High-frequency surgical instrument and tissue intelligent contact discrimination system

Abstract

The invention belongs to the technical field of high-frequency electrosurgical equipment and control, and particularly discloses and provides a high-frequency surgical instrument and tissue intelligent contact screening system which comprises the steps that a detection electric field is established by applying asymmetric biphase diagnosis pulses, and transient residual voltage signals are collected in a measurement dead zone. The digital signal is used for calculating a dielectric absorption quantization parameter, the dielectric absorption quantization parameter is compared with a threshold value according to the digital signal, and an effective tissue contact state or a conductive liquid contact state is classified; the analog signal directly generates an analog control voltage. When a main output instruction is received, the analog control voltage does not need any digital processing, the high-frequency energy output stage is directly modulated in a continuous and proportional mode, instant self-adaptive closed-loop energy control based on real-time contact quality is achieved, and the safety and effectiveness of an operation are improved.

Description

Technical Field

[0001] This invention belongs to the technical field of high-frequency electrosurgical equipment and control, and relates to a high-frequency surgical instrument and tissue intelligent contact identification system. Background Technology

[0002] In modern surgery, high-frequency surgical devices apply high-frequency currents to surgical instruments to cut and coagulate biological tissues. To ensure the safety and effectiveness of the procedure, a core technical challenge lies in optimizing the timing and dosage of energy release. A crucial prerequisite is that the system can accurately sense the contact state between the instrument tip and the target tissue. Activating energy output when the instrument is suspended in the air or accidentally contacts a non-target conductive medium may cause arcing that could damage surrounding tissues, or lead to poor surgical outcomes due to energy dissipation in the conductive liquid. These factors necessitate the system's intelligent recognition capabilities.

[0003] To address this challenge, a commonly used technical solution in the industry is based on real-time impedance monitoring. This method applies a low-amplitude probe signal to both ends of the electrodes of the surgical instrument and continuously measures the impedance value of the circuit between them. The system has one or more preset impedance ranges representing normal tissue contact. When the real-time measured impedance value falls within this preset range, the system determines it as valid contact, thus allowing the output of high-frequency energy. This method utilizes the relatively stable impedance characteristics exhibited by biological tissue at specific frequencies as a criterion, and can, to some extent, distinguish between instrument suspension and contact.

[0004] However, relying solely on a single static impedance value as a criterion has inherent limitations. For example, during surgery, conductive fluids such as blood and saline used for irrigation may have impedance values ​​similar to or overlapping with those of certain biological tissues under specific conditions. This can cause ambiguity in identification, and the system may misclassify conductive fluids as valid tissue, leading to ineffective or even dangerous energy output. Furthermore, simple impedance measurements cannot fully reflect the complex electrophysiological characteristics of tissues, especially failing to characterize the capacitive effects caused by cell membrane structures. Therefore, its information dimension is limited in assessing the quality of instrument-tissue contact, and it needs improvement in complex surgical scenarios requiring real-time energy regulation.

[0005] Based on the above problems, the present invention aims to solve the problem of identification ambiguity that may occur when the prior art distinguishes between biological tissues and non-tissue conductive media by relying solely on impedance measurement. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art and to achieve the above objectives, the present invention proposes the following technical solution: a high-frequency surgical instrument and tissue intelligent contact identification system, comprising: a diagnostic pulse generation module, used to generate and apply an asymmetric biphasic diagnostic pulse sequence to the tip of the surgical instrument to establish a polarized electric field for dielectric property detection at the contact interface.

[0007] The signal acquisition module is used to receive electrical signals from the tip of the surgical instrument. Within the measurement dead phase of the diagnostic pulse sequence, it acquires the transient residual voltage signal formed by the attenuation of the charge at the contact interface and splits the signal into two outputs: one is a digitized transient residual voltage signal, and the other is an undigitized analog transient residual voltage signal.

[0008] The parameter calculation module is used to receive transient residual voltage signals and calculate and quantize dielectric absorption quantization parameters that characterize the dielectric absorption capability of the target material based on these signals.

[0009] The analog control voltage generation module is used to receive the analog transient residual voltage signal and generate the analog control voltage according to the amplitude of the signal at a preset time point.

[0010] The contact state classification module is used to receive dielectric absorption quantization parameters and classify the contact state based on the comparison result of the parameters with a preset threshold, so as to generate contact state classification results for human-computer interaction display. The contact state includes effective tissue contact and non-tissue conductive medium contact.

[0011] The control logic module is used to generate an energy output enable signal when it receives the operator's main output command and simultaneously confirms that the contact status classification result is effective tissue contact.

[0012] The energy output modulation module is used to perform analog modulation on the high-frequency surgical energy output stage using analog control voltage when receiving the main output command.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention can capture and quantify characteristic parameters reflecting the dielectric absorption capacity of the target material by applying asymmetric biphasic diagnostic pulses and collecting and analyzing transient residual voltage signals of the contact interface in the measurement dead phase. Since biological tissues and conductive liquids have different physical properties, the former decays slowly and the latter dissipates rapidly, so this parameter can distinguish between the two. This method is based on the internal electrophysiological characteristics of the material rather than a single impedance value for discrimination, so it can still provide a basis for differentiation when the impedances of the two are similar.

