A digestive tract pulsed electric field ablation device and system
By utilizing impedance differences and real-time monitoring technology in the duodenal ablation device to dynamically adjust pulse parameters, the problems of insufficient ablation depth control and feedback were solved, achieving precise ablation of the duodenal mucosa and improving safety and efficacy consistency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SUZHOU YUANKE MEDICAL EQUIPMENT CO LTD
- Filing Date
- 2026-06-01
- Publication Date
- 2026-06-26
AI Technical Summary
Existing pulsed electric field ablation technology has limitations in its application to the duodenum, including insufficient precision in controlling ablation depth and a lack of real-time, accurate tissue-level feedback. This makes it difficult to adapt to individual differences, resulting in a trade-off between safety and effectiveness and an inability to achieve precise mucosal layer ablation.
By setting up an electrode array membrane and a detection module in the ablation device, the ablation depth is monitored in real time by taking advantage of the difference in impedance characteristics between the duodenal mucosa and submucosa/muscular layer at different frequencies. The pulse parameters are dynamically adjusted, and combined with the phase angle mutation parameter and cell membrane breakdown index, the ablation endpoint can be accurately determined.
It achieves targeted destruction of the duodenal mucosa, avoids damage to deep tissues, improves the safety and efficacy consistency of metabolic disease treatment, adapts to the differences in intestinal wall thickness among different individuals, and ensures that mucosal cells are fully ablated.
Smart Images
Figure CN122272151A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of pulse generation and medical device technology, and in particular to a digestive tract pulse electric field ablation device and system. Background Technology
[0002] In recent years, duodenal mucosal remodeling (DMR) has been shown to effectively control type 2 diabetes and obesity by ablating pathological duodenal mucosa and intervening in intestinal endocrine signaling pathways. Clinical studies have preliminarily confirmed its effectiveness and safety in improving glycemic control and weight loss.
[0003] Currently, the mainstream ablation techniques in this field rely on thermodynamic principles, such as hot water balloon ablation. This technique causes tissue coagulation and necrosis through heat conduction. However, thermal ablation has some inherent drawbacks. First, heat conduction in tissue is diffuse and cannot be precisely controlled, easily causing thermal damage to non-targeted deep tissues (such as the muscle layer), increasing the risk of serious complications such as intestinal perforation and stenosis. Second, the thermal effect indiscriminately destroys the extracellular matrix, potentially affecting mucosal repair and regeneration, and possibly causing excessive scarring.
[0004] Pulsed electric field (PEF) ablation, as a non-thermal ablation technique, holds great promise for the treatment of metabolic diseases due to its ability to selectively destroy cell membranes while preserving the extracellular matrix (ECM). PEF ablation selectively induces apoptosis or necrosis by instantaneously creating irreversible nanoscale electroporation pores on the cell membrane, while maximally preserving the integrity and structure of the ECM. This tissue-selective characteristic allows PEF to effectively ablate the mucosa while protecting the basic scaffold of the intestine, theoretically significantly reducing the risk of perforation and stenosis, and promoting rapid and orderly regeneration of healthy mucosa. Therefore, it shows great application potential in duodenal mucosal remodeling.
[0005] However, when applying PEF technology to the duodenum, a special anatomical location, it also faces some technical bottlenecks that are difficult to overcome with existing technologies, which restrict its efficacy and safety.
[0006] First, existing pulsed electric field ablation (PEF) techniques suffer from insufficient precision in controlling ablation depth, and their adaptability is also challenged due to individual differences. The duodenal wall is not thin, typically only about 2-3 mm, and the thickness of the mucosa, submucosa, and muscularis propria varies significantly between individuals and between different intestinal segments. Existing PEF ablation devices generally operate using preset, fixed electrical pulse parameters (such as voltage, pulse width, and pulse count). This one-size-fits-all approach cannot adapt to individual differences. If the pulse energy is too strong or the action time is too long, the electric field can easily penetrate the submucosa, damaging or even destroying the muscularis propria, leading to irreversible and serious complications such as intestinal motility disorders, fibrosis, and even perforation. Conversely, if the energy is insufficient, it cannot ensure that the mucosa is fully and uniformly ablated, directly affecting the intervention effect on endocrine signaling pathways, resulting in poor blood sugar lowering and weight loss efficacy. Therefore, how to precisely destroy the target mucosa layer and stop at its lower boundary is one of the challenges facing PEF duodenal ablation.
