Multi-frequency ultrasonic confocal treatment device and system and control method of multi-frequency ultrasonic confocal treatment device and system

Abstract

The invention provides a multi-frequency ultrasonic confocal treatment device and system and a control method of the multi-frequency ultrasonic confocal treatment device and system, and relates to the field of medical ultrasonic treatment. The energy focusing efficiency, the treatment depth control and the skin safety are remarkably improved. As the curvature radius of each single array element probe is strictly consistent with that of the concave base, the geometric positions of focuses can be ensured to be consistent no matter how the number and the arrangement mode of the probes change, and multi-frequency acoustic beams are converged in the same point space; the multi-channel frequency is combined to form a composite frequency confocal sound field, more uniform and higher energy density is generated at the same focus, and the sound field superposition efficiency is improved; quantitative and repeatable control of focus depth can be realized, multi-channel energy dynamic distribution improves treatment efficiency, duty ratio and time sequence cooperative control realizes surface safety protection, and skin temperature closed-loop control ensures real-time safety feedback.

Description

Technical Field

[0001] This invention relates to the field of medical ultrasound therapy technology, and in particular to a multi-frequency ultrasound confocal therapy device, system, and control method thereof. Background Technology

[0002] High-Intensity Focused Ultrasound (HIFU), a non-invasive thermal ablation and mechanical effect therapy, has been widely used in various fields such as benign and malignant tumors, prostate diseases, uterine fibroids, neuromodulation, and cosmetic medicine. Current focused ultrasound devices mainly employ a single-frequency focusing method, which concentrates energy but makes it difficult to simultaneously optimize penetration depth, cavitation effect, and heat distribution. When the tissue absorption coefficient changes with frequency, a single-frequency treatment mode often fails to meet the energy deposition needs of both deep and superficial tissues, thus affecting treatment efficiency and safety.

[0003] In existing technologies, multi-frequency ultrasound excitation has been proposed to improve energy distribution. For example, Chinese patent application CN102247661A, entitled "Method and Device for Non-invasive Liposuction Using Composite Frequency Focused Ultrasound," discloses a composite frequency focused ultrasound system for non-invasive liposuction. This technology uses multiple transducer units to emit ultrasound waves of different frequencies, forming a composite frequency sound field in the subcutaneous fat layer, thereby promoting fat cell rupture. However, this approach is mainly geared towards superficial tissue cosmetic applications, with a shallow focusing depth (typically less than 20 mm). The control method is mainly based on simple frequency superposition, without involving independent driving of different probes, synchronous phase control, or real-time feedback calibration mechanisms. Furthermore, the transducers in this device can be multi-element structures, making it difficult to achieve strict overlap of spatial focal points, thus failing to effectively form a high-energy-density hetero-frequency confocal sound field. Safety controls are also insufficient: some devices rely on deep temperature monitoring, increasing hardware complexity; and skin surface safety protection measures are inadequate.

[0004] For example, US Patent Application No. US5460595A, entitled Multi-frequency ultrasound therapy systems and methods, discloses a device that allows a single ultrasound head to switch between multiple frequencies, but it only operates in a single transducer frequency-tunable mode and does not achieve energy superposition through multi-probe confocaling.

[0005] Therefore, it is evident that existing multi-frequency ultrasound technologies mostly focus on single-probe variable frequency or multi-probe frequency superposition but non-confocal solutions, which still have the following shortcomings: The focal points of the sound beams emitted by multiple probes are difficult to strictly coincide in space, resulting in insufficient energy concentration; Frequency control is mostly static superposition, lacking real-time feedback and synchronous control mechanisms; The skin safety protection measures were not adequately explained, and there was a lack of closed-loop control based on skin temperature. The accuracy of the probe placement focus depends on a fixed position, making it difficult to flexibly expand the number and angle of probes.

[0006] Therefore, there is an urgent need for an ultrasound therapy device and method that can achieve precise confocal and synchronous control of multi-frequency single-element probes, so as to simultaneously optimize acoustic penetration depth and focused energy distribution, thereby improving treatment efficiency and safety. Summary of the Invention

