Microwave ablation needle water circulation cooling system and method based on temperature feedback

Abstract

The invention discloses a microwave ablation needle water circulation cooling system and method based on temperature feedback, and belongs to the technical field of medical equipment.The microwave ablation needle water circulation cooling system comprises a temperature detection module installed on an ablation needle and used for collecting temperature information of the ablation needle in real time and transmitting the temperature information to a main control unit; the main control unit is used for dynamically adjusting the rotating speed of the coolant pump and the opening degree of the flow control valve by adopting a PID (Proportion Integration Differentiation) control algorithm; the cooling liquid circulating module is used for pumping cooling liquid into a cooling channel of the ablation needle according to an instruction of the main control unit and dynamically adjusting the temperature of the ablation needle; and the display unit is used for providing a real-time temperature display function, an alarm function and a parameter setting interface. Through real-time temperature detection and automatic control of the flowing speed of the pumped cooling liquid, it is ensured that the temperature of the ablation needle is stabilized within a safe range, and the safety and effectiveness of tumor microwave ablation treatment are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of medical devices, and particularly relates to a water circulation cooling system and method for a microwave ablation needle based on temperature feedback. Background Art

[0002] In tumor microwave ablation therapy, the microwave ablation needle generates heat through high-frequency electromagnetic waves to cause the tumor tissue to coagulate and necrosis. However, the ablation needle working at high temperatures may cause damage to the surrounding healthy tissues or the device. In the prior art, a water circulation cooling system is usually adopted to reduce the temperature of the ablation needle, but there is a lack of precise temperature feedback and automatic control mechanism, resulting in unstable cooling effect. Summary of the Invention

[0003] The purpose of the present invention is to address the above deficiencies in the prior art and provide a water circulation cooling system and method for a microwave ablation needle based on temperature feedback, so as to solve the problem of unstable cooling effect when the prior art uses a water circulation cooling system to reduce the temperature of the ablation needle.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is:

[0005] In a first aspect, a water circulation cooling system for a microwave ablation needle based on temperature feedback includes:

[0006] A temperature detection module, installed on the ablation needle, for real-time collecting the temperature information of the ablation needle and transmitting the temperature information to the main control unit;

[0007] The main control unit, adopting a PID control algorithm, dynamically adjusts the rotation speed of the coolant pump and the opening degree of the flow control valve;

[0008] A coolant circulation module, for pumping the coolant into the cooling channel of the ablation needle according to the instruction of the main control unit to dynamically adjust the temperature of the ablation needle;

[0009] A display unit, for providing a real-time temperature display, an alarm function, and a parameter setting interface.

[0010] Further, the temperature detection module includes a plurality of temperature sensors, and the plurality of temperature sensors are respectively arranged inside and on the surface of the ablation needle.

[0011] Further, the coolant circulation module includes a coolant storage tank, a coolant pump, a flow control valve, and a cooling pipeline; the coolant pump is connected to the coolant storage tank through a pipeline, and the flow control valve is arranged on the pipeline; the coolant pump pumps the coolant from the coolant storage tank into the cooling pipeline of the ablation needle.

[0012] Second aspect, a cooling method for a water circulation cooling system of a microwave ablation needle based on temperature feedback, comprising the following steps:

[0013] S1. Initialize the water circulation cooling system;

[0014] S2. The temperature detection module collects the temperature information of the ablation needle in real time and transmits the temperature information to the main control unit;

[0015] S3. The main control unit compares the received temperature information with the safe temperature threshold. If the temperature information is less than or equal to the safe temperature threshold, return to S2; if the temperature information is greater than the safe temperature threshold, execute S4;

[0016] S4. The control unit uses the PID algorithm to dynamically control the operation of the coolant circulation module and pump the coolant into the cooling pipeline of the ablation needle;

[0017] S5. The temperature detection module continues to collect the temperature information of the ablation needle and transmits the temperature information to the main control unit, and the main control unit dynamically adjusts the coolant flow rate according to the temperature information;

[0018] S6. The main control unit receives the temperature information of the ablation needle in real time. If the temperature information exceeds the safety upper limit, over-temperature protection is performed.