[0014] (2) This invention establishes an independent analog signal processing path to directly input the undigitized transient residual voltage signal into the sample-and-hold circuit, generating an analog control voltage. The amplitude of this voltage directly corresponds to the charge retention level of the material. This voltage is used as the physical gating signal for the high-frequency energy output power stage, thereby bypassing the conventional digital processing link. This design makes the system's safety interlock response speed depend on the physical characteristics of the analog components, rather than the software execution time, thus directly converting the physical detection results into physical-level constraints on energy output, enhancing the directness and reliability of energy output safety control.

[0015] (3) This invention introduces a dual security verification mechanism, using the contact state classification result in the digital domain as the permission gate for energy output. Only when valid tissue contact is confirmed will the system be allowed to enter the energy output preparation state. On this basis, the energy is then modulated in real time and proportionally by the hardware-level control voltage in the analog domain. This closed-loop control strategy aims to reduce the risk of erroneous energy output on non-target media, thereby helping to improve the safety of the surgery. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the system module connections of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] Please see Figure 1 As shown, the present invention proposes a high-frequency surgical instrument and tissue intelligent contact identification system, comprising: a diagnostic pulse generation module, a signal acquisition module, a parameter calculation module, an analog control voltage generation module, a contact state classification module, a control logic module, and an energy output modulation module.

[0020] The diagnostic pulse generation module is used to generate and apply an asymmetric biphasic diagnostic pulse sequence to the tip of the surgical instrument to establish a polarized electric field at the contact interface for dielectric property detection.

[0021] In a preferred embodiment, an asymmetric biphasic diagnostic pulse sequence is generated and applied to the tip of a surgical instrument to establish a polarized electric field at the contact interface for dielectric property detection. This includes activating a pulse generation unit and outputting an asymmetric biphasic diagnostic pulse sequence to the electrodes of a high-frequency surgical instrument, each cycle of which consists of a positive charging phase and a subsequent measurement dead zone phase.

[0022] The voltage amplitude of the positive charging phase is controlled to be lower than the preset depolarization threshold of biological tissue cell membranes.

[0023] By applying an asymmetric biphasic diagnostic pulse sequence to the tip of a surgical instrument, a transient polarized electric field is established between the instrument tip and the target material it contacts.

[0024] Specifically, the diagnostic pulse control module can be implemented using a field-programmable gate array (FPGA) or a microcontroller equipped with a dedicated timer peripheral, which initiates an internal pulse generation unit. This pulse generation unit outputs a periodic asymmetric biphasic diagnostic pulse sequence to the electrode drive stage of the high-frequency surgical instrument via a digital-to-analog converter (DAC) or a programmable waveform generator. Each cycle of this asymmetric biphasic diagnostic pulse sequence consists of a positive charging phase driven by an active voltage and a subsequent measurement dead zone phase in which the output switches to a high-impedance state to allow the contact interface capacitance to discharge naturally.

[0025] During the forward charging phase, the pulse generation unit outputs a stable forward DC voltage, the duration of which is the charging duration parameter. Its value is usually set between 10µs and 100µs, which is sufficient to effectively charge the equivalent interface capacitance of biological tissue.

[0026] When measuring the dead-time phase, the pulse generation unit immediately switches the output to a high-impedance state for a duration equal to the dead-time parameter. This completes one cycle of pulse transmission. The dead time parameter is typically set between 100µs and 500µs, which is sufficient to observe the significant differences in charge decay caused by the dielectric properties of different materials.

[0027] Throughout the process, before generating the asymmetric biphasic diagnostic pulse sequence, the diagnostic pulse control module reads the preset cell membrane depolarization threshold voltage from a non-volatile memory. And ensure the voltage amplitude of the positive charging phase. Always below the cell membrane depolarization threshold voltage This control ensures that the applied pulse is used only to probe the dielectric properties of the target material without triggering any cellular electrophysiological response, thus constituting a non-therapeutic probe.

[0028] Cell membrane depolarization threshold voltage This is a key physiological parameter characterizing the excitability of biological cells. In this embodiment, the threshold is set based on publicly available electrophysiological standards, with typical values ​​ranging from 50mV to 100mV. To ensure non-invasive detection, the voltage amplitude of the positive charging phase... It is strictly controlled below 1V, for example, 200mV to 800mV. This setting ensures the signal-to-noise ratio while being far below any level that could cause thermal damage or electrical stimulation to the tissue.

[0029] Finally, the asymmetric biphasic diagnostic pulse sequence is applied to the tip electrode of the surgical instrument through an output buffer circuit. When the tip electrode contacts the target material, the forward charging phase establishes a transient polarization electric field at the contact interface. This electric field causes a redistribution of charges within the target material, which are then bound within the interface capacitance. This provides the necessary physical basis for capturing the dielectric response signal of the material in subsequent steps. A transient polarization electric field is a temporary electric field formed at the contact interface due to the application of an external voltage, resulting in dipole orientation or free charge accumulation. The establishment and disappearance of this electric field directly reflects the dielectric properties of the target material.

