Interventional ablation simulation system and method

Abstract

The invention discloses an interventional ablation simulation system and method, the system comprises a dynamic electric heating bionic matrix module, a self-adaptive microfluidic perfusion network module and a circulating power and interface module, the dynamic electric heating bionic matrix module adopts a temperature-sensitive porous hydrogel elastomer, and liquid metal droplets are dispersed and distributed in the dynamic electric heating bionic matrix module; in the initial stage of electromagnetic heating, hydrogel is dehydrated and shrunk to force liquid metal micro-droplets to be fused to form a conductive path to cause impedance reduction, the path is cut off to cause polarization resistance jump when carbonization is caused by continuous heating, and a thermosensitive shape memory polymer valve layer is attached to the inner wall of a pipeline of the self-adaptive microfluidic perfusion network module; when the local temperature reaches a threshold value, phase change contraction is carried out to block flowing of a cooling working medium, the dynamic heat sink effect is stripped, and a touch sensing pipeline containing shear thickening fluid and a probe clamping excitation assembly are combined. According to the invention, pure hardware equivalent simulation of electrical evolution, vascular coagulation closure and tactile feedback in real tissue ablation is realized.

Description

Technical Field

[0001] This invention relates to the field of medical devices and medical simulation technology, specifically to an interventional ablation simulation system and method. Background Technology

[0002] Interventional ablation therapy is a minimally invasive medical treatment that involves inserting an ablation probe into the target lesion tissue and using high-frequency electromagnetic energy such as radiofrequency or microwave to generate localized high temperatures, causing thermal coagulation and necrosis of the lesion cells. To cultivate clinical operational skills among medical personnel, verify the hardware performance of new ablation devices, and optimize surgical planning, the field of medical engineering widely uses interventional ablation simulation systems for in vitro testing. Ablation simulation systems typically use physical biomimetic phantoms to replace real human tissue, allowing operators to perform in vitro puncture and energy output procedures.

[0003] In existing in vitro interventional ablation simulation practices, commonly used biomimetic phantoms are mainly formulated from conventional polymer matrix materials such as polyacrylamide gel, gelatin, or agar, with a certain concentration of conductive salt solution added during the formulation process to impart initial static conductivity. In actual simulation operations, testers directly insert the ablation probe of a commercial medical device into these traditional static gel phantoms, activate the ablation device to output high-frequency electromagnetic energy, and the phantom matrix absorbs the energy, generating heat and causing a local temperature rise. The testing system uses this to observe the spatial distribution of the thermal field or for basic device connection testing.

[0004] However, existing interventional ablation simulation systems have significant limitations in realistically reproducing the dynamic electrical evolution of physiological tissues. When real biological tissues undergo high-frequency electromagnetic ablation, their local impedance exhibits a dynamic evolution characteristic: a decrease in the initial heating phase followed by a sharp increase during carbonization, in response to changes in temperature and cell morphology. Existing conventional gel phantom materials, upon heating, fail to undergo corresponding structural abrupt changes in their internal ion-conducting networks. This prevents the pure physical hardware level from replicating the initial impedance decline caused by tissue dehydration and shrinkage, and the subsequent instantaneous jump in polarization resistance due to deep tissue carbonization. This distortion in the electrical feedback mechanism means that the control hardware loop of the external ablation device cannot acquire realistic dynamic impedance jump signals from the phantom, rendering existing simulation systems unsuitable for evaluating the power adaptive adjustment capabilities of ablation devices. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an interventional ablation simulation system and method. It solves the problem that existing interventional ablation in vitro simulation systems, due to their use of static phantoms, cannot realistically reproduce the dynamic evolution characteristics of multi-physics fields in living tissue during the ablation process at a purely physical hardware level. Specifically, it addresses the technical deficiencies of existing systems in failing to adequately simulate the impedance drop followed by a sudden increase caused by thermal dehydration and carbonization of lesion tissue, the dynamic heat sink effect caused by microvascular closure due to heat, and the dynamic mechanical tactile feedback during puncture. These deficiencies lead to the inability to accurately verify the adaptive power adjustment performance of the ablation device and the clinical operating feel of the physician.

[0006] To achieve the above objectives, the present invention provides the following technical solution: The first aspect of the present invention provides an interventional ablation simulation system, comprising: a dynamic electrothermal biomimetic matrix module, an adaptive microfluidic perfusion network module, and a circulation dynamics and interface module.

[0007] The dynamic electrothermal biomimetic matrix module uses a temperature-sensitive porous hydrogel elastomer as its substrate, with liquid metal microdroplets dispersed within it. An adaptive microfluidic infusion network module is pre-installed within the dynamic electrothermal biomimetic matrix module. This module includes microfluidic channels distributed within the temperature-sensitive porous hydrogel elastomer, with a thermosensitive shape memory polymer valve layer attached to the inner wall of each channel. The circulation power and interface module includes a microcirculation power pump, a fluid tank, and a device access interface. The output of the microcirculation power pump is connected to the input of the microfluidic channels, and the output of the microfluidic channels is connected to the fluid tank, forming a fluid circulation loop for the cooling working fluid. The device access interface includes a loop electrode and a probe clamping and excitation assembly. The loop electrode is electrically connected to the temperature-sensitive porous hydrogel elastomer, and the device access interface is used to connect external ablation equipment.

[0008] The technical solution of this invention constructs a hardware feedback architecture with multi-physics coupling, and its internal structural linkage and physical evolution mechanism is as follows: During the electrothermal conversion and initial deformation phases of the system operation, the external ablation device outputs electromagnetic energy through the ablation probe. Conductive ions in the saline solution within the temperature-sensitive porous hydrogel elastomer generate Joule heating under the influence of electromagnetic energy. When the local temperature exceeds the lower critical dissolution temperature of the temperature-sensitive porous hydrogel elastomer, it undergoes a hydrophobic phase transition and volume shrinkage, applying mechanical compressive stress to the internal liquid metal microdroplets. When this mechanical compressive stress exceeds the yield strength of the gallium oxide film on the surface of the liquid metal microdroplets, the gallium oxide film physically ruptures. The liquid alloy within adjacent liquid metal microdroplets breaks through the oxide interface and fuses, forming a primary conductive pathway, resulting in a decrease in local impedance of the dynamic electrothermal biomimetic matrix module. This mechanism of primary conductive pathway formation achieves a physically equivalent simulation of the physiological phenomenon of impedance decrease in real lesion tissue during the initial heating stage.