[0019] Further, in S3, the safe temperature threshold is 40 °C; if the temperature information of the ablation needle is less than or equal to the safe temperature threshold, control the coolant perfusion to maintain 80 revolutions per minute.

[0020] Further, in S4, the control unit uses the PID algorithm, which specifically includes the following sub-steps:

[0021] S41. Initialize the PID parameters, including the proportional parameter K p ., the integral parameter K i ., the derivative parameter K d ., the constant C and the safe temperature threshold Tset;

[0022] S42. Read the current actual temperature T of the ablation needle actual ;

[0023] S43. Calculate the error between the current actual temperature T of the ablation needle actual and the safe temperature threshold Tset:

[0024] e(t) = T actual - T set

[0025] In the formula, e(t) is the temperature error;

[0026] S44. Calculate the PID output u(t):

[0027] Proportional term P: P = Kp·e(t).

[0028] Integral term I: I = Ki·∑e(t).

[0029] Derivative term D: D = Kd·(e(t) - e(t - 1)).

[0030] u(t) = P + I + D + C

[0031] Wherein, the output u(t) corresponds to the pump power of the coolant pump from 0% to 100%;

[0032] S45. The main control unit controls the pump power of the coolant pump according to the output u(t) calculated in S44, and then adjusts the coolant flow rate;

[0033] S46. Save the current temperature error e(t);

[0034] S47. Return to step S2.

[0035] Furthermore, in S5, the main control unit dynamically adjusts the coolant flow rate according to the temperature information, including:

[0036] If the temperature information drops to the safe range, control the coolant pump to reduce the coolant flow rate;

[0037] If the temperature information continues to rise, control the coolant pump to increase the coolant flow rate.

[0038] Furthermore, in S6, the over-temperature protection includes:

[0039] Stop the microwave energy output of the ablation needle; and the main control unit controls the coolant pump to perfusion the coolant at the maximum power until the temperature drops to the safe range.

[0040] The microwave ablation needle water circulation cooling system and method based on temperature feedback provided by the present invention have the following beneficial effects:

[0041] 1. By real-time temperature detection and automatic control of the pumped coolant flow rate, the present invention ensures that the temperature of the ablation needle is stable within the safe range, improving the safety and effectiveness of tumor microwave ablation treatment.

[0042] 2. Precise temperature control: By real-time temperature feedback and PID control, ensure that the temperature of the ablation needle is stable within the safe range.

[0043] 3. Automatic operation: Reduce manual intervention and improve treatment safety and efficiency.

[0044] 4. Modular design: Easy to integrate into existing microwave ablation equipment.

[0045] 5. High safety: It has multiple protection mechanisms (such as temperature alarm, fault shutdown). Description of the Drawings

[0046] Figure 1 It is a system block diagram of the microwave ablation needle water circulation cooling system based on temperature feedback in Embodiment 1 of the present invention.

[0047] Figure 2 It is a flowchart of the cooling method of the microwave ablation needle water circulation cooling system based on temperature feedback in Embodiment 2 of the present invention.

[0048] Figure 3 It is a flowchart of the PID algorithm in Embodiment 2 of the present invention. Detailed Embodiments

[0049] The following describes the detailed embodiments of the present invention to facilitate those skilled in the art of the present technology to understand the present invention. However, it should be clear that the present invention is not limited to the scope of the detailed embodiments. For those of ordinary skill in the art of the present technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions created using the concept of the present invention are within the scope of protection.