[0007] Secondly, the lack of a real-time, precise tissue-level feedback mechanism means the ablation process is often performed blindly. A prerequisite for precise control is the system's ability to sense in real-time which tissue layer the electric field is acting on and what changes are occurring within that tissue. Existing technologies, such as those disclosed in Chinese patent applications CN119138872A and CN103379873B, typically use a single impedance monitoring signal to assess ablation effectiveness and damage. However, the duodenal mucosa (rich in epithelial cells and glands) and submucosa (rich in blood vessels, nerves, and connective tissue) differ significantly in microstructure and composition, resulting in complex dielectric properties (conductivity, permittivity) in response to pulsed electric fields. During ablation, tissue impedance dynamically changes as cell electroporation occurs, but a single impedance measurement cannot effectively decouple and distinguish whether this change originates from effective damage to the mucosa or has already begun to affect the submucosa. The system cannot accurately determine in real time whether the ablation front has reached the mucosa-submucosal junction during the ablation process, nor can it provide early warning of the impending risk of muscle layer damage. This prevents the operator from intervening at critical moments, and the entire ablation process lacks closed-loop control based on tissue condition.
[0008] In summary, existing duodenal ablation techniques based on pulsed electric fields are limited by fixed ablation parameters and a single, non-specific feedback signal. This makes it difficult to solve the problem of precise ablation caused by the thin duodenal wall and large individual differences. It is difficult to balance safety and effectiveness (precision), which limits the full realization of the advantages of PEF technology.
[0009] The disclosure of the above background information is only for the purpose of assisting in understanding the concept and technical solution of this application, and does not necessarily provide technical instruction. Summary of the Invention
[0010] The purpose of this invention is to provide a digestive tract pulsed electric field ablation device and system. By utilizing the difference in impedance characteristics between the duodenal mucosa and submucosa / muscular layer at different frequencies, a baseline assessment of mucosal thickness can be achieved before ablation, and the perforation depth can be monitored in real time during the ablation pulse interval. This allows for dynamic adjustment of pulse parameters and precise determination of the ablation endpoint, enabling safe, moderate, and customized ablation for metabolic diseases.
[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A digestive tract pulsed electric field ablation device, comprising: An electrode array film having multiple pairs of electrodes consisting of a first electrode and an adjacent second electrode disposed thereon; A pulse generator has a pulse signal output terminal, which is coupled to the electrode pair to generate an ablation current on the electrode pair when the pulse generator outputs a sequence of pulse waves. The detection module has a detection signal output terminal, which is also coupled to the electrode pair. It is used to generate a detection current on the electrode pair to obtain an echo signal when a detection excitation signal is output during a pulse gap. The detection excitation signal covers at least two frequency points within a preset frequency range. The control unit is electrically connected to the pulse generator and the detection module respectively. The control unit is configured to output a first control signal to the pulse generator to cause the pulse generator to output the sequence pulse wave, and the control unit is configured to output a second control signal to the detection module to cause the detection module to output the detection excitation signal. The control unit is also configured to receive the echo signal and control the pulse generator according to the echo signal.
[0012] Furthermore, following any one or a combination of the aforementioned technical solutions, the control unit is configured to control the pulse generator based on the echo signal in the following manner: Based on the echo signal, the frequency point at which the impedance phase angle is most affected by changes in cell membrane capacitance is determined as the characteristic phase frequency. ,collection The corresponding phase angle is The characteristic phase frequency and phase angle as a function of time are determined based on the time-series echo signal. t function of change ; calculate The first-order time derivative is used to obtain the phase angle abrupt change parameter. : ; like , If the preset phase angle abrupt change safety threshold is met, it is determined that the edge of the electric field has broken through the physical boundary of the mucosa layer and entered the submucosal layer, and the control unit controls the pulse generator to stop outputting the sequence pulse wave.
[0013] Furthermore, following any one or a combination of the aforementioned technical solutions, the control unit is configured to control the pulse generator based on the echo signal in the following manner: Based on the echo signal, extract the preset first frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the low-frequency impedance amplitude variation function ; Based on the echo signal, extract the preset second frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the high-frequency impedance amplitude variation function ; The cell membrane breakdown index is calculated using the following formula: ; like and Then the control unit controls the pulse generator to output a sequence of pulse waves.