[0007] To achieve the above-mentioned objectives and other advantages of the present invention, a first objective of the present invention is to provide a multi-frequency ultrasound confocal therapy device, comprising: Multiple single-element focusing probes, wherein the number of multiple single-element focusing probes is three or more, each probe is a spherical or annular focusing single-element transducer, and the radius of curvature of each probe is the same; A concave base has an inner surface radius of curvature that is consistent with the radius of curvature of the single-element focusing probe. Multiple single-element focusing probes are fixedly installed on the concave surface of the concave base, such that the geometric focus of each probe coincides in space with the central focus area of ​​the base. An adjustable water bag, installed at the front end of the concave base, is used to contain the acoustic coupling medium and contact the skin surface of the treatment area. The thickness of the adjustable water bag is adjusted by injecting or draining liquid. A skin temperature monitoring module is installed on the wall surface of the adjustable water bag that contacts the skin, for real-time monitoring of skin surface temperature; A multi-channel drive and synchronization control system is electrically connected to multiple single-element focusing probes, respectively, to provide independent drive signals for each probe and control each probe to emit synchronously or interleavedly at different operating frequencies; The main control processing unit is connected to the skin temperature monitoring module and the multi-channel drive and synchronization control system, respectively. It is used to execute the skin temperature closed-loop control algorithm and dynamically adjust the power and / or transmission timing of the multi-channel drive and synchronization control system output to each probe according to the temperature signal fed back by the skin temperature monitoring module.

[0008] Furthermore, the operating frequencies of the multiple single-element focusing probes are respectively , where n is the number of probes, and the ratio between each frequency is an integer ratio or a fractional ratio, so as to form a composite frequency sound field in the central focal region.

[0009] Furthermore, the skin temperature closed-loop control algorithm executed by the main control processing unit includes: Set a safe threshold for skin temperature ; Real-time acquisition of skin temperature measured by the skin temperature monitoring module ; Based on skin temperature Skin temperature safety threshold Based on the comparison results, the driving power of each probe is dynamically adjusted. The adjustment strategies include: when At the same time, maintain or output power according to the preset scheme; when At the same time, reduce the driving power of at least one high-frequency probe; when If necessary, immediately reduce the drive power of all probes or specific high-frequency probes, or suspend transmission; when When the power is restored to the preset value; in, , The preset warning temperature difference value, and .

[0010] Furthermore, the multi-channel drive and synchronization control system supports staggered transmission mode, enabling each probe to start or stop transmitting at different times, with the interval between the start times of adjacent probes being 1-5 milliseconds.

[0011] Furthermore, the outer wall of the adjustable water bladder is provided with a thickness scale, which is used to indicate the thickness of the water bladder according to the formula. Calculate or look up a table to determine the depth of focus within the organization ,in, The average speed of sound in the target organization. The velocity of sound in the coupling medium. For the thickness of the water bladder, The radius of curvature of the probe and the base.

[0012] Furthermore, the main control processing unit is also configured to dynamically allocate power weights to each probe according to the target treatment depth and treatment plan. The allocation principle is as follows: within the safe temperature range, the power weight of low-frequency probes is increased first to enhance the penetration depth; when the skin temperature is close to the safe threshold, the power weight of high-frequency probes is decreased first to control the surface heat load.

[0013] A second objective of this invention is to provide a control method for a multi-frequency ultrasound confocal therapy device, employing the aforementioned multi-frequency ultrasound confocal therapy device, wherein the method includes the following steps: Receive the focal depth setting parameters, adjust the thickness of the adjustable water bag according to the focal depth setting parameters, and configure the working frequency and initial drive parameters of each single-element focusing probe; The multi-channel drive and synchronization control system controls the multiple single-element focusing probes to emit ultrasonic waves at different configured working frequencies, so that the sound beams emitted by each probe converge and superimpose in the central focal region of the concave base. The system receives a temperature feedback signal from the skin temperature monitoring module, compares the temperature feedback signal with a preset temperature threshold, and dynamically adjusts the drive power and / or transmission timing output to at least one probe based on the comparison result.

[0014] Furthermore, configuring the initial driving parameters for each single-element focusing probe includes: assigning an initial power weight to each probe; wherein probes with lower operating frequencies are assigned a higher initial power weight, and / or probes with higher operating frequencies are assigned a lower initial power weight.

[0015] Furthermore, the control system for the multi-channel drive and synchronization control drives the probe in an interleaved emission mode, so that the ultrasonic pulses emitted by different probes are partially staggered in time; wherein the start time interval between adjacent probe pulses is 1-5 milliseconds.

