A positioning marker device for breast tumor surgery

Abstract

This invention belongs to the field of medical devices, specifically relating to a positioning and marking device for breast tumor surgery. The device includes a guide needle, a tissue marker clip, a delivery component, and a flexible outer sheath fitted over the needle. The flexible outer sheath is made of a biocompatible shape memory polymer. At body temperature, it is in a first physical state, puncturing the tissue along with the needle. Upon gentle thermal stimulation, it transforms into a second physical state, significantly reducing friction with the needle, allowing the needle to be withdrawn independently, leaving the flexible outer sheath in place within the body, forming a stable guiding channel from the body surface to the marked location. The device can also integrate an intelligent temperature control unit, achieving closed-loop regulation through temperature sensor feedback to ensure safe and effective thermal stimulation. This invention solves the intraoperative positioning problem caused by lesion shrinkage after chemotherapy, combining long-term placement safety, puncture rigidity, and placement flexibility, significantly improving the accuracy and reliability of surgical positioning.

Description

Technical Field

[0001] This invention belongs to the field of medical devices, specifically relating to a positioning marker device for breast tumor surgery. Background Technology

[0002] This invention belongs to the field of medical device technology, specifically relating to a positioning device for surgery after neoadjuvant chemotherapy for breast cancer, and more particularly to a tumor and lymph node positioning device that can be safely and permanently placed and provides reliable guidance for precise intraoperative resection.

[0003] Neoadjuvant chemotherapy (NAC) is an important treatment for locally advanced and some early-stage breast cancers. It can significantly shrink tumor size, thereby reducing surgical difficulty and improving the success rate of breast-conserving and axillary-conserving surgeries. However, when chemotherapy is highly effective and the tumor even achieves pathological complete remission, the lesions may become invisible or difficult to identify on imaging. This poses a significant challenge to the subsequent precise surgical resection of the primary lesion and metastatic lymph nodes.

[0004] Currently, two main preoperative localization methods are used clinically, but both have significant shortcomings. The first method involves implanting a metal marker clip (such as a titanium clip) into the tumor before chemotherapy. This marker is small (usually only about 2 mm) and can be visualized on imaging examinations. However, due to the limited availability of hybrid operating rooms in general hospitals, and the lack of effective real-time imaging methods in ordinary operating rooms, surgeons can only rely on preoperative image memory and palpation of the surgical area to locate it. In cases where the tumor has significantly shrunk or completely resolved, finding such tiny markers is extremely difficult, time-consuming, and may even fail, leading to an expanded surgical area or residual lesions.

[0005] The second method involves inserting a breast localization needle with a metal wire into the target area under ultrasound guidance on the day of surgery. While this method provides a physical puncture path, the needle body and the metal wire at its tail are quite rigid, which can easily cause discomfort to the patient during actual surgery and is not suitable for placement in the highly mobile, neurovascularized axillary lymph node area. Furthermore, for lesions that have significantly shrunk after chemotherapy, they may be difficult to clearly capture with ultrasound, leading to decreased accuracy in guided puncture.

[0006] In summary, current technologies lack a positioning device that can be safely placed long-term, adapt to deep and lymph node environments, and provide a stable and reliable intraoperative guiding pathway. Therefore, there is an urgent need for a positioning device to solve the surgical positioning challenges posed by tumor shrinkage after chemotherapy. Summary of the Invention

[0007] The present invention aims to provide a breast tumor and lymph node localization device that can be safely and permanently placed in the body, is soft and easy to fix, and provides a precise and stable guiding channel for surgery.

[0008] A positioning marker device for breast tumor surgery, comprising: The guide needle is rigid enough to puncture into the area of ​​the breast tumor and has an axial cavity from one end near the operator to the tip for puncture. Tissue marker clip, which is positioned within the axial cavity of the guide needle tube; A pusher assembly, movably disposed within an axial cavity, is used to push out a tissue marker clip from the tip of a guide needle tube; A flexible outer sheath is fitted over the guide needle cannula. The flexible outer sheath is made of a biocompatible polymer and has a first physical state at body temperature. In this first physical state, the friction between the flexible outer sheath and the outer wall of the guide needle cannula allows both to puncture the tissue. When subjected to a predetermined thermal stimulus, the flexible outer sheath can transform into a second physical state. In this second physical state, the friction between the flexible outer sheath and the outer wall of the guide needle cannula is significantly reduced, allowing the guide needle cannula to be withdrawn separately while leaving the flexible outer sheath in the body, thereby forming a guide channel from the body surface to the area where the tissue marker clip is located.