[0030] For example, in a specific application scenario of this step, the preset parameter loaded by the system from the non-volatile memory is: charging time parameter. The dead time parameter is set to 50µs. The cell membrane depolarization threshold voltage is set to 250 µs. Set to 100mV. The diagnostic pulse control module sets the voltage amplitude for the positive charging phase. The voltage is set at 800mV. First, the diagnostic pulse control module confirms that the set 800mV voltage amplitude is below the electrophysiological safety threshold that could cause tissue damage, and also confirms that operating at this low voltage constitutes non-therapeutic detection. Next, the pulse generation unit begins generating and outputting an asymmetric biphasic diagnostic pulse sequence. At the beginning of each cycle, the pulse generation unit outputs a +800mV holding DC voltage for 50µs. During this period, if the surgical instrument tip has contacted biological tissue, the equivalent capacitance of the tissue cell membrane will be charged. Subsequently, at 50µs, the output of the pulse generation unit immediately switches to a high-impedance state and maintains this state for 250µs. This process establishes a transient polarized electric field maintained by trapped charges at the contact interface; the state of this electric field will be used for dielectric property analysis in subsequent steps. The entire pulse sequence has a period of 50µs + 250µs = 300µs, repeating continuously at a frequency of approximately 3.33kHz, thus providing the system with continuous contact state detection.

[0031] The signal acquisition module is used to receive electrical signals from the tip of the surgical instrument, acquire transient residual voltage signals formed by the attenuation of charge at the contact interface within the measurement dead phase of the diagnostic pulse sequence, and output the signals in two ways: one is a digitized transient residual voltage signal, and the other is an undigitized analog transient residual voltage signal.

[0032] In a preferred embodiment, acquiring the transient residual voltage signal formed by the decay of the charge at the contact interface includes: after the positive charging phase ends, activating a signal buffer circuit connected in parallel with the surgical instrument electrode during the measurement dead zone phase.

[0033] Using a signal buffer circuit, the voltage decay curve caused by the natural release of stored charge at the interface is captured in real time and input to a signal distribution node.

[0034] The first output of the signal distribution node is connected to an analog-to-digital converter to generate a digital transient residual voltage signal containing time-domain information of the complete attenuation process.

[0035] The second output of the signal distribution node is transmitted directly as an undigitized analog transient residual voltage signal.

[0036] Specifically, at the instant the dead-zone phase measurement begins, a signal acquisition and processing module synchronized with the diagnostic pulse control module is immediately triggered. First, the signal acquisition and processing module activates a signal buffer circuit connected in parallel with the surgical instrument electrodes via a high-speed analog switch. This signal buffer circuit, centered on a unity-gain buffer amplifier, has an input impedance set to no less than 1 GΩ. It is used to continuously and non-invasively monitor the tip electrode voltage throughout the entire dead-zone phase measurement, thereby avoiding disturbances to the natural decay process of the charge at the contact interface.

[0037] Next, the output of the unity-gain buffer amplifier, i.e., the original analog transient residual voltage signal, is fed to a signal distribution node, and thus split into two parallel processing paths: The first path is the digital processing path: the analog signal is fed to a high-speed analog-to-digital converter (ADC). The ADC samples and quantizes the continuous voltage decay curve at a preset sampling frequency (typically 1MHz to 10MHz) and quantization bit depth (typically 12-bit or 16-bit), generating an array consisting of a series of discrete digital values. This array completely records the time-domain information of the voltage decay process, is defined as a digitized transient residual voltage signal, and is temporarily stored in a dual-port random access memory (DPRAM) for processing by the parameter calculation module. The shape of this signal directly reflects the charge retention capability of the target material.

[0038] The voltage decay curve is caused by the natural release of polarization charge stored at the contact interface through the impedance of the target material itself within the measurement dead phase. Its shape, especially the decay rate related to the RC time constant, directly reflects the charge retention capability of the target material.

[0039] The transient residual voltage signal is a digital data structure, specifically a one-dimensional array. Each element of the array corresponds to the quantized voltage value at a sampling time. The length of the array is determined by the duration of the measurement dead phase and the sampling frequency.

[0040] The second path is the analog control path: the raw, undigitized analog transient residual voltage signal is directly transmitted to the analog control voltage generation module. In this module, the analog signal is used as input to sample its amplitude at specific times and generate an analog control voltage that can be directly applied to the hardware without digital processing.

[0041] Through this dual-path design, the system achieves parallel processing of the same physical signal source: one path is used for state classification and discrimination through reliable calculation, while the other path is used to achieve fast and continuous analog closed-loop control.

[0042] For example, immediately following the aforementioned steps, at the 50µs mark of each pulse cycle, the forward charging phase ends, and the measurement dead-zone phase begins and lasts for 250µs. At this time, the signal acquisition and processing module is synchronously triggered. The ADC used in the module has a sampling frequency of 2MHz, i.e., sampling once every 0.5µs, a quantization bit depth of 12 bits, and a reference voltage of 1.0V. Assume that in one scenario, the tip of the surgical instrument is in contact with biological tissue, where charge decay is slower due to cell membrane capacitance. At that time, the initial voltage captured by the signal buffer circuit was 750mV, and the digital value obtained after ADC conversion was... As time went on, in That is, when the dead-zone phase measurement ends, the voltage decays to 150mV, and the corresponding digital value is... Ultimately, the transient residual voltage signal generated and stored by the system is a one-dimensional array containing 500 sampling points, its value gradually decreasing from approximately 3071 to 614. In another scenario, if the instrument tip contacts conductive saline solution, which exhibits near-pure resistivity, the charge will dissipate instantaneously. After capturing an initial voltage of 750mV, it may only take 1µs, i.e. At this point, the voltage has decayed to below the minimum resolution voltage of the ADC, and the voltage at all subsequent sampling points is 0mV. Therefore, the first or first few elements of the one-dimensional array corresponding to the transient residual voltage signal generated in this scenario are non-zero, while the vast majority of the remaining elements are 0.