[0016] A third objective of this invention is to provide a multi-frequency ultrasound confocal therapy system, comprising the aforementioned multi-frequency ultrasound confocal therapy device, as well as an image guidance device and a treatment planning unit; The image-guided device is used to acquire anatomical images of the treatment area in real time or preoperatively to assist in localization; The treatment planning unit is communicatively connected to the main control processing unit and is used to generate a treatment parameter scheme including the target focal depth, frequency combination of each probe, initial power allocation and safe temperature threshold according to the image information and treatment target obtained by the image guidance device, and send it to the main control processing unit for execution.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention, by introducing a synergistic mechanism of precise geometric registration, adjustable depth of focus, and closed-loop power control based on a multi-frequency ultrasound confocal structure, achieves significant improvements in energy focusing efficiency, treatment depth control, and skin safety. Compared with existing technologies, it has the following comprehensive technical advantages: This invention achieves a significant improvement in focus consistency and energy superposition accuracy: because the radius of curvature of each single-element probe is strictly consistent with the concave base, the geometric position of the focus can be guaranteed regardless of the number and arrangement of the probes, thus enabling the convergence of multi-frequency sound beams in the same point of space; Multi-channel frequency combination It forms a composite frequency confocal sound field, producing a more uniform and higher energy density at the same focal point, improving the sound field superposition efficiency and reducing sidelobe energy leakage; Experimental results from an external water tank show that the peak sound pressure level at the focal point of the multi-frequency confocal method is about 30-50% higher than that of the single-frequency method with the same power, the focal volume is reduced by about 20%, and the sound field distribution is more concentrated.

[0018] This invention achieves quantitative and repeatable control of focal depth: it employs a concave base matching the probe curvature and an adjustable water bladder structure, and achieves focal depth through calibrated thickness adjustment. Predictable changes; Based on the principle of sound path equivalence, the thickness of the water bladder can be used to determine this. Precisely calculate the depth of focus to achieve millimeter-level repeatable control; Experimental verification shows that when the thickness of the water bladder changes by 1 mm, the focal depth changes by about 1.04 mm, with an error of less than ±5% compared with the theoretical calculation.

[0019] This invention achieves dynamic multi-channel energy allocation to improve treatment efficiency: a power weight allocation algorithm based on frequency characteristics and skin temperature feedback can adaptively adjust the proportion of low-frequency and high-frequency energy at different treatment depths; In deep treatment mode, the system automatically increases the power weight of the low-frequency channel to enhance penetration; in superficial treatment or when skin temperature rises, it automatically reduces the power of the high-frequency channel to control surface heat load. Compared to traditional fixed power output methods, the dynamic distribution strategy of this invention can reduce the skin surface temperature rise by about 2–3°C while ensuring that the acoustic energy in the focal zone remains unchanged.

[0020] This invention achieves surface safety protection through coordinated control of duty cycle and timing: by using a closed-loop temperature monitoring signal, the system adjusts the duty cycle and emission timing of each probe in real time to achieve multi-channel interleaved emission and avoid the instantaneous energy of all probes from being superimposed on the skin surface; When the skin temperature enters the warning zone, the high-frequency channel automatically reduces the duty cycle or pauses transmission, while the low-frequency channel maintains output to keep the focus energy stable. This strategy can significantly reduce heat buildup on the skin, prevent overheating and burns, and ensure that the skin temperature is always below a safe threshold.

[0021] This invention achieves closed-loop control of skin temperature to ensure real-time safety feedback: the system has a built-in high-speed temperature sampling and power closed-loop adjustment algorithm (control cycle 100-200ms), which can reduce power immediately when the skin temperature exceeds the upper limit and gradually restore output after the temperature recovers; Compared to open-loop control systems, the closed-loop algorithm of this invention can control the temperature over-limit response time within 0.2s in experiments, effectively avoiding local overheating.

[0022] This invention achieves comprehensive performance advantages and scalability: the device structure is modular, the number of probes can be expanded, and it can adapt to different treatment areas and tissue depth requirements; Control strategies and feedback mechanisms can be configured through software parameters to switch between different treatment modes; The overall system balances focusing intensity, temperature safety, and control precision, and has good clinical adaptability and industrial feasibility.

[0023] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Specific embodiments of the present invention are given in detail below with reference to the accompanying drawings. Attached Figure Description

[0024] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a block diagram illustrating the principle of a multi-frequency ultrasound confocal therapy device. Figure 2 This is a side view of the transducer; Figure 3 This is a bottom view of the transducer; Figure 4 This is a flowchart of the control method for a multi-frequency ultrasound confocal therapy device. Detailed Implementation

[0025] The present invention will now be further described with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0026] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

[0027] The drawing numbers in this application are only used to distinguish the steps in the scheme and are not used to limit the execution order of the steps. The specific execution order is as described in the specification.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0029] This invention aims to overcome the above-mentioned problems and provides a multi-frequency ultrasound confocal therapy device, system, and method, achieving flexible focus control, adjustable depth, focal zone energy superposition, and skin temperature safety protection. The specific solution is as follows: Example 1 A multi-frequency ultrasound confocal therapy device, such as Figures 1-3 As shown, the device 100 includes: Multiple single-element focusing probes (101), the number of which is three or more, each probe is a spherical or annular focusing single-element transducer, and the radius of curvature R of each probe is the same, thereby ensuring that the focus coincides; The concave base (102) has an inner surface radius of curvature that is consistent with the radius of curvature R of the single-element focusing probe (101). Multiple single-element focusing probes (101) are fixedly installed on the concave surface of the concave base (102), so that the geometric focus of each probe coincides in space with the central focus area (F) of the base; that is, each probe is embedded in the concave surface of the base to ensure that its geometric focus coincides with the central focus area (F) of the base. Figure 3 Multi-frequency spherical or annular single-element probes are nested layer by layer, such as the first single-element focusing probe 1011, the second single-element focusing probe 1012, and the third single-element focusing probe 1013 nested layer by layer.

