Method and system for controlling focused ultrasound energy output

Abstract

The invention discloses a method and system for controlling focused ultrasound energy output, called CFUS for short, by calculating a resistance value of a load between two electrodes and setting a resistance threshold value, when the resistance value of the load is smaller than the resistance threshold value, focused ultrasound energy is allowed to be emitted to the electrodes; whether the load is in a heated state or not and the heating degree can be more accurately judged by detecting the resistance value of the load, so that quick response can be achieved, and the protection effect is achieved. The situation that the load is damaged by energy due to misoperation when focused ultrasound is used can be avoided; ultrasonic energy can be released as far as possible under the condition that safety is guaranteed, and unnecessary damage caused by excessive energy release is avoided; and different threshold values can be set based on different impedance conditions to meet different energy requirements.

Description

Technical Field

[0001] This invention relates to the field of combined electrical impedance signal measurement and ultrasonic composite control technology. Background Technology

[0002] Converging ultrasound is mainly divided into three types: high-intensity focused ultrasound (HIFU), micro-focused ultrasound (MSU), and low-intensity focused ultrasound (HIFU), primarily classified according to their energy levels. Regardless of the type, improper use of focused ultrasound can lead to unpredictable damage. Focused ultrasound technology is currently used in the medical field, where it acts on subcutaneous tissue to destroy fat cells, achieving localized fat reduction or wrinkle removal and tightening.

[0003] When using focused ultrasound, it is important to continuously change the location of the ultrasound energy output to diffuse the energy output area and avoid energy accumulation. Excessive energy or repeated outputs at the same location can lead to overly high energy levels at that location, potentially causing burns to the skin.

[0004] Chinese Patent CN114949640B discloses a method for controlling the output of ultrasonic energy, which determines the energy output by the moving speed of the ultrasonic therapy probe and the temperature of the body surface. While this technical solution can determine and control energy output based on the moving speed, it cannot solve the problem of energy accumulation. Using body surface temperature can only be used as a maximum value to determine whether energy is emitted, and it also cannot detect energy accumulation. Furthermore, the temperature transmission lag is significant, and it cannot prevent burns.

[0005] Therefore, a new technical solution is needed to address the above problems. Summary of the Invention

[0006] Purpose of the invention: This invention provides a method for controlling the energy output of focused ultrasound, in order to solve the problem of how to accurately determine and control the ultrasound energy output.

[0007] For the same purpose, the present invention also provides a system for controlling the energy output of focused ultrasound.

[0008] Technical Solution: To solve the above-mentioned technical problems, the method for controlling focused ultrasound energy output provided by the present invention adopts the following technical solution:

[0009] A method for controlling focused ultrasound energy output includes calculating the resistance value of a load between two electrodes; setting a resistance threshold such that focused ultrasound energy is allowed to be emitted to the electrodes when the resistance value of the load is less than the resistance threshold.

[0010] Furthermore, multiple electrodes are provided, with loads between each adjacent electrode, and the resistance values ​​of all loads are less than the resistance threshold, allowing focused ultrasound energy to be emitted to each electrode.

[0011] Furthermore, after connecting the load between the two electrodes, the voltage across the load and the current flowing through the load are calculated, and the resistance value of the load is calculated using the voltage and current.

[0012] Furthermore, a current transformer is connected in series with the electrodes to collect the voltage value V across the secondary side of the current transformer. Simple_A With V Simple_B The current I1 flowing through the two ends of the secondary side of the current transformer;

[0013] The voltage V0 across the load and the current I0 flowing through the load are calculated using the following formula.

[0014] I0 = N1 * I1, V0 = N2 * V1;

[0015] Where, V1=(V Simple_A +V Simple_B N1 is the turns ratio of the primary and secondary sides of the current transformer, and N2 is the turns ratio of the primary and secondary sides of the voltage transformer.

[0016] The load resistance R between the two electrodes A-B =V0 / I0.

[0017] Corresponding to the above method, the present invention also provides a system for controlling the energy output of focused ultrasound, comprising:

[0018] At least two electrodes, a host computer, used to obtain the resistance value of the load between the two electrodes and set the resistance threshold, and an ultrasonic transducer, used to emit focused ultrasonic energy; when the resistance value of the load is less than the resistance threshold, the host computer allows the ultrasonic transducer to emit focused ultrasonic energy to the electrodes.

