An acoustic field adjustable planar ultrasound transducer and an ultrasound treatment system

Abstract

The application discloses a plane ultrasonic transducer with adjustable sound field and an ultrasonic treatment system. The plane ultrasonic transducer comprises a transducer body and a sound field adjusting device fixedly arranged on a radiation surface of the transducer body, wherein the sound field adjusting device comprises an impedance matching layer, an acoustic diffusion layer and a coupling pad. The impedance matching layer is used for realizing sound impedance transition, the acoustic diffusion layer is provided with randomly distributed holes to improve sound field uniformity, and the coupling pad is used for adjusting impedance matching and adjusting an axial distance between the transducer and a target area. The ultrasonic treatment system comprises the above transducer and a control module. The control module receives a sound field mode selection instruction, adjusts the axial distance to a preset range corresponding to a near field mode or a far field mode by adjusting a thickness of the coupling pad or driving the transducer to move, and controls the transducer to work according to preset parameters. Through sound field adjustment and axial distance differential adjustment, the application realizes active switching of two working modes of the near field high sound intensity and the far field uniform irradiation, and improves energy utilization rate and treatment consistency.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic control technology, specifically to a planar ultrasonic transducer with adjustable sound field and an ultrasonic therapy system. Background Technology

[0002] Ultrasound is widely used in neuromodulation and tissue stimulation due to its non-invasive nature. Low-intensity pulsed ultrasound (LIPUS), characterized by low-intensity, pulsed output, can achieve targeted acoustic energy delivery while minimizing thermal effects and has been explored for improving metabolic diseases. In existing technologies, LIPUS treatment devices typically operate with fixed-parameter planar ultrasound transducers (such as planar transducers) and fixed irradiation distances or a single coupling method. This setup essentially fixes the system in a single acoustic field mode (usually operating in the near-field region or at a fixed distance by default). This static and singular mode setting not only ignores the significant differences in sound pressure distribution, uniformity, and attenuation patterns between the near and far-field regions of the ultrasound field, but more importantly, it lacks a control logic that can actively select and switch to different acoustic field modes (such as near-field or far-field modes) based on the treatment target. Therefore, existing treatment systems cannot respond to different clinical instructions or treatment scenario requirements by dynamically adjusting the axial distance between the transducer and the target area, thus failing to operate the system in the most suitable acoustic field mode. This can lead to a mismatch between the sound field characteristics during treatment and clinical needs, resulting in insufficient sound energy utilization and a need to improve the consistency of treatment coverage. Therefore, a solution is needed that allows for selectable sound field modes and intelligent distance adjustment.

[0003] Furthermore, as a core component of ultrasound therapy, planar ultrasound transducers, due to their flat ultrasonic emitting end face, are prone to forming high sidelobe sound fields and uneven energy distribution in the irradiated target area, resulting in poor sound field uniformity. Traditional solutions, such as using lenses and transducer arrays, suffer from problems such as complex structures and high costs. Although there have been attempts to use porous materials for acoustic diffusion, these have drawbacks such as limited scattering effects due to the regular distribution of pores, a lack of clear relationship between pore size parameters and operating wavelength, and a lack of system integration design with impedance matching layers.

[0004] However, existing technologies not only lack research on the acoustic characteristics of LIPUS, making it impossible to utilize acoustic characteristics for precise treatment, but also lack technical solutions for constructing selectable, multi-mode sound field control systems based on differences in acoustic characteristics.

[0005] Therefore, there is an urgent need for a comprehensive technical solution that is based on the differences in ultrasonic acoustic characteristics and enables selectable sound field modes and adjustable distances, in order to improve the treatment efficiency, consistency and safety of LIPUS. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a planar ultrasound transducer with adjustable sound field and an ultrasound therapy system. By integrating an impedance matching layer, an acoustic diffusion layer with random holes, and an adjustable coupling pad onto the planar ultrasound transducer, and controlling the axial distance to switch between near-field and far-field modes, the problems of single sound field mode, low energy utilization, and poor sound field uniformity in existing ultrasound therapy are solved.

[0007] To achieve the above objectives, the present invention provides the following technical solution: The present invention provides a planar ultrasonic transducer with adjustable sound field and an ultrasonic therapy system. The beneficial effects of this invention are as follows: This invention provides a planar ultrasonic transducer with adjustable sound field and an ultrasonic therapy system. The planar ultrasonic transducer includes a transducer body and a sound field adjustment device fixedly disposed on its radiating surface. The sound field adjustment device includes an impedance matching layer, an acoustic diffusion layer, and a coupling pad. The impedance matching layer is used to achieve acoustic impedance transition; the acoustic diffusion layer has randomly distributed holes to improve sound field uniformity; and the coupling pad is used to adjust impedance matching and the axial distance between the transducer and the target area. The ultrasonic therapy system includes the above-mentioned transducer and a control module. The control module receives a sound field mode selection command and adjusts the axial distance to a preset range corresponding to the near-field or far-field mode by adjusting the thickness of the coupling pad or driving the transducer to move, and controls the transducer to operate according to preset parameters. This invention, through sound field adjustment and differential adjustment of axial distance, achieves active switching between two working modes: high near-field acoustic intensity and uniform far-field irradiation, improving energy utilization and treatment consistency. Compared with the prior art, it has the following advantages: 1. Active selection and switching of sound field mode: Through differential adjustment of axial distance, the system can work in near field (high sound intensity, concentrated energy) or far field (uniform sound field, wide coverage) mode to match different depths and types of treatment targets, thus solving the problem of single sound field mode in existing ultrasound treatment.