[0030] An adjustable water bladder (103), mounted on the front end of the concave base (102), is used to contain an acoustic coupling medium (such as deaerated water, saline, or acoustic gel) and to contact the skin surface of the treatment area. The thickness of the adjustable water bladder (103) can be adjusted by injecting or draining liquid, and the thickness scale corresponds to the distance from the transducer emitting surface to the skin surface. ; A skin temperature monitoring module (105) is installed on the wall surface of the adjustable water bladder (103) that contacts the skin, for real-time monitoring of skin surface temperature; it can use a patch thermocouple, infrared temperature sensor, or fiber optic temperature sensor (for dynamic response). Sensing accuracy ±0.2°C, response time <200ms.

[0031] The multi-channel drive and synchronization control system (104) is electrically connected to the multiple single-element focusing probes (101) respectively, and is used to provide an independent drive signal for each probe and control each probe to transmit synchronously or interleavedly at different operating frequencies; specifically, the multi-channel drive and synchronization control system provides an independent frequency, phase and power channel for each probe, supports multi-frequency synchronous or interleaved transmission, and can be dynamically adjusted according to the feedback signal; The main control processing unit (106) is connected to the skin temperature monitoring module (105) and the multi-channel drive and synchronization control system (104) respectively. It is used to execute the skin temperature closed-loop control algorithm and dynamically adjust the power and / or transmission timing of the multi-channel drive and synchronization control system (104) output to each probe according to the temperature signal fed back by the skin temperature monitoring module (105).

[0032] In this embodiment, the main control processing unit executes a control algorithm to coordinate the multi-frequency confocal output and automatically adjusts the power ratio and phase synchronization of each probe based on feedback. The operating frequencies of each single-element focusing probe are as follows: Where n is the number of probes, and the ratio between each frequency is an integer ratio or a fractional ratio (e.g., 1:1.5:2), to form a composite frequency sound field in the central focal region (F) to achieve energy superposition at different depths. A skin temperature closed-loop control algorithm is executed to dynamically adjust the power and duty cycle of each probe to ensure surface safety.

[0033] In this embodiment, the main control processing unit is used to receive skin temperature sensor signals, execute a closed-loop power control algorithm, and interact with the drive module, human-machine interface, and log recording module. Specifically, the skin temperature closed-loop control algorithm executed by the main control processing unit (106) includes: Set a safe threshold for skin temperature The control objective is to maintain skin temperature. Not exceeding the preset upper limit (Typically 42°C); Real-time acquisition of skin temperature measured by the skin temperature monitoring module (105) ; Based on skin temperature Skin temperature safety threshold Based on the comparison results, the driving power of each probe is dynamically adjusted. The adjustment strategies include: Safe zone: when At the same time, maintain or output power according to a preset scheme; for example, when At that time, normal power output; Warning zone: When When this is the case, reduce the drive power of at least one high-frequency probe; for example, when At this time, slightly reduce the power or maintain the power to avoid further increase; Danger zone: When If necessary, immediately reduce the drive power of all probes or specific high-frequency probes, or pause transmission; for example, immediately reduce the power of high-frequency probes by 50% or pause transmission for several milliseconds. Recovery area: when When the power is restored to the preset value; for example, when The power slowly recovers to the preset value.

[0034] in, , The preset warning temperature difference value, and .

[0035] In this embodiment, the power adjustment and timing prioritize the adjustment of the high-frequency probe power, while the low-frequency probe power is maintained or adjusted slowly; it supports interleaved transmission mode (1–5ms window) to reduce instantaneous surface load; and the control period is 100–200ms.

[0036] In this embodiment, the multi-channel drive and amplification module provides an independent power control channel for each single-element focusing probe, which can adjust the output power and duty cycle, support multi-frequency synchronous or interleaved transmission modes, and enable each probe to start or stop transmitting at different time points. The interval between the start times of adjacent probes is 1-5 milliseconds, reducing instantaneous surface load.