[0009] The positioning and marking device provided by this invention achieves separation of puncture and channel establishment by using a flexible outer sheath fitted around the guide needle. This sheath, which is used in conjunction with the guide needle under body temperature and exhibits significantly reduced friction after thermal stimulation, allows for independent puncture and channel establishment. This structure enables the guide needle to be withdrawn separately after the tissue marking clip is released, while the flexible outer sheath remains stably in place, forming a guide channel from the body surface directly to the marked area. This provides a clear and low-invasive tracking path for subsequent surgical instrument insertion or tumor localization. The exposed portion of the flexible outer sheath can be secured with a medical adhesive tape. Made of a biocompatible polymer, the flexible sheath's physical state can be controlled to change with temperature. This ensures overall rigidity during puncture while allowing for friction regulation under body temperature or slightly above-body temperature, significantly reducing traction and damage to surrounding tissues during needle withdrawal without requiring additional mechanical dissection, thus improving operational safety and patient comfort. This device integrates puncture, marking, and channel establishment functions into a compact structure with a simplified operating procedure. The channel created by the placement of a flexible outer sheath helps maintain the integrity of the puncture path and reduces path deviation caused by tissue rebound or bleeding, thereby improving the accuracy and reliability of intraoperative positioning. It is especially suitable for preoperative positioning and intraoperative guidance of deep or small breast tumors.

[0010] Optionally, the pushing component includes a pushing rod, and the pushing end of the pushing rod is provided with an elastic portion; The elastic part has elastic potential energy that expands outward in an unconstrained state. When the push rod is located in the axial cavity, the elastic part is constrained by the inner wall of the axial cavity and is in a radially contracted state. During the process of pushing the tissue marker clip to the tip with the push rod, the elastic part is in a contracted state under the constraint of the guide needle tube; When the distal end of the push rod is pushed to the conical tip region of the guide needle, the elastic part at least partially disengages from the constraint of the axial cavity and expands elastically outward to abut and engage with the inner wall of the tip region, thereby sealing the tip outlet of the guide needle. The material of the elastic part is preferably medical-grade polyurethane. This invention achieves an integrated function of tissue marker clip delivery and guide needle tip self-sealing by setting a push rod with a specific elastic part. The elastic part remains in a contracted state due to the constraint of the inner wall of the cavity when the push rod moves axially, ensuring a smooth and reliable pushing process; when it reaches the tip region, it can automatically expand and tightly abut against the conical inner wall, forming a physical seal. This design effectively prevents body fluid or tissue fragments from seeping back into the cavity through the tip opening during the placement of the flexible outer sheath and the withdrawal of the guide needle, reducing the risk of infection and ensuring channel cleanliness. Furthermore, when liquid is injected into the axial cavity subsequently, the liquid can circulate within the axial cavity without leakage. The elastic part is made of medical-grade polyurethane material, which not only has excellent biocompatibility and flexibility, but also its elastic deformation behavior is controllable and reversible. The material's properties allow the elastic portion to reliably expand in an unrestrained state and contract smoothly under cavity constraints, resisting fatigue with repeated use. This enhances the functional reliability and lifespan of the delivery component while meeting safety standards for contact with human tissue. The design integrates delivery and exit closure functions into a single, compact component. The closure action is automatically triggered at the end of the delivery rod's stroke, eliminating the need for additional steps, simplifying the surgical procedure, reducing clinical risks associated with forgetting or delaying exit closure, and improving the safety and efficiency of the entire positioning and marking operation.

