CN115990057A

CN115990057A - Power control method and system for varicose vein radio frequency ablation catheter

Info

Publication number: CN115990057A
Application number: CN202310283564.XA
Authority: CN
Inventors: 陈强; 王志青; 张城照; 张婵娟
Original assignee: Zhejiang Curaway Medical Technology Co ltd
Current assignee: Zhejiang Curaway Medical Technology Co ltd
Priority date: 2023-03-22
Filing date: 2023-03-22
Publication date: 2023-04-21
Anticipated expiration: 2043-03-22
Also published as: CN115990057B

Abstract

The invention discloses a power control method, a system, a power control method and a power control device for radio frequency ablation of varicose vein, wherein in the starting process of a radio frequency generator, a main control module reads preset calibration data form information into a system memory, current information on a heating unit is collected, current impedance coefficient information is calculated based on the collected information, the calibration data form is queried according to the current impedance coefficient information, and then the current impedance value information and the current voltage coefficient information are calculated through a linear method; and then calculating to obtain current effective power information based on the acquired electric information, the current voltage coefficient information and the current impedance value information, and adjusting and controlling the current effective power information to preset target power information according to the current effective power information, so that the heating unit quickly reaches the set power and is kept so as to continuously heat the vein wall to shrink the vein wall collagen.

Description

Power control method and system for varicose vein radio frequency ablation catheter

Technical Field

The invention relates to the field of radio frequency ablation, in particular to a power control method and system of a varicose vein radio frequency ablation catheter, a power control method and device for radio frequency ablation and computer equipment.

Background

Varicose veins are a common medical condition affecting up to 60% and represent a significant health and beauty problem. Symptomatically, dilated varicose veins (usually the great saphenous vein) can cause pain, cramps, itching, swelling, skin changes, venous stasis ulcers and pain. The traditional therapy for treating varicose veins is surgical excision (vein stripping), but less invasive treatments are now becoming more common. Sclerotic treatments (injection of caustic substances to scar veins), laser and radio frequency closure techniques, and minimally invasive surgery, are becoming increasingly popular. Energy transfer processes (laser, radio frequency, etc.) hold promise due to their relatively low technical difficulty and good accuracy.

For the radiofrequency ablation means, an electric heating wire is arranged in an ablation catheter, then radiofrequency current is applied to the electric heating wire to heat the electric heating wire, further the curved vein wall is heated, collagen acting on the vein wall is contracted, and finally the purpose of closing is achieved. However, precise and stable control of the output of the radio frequency control signal has been a challenge. First, the detection of power is performed by detecting the voltage effective value and the current effective value of the high-frequency ac signal. However, since the high-frequency voltage transformer and the high-frequency current transformer have nonlinear problems, the effective voltage value and the effective current value do not linearly reflect the voltage level and the current level of the high-frequency alternating current signal, and the voltage current detection point and the heating unit are connected through a long cable, attenuation and loss of the high-frequency alternating current signal can be caused, the power value of the detection point is not completely the power value on the heating unit, the current power value of the heating unit which is not the most accurate currently acquired power value exists, and delay exists. Secondly, based on delayed power detection, inaccuracy and instability in power control are further caused, namely, the current power change needs to be quickly responded and then quickly adjusted, the current change of the power cannot be quickly adjusted, and therefore, the change acts on vein wall collagen, and a good ablation effect cannot be achieved.

In addition, other radio frequency ablation applications also have the technical problem that the power control method is not accurate.

Disclosure of Invention

The invention aims to provide a power control method and system for a varicose vein radiofrequency ablation catheter, and a power control method, device, computer equipment and storage medium for radiofrequency ablation, which can enable the radiofrequency vein ablation catheter to quickly reach target ablation power in a short time, continuously maintain the target ablation power, and have the advantages of quick response time and high precision.

Based on the above objects, one technical scheme of the present invention is as follows: a method of power control of a varicose radiofrequency ablation catheter, comprising the steps of: in the starting process of the radio frequency generator, the main control module reads preset calibration data form information into a system memory; the radio frequency generator is used for supplying high-frequency current to the heating unit in the catheter, and the current output current information and output voltage information on the heating unit are collected through the collecting unit; calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method; acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling to preset target power information according to the current effective power information, so that the heating unit can quickly reach set power and maintain the set power, and continuously heating the vein wall to shrink the vein wall collagen.

Preferably, before the preset calibration data table information is read into the system memory, the method further comprises: adjusting the impedance of an electronic load of the heating unit of the simulated ablation catheter to a target test impedance value and a target test voltage value preset when the system is adjusted to the target test impedance value; acquiring test voltage value data and test current value data of the heating unit when the target test impedance value and the target test voltage value are obtained; calculating impedance coefficient data and voltage coefficient data under a target test impedance value based on the test voltage value data and the test current value data; storing the target test impedance value, impedance coefficient data and voltage coefficient data under the target test impedance value into the calibration data table; and adjusting the impedance of the electronic load and the voltage value of the system when the impedance value is tested according to a preset step length so as to realize the test and recording of the data in the calibration data table.

Preferably, the method further comprises: adjusting the impedance value of the electronic load according to a preset fixed step length; or, adjusting the impedance value of the electronic load according to the step length which satisfies the change of a preset functional relation; and ending the test to finish the calibration data table under the condition that the impedance value of the electronic load is larger than a preset threshold value.

Preferably, the step of searching the calibration data table according to the current impedance coefficient information, and then calculating the current impedance value information and the current voltage coefficient information by a linear method further includes: querying the calibration data table information based on current impedance coefficient information to determine an impedance coefficient range and a corresponding voltage coefficient range; and calculating a current impedance value and a current voltage coefficient by a linear method based on the current impedance coefficient information, the determined impedance coefficient range and the corresponding voltage coefficient range.