[0037] In this embodiment, the skin temperature monitoring module includes at least one to three temperature sensors located at the point where the outer wall of the water bladder contacts the skin; the optional sensor types include thermocouples, infrared sensors, and fiber optic temperature sensors; the real-time sampling frequency is ≥10Hz, the measurement accuracy is ±0.2°C, and the response time is <200ms.

[0038] In this embodiment, the outer wall of the adjustable water bladder (103) is provided with a thickness scale, which is used to indicate the thickness of the water bladder so as to determine the depth of the focal point in the tissue by calculation or table lookup. .

[0039] Specifically, to accommodate different treatment depths, this invention utilizes the thickness of the water-filled bladder. Adjust the focal point within the tissue. Based on the principle of sound path equivalence, when the transducer is designed with a focal length of R, in water (velocity of sound... ) and organization (speed of sound) In a layered medium, when a sound beam is incident perpendicularly along the axial direction, the focal point is at a depth relative to the skin surface. It can be approximated as: in, The average sound velocity of the target tissue (approximately 1540 m / s for soft tissue). The velocity of sound in the coupling medium, such as the velocity of sound in water (approximately 1480 m / s). The thickness of the water bladder is in mm. The radius of curvature (mm) is the radius of curvature of the probe and the base.

[0040] The water bladder can be directly read by setting graduations (in mm) on its outer wall. The focal depth is calculated based on the above formula or by looking up a table, thereby achieving quantitative and repeatable depth control.

[0041] The treatment transducer excitation automatically stops when the temperature sensor malfunctions or fails; if the skin temperature sensor detects overheating, it needs to be cooled to a safe zone to recover. <38°C).

[0042] In this embodiment, the main control processing unit (106) is also configured to dynamically allocate power weights to each probe according to the target treatment depth and treatment plan. The allocation principle is as follows: within the safe temperature range, the power weight of low-frequency probes is increased first to enhance the penetration depth; when the skin temperature is close to the safe threshold, the power weight of high-frequency probes is reduced first to control the surface heat load.

[0043] Specifically, since the acoustic penetration capability and surface absorption characteristics of multi-frequency probes differ, the main control unit employs a power weighting allocation mechanism for each probe to balance deep energy deposition and surface temperature rise control. This mechanism dynamically determines the power weighting coefficient of each channel based on the following factors: the probe's operating frequency and corresponding acoustic attenuation characteristics; the probe's position and incident angle on the concave base; and real-time skin temperature feedback and the status of the safe zone.

[0044] Power allocation satisfies: in, For total output acoustic power, Let i be the acoustic power of the i-th probe. Weights are assigned to them. Within the normal safe zone, low-frequency probes can be assigned higher power to enhance penetration; when the temperature approaches the threshold, the weight of high-frequency probes is automatically reduced, thereby reducing surface acoustic energy density and ensuring skin safety.

[0045] This invention provides a multi-frequency ultrasound therapy device, system, and control method that utilizes multiple single-element focusing probes of different frequencies to form a confocal sound field in the same focal region. It is suitable for non-invasive treatment of tumor ablation, neuromodulation, drug release, and other deep tissues.

[0046] This invention achieves focal point co-focusing through ≥3 single-element focusing probes, ensuring high precision in focal point overlap; it enables quantitative adjustment of focal depth using an adjustable water-filled coupling medium; it ensures treatment safety and avoids surface overheating based on closed-loop skin temperature control; it improves the energy superposition efficiency of the focal zone, balancing safety and treatment effectiveness; and it provides complete treatment operation procedures for easy implementation and repetition.

[0047] Example 2 A control method for a multi-frequency ultrasound confocal therapy device is provided, employing the aforementioned multi-frequency ultrasound confocal therapy device. For a detailed description of the device, please refer to the corresponding description in the above device embodiments; it will not be repeated here. Figure 4 As shown, the method includes the following steps: S1. Parameter setting steps: Receive the focus depth setting parameters, adjust the thickness of the adjustable water bag according to the focus depth setting parameters, and configure the working frequency and initial drive parameters of each single-element focusing probe to ensure that the focus coincides to form a composite frequency sound field. When using this control method for multi-frequency ultrasound confocal therapy, the treatment target needs to be located first: the treatment target area and tissue depth are determined by ultrasound, CT, MRI or other imaging examinations; a scale is set on the water bag to determine the distance from the lower edge of the base to the skin surface, thereby calculating the depth of the focal point under the skin.

[0048] To achieve energy superposition of multi-frequency ultrasound at the same focal point while ensuring skin surface safety, this embodiment proposes an acoustic energy control strategy based on target acoustic power setting, dynamic allocation of channel power, and coordinated adjustment of duty cycle and timing.

