the thermo-ultrasound signals. and influence coefficient .

[0108] In one embodiment, step S300 includes:

[0109] The generated thermo-ultrasound signals are substituted into the formula corresponding to the relational model to inversely determine the fat content of body parts.

[0110] Example 2:

[0111] Please see Figure 2 This embodiment provides a quantitative fat measurement device based on multi-frequency microwave excitation. The device may include a microwave irradiation module, a thermal ultrasound signal acquisition module, a model building module, and an inversion module. The specific descriptions of each module are as follows:

[0112] A microwave irradiation module is used to sequentially irradiate multiple frequencies of microwave pulses onto body parts.

[0113] Thermo-ultrasound signal acquisition module is used to acquire thermo-ultrasound signals generated by microwave pulses of multiple frequencies corresponding to different body parts;

[0114] The model building module is used to build models of the relationship between sound pressure response of body parts and fat content for microwave pulses of multiple frequencies.

[0115] The inversion module is used to determine the fat content of body parts by inverting from the relational model based on the generated thermo-ultrasound signals.

[0116] The fat quantitative measurement device of this embodiment operates and has the same effect as the fat quantitative measurement method of Embodiment 1 above. Therefore, the fat quantitative measurement device based on multi-frequency microwave excitation will not be described again here. It should be noted that the device provided in this embodiment is only illustrated by the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure can be divided into different functional modules to complete all or part of the functions described above.

[0117] Example 3:

[0118] Please see Figure 3 This embodiment is a specific application of a fat quantitative measurement device based on multi-frequency microwave excitation. The device includes a computer, a microwave source, an antenna, an ultrasonic transducer, an amplifier, and a digital acquisition unit.

[0119] The microwave source is preferably a frequency-tunable microwave source, controlled by a LabVIEW program on a computer, and employs opto-isolation to enhance electrical safety and anti-interference performance. To implement a multi-frequency microwave excitation strategy, a control circuit sends clock and frequency control signals to the frequency-tunable microwave source, causing the tunable pulse microwave source to send microwave signals of different frequencies to the antenna in a preset time sequence. Upon receiving the microwave signals from the frequency-tunable microwave source, the antenna irradiates multiple frequency microwave pulses onto the target body part in a preset time sequence. Typical parameters of the frequency-tunable microwave source include a pulse width of 140ns, a peak power of 100kW, and operating frequencies including but not limited to 2.0GHz, 3.0GHz, 4.0GHz, 5.0GHz, and 6.0GHz, with an adjustable repetition frequency ranging from 10Hz to 100Hz.

[0120] A microwave source and antenna (preferably a linearly polarized dipole antenna) are used to radiate microwave pulses onto the abdominal region of the human body. The microwave signals penetrate the skin and are absorbed by the body parts. Different frequencies of microwave pulses induce varying degrees of thermo-ultrasound effects in the body parts, thereby generating broadband ultrasound signals. The intensity of the thermo-ultrasound signal is affected by the dielectric properties and fat content of the body parts; therefore, the composition of the body parts can be inferred from their amplitude and frequency responses.

[0121] Thermo-ultrasound signals generated by body parts can be received by an ultrasonic transducer (preferably a 128-element semi-circular ultrasonic transducer). The ultrasonic transducer can operate at a frequency of 3.5MHz, with a bandwidth greater than 86% and a focal length of 60mm, enabling high-sensitivity and wide-angle reception of thermo-ultrasound signals. After amplification by an amplifier (preferably a pre-amplifier with low noise), the thermo-ultrasound signal is input to a digital acquisition unit with a sampling accuracy of 14 bits, a sampling frequency of 40 MHz, and support for 128-channel parallel acquisition.

[0122] The multi-frequency thermosonic signals acquired by the digital acquisition unit are transmitted to a computer via a data bus for real-time processing. The computer's LabVIEW software interface, developed using the QT platform, enables unified control over the acquisition process, microwave frequency switching, data storage, and image display. Image reconstruction, developed using MATLAB, employs a GPU-accelerated filtered back-projection algorithm for two-dimensional image reconstruction, achieving spatial localization and intensity visualization of the thermosonic source.

[0123] Please see Figure 4 (a)-(e) are comparative images from multi-frequency thermosonography imaging experiments using liver or carotid artery phantoms with fat contents of 5%, 10%, 20%, 40%, and 80% and those with 0% fat contents, respectively. Images acquired during microwave pulse irradiation at each frequency band were processed using a filtered back-projection algorithm to extract the thermosonography signal. The results show that the fat content in the thermosonography signal intensity domain exhibits a consistent nonlinear relationship, and the inversion accuracy can be controlled within ±3%, demonstrating excellent robustness and repeatability.