Preferably, the method for applying a high-frequency current to the heat generating unit in the catheter by the radio frequency generator further comprises: the main control module inputs a high-frequency pulse signal to a high-frequency switch signal circuit in a power DC-AC module of the radio frequency generator so as to control a half-bridge circuit in the power DC-AC module to convert direct-current voltage into square waves; converting the square wave into a high-frequency alternating voltage through a frequency selecting circuit in the half-bridge circuit; the main control module sweeps in a preset frequency range under rated load to detect output power of all frequencies in the frequency range, and the frequency when the output power is maximum is determined to be the frequency of the high-frequency pulse signal of the system.

Preferably, the radio frequency generator supplies a high frequency current to the heating unit in the catheter further comprises: the power DC-DC module in the radio frequency generator generates an analog signal to adjust the pulse width of a switching signal of the power DC-DC module so as to realize the adjustment of output voltage, wherein after the main control module writes the data of the power DC-DC module, the main control module reads the data from the power DC-DC module and compares the data with the written original data, and if the data are the same, the power DC-DC module outputs a corresponding analog signal.

Preferably, obtaining current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling to preset target power information according to the current effective power information further includes: calculating a present effective power of the heat generating unit based on effective power = effective voltage = effective current; and comparing the current effective power information with the target power information of the heating unit, and adjusting the resistance value of the heating unit of the ablation catheter and/or the output voltage value of the system according to a preset program under the condition that the comparison result exceeds a preset threshold value.

Based on the above object, another technical scheme of the present invention is as follows: the utility model provides a varicosity radio frequency ablation catheter's power control system, includes radiofrequency generator, collection unit, heating element, main control module, wherein: the radio frequency generator is used for supplying high-frequency current to the heating unit in the catheter; the acquisition unit is used for acquiring the current output current information and the current output voltage information on the heating unit; the main control module further comprises: the loading module is used for reading preset calibration data form information into the system memory in the starting process of the radio frequency generator; the acquisition module is used for leading the high-frequency current to the heating unit in the catheter by the radio-frequency generator and acquiring the current output current information and output voltage information on the heating unit by the acquisition unit; the calculation module is used for calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method; the control module is used for acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, adjusting and controlling the current effective power information to preset target power information according to the current effective power information, enabling the heating unit to quickly reach set power and maintain the set power, and continuously heating the vein wall to enable the vein wall collagen to shrink.

Preferably, the radio frequency generator further comprises: the main control module controls the power DC-DC module to generate an analog signal to adjust the switching signal pulse of the power DC-DC module, so that the purpose of adjusting output voltage is achieved, and the power DC-AC module is connected with the radio frequency ablation catheter through a catheter interface module.

Preferably, the power DC-AC module further comprises: the high-frequency switch signal circuit is used for generating a power switch tube signal for driving the DC-AC half-bridge circuit so as to convert the realized direct-current voltage into square waves, and then the square waves are converted into high-frequency alternating-current voltage through a frequency selection circuit in the DC-AC half-bridge circuit; in the system debugging stage, the main control module sweeps in a certain frequency range, detects output power of all frequencies in the frequency range, and determines the frequency with the maximum output power as the frequency of the final high-frequency pulse signal so as to realize the efficiency optimization of the system.

Preferably, after the main control module writes data into the power DC-DC module, the main control module reads the data from the power DC-DC module and compares the data with the written original data, and if the data are the same, the power DC-DC module outputs a corresponding analog signal.

Preferably, the system further comprises a temperature acquisition module for acquiring the temperature of the heating unit in the radio frequency ablation catheter and sending the temperature to the main control module.

Preferably, the system further comprises a touch screen module, wherein the touch screen module is in signal connection with the main control module and is used for receiving parameter settings of a user.

Preferably, the system further comprises a power supply module for supplying power to a module in the system that needs to be supplied with power.

Based on the above object, another technical scheme of the present invention is as follows: a power control method for radio frequency ablation, comprising the steps of: in the starting process of the radio frequency generator, the main control module reads preset calibration data form information into a system memory; the radio frequency generator is used for supplying high-frequency current to an ablation load, and collecting current output current information and output voltage information on the ablation load through the collecting unit; calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method; acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling the current effective power information to preset target power information according to the current effective power information, so that the ablation load quickly reaches set power and is maintained, and heating and ablation are continuously carried out on target tissues.

Preferably, before the preset calibration data table information is read into the system memory, the method further comprises: adjusting the impedance of an electronic load simulating an ablation load to a target test impedance value and a target test voltage value preset when the system is adjusted to the target test impedance value; acquiring test voltage value data and test current value data of an ablation load when the target test impedance value and the target test voltage value are obtained; calculating impedance coefficient data and voltage coefficient data under a target test impedance value based on the test voltage value data and the test current value data; storing the target test impedance value, impedance coefficient data and voltage coefficient data under the target test impedance value into the calibration data table; and adjusting the impedance of the electronic load and the voltage value of the system when the impedance value is tested according to a preset step length so as to realize the test and recording of the data in the calibration data table.

Preferably, the method of applying high frequency current to an ablation load by the radio frequency generator further comprises: the main control module inputs a high-frequency pulse signal to a high-frequency switch signal circuit in a power DC-AC module of the radio frequency generator so as to control a half-bridge circuit in the power DC-AC module to convert direct-current voltage into square waves; converting the square wave into a high-frequency alternating voltage through a frequency selecting circuit in the half-bridge circuit; the main control module sweeps in a preset frequency range under rated load to detect output power of all frequencies in the frequency range, and the frequency when the output power is maximum is determined to be the frequency of the high-frequency pulse signal of the system.