[0009] As heat conduction occurs, the system enters the thermosensitive action and heat sink stripping stage. When the local temperature of the microfluidic channel reaches the trigger temperature threshold of the thermosensitive shape memory polymer valve layer, the thermosensitive shape memory polymer valve layer transitions from a glassy state to a highly elastic state, releasing the internally stored mechanical stress and recovering to its initial permanent contraction shape. This radial-centripetal contraction physically closes the lumen, blocking the flow of the cooling medium, thereby stripping the dynamic heat sink effect provided by the adaptive microfluidic infusion network module. Due to the cessation of convective heat transfer, local heat accumulation occurs. When the temperature exceeds the water vaporization temperature and the carbonization temperature threshold of the material, the saline component inside the thermosensitive porous hydrogel elastomer boils and vaporizes, physically destroying the three-dimensional polymer skeleton and synergistically severing the continuous electron transport path connecting the liquid metal droplets. The breakage of the primary conductive path causes a momentary increase in polarization resistance, forming an impedance jump physical signal for external ablation equipment to detect and adjust the output power.

[0010] Furthermore, to achieve hardware simulation of the abnormal electrical short-circuit state caused by massive bleeding due to vascular perforation, the secondary branch channels of the microfluidic pipeline have designated vulnerable sections. These vulnerable sections are equipped with a sacrificial layer wall whose melting threshold temperature is between the trigger temperature threshold and the carbonization temperature threshold. A highly conductive ionic liquid, dissolving a high concentration of free metal ions, circulates inside the microfluidic pipeline. When the local temperature of the vulnerable section exceeds the melting threshold temperature of the sacrificial layer wall, the sacrificial layer wall melts, creating a physical rupture in the vulnerable section. The highly conductive ionic liquid leaks outward through the physical rupture into the interior of the temperature-sensitive porous hydrogel elastomer. The highly conductive ionic liquid, through chemical erosion and osmotic pressure, destroys and mixes with the gallium oxide film on the surface of the liquid metal microdroplets, constructing a low-impedance physical pathway between the ablation probe and the loop electrode. This low-impedance physical pathway physically covers the primary conductive pathway, causing the dynamic electrothermal biomimetic matrix module to exhibit a low-resistance short-circuit state.

[0011] Furthermore, to generate tactile feedback resistance corresponding to the physical spatial location, the system also includes a tactile sensing channel embedded within a defined spatial boundary region of the dynamic electrothermal biomimetic matrix module. The tactile sensing channel contains a shear-thickening fluid whose apparent viscosity increases with shear rate. A probe clamping and excitation assembly is clamped and fixed to the outside of the ablation probe and drives the ablation probe to generate high-frequency micromechanical vibration. This high-frequency micromechanical vibration forms a mechanical wave within the temperature-sensitive porous hydrogel elastomer and is physically coupled to the shear-thickening fluid. The vibrational energy of the mechanical wave is converted into high-frequency shear stress, causing the local fluid shear rate to exceed the critical threshold for thickening phase transition, transforming the shear-thickening fluid from a low apparent viscosity state to a high apparent viscosity solid-like state. The increase in the local structural mechanical stiffness of the tactile sensing channel is transmitted to the periphery through the internal polymer network of the temperature-sensitive porous hydrogel elastomer, causing the ablation probe to experience a reverse physical action of puncture resistance when it touches this spatial boundary region, thus forming physical tactile feedback resistance.

[0012] The second aspect of this invention provides an interventional ablation simulation method, applied to the interventional ablation simulation system provided in the first aspect of this invention, comprising the following steps: After the system is started, the micro-circulation power pump pumps the cooling working fluid into the microfluidic pipeline to form a convective heat transfer field. At this time, the dynamic electrothermal biomimetic matrix module is in a hydrated state and exhibits a capacitive impedance state. When the external ablation device is activated, the ablation probe outputs electromagnetic energy, and the dynamic electrothermal biomimetic matrix module is heated and dehydrated and shrinks, causing adjacent liquid metal droplets to come into contact with each other to form a primary conductive path, resulting in a decrease in polarization resistance. As heating continues, heat is conducted to the adaptive microfluidic infusion network module. When the local temperature reaches the trigger temperature threshold of the thermosensitive shape memory polymer valve layer, the thermosensitive shape memory polymer valve layer undergoes a phase change and generates centripetal radial contraction, blocking the flow of the cooling working fluid. When the flow of the cooling medium is obstructed, causing convective heat transfer to stop, local heat accumulation occurs in the dynamic electrothermal biomimetic matrix module. The temperature-sensitive porous hydrogel elastomer undergoes carbonization, leading to structural damage. The primary conductive path breaks, causing the polarization resistance to increase, which triggers the external ablation device to adjust the output power.

[0013] This invention provides an interventional ablation simulation system and method. It has the following beneficial effects: 1. This invention employs a dynamic electrothermal biomimetic matrix module with liquid metal microdroplets dispersed inside a temperature-sensitive porous hydrogel elastomer. In the initial stage of electromagnetic energy heating, the hydrogel dehydration and shrinkage forces the liquid metal microdroplets to fuse and form a primary conductive path, resulting in a decrease in impedance. During continuous heating and carbonization, the continuous electron transport path is cut off, causing a jump in polarization resistance. This invention achieves a hardware equivalent simulation of the electrical evolution process of impedance first decreasing and then rapidly increasing during the ablation of real tissue.

[0014] 2. This invention integrates fractal tree-like microfluidic channels within a dynamic electrothermal biomimetic matrix module and attaches a thermosensitive shape memory polymer valve layer with a specific glass transition temperature to the inner wall of the channels. It utilizes the circulating flow of the cooling working fluid to simulate vascular convection heat transfer and induces the valve layer to undergo centripetal radial contraction to physically close the lumen when the local temperature reaches the trigger threshold. This achieves the hardware feedback simulation of the dynamic heat sink effect of the vascular network inside real physiological organs and the coagulation and closure action of blood vessels under heat.