[0014] Furthermore, following any one or a combination of the aforementioned technical solutions, the control unit is configured to control the pulse generator based on the echo signal in the following manner: Based on the echo signal, extract the preset first frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the low-frequency impedance amplitude variation function ; Based on the echo signal, extract the preset second frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the high-frequency impedance amplitude variation function ; The cell membrane breakdown index is calculated using the following formula: ; If multiple consecutive detection cycles meet the following: and Then the control unit controls the pulse generator to stop outputting the sequence pulse wave.
[0015] Furthermore, based on any one or a combination of the aforementioned technical solutions, The value range is from 1.05 to 1.30.
[0016] Furthermore, based on any one or a combination of the aforementioned technical solutions, The value is 1.15.
[0017] Furthermore, following any one or a combination of the aforementioned technical solutions, the first frequency reference point Within the range of 10kHz to 50kHz; and / or, Second frequency reference point Within the range of 500kHz to 1MHz; and / or, The characteristic phase frequency Within the 80kHz to 150kHz range, this characteristic phase frequency can also dynamically extend to 50kHz to 200kHz in the duodenum of certain pathological conditions or extremely obese patients.
[0018] Furthermore, following any one or a combination of the aforementioned technical solutions, the pulse gap is on the order of milliseconds; and / or, The detection current is greater than or equal to 100 μA and less than or equal to 1.5 mA; and / or, The detection excitation signal is a sinusoidal signal; and / or, The sequence pulse wave includes multiple nanosecond-level pulse trains, each consisting of multiple nanosecond pulse pairs. Each nanosecond pulse pair consists of alternating positive and negative pulses. The time interval between two adjacent nanosecond-level pulse trains is configured as the pulse gap; and / or, Within each frequency sweep cycle, the frequency of the detection excitation signal continuously increases from a first frequency to a second frequency, from low to high; the first frequency is in the range of 5 kHz to 20 kHz; the second frequency is in the range of 800 kHz to 1.5 MHz; and / or, The detection excitation signal is a swept-frequency excitation signal with a frequency varying from low to high; and / or, The detection excitation signal is a periodic signal, and within each period, the detection excitation signal covers at least two frequency points within a preset frequency range.
[0019] Furthermore, in accordance with any or a combination of the aforementioned technical solutions, a high-voltage relay is also included, wherein the pulse signal output terminal of the pulse generator is coupled to the electrode pair via the high-voltage relay, and the detection signal output terminal of the detection module is also coupled to the electrode pair via the high-voltage relay; The high-voltage relay has a first working mode and a second working mode. When the high-voltage relay is in the first working mode, the high-voltage relay connects the pulse generator to the electrode pair and disconnects the detection module from the electrode. The pulse generator outputs a sequence of pulse waves to the electrode pair. When the high-voltage relay is in the second operating mode, the high-voltage relay disconnects the pulse generator from the electrode pair and connects the detection module to the electrode pair, and the detection module outputs a detection excitation signal to the electrode pair.
[0020] Furthermore, based on any or a combination of the aforementioned technical solutions, the detection module includes a digital frequency synthesizer, a wideband voltage-controlled current source, and a sampling module, wherein the digital frequency synthesizer generates a sinusoidal voltage signal, and the wideband voltage-controlled current source converts the sinusoidal voltage signal into an AC sweep frequency current to inject into the electrode pair; The sampling module is configured to acquire the echo signal and transmit it to the control unit.
[0021] According to another aspect of the present invention, the present invention provides a digestive tract pulsed electric field ablation system, which includes a digestive tract pulsed electric field ablation device as described in any one or a combination of the above technical solutions, and further includes: a gastroscopy device, the gastroscopy device including a gastroscopy body, the gastroscopy body being provided with a surgical instrument channel, and the electrode array membrane being disposed within the surgical instrument channel.