Preferably, the rf generator applies a high frequency current to the ablation load further comprising: the power DC-DC module in the radio frequency generator generates an analog signal to adjust the pulse width of a switching signal of the power DC-DC module so as to realize the adjustment of output voltage, wherein after the main control module writes the data of the power DC-DC module, the main control module reads the data from the power DC-DC module and compares the data with the written original data, and if the data are the same, the power DC-DC module outputs a corresponding analog signal.

Preferably, obtaining current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling to preset target power information according to the current effective power information further includes: calculating the current effective power of the ablation load based on the effective power = effective voltage; and comparing the current effective power information with target power information of an ablation load, and adjusting the resistance value of the ablation load and/or the output voltage value of the system according to a preset program under the condition that the comparison result exceeds a preset threshold value.

Based on the above object, another technical scheme of the present invention is as follows: a power control system for radio frequency ablation, comprising: the device comprises a radio frequency generator, an acquisition unit, an ablation load and a main control module, wherein: a radio frequency generator for applying a high frequency current to the ablation load; the acquisition unit is used for acquiring current output current information and output voltage information on the ablation load; the main control module further comprises: the loading module is used for reading preset calibration data form information into the system memory in the starting process of the radio frequency generator; the system comprises an acquisition module, a control module and a control module, wherein the acquisition module is used for leading high-frequency current to an ablation load by the radio frequency generator and acquiring current output current information and output voltage information on the ablation load by the acquisition unit; the calculation module is used for calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method; the control module is used for acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, the current voltage coefficient information and the current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, adjusting and controlling the current effective voltage information and the current effective current information to preset target power information according to the current effective power information, so that the ablation load quickly reaches and maintains the set power, and heating and ablation are continuously carried out on target tissues.

Preferably, the radio frequency generator further comprises: the main control module controls the power DC-DC module to generate an analog signal to adjust the switching signal pulse of the power DC-DC module, so that the aim of adjusting output voltage is fulfilled, and the power DC-AC module is connected with the ablation load through a load interface module.

Preferably, the system further comprises a temperature acquisition module for acquiring the temperature of the ablation load and sending the temperature to the main control module.

Based on the same inventive concept, the present invention provides a computer apparatus comprising: a memory for storing a processing program; and the processor is used for realizing the power control method of the varicose vein radio-frequency ablation catheter or the power control method for radio-frequency ablation when executing the processing program.

Based on the same inventive concept, the invention provides a readable storage medium, on which a processing program is stored, which when executed by a processor, implements the power control method of the varicose vein radio frequency ablation catheter or the power control method for radio frequency ablation.

By adopting the technical scheme, the invention has the following advantages and positive effects compared with the prior art:

1. the invention firstly reads a calibration data table which is subjected to experiments in advance into a system memory, then acquires the current output current and output voltage of the system, calculates the current impedance coefficient, looks up a table according to the calculated current impedance coefficient, calculates the current impedance value and the current voltage coefficient by using a linear method, and calculates the current effective voltage and the effective current to obtain effective power. Therefore, only when the system is started, the calibration data table which is finished in advance and stored in the system is read into the memory, the current effective power of the system can be obtained through table lookup and simple calculation of a plurality of steps after the current output current and the current output voltage are acquired, the efficiency of power acquisition is improved, positive feedback can be provided for the system rapidly, the system can achieve the preset target power rapidly, and the ablation efficiency is improved.

2. According to the invention, the impedance value in the calibration data table can be adjusted by adopting a fixed step length, and the calibration data table can be obtained in limited experimental data; according to the invention, the impedance value in the calibration data table adopts the step length of linear change or nonlinear change, the smaller step length is adopted in the region with obvious change, and the larger step length is adopted in the region with gentle change, so that detailed and reasonable experimental data can be provided, and the fitting precision is improved.

3. According to the invention, for each system, the fact that the dispersion of component parameters in the half-bridge circuit exists, so that the resonance frequencies of frequency selection circuits of different systems are inconsistent is considered, and a single high-frequency pulse signal can cause obvious increase of the thermal effect of part of circuits for different systems, so that the efficiency is reduced, the high-frequency switching noise is increased, and the work is unstable. The main control module of the invention sweeps in a preset frequency range to detect the output power of all frequencies in the frequency range, and determines the frequency when the output power is maximum as the frequency of the high-frequency pulse signal of the system. Therefore, the low thermal effect is finally realized, the efficiency is improved, the high-frequency switching noise is reduced, and the working stability is ensured.

4. According to the invention, the main control module writes the data into the power DC-DC module, reads out the data which are compared with the written data, and if the data are the same, allows the power DC-DC module to output corresponding analog signals, so that accurate and stable switch signal pulse width is generated, and the control precision is high.

5. According to the invention, the main control module adjusts the pulse width of the switching signal of the power DC-DC module by setting the power DC-DC module to generate the analog signal, so that the aim of adjusting the output voltage is fulfilled, high-frequency switching noise can be effectively avoided, and the anti-interference performance is improved.

Drawings

FIG. 1 is a schematic diagram of a prior art RF ablation system;

FIG. 2 is a schematic diagram of the functional blocks of the power control system of the varicose radiofrequency ablation catheter of the present invention;

FIG. 3 is an exemplary diagram of a current/voltage detection module;

FIG. 4 is a flowchart of a method for obtaining a calibration data table according to an embodiment;

FIG. 5 is a flow chart of a method of one embodiment of power control for a radio frequency ablation catheter;

FIG. 6 is a schematic diagram of a power DC-AC module;

fig. 7 is a schematic diagram of an embodiment of a power control system for a varicose radiofrequency ablation catheter.