[0043] The parameter calculation module is used to receive transient residual voltage signals and calculate and quantify dielectric absorption quantization parameters that characterize the dielectric absorption capability of the target material based on the signals.

[0044] In a preferred embodiment, the dielectric absorption quantization parameters characterizing the dielectric absorption capability of the target material are calculated and quantified, including: analyzing the transient residual voltage signal, extracting the initial voltage value at the start of the measurement dead phase, and the terminal voltage value at the end of the preset time window.

[0045] The initial voltage holding rate is obtained by calculating the ratio of the terminal voltage value to the initial voltage value.

[0046] In a further preferred embodiment, calculating and quantifying the dielectric absorption quantization parameters characterizing the dielectric absorption capability of the target material further includes: obtaining preset normalized calibration parameters.

[0047] The initial voltage retention rate is normalized using normalized calibration parameters to generate standardized dielectric absorption quantization parameters.

[0048] Specifically, the parameter calculation module reads the complete transient residual voltage signal array from the dual-port random access memory (DPRAM). Next, this unit analyzes the transient residual voltage signal, extracting two key data points: the first data point is the initial voltage value at the start of the dead-zone phase, i.e. At the first moment, this value is directly taken from the first element of the transient residual voltage signal array. The second data point is the terminal voltage value at the end of a preset time window, taken from the last element of the transient residual voltage signal array. The duration of this time window is equal to the dead time parameter. The time period. Therefore, the terminal voltage value is within... The digital result of the voltage measured at a given time.

[0049] Subsequently, the parameter calculation module performs a floating-point division operation to obtain an initial voltage retention rate by calculating the ratio of the terminal voltage value to the initial voltage value. This initial voltage retention rate directly reflects the ability of the contact interface to store charge within a specified time window; a higher value indicates slower charge dissipation.

[0050] Finally, the parameter calculation module calls the normalized calibration parameters stored in non-volatile memory to perform linear mapping on the initial voltage retention rate, generating a dielectric absorption quantization parameter constrained within a standard range to characterize the dielectric absorption capability of the target material. This parameter is then output to a dedicated data register as the basis for subsequent state identification steps. The dielectric absorption quantization parameter is a dimensionless floating-point number, its value normalized to the range of 0 to 1, and its magnitude is positively correlated with the dielectric absorption capability of the target material.

[0051] The calculations involved in this step can be characterized by the following two formulas. First, the initial voltage retention rate. The calculation formula is:

[0052] Secondly, dielectric absorption quantization parameters The normalization formula is:

[0053] in, This represents the initial voltage value extracted from the transient residual voltage signal at the start of the measurement dead-zone phase. This represents the terminal voltage value extracted from the transient residual voltage signal at the end of the preset time window. This is the calculated initial voltage retention rate, which is a dimensionless scalar with a value between 0 and 1. These are the final generated dielectric absorption quantization parameters. and These are the preset normalization lower and upper reference values.

[0054] Normalization is a mathematical transformation that maps raw data to a specific range. This embodiment uses linear normalization to ensure that the final output parameters are unaffected by fluctuations in the initial charging voltage amplitude. (Reference value for the lower limit of normalization) This is based on extensive experimental measurements when in contact with a purely conductive medium, such as physiological saline. The statistical average is set, and its theoretical value is close to 0. Reference value for the upper limit of normalization. It is based on experimental measurements when in contact with biological tissue types known to have the strongest dielectric absorption capacity, such as adipose tissue. The statistical average is set, and its typical value ranges from 0.3 to 0.5.

[0055] For example, continuing with the scenario where the surgical instrument tip contacts biological tissue as described above, the parameter calculation module reads an array of transient residual voltage signals containing 500 sampling points. First, this unit extracts the first element of the array as the initial voltage value. Its value is 3071. Next, the unit defines a preset time window as the entire 250µs measurement dead zone and extracts the 500th element of the array as the terminal voltage value. Its value is 614. Subsequently, the parameter calculation module calculates the initial voltage holding rate, the calculation process of which is as follows: To perform normalization, the unit loads preset calibration parameters from non-volatile memory, assuming a normalization lower limit reference value. The value is 0.01, which is the upper limit of the normalization reference value. The value is 0.40. Finally, this unit calculates and generates the dielectric absorption quantization parameter, the specific calculation process of which is as follows: The calculated value of 0.487 is stored in the designated data register to characterize the target material currently in contact with as having moderate dielectric absorption capacity.