[0015] 3. This invention utilizes a tactile sensing channel containing a shear-thickening fluid arranged in parallel within a spatial boundary region, and a probe clamping and excitation assembly clamped outside the ablation probe. The high-frequency micromechanical vibration generated by the ablation probe propagates outward and is converted into high-frequency shear stress within the shear-thickening fluid, causing changes in the apparent viscosity of the fluid and an increase in the local structural stiffness. This achieves the evolution of the mechanical distribution characteristics and the generation of tactile feedback resistance when the ablation probe is against a specific spatial boundary region and experiences the reverse action of puncture resistance. Attached Figure Description

[0016] Figure 1 This is a system architecture diagram of the present invention; Figure 2 This is a flowchart of the method of the present invention.

[0017] In the diagram: 10. Dynamic electrothermal biomimetic matrix module; 11. Temperature-sensitive porous hydrogel elastomer; 12. Liquid metal microdroplets; 20. Adaptive microfluidic infusion network module; 21. Microfluidic conduit; 211. Main conduit; 212. Primary branch conduit; 213. Secondary branch conduit; 214. Return main conduit; 22. Thermosensitive shape memory polymer valve layer; 23. Sacrificial layer wall; 24. Tactile sensing conduit; 30. Circulation power and interface module; 31. Microcirculation power pump; 32. Equipment access interface; 321. Loop electrode; 322. Probe clamping and excitation assembly; 33. Fluid tank; 34. Auxiliary power pump; 35. Auxiliary fluid tank; 40. Cooling medium; 41. Highly conductive ionic liquid; 42. Shear-thickening fluid; 50. Ablation probe. Detailed Implementation

[0018] The technical solutions in 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 the appendix Figure 1The present invention provides an interventional ablation simulation system, including: a dynamic electrothermal biomimetic matrix module 10, an adaptive microfluidic perfusion network module 20, and a circulation dynamics and interface module 30.

[0020] The dynamic electrothermal biomimetic matrix module 10 uses a temperature-sensitive porous hydrogel elastomer 11 as the substrate. Liquid metal microdroplets 12 are dispersed inside the temperature-sensitive porous hydrogel elastomer 11.

[0021] An adaptive microfluidic infusion network module 20 is pre-installed inside the dynamic electrothermal biomimetic matrix module 10. The adaptive microfluidic infusion network module 20 includes microfluidic channels 21 distributed inside a temperature-sensitive porous hydrogel elastomer 11. The inner wall of the microfluidic channels 21 is attached with a thermosensitive shape memory polymer valve layer 22.

[0022] The circulation power and interface module 30 includes a micro-circulation power pump 31, a fluid storage tank 33, and a device access interface 32. The output end of the micro-circulation power pump 31 is connected to the input end of the microfluidic pipeline 21, and the output end of the microfluidic pipeline 21 is connected to the fluid storage tank 33, forming a fluid circulation loop for the cooling working fluid. The device access interface 32 includes a loop electrode 321 and a probe clamping and excitation assembly 322. The loop electrode 321 is electrically connected to the temperature-sensitive porous hydrogel elastomer 11, and the device access interface 32 is used to connect to external ablation equipment.

[0023] See attached document Figure 2 , Figure 2 This is a flowchart of an interventional ablation simulation method according to an embodiment of the present invention. The method is applied to the aforementioned interventional ablation simulation system, and the specific workflow is as follows.

[0024] After system startup, the micro-circulation power pump 31 in the circulation power and interface module 30 starts. The micro-circulation power pump 31 pumps the cooling medium 40 into the microfluidic channel 21 of the adaptive microfluidic infusion network module 20 at a preset pressure head. The cooling medium 40 circulates within the microfluidic channel 21, forming a convective heat transfer field inside the dynamic electrothermal biomimetic matrix module 10. At this time, the dynamic electrothermal biomimetic matrix module 10 is in a hydrated state, and the liquid metal droplets 12 inside are separated by the material network of temperature-sensitive porous hydrogel elastomer 11, so the dynamic electrothermal biomimetic matrix module 10 exhibits a capacitive impedance state.

[0025] When the external ablation device is activated via the device access interface 32, the ablation probe 50 of the external ablation device pierces the designated area of ​​the dynamic electrothermal biomimetic matrix module 10. The external ablation device outputs electromagnetic energy through the ablation probe 50, forming a closed loop through the circuit electrode 321. The dynamic electrothermal biomimetic matrix module 10 absorbs the electromagnetic energy and generates heat. The temperature-sensitive porous hydrogel elastomer 11 undergoes dehydration and shrinkage deformation upon heating. The volume shrinkage of the temperature-sensitive porous hydrogel elastomer 11 causes adjacent liquid metal droplets 12 to come into contact with each other, forming a primary conductive path, resulting in a decrease in the local impedance of the dynamic electrothermal biomimetic matrix module 10.

[0026] As heating continues, heat is conducted from the dynamic electrothermal biomimetic matrix module 10 to the adaptive microfluidic infusion network module 20. When the local temperature of the microfluidic channel 21 reaches the trigger temperature threshold of the thermosensitive shape memory polymer valve layer 22, the thermosensitive shape memory polymer valve layer 22 undergoes a phase transition and produces centripetal radial contraction. The radial contraction reduces the flow cross-sectional area of ​​the microfluidic channel 21, blocking the flow of the cooling medium 40.

[0027] When the flow of the cooling medium 40 is obstructed, causing convective heat transfer to cease, localized heat accumulation occurs in the dynamic electrothermal biomimetic matrix module 10, leading to a temperature increase. The temperature-sensitive porous hydrogel elastomer 11 undergoes carbonization, resulting in structural damage. The primary conductive path breaks, and the polarization resistance of the dynamic electrothermal biomimetic matrix module 10 increases. The external ablation device detects the increased impedance signal through the ablation probe 50 and subsequently adjusts the output power.

[0028] The present invention provides a dynamic electrothermal biomimetic matrix module 10, comprising: a temperature-sensitive porous hydrogel elastomer 11 and liquid metal microdroplets 12 distributed inside the temperature-sensitive porous hydrogel elastomer 11.