[0050] Embodiment 1

[0051] This embodiment provides a microwave ablation needle water circulation cooling system based on temperature feedback. By real-time temperature detection and automatic control of the flow rate of the pumped coolant, it ensures that the temperature of the ablation needle is stable within a safe range. Refer to Figure 1 , and it specifically includes:

[0052] A temperature detection module, installed on the ablation needle, for real-time collecting the temperature information of the ablation needle and transmitting the temperature information to the main control unit;

[0053] Specifically, the temperature detection module of this embodiment includes multiple temperature sensors, and the multiple temperature sensors are respectively arranged inside and on the surface of the ablation needle;

[0054] As a preference of this embodiment, the temperature sensor is selected from a thermocouple or a thermistor, and the thermocouple or the thermistor is connected to the main control unit through a signal line.

[0055] The main control unit receives the data of the temperature sensor, conducts real-time analysis and processing, and adopts the PID control algorithm according to the preset safe temperature threshold to dynamically adjust the rotation speed of the coolant pump and the opening degree of the flow control valve.

[0056] The coolant circulation module is used to pump the coolant into the cooling channel of the ablation needle according to the instruction of the main control unit to dynamically adjust the temperature of the ablation needle;

[0057] Specifically, it includes a coolant storage tank, a coolant pump, a flow control valve, and a cooling pipeline. The coolant pump is connected to the coolant storage tank through a pipeline, and a flow control valve is provided on this pipeline; the coolant pump pumps the coolant from the coolant storage tank into the cooling pipeline of the ablation needle.

[0058] A display unit, which is used to provide real-time temperature display, alarm function, and parameter setting interface. Users can set the target temperature range and coolant flow rate on the display unit.

[0059] The hardware implementation of this embodiment is as follows:

[0060] Temperature sensor: A high-precision thermocouple is adopted and installed at key positions of the ablation needle, such as in the coolant return chamber at the tip or handle of the ablation needle.

[0061] Main control unit: Implemented based on a microcontroller (such as the ARM Cortex-M series).

[0062] Coolant pump: An integrated micro peristaltic pump with adjustable flow rate.

[0063] Software implementation:

[0064] Temperature data acquisition: Read the temperature sensor data through the ADC module.

[0065] PID control algorithm: Implemented in the main control unit to calculate the coolant flow rate in real time.

[0066] Display unit: Set parameters through a touch screen or buttons, and display real-time temperature and historical data.

[0067] The working principle of this embodiment is as follows:

[0068] The temperature sensor monitors the temperature of the ablation needle in real time and transmits the collected temperature information data to the main control unit. The main control unit compares the temperature information data with the safety temperature threshold: if the temperature exceeds the safety temperature threshold, the coolant flow rate is increased; if the temperature is lower than the lower limit, the coolant flow rate is decreased. And the PID control algorithm is used to dynamically adjust the rotation speed of the coolant pump and the opening degree of the flow control valve. That is, the coolant pump pumps the coolant into the cooling pipeline of the ablation needle according to the instructions of the main control unit. If the temperature exceeds the safety range or the system fails, the main control unit triggers an audible and visual alarm and automatically stops the operation of the microwave ablation device.

[0069] Embodiment 2

[0070] This embodiment provides a cooling method for a microwave ablation needle water circulation cooling system based on temperature feedback. Refer to Figure 2 , which specifically includes the following steps:

[0071] S1. Initialize the water circulation cooling system;

[0072] S2. The temperature detection module collects the temperature information of the ablation needle in real time and transmits the temperature information to the main control unit;

[0073] S3. The main control unit compares the received temperature information with the safe temperature threshold. If the temperature information is less than or equal to the safe temperature threshold, it returns to S2; if the temperature information is greater than the safe temperature threshold, it executes S4;

[0074] In this embodiment, the safe temperature threshold is set to 40 °C; if the temperature information of the ablation needle is less than or equal to the safe temperature threshold, the coolant perfusion is controlled to maintain 80 revolutions per minute.