[0056] The analog control voltage generation module is used to receive an analog transient residual voltage signal and generate an analog control voltage based on the amplitude of the signal at a preset time point.

[0057] In a preferred embodiment, generating an analog control voltage includes: inputting an analog transient residual voltage signal to a sample-and-hold circuit that is synchronously triggered with an asymmetric biphase diagnostic pulse sequence.

[0058] The sample-and-hold circuit samples the amplitude of the analog transient residual voltage signal at a preset sampling delay time point within the measurement dead zone phase, outputs a holding DC voltage proportional to the sampling amplitude, and uses this holding DC voltage as the analog control voltage.

[0059] Specifically, within the measurement dead-zone phase, the continuous analog voltage decay curve output by the signal buffer circuit without analog-to-digital conversion—that is, the physical analog form of the transient residual voltage signal—is directly input to a sample-and-hold circuit that is synchronously triggered with the diagnostic pulse sequence. Synchronous triggering means that the sampling action of the sample-and-hold circuit is strictly controlled by the timing logic of the diagnostic pulse sequence, ensuring that each sampling occurs at the same relative time point within the measurement dead-zone phase. The sample-and-hold circuit is an analog functional circuit, typically composed of a high-speed analog switch, a low-leakage holding capacitor, and a unity-gain operational amplifier. Its core function is to capture the instantaneous value of a rapidly changing analog signal at a specific moment and maintain it as a stable DC level for a period of time.

[0060] A specific time is determined by a preset sampling delay time. It is confirmed that the value range of this parameter is from 0 to the dead zone duration parameter. Between, its value is set to be close to For example, 0.8 times This is to maximize the differentiation of voltage attenuation differences between different materials.

[0061] Secondly, a master timing control unit, such as the aforementioned FPGA, sends a sampling trigger pulse to the sample-and-hold circuit at a preset sampling delay time point after the start of the dead-zone phase measurement. Upon receiving the sampling trigger pulse, the sample-and-hold circuit immediately samples the real-time analog amplitude of the input transient residual voltage signal and locks it onto an internal holding capacitor.

[0062] Finally, a high-impedance output buffer isolates and outputs the voltage across the holding capacitor, thereby generating a stable DC voltage. This holding DC voltage is defined as the analog control voltage, whose DC amplitude directly and physically maps the charge holding level of the target material at a specific moment. The entire generation process is completed in the analog domain without the intervention of any software algorithm or calculation by a digital signal processor.

[0063] Analog control voltage The generation process of can be described by the following relation:

[0064] in, It is the amplitude of the final output analog control voltage. It is the total gain coefficient of the sample-and-hold circuit and its output buffer stage. In this embodiment, the coefficient is preset to 1, and its design goal is to replicate the input voltage without changing its amplitude. It is based on time This is a function that returns the simulated value of the transient residual voltage at that moment, with the variable being the independent variable. It is the duration of the positive charging phase. This is the preset sampling delay time, starting from the beginning of the measurement dead-zone phase. Therefore, Together, they define the absolute time point from the start of a diagnostic pulse cycle to the execution of sampling. The analog control voltage is a continuous analog signal whose voltage value is updated once at the sampling moment of each diagnostic pulse cycle and remains constant until the next sampling moment arrives, thus forming a stepped DC level signal.

[0065] For example, continuing with the example data and scenario from the previous steps, the sample-and-hold circuit receives the same analog voltage decay curve from the signal buffer circuit as the ADC. The system has a preset sampling delay time. It is 200µs. Therefore, the first pulse after the start of each diagnostic pulse cycle... At a certain moment, the main timing control unit generates a narrow pulse to trigger sampling. When the tip of the surgical instrument contacts the biological tissue, its voltage decay curve... The instantaneous analog voltage value at time 207mV is 207mV. At this moment, the analog switch of the sample-and-hold circuit momentarily opens after closing, charging this 207mV voltage value and holding it on the internal capacitor. After passing through the output buffer stage, the system finally outputs a stable 207mV DC voltage as the analog control voltage. This voltage will be maintained until it is updated by a new sample value at 250µs of the next pulse cycle. Conversely, when the instrument tip contacts the saline solution, its voltage decays to 0V within a few microseconds. Therefore, when sampling is performed at 250µs, the sampled voltage is 0V, and the sample-and-hold circuit correspondingly outputs a 0V analog control voltage.

[0066] The contact state classification module is used to receive dielectric absorption quantization parameters and classify the contact state according to the comparison result of the parameters and a preset threshold, so as to generate a contact state classification result for human-computer interaction display. The contact state includes effective tissue contact and non-tissue conductive medium contact.

[0067] In a preferred embodiment, a dielectric absorption quantization parameter is received, and the contact state is classified and judged based on the comparison result of the parameter and a preset threshold to generate a contact state classification result for human-computer interaction display. This includes: comparing the dielectric absorption quantization parameter with a preset material property threshold, which includes a first high threshold for defining biological tissue and a second low threshold for defining conductive liquid.

[0068] If the dielectric absorption quantization parameter is greater than the first high-order threshold, the current contact state is determined to be an effective tissue contact.

[0069] If the dielectric absorption quantization parameter is lower than the second lowest threshold, it is determined to be a non-organic conductive dielectric contact.