[0029] The temperature-sensitive porous hydrogel elastomer 11 is made of a polymer network material with a low critical solution temperature, which can be a poly(N-isopropylacrylamide) copolymer. The low critical solution temperature of the polymer network material lies between the normal body temperature of human tissue and its ablation and solidification temperature. When the local temperature is below the low critical solution temperature of the polymer network material, the temperature-sensitive porous hydrogel elastomer 11 is in a hydrophilic swelling state. When the local temperature is above the low critical solution temperature of the polymer network material, the temperature-sensitive porous hydrogel elastomer 11 undergoes a hydrophobic phase transition, expelling internal water and producing volume shrinkage deformation.

[0030] The liquid metal microdroplets 12 are prepared using a gallium-indium alloy material that is liquid at room temperature. The micro-particle size distribution of the liquid metal microdroplets 12 is at the micrometer level. The liquid metal microdroplets 12 are dispersed in the polymer network pores of a temperature-sensitive porous hydrogel elastomer 11. The surface of the liquid metal microdroplets 12 has a spontaneously formed oxide film, which is a gallium oxide film, and the oxide film is used to maintain the structural morphology of the liquid metal microdroplets 12.

[0031] In the initial baseline state of the system, the temperature-sensitive porous hydrogel elastomer 11 absorbs moisture, causing the polymer network to expand. The individual liquid metal droplets 12 distributed within the polymer network are separated from each other by the matrix structure of the temperature-sensitive porous hydrogel elastomer 11.

[0032] In the overall composition distribution of the dynamic electrothermal biomimetic matrix module 10, the initial volume fraction of the liquid metal microdroplets 12 is configured to be lower than the conductivity percolation threshold of the system composed of the temperature-sensitive porous hydrogel elastomer 11 and the liquid metal microdroplets 12. There are no continuous electron transport paths between the individual liquid metal microdroplets 12. Under the initial baseline state of the system, the dynamic electrothermal biomimetic matrix module 10 exhibits high capacitive impedance physical characteristics.

[0033] The physical evolution process of the dynamic electrothermal biomimetic matrix module 10 provided by the present invention in the electrothermal conversion and primary deformation stages is as follows.

[0034] The external ablation device outputs high-frequency electromagnetic energy into the dynamic electrothermal biomimetic matrix module 10 via the ablation probe 50. The temperature-sensitive porous hydrogel elastomer 11 contains physiological saline. Under the action of high-frequency electromagnetic energy, the conductive ions in the physiological saline oscillate and rub against each other, generating Joule heating in a localized area. The accumulation of Joule heating leads to an increase in the local temperature of the temperature-sensitive porous hydrogel elastomer 11.

[0035] When the local temperature of the temperature-sensitive porous hydrogel elastomer 11 rises above the lower critical dissolution temperature of the polymer network material, a phase transition occurs in the molecular chain structure of the polymer network material. The polymer network material changes from a hydrophilic state to a hydrophobic state. The temperature-sensitive porous hydrogel elastomer 11 expels the bound water from its interior and undergoes macroscopic volume shrinkage deformation.

[0036] The volume shrinkage of the temperature-sensitive porous hydrogel elastomer 11 applies mechanical compressive stress to the liquid metal microdroplets 12 distributed inside the temperature-sensitive porous hydrogel elastomer 11. The mechanical compressive stress forces adjacent liquid metal microdroplets 12 to move closer to each other in spatial position.

[0037] When the mechanical compressive stress applied by the temperature-sensitive porous hydrogel elastomer 11 exceeds the yield strength of the gallium oxide film on the surface of the liquid metal microdroplet 12, the gallium oxide film physically ruptures. The liquid alloy inside adjacent liquid metal microdroplets 12 then fuses through the oxide interface.

[0038] The fused liquid metal microdroplets 12 connect within a localized region of the temperature-sensitive porous hydrogel elastomer 11, forming a continuous electron transport path. This continuous electron transport path constitutes the primary conductive pathway within the dynamic electrothermal biomimetic matrix module 10.

[0039] The formation of the primary conductive path alters the macroscopic electrical characteristics of the dynamic electrothermal biomimetic matrix module 10. The module transitions from an initial capacitive impedance state to a resistive impedance state. The external ablation device detects an initial decrease in the local impedance value of the module 10 via the ablation probe 50. This impedance decrease directly triggers the built-in power adaptive adjustment loop of the external ablation device, enabling it to automatically adjust its energy output based on the impedance change.

[0040] The adaptive microfluidic infusion network module 20 provided by the present invention includes microfluidic channels 21. The microfluidic channels 21 are distributed in three-dimensional space and are embedded inside the dynamic electrothermal biomimetic matrix module 10.

[0041] The microfluidic channels 21 are distributed in a fractal tree topology within the dynamic electrothermal biomimetic matrix module 10. The microfluidic channels 21 branch off progressively along the fluid flow direction, with the diameter decreasing progressively.

[0042] The microfluidic conduit 21 includes a main conduit 211, a primary branch conduit 212, a secondary branch conduit 213, and a return main conduit 214. The input end of the main conduit 211 extends to the outside of the dynamic electrothermal biomimetic matrix module 10. The output end of the main conduit 211 connects to the primary branch conduit 212 inside the dynamic electrothermal biomimetic matrix module 10. The primary branch conduit 212 further connects to the secondary branch conduit 213.

[0043] Secondary branch pipes 213 are interspersed within the internal region of the dynamic electrothermal biomimetic matrix module 10. The microfluidic pipe 21 has a flexible wall. The outer wall of the flexible pipe 21 is directly and physically bonded to the internal polymer structure of the temperature-sensitive porous hydrogel elastomer 11. The flexible wall of the microfluidic pipe 21 serves as the heat transfer interface between the temperature-sensitive porous hydrogel elastomer 11 and the cooling medium 40.

[0044] Each secondary branch pipe 213 merges sequentially after passing through the internal region of the dynamic electrothermal biomimetic matrix module 10. The merging end of the secondary branch pipes 213 connects to the return main pipe 214. The output end of the return main pipe 214 extends to the outside of the dynamic electrothermal biomimetic matrix module 10. The input end of the main pipe 211 and the output end of the return main pipe 214 serve as the physical channels for the cooling working fluid 40 to flow into and out of the adaptive microfluidic infusion network module 20, respectively.