[0008] 2. Dual regulation of sound field uniformity and energy transmission efficiency: By integrating an acoustic diffusion layer and an impedance matching layer, the sound field emitted by the transducer is shaped at the source. Randomly distributed holes effectively scatter ultrasonic waves, break up side lobes, and significantly improve sound field uniformity; the impedance matching layer can minimize the reflection loss of acoustic energy at the interface between the transducer and the target tissue, thereby improving energy utilization.

[0009] 3. Synergistic Effect: Macroscopic "distance adjustment" and microscopic "sound field shaping" can work together. For example, in far-field mode, a more uniform basic sound field, after being adjusted by the diffusion layer, can achieve a wider range and higher consistency of deep tissue irradiation; in near-field mode, the adjusted high-intensity sound field can act more accurately and efficiently on shallow target points.

[0010] 4. Simple structure and controllable cost: The sound field adjustment device has a compact structure and can be easily integrated into existing planar transducers using processes such as 3D printing. It does not require large-scale modification of the host and control logic of the treatment system and has good prospects for industrial application.

[0011] 5. Sufficient application validation: Animal experiments on a type 2 diabetic mouse model have demonstrated that the system of this invention (especially the far-field mode combined with the modulated sound field) can significantly improve blood glucose homeostasis and insulin sensitivity, with good safety, showing its great potential for clinical translation.

[0012] The above and other objects, advantages, and features of the present invention will be more fully set forth and demonstrated through the following detailed description of specific embodiments in conjunction with the accompanying drawings. Those skilled in the art, upon referring to the following detailed description and the accompanying drawings, will be able to better understand and realize the above advantages of the present invention. Other objects, features, and advantages of the present invention will become clearer after being described in detail in the detailed description section in conjunction with the accompanying drawings. Attached Figure Description

[0013] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the following drawings are provided for illustration.

[0014] Figure 1 This is a schematic diagram of the sound field adjustment device of the present invention; Figure 2 A side view of a multi-layer stepped impedance matching layer; Figure 3 A partial top view of the randomly porous diffusion layer; Figure 4 A schematic diagram of a diabetes treatment efficacy evaluation system based on sound field distance differences; Figure 5 A schematic diagram of the acoustic characteristics of an ultrasonic field using a LIPUS beammap. Figure 6 A schematic diagram of the acoustic characteristics of a diabetes treatment system based on sound field distance differences; Figure 7 This is a schematic diagram illustrating the evaluation process of the effect of regulating high blood sugar. Figure 8 This is a schematic diagram illustrating the changes in fasting blood glucose levels during a multi-group controlled experiment. Figure 9 This is a schematic diagram of random blood glucose changes during a multi-group control experiment; Figure 10 This is a schematic diagram illustrating blood glucose changes during an insulin test in a multi-group controlled experiment. Figure 11 This is a schematic diagram illustrating blood glucose changes during a glucose tolerance test in a multi-group controlled experiment. In the diagram, 1 represents the signal generator, 2 represents the power amplifier, 3 represents the planar ultrasound transducer, 4 represents the sound field adjustment device, 5 represents the liver, 6 represents the pancreas, and 7 represents LIPUS stimulation. Detailed Implementation

[0015] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention. Example 1

[0016] like Figure 1 As shown, Figure 1 This is a schematic diagram of the sound field adjustment device of the present invention; The planar ultrasonic transducer with adjustable sound field provided in this embodiment includes a planar ultrasonic transducer body and a sound field adjustment device fixedly disposed on the radiation surface of the planar ultrasonic transducer body. The sound field adjustment device includes an impedance matching layer, an acoustic diffusion layer, and a coupling pad. The impedance matching layer is disposed between the acoustic diffusion layer and the planar ultrasonic transducer to realize the acoustic impedance transition between the transducer and the target medium. The acoustic diffusion layer is disposed on the impedance matching layer and has multiple randomly distributed holes for scattering ultrasonic waves to improve the uniformity of the sound field. The coupling pad is disposed between the acoustic diffusion layer and the skin to adjust the impedance matching between the acoustic diffusion layer and the skin, and to adjust the axial distance between the planar ultrasonic transducer in the ultrasonic generator and the irradiation target area.

[0017] In this embodiment, the thickness of the coupling pad is configured such that: when a coupling pad of a first thickness is used, the planar ultrasonic transducer operates in near-field mode; when a coupling pad of a second thickness is used, the planar ultrasonic transducer operates in far-field mode, and the second thickness is greater than the first thickness.