[0022] The beneficial effects of the technical solution provided by this invention are as follows: a. The pulsed electric field ablation device provided by the present invention can strictly limit ablation to the duodenal mucosa layer by using the detection excitation signal output between pulses and the multi-frequency impedance spectrum of its echo signal to identify tissue layers in real time. It can achieve targeted destruction of the mucosa while effectively protecting the extracellular matrix and deep muscle layer, which can completely solve the problem of delayed duodenal stenosis that is easily caused by traditional ablation and greatly improve the safety of metabolic disease treatment. b. This invention evaluates the ablation status by combining the phase angle mutation parameter obtained from a wide spectrum from low frequency to high frequency and the cell membrane breakdown index. It can overcome anatomical differences, ensure the consistency of therapeutic effects, and achieve adaptive energy output for individual differences in intestinal wall thickness in obese or diabetic patients. This ensures that the mucosal cells of each patient can be fully and without excessive ablation, thus ensuring the clinical effectiveness of remodeling endocrine pathways. c. This invention utilizes the extremely high off-state impedance and physical isolation characteristics of high-voltage relays to block high voltage from entering the detection module during pulse ablation. By utilizing the high sensitivity of the detection module and its microsecond-level response characteristics, transient high-frequency detection of the pulse gap is achieved in hardware through components such as precision current transformers. This ensures that the pulse electric field ablation device can make a millisecond-level or even microsecond-level cutoff response before causing deep damage. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 A schematic diagram of a digestive tract pulsed electric field ablation device provided as an exemplary embodiment of the present invention; Figure 2 A control flowchart of a digestive tract pulsed electric field ablation device provided as an exemplary embodiment of the present invention; Figure 3 A schematic diagram of the composition structure of a first type of sequential pulse wave provided as an exemplary embodiment of the present invention; Figure 4 A schematic diagram of the composition structure of a second type of sequential pulse wave provided as an exemplary embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of an electrode array film provided for an exemplary embodiment of the present invention.
[0025] The components are: 1. conduit; 2. support body; 3. electrode array membrane; 4. first electrode; 5. second electrode; 6. electrode pair. Detailed Implementation
[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.
[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, apparatus, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.
[0028] The duodenal mucosa is composed of dense columnar epithelial cells and glands, with high cell density and significant cell membrane capacitance effect; while the submucosa is mainly composed of loose connective tissue, blood vessels and lymphatic vessels, with extremely low cell density and high extracellular fluid (rich in electrolytes).
[0029] During pulsed electric field ablation, as the cell membranes of the mucosal layer are continuously broken down (irreversible electroporation occurs), the overall conductivity of the tissue increases and the capacitance decreases. When the edge of the ablation field just touches the submucosa, the impedance spectrum characteristics will undergo a rapid nonlinear "collapse" or "abrupt change" because the underlying tissue itself lacks a dense cell membrane barrier and has excellent conductivity.
[0030] To address the technical challenge of ensuring safety, effectiveness, and precision for different individuals due to fixed ablation parameters and a single, non-specific feedback signal in the application of PEF technology in duodenal ablation, this application provides a digestive tract pulsed electric field ablation device and system. Utilizing the difference in impedance characteristics between the duodenal mucosa and submucosa / muscular layer at different frequencies, baseline assessment of mucosal thickness is achieved before ablation, and perforation depth is monitored in real-time during the ablation pulse interval. This allows for dynamic adjustment of pulse parameters and precise determination of the ablation endpoint, enabling safe, appropriate, and customized ablation for metabolic diseases.
[0031] In one embodiment of the present invention, a digestive tract pulsed electric field ablation device is provided, see [link to relevant documentation]. Figure 1 and Figure 2 It includes a slender conduit, a support, an electrode array membrane, a pulse generator, a detection module, a control unit, and a high-voltage relay.
[0032] See Figure 5The support 2 is located at the distal end of the conduit 1, and has a contracted working state and an expanded working state. Before the distal end of the conduit 1 reaches the target position, the support 2 is configured in the contracted working state to facilitate the movement of the conduit and the support and reduce injury to the human body. When the distal end of the conduit 1 reaches the target position, the support 2 is configured in the expanded working state to control the device to release a pulsed electric field at the target position.
[0033] The electrode array membrane 3 is arranged on the support 2, and multiple pairs of electrodes, each consisting of a first electrode and an adjacent second electrode, are disposed thereon. When the support 2 is in an expanded working state, the electrode array membrane 3 is spread out on the support 2; when the support 2 is in a contracted working state, the electrode array membrane 3 is contracted on the support 2, and multiple pairs of electrodes 6, each consisting of a first electrode 4 and an adjacent second electrode 5, are disposed on the electrode array membrane 3.
[0034] The pulse generator has a pulse signal output terminal, which is coupled to the electrode pair to generate an ablation current on the electrode pair when the pulse generator outputs a sequence of pulse waves. The pulse generator preferably employs an H-bridge topology to output a steep high-voltage pulse.