[0070] In a further preferred embodiment, a dielectric absorption quantization parameter is received, and the contact state is classified and judged based on the comparison result of the parameter and a preset threshold to generate a contact state classification result for human-computer interaction display. The method also includes generating a corresponding digital code based on the determined state of effective tissue contact or non-tissue conductive medium contact.

[0071] The output identifies the contact status classification results, which are used by the human-computer interaction unit for status display or log recording.

[0072] Specifically, after the dielectric absorption quantization parameters are generated, a contact state discrimination module running within the central processing unit is immediately executed. First, the contact state discrimination module reads the latest dielectric absorption quantization parameters from a dedicated data register. Simultaneously, this module retrieves two preset material property thresholds from the system's non-volatile configuration memory. These material property thresholds serve as decision boundaries for contact state classification: a first high threshold for defining biological tissue and a second low threshold for defining conductive liquids.

[0073] First high-order threshold It is a dimensionless value. It is set based on the distribution range of the dielectric absorption quantization parameter of various biological tissue samples after conducting a large number of in vitro and in vivo experiments. It is a lower limit value that can effectively distinguish the vast majority of tissue samples from non-tissue media. Its typical value range is 0.35 to 0.50.

[0074] Second lowest threshold It is also a dimensionless value, which is set based on the statistical analysis of the dielectric absorption quantification parameters of common intraoperative conductive fluids such as blood and saline. It is an upper limit value that can reliably identify such media, and its typical value range is 0.05 to 0.15.

[0075] Next, the contact state determination module executes a conditional judgment logic sequence. This module first compares the read dielectric absorption quantization parameter with a first high-order threshold: if the dielectric absorption quantization parameter is greater than the first high-order threshold, the current contact state is determined to be a valid tissue contact; if this condition is not met, the module continues to compare the dielectric absorption quantization parameter with a second low-order threshold; if the parameter is lower than the second low-order threshold, it is determined to be a non-tissue conductive dielectric contact; if neither of the above two conditions is met, i.e., the value of the dielectric absorption quantization parameter is between the two thresholds, it is determined to be a suspended or invalid contact state.

[0076] Finally, based on the determination result, the contact state discrimination module generates a corresponding numerical code as the contact state classification result and writes it into a shared memory area connected to the main control unit. Subsequently, the main control unit drives the human-machine interaction unit to display the status and / or execute event log recording based on this code.

[0077] The contact state classification result is a standardized data identifier, such as an 8-bit unsigned integer, in which different values ​​are predefined to represent different contact states, such as 0x01 representing effective tissue contact, 0x02 representing non-tissue conductive medium contact, and 0x00 representing floating or ineffective contact.

[0078] For example, continuing the example process described above, the contact state discrimination module reads the dielectric absorption quantization parameter generated by the biological tissue contact scenario from the data register, the specific value of which is 0.487.

[0079] Simultaneously, the module loads a preset first high-order threshold of 0.40 and a second low-order threshold of 0.10 from the configuration memory. First, the module performs a first comparison, comparing the dielectric absorption quantization parameter 0.487 with the first high-order threshold 0.40. Since 0.487 is greater than 0.40, the condition is met, and the system determines the current contact state as effective tissue contact. Subsequently, the contact state discrimination module generates a contact state classification result representing effective tissue contact, i.e., a hexadecimal code 0x01, and updates it to the system status register. The human-machine interface unit detects the change in this register value and then illuminates an indicator light on the display screen indicating "tissue contact achieved." In contrast, if the device contacts saline solution in the aforementioned steps, the generated dielectric absorption quantization parameter might be 0.05. In this case, since 0.05 is not greater than 0.40, the first comparison fails; a second comparison is then performed. Since 0.05 is lower than the second low-order threshold 0.10, the second comparison succeeds, and the system determines it as non-tissue conductive medium contact, generating the corresponding classification result code 0x02.

[0080] The control logic module is used to generate an energy output enable signal when it receives the operator's main output command and simultaneously confirms that the contact status classification result is effective tissue contact.

[0081] Specifically, this system also includes a main control logic module, which acts as the final decision-maker for energy output. It receives main output commands from the operator, such as foot switch signals, and monitors the contact state classification results generated by the contact state classification module in real time. This logic module contains an AND gate: it only generates and outputs a high-level energy output enable signal to the energy output modulation module when the main output command is valid and the contact state classification result explicitly identifies valid tissue contact. In any other situation, such as contact with conductive liquids, instrument suspension, or no operator command, the enable signal remains low, thus physically locking the energy output channel.

[0082] The energy output modulation module is used to perform analog modulation on the high-frequency surgical energy output stage using analog control voltage when receiving the main output command.

[0083] In a preferred embodiment, analog modulation of the high-frequency surgical energy output stage includes: directly coupling an analog control voltage to the gain control terminal of the high-frequency surgical energy output power stage as a drive bias voltage for its internal power amplification elements.

[0084] The amplitude of the analog control voltage is positively correlated with the conduction level of the power amplification element, and thus positively correlated with the magnitude of the final output therapeutic energy.