Detailed Description

Other advantages and effects of the present invention will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present invention with reference to specific examples. The invention may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present invention. It is to be understood that the terms "center," "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are directional or positional relationships as indicated based on the drawings, merely to facilitate describing the invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus are not to be construed as limiting the invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first", "a second", etc. may explicitly or implicitly include one or more such feature. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more.

It should be noted that, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art in a specific case.

Example 1

Referring to fig. 1, the composition of a radio frequency ablation system as is common in the prior art is shown.

Referring to fig. 2, a schematic diagram of the functional modules of the power control system of the varicose radiofrequency ablation catheter of the present invention is shown. A power control system of a varicose vein radio frequency ablation catheter, see fig. 7, comprises a radio frequency generator, an acquisition unit, a heating unit and a main control module, wherein: the radio frequency generator is used for supplying high-frequency current to the heating unit in the catheter and specifically comprises a power DC-DC module and a power DC-AC module; the acquisition unit is used for acquiring current output current information and output voltage information on the heating unit, and specifically comprises a voltage detection module and a current detection module; the main control module further comprises: the loading module is used for reading preset calibration data form information into the system memory in the starting process of the radio frequency generator; the acquisition module is used for leading the high-frequency current to the heating unit in the catheter by the radio-frequency generator and acquiring the current output current information and output voltage information on the heating unit by the acquisition unit; the calculation module is used for calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method; the control module is used for acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, adjusting and controlling the current effective power information to preset target power information according to the current effective power information, enabling the heating unit to quickly reach set power and maintain the set power, and continuously heating the vein wall to enable the vein wall collagen to shrink.

The power control system of the varicose vein radio frequency ablation catheter of the embodiment firstly reads a calibration data table which is subjected to experiments in advance into a system memory, then acquires the current output current and output voltage of the system, calculates the current impedance coefficient, looks up a table according to the calculated current impedance coefficient, calculates the current impedance value and the current voltage coefficient by using a linear method, and then calculates the current effective voltage and effective current, thereby obtaining effective power. Therefore, only when the system is started, the calibration data table which is finished in advance and stored in the system is read into the memory, the current effective power of the system can be obtained through table lookup and simple calculation of a plurality of steps after the current output current and the current output voltage are acquired, the efficiency of power acquisition is improved, positive feedback can be provided for the system rapidly, the system can achieve the preset target power rapidly, and the ablation efficiency is improved.

Preferably, with continued reference to fig. 2, the radio frequency generator further comprises: the main control module controls the power DC-DC module to generate an analog signal to adjust the switching signal pulse of the power DC-DC module, so that the purpose of adjusting output voltage is achieved, and the power DC-AC module is connected with the radio frequency ablation catheter through a catheter interface module. The main function of the power DC-DC module is to realize the conversion from direct voltage to direct voltage, and the anti-interference design is critical because of the high-frequency switching noise existing in the environment of the embodiment. The main control module adjusts the pulse width of the switching signal of the power DC-DC module by setting the power DC-DC module to generate an analog signal, thereby achieving the purpose of adjusting the output voltage, effectively avoiding high-frequency switching noise and improving the anti-interference performance.

Preferably, referring to fig. 6, the power DC-AC module further includes: the high-frequency switch signal circuit is used for generating a power switch tube signal for driving the DC-AC half-bridge circuit so as to convert the realized direct-current voltage into square waves, and then the square waves are converted into high-frequency alternating-current voltage through a frequency selection circuit in the DC-AC half-bridge circuit; in the system debugging stage, the main control module sweeps in a certain frequency range, detects output power of all frequencies in the frequency range, and determines the frequency with the maximum output power as the frequency of the final high-frequency pulse signal so as to realize the efficiency optimization of the system.

The high-frequency switch signal circuit generates a signal for driving a power switch tube of the DC-AC half-bridge circuit, converts direct-current voltage into square waves, and converts the square waves into high-frequency alternating-current voltage through the frequency selection circuit. Because of the dispersion of component parameters of the DC-AC half-bridge circuit, the resonance frequency of the frequency selection circuit is inconsistent, if a high-frequency pulse signal is fixed, the thermal effect of the circuit is obviously increased, the efficiency is reduced, the high-frequency switching noise is increased, and the operation is unstable. In order to enable the high-frequency pulse signal finally output by the main control module to be matched with the resonance frequency of the frequency selection circuit, under rated load, the main control module sweeps in a certain frequency range, detects output power of all frequencies in the frequency range, and determines the frequency when the output power is maximum as the frequency of the final high-frequency pulse signal, so that the low-heat effect is finally realized, the efficiency is improved, the high-frequency switching noise is reduced, and the working stability is ensured.

Due to the high-frequency switching noise, the data written into the power DC-DC module is often wrong, so that the output voltage is wrong, the actual power output is affected, and the aims of accurate and stable control are not achieved. In order to achieve the purpose, the main control module writes the data into the power DC-DC module, reads out the data to be compared with the written data, and if the data are the same, allows the power DC-DC module to output corresponding analog signals, so that accurate and stable switch signal pulse width is generated, and the control precision is high.

Preferably, referring to fig. 2, the system further includes a touch screen module, which is in signal connection with the main control module and is used for receiving parameter settings of a user.

Through setting up the touch-sensitive screen module, can realize that the operator of this system sets up the relevant parameter of system to match different models, different kind's ablation pipe, improve the compatibility of system.