[0011] Furthermore, the push assembly also includes a push housing; the push housing is connected to the needle tube via its first threaded portion and to the end cap via its second threaded portion; a seal is provided between the end cap and the push housing; The end cap has a first hole, the pusher housing has a second hole, and the needle tube has a third hole; the push rod and the push handle are fixedly connected; during operation, the push handle drives the push rod to pass through the first hole, the second hole, and the third hole in sequence and enter the interior of the guide needle tube. This invention achieves a "post-loading" delivery process for tissue marker clips by setting a pusher assembly with multi-level holes and a detachable sealing structure. This design allows clinical operators to first accurately puncture and fix the guide needle tube to the tumor target area, and then safely insert the tissue marker clip (such as a titanium clip) through the second hole in a sterile environment. Subsequently, an immediate seal is achieved using a sealing element, and the push rod is inserted. This process significantly improves operational flexibility, avoids accidental displacement or dislodgement of the marker clip during long-distance punctures, and minimizes the risk of external contaminants entering the body cavity along the delivery path. The delivery path passes sequentially through the first hole of the end cap, the second hole of the pusher housing, and the third hole of the needle tube, forming a highly coaxial and well-constrained delivery channel. This structured path ensures the stability and precise guidance of the push rod and the attached marker clip during its movement. It is particularly beneficial for real-time monitoring with ultrasound and other imaging techniques, allowing clear observation of the marker clip's trajectory (especially the titanium material which has excellent ultrasound imaging properties). This enables visualized and precise delivery from the surface inlet to the target site within the tumor. The sealing element, combined with a multi-level threaded connection structure (first threaded section, second threaded section), ensures the airtightness of the entire push channel during operation while enabling rapid modular assembly and disassembly of the components. This effectively maintains an internal sterile environment and contributes to subsequent liquid sealing. This push mechanism works synergistically with the pre-opened tissue marker clip. Once the marker clip is reliably delivered to the tip of the guide needle by the push rod and pushed out, it immediately and moderately opens within the tumor tissue due to its own elasticity, achieving rapid and secure anchoring. This "push-and-open" characteristic, combined with the fully visible push path, ensures high accuracy in marker placement and reliable marker retention, providing a clear and stable tissue target for subsequent surgical resection.

[0012] Specifically, the second orifice also has an injection channel and an outlet channel; the injection channel is connected to the injection section via a third threaded portion, and the outlet channel is connected to the outlet section via a fourth threaded portion; both the injection and outlet sections are connected to flexible tubes, which are connected to a micro water pump. This invention integrates the injection and outlet channels into the push assembly and connects them to the micro water pump, constructing a closed-loop controlled liquid circulation temperature control system. This structural design allows sterile saline solution preheated to body temperature (approximately 37°C) to serve as a safe and biocompatible heat transfer medium, circulating and perfusing within the internal region formed by the axial cavities (flowing sequentially through the first, second, and third orifices). This design, for the first time in a positioning and marking device, achieves precise and active control of the microenvironment temperature of the indwelling flexible outer sheath, providing a reliable and controllable external heat stimulus to trigger its physical state transformation. Through intelligent control of the circulation flow rate and time by the micro water pump, the system can maintain the internal region temperature stable within a preset range. This temperature control method is characterized by uniformity and gentleness. It ensures effective heat transfer to the flexible outer sheath, reliably transitioning it from the first physical state (high friction) to the second physical state (low friction), while strictly limiting the operating temperature to a safe range close to body temperature. This minimizes the risk of damage to surrounding healthy tissues due to overheating, enhancing the safety and controllability of the entire thermal triggering process. The fluid circulation system features a programmable "infusion-maintenance-drainage" operation. After completing the thermal stimulation and confirming the transition of the flexible outer sheath, the system can instruct the micro-pump to reverse its operation, completely draining the circulating fluid from the cavity. This step ensures that there is no large amount of residual fluid inside the system before the subsequent critical operation of withdrawing the guide needle, preventing fluid from flowing into human tissue and causing irritation during needle withdrawal.