[0035] The detection module has a detection signal output terminal, which is also coupled to the electrode pair. It is used to generate a detection current on the electrode pair to obtain an echo signal when a detection excitation signal is output during a pulse gap. The detection excitation signal covers at least two frequency points within a preset frequency range.
[0036] The control unit is electrically connected to the pulse generator and the detection module respectively. The control unit is configured to output a first control signal to the pulse generator to make the pulse generator output the sequence pulse wave. The control unit is configured to output a second control signal to the detection module to make the detection module output the detection excitation signal. The control unit is also configured to receive the echo signal and control the pulse generator according to the echo signal.
[0037] The pulse signal output terminal of the pulse generator is coupled to the electrode pair through the high-voltage relay, and the detection signal output terminal of the detection module is also coupled to the electrode pair through the high-voltage relay. The high-voltage relay is used to both isolate high-voltage ablation and low-voltage broadband measurement.
[0038] The high-voltage relay has a first operating mode and a second operating mode. When the high-voltage relay is in the first operating mode, it switches to the high-voltage ablation position. The high-voltage relay connects the pulse generator to the electrode pair and disconnects the detection module from the electrode pair. The pulse generator outputs a sequence of pulse waves to the electrode pair. When the H-bridge outputs a high-voltage pulse group for ablation, the extremely high off-state impedance and physical isolation characteristics of the high-voltage relay completely block the high voltage from entering the measurement end, i.e., the detection module.
[0039] When the high-voltage relay is in the second working mode, the high-voltage relay switches to the impedance measurement position. The high-voltage relay disconnects the pulse generator from the electrode pair and connects / connects the detection module to the electrode pair. The detection module outputs a detection excitation signal to the electrode pair through the high-voltage relay.
[0040] The detection module is configured as a broadband impedance spectrum detection module, which includes a digital frequency synthesizer (DDS) and a broadband voltage-controlled current source sampling module. Under the control of the control unit, the detection module generates a sinusoidal signal and can rapidly inject a broadband (e.g., 10kHz-5MHz) weak detection current during the pulse firing interval to obtain the echo signal.
[0041] Specifically, the digital frequency synthesizer is configured as a high-precision sweep frequency source to generate a sine wave signal ranging from 10 kHz to 5 MHz. The wideband voltage-controlled current source employs an improved Howland current pump constructed with a wideband operational amplifier to smoothly inject a weak current signal of 100 μA to 1 mA to convert the sinusoidal voltage signal into a weak AC sweep frequency current, i.e., the detection excitation signal, for injection into the electrode pair. Preferably, the detection excitation signal is a sweep frequency excitation signal. The sweep frequency excitation signal is a sinusoidal signal, and the detection current is greater than or equal to 100 μA and less than or equal to 1.5 mA. Within each sweep frequency cycle, the frequency of the sweep frequency excitation signal increases from a first frequency to a second frequency, from low to high; the first frequency is in the range of 5 kHz to 20 kHz; and the second frequency is in the range of 800 kHz to 1.5 MHz.
[0042] The sampling module is configured to acquire the echo signal and transmit it to the control unit. Preferably, the sampling module includes an electrically connected high-frequency current transformer and a differential amplifier for synchronously acquiring current and voltage echo signals flowing through the tissue.
[0043] The pulse gap is the time interval between two adjacent pulses in the sequence of pulse waves. Preferably, the time interval between two adjacent pulses is configured to be on the order of microseconds or milliseconds.
[0044] In one specific embodiment, such as Figure 3As shown, the pulse generator is configured to generate bipolar nanosecond / microsecond pulse electrical signals. The sequence pulse wave includes multiple nanosecond-level pulse trains, each consisting of multiple nanosecond pulse pairs. Each nanosecond pulse pair consists of alternating positive and negative pulses. The time interval between two adjacent nanosecond-level pulse trains is... Figure 3 The pulse train interval shown is configured as the pulse gap. More preferably, the pulse width is greater than or equal to 0.1 μs and less than or equal to 100 μs; the output voltage is greater than or equal to 500V and less than or equal to 20kV; positive and negative pulses are generated alternately, with a 0-level time interval between the positive and negative pulses, the time interval being greater than or equal to 0.1 μs and less than or equal to 1000 μs; one positive pulse and one negative pulse constitute a pulse pair, with a 0-level pulse interval between the pulse pairs, the pulse interval being greater than or equal to 0.1 μs and less than or equal to 5000 ms.