Referring to fig. 3, an exemplary diagram of a current/voltage detection module is shown, namely, signal acquisition is performed on the voltage and the current of the varicose radiofrequency ablation catheter heating unit through a voltage/current transformer. The detection of the power of the heating unit of the radio frequency ablation catheter is realized by detecting the effective voltage value and the effective current value of the high-frequency alternating current signal. Because the high-frequency voltage transformer and the high-frequency current transformer have nonlinear problems, the voltage effective value and the current effective value do not linearly reflect the voltage and the current of the high-frequency alternating current signal, and the voltage and current detection points are connected with the heating wire through a long cable, so that the attenuation and the loss of the high-frequency alternating current signal can be caused, and the power value of the detection point is not completely the power value on the heating unit. Accordingly, in order to solve the above problems, there is provided a power control method of a varicose radiofrequency ablation catheter, corresponding to the above power control system of a varicose radiofrequency ablation catheter, comprising the steps of:

s100: in the starting process of the radio frequency generator, the main control module reads preset calibration data form information into a system memory;

S200: the radio frequency generator is used for supplying high-frequency current to the heating unit in the catheter, and the current output current information and output voltage information on the heating unit are collected through the collecting unit;

s300: calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method;

s400, performing S400; acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling to preset target power information according to the current effective power information, so that the heating unit can quickly reach set power and maintain the set power, and continuously heating the vein wall to shrink the vein wall collagen.

Firstly, reading a calibration data table which is subjected to experiments in advance into a system memory, then collecting current output current information and output voltage information on a heating unit, calculating current impedance coefficient information, looking up a table according to the calculated current impedance coefficient information, calculating current impedance value information and current voltage coefficient information by using a linear method, and then calculating to obtain current effective voltage information and effective current information, thereby obtaining effective power information. When the system is started, the calibration data table which is finished in advance and stored in the system is read into the memory, the current output current information and the current output voltage information are acquired, and then the current effective power information of the system can be obtained through table lookup and simple calculation in a plurality of steps, so that the efficiency of power acquisition is improved, and further a powerful cushion is made for the improvement of the power adjustment efficiency.

In the application scenario of varicose vein ablation in this embodiment, because the residence time at each part is shorter, there is a higher requirement that the radio frequency ablation catheter can quickly reach the preset power, and in the scheme of this embodiment, the system voltage is preset for different impedance values in the pre-experiment stage, based on this, the voltage value and the current value under each impedance value are collected, the corresponding impedance coefficient and voltage coefficient are further calculated, and the impedance value, the corresponding impedance coefficient and the voltage coefficient are stored in the calibration data table, so that the system can be conveniently and reversely checked during operation, and the effective voltage and the effective current can be quickly calculated, and further the accurate detection of the power can be realized. Obviously, the system can quickly reach the designed power value to perform ablation work, and the effective power is not calculated in a manner of immediately sampling voltage and current as in the prior art, so that a large error exists, and the target power cannot be quickly reached.

Specifically, before a preset calibration data table is read into a system memory, the calibration data table needs to be obtained by experimental means, including:

s001: adjusting the impedance of an electronic load of the heating unit of the simulated ablation catheter to a target test impedance value and a target test voltage value preset when the system is adjusted to the target test impedance value;

S002: acquiring test voltage value data and test current value data of the heating unit when the target test impedance value and the target test voltage value are obtained;

s003: calculating impedance coefficient data and voltage coefficient data under a target test impedance value based on the test voltage value and the test current value;

s004: storing the target test impedance value, impedance coefficient data and voltage coefficient under the target test impedance value into the calibration data table;

s005: and adjusting the impedance of the electronic load and the voltage value of the system when the impedance value is tested according to a preset step length so as to realize the test and recording of the data in the calibration data table.

In particular, referring to FIG. 4, a method of acquiring the calibration data table is shown in one embodiment.

Firstly, the electronic load is used for simulating the impedance value X of the heating unit, and the impedance value X of the electronic load is adjusted, namely, in order to predict that different types of ablation catheters are possible to be used in a use scene, and the impedance values of the heating units of the ablation catheters of different ablation types are different, meanwhile, the fact that even the ablation catheters of the same type possibly have deviation of the heating unit is considered, and error influence caused by the deviation can be further reduced by adopting the method of the embodiment. And inquiring and adjusting the voltage value Vr of half power output of the system under the current impedance value X at the moment according to the designed power requirement, and acquiring the current sampling value Iad and the voltage sampling value Vad after the system is started. Then according to the formula: krx =vad/Iad calculates the impedance coefficient Krx at the impedance value X according to the formula: kvx =vad/Vr calculates the voltage coefficient Kvx at the impedance value X. The impedance value X, the impedance coefficient Krx at the impedance value X, and the voltage coefficient Kvx at the impedance value X are stored in the calibration data table, thereby obtaining a set of experimental data at the impedance value X. The impedance values of the electronic load are then adjusted according to a predetermined step 25 to obtain multiple sets of data. When the impedance value is greater than 500, no further experiments and data recording are performed, since 500 is already able to meet the actual impedance requirement in the varicose ablation catheter. Of course, the range of step sizes and impedance values may be further adjusted, as the case may be, and the present embodiment is merely exemplary of the choices.

As a design, in one embodiment, the step size is set to a fixed value, although the step size may be specifically adjusted to achieve the calibration data table within limited experimental data.

In another embodiment, the step size is set to a non-fixed value, for example, a step size that varies linearly, i.e., the step size varies linearly and gradually increases/decreases over a range; or, according to the step length of the nonlinear change, the nonlinear change comprises a relationship of a unitary quadratic function and a unitary cubic function, so that the nonlinear change is set in consideration of the fact that nonlinear elements exist in electronic components of the system, in order to better fit curves of an impedance value X, an impedance coefficient Krx under the impedance value X and a voltage coefficient Kvx under the impedance value X, smaller step length is adopted in a region with obvious change, larger step length is adopted in a region with gentle change, and detailed and reasonable experimental data can be provided, so that the fitting precision is improved.