[0013] Furthermore, this application also proposes a signal connection between the micro water pump and an intelligent control unit; the device also includes a first temperature sensor located at the junction of the guide needle tube and the tip, and a second temperature sensor located on the liquid outlet channel; both the first and second temperature sensors are signal-connected to the intelligent control unit. This invention constructs a real-time, dual-point monitoring intelligent temperature feedback system by adding a first and a second temperature sensor and connecting them to the intelligent control unit. The first temperature sensor directly monitors the critical temperature at the distal end of the guide needle tube (i.e., the tissue interface), while the second temperature sensor monitors the temperature of the outflowing liquid, thereby achieving synchronous monitoring of the "input end" (tissue contact point) and the "output end" (circulating medium) of the heat transfer process. This design upgrades the temperature control process from open-loop, experience-based operation to closed-loop, data-driven precise control, significantly improving the controllability and safety of the entire heat-triggered process. The intelligent control unit, as the core processing module of the system, receives and analyzes real-time temperature data from the dual sensors, enabling dynamic and precise control of the micro water pump's operating parameters (such as flow rate and start / stop). This closed-loop control mechanism ensures that the thermal stimulation applied to the flexible outer sheath and surrounding tissues remains within a preset safety window. It effectively reaches the temperature required to trigger the outer sheath's state transition while strictly preventing excessive local temperature from causing tissue thermal damage, achieving an optimal balance between safety and effectiveness. This intelligent integrated design significantly reduces reliance on the operator's personal experience. The system automatically adjusts circulation parameters based on real-time temperature feedback, maintaining a stable thermodynamic environment. This avoids the risks of insufficient heat (outer sheath transition failure) or excessive heat (tissue damage) that may result from inaccurate manual control, making the operation more standardized and reliable, and improving the consistency and predictability of surgical results. The dual-temperature sensor setup also provides verifiable data recording for the operation. The data from the first sensor directly reflects the heating status of the target tissue and is the most important direct evidence of safety; the data from the second sensor indirectly reflects the efficiency of heat transfer and the system's thermal balance. All of this data can be recorded and analyzed by the intelligent control unit, supporting not only intraoperative operational decisions (such as determining whether the state transition is complete) but also providing an objective data basis for postoperative review and process optimization, aligning with the development trend of intelligent and data-driven modern medical devices.

[0014] Preferably, the intelligent control unit is configured to execute a precise thermal triggering control program: controlling a micro-pump to drive liquid circulation within the axial cavity, and dynamically adjusting the parameters of the circulating liquid based on the temperature feedback from a first temperature sensor, so that the temperature of the inner wall of the guide needle is maintained between a first threshold higher than the glass transition temperature of the flexible outer sheath and a second threshold lower than the tissue damage temperature. This invention, by configuring the intelligent control unit to execute the precise thermal triggering control program, achieves intelligent, closed-loop, and precise control of the physical state transition process of the flexible outer sheath. This program, by acquiring the inner wall temperature of the guide needle in real time from the first temperature sensor, dynamically adjusts the parameters (such as flow rate and temperature) of the circulating liquid driven by the micro-pump, precisely maintaining the thermal stimulation temperature acting on the flexible outer sheath within a safe window between the first threshold higher than its glass transition temperature and the second threshold lower than the tissue damage temperature. This technical solution effectively solves the technical problems of traditional thermal triggering methods, such as temperature control relying on experience and the susceptibility to insufficient stimulation or overheating damage. By establishing a closed-loop control logic based on real-time feedback, this system ensures that thermal stimulation reliably triggers the complete transition of the flexible outer sheath from the first physical state to the second physical state, significantly reducing friction between it and the outer wall of the guide needle, thus creating conditions for subsequent non-invasive needle removal. Simultaneously, it strictly controls the upper temperature limit within a safe range, fundamentally avoiding the risk of thermal damage to surrounding healthy tissues due to excessively high local temperatures. This precise thermal triggering control program improves the reliability and consistency of regulating the thermal response behavior of the flexible outer sheath, reduces reliance on operator experience, and makes the operation of the entire positioning and marking device safer, more standardized, and more predictable.

[0015] Furthermore, the intelligent control unit is configured to: determine whether the thermo-physical state transition of the flexible outer sheath is complete based on the outflow liquid temperature data fed back by the second temperature sensor in the thermal triggering control program; and generate a status confirmation signal indicating that the guide needle can be safely withdrawn when the outflow liquid temperature changes tend to stabilize. This invention, by further configuring the intelligent control unit in the precise thermal triggering control program to determine whether the thermo-physical state transition of the flexible outer sheath is complete based on the outflow liquid temperature data fed back by the second temperature sensor, and generating a status confirmation signal when the outflow liquid temperature changes tend to stabilize, achieves a dual improvement in intelligent and objective determination of the transition endpoint of the flexible outer sheath and operational safety. This technical solution creatively uses the thermodynamic properties of the outflow liquid as a macroscopic monitoring indicator that indirectly reflects the microscopic physical state changes of the flexible outer sheath. By analyzing its temperature change curve over time, it can accurately identify the state of thermal equilibrium reached by the system when the flexible outer sheath material is saturated with heat and the phase transition is complete. This determination mechanism overcomes the risks of inaccurate timing judgment, delayed operation, or premature operation caused by relying on the operator's subjective experience or indirect inference from external images in the prior art.