[0018] In this embodiment, the impedance matching layer adopts a multi-layer stepped gradient structure, including multiple impedance gradient layers, and the acoustic impedance of each layer increases linearly or exponentially along the direction of ultrasonic wave propagation.

[0019] In this embodiment, the impedance matching layer is an air cavity metamaterial matching layer, which includes a regularly arranged array of air cavities. The diameter of the air cavities is 1 / 10 to 1 / 5 of the working wavelength, and the depth is 1 / 4 of the working wavelength.

[0020] In this embodiment, the aperture of the holes in the acoustic diffusion layer is between 1 / 8 and 1 / 5 of the working wavelength; the hole depth is between 1 / 2 and 2 of the working wavelength; and the fill rate is between 30% and 50%.

[0021] This embodiment provides an ultrasound therapy system, comprising: The aforementioned planar ultrasonic transducer with adjustable sound field; The control module, which is communicatively connected to the planar ultrasonic transducer, is used for: Receive or generate a sound field mode selection command, wherein the sound field mode includes at least a near-field mode and a far-field mode; The coupling pad is controlled to adjust the axial distance to a preset axial distance range corresponding to the selected sound field mode; The planar ultrasound transducer is controlled to operate according to preset treatment parameters at the preset axial distance.

[0022] In this embodiment, the control module includes an axial distance control unit, which drives the planar ultrasonic transducer or the coupling pad to move to change the axial distance; the thickness of the coupling pad is replaceable or adjustable.

[0023] The coupling pad described in this embodiment includes a thin coupling pad for near-field mode, a thick coupling pad for far-field mode, or a liquid-fillable coupling cavity.

[0024] The control module described in this embodiment also includes: A parameter preset unit is used to set and store the treatment parameters, which include acoustic power, pulse repetition frequency, duty cycle and single treatment time. The real-time feedback unit is used to monitor the acoustic power output by the planar ultrasonic transducer through an impedance matching circuit and provide feedback signals to the control module for dynamic adjustment.

[0025] In this embodiment, the control module is further configured to automatically adjust the thickness of the coupling pad or the emission parameters of the planar ultrasonic transducer based on the acoustic power changes monitored by the real-time feedback unit, so as to maintain the axial distance within the preset axial distance range.

[0026] The control module in this embodiment also includes: At least one sensor is used to monitor the status parameters of the treatment target area and / or the operating status parameters of the transducer in real time; The control module is connected to the sensor, the sound field adjustment device, and the coupling pad respectively. The control module is configured to: calculate a first control signal in real time using a closed-loop feedback control algorithm based on the state parameters monitored by the sensor, and dynamically adjust the thickness of the coupling pad according to the first control signal so that the planar ultrasonic transducer operates in a preset optimal near-field mode or far-field mode; simultaneously, calculate a second control signal in real time using the closed-loop feedback control algorithm based on the state parameters monitored by the sensor, and dynamically adjust the acoustic characteristics of the acoustic diffusion layer and / or the impedance matching layer according to the second control signal to synergistically adjust the sound field uniformity and transmission efficiency of the ultrasonic wave in the optimal operating mode. Example 2: Ultrasonic Therapy System with Integrated Sound Field Adjustment Device Based on Example 1, this embodiment further integrates a sound field adjustment device on the radiating surface of the planar ultrasonic transducer to achieve more precise sound field control.

[0027] 1. Structure and Principle of Sound Field Adjustment Device like Figure 1 As shown, the device includes an impedance matching layer and an acoustic diffusion layer stacked sequentially on the radiating surface of a planar transducer, as well as an ultrasound coupling pad that contacts the skin.

[0028] The function of the impedance matching layer is to achieve a smooth transition of acoustic impedance between the transducer and the tissue, minimizing sound wave reflection and maximizing energy transmittance. This invention employs a multi-layered, stepped-gradient impedance matching layer design. For example... Figure 2 As shown, a four-layer impedance gradient layer is used, with the acoustic impedance of each layer increasing in a gradient along the direction of ultrasonic wave propagation. For a planar transducer operating at a frequency of 1 MHz in a water medium (acoustic impedance 1.5 MRayl), the calculated wavelength λ = 1.5 mm. To achieve maximum transmission, the thickness of each layer can be designed to be 1 / 4 of the operating wavelength, approximately 0.38 mm. The parameters of the four impedance gradient layers in this invention are as follows: Figure 3As shown, the acoustic diffusion layer has multiple randomly distributed pores, which scatter ultrasonic waves, disrupting the regular wavefront and thus suppressing sidelobes, resulting in a more uniform sound field energy distribution. For a planar transducer operating at 1MHz in an aqueous medium (acoustic impedance 1.5 MRayl), the calculated wavelength λ = 1.5mm. The acoustic diffusion layer uses a photocurable resin material (acoustic impedance 2.0-2.5 MRayl), with the following parameters: pore diameter d = λ / 8 - λ / 5 = 0.19mm - 0.30mm, taking the midpoint 0.25mm; pore depth h = 0.75mm - 3mm, taking the midpoint 1.1mm; fill rate = 40%; the pores are randomly distributed, and a random coordinate point array is generated using a Python script to ensure that the spacing between adjacent pores is not less than 0.3mm. The overall thickness of the diffusion layer is designed to be 1.1mm, and it is formed using SLA photocurable 3D printing with a printing resolution of 50μm.