[0085] In a further preferred embodiment, analog modulation of the high-frequency surgical energy output stage further includes: utilizing the inherent turn-on threshold voltage of the power amplification element to allow the energy channel to open only when the amplitude of the analog control voltage exceeds the turn-on threshold voltage.

[0086] Upon receiving the energy output enable signal, the power amplifier element is applied with the real-time amplitude of the analog control voltage to continuously and proportionally modulate the magnitude of the therapeutic energy output to the surgical instruments.

[0087] Specifically, after generating the analog control voltage, this voltage signal is used to perform analog modulation on the high-frequency surgical energy output stage. The core of this step lies in a power modulation circuit, which acts as the interface between the analog control domain and the radio frequency power output domain.

[0088] First, the analog control voltage is sent to the power modulation circuit. A key function of this circuit is to linearly convert the analog voltage amplitude into the duty cycle of a high-frequency pulse width modulation (PWM) signal. That is, the higher the analog control voltage, the wider the pulse width of the generated PWM signal and the larger the duty cycle. In this embodiment, the high-frequency surgical energy output stage is a Class D or Class E power amplifier with a power MOSFET as the core switching element. This power MOSFET acts as a voltage-controlled device, and its on / off state is controlled by the voltage signal applied to its gate.

[0089] Secondly, to achieve hardware-level safety latch-up for energy output, the design of this invention includes a separate hardware comparator circuit before the driving power MOSFET, for example, a circuit consisting of a voltage comparator and a reference voltage source. This circuit sets a system-level turn-on threshold voltage. For example, 150mV. Only when the analog control voltage... The comparator circuit output flips only when the amplitude exceeds the threshold voltage, allowing subsequent PWM signal generation and gate drive of the power MOSFET. Conversely, if the control voltage is below this threshold, the signal path driving the power MOSFET is physically blocked regardless of whether the operator issues a command, ensuring zero energy output. This utilizes the circuit's analog characteristics to construct a reliable hardware "intelligent gating".

[0090] It should be emphasized that the threshold voltage here is a logical threshold actively set at the system design level in this invention to achieve safety interlocking. It is a different concept from the gate-source turn-on voltage inherent in the power MOSFET device itself.

[0091] Finally, when the system receives a main output command from the operator (e.g., pressing the foot pedal), the high-frequency oscillation source is enabled. However, the final amount of therapeutic energy output to the surgical instruments is determined in real time by the duty cycle of the aforementioned PWM signal. Since the analog control voltage is directly linked to the PWM duty cycle, and the PWM duty cycle directly determines the output power of the Class D / Class E amplifier, instantaneous, proportional, and continuous adaptive adjustment of the output energy is achieved. The response time of the entire modulation process is limited only by the physical speed of the analog electronic components (typically in the nanosecond to microsecond range), requiring no software intervention, thus achieving efficient and safe closed-loop energy control.

[0092] The final therapeutic energy output to the surgical instruments With analog control voltage The relationship between them can be described by the following piecewise function.

[0093] in, It is the average power of the output healing energy, measured in watts. It is the real-time amplitude of the analog control voltage. It is the threshold voltage for activation. This is a power gain conversion factor, measured in W / V. This factor is determined by the power stage's design parameters, such as supply voltage and load impedance, and typically ranges from 50 W / V to 500 W / V. For example, setting it to W / V... This formula clearly shows that when the analog control voltage is below the threshold voltage, the output power is always zero, regardless of whether the operator issues a command. When the voltage exceeds the threshold, the output power is proportional to the excess voltage.

[0094] For example, following the example scenario described above, and setting the turn-on threshold voltage of the power stage MOSFET. 150mV, power gain conversion factor First, the system's main control logic module receives the main output command from the operator pressing the foot pedal. Simultaneously, it checks the contact status classification and confirms effective tissue contact. Since both conditions are met, the main control logic module immediately generates an energy output enable signal and sends it to the energy output modulation module. Upon receiving this enable signal, the energy output modulation module is activated and applies a real-time generated 207mV analog control voltage to the gate of the power MOSFET, ultimately outputting 22.8W of therapeutic energy. The calculation formula is: In contrast, in the scenario involving contact with saline solution, although the operator stepped on the foot pedal, the main control logic module did not generate an enable signal because the contact status was classified as non-tissue conductive medium contact. The energy output channel remained closed, and the output power was 0W. This process, through direct hardware modulation, achieved adaptive energy output to tissues and automatic lockout of energy output to non-target media.

[0095] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the concept of the invention or exceed the scope defined by the present invention, and all such modifications and additions should fall within the protection scope of the present invention.