[0124] The process of the above-mentioned multi-frequency thermosonography imaging experiment mainly includes:

[0125] (1) A frequency-tunable microwave source is used to generate multiple sets of microwave pulses with center frequencies of 2.0 GHz, 3.0 GHz, 4.0 GHz, 5.0 GHz, and 6.0 GHz, respectively. Each set of microwave pulses has the following parameters: pulse width of 140 ns, peak power of 100 kW, and repetition frequency of 10 Hz to 100 Hz. The microwave pulses are transmitted via coaxial cable to a linearly polarized dipole sub-antenna with dimensions of 60 mm × 60 mm × 45 mm for transmission, irradiating the target area (e.g., the abdominal region of the human body). Each set of frequency microwave pulses independently irradiates the target area and simultaneously acquires thermo-ultrasonic signals, completing multi-band microwave excitation.

[0126] (2) The position and angle between the antenna and the ultrasonic transducer are adjusted by the mechanical adjustment system to ensure that an effective coupling channel is formed between the antenna and the ultrasonic transducer, to obtain the best acoustic window for cross-sectional images of body parts, to ensure that the target area is consistent when irradiated by microwave pulses of different frequencies, and to reduce the impact of positioning error on quantitative analysis.

[0127] (3) Apply an ultrasonic coupler to the surface of the antenna and ultrasonic transducer to reduce interface reflection. Then, use the ultrasonic transducer to detect the thermo-ultrasonic signal generated after the body part absorbs microwaves. The thermo-ultrasonic signals under microwave excitation in each frequency band are collected and stored in the computer. The collection parameters are: 128 channels, 40MHz sampling frequency, and 14bit sampling accuracy.

[0128] (4) The collected thermo-ultrasound signals were processed by computer using the MATLAB+QT GUI system: The GPU-accelerated filtering back projection algorithm was used to reconstruct the images of each frequency. The target region (body parts) and reference region (muscles) were extracted from the reconstructed images. The amplitude of the muscle region was normalized for the images at different frequencies, thereby eliminating individual differences and the influence of system noise.

[0129] from Figure 4 It is evident that as the fat content increases, the amplitude of the thermo-ultrasound signal of the phantom gradually weakens, demonstrating a good response to changes in fat content.

[0130] Example 4:

[0131] Please see Figure 5 This embodiment provides a computer device including a processor, a memory, an input device, a display device, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. When the processor executes the computer programs stored in the memory, it implements the fat quantification measurement method of Embodiment 1 described above.

[0132] Example 5:

[0133] This invention discloses a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the fat quantitative measurement method of Embodiment 1 described above.

[0134] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, including read-only memory (ROM), random access memory (RAM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), one-time programmable read-only memory (OTPROM), electrically-Erasable Programmable Read-Only Memory (EEPROM), compactdisc read-only memory (CD-ROM) or other optical disc storage, disk storage, magnetic tape storage, or any other computer-readable medium capable of carrying or storing data.

[0135] In summary, this invention establishes a data model between frequency response and tissue absorption characteristics. The absorption rate of microwaves at different frequencies by body parts is highly correlated with the degree of fat degeneration. By introducing a multi-frequency excitation mechanism, the ability to identify body parts and the accuracy of measurement are improved, thereby enabling the quantitative detection of fat content in body parts.

[0136] The foregoing has provided a detailed description of a method, apparatus, computer device, and storage medium for quantitative measurement of fat based on multi-frequency microwave excitation, as disclosed in the embodiments of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for quantitative measurement of fat based on multi-frequency microwave excitation, characterized in that, The method includes: Multiple microwave pulses of different frequencies are sequentially irradiated onto body parts to obtain thermo-ultrasound signals generated by microwave pulses of different frequencies corresponding to different body parts. Construct a model relating the acoustic pressure response of body parts to microwave pulses of multiple frequencies to fat content; The fat content of body parts is determined by inversion from the relational model based on the generated thermo-ultrasound signals.

2. The method for quantitative measurement of fat according to claim 1, characterized in that, The step of sequentially irradiating multiple frequencies of microwave pulses onto a body part and acquiring thermo-ultrasound signals generated by microwave pulses of multiple frequencies corresponding to the body part includes: Multiple microwave pulses of different frequencies are irradiated onto the body parts in a preset time sequence. During each irradiation of the body parts with a microwave pulse of a certain frequency, the thermo-ultrasound signal generated by the microwave pulse of the current frequency is simultaneously collected from the body parts.