Preferably, the step of searching the calibration data table according to the current impedance coefficient information, and then calculating the current impedance value information and the current voltage coefficient information by a linear method further includes: querying the calibration data table based on current impedance coefficient information to determine an impedance coefficient range and a corresponding voltage coefficient range; and calculating the current impedance value information and the current voltage coefficient by a linear method based on the current impedance coefficient information, the determined impedance coefficient range and the corresponding voltage coefficient range.

Referring to FIG. 5, in one embodiment, the calculated impedance coefficient Krx _n Look-up table is performed when the impedance coefficient Krx _n Between Krx _n-1 And Krx _n+1 Between, i.e. locking the impedance coefficient Krx _n The range of the impedance range and the voltage coefficient range are locked, and the current impedance value Xn and the current voltage coefficient Kvx are obtained by a linear method _n 。

Referring to fig. 6, a schematic diagram of a power DC-AC module is shown, where the power DC-AC module includes a high frequency switching signal circuit and a half-bridge circuit, the half-bridge circuit includes 2 power switching tubes and a frequency selecting circuit, and a main control module controls the power switching tubes to convert a direct current voltage into a square wave through the high frequency switching signal circuit, and further converts the square wave into a high frequency alternating current voltage due to the configuration of the frequency selecting circuit. Because of the dispersion of component parameters of the half-bridge circuit, the resonance frequencies of the frequency selection circuits of different systems/radio frequency generators are inconsistent, if a high-frequency pulse signal is fixed, the thermal effect of the circuit is obviously increased, the efficiency is reduced, and the high-frequency switching noise is increased, so that the work is unstable. In order to enable the high-frequency pulse signals finally output by the main control module to be matched with the resonance frequency of the frequency selection circuit, under rated load, the main control module sweeps in a certain frequency range, detects output power of all frequencies in the frequency range, and determines the frequency of the system high-frequency pulse signals when the output power is maximum, so that the low-heat effect is finally realized, the efficiency is improved, the high-frequency switching noise is reduced, and the working stability is ensured.

The main function of the power DC-DC module in the radio frequency generator is to realize the conversion from direct current voltage to direct current voltage, and the anti-interference design is critical because of the high frequency switching noise. The main control module adjusts the pulse width of the switching signal of the power DC-DC module by setting the power DC-DC module to generate an analog signal, thereby achieving the purpose of adjusting the output voltage. Due to the high-frequency switching noise, the data written into the power DC-DC module is often wrong, so that the output voltage is wrong, the actual power output is affected, and the aims of accurate and stable control are not achieved. In order to achieve the above purpose, the main control module writes the data into the power DC-DC module, reads the data to compare with the written data, and if the data is the same, allows the power DC-DC module to output corresponding analog signals, thereby generating accurate and stable switch signal pulse width and having high control precision.

Preferably, obtaining current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling to preset target power information according to the current effective power information further includes: calculating a present effective power of the heat generating unit based on effective power = effective voltage = effective current; and comparing the current effective power with the target power of the system, and adjusting the resistance value of the heating wire of the ablation catheter and/or the output voltage value of the system according to a preset program under the condition that the comparison result exceeds a preset threshold value.

According to the technical scheme, the target effective power can be quickly achieved, a negative feedback adjustment mechanism is provided on the basis, the obtained current power is compared with the target power of the system, the system can be adjusted by increasing the resistance value of the heating wire of the ablation catheter under the condition that the current power is lower than the target power and reaches a threshold value, and the heating wire is required to be a variable resistance device under the condition of course, and can also be adjusted by increasing the output power of the system. Conversely, in the event that the current power is above the target power by a threshold, the system makes an adjustment opposite to that described above. Finally, the rapid and stable control of the power of the radio frequency ablation catheter is realized.

Example two

The present embodiment provides a power control system for radio frequency ablation, comprising: the device comprises a radio frequency generator, an acquisition unit, an ablation load and a main control module, wherein: a radio frequency generator for applying a high frequency current to the ablation load; the acquisition unit is used for acquiring current output current information and output voltage information on the ablation load; the main control module further comprises: the loading module is used for reading preset calibration data form information into the system memory in the starting process of the radio frequency generator; the system comprises an acquisition module, a control module and a control module, wherein the acquisition module is used for leading high-frequency current to an ablation load by the radio frequency generator and acquiring current output current information and output voltage information on the ablation load by the acquisition unit; the calculation module is used for calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method; the control module is used for acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, the current voltage coefficient information and the current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, adjusting and controlling the current effective voltage information and the current effective current information to preset target power information according to the current effective power information, so that the ablation load quickly reaches and maintains the set power, and heating and ablation are continuously carried out on target tissues.

The power control system for radio frequency ablation of the embodiment firstly reads a calibration data table which is subjected to experiment in advance into a system memory, then acquires current output current and output voltage of the system, calculates a current impedance coefficient, looks up a table according to the calculated current impedance coefficient, calculates a current impedance value and a current voltage coefficient by using a linear method, and calculates a current effective voltage and an effective current, thereby obtaining effective power. Therefore, only when the system is started, the calibration data table which is finished in advance and stored in the system is read into the memory, the current effective power of the system can be obtained through table lookup and simple calculation of a plurality of steps after the current output current and the current output voltage are acquired, the efficiency of power acquisition is improved, positive feedback can be provided for the system rapidly, the system can achieve the preset target power rapidly, and the efficiency of tissue ablation is improved.

The main function of the power DC-DC module is to realize the conversion from direct voltage to direct voltage, and the anti-interference design is critical because of the high-frequency switching noise existing in the environment of the embodiment. The main control module adjusts the pulse width of the switching signal of the power DC-DC module by setting the power DC-DC module to generate an analog signal, thereby achieving the purpose of adjusting the output voltage, effectively avoiding high-frequency switching noise and improving the anti-interference performance.