Claims

1. A high-frequency surgical instrument and tissue intelligent contact identification system, characterized in that, include: The diagnostic pulse generation module is used to generate and apply an asymmetric biphasic diagnostic pulse sequence to the tip of the surgical instrument to establish a polarized electric field at the contact interface for dielectric property detection. The signal acquisition module is used to receive electrical signals from the tip of the surgical instrument. Within the measurement dead phase of the diagnostic pulse sequence, it acquires the transient residual voltage signal formed by the attenuation of the charge at the contact interface and splits the signal into two outputs: one is a digitized transient residual voltage signal, and the other is an undigitized analog transient residual voltage signal. The parameter calculation module is used to receive transient residual voltage signals and calculate and quantize dielectric absorption quantization parameters that characterize the dielectric absorption capability of the target material based on the signals. The analog control voltage generation module is used to receive the analog transient residual voltage signal and generate the analog control voltage according to the amplitude of the signal at a preset time point. The contact state classification module is used to receive dielectric absorption quantization parameters and classify the contact state according to the comparison result of the parameters with a preset threshold, so as to generate contact state classification results for human-computer interaction display. The contact state includes effective tissue contact and non-tissue conductive medium contact. The control logic module is used to generate an energy output enable signal when it receives the operator's main output command and simultaneously confirms that the contact status classification result is effective tissue contact. The energy output modulation module is used to perform analog modulation on the high-frequency surgical energy output stage using analog control voltage when an energy output enable signal is received.

2. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 1, characterized in that, Asymmetric biphasic diagnostic pulse sequence is generated and applied to the tip of the surgical instrument to establish a polarized electric field at the contact interface for dielectric property detection, including: The pulse generation unit is activated to output an asymmetric biphasic diagnostic pulse sequence to the electrodes of the high-frequency surgical instrument. Each cycle of this sequence consists of a positive charging phase and a subsequent measurement dead zone phase. Control the voltage amplitude of the positive charging phase to keep it below the preset depolarization threshold of biological tissue cell membranes; By applying an asymmetric biphasic diagnostic pulse sequence to the tip of a surgical instrument, a transient polarized electric field is established between the instrument tip and the target material it contacts.

3. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 2, characterized in that, Acquiring the transient residual voltage signal formed by the decay of charge at the contact interface, including: After the positive charging phase ends, the signal buffer circuit connected in parallel with the surgical instrument electrode is activated during the measurement dead phase. Using a signal buffer circuit, the voltage decay curve caused by the natural release of the charge stored at the interface is captured in real time and input to a signal distribution node; The first output of the signal distribution node is connected to an analog-to-digital converter to generate a digital transient residual voltage signal containing time-domain information of the complete attenuation process. The second output of the signal distribution node is transmitted directly as an undigitized analog transient residual voltage signal.

4. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 1, characterized in that, Calculate and quantify dielectric absorption quantization parameters characterizing the dielectric absorption capability of the target material, including: The transient residual voltage signal is analyzed, and the initial voltage value at the start of the measurement dead zone phase and the terminal voltage value at the end of the preset time window are extracted respectively. The initial voltage holding rate is obtained by calculating the ratio of the terminal voltage value to the initial voltage value.

5. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 4, characterized in that, The calculation and quantification of dielectric absorption quantization parameters characterizing the dielectric absorption capability of the target material also includes: Obtain the preset normalized calibration parameters; The initial voltage retention rate is normalized using normalized calibration parameters to generate standardized dielectric absorption quantization parameters.

6. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 1, characterized in that, Generate analog control voltage, including: The simulated transient residual voltage signal is input to a sample-and-hold circuit that is synchronously triggered with an asymmetric biphase diagnostic pulse sequence; The sample-and-hold circuit samples the amplitude of the analog transient residual voltage signal at a preset sampling delay time point within the measurement dead zone phase, outputs a holding DC voltage proportional to the sampling amplitude, and uses this holding DC voltage as the analog control voltage.

7. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 1, characterized in that, The system receives dielectric absorption quantization parameters and classifies the contact state based on a comparison between these parameters and a preset threshold, generating a contact state classification result for human-computer interaction display, including: The dielectric absorption quantization parameter is compared with a preset material property threshold, which includes a first high threshold for defining biological tissue and a second low threshold for defining conductive liquid. If the dielectric absorption quantization parameter is greater than the first high-order threshold, the current contact state is determined to be an effective tissue contact. If the dielectric absorption quantization parameter is lower than the second lowest threshold, it is determined to be a non-organic conductive dielectric contact.

8. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 7, characterized in that, The system receives dielectric absorption quantization parameters and classifies the contact state based on a comparison between these parameters and a preset threshold to generate a contact state classification result for human-computer interaction display. The system also includes: Based on the determined state of effective tissue contact or non-tissue conductive medium contact, a corresponding digital code is generated. The output identifies the contact status classification results, which are used by the human-computer interaction unit for status display or log recording.

9. The high-frequency surgical instrument and tissue intelligent contact identification system according to claim 1, characterized in that, Analog modulation of the high-frequency surgical energy output stage includes: The analog control voltage is directly coupled to the gain control terminal of the high-frequency surgical energy output power stage as the driving bias voltage for its internal power amplification components. The amplitude of the analog control voltage is positively correlated with the conduction level of the power amplification element, and thus positively correlated with the magnitude of the final output therapeutic energy.

10. A high-frequency surgical instrument and tissue intelligent contact identification system according to claim 9, characterized in that, Analog modulation of the high-frequency surgical energy output stage also includes: By utilizing the inherent turn-on threshold voltage of the power amplifier components, the energy channel is allowed to open only when the amplitude of the analog control voltage exceeds the turn-on threshold voltage; Upon receiving the energy output enable signal, the power amplifier element is applied with the real-time amplitude of the analog control voltage to continuously and proportionally modulate the magnitude of the therapeutic energy output to the surgical instruments.

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