[0016] By automatically generating clear status confirmation signals, the system provides operators with intuitive and reliable operating instructions, significantly reducing the risk of prematurely withdrawing the guide needle before the flexible outer sheath has fully transitioned to a low-friction state, which could lead to sheath displacement or traction damage to tissues. It also avoids unnecessary heat exposure from excessive thermal stimulation. This intelligent judgment function, combined with a closed-loop temperature control program, forms a complete "precise temperature control - intelligent judgment - safety prompt" operational loop. This upgrades core operational steps from experience-based "manual judgment" to data-driven "automatic confirmation," greatly improving the standardization, repeatability, and overall safety of the entire positioning and marking process. It further simplifies the operator's decision-making burden and optimizes the efficiency and smoothness of the surgical procedure.

[0017] A positioning and marking device for breast tumor surgery utilizes a guide needle made of medical-grade stainless steel. Medical-grade stainless steel, a mature and widely used material for puncture instruments in this field, has had its biocompatibility, mechanical strength, and sterilization performance thoroughly verified. This directly ensures the safety and reliability of the guide needle in clinical applications involving tissue puncture, reducing unknown risks and approval barriers associated with material introduction. More importantly, compared to other materials commonly used in puncture instruments (such as titanium alloys or some high-performance polymers), medical-grade stainless steel has a relatively higher thermal conductivity. This material characteristic allows heat to be conducted more quickly and efficiently through the guide needle wall to its external flexible sheath when circulating temperature-controlled fluid through the axial cavity. This efficient heat transfer significantly optimizes the response speed and spatial uniformity of applying a "predetermined thermal stimulus" to the flexible sheath, ensuring that the flexible sheath can synchronously and reliably reach its glass transition temperature along its entire length, especially in the deep region in contact with tissue, thereby achieving a complete and uniform transition from the first physical state to the second physical state. Therefore, the use of medical-grade stainless steel not only ensures the safety and feasibility of basic puncture functions based on its recognized advantages as a routine puncture material, but also provides an efficient and reliable heat transfer medium for the controllable transformation of the thermally induced frictional force of the flexible outer sheath through its excellent thermal conductivity. This fundamentally enhances the effectiveness and certainty of the thermal triggering mechanism, thereby synergistically improving the operational efficiency and clinical efficacy of the entire positioning and marking device.

[0018] A positioning and marking device for breast tumor surgery, wherein the predetermined thermal stimulation is the infusion of a liquid at a temperature of 37°C-39°C through the axial cavity of a guide needle, and the heat of the liquid is conducted to a flexible outer sheath via the guide needle wall. This invention proposes a safe, mild, and highly controllable thermal activation method by specifically defining the predetermined thermal stimulation as the infusion of a liquid at a temperature of 37°C-39°C through the axial cavity of the guide needle and providing a heat transfer path via the tube wall to the flexible outer sheath. This technical solution has several significant advantages: First, the setting of this temperature range (37°C-39°C) has clear synergistic advantages in biology and materials science. Its lower limit (37°C) is close to the core body temperature, while its upper limit (39°C) is significantly lower than the threshold that may cause thermal damage to tissues (generally considered >45°C), thus fundamentally ensuring the biosafety of the entire thermal stimulation process for human tissues. At the same time, this range fully covers and is slightly above the glass transition temperature (between 30°C and 32°C) typically set for flexible outer sheaths, providing sufficient and necessary thermal energy for their reliable transition from a high-friction first physical state to a low-friction second physical state.

[0019] Secondly, using sterile saline or other liquids as the heat transfer medium is a clinically mature, safe, and highly biocompatible method. Liquid infusion allows for large-area, uniform contact with the inner wall of the guide needle. Through a combination of heat convection and conduction, heat is efficiently and uniformly transferred along the entire needle axis, ensuring that the flexible outer sheath is heated synchronously along its entire length. This avoids incomplete frictional transitions caused by insufficient localized heat, thus improving the reliability of the state transition.

[0020] Furthermore, this internal fluid infusion heating method offers advantages such as precision, minimal invasiveness, and high operability. Heat is generated from within the guide needle and radiates outwards, directly acting on the flexible outer sheath to be altered. This concentrated and targeted energy avoids the skin burns, heat loss, or patient discomfort that can occur with large-area external heating of the puncture path. The intelligent temperature control system and temperature sensors work in perfect harmony, laying the physical foundation for precise closed-loop control of thermal stimulation parameters.