3. The method for quantitative measurement of fat according to claim 1, characterized in that, The model constructing the relationship between the sound pressure response of body parts and fat content for microwave pulses of multiple frequencies includes: A first-order relationship model was constructed between the acoustic pressure response of a body part and its electrical conductivity under microwave pulse irradiation at multiple frequencies. A second relationship model was constructed between the electrical conductivity of body parts and the fat content of body parts under microwave pulse irradiation at multiple frequencies. Based on the first and second relational models, a model is constructed to represent the relationship between the sound pressure response of body parts to microwave pulses of multiple frequencies and fat content.

4. The method for quantitative measurement of fat according to claim 3, characterized in that, Before constructing the first relationship model between the acoustic pressure response of a body part and its electrical conductivity under microwave pulse irradiation at multiple frequencies, the method further includes: A first correlation model was constructed between the energy absorbed by a body part per unit volume under microwave pulse irradiation at multiple frequencies and the electrical conductivity of the body part. A second correlation model was constructed between the temperature rise of body parts under microwave pulse irradiation at multiple frequencies and the energy absorbed by the body parts per unit volume of microwave pulses. A third correlation model was constructed between the sound pressure response of body parts and the temperature rise of body parts under microwave pulse irradiation at multiple frequencies. The first relationship model between the acoustic pressure response and electrical conductivity of a body part under microwave pulse irradiation at multiple frequencies includes: Based on the first correlation model, the second correlation model, and the third correlation model, a first relationship model is constructed between the sound pressure response of a body part and the electrical conductivity of the body part under microwave pulse irradiation at multiple frequencies.

5. The method for quantitative measurement of fat according to claim 3, characterized in that, The second relationship model between the electrical conductivity of a body part and its fat content under microwave pulse irradiation at multiple frequencies includes: To obtain data on the effect of fatty degeneration on the electrical conductivity of body parts under microwave pulse irradiation at multiple frequencies; A power-law distribution model was used to model the influence data, resulting in a second relationship model between the electrical conductivity of body parts and the fat content of body parts.

6. The method for quantitative measurement of fat according to claim 3, characterized in that, The process of constructing a model relating the sound pressure response of body parts to microwave pulses of multiple frequencies to fat content, based on the first and second relational models, includes: Using the electrical conductivity of body parts as an intermediate parameter, and integrating the first and second relationship models, a relationship model is constructed between the fused sound pressure obtained from body part detection and the sound pressure response of the body part to microwave pulses of multiple frequencies, and the fat content; the relationship model is as follows: ； in, This indicates the fused sound pressure obtained from detection of body parts. Indicates the first The sound pressure response of a microwave pulse at a certain frequency to a part of the body. Indicates the first The influence coefficient of microwave pulses of a certain frequency on the conductivity of a body part, where N represents the number of different frequencies of microwave pulses irradiating the body part. This indicates the fat content of a body part.

7. The method for quantitative measurement of fat according to claim 6, characterized in that, The step of constructing a model relating the sound pressure response of body parts to microwave pulses of multiple frequencies to fat content, based on the first and second relational models, further includes: By irradiating a phantom with a known fat content with microwave pulses of multiple frequencies, thermosonic signals of the phantom corresponding to the microwave pulses of multiple frequencies were obtained. The acoustic pressure response was obtained by least-squares fitting of the thermosonic signal. and influence coefficient .

8. A quantitative measurement of fat based on multi-frequency microwave excitation, characterized in that, The device includes: A microwave irradiation module is used to sequentially irradiate multiple frequencies of microwave pulses onto body parts. Thermo-ultrasound signal acquisition module is used to acquire thermo-ultrasound signals generated by microwave pulses of multiple frequencies corresponding to different body parts; The model building module is used to build models of the relationship between sound pressure response of body parts and fat content for microwave pulses of multiple frequencies. The inversion module is used to determine the fat content of body parts by inverting from the relational model based on the generated thermo-ultrasound signals.

9. A computer device comprising a processor and a memory for storing a processor-executable program, characterized in that, When the processor executes the program stored in the memory, it implements the fat quantitative measurement method according to any one of claims 1-7.

10. A computer-readable storage medium storing a program, characterized in that, When the program is executed by the processor, it implements the fat quantitative measurement method according to any one of claims 1-7.

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