[0019] Furthermore, the ultrasonic transducer is connected to multiple electrodes, and there is a load between each pair of adjacent electrodes. When the resistance value of all loads is less than the resistance threshold, the host computer allows the ultrasonic transducer to emit focused ultrasonic energy to each electrode.

[0020] Furthermore, after connecting the load between the two electrodes, the host computer calculates the voltage across the load and the current flowing through the load, and calculates the resistance value of the load based on the voltage and current.

[0021] Furthermore, it also includes an impedance detection circuit, which comprises: a current transformer, a first sampling resistor connected in series with one end of the current transformer, a second sampling resistor connected in series with one end of the current transformer, a third sampling resistor connected in parallel with the secondary side of the current transformer, and an AD sampling chip. The AD sampling chip acquires the voltage value V across the secondary side of the current transformer. Simple_A With V Simple_B Through voltage value V Simple_A With V Simple_BThe current I1 flowing through the secondary side of the current transformer is calculated by comparing it with the resistance values ​​of the first, second, and third sampling resistors respectively.

[0022] The voltage V0 across the load and the current I0 flowing through the load are calculated using the following formula.

[0023] I0 = N1 * I1, V0 = N2 * V1;

[0024] Where, V1=(V Simple_A +V Simple_B N1 is the turns ratio of the primary and secondary sides of the current transformer, and N2 is the turns ratio of the primary and secondary sides of the voltage transformer.

[0025] The load resistance R between the two electrodes A-B =V0 / I0.

[0026] Beneficial Effects: Compared with existing technologies, this invention stops energy emission if the impedance measurement value exceeds a threshold in the same load area. This ensures the emitted energy while preventing burns. Since heat transfer takes time and temperature cannot be quickly measured, and the load impedance changes with heat, detecting the load resistance allows for a more accurate assessment of whether and to what extent the load is heated. This enables a rapid response and protective mechanism. This invention prevents energy damage to the load due to misoperation during focused ultrasound use, and releases ultrasonic energy safely without causing unnecessary damage due to excessive energy release. Furthermore, different thresholds can be set based on different impedance conditions to meet varying energy requirements.

[0027] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method for controlling focused ultrasound energy output.

[0028] The present invention also provides a computer-readable storage medium having a computer program stored thereon, characterized in that, when the computer program is executed by a processor, it implements the steps of the method for controlling focused ultrasound energy output. Attached Figure Description

[0029] Figure 1 This is a timing diagram of detection and energy release in this invention.

[0030] Figure 2 This is a circuit diagram of the impedance detection circuit in this invention. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0032] Example 1

[0033] This embodiment provides a method for controlling the output of focused ultrasound energy. The ultrasound energy is output through electrodes and applied to a load (skin tissue).

[0034] First, the resistance of the load between the two electrodes needs to be calculated. This step also allows us to determine whether the electrodes are in contact with the load by calculating the resistance. Specifically, if the resistance between the two electrodes is infinite, it means there is an open circuit between them, and they are not in contact with the load. In this case, ultrasonic energy should not be emitted.

[0035] Specifically, the timing of detection and energy release is as follows: Figure 1 An impedance detection signal is emitted for a detection time of T1, while the focused ultrasound signal is emitted for T2. When the resistance value of the detection load meets the requirements, the focused ultrasound releases ultrasound energy. At this time, the impedance detection signal will always exist, and T1 is much smaller than T2. ​​The load resistance value can be calculated by collecting data between each treatment session T2. ​​At the same time, a resistance threshold is set. Focused ultrasound energy is only allowed to be emitted to the electrodes when the resistance value of the load is less than the resistance threshold.

[0036] In practical applications, more than two electrodes need to contact the skin tissue. In this case, it's necessary to detect the load resistance between adjacent electrodes and compare it to a resistance threshold. Focused ultrasound energy is only allowed to be emitted to each electrode when the load resistance between all adjacent electrodes is less than the resistance threshold. For example, four electrodes (A, B, C, and D) are set up as an electrode group to contact the skin tissue, and the resistance threshold is set to 500 ohms. The load resistance R between electrodes A and B... A-B The load resistance R between electrodes B and C B-C The load resistance R between electrodes C and D C-D The load resistance R between electrode D and electrode A D-A When all impedances are less than 500 ohms, focused ultrasound energy can be emitted. This method ensures that all electrodes are in contact with the load and that the impedance meets the requirements before energy can be output.