[0045] The adaptive microfluidic perfusion network module 20 provided by the present invention includes a thermosensitive shape memory polymer valve layer 22. The thermosensitive shape memory polymer valve layer 22 is disposed inside the microfluidic channel 21.

[0046] The thermosensitive shape memory polymer valve layer 22 is made of a polymer material with a glass transition temperature, such as shape memory polyurethane. The glass transition temperature corresponds to a set trigger temperature threshold. The trigger temperature threshold is set to be consistent with the temperature at which real biological tissue undergoes thermal coagulation, and is between 60°C and 70°C. The thermosensitive shape memory polymer valve layer 22 is attached to the inner surface of the flexible wall of the microfluidic channel 21. The thermosensitive shape memory polymer valve layer 22 is distributed in a ring shape along the circumference of the microfluidic channel 21.

[0047] In the initial state of system operation, the local temperature of the microfluidic conduit 21 is lower than the trigger temperature threshold of the thermosensitive shape memory polymer valve layer 22. The thermosensitive shape memory polymer valve layer 22 is attached to the flexible inner surface of the primary branch conduit 212 or the secondary branch conduit 213. The thermosensitive shape memory polymer valve layer 22 is distributed in a ring shape along the circumference of the primary branch conduit 212 or the secondary branch conduit 213.

[0048] As the external ablation device outputs electromagnetic energy, the heat generated by the dynamic electrothermal biomimetic matrix module 10 is transferred to the microfluidic channel 21 through heat conduction. When the local temperature of the microfluidic channel 21 rises and reaches the trigger temperature threshold, the thermosensitive shape memory polymer valve layer 22 transitions from a glassy state to a highly elastic state.

[0049] After the transition from the glassy state to the elastic state, the thermosensitive shape memory polymer valve layer 22 releases the pre-stored mechanical stress within it. This release of mechanical stress drives the thermosensitive shape memory polymer valve layer 22 to undergo radial centripetal contraction deformation. The thermosensitive shape memory polymer valve layer 22 then recovers to its initial permanently contracted shape.

[0050] The radial centripetal contraction of the thermosensitive shape memory polymer valve layer 22 leads to a reduction in the local flow cross-sectional area of ​​the microfluidic channel 21. The contraction deformation continues until the local cavity of the microfluidic channel 21 physically closes. The physical closure of the cavity blocks the flow path of the cooling medium 40 inside the microfluidic channel 21, stopping the convective heat transfer of the cooling medium 40 inside the microfluidic channel 21.

[0051] The physical evolution process of the interventional ablation simulation system provided by this invention during the physical stripping stage of the local heat sink effect is as follows.

[0052] The radial centripetal contraction of the thermosensitive shape memory polymer valve layer 22 causes partial closure of the microfluidic channel 21, thereby blocking the flow path of the cooling medium 40 inside the microfluidic channel 21. The cessation of the cooling medium 40's flow causes the local microcirculation perfusion rate of the adaptive microfluidic perfusion network module 20 in the closed lumen region to decrease to zero.

[0053] Since the local microcirculation perfusion rate decays to zero, the convective heat transfer effect of the cooling medium 40 on the dynamic electrothermal biomimetic matrix module 10 is eliminated, thereby stripping away the dynamic heat sink effect provided by the adaptive microfluidic perfusion network module 20. The Joule heat generated inside the dynamic electrothermal biomimetic matrix module 10 cannot be transferred to the outside of the dynamic electrothermal biomimetic matrix module 10 through the cooling medium 40.

[0054] Joule heating accumulates in localized areas of the dynamic electrothermal biomimetic matrix module 10, causing a continuous rise in the local temperature of the temperature-sensitive porous hydrogel elastomer 11. When the local temperature of the temperature-sensitive porous hydrogel elastomer 11 exceeds the water vaporization temperature and the carbonization temperature threshold of the material, the saline solution inside the temperature-sensitive porous hydrogel elastomer 11 boils and vaporizes, resulting in deep dehydration and structural carbonization of the temperature-sensitive porous hydrogel elastomer 11, while the three-dimensional polymer skeleton is physically destroyed.

[0055] The significant loss of conductive ions from physiological saline and the physical disruption of the three-dimensional polymer framework of the temperature-sensitive porous hydrogel elastomer 11 synergistically severed the continuous electron transport paths connecting the individual liquid metal microdroplets 12. The physical breakage of the primary conductive pathway within the dynamic electrothermal biomimetic matrix module 10 caused a momentary increase in the polarization resistance of the module.

[0056] The increased polarization resistance of the dynamic electrothermal biomimetic matrix module 10 generates an impedance jump signal. The external ablation device detects this impedance jump signal through the ablation probe 50 and the loop electrode 321 of the device access interface 32. The impedance jump signal directly triggers the power cut-off protection hardware circuit of the external ablation device, causing the external ablation device to stop outputting high-frequency electromagnetic energy to the dynamic electrothermal biomimetic matrix module 10.

[0057] The adaptive microfluidic perfusion network module 20 provided by the present invention includes, in the complication simulation embodiment, a sacrificial tube wall 23 and a highly conductive ionic liquid 41.

[0058] The secondary branch pipe 213 has a designated vulnerable section. A sacrificial layer wall 23 is disposed in the vulnerable section of the secondary branch pipe 213. The sacrificial layer wall 23 constitutes the flexible wall body of the secondary branch pipe 213 in the vulnerable section, used to form a solid fluid boundary. The sacrificial layer wall 23 is made of a heat-melting polymer material. The heat-melting polymer material can be a low-melting-point polycaprolactone material.

[0059] The thermal melting threshold temperature of the sacrificial layer wall 23 is higher than the triggering temperature threshold of the thermosensitive shape memory polymer valve layer 22. The thermal melting threshold temperature of the sacrificial layer wall 23 is lower than the carbonization temperature threshold of the thermosensitive porous hydrogel elastomer 11 in the dynamic electrothermal biomimetic matrix module 10. When the local temperature of the microfluidic channel 21 rises and exceeds the thermal melting threshold temperature of the sacrificial layer wall 23, the sacrificial layer wall 23 undergoes thermal melting and physical rupture.