[0049] The main control processing unit sets the acoustic power or acoustic energy density of the target focal area according to the treatment plan or preset parameters. This target can be adjusted according to the treatment type, such as tissue ablation, functional modulation, or transdermal assistance. The control system calculates the output reference values ​​of each transmission channel accordingly to ensure that the sound field intensity in the focal area reaches the predetermined level.

[0050] At different treatment depths, the control system automatically matches the frequency combination and power ratio to achieve spatial consistency of the target acoustic energy density. When the skin temperature feedback approaches the safe threshold, the system automatically reduces the overall output power or adjusts the energy distribution strategy.

[0051] Therefore, in the parameter setting step, configuring the initial driving parameters of each single-element focusing probe includes: assigning an initial power weight to each probe; wherein, probes with lower operating frequencies are assigned a higher initial power weight, and / or probes with higher operating frequencies are assigned a lower initial power weight.

[0052] Specifically, since the acoustic penetration capability and surface absorption characteristics of multi-frequency probes differ, the main control unit employs a power weighting allocation mechanism for each probe to balance deep energy deposition and surface temperature rise control. This mechanism dynamically determines the power weighting coefficient of each channel based on the following factors: the probe's operating frequency and corresponding acoustic attenuation characteristics; the probe's position and incident angle on the concave base; and real-time skin temperature feedback and the status of the safe zone.

[0053] Power allocation satisfies: in, For total output acoustic power, Let i be the acoustic power of the i-th probe. Weights are assigned to them. Within the normal safe zone, low-frequency probes can be assigned higher power to enhance penetration; when the temperature approaches the threshold, the weight of high-frequency probes is automatically reduced, thereby reducing surface acoustic energy density and ensuring skin safety.

[0054] S2, Sound field generation step: Control the multi-channel drive and synchronization control system to drive the multiple single-element focusing probes to emit ultrasonic waves at different configured working frequencies, so that the sound beams emitted by each probe converge and superimpose in the central focal area of ​​the concave base; Specifically, the multi-channel drive and synchronization control system is activated, and the power and duty cycle are initialized. The probes are driven to emit multi-frequency focused ultrasonic waves according to the set phase synchronization, and the continuous emission or staggered emission mode can be selected.

[0055] The emission duty cycle and emission sequence of each probe are uniformly scheduled by the main control system. The control algorithm adjusts the duty cycle and emission timing mode of each channel in real time based on the closed-loop skin temperature signal. When the temperature is in the safe zone, the system adopts a synchronous emission mode to enhance the focal area superposition effect; when the temperature enters the warning zone or danger zone, the system automatically switches to an interleaved emission mode to reduce the instantaneous surface energy superposition.

[0056] The duty cycle adjustment range is preferably 5%–50%, and the control cycle is 100–200ms. The emission times between multiple channels can be staggered by 1–5ms to reduce surface acoustic pressure peaks. The control system performs real-time closed-loop adjustments to the duty cycle, phase synchronization, and emission timing to achieve balanced energy output under different skin conditions.

[0057] Therefore, in the sound field generation step, the multi-channel drive and synchronization control system is controlled to drive the probe in an interleaved emission mode, so that the ultrasonic pulses emitted by different probes are partially staggered in time; wherein, the starting time interval between adjacent probe pulses is 1-5 milliseconds.

[0058] The multi-channel drive and synchronization control system is based on the target acoustic power of each channel. By combining the transducer's acoustic-to-electrical conversion efficiency and impedance, the required electrical power and driving voltage are calculated, and the corresponding levels are output by the multi-channel power amplifier module. The main control unit periodically reads the current and voltage data of the driving module and monitors the transducer load status in real time to prevent abnormal heating or impedance drift from causing sound field shift.

[0059] A multi-frequency superimposed focal point is formed in the target treatment area, and the energy in the focal zone is fully concentrated to achieve the expected treatment; the water-filled coupling medium ensures the transmission of sound waves, and the depth can be precisely controlled by adjusting the thickness of the water-filled bag.

[0060] S3. Closed-loop adjustment step: Receive the temperature feedback signal from the skin temperature monitoring module, compare the temperature feedback signal with the preset temperature threshold, and dynamically adjust the drive power and / or transmission timing output to at least one probe according to the comparison result.

[0061] Specifically, it collects skin temperature signals in real time; dynamically adjusts the power, duty cycle, and emission sequence of each probe according to safety thresholds; automatically reduces power or briefly pauses emission in temperature warning or danger zones, and resumes treatment after safe recovery.

[0062] The control system continuously maintains power distribution and timing adjustment to ensure stable focal energy; the treatment time is determined by the preset dose or treatment plan until the expected treatment effect is achieved.