[0037] Then, consider the load resistance R between electrodes A and B. A-B Taking the calculation of R as an example, A-B =V0 / I0, and calculate the voltage V0 across the load and the current I0 flowing through the load using the following formula.

[0038] I0 = N1 * I1, V0 = N2 * V1;

[0039] Specifically, the voltage value V across the secondary side of the current transformer is collected by connecting the electrodes in series with the current transformer. Simple_A With V Simple_B The current I1 flowing through the secondary side of the current transformer; V1 = (V Simple_A +V Simple_B N1 is the turns ratio of the primary and secondary sides of the current transformer, and N2 is the turns ratio of the primary and secondary sides of the voltage transformer.

[0040] Example 2

[0041] This embodiment provides a system for controlling the energy output of focused ultrasound, including at least two electrodes, a host computer, and an ultrasound transducer.

[0042] The host computer is used to obtain the resistance value of the load between the two electrodes and set the resistance threshold. The ultrasonic transducer is used to emit focused ultrasonic energy; when the resistance value of the load is less than the resistance threshold, the host computer allows the ultrasonic transducer to emit focused ultrasonic energy to the electrodes.

[0043] After connecting a load between the two electrodes, the host computer calculates the voltage across the load and the current flowing through it, and then calculates the load's resistance based on these parameters. Specifically, the host computer includes an impedance detection circuit. Figure 2 As shown, the impedance detection circuit includes: a voltage transformer, a current transformer, a first sampling resistor (resistors R3 and R4 connected in series) connected in series with one end of the current transformer, a second sampling resistor (resistors R5 and R6 connected in series) connected in series with one end of the current transformer, a third sampling resistor (resistors R1 and R2 connected in series) connected in parallel with the secondary side of the current transformer, an AD sampling chip (not shown), and an impedance matching circuit. The AD sampling chip acquires the voltage value V across the secondary side of the current transformer. Simple_A With V Simple_B Through voltage value V Simple_A With V Simple_B The current I1 flowing through the secondary side of the current transformer is calculated by comparing it with the resistance values ​​of the first, second, and third sampling resistors respectively.

[0044] The voltage V0 across the load and the current I0 flowing through the load are calculated using the following formula.

[0045] I0 = N1 * I1, V0 = N2 * V1;

[0046] Where, V1=(V Simple_A +V Simple_BN1 is the turns ratio of the primary and secondary sides of the current transformer, and N2 is the turns ratio of the primary and secondary sides of the voltage transformer. In this embodiment, the primary side of the voltage transformer is the high-voltage side connected to V0, and the secondary side is the load side connected to V1. The voltage transformer is a sensor used to monitor AC voltage, and it converts high voltage to low voltage proportionally through the principle of electromagnetic induction.

[0047] The load resistance R between the two electrodes A-B =V0 / I0.

[0048] exist Figure 2 In the impedance detection circuit shown, a square wave is generated at L1 by controlling the closing sequence of S1, S2, S3, and S4. S1, S2, S3, and S4 must be controlled in such a way that S1 and S3 close simultaneously, and S2 and S4 close simultaneously. After passing through the impedance matching circuit, the square wave becomes a sine wave. When electrode A and electrode B are not in contact with skin tissue, there is an open circuit between them, and the current flowing through the current transformer is 0. When A and B are in contact with skin tissue, the current on the primary side is I0, and the current on the secondary side is I1, where I0 = N1 * I1 and V0 = N2 * V1. The relationship between the resistors in the circuit can be adjusted as needed. In this embodiment, R1 = R2 = R3 = R4 = R5 = R6 = R; V Simple_A With V Simple_B It can be acquired through an AD sampling chip, therefore I2=V Simple_A / 2R;I3=V Simple_B / 2R;I4=(V Simple_A -V1) / R=(V1-V Simple_B ) / R; therefore 2V1=V Simple_A +V Simple_B I1 = I2 + I3 + I4; I1 = (4V) Simple_A +V Simple_B -2V1) / 2R=3V simple_A / 2R.