[0060] The fluid reservoir 33 in the circulation power and interface module 30 contains a highly conductive ionic liquid 41. In this complication simulation embodiment, the highly conductive ionic liquid 41 is used as the cooling medium 40 circulating inside the microfluidic pipeline 21. The microcirculation power pump 31 pumps the highly conductive ionic liquid 41 into the microfluidic pipeline 21. The highly conductive ionic liquid 41 continuously circulates within the cavity formed by the microfluidic pipeline 21 and the sacrificial layer wall 23.

[0061] The conductivity of the highly conductive ionic liquid 41 is higher than the overall conductivity of the dynamic electrothermal biomimetic matrix module 10 in a fully hydrated baseline state. The highly conductive ionic liquid 41 is prepared from an aqueous solution containing a high concentration of free metal ions, and a high concentration of sodium chloride aqueous solution can be used for the highly conductive ionic liquid 41.

[0062] In the initial stage of system operation, the sacrificial layer wall 23 maintains structural integrity. The highly conductive ionic liquid 41 is constrained within the cavity of the microfluidic channel 21 by the sacrificial layer wall 23. The highly conductive ionic liquid 41 is physically isolated from the external temperature-sensitive porous hydrogel elastomer 11 and liquid metal microdroplets 12. The conductivity of the highly conductive ionic liquid 41 does not interfere with the initial capacitive impedance baseline of the dynamic electrothermal biomimetic matrix module 10.

[0063] The physical evolution process of the interventional ablation simulation system provided by this invention in the stage of simulating vascular perforation complications is as follows.

[0064] The external ablation device continuously outputs high-frequency electromagnetic energy to the dynamic electrothermal biomimetic matrix module 10 through the ablation probe 50. The heat generated inside the dynamic electrothermal biomimetic matrix module 10 is conducted to the vulnerable section of the microfluidic channel 21. When the local temperature of the vulnerable section of the microfluidic channel 21 rises and exceeds the thermal melting threshold temperature of the sacrificial layer wall 23 material, the sacrificial layer wall 23 undergoes thermal melting.

[0065] The thermal melting of the sacrificial layer wall 23 causes physical perforations in the vulnerable section of the microfluidic channel 21, at which point the microfluidic channel 21 loses its boundary constraint on the internal fluid. Driven by the pumping head provided by the microcirculation power pump 31, the highly conductive ionic liquid 41 inside the microfluidic channel 21 leaks outward through the physical perforations.

[0066] The leaked highly conductive ionic liquid 41 enters the interior of the dynamic electrothermal biomimetic matrix module 10 and permeates into the polymer network pores of the temperature-sensitive porous hydrogel elastomer 11. The highly conductive ionic liquid 41 comes into physical contact with the liquid metal microdroplets 12 inside the temperature-sensitive porous hydrogel elastomer 11. The highly conductive ionic liquid 41 disrupts the gallium oxide film on the surface of the liquid metal microdroplets 12 through chemical erosion and osmotic pressure, promoting mixing between the liquid metal microdroplets 12 and the highly conductive ionic liquid 41.

[0067] The highly conductive ionic liquid 41 contains a high concentration of free metal ions. These free metal ions directly construct a conductive liquid network within the dynamic electrothermal biomimetic matrix module 10. This conductive liquid network forms a low-impedance physical pathway between the ablation probe 50 and the loop conductive electrode 321 of the device access interface 32. The permeation of the highly conductive ionic liquid 41 physically covers the original dielectric structure and primary conductive pathway of the temperature-sensitive porous hydrogel elastomer 11, causing a rapid decrease in the overall polarization resistance of the dynamic electrothermal biomimetic matrix module 10, resulting in a low-resistance short-circuit state.

[0068] The external ablation device detects a rapid decrease in polarization resistance via the ablation probe 50 and the loop electrode 321 of the device access interface 32. The control hardware circuit of the external ablation device receives the polarization resistance decrease signal and triggers the device's built-in abnormal state alarm, stopping the output of high-frequency electromagnetic energy.

[0069] The adaptive microfluidic infusion network module 20 provided by the present invention further includes a tactile sensing channel 24 and a shear-thickening fluid 42.

[0070] The tactile sensing channel 24 is embedded within the spatial boundary region defined inside the dynamic electrothermal biomimetic matrix module 10. The tactile sensing channel 24 and the microfluidic channel 21 are arranged in parallel in space. The tactile sensing channel 24 has an independent fluid chamber, and the fluid paths inside the tactile sensing channel 24 and the microfluidic channel 21 are not interconnected.

[0071] The tactile sensing conduit 24 contains a shear-thickening fluid 42. The shear-thickening fluid 42 is a non-Newtonian fluid and is a polyethylene glycol dispersion containing silica nanoparticles. The apparent viscosity of the shear-thickening fluid 42 increases with increasing internal shear rate.

[0072] The circulation power and interface module 30 includes an auxiliary power pump 34 and an auxiliary fluid storage tank 35. The output end of the auxiliary power pump 34 is connected to the input end of the tactile sensing pipe 24, and the output end of the tactile sensing pipe 24 is connected to the auxiliary fluid storage tank 35, forming an independent circulation loop for the shear-thickening fluid 42. The auxiliary power pump 34 is used to drive the shear-thickening fluid 42 to circulate within the tactile sensing pipe 24.

[0073] Under normal operating conditions of the interventional ablation simulation system, the auxiliary power pump 34 outputs a basic pumping head. The shear-thickening fluid 42 flows at a basic flow rate within the tactile sensing conduit 24. The fluid shear rate generated by this basic flow rate in the shear-thickening fluid 42 is below the critical threshold for the thickening phase transition of the shear-thickening fluid 42.

[0074] When the fluid shear rate is below the critical threshold for thickening phase transition, the shear-thickening fluid 42 maintains its low apparent viscosity. The shear-thickening fluid 42 flows smoothly within the tactile sensing conduit 24, maintaining the original mechanical puncture resistance baseline of the dynamic electrothermal biomimetic matrix module 10.

[0075] The physical evolution process of the interventional ablation simulation system provided by this invention in the tactile feedback generation stage is as follows.