[0029] 2. Collaborative work mode In the system of this embodiment, the control module can utilize distance adjustment and sound field adjustment simultaneously or selectively. For example: Far-field + Adjustment Mode: The sound field adjustment module adjusts the axial distance to the far-field range (e.g., 30mm), while the transducer integrates a sound field adjustment device. In this mode, the transducer first emits a uniform sound field that has undergone diffusion and matching adjustment. This sound field then propagates over the far-field distance, ultimately forming a large-area, highly uniform, and low-attenuation energy deposition in deep target areas (e.g., liver, pancreas). The LIPUS-30mm group in T2DM mouse experiments can be considered a prototype of this mode, achieving the best therapeutic effect.

[0030] Near-field + Adjustment Mode: Control the axial distance to the near-field range (e.g., 5mm). In this mode, the adjusted transducer can output a near-field sound beam with lower side lobes and more concentrated main lobe energy, which is very suitable for shallow targets that require precise, high-intensity stimulation.

[0031] In summary, the sound field control system and its sound field adjustment device of the ultrasound therapy system provided in this embodiment achieve precise, flexible, and efficient control of therapeutic ultrasound through a dual mechanism of macroscopic distance adjustment and microscopic sound field shaping. Animal experiments and physical tests have verified its significant beneficial effects, providing a novel and high-performance technical solution for ultrasound therapy, especially for non-invasive treatment of metabolic diseases.

[0032] like Figures 4-7 The diagram illustrates the components (including a signal generator, power amplifier, and planar ultrasonic transducer) and acoustic characteristics of a low-intensity pulsed ultrasound (LIPUS) generator. Specifically: Figure 4This is a schematic diagram of a LIPUS generator for a diabetes treatment system based on acoustic field distance differentiation; it illustrates the components of the low-intensity pulsed ultrasound (LIPUS) generator (including a signal generator, power amplifier, and planar ultrasound transducer) and its acoustic characteristics. The hardware connections and layout of the LIPUS generator are shown. In the figure, 1 represents the signal generator; 2 represents the power amplifier; 3 represents the planar ultrasound transducer; 4 represents the acoustic field modulation device; 5 represents the liver; 6 represents the pancreas; and 7 represents LIPUS stimulation. In this embodiment, the control module controls the signal generator and acoustic field modulation module (e.g., control lines); the signal generator is connected to the power amplifier, and the power amplifier is connected to the planar ultrasound transducer, forming an electrical signal transmission path. The planar ultrasound transducer sends ultrasound waves to the patient's body (or target organ) through a coupling pad, forming an energy transfer path.

[0033] Figure 5 This is a schematic diagram of the acoustic characteristics of an ultrasonic field using a LIPUS beammap. The transducer output surface is located in the XOZ plane, with an initial distance of 0 mm. The center point of the longest diameter of the transducer output surface is at 0 mm on the horizontal axis. The vertical axis represents the distance from the transducer surface, and the horizontal axis represents the distance from each point on the transducer output surface to the center point. Figure 5 This diagram illustrates the sound field distribution along the transducer's Y-axis from 0 to 45 mm, and provides schematic XOZ plane images of the sound axis cross-sections at 5 mm, 10 mm, 20 mm, and 30 mm. It demonstrates that the ultrasonic sound field distribution varies with different sound field distances.

[0034] Figure 6 This is a schematic diagram of the acoustic characteristics of the LIPUS generator in a diabetes treatment system based on acoustic field distance differentiation. The diagram shows the acoustic field intensity along the two mutually perpendicular maximum diameters (X-axis and Z-axis) on the transducer output surface when the acoustic axis distance (Y-axis) is fixed. At 5 mm, the acoustic intensity along the X and Z axes is high but unevenly distributed; at 30 mm, the acoustic intensity along the X and Z axes is low but uniformly distributed. This indicates that as the distance Y increases, the ultrasonic acoustic field intensity decreases and the uniformity increases.

[0035] The LIPUS generator in the ultrasound therapy system based on acoustic field distance difference described in this embodiment consists of a 33510B signal generator (Keysight Technologies Inc., USA), a 2200L power amplifier (Electronics & Innovation LTD., USA), and a planar ultrasound transducer (Chongqing Ronghai Ultrasonic Medical Engineering Research Center Co., Ltd.). The planar ultrasound transducer has a center frequency of 1MHz and a maximum diameter of 25mm.