[0063] In some closed-loop skin temperature control embodiments, three single-element probes with a curvature of 60 mm and frequencies of 0.8, 1.2, and 1.8 MHz were used. The water bladder thickness was 10 mm, the control period was 200 ms, and the upper limit of skin temperature was 42°C. Comparative experimental data on skin temperature response under different control modes are shown in Table 1.

[0064] Table 1. Comparison of skin temperature response under different control modes. In some embodiments of the system parameters and transmission strategies of multi-frequency confocal ultrasound therapy devices, the probe configuration is as follows: In this embodiment, the multi-frequency confocal ultrasound therapy device includes three single-element focusing transducers (numbered CH1, CH2, and CH3), and their parameters are shown in Table 2: Table 2. Transducer channel configuration and performance parameters in the embodiments Drive and power configuration: The system employs a multi-channel power amplifier, with each channel's output voltage amplitude and duty cycle independently adjustable. The system's total power is set to 24W (DC input power). Based on the probe frequency and electro-acoustic conversion efficiency, the acoustic power weights are allocated as shown in Table 3. Table 3. Multi-channel power allocation strategy and calculation results in the embodiments. Transmission duty cycle and timing strategy: Each probe uses a pulse duty cycle of CH1: 60%, CH2: 50%, CH3: 40%, with a period of T=10ms (equivalent transmission frequency 100Hz); the phase synchronization center of each channel is aligned with the focus (phase difference <10°), and an interleaved transmission mode is adopted: the initial phase of adjacent channels is staggered by 1–2ms to reduce the instantaneous superimposed heat load on the skin surface.

[0065] Skin temperature closed-loop regulation process: The skin temperature sensor samples at a real-time frequency of 10Hz; an upper temperature limit is set. =42°C; the control algorithm execution cycle is 200ms, when At ≥41°C, the following strategies are automatically implemented: reduce the power of the CH3 (2MHz) channel by 50%; if the temperature continues to rise to 42°C, pause the transmission of CH2 and CH3 for 500ms; when the temperature recovers to below 38°C, the power is linearly restored. In experimental verification, the skin surface temperature rise did not exceed 41.5°C, and the system response delay was <0.3s.

[0066] Sound field testing and treatment results (in vitro experiment): A 1mm acoustic focusing probe was placed in a degassed water tank, and the peak sound pressure level at the focal point was measured: Under multi-frequency confocal conditions: =2.1MPa; When a single-frequency 1MHz probe transmits alone: =1.4MPa; an increase of approximately 50%. The equivalent sound intensity I = p^2 / (2ρc) is calculated to be I≈1.43kW / cm2, which meets the coagulation threshold requirement of typical tissue (approximately 1kW / cm²).

[0067] Example 3 A multi-frequency ultrasound confocal therapy system includes the aforementioned multi-frequency ultrasound confocal therapy device, as well as an image guidance device and a treatment planning unit; for a detailed description of the device, please refer to the corresponding description in the above device embodiments, which will not be repeated here.

[0068] The image-guided device is used to acquire anatomical images of the treatment area in real time or preoperatively to assist in localization; The treatment planning unit is communicatively connected to the main control processing unit (106) and is used to generate a treatment parameter scheme including target focal depth, frequency combination of each probe, initial power allocation and safe temperature threshold according to the image information and treatment target obtained by the image guidance device, and send it to the main control processing unit (106) for execution.

[0069] The number of devices and processing scale described herein are for the purpose of simplifying the description of the invention. Applications, modifications, and variations of the invention will be readily apparent to those skilled in the art.

[0070] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

[0071] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0072] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0073] The above description is merely an embodiment of this specification and is not intended to limit the scope of one or more embodiments of this specification. Various modifications and variations can be made to one or more embodiments of this specification by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of one or more embodiments of this specification should be included within the scope of the claims of one or more embodiments of this specification.

Claims

1. A multi-frequency ultrasonic confocal treatment device, characterized in that, The application relates to a multi-frequency ultrasonic confocal treatment device, comprising: a plurality of single-array focusing probes, the number of the single-array focusing probes being three or more, each probe being a spherical or annular focusing single-array transducer, and the curvature radius of each probe being the same; a concave base, the inner surface curvature radius of the concave base being consistent with the curvature radius of the single-array focusing probes, the plurality of single-array focusing probes being fixedly installed on the concave surface of the concave base, and the geometric focal points of the probes being overlapped in space on a central focal point area of the base; an adjustable water bag installed at the front end of the concave base, used for containing an acoustic coupling medium and being in contact with the skin surface of a treatment area, the thickness of the adjustable water bag being adjusted by injecting or discharging liquid; a skin temperature monitoring module arranged on the wall of the adjustable water bag in contact with the skin, used for monitoring the skin surface temperature in real time; a multi-channel driving and synchronous control system electrically connected with the plurality of single-array focusing probes, used for providing independent driving signals for each probe and controlling the probes to synchronously or staggeredly emit at different working frequencies; a master control processing unit connected with the skin temperature monitoring module and the multi-channel driving and synchronous control system, used for executing a skin temperature closed-loop control algorithm and dynamically adjusting the power output to each probe and / or the emission timing sequence of the multi-channel driving and synchronous control system according to the temperature signal fed back by the skin temperature monitoring module.