[0075] S4. The control unit uses the PID algorithm to dynamically control the operation of the coolant circulation module and pumps the coolant into the cooling pipeline of the ablation needle;

[0076] In this embodiment, the control unit uses the PID algorithm with reference to Figure 3 , which specifically includes the following sub-steps:

[0077] S41. Initialize the PID parameters, including the proportional parameter Kp, the integral parameter Ki, the derivative parameter Kd, the constant C, and the safe temperature threshold Tset. The safe temperature threshold Tset is preferably 40 °C.

[0078] S42. Read the current actual temperature T of the ablation needle actual ;

[0079] S43. Calculate the error between the current actual temperature T of the ablation needle actual and the safe temperature threshold Tset:

[0080] e(t) = T actual - T set

[0081] In the formula, e(t) is the temperature error;

[0082] S44. Calculate the PID output u(t):

[0083] Proportional term P: P = Kp·e(t).

[0084] Integral term I: I = Ki·∑e(t).

[0085] Derivative term D: D = Kd·(e(t) - e(t - 1)).

[0086] u(t) = P + I + D + C

[0087] In the formula, the output u(t) corresponds to the pump power of the coolant pump from 0% to 100%;

[0088] Proportional term (P): Responds quickly to temperature changes, but an excessive Kp may cause system oscillations.

[0089] Integral term (I): Eliminates steady-state error, but an excessive Ki may cause slow system response.

[0090] Derivative term (D): Suppresses temperature fluctuations, but an excessive Kd may amplify noise

[0091] S45. The main control unit, based on the output u(t) calculated in S44, restricts the output u(t) within a reasonable range (such as 0% - 100%); controls the pump power of the coolant pump, and thereby adjusts the coolant flow rate;

[0092] In this embodiment, according to the change of the error e(t), when the error e(t) is within 0 - 5°C, the corresponding u(t) is output to control the power of the coolant pump. For every 1°C increase in the error, the corresponding increment of u(t) is output to increase the power of the coolant pump.

[0093] In the PID control of this embodiment, when the temperature approaches the set value, the role of the derivative term is enhanced to avoid temperature overshoot. When the temperature deviates from the set value, the proportional term and the integral term act together to quickly adjust the coolant flow rate.

[0094] S46. Save the current temperature error e(t);

[0095] S47. Return to step S2.

[0096] S5. The temperature detection module continues to collect the temperature information of the ablation needle and transmits this temperature information to the main control unit, and the main control unit dynamically adjusts the coolant flow rate according to this temperature information;

[0097] The main control unit of this embodiment dynamically adjusts the coolant flow rate according to this temperature information, including:

[0098] If the temperature information drops to the safe range, control the coolant pump to reduce the coolant flow rate;

[0099] If the temperature information continues to rise, control the coolant pump to increase the coolant flow rate.

[0100] S6. The main control unit receives the temperature information of the ablation needle in real time. If the temperature information exceeds the safety upper limit, over-temperature protection is performed.

[0101] The over-temperature protection includes:

[0102] Stop the microwave energy output of the ablation needle; and the main control unit controls the coolant pump to perfusion the coolant at the maximum power until the temperature drops to the safe range.

[0103] This embodiment further includes:

[0104] Fault detection;

[0105] The system detects the working status of the temperature sensor and the coolant circulation system in real time. If a fault is detected, an alarm is triggered and the system operation is stopped.

[0106] Finally, the treatment is completed and the system stops running.

[0107] Although the specific embodiments of the invention have been described in detail with reference to the accompanying drawings, it should not be construed as a limitation on the protection scope of this patent. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative efforts still fall within the protection scope of this patent.

Claims

1. A microwave ablation needle water circulation cooling system based on temperature feedback, characterized in that: include: The temperature detection module is installed on the ablation needle and is used to collect the temperature information of the ablation needle in real time and transmit the temperature information to the main control unit; The main control unit uses PID control algorithm to dynamically adjust the speed of the coolant pump and the opening of the flow control valve; A coolant circulation module is used to pump coolant into the cooling channel of the ablation needle according to the instructions of the main control unit to dynamically adjust the temperature of the ablation needle; The display unit is used to provide real-time temperature display, alarm function and parameter setting interface.