[0036] LIPUS Acoustic Characteristics: The acoustic characteristics of the ultrasonic field are reflected by the LIPUS beammap. A hydrophone was placed in degassed water under the transducer and scanned along the acoustic axis to obtain the axial sound pressure distribution at 0-45 mm in the XZ plane. Cross-sectional sound fields were obtained by scanning at distances of 5, 10, 20, and 30 mm from the transducer, with measured sound pressures of 5.97, 5.52, 6.55, and 5.96 Pa, respectively. The results of ultrasonic power attenuation variation show that as the axial distance from the planar transducer increases, the uniformity of the sound field increases, and the sound attenuation increases.

[0037] The planar ultrasound output from the transducer has two characteristic regions: the near field (close to the transducer end) and the far field (far from the transducer end). The farther away from the transducer, the lower the complexity of the sound field and the higher the sound attenuation. Within 0-30mm of the acoustic axis, the ultrasound intensity is high and the uniformity is low. After 30mm, the uniformity of the ultrasound improves, but the energy continuously attenuates. Considering the influence of axial distance on the uniformity of the ultrasound field and the sound pressure distribution, as well as the LIPUS irradiation effect, the Near Field (NF) is selected at 5mm from the transducer surface, and the Far Field (FF) is selected at 30mm. The near-field and far-field irradiation modes are adjusted by changing the thickness of the coupling pad. Considering the ultrasound itself and its attenuation in the coupling pad, each group of LIPUS devices is calibrated to provide an average power of 0.2W on the skin surface.

[0038] LIPUS Treatment Protocol: Based on the above results, the liver and pancreas regions of T2DM mice were irradiated with LIPUS. A stimulation point was set 15 mm from the xiphoid process, and the transducer center point was placed perpendicularly at the stimulation point. A solid coupling pad was placed on the shaved abdomen of the mouse as the acoustic medium. The axial distance was adjusted by changing the thickness of the coupling pad. The treatment parameters were as follows: duty cycle = 20%, pulse repetition frequency = 1 kHz, sound intensity = 200 mW / cm². 2 Single irradiation time = 10 min, total treatment time = 35 days.

[0039] The experimental design of this embodiment is based on the following: 5mm was chosen as the representative point for the near field (NF) because this distance is much smaller than the near field length of the transducer, ensuring that it is within the typical near-field high-intensity oscillation region. 30mm was chosen as the representative point for the far field (FF) because this distance exceeds the near field length, entering the relatively uniform far field region. At the same time, after considering tissue attenuation, this distance still allows sufficient acoustic energy to act on the deep target area of ​​the mouse liver and pancreas (approximately 5-8mm deep).

[0040] Mechanism analysis of the difference in therapeutic efficacy: Experimental results showed that the FF group (30mm) was significantly superior to the NF group (5mm) in improving glycemic homeostasis and insulin sensitivity in T2DM mice. This unexpected technical effect may stem from: 1. Advantage of sound field uniformity: The more uniform sound field distribution in far-field mode may achieve more consistent and comprehensive stimulation of large liver tissues, thereby more effectively regulating the systemic glucose metabolism network.

[0041] 2. Differences in energy deposition characteristics: The high intensity and non-uniform sound field in the near field may cause energy to be too concentrated locally, while the relatively uniform and moderate energy deposition in the far field may be more conducive to triggering ideal biological regulatory mechanisms (such as activation of anti-inflammatory pathways) rather than simple thermal effects.

[0042] 3. Matching with biological targets: Treatment of metabolic diseases may require action on a relatively broad neuroendocrine network, and the pattern of far-field uniform irradiation may be a better match for such planar targets.

[0043] Example 3: The sound field control system of an ultrasound therapy system and its usage steps The core of this embodiment lies in actively and controllably adjusting the axial distance to precisely set the system to operate in a preset near-field or far-field mode, thereby maximizing the treatment efficiency and safety in each mode. Detailed T2DM mouse treatment validation data ( Figures 7-11 This fully demonstrates the effectiveness of the method and system.

[0044] This embodiment provides an ultrasound therapy system, including the aforementioned planar ultrasound transducer with adjustable sound field and a control module communicatively connected to the planar ultrasound transducer. The control module is used to receive or generate a sound field mode selection command that includes at least a near-field mode and a far-field mode, control the coupling pad to adjust the axial distance to a preset axial distance range corresponding to the selected sound field mode, and control the planar ultrasound transducer to operate according to preset treatment parameters at the preset axial distance.

[0045] The control module includes an axial distance control unit for driving the planar ultrasonic transducer or coupling pad to move and change the axial distance. The thickness of the coupling pad is replaceable or adjustable, specifically including a thin coupling pad for near-field mode, a thick coupling pad for far-field mode, or a fluid-fillable coupling cavity.

[0046] The control module also includes a parameter preset unit and a real-time feedback unit. The parameter preset unit is used to set and store treatment parameters, including acoustic power, pulse repetition frequency, duty cycle, and single treatment time. The real-time feedback unit monitors the acoustic power output of the planar ultrasound transducer through an impedance matching circuit and provides feedback signals to the control module for dynamic adjustment. The control module is also configured to automatically adjust the thickness of the coupling pad or the emission parameters of the planar ultrasound transducer based on changes in acoustic power monitored by the real-time feedback unit to maintain the axial distance within a preset axial distance range.