[0045] In another specific embodiment, such as Figure 4 As shown, the sequence pulse wave includes multiple nanosecond-level pulse trains, each composed of multiple nanosecond pulse pairs, where each nanosecond pulse pair consists of alternating positive and negative pulses. The pulse generator outputs the sequence pulse wave over time periods ranging from the first time period to the Nth time period, where the time interval between two adjacent time periods is... Figure 4 The sequence of pulse wave intervals shown is configured as the pulse gap.
[0046] It should be noted that, Figure 3 pulse train interval and Figure 4 The sequence pulse wave interval in the example is a pulse interval and is not intended to limit the scope of protection of this application. The sequence pulse wave can also be set in other ways, and the pulse interval only needs to meet the following conditions: (1) it is the time interval between two adjacent pulses; (2) it is not less than the duration required by the sweep frequency excitation signal.
[0047] In specific applications, the digestive tract pulsed electric field ablation device proposed in this application includes the following usage periods.
[0048] (1) Pulse ablation period T1: The high-voltage relay switches to the high-voltage ablation position, and the control unit drives the pulse generator (H bridge) to issue a series of high-voltage pulses.
[0049] (2) Residual high voltage discharge period T2: When the pulse train / group ends, the active discharge circuit is started to quickly eliminate residual charge on the tissue polarization voltage and cable distributed capacitance, ensuring that the terminal voltage drops below the safe threshold.
[0050] (3) Impedance detection period T3: The high-voltage relay switches to the impedance measurement position, and the DDS starts frequency sweeping, sequentially outputting excitation signals from low frequency (e.g., 10kHz), medium frequency (e.g., 100kHz) to high frequency (e.g., 5MHz). The acquisition module performs multi-cycle average sampling to calculate the impedance spectrum characteristic index after the current pulse group action, including characteristic impedance and phase angle.
[0051] (4) Data processing and logic determination period T4: The control unit determines whether the electroporation has approached the submucosa of the duodenum based on the calculated impedance spectrum characteristic index. If the boundary warning is not triggered and the ablation endpoint is not reached, the next round of pulse burst firing will begin (return to T1).
[0052] The device acquires the echo signal at high speed via an analog-to-digital converter (ADC) during pulse gaps (preferably on the millisecond level) and extracts impedance data at the following key characteristic frequencies: The low-frequency reference point is the first frequency reference point. ): Set in the 10kHz to 50kHz range, this frequency band makes it difficult for current to penetrate the cell membrane, and the impedance amplitude is... It mainly reflects the conductivity of extracellular fluid and transmembrane pores formed by electroporation; The high-frequency reference point is the second frequency reference point. ): Set in the 500kHz to 1MHz range, this frequency band allows current to directly penetrate the cell membrane, with impedance amplitude It reflects the overall dielectric state inside and outside the cell; Characteristic phase frequency ( The frequency is set at the point where the impedance phase angle is most sensitive to changes in cell membrane capacitance, typically around 100kHz, within the range of 80kHz to 150kHz. The phase angle at this point is then collected. .
[0053] Based on the aforementioned low-frequency reference point, high-frequency reference point, characteristic phase frequency, and phase angle, the following characteristic indices are further calculated.
[0054] Characteristic Index 1: Cell Membrane Breakdown Index.
[0055] Based on the echo signal, extract the preset first frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the low-frequency impedance amplitude variation function .
[0056] Based on the echo signal, extract the preset second frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the high-frequency impedance amplitude variation function .
[0057] The cell membrane breakdown index is calculated using the following formula: .
[0058] The cell membrane breakdown index is used to assess the completeness of irreversible electroporation of the current mucosal layer cells, wherein, express t The impedance amplitude corresponding to the low-frequency reference point at any given moment; express t The impedance amplitude corresponding to the high-frequency reference point at any given time.
[0059] In the initial state, when the tissue is intact, the low-frequency impedance is much greater than the high-frequency impedance, and MBI(t) is usually between 2 and 3.
[0060] During the ablation process, as electroporation intensifies, the low-frequency impedance drops sharply, and MBI(t) gradually approaches 1.
[0061] Feature index two: Derivative of organizational hierarchy transition.
[0062] This characteristic index is used to capture the abrupt change in dielectric properties as an electric field penetrates the high-density cell layer (mucosal layer) and enters the low-density cell layer (submucosal layer). Because the submucosal layer lacks cell membrane capacitance, once the electric field touches this layer, the phase angle at the characteristic frequency drops precipitously.