[0076] The ablation probe 50 of the external ablation device moves within the dynamic electrothermal biomimetic matrix module 10. The probe clamping and excitation assembly 322 clamps and fixes the ablation probe 50 externally. The piezoelectric transducer element inside the probe clamping and excitation assembly 322 drives the ablation probe 50 to generate high-frequency micromechanical vibrations during operation. These high-frequency micromechanical vibrations form mechanical waves within the temperature-sensitive porous hydrogel elastomer 11. These mechanical waves propagate to the surrounding spatial medium, with the tip of the ablation probe 50 as the vibration source.

[0077] When the ablation probe 50 approaches the spatial boundary region where the tactile sensing conduit 24 is located, the temperature-sensitive porous hydrogel elastomer 11 transmits mechanical waves to the wall of the tactile sensing conduit 24. The mechanical waves pass through the wall of the tactile sensing conduit 24 and are physically coupled into the shear-thickening fluid 42 circulating inside the tactile sensing conduit 24.

[0078] The vibrational energy of the mechanical wave is converted into localized high-frequency shear stress within the shear-thickening fluid 42. This high-frequency shear stress increases the local fluid shear rate within the shear-thickening fluid 42. When the local fluid shear rate within the shear-thickening fluid 42 exceeds the critical threshold for thickening phase transition, a physical phase transition occurs within the shear-thickening fluid 42.

[0079] Under shear stress, the nanoparticles inside the shear-thickening fluid 42 undergo mutual compression and physical aggregation. In the localized stress region of the tactile sensing pipe 24, the shear-thickening fluid 42 transforms from a low-apparent viscosity fluid state to a high-apparent viscosity solid-like state. Consequently, the structural mechanical stiffness of the tactile sensing pipe 24 increases in the localized stress region.

[0080] The increase in the local structural mechanical stiffness of the tactile sensing channel 24 alters the mechanical distribution characteristics within the dynamic electrothermal biomimetic matrix module 10. This increase in local structural mechanical stiffness is transmitted to the periphery through the internal polymer network of the temperature-sensitive porous hydrogel elastomer 11, causing the dynamic electrothermal biomimetic matrix module 10 to exhibit high puncture resistance in the spatial boundary region where the tactile sensing channel 24 is located. When the tip of the ablation probe 50 abuts against the spatial boundary region where the tactile sensing channel 24 is located, it experiences a reverse physical action from the puncture resistance. This puncture resistance is transmitted outward along the rigid needle body of the ablation probe 50, forming a physical tactile feedback resistance that the operator can perceive.

[0081] When the ablation probe 50 moves away from the spatial boundary region where the tactile sensing pipe 24 is located or stops vibrating, the local fluid shear rate inside the shear-thickening fluid 42 decreases. The shear-thickening fluid 42 returns to a low apparent viscosity state, and the physical tactile feedback resistance disappears accordingly.

[0082] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An interventional ablation simulation system, characterized in that, include: The dynamic electrothermal biomimetic matrix module (10) uses a temperature-sensitive porous hydrogel elastomer (11) as a substrate, and liquid metal microdroplets (12) are dispersed inside the temperature-sensitive porous hydrogel elastomer (11). An adaptive microfluidic infusion network module (20) is pre-placed inside the dynamic electrothermal biomimetic matrix module (10). The adaptive microfluidic infusion network module (20) includes microfluidic channels (21) distributed inside the thermosensitive porous hydrogel elastomer (11). The inner wall of the microfluidic channel (21) is attached with a thermosensitive shape memory polymer valve layer (22). The circulating power and interface module (30) includes a micro-circulation power pump (31), a fluid storage tank (33) and a device access interface (32). The output end of the micro-circulation power pump (31) is connected to the input end of the microfluidic pipeline (21), and the output end of the microfluidic pipeline (21) is connected to the fluid storage tank (33), forming a fluid circulation loop for the cooling working fluid (40). The device access interface (32) includes a loop electrode (321) and a probe clamping and excitation assembly (322). The loop electrode (321) is electrically connected to the temperature-sensitive porous hydrogel elastomer (11). The device access interface (32) is used to connect to an external ablation device. When the external ablation device outputs electromagnetic energy through the ablation probe (50), the thermosensitive porous hydrogel elastomer (11) undergoes dehydration and shrinkage deformation due to heat, forcing adjacent liquid metal microdroplets (12) to contact each other and form a primary conductive path. As heat is conducted, when the temperature reaches the trigger temperature threshold of the thermosensitive shape memory polymer valve layer (22), the thermosensitive shape memory polymer valve layer (22) undergoes centripetal radial contraction to block the flow of the cooling working fluid (40), resulting in local heat accumulation and structural damage of the dynamic electrothermal biomimetic matrix module (10), which in turn causes an increase in polarization resistance.

2. The interventional ablation simulation system according to claim 1, characterized in that, The temperature-sensitive porous hydrogel elastomer (11) is made of poly(N-isopropylacrylamide) copolymer and its low critical dissolution temperature is between the normal body temperature of human tissue and the ablation and solidification temperature. The liquid metal microdroplet (12) is made of gallium indium alloy material, and the surface of the liquid metal microdroplet (12) has a gallium oxide film to maintain the structural morphology. In the initial baseline state of the system, the initial volume fraction of the liquid metal microdroplet (12) is configured to be lower than the conductive percolation threshold, and the dynamic electrothermal biomimetic matrix module (10) presents a high capacitive impedance state.

3. The interventional ablation simulation system according to claim 2, characterized in that, The thermosensitive porous hydrogel elastomer (11) contains physiological saline components, and the conductive ions in the physiological saline generate Joule heat under the action of electromagnetic energy. When the local temperature exceeds the lower critical dissolution temperature, the temperature-sensitive porous hydrogel elastomer (11) undergoes a hydrophobic phase transition and volume shrinkage, applying mechanical compressive stress to the liquid metal microdroplet (12). When the mechanical compressive stress exceeds the yield strength of the gallium oxide film, the gallium oxide film physically ruptures, and the liquid alloy inside the adjacent liquid metal microdroplets (12) breaks through the oxide interface and fuses to form the primary conductive path, causing the local impedance of the dynamic electrothermal biomimetic matrix module (10) to decrease.