[0047] The control module also includes at least one sensor for real-time monitoring of the state parameters of the treatment target area and / or the operating state parameters of the transducer. The control module is connected to the sensor, the sound field adjustment device, and the coupling pad, respectively. The control module is configured to: calculate a first control signal in real-time using a closed-loop feedback control algorithm based on the state parameters monitored by the sensor; and dynamically adjust the thickness of the coupling pad according to the first control signal to ensure the planar ultrasonic transducer operates in a preset optimal near-field or far-field mode; simultaneously, calculate a second control signal in real-time using a closed-loop feedback control algorithm based on the state parameters monitored by the sensor; and dynamically adjust the acoustic characteristics of the acoustic diffusion layer and / or impedance matching layer according to the second control signal to synergistically adjust the sound field uniformity and transmission efficiency of the ultrasound waves in the optimal operating mode. The first and second control signals are jointly determined by the control module based on the same adjustment objective function.

[0048] The ultrasound therapy system in this embodiment comprises an ultrasound generating device built from a planar ultrasound transducer. This device consists of a signal generator, a power amplifier, and a planar transducer connected in sequence, used to generate and emit ultrasound energy. The axial distance control unit in the sound field adjustment module uses a precision mechanical drive to achieve axial movement of the transducer or coupling pad. The system also includes a mode selection interface as a user interaction layer, allowing the operator to input sound field mode selection commands and set treatment parameters. The control module coordinates the ultrasound generating device and the sound field adjustment module to work together according to the received commands, including calculating the target axial distance based on the selected sound field mode and driving adjustment, and converting treatment parameters into electrical signal control commands and sending them to the ultrasound generating device.

[0049] The usage process of the ultrasound therapy system provided in this embodiment is specifically carried out according to the following steps: 1. Obtain a sound field mode selection command, wherein the sound field mode includes at least a near-field mode and a far-field mode; 2. In response to the sound field mode selection command, the control-sound field adjustment module adjusts the axial distance between the planar ultrasonic transducer and the irradiation target area so that the planar ultrasonic transducer operates within the preset axial distance range corresponding to the selected sound field mode. In this embodiment, the irradiation target area is the liver and pancreas irradiation target area; the planar ultrasound transducer is a planar ultrasound transducer; wherein, the preset axial distance corresponding to the far-field mode is 25-35mm; At the preset axial distance, the control-ultrasound generator outputs ultrasound energy according to preset treatment parameters; the treatment parameters include: sound power of 2W, pulse repetition frequency of 1kHz, and duty cycle of 20%.

[0050] The control method provided in this embodiment can be used in an ultrasound therapy system for treating type 2 diabetes. It employs a planar ultrasound transducer with a diameter of 25 mm and a center frequency of 1 MHz.

[0051] In this embodiment, the steps for controlling the sound field adjustment module to adjust the axial distance include: An axial distance control unit moves the planar ultrasonic transducer or coupling pad assembly to change the distance from the radiation surface of the planar ultrasonic transducer to the surface of the irradiated target area.

[0052] In this embodiment, the preset axial distance range corresponding to the near-field mode is 0-30mm, and the preset axial distance range corresponding to the far-field mode is greater than 30mm.

[0053] The method described in this embodiment also includes: After adjusting the axial distance, the output sound power fluctuation is monitored in real time by the sound power monitoring unit; Based on the fluctuation of the acoustic power, the output power of the ultrasound generator or the treatment parameters are dynamically adjusted to maintain a stable therapeutic acoustic power.

[0054] In this embodiment, the step of obtaining the sound field mode selection instruction is based on at least one of the following information: the type of the target organ, the estimated depth of the target organ, or the user's direct input.

[0055] The preset treatment parameters in this embodiment include a sound power of 2W, a pulse repetition frequency of 1kHz, and a duty cycle of 20%.

[0056] This embodiment employs differential sound field distance control: the core of which lies in actively utilizing the inherent physical characteristics of the sound field of a planar ultrasonic transducer. For a planar disk transducer with diameter D and frequency f, its sound field can be divided into a near field and a far field in terms of axial distance. The near field length N can be estimated using the formula: N ≈ D 2 f / (4c), where c is the speed of sound. In the near field region, the sound pressure distribution is complex, with multiple maxima and minima. The sound intensity is high but the uniformity is poor. In the far field region, the sound beam begins to diverge, the sound pressure decreases monotonically with distance, the sound intensity decreases but the distribution tends to be uniform.

[0057] The innovation of this embodiment lies in that it does not passively receive a sound field at a fixed distance, but rather actively and controllably adjusts the axial distance to precisely set the system to operate in a preset near-field or far-field mode. The near-field mode corresponds to a distance range of 0 to N, and its high sound intensity and strong mechanical effect make it suitable for treatment scenarios requiring high sound energy density and shallow target depths. The far-field mode corresponds to a distance range greater than N, and its good sound field uniformity and wide coverage make it suitable for treatment scenarios requiring uniform irradiation of large tissue areas and deeper target depths.