[0021] Therefore, the thermal stimulation method of the present invention not only provides a safe and effective activation means for the controllable physical state transformation of the flexible outer sheath, but also is highly integrated with the overall system design. It is a key and optimized operation step to realize the core function of "puncture, marking, and establishing a low-trauma guidance channel", which significantly improves the clinical safety, operational reliability and patient comfort of the entire positioning and marking device.

[0022] Optionally, the flexible outer sheath is a shape memory polymer with a specific formulation, which is in a first physical state below the glass transition temperature and transitions to a second physical state when the glass transition temperature is reached or exceeded. The glass transition temperature is set between 30°C and 32°C. The outer surface of the flexible outer sheath has a barbed structure. Optionally, the outer surface layer of the flexible outer sheath is a porous structure with several channels, and the surface of the porous structure is coated with a bioactive coating, which is a hydroxyapatite coating or a hydroxyapatite / collagen composite coating.

[0023] The flexible outer sheath is made of a specially formulated shape memory polymer, and its glass transition temperature (T) is achieved through polymer molecular design. g Materials that fall precisely within the temperature range of 30°C to 32°C. This can be achieved through material control techniques known in the art.

[0024] For polyurethane-based shape memory polymers, the T value is set by adjusting the chemical composition and ratio of their hard and soft segments. g Specifically, by controlling the molar content of hard segments (usually formed by the reaction of diisocyanate and chain extender) between 65% and 85%, and using soft segments of appropriate molecular weight (such as polycaprolactone diol or polyether diol), T can be obtained. g Materials located within the target temperature range of 30°C to 32°C. This range of hard segment content provides sufficient rigidity microregions to ensure the material's performance at T... g The following has the modulus required for puncture with the guide needle.

[0025] Using medical-grade polyurethane or polycaprolactone-based materials as the shape memory polymer substrate offers a core advantage: its glass transition temperature (TVT) is highly designable and controllable. By adjusting the chemical composition, molecular weight, and crosslinking density of the polymer chains, the TVT of the flexible outer sheath can be precisely set within the aforementioned physiologically compatible temperature range. This material characteristic allows the flexible outer sheath to stably maintain its first physical state (glassy state) below the TVT at room temperature. After the flexible outer sheath enters the human body, its temperature gradually rises to body temperature (approximately 37°C), exceeding its TVT. gThe outer sheath gradually transforms into a second physical state (softening, reduced modulus). However, this softening process is not instantaneous, and some residual friction remains between the outer sheath and the needle. This ensures sufficient rigidity during puncture and maintains high friction with the outer wall of the guide needle (the flexible outer sheath and guide needle are interference-fitted), thus meeting the mechanical requirements of joint puncture. When subjected to safe, mild thermal stimulation, it reliably reaches or exceeds its preset glass transition temperature, rapidly transforming into a second physical state (such as a rubbery state). This significantly reduces the material modulus and controllably decreases the friction with the needle's outer wall, creating crucial conditions for the separate and smooth withdrawal of the guide needle. The barbed structure provides a sophisticated unidirectional anchoring function. During puncture into the tissue, the barbs are supported by radial pressure from the surrounding tissue and the relatively high rigidity of the flexible outer sheath in the first physical state. Their free ends tend to bend elastically along the puncture direction or adhere to the outer wall of the sheath, greatly reducing insertion resistance and avoiding additional cutting or damage to tissues along the way. However, when the guide needle is heated and its friction decreases, and an attempt is made to withdraw it in the opposite direction, the free end of the barb will quickly open and embed itself into the surrounding soft tissue under the opposing force of the tissue, generating a reverse anchoring force. This mechanism ensures that when the guide needle is withdrawn, the flexible outer sheath can reliably resist the tendency to be carried out, thus remaining stably in place and accurately forming a guide channel from the body surface to the marked area.

[0026] This invention employs a thermodeformable flexible outer sheath in conjunction with a rigid guide needle for puncture. After releasing the marker clip, gentle thermal stimulation reduces the friction of the outer sheath, allowing for independent withdrawal of the needle. This results in the flexible outer sheath being stably retained within the body, forming a guiding channel. This design solves the problem of traditional metal positioning needles being unable to remain comfortably in place for extended periods due to their rigidity (especially in the axillary lymph node area), and overcomes the difficulty in locating the target in simple micro-marker implantation procedures. It achieves visualized, low-invasive, and stable long-term positioning guidance from the body surface to deep target areas. Attached Figure Description

[0027] To more clearly illustrate the embodiments of the present invention or the technical solutions in 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 merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the overall device of the present invention.