2. The microwave ablation needle water circulation cooling system based on temperature feedback according to claim 1 is characterized in that: The temperature detection module includes a plurality of temperature sensors, and the plurality of temperature sensors are respectively arranged inside and on the surface of the ablation needle.

3. The microwave ablation needle water circulation cooling system based on temperature feedback according to claim 1 is characterized in that: The coolant circulation module includes a coolant storage tank, a coolant pump, a flow control valve and a cooling pipeline; the coolant pump is connected to the coolant storage tank through a pipeline, and the flow control valve is arranged on the pipeline; the coolant pump pumps the coolant from the coolant storage tank to the cooling pipeline of the ablation needle.

4. A cooling method for a microwave ablation needle water circulation cooling system based on temperature feedback according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, water circulation cooling system initialization; S2, the temperature detection module collects the temperature information of the ablation needle in real time and transmits the temperature information to the main control unit; S3, the main control unit compares the received temperature information with the safety temperature threshold. If the temperature information is less than or equal to the safety temperature threshold, it returns to S2; if the temperature information is greater than the safety temperature threshold, it executes S4; S4, the control unit uses a PID algorithm to dynamically control the operation of the coolant circulation module to pump the coolant into the cooling pipeline of the ablation needle; S5, the temperature detection module continues to collect the temperature information of the ablation needle, and transmits the temperature information to the main control unit, and the main control unit dynamically adjusts the flow rate of the coolant according to the temperature information; S6. The main control unit receives the temperature information of the ablation needle in real time. If the temperature information exceeds the safety upper limit, over-temperature protection is performed.

5. The cooling method of the microwave ablation needle water circulation cooling system based on temperature feedback according to claim 4, characterized in that: In S3, the safety temperature threshold is 40°C; if the temperature information of the ablation needle is less than or equal to the safety temperature threshold, the cooling liquid perfusion is controlled to maintain 80 revolutions per minute.

6. The cooling method of the microwave ablation needle water circulation cooling system based on temperature feedback according to claim 4, characterized in that: In S4, the control unit adopts a PID algorithm, which specifically includes the following sub-steps: S41, initialize PID parameters, including proportional parameter K p , integration parameter K i , differential parameter K d , constant C and safety temperature threshold Tset; S42, read the current actual ablation needle temperature T actual ; S43, calculating the current actual ablation needle temperature T actual The error between the safety temperature threshold Tset: e(t)=T actual -T set Where, e(t) is the temperature error; S44, calculate PID output u(t): Proportional term P: P = Kp·e(t). Integral term I: I = Ki·∑e(t). Differential term D: D = Kd·(e(t)-e(t-1)). u(t)=P+I+D+C Wherein, the output u(t) corresponds to 0% to 100% of the pump power of the coolant pump; S45, the main control unit controls the pump power of the coolant pump according to the output u(t) calculated in S44, thereby adjusting the coolant flow rate; S46, saving the current temperature error e(t); S47. Return to step S2.

7. The cooling method of the microwave ablation needle water circulation cooling system based on temperature feedback according to claim 4, characterized in that: In S5, the main control unit dynamically adjusts the coolant flow rate according to the temperature information, including: If the temperature information drops to within a safe range, the coolant pump is controlled to reduce the coolant flow rate; If the temperature information continues to rise, the coolant pump is controlled to increase the coolant flow rate.

8. The cooling method of the microwave ablation needle water circulation cooling system based on temperature feedback according to claim 4, characterized in that: In S6, the over-temperature protection includes: The microwave energy output of the ablation needle is stopped; and the main control unit controls the coolant pump to inject coolant at maximum power until the temperature drops to a safe range.

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