2. A multi-frequency ultrasonic confocal treatment device according to claim 1, characterized in that, The working frequencies of the plurality of single-element focusing probes are respectively wherein n is the number of probes, and the ratio between each frequency is an integer ratio or a fractional ratio, so as to form a composite frequency sound field in the central focal point area.

3. A multi-frequency ultrasound confocal treatment device according to claim 1 or 2, characterized in that, The skin temperature closed-loop control algorithm executed by the master control processing unit comprises: Setting a skin temperature safety threshold ; acquiring in real time a skin temperature measured by the skin temperature monitoring module ; According to the comparison result of the skin temperature with the skin temperature safety threshold , the driving power of each probe is dynamically adjusted, and the adjustment strategy includes: When the power is maintained or output according to a preset scheme; When the driving power of at least one high frequency probe is reduced; When the driving power of all probes or specific high-frequency probes is immediately reduced, or transmission is suspended; When power is restored to the preset value; wherein, , is a preset early warning temperature difference, and .

4. A multi-frequency ultrasonic confocal treatment device according to claim 1, characterized in that, the multi-channel driving and synchronous control system supports a staggered emission mode, each probe starts or stops emitting at different time points, and the interval between the emission start times of adjacent probes is 1-5 milliseconds.

5. A multi-frequency ultrasonic confocal treatment device according to claim 1, characterized in that, The outer wall of the adjustable water bag is provided with a thickness scale for indicating the water bag thickness to calculate or look up the depth of the focal point in the tissue according to the formula calculating or looking up the depth of the focal point in the tissue according to the formula wherein, is the average sound speed of the target tissue, is the sound speed of the coupling medium, is the water bag thickness, is the radius of curvature of the probe and the base.

6. A multi-frequency ultrasonic confocal treatment device according to claim 1, characterized in that, The master control processing unit is further configured to dynamically allocate power weights to each probe according to a target treatment depth and a treatment scheme, and the allocation principle is that, within a safe temperature range, the power weight of a low-frequency probe is preferentially increased to enhance the penetration depth, and when the skin temperature approaches a safety threshold, the power weight of a high-frequency probe is preferentially reduced to control the surface heat load.

7. A method of controlling a multi-frequency ultrasonic confocal treatment device, characterized in that, The method comprises the following steps: receiving a focal point depth setting parameter, adjusting the thickness of the adjustable water bag according to the focal point depth setting parameter, and configuring the working frequencies and initial driving parameters of the single-array focusing probes; controlling the multi-channel driving and synchronous control system to drive the plurality of single-array focusing probes to emit ultrasonic waves at the configured different working frequencies, so that the sound beams emitted by the probes converge and superimpose in the central focal point area of the concave base; receiving a temperature feedback signal from the skin temperature monitoring module, comparing the temperature feedback signal with a preset temperature threshold, and dynamically adjusting the driving power output to at least one probe and / or the emission timing sequence according to the comparison result.

8. The method of claim 7, wherein the method further comprises: The configuration of the initial driving parameters of the single-array focusing probes comprises: allocating initial power weights to each probe, wherein a probe with a lower working frequency is allocated a higher initial power weight, and / or a probe with a higher working frequency is allocated a lower initial power weight.

9. The control method for a multi-frequency ultrasound confocal therapy device as described in claim 7, characterized in that, The control system is controlled to drive the probes in an interleaved transmission mode, so that the ultrasound pulses emitted by different probes are partially staggered in time, and the interval between the start times of adjacent probe pulses is 1-5 milliseconds.

10. A multi-frequency ultrasound confocal treatment system, characterized in that, The multi-frequency ultrasound confocal treatment device comprises the multi-channel driving and synchronization control system according to any one of claims 1-6, an image guidance device and a treatment planning unit. The image guidance device is used to acquire an anatomical image of a treatment region in real time or preoperatively to assist positioning. The treatment planning unit is in communication connection with the main control processing unit, and is used to generate a treatment parameter scheme containing a target focal point depth, a frequency combination of each probe, an initial power distribution and a safety temperature threshold according to image information acquired by the image guidance device and a treatment target, and send the treatment parameter scheme to the main control processing unit for execution.

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