In one embodiment, the system further comprises a temperature acquisition module for acquiring the temperature of the ablation load and transmitting to the master control module.

In one embodiment, the system further comprises a touch screen module in signal connection with the master control module and configured to receive parameter settings of a user.

In one embodiment, the system further comprises a power supply module for supplying power to the modules in the system that need to be powered.

Correspondingly, the embodiment also provides a power control method for radio frequency ablation, which comprises the following steps: in the starting process of the radio frequency generator, the main control module reads preset calibration data form information into a system memory; the radio frequency generator is used for supplying high-frequency current to an ablation load, and collecting current output current information and output voltage information on the ablation load through the collecting unit; calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method; acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling the current effective power information to preset target power information according to the current effective power information, so that the ablation load quickly reaches set power and is maintained, and heating and ablation are continuously carried out on target tissues.

The embodiment reads a calibration data table which is subjected to experiments in advance into a system memory, then acquires the current output current and output voltage of the system, calculates the current impedance coefficient, looks up a table according to the calculated current impedance coefficient, calculates the current impedance value and the current voltage coefficient by using a linear method, and calculates the current effective voltage and the effective current to obtain effective power. Therefore, only when the system is started, the calibration data table which is finished in advance and stored in the system is read into the memory, the current output current and the current output voltage are collected, and then the table is checked and calculated simply in a plurality of steps, so that the current effective power of the system can be obtained, the efficiency of power collection is improved, positive feedback can be provided for the system rapidly, and the system can achieve the preset target power rapidly.

In this embodiment, the impedance value in the calibration data table may be adjusted by using a fixed step length, so that the calibration data table may be obtained in limited experimental data; in addition, the impedance value in the calibration data table adopts the step length of linear change or nonlinear change, the smaller step length is adopted in the region with obvious change, and the larger step length is adopted in the region with gentle change, so that detailed and reasonable experimental data can be provided, and the fitting precision is improved.

Aiming at each system, the invention considers that the dispersion of component parameters in the half-bridge circuit exists, so that the resonance frequency of the frequency selection circuits of different systems is inconsistent, the single high-frequency pulse signal can cause the obvious increase of the thermal effect of part of the circuits for different systems, the efficiency is reduced, the high-frequency switching noise is increased, thus the working is unstable, the main control module sweeps in the preset frequency range to detect the output power of all frequencies in the frequency range, and the frequency when the output power is maximum is determined as the frequency of the high-frequency pulse signal of the system. Therefore, the low thermal effect is finally realized, the efficiency is improved, the high-frequency switching noise is reduced, and the working stability is ensured.

According to the invention, the main control module adjusts the pulse width of the switching signal of the power DC-DC module by setting the power DC-DC module to generate the analog signal, so that the aim of adjusting the output voltage is fulfilled, high-frequency switching noise can be effectively avoided, and the anti-interference performance is improved.

According to the invention, the main control module writes the data into the power DC-DC module, reads out the data which are compared with the written data, and if the data are the same, allows the power DC-DC module to output corresponding analog signals, so that accurate and stable switch signal pulse width is generated, and the control precision is high.

Those of ordinary skill in the art will appreciate that: all or part of the steps for implementing the above method embodiments may be implemented by hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, where the program, when executed, performs steps including the above method embodiments; and the aforementioned storage medium includes: a mobile storage device, a Read Only Memory (ROM), a magnetic disk or an optical disk, or the like, which can store program codes.

The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, it is within the scope of the appended claims and their equivalents to fall within the scope of the invention.

Claims

1. A method for controlling the power of a varicose radiofrequency ablation catheter, comprising the steps of:

in the starting process of the radio frequency generator, the main control module reads preset calibration data form information into a system memory;

the radio frequency generator is used for supplying high-frequency current to the heating unit in the catheter, and the current output current information and output voltage information on the heating unit are collected through the collecting unit;

calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method;

acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling to preset target power information according to the current effective power information, so that the heating unit can quickly reach set power and maintain the set power, and continuously heating the vein wall to shrink the vein wall collagen.

2. The power control method of claim 1, further comprising, prior to reading the predetermined calibration data table information into the system memory:

adjusting the impedance of an electronic load of the heating unit of the simulated ablation catheter to a target test impedance value and a target test voltage value preset when the system is adjusted to the target test impedance value;

acquiring test voltage value data and test current value data of the heating unit when the target test impedance value and the target test voltage value are obtained;

calculating impedance coefficient data and voltage coefficient data under a target test impedance value based on the test voltage value data and the test current value data;

storing the target test impedance value, impedance coefficient data and voltage coefficient data under the target test impedance value into the calibration data table;

and adjusting the impedance of the electronic load and the voltage value of the system when the impedance value is tested according to a preset step length so as to realize the test and recording of the data in the calibration data table.

3. The power control method of claim 2, wherein the method further comprises:

adjusting the impedance value of the electronic load according to a preset fixed step length; or, adjusting the impedance value of the electronic load according to the step length which satisfies the change of a preset functional relation;

And ending the test to finish the calibration data table under the condition that the impedance value of the electronic load is larger than a preset threshold value.

4. The power control method according to claim 1, wherein the step of searching the calibration data table based on the current impedance coefficient information and then calculating the current impedance value information and the current voltage coefficient information by a linear method further comprises:

querying the calibration data table information based on current impedance coefficient information to determine an impedance coefficient range and a corresponding voltage coefficient range;

and calculating a current impedance value and a current voltage coefficient by a linear method based on the current impedance coefficient information, the determined impedance coefficient range and the corresponding voltage coefficient range.