[0058] The preset axial distance range is an adjustment range determined based on the parameters of a typical therapeutic planar transducer and the aforementioned sound field theory, combined with the tissue sound attenuation characteristics and the clinical safety window.

[0059] In this embodiment, the control module implements a coordinated closed loop of mode command, distance adjustment, and parameter output. When the user or system selects near-field mode, the control module performs the following coordinated operations: 1. Send a command to the sound field adjustment module to precisely adjust the axial distance to the preset near field range (e.g., 5mm).

[0060] 2. Simultaneously, a set of adjusted near-field treatment parameters (e.g., relatively high acoustic power, specific pulse waveform) are called or configured to the ultrasound generator to match the characteristics of high near-field acoustic intensity, ensuring effectiveness while avoiding local overheating.

[0061] When far-field mode is selected, collaborative execution occurs: 3. Adjust the axial distance to the preset far-field range (e.g., 30mm).

[0062] 4. Call up or configure another set of adjusted far-field treatment parameters (e.g., use a longer pulse train or adjust the duty cycle to work with a uniform sound field) to ensure that sufficient sound energy can effectively reach the deep target area and achieve uniform coverage.

[0063] This modular, parameter-set-linked control strategy enables the system to not only operate at two different physical distances, but also to output therapeutic energy that best matches the characteristics of the corresponding sound field, thereby maximizing the treatment efficiency and safety in each mode.

[0064] 2. Effects of acoustic field distance differences on therapeutic efficacy in T2DM mice The liver and pancreas are important regulatory organs for blood glucose balance. In this study, LIPUS stimulation was performed on the hepatopancreatic region of mice for 35 days based on acoustic field distance differences to evaluate its regulatory effect on hyperglycemia.

[0065] like Figures 7-11The image shows the process and pathological changes in treating T2DM mice using acoustic field distance differentiation. Specifically: Figure 7 This diagram illustrates the grouping of mice with T2DM treated with differential acoustic field distance. Mice were divided into two groups: normal mice with shams (Normal group) and T2DM mice (T2DM group). The T2DM group was randomly divided into two subgroups: mice with T2DM with shams (Control group) and mice receiving ultrasound treatment (LIPUS group). Mice in the LIPUS group were randomly divided based on acoustic field distance into two subgroups: mice with T2DM treated with LIPUS at a acoustic field distance of 5 mm (LIPUS-5mm group) and mice with T2DM treated with LIPUS at a acoustic field distance of 30 mm (LIPUS-30mm group). Before LIPUS treatment, there were no significant differences in RBG among all T2DM groups. Mice receiving sham treatment did not produce LIPUS output during the experiment.

[0066] Figure 8 This is a schematic diagram illustrating fasting blood glucose changes in multiple control groups. It shows the changes in fasting blood glucose over 5 weeks in the Normal, Control, LIPUS-5mm, and LIPUS-30mm groups. Line graph analysis shows that FBG in the Control group mice continuously increased, while fasting blood glucose in the Normal group remained essentially unchanged. After LIPUS intervention, blood glucose levels in T2DM mice all decreased. The bar chart on the right shows the area under the curve (AUC) for each group of mice at week 5 of treatment. It reveals a significant difference in fasting blood glucose levels between the LIPUS group and the Control group at the end of treatment, with the LIPUS-30mm group showing a closer resemblance to normal mice.

[0067] Figure 9 This is a schematic diagram illustrating the changes in random blood glucose levels in a multi-group control experiment, showing the changes in random blood glucose levels in four groups of mice over a 35-day treatment period. Analysis of the line graph shows that random blood glucose levels remained at a high level in the Control group, remained essentially unchanged in the Normal group, and decreased in all mice after LIPUS intervention. Mice in the LIPUS-30mm group showed a more normal blood glucose level.

[0068] Figure 10-11 The effect of LIPUS on insulin resistance was assessed using insulin and glucose tolerance tests. The results of both tests showed significant differences between the treatment and control groups (p < 0.0001). This demonstrates that LIPUS improves insulin sensitivity and glucose metabolism, enhancing glycemic regulation in T2DM mice. Far-field LIPUS resulted in better metabolic homeostasis reconstruction in T2DM mice. Specifically: Figure 10This diagram illustrates the changes in blood glucose levels during an insulin test in a multi-group controlled experiment, reflecting the results of insulin sensitivity testing in four groups of mice at the end of treatment. The results show that blood glucose levels significantly decreased in the LIPUS treatment group 30 minutes after insulin injection, while there was no significant difference between the LIPUS-30mm group and the Normal group.