[0063] This application captures this instant by calculating the first-order time derivative of the phase angle, i.e., the phase angle abruptness parameter. Based on the echo signal, the frequency point where the impedance phase angle is most affected by changes in cell membrane capacitance is determined as the characteristic phase frequency. ,collection The corresponding phase angle is The characteristic phase frequency and phase angle as a function of time are determined based on the time-series echo signal. t function of change .
[0064] calculate The first-order time derivative is used to obtain the phase angle abrupt change parameter. : ; in, This represents a function that describes the change of phase angle with time t based on the characteristic phase frequency. This represents the characteristic phase frequency.
[0065] During the data processing and logic determination phase, closed-loop determination logic and control execution actions are performed based on the following three conditions.
[0066] Condition 1: Submucosal layer breach warning (emergency transection).
[0067] In any detection period, if , A preset safety threshold for phase angle abrupt change is set. If the phase angle drops drastically beyond the normal electroporation rate, it is immediately determined that the edge of the electric field has broken through the physical boundary of the mucosal layer and entered the submucosa. The control unit triggers the highest priority interrupt, cutting off the high-voltage circuit drive signal of the pulse generator within microseconds, forcibly stopping energy output, thereby absolutely ensuring that the intestinal wall muscle layer is not damaged.
[0068] Condition 2: Ablation is in progress (parameters maintained).
[0069] when and If it is determined that the main ablation area is still within the mucosal layer and has not been completely ablated, then high-voltage pulses continue to be output according to the current parameters; that is, the control unit controls the pulse generator to output a sequence of pulse waves. The preset mucosal ablation target threshold, The value range is from 1.05 to 1.30, preferably. The value is 1.15. This is a preset safety threshold for phase angle mutations.
[0070] Condition 3: Complete ablation of the mucosa (normally stopped).
[0071] If multiple consecutive detection cycles meet the following: and If the local mucosal cells are completely and irreversibly ablated, the control unit will control the pulse generator to stop outputting sequential pulse waves. The control unit will issue a command to stop pulse output, indicating that the current area has been successfully ablated.
[0072] In one embodiment of the present invention, a digestive tract pulsed electric field ablation system is provided, which includes the digestive tract pulsed electric field ablation device as described in any of the above embodiments, and further includes: a gastroscopy device, the gastroscopy device including a gastroscopy body, the gastroscopy body being provided with a surgical instrument channel, and the electrode array membrane being disposed in the surgical instrument channel.
[0073] It should be noted that the above embodiments of the digestive tract pulsed electric field ablation system and the embodiments of the digestive tract pulsed electric field ablation device have the same inventive concept. All contents of the embodiments of the digestive tract pulsed electric field ablation device are incorporated into the embodiments of the digestive tract pulsed electric field ablation system by reference.
[0074] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0075] The above description is only a specific embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
Claims
1. A digestive tract pulsed electric field ablation device, characterized in that, It includes: An electrode array film having multiple pairs of electrodes consisting of a first electrode and an adjacent second electrode disposed thereon; A pulse generator has a pulse signal output terminal, which is coupled to the electrode pair to generate an ablation current on the electrode pair when the pulse generator outputs a sequence of pulse waves. The detection module has a detection signal output terminal, which is also coupled to the electrode pair. It is used to generate a detection current on the electrode pair to obtain an echo signal when a detection excitation signal is output during a pulse gap. The detection excitation signal covers at least two frequency points within a preset frequency range. The control unit is electrically connected to the pulse generator and the detection module respectively. The control unit is configured to output a first control signal to the pulse generator to cause the pulse generator to output the sequence pulse wave, and the control unit is configured to output a second control signal to the detection module to cause the detection module to output the detection excitation signal. The control unit is also configured to receive the echo signal and control the pulse generator according to the echo signal.
2. The digestive tract pulsed electric field ablation device according to claim 1, characterized in that, The control unit is configured to control the pulse generator based on the echo signal in the following manner: Based on the echo signal, the frequency point at which the impedance phase angle is most affected by changes in cell membrane capacitance is determined as the characteristic phase frequency. ,collection The corresponding phase angle is The characteristic phase frequency and phase angle as a function of time are determined based on the time-series echo signal. t function of change ; calculate The first-order time derivative is used to obtain the phase angle abrupt change parameter. : ; like , If the preset phase angle abrupt change safety threshold is met, it is determined that the edge of the electric field has broken through the physical boundary of the mucosa layer and entered the submucosal layer, and the control unit controls the pulse generator to stop outputting the sequence pulse wave.