5. The method of claim 1, wherein the method of applying a high frequency current by the radio frequency generator to the heat generating unit within the conduit further comprises:

the main control module inputs a high-frequency pulse signal to a high-frequency switch signal circuit in a power DC-AC module of the radio frequency generator so as to control a half-bridge circuit in the power DC-AC module to convert direct-current voltage into square waves;

converting the square wave into a high-frequency alternating voltage through a frequency selecting circuit in the half-bridge circuit;

The main control module sweeps in a preset frequency range under rated load to detect output power of all frequencies in the frequency range, and the frequency when the output power is maximum is determined to be the frequency of the high-frequency pulse signal of the system.

6. The method of claim 5, wherein the rf generator supplying a high frequency current to a heat generating unit within the conduit further comprises: the power DC-DC module in the radio frequency generator generates an analog signal to adjust the pulse width of a switching signal of the power DC-DC module so as to realize the adjustment of output voltage, wherein after the main control module writes the data of the power DC-DC module, the main control module reads the data from the power DC-DC module and compares the data with the written original data, and if the data are the same, the power DC-DC module outputs a corresponding analog signal.

7. The power control method according to claim 1, wherein obtaining current effective power information based on the current effective voltage information and the current effective current information, and performing adjustment control to preset target power information according to the current effective power information further comprises:

calculating a present effective power of the heat generating unit based on effective power = effective voltage = effective current;

And comparing the current effective power information with the target power information of the heating unit, and adjusting the resistance value of the heating unit of the ablation catheter and/or the output voltage value of the system according to a preset program under the condition that the comparison result exceeds a preset threshold value.

8. The utility model provides a varicosity radio frequency ablation catheter's power control system which characterized in that includes radiofrequency generator, collection unit, heating element, main control module, wherein:

the radio frequency generator is used for supplying high-frequency current to the heating unit in the catheter;

the acquisition unit is used for acquiring the current output current information and the current output voltage information on the heating unit;

the main control module further comprises:

the loading module is used for reading preset calibration data form information into the system memory in the starting process of the radio frequency generator;

the acquisition module is used for leading the high-frequency current to the heating unit in the catheter by the radio-frequency generator and acquiring the current output current information and output voltage information on the heating unit by the acquisition unit;

the calculation module is used for calculating current impedance coefficient information based on the output current information and the output voltage information, inquiring the calibration data table according to the current impedance coefficient information, and then calculating current impedance value information and current voltage coefficient information through a linear method;

The control module is used for acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, adjusting and controlling the current effective power information to preset target power information according to the current effective power information, enabling the heating unit to quickly reach set power and maintain the set power, and continuously heating the vein wall to enable the vein wall collagen to shrink.

9. The power control system of claim 8, wherein the radio frequency generator further comprises: the main control module controls the power DC-DC module to generate an analog signal to adjust the switching signal pulse of the power DC-DC module, so that the purpose of adjusting output voltage is achieved, and the power DC-AC module is connected with the radio frequency ablation catheter through a catheter interface module.

10. The power control system of claim 9, wherein the power DC-AC module further comprises: the high-frequency switch signal circuit is used for generating a power switch tube signal for driving the DC-AC half-bridge circuit so as to convert the realized direct-current voltage into square waves, and then the square waves are converted into high-frequency alternating-current voltage through a frequency selection circuit in the DC-AC half-bridge circuit; in the system debugging stage, the main control module sweeps in a certain frequency range, detects output power of all frequencies in the frequency range, and determines the frequency with the maximum output power as the frequency of the final high-frequency pulse signal so as to realize the efficiency optimization of the system.

11. The power control system of claim 9, wherein the master control module writes data to the power DC-DC module, and reads the data from the power DC-DC module to compare with the written original data, and if the data is the same, the power DC-DC module outputs a corresponding analog signal.

12. The power control system of claim 8, further comprising a temperature acquisition module for acquiring the temperature of the heating element within the radiofrequency ablation catheter and transmitting to the master control module.

13. The power control system of claim 8, further comprising a touch screen module in signal communication with the master control module and configured to receive user parameter settings.

14. The power control system of claim 8, further comprising a power module for powering a module in the system that requires power.

15. A power control method for radio frequency ablation, comprising the steps of:

The radio frequency generator is used for supplying high-frequency current to an ablation load, and collecting current output current information and output voltage information on the ablation load through the collecting unit;

acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, current voltage coefficient information and current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, and adjusting and controlling the current effective power information to preset target power information according to the current effective power information, so that the ablation load quickly reaches set power and is maintained, and heating and ablation are continuously carried out on target tissues.

16. A power control system for radio frequency ablation, comprising: the device comprises a radio frequency generator, an acquisition unit, an ablation load and a main control module, wherein:

a radio frequency generator for applying a high frequency current to the ablation load;

The acquisition unit is used for acquiring current output current information and output voltage information on the ablation load;

the main control module further comprises:

the system comprises an acquisition module, a control module and a control module, wherein the acquisition module is used for leading high-frequency current to an ablation load by the radio frequency generator and acquiring current output current information and output voltage information on the ablation load by the acquisition unit;

the control module is used for acquiring current effective voltage information and current effective current information based on the acquired current output voltage information, the current voltage coefficient information and the current impedance value information, acquiring current effective power information based on the current effective voltage information and the current effective current information, adjusting and controlling the current effective voltage information and the current effective current information to preset target power information according to the current effective power information, so that the ablation load quickly reaches and maintains the set power, and heating and ablation are continuously carried out on target tissues.

17. A computer device, comprising:

a memory for storing a processing program;

a processor which, when executing the treatment program, implements the power control method for a varicose radiofrequency ablation catheter as claimed in any one of claims 1 to 7 or the power control method for radiofrequency ablation as claimed in claim 15.