[0069] Figure 11 This diagram illustrates blood glucose changes during a glucose tolerance test in a multi-group controlled experiment. It shows the results of the glucose tolerance test in four groups of mice at the end of treatment. The results indicate that blood glucose levels in mice rose rapidly 15 minutes after glucose ingestion. The control group mice maintained a high level of random blood glucose. The LIPUS-5mm group showed a decreasing trend at 60 minutes, while the LIPUS-30mm group showed a decreasing trend at 30 minutes, similar to the Normal group.

[0070] 3. Detection Method The detection methods involved in the above examples are as follows: Blood tests: Blood was collected from the tail vein, and blood glucose concentration was measured using a glucometer. RBG was measured daily at 15:00. FBG was measured every Friday at 8:00 in mice that had been fasted for 12 hours.

[0071] Insulin and glucose tolerance tests: Mice were fasted for 12 hours before the glucose tolerance test and 6 hours before the insulin test. Mice were orally administered glucose solution (2 g / kg) for the glucose tolerance test and intraperitoneally injected with insulin solution (0.75 u / kg) for the insulin test. Fasting blood glucose was measured before glucose or insulin ingestion and recorded as the blood glucose value at min 0. After ingestion, blood glucose levels were measured and recorded at mins 15, 30, 60, 90, and 120. The area under the curve (AUC) was plotted.

[0072] Statistical analysis: Statistical analysis was performed using GraphPadPrism 9.0 (GraphPad Software, USA). Data are presented as mean ± standard deviation. The unpaired two-tailed student-test was used to assess differences between two groups, and two-way ANOVA was used to assess differences among multiple groups. Statistical significance was defined as p-value < 0.05.

[0073] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A planar ultrasonic transducer with adjustable sound field, comprising a planar ultrasonic transducer and a sound field adjustment device fixedly disposed on the radiating surface of the planar ultrasonic transducer, wherein the sound field adjustment device comprises an impedance matching layer, an acoustic diffusion layer, and a coupling pad; The impedance matching layer is disposed between the acoustic diffusion layer and the planar ultrasonic transducer to achieve acoustic impedance matching between the transducer and the target medium. The acoustic diffusion layer is disposed on the impedance matching layer and has multiple randomly distributed holes for scattering ultrasonic waves to improve the uniformity of the sound field. The coupling pad is disposed between the acoustic diffusion layer and the skin to adjust the impedance matching between the acoustic diffusion layer and the skin, and to adjust the axial distance between the planar ultrasonic transducer in the ultrasonic generator and the irradiation target area.

2. The planar ultrasonic transducer with adjustable sound field according to claim 1, characterized in that: The thickness of the coupling pad is configured such that when a coupling pad of a first thickness is used, the planar ultrasonic transducer operates in near-field mode; and when a coupling pad of a second thickness is used, the planar ultrasonic transducer operates in far-field mode, wherein the second thickness is greater than the first thickness.

3. The planar ultrasonic transducer with adjustable sound field according to claim 1, characterized in that: The impedance matching layer is an air cavity metamaterial matching layer, comprising a regularly arranged array of air cavities, wherein the diameter of the air cavities is 1 / 10 to 1 / 5 of the working wavelength and the depth is 1 / 4 of the working wavelength.

4. The planar ultrasonic transducer with adjustable sound field according to claim 1, characterized in that: The aperture of the pores in the acoustic diffusion layer is between 1 / 8 and 1 / 5 of the working wavelength; the pore depth is between 1 / 2 and 2 of the working wavelength; and the fill rate is between 30% and 50%.

5. An ultrasound therapy system, characterized in that, include: The planar ultrasonic transducer with adjustable sound field according to any one of claims 1 to 5; The control module, which is communicatively connected to the planar ultrasonic transducer, is used for: Receive or generate a sound field mode selection command, wherein the sound field mode includes at least a near-field mode and a far-field mode; The coupling pad is controlled to adjust the axial distance to a preset axial distance range corresponding to the selected sound field mode; The planar ultrasound transducer is controlled to operate according to preset treatment parameters at the preset axial distance.

6. The ultrasound therapy system according to claim 5, characterized in that, The control module includes an axial distance control unit for driving the planar ultrasonic transducer or the coupling pad to move to change the axial distance; the thickness of the coupling pad is replaceable or adjustable.

7. The ultrasound therapy system according to claim 6, characterized in that, The coupling pad includes a thin coupling pad for near-field mode, a thick coupling pad for far-field mode, or a liquid-fillable coupling cavity.

8. The ultrasound therapy system according to claim 5, characterized in that, The control module also includes: A parameter preset unit is used to set and store the treatment parameters, which include acoustic power, pulse repetition frequency, duty cycle and single treatment time. The real-time feedback unit is used to monitor the electrical power output by the planar ultrasonic transducer through an impedance matching circuit and provide feedback signals to the control module for dynamic adjustment.

9. The ultrasound therapy system according to claim 5, characterized in that, The control module is also configured to automatically adjust the thickness of the coupling pad or the emission parameters of the planar ultrasonic transducer based on the changes in electrical power monitored by the real-time feedback unit, so as to maintain the axial distance within the preset axial distance range.

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