3. The digestive tract pulsed electric field ablation device according to claim 2, characterized in that, The control unit is configured to control the pulse generator based on the echo signal in the following manner: Based on the echo signal, extract the preset first frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the low-frequency impedance amplitude variation function ; Based on the echo signal, extract the preset second frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the high-frequency impedance amplitude variation function ; The cell membrane breakdown index is calculated using the following formula: ; like and Then the control unit controls the pulse generator to output a sequence of pulse waves.
4. The digestive tract pulsed electric field ablation device according to claim 2, characterized in that, The control unit is configured to control the pulse generator based on the echo signal in the following manner: Based on the echo signal, extract the preset first frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the low-frequency impedance amplitude variation function ; Based on the echo signal, extract the preset second frequency reference points at multiple time points. Corresponding impedance amplitude To obtain the high-frequency impedance amplitude variation function ; The cell membrane breakdown index is calculated using the following formula: ; If multiple consecutive detection cycles meet the following: and Then the control unit controls the pulse generator to stop outputting the sequence pulse wave.
5. The digestive tract pulsed electric field ablation device according to claim 3 or 4, characterized in that, The value range is from 1.05 to 1.
30.
6. The digestive tract pulsed electric field ablation device according to claim 5, characterized in that, The value is 1.
15.
7. The digestive tract pulsed electric field ablation device according to claim 5, characterized in that, First frequency reference point Within the range of 10kHz to 50kHz; and / or, Second frequency reference point Within the range of 500kHz to 1MHz; And / or, The characteristic phase frequency Within the range of 50kHz to 200kHz.
8. The digestive tract pulsed electric field ablation device according to claim 1, characterized in that, The pulse interval is on the order of milliseconds; and / or, The detection current is greater than or equal to 100 μA and less than or equal to 1.5 mA; and / or, The detection excitation signal is a sinusoidal signal; and / or, The sequence pulse wave includes multiple nanosecond-level pulse trains, each nanosecond-level pulse train is composed of multiple nanosecond pulse pairs, each nanosecond pulse pair is composed of alternating positive and negative pulses, and the time interval between two adjacent nanosecond-level pulse trains is configured as the pulse gap. And / or, Within each frequency sweep cycle, the frequency of the detection excitation signal continuously increases from a first frequency to a second frequency, from low to high; the first frequency is in the range of 5 kHz to 20 kHz; the second frequency is in the range of 800 kHz to 1.5 MHz; and / or, The detection excitation signal is a swept-frequency excitation signal with a frequency varying from low to high; and / or, The detection excitation signal is a periodic signal, and within each period, the detection excitation signal covers at least two frequency points within a preset frequency range.
9. The digestive tract pulsed electric field ablation device according to claim 1, characterized in that, It also includes a high-voltage relay, the pulse signal output terminal of the pulse generator is coupled to the electrode pair through the high-voltage relay, and the detection signal output terminal of the detection module is also coupled to the electrode pair through the high-voltage relay; The high-voltage relay has a first working mode and a second working mode. When the high-voltage relay is in the first working mode, the high-voltage relay connects the pulse generator to the electrode pair and disconnects the detection module from the electrode. The pulse generator outputs a sequence of pulse waves to the electrode pair. When the high-voltage relay is in the second operating mode, the high-voltage relay disconnects the pulse generator from the electrode pair and connects the detection module to the electrode pair, and the detection module outputs a detection excitation signal to the electrode pair.
10. The digestive tract pulsed electric field ablation device according to claim 1, characterized in that, The detection module includes a digital frequency synthesizer, a wideband voltage-controlled current source, and a sampling module. The digital frequency synthesizer generates a sinusoidal voltage signal, and the wideband voltage-controlled current source converts the sinusoidal voltage signal into an AC sweep frequency current to be injected into the electrode pair. The sampling module is configured to acquire the echo signal and transmit it to the control unit.
11. A digestive tract pulsed electric field ablation system, characterized in that, It includes the digestive tract pulsed electric field ablation device as described in any one of claims 1 to 10, and further includes: a gastroscopy device, the gastroscopy device including a gastroscopy body, the gastroscopy body being provided with a surgical instrument channel, and the electrode array membrane being disposed within the surgical instrument channel.