[0049] Therefore, in the above sampling circuit, due to the time delay in the devices and lines, using time-division multiplexing sampling would result in inaccurate values. This circuit uses a superposition method of current and voltage, acquired by an ADC. The acquired value is obtained by adding the voltage and current, and the voltage and current values ​​on the primary side are calculated in reverse. Finally, R is obtained. A-B=V0 / I0. The real-time impedance between other electrodes is calculated similarly. This method allows the acquisition of the impedance of the treatment area. Since focused ultrasound generates heat when applied to the body, the impedance decreases. Given the significant differences in pain tolerance among patients, after acquiring the baseline impedance value, the acquisition of the lower impedance limit can be initiated simultaneously. Energy is then distributed within this impedance acquisition area, and the preset impedance threshold is adjusted based on patient feedback.

[0050] Furthermore, there are many specific methods and approaches to implement this invention, and the above description is only a preferred embodiment of this invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principle of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention.

Claims

1. A method for controlling the energy output of focused ultrasound, characterized in that: Calculate the resistance of the load between the two electrodes; Set a resistance threshold; when the resistance of the load is less than the resistance threshold, focused ultrasound energy is allowed to be emitted to the electrodes.

2. The method for controlling focused ultrasound energy output as described in claim 1, characterized in that, When multiple electrodes are provided, with loads between each adjacent electrode, and the resistance values ​​of all loads are less than the resistance threshold, focused ultrasound energy is allowed to be emitted to each electrode.

3. The method for controlling focused ultrasound energy output as described in claim 1 or 2, characterized in that, After connecting the load between the two electrodes, calculate the voltage across the load and the current flowing through the load, and then calculate the resistance of the load using the voltage and current.

4. The method for controlling focused ultrasound energy output as described in claim 3, characterized in that, Electrodes are connected in series with a current transformer to collect the voltage value V across the secondary side of the current transformer. Simple_A With V Simple_B The current I1 flowing through the two ends of the secondary side of the current transformer; The voltage V0 across the load and the current I0 flowing through the load are calculated using the following formula. I0 = N1 * I1, V0 = N2 * V1; Where, V1=(V Simple_A +V Simple_B N1 is the turns ratio of the primary and secondary sides of the current transformer, and N2 is the turns ratio of the primary and secondary sides of the voltage transformer. The load resistance R between the two electrodes A-B =V0 / I0.

5. A system for controlling the energy output of focused ultrasound, characterized in that, include: At least two electrodes, The host computer is used to obtain the resistance value of the load between the two electrodes and to set the resistance threshold. An ultrasonic transducer is used to emit focused ultrasonic energy; when the resistance of the load is less than the resistance threshold, the host computer allows the ultrasonic transducer to emit focused ultrasonic energy to the electrodes.

6. The system for controlling focused ultrasound energy output as described in claim 5, characterized in that, An ultrasonic transducer is connected to multiple electrodes. There is a load between each pair of adjacent electrodes, and the resistance value of all loads is less than the resistance threshold. When this condition is met, the host computer allows the ultrasonic transducer to emit focused ultrasonic energy to each electrode.

7. The system for controlling focused ultrasound energy output as described in claim 5 or 6, characterized in that, After the load is connected between the two electrodes, the host computer calculates the voltage across the load and the current flowing through the load, and then calculates the resistance value of the load based on the voltage and current.

8. The system for controlling focused ultrasound energy output as described in claim 7, characterized in that, It also includes an impedance detection circuit, which comprises: a voltage transformer, a current transformer, a first sampling resistor connected in series with one end of the current transformer, a second sampling resistor connected in series with one end of the current transformer, a third sampling resistor connected in parallel with the secondary side of the current transformer, and an AD sampling chip. The AD sampling chip acquires the voltage value V across the secondary side of the current transformer. Simple_A With V Simple_B Through voltage value V Simple_A With V Simple_B The current I1 flowing through the secondary side of the current transformer is calculated by comparing it with the resistance values ​​of the first, second, and third sampling resistors, respectively. The voltage V0 across the load and the current I0 flowing through the load are calculated using the following formula. I0 = N1 * I1, V0 = N2 * V1; Where, V1=(V Simple_A +V Simple_B N1 is the turns ratio of the primary and secondary sides of the current transformer, and N2 is the turns ratio of the primary and secondary sides of the voltage transformer. The load resistance R between the two electrodes A-B =V0 / I0.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 4.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 4.

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