4. The interventional ablation simulation system according to claim 1, characterized in that, The microfluidic conduit (21) is distributed according to a fractal tree topology, including a main conduit (211), a primary branch conduit (212), a secondary branch conduit (213), and a return main conduit (214). The microfluidic conduit (21) has a flexible pipe wall, and the outer wall of the flexible pipe wall is directly physically bonded to the temperature-sensitive porous hydrogel elastomer (11). The thermosensitive shape memory polymer valve layer (22) is attached to the inner surface of the flexible tube wall of the primary branch pipe (212) or the secondary branch pipe (213); the thermosensitive shape memory polymer valve layer (22) is made of shape memory polyurethane and has a glass transition temperature corresponding to the trigger temperature threshold, which is between 60°C and 70°C.

5. The interventional ablation simulation system according to claim 4, characterized in that, When the temperature reaches the trigger temperature threshold, the thermosensitive shape memory polymer valve layer (22) changes from a glassy state to a highly elastic state, releases the internal pre-stored mechanical stress and recovers to the initial permanent contraction shape, resulting in physical closure of the lumen and stripping away the dynamic heat sink effect provided by the adaptive microfluidic infusion network module (20). Thermal accumulation causes the local temperature to exceed the threshold of water vaporization temperature and material carbonization temperature. The saline component inside the thermosensitive porous hydrogel elastomer (11) boils and vaporizes, and the three-dimensional polymer skeleton is physically destroyed. This synergistically cuts off the continuous electron transport path connecting the liquid metal droplets (12), causing the polarization resistance to rise instantaneously and triggering the power cut-off protection hardware circuit of the external ablation device.

6. The interventional ablation simulation system according to claim 4, characterized in that, The secondary branch pipe (213) has a set vulnerable section, and the vulnerable section is provided with a sacrificial layer pipe wall (23) made of low melting point polycaprolactone material. The hot melt threshold temperature of the sacrificial layer pipe wall (23) is higher than the trigger temperature threshold of the thermosensitive shape memory polymer valve layer (22) and lower than the carbonization temperature threshold of the thermosensitive porous hydrogel elastomer (11). The fluid tank (33) contains a highly conductive ionic liquid (41), which is used as a cooling medium (40) circulating inside the microfluidic pipeline (21). The highly conductive ionic liquid (41) is prepared by dissolving an aqueous solution containing a high concentration of free metal ions.

7. The interventional ablation simulation system according to claim 6, characterized in that, When the local temperature of the vulnerable section exceeds the heat melting threshold temperature of the sacrificial layer pipe wall (23), the sacrificial layer pipe wall (23) undergoes heat melting and physical puncture is generated in the vulnerable section; Driven by the micro-circulation power pump (31), the highly conductive ionic liquid (41) seeps outward through physical pores and enters the interior of the temperature-sensitive porous hydrogel elastomer (11). The highly conductive ionic liquid (41) destroys the gallium oxide film on the surface of the liquid metal microdroplet (12) through chemical erosion and osmotic pressure and mixes with it, constructing a low-impedance physical path between the ablation probe (50) and the loop electrode (321), physically covering the primary conductive path, so that the dynamic electrothermal biomimetic matrix module (10) presents a low-resistance short-circuit state.

8. The interventional ablation simulation system according to claim 1, characterized in that, The adaptive microfluidic infusion network module (20) further includes a tactile sensing channel (24) embedded in a spatial boundary region within the dynamic electrothermal biomimetic matrix module (10). The tactile sensing channel (24) contains a shear-thickening fluid (42), the apparent viscosity of which increases with the increase of the internal shear rate. The circulating power and interface module (30) further includes an auxiliary power pump (34) and an auxiliary fluid tank (35). The output end of the auxiliary power pump (34) is connected to the input end of the tactile sensing pipe (24), and the output end of the tactile sensing pipe (24) is connected to the auxiliary fluid tank (35), forming an independent circulation loop for the shear thickening fluid (42).

9. The interventional ablation simulation system according to claim 8, characterized in that, The probe clamping and excitation assembly (322) clamps and fixes the ablation probe (50) to the outside and drives the ablation probe (50) to generate high-frequency micromechanical vibration. The high-frequency micromechanical vibration forms a mechanical wave inside the temperature-sensitive porous hydrogel elastomer (11) and is physically coupled to the shear-thickening fluid (42) circulating inside the tactile sensing channel (24). The vibration energy of the mechanical wave is converted into high-frequency shear stress. When the local fluid shear rate exceeds the critical threshold of thickening phase change, the shear thickening fluid (42) changes from a low apparent viscosity state to a high apparent viscosity solid-like state. The increase in the local structural mechanical stiffness of the tactile sensing channel (24) is transmitted to the outer periphery through the internal polymer network of the temperature-sensitive porous hydrogel elastomer (11), so that when the ablation probe (50) comes into contact with the spatial boundary area, it is subjected to the reverse physical action of the puncture resistance, forming physical tactile feedback resistance.

10. A method for simulating interventional ablation based on the system described in any one of claims 1 to 9, characterized in that, Includes the following steps: After the system is started, the micro-circulation power pump (31) pumps the cooling working fluid (40) into the microfluidic pipeline (21) to form a convective heat transfer field. At this time, the dynamic electrothermal biomimetic matrix module (10) is in a hydrated state and exhibits a capacitive impedance state. When the external ablation device is activated, the ablation probe (50) outputs electromagnetic energy, and the dynamic electrothermal biomimetic matrix module (10) undergoes dehydration and shrinkage deformation when heated, causing adjacent liquid metal microdroplets (12) to come into contact with each other to form a primary conductive path, resulting in a decrease in polarization resistance; As heating continues, heat is conducted to the adaptive microfluidic infusion network module (20). When the local temperature reaches the trigger temperature threshold of the thermosensitive shape memory polymer valve layer (22), the thermosensitive shape memory polymer valve layer (22) undergoes a phase change and generates centripetal radial contraction, blocking the flow of the cooling working fluid (40). After the flow of the cooling medium (40) is obstructed, causing the convective heat transfer to stop, the dynamic electrothermal biomimetic matrix module (10) locally generates heat accumulation, the temperature-sensitive porous hydrogel elastomer (11) undergoes carbonization, resulting in structural damage, the primary conductive path breaks, causing the polarization resistance to increase, triggering the external ablation device to adjust the output power.

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