[0029] Figure 2 This is a cross-sectional view of the push rod of the present invention within the axial cavity.

[0030] Figure 3 This is a schematic diagram of the push rod of the present invention pushing out the tissue marker clip.

[0031] Figure 4 This is a schematic diagram showing the elastic portion of the push rod of the present invention open.

[0032] Figure 5 This is a cross-sectional view of the overall device of the present invention.

[0033] Figure 6 This is a schematic diagram of the placement of the tissue marker clip according to the present invention.

[0034] Figure 7 This is a schematic diagram of the liquid injection process of the present invention.

[0035] Figure 8 This is a schematic diagram of the push rod of the present invention.

[0036] Figure 9 This is a schematic diagram of the tissue marker clip of the present invention.

[0037] Figure descriptions: 1-Guide needle tube, 2-Push assembly, 3-Tissue marker clip, 4-Flexible outer sheath, 11-Tip, 12-Axial cavity, 13-Needle tube section, 21-Push rod, 22-Elastic part, 23-Push shell, 24-End cap, 25-Push handle, 26-Seal, 27-Injection section, 28-Outlet section, 29-Hose, 41-Barb, 131-Third hole, 231-First threaded section, 232-Second hole, 232a-Injection channel, 232b-Outlet channel, 233-Third threaded section, 234-Fourth threaded section, 235-Second threaded section, 241-First hole. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0040] Example 1: Reference Figures 1-5As shown, this embodiment provides a basic positioning and marking device, which mainly includes a guide needle tube 1, a tissue marker clip 3, a pusher assembly 2, and a flexible outer sheath 4. The guide needle tube 1 is a tubular structure with sufficient puncture rigidity, and its interior has an axial cavity 12 extending the entire length, with a tip 11 at the front end for piercing tissue. The tissue marker clip 3 is pre-positioned within this axial cavity 12. The pusher assembly 2 is movably disposed within the axial cavity 12, and its function is to push the tissue marker clip 3 out from the tip 11 of the guide needle tube 1 and release it to the target tumor tissue. The core innovative component, the flexible outer sheath 4, is fitted over the outside of the guide needle tube 1 (interference fit), and it is made of a biocompatible polymer material whose physical state can be controllably changed with temperature.

[0041] In actual surgical procedures, the surgeon first inserts the guide needle 1, fitted with a flexible outer sheath 4, percutaneously into the tumor area within the breast. Because the flexible outer sheath 4 is in its initial physical state at room temperature or upon initial insertion into the body, it elastically fits around the guide needle 1, and sufficient friction exists between it and the outer wall of the guide needle 1, allowing them to firmly adhere and complete the puncture process without violent slippage. Once the puncture is in place, the operator pushes the delivery component 2 to accurately deliver and extend the tissue marker clip 3 through the axial cavity 12, anchoring it inside the tumor or at its edge, thus completing the preoperative positioning marking. (Refer to...) Figure 9 As shown, tissue marker clip 3 is a common titanium marker clip, which is elastic and can open or shape after release to anchor tissue.

[0042] Reference Figure 5-7 As shown, after the marker clip is released, a stable channel needs to be established from the body surface directly to the marked location. At this time, a predetermined thermal stimulus is applied to the device, for example, by infusing mildly warmed sterile saline through the axial cavity 12 of the guide needle 1. The heat of the liquid is conducted through the wall of the guide needle 1 to the outer flexible sheath 4. When the temperature reaches a certain threshold, the material properties of the flexible sheath 4 change, entering a second physical state. In this state, the modulus of the flexible sheath 4 decreases, and the friction between it and the outer wall of the guide needle 1 is significantly reduced. Using this change, the doctor can smoothly withdraw the guide needle 1 together with the internal pusher component 2 from the flexible sheath 4, while the flexible sheath 4 remains stably in the original puncture path due to the friction with the surrounding tissue and its possible microstructures, thus forming a clear guide channel.

[0043] This embodiment cleverly separates the puncture instrument from the final indwelling channel instrument by introducing a flexible outer sheath 4 with thermosensitive friction. After tissue marking, this device can establish a minimally invasive, stable pathway. This pathway can be used to guide surgical instruments or reposition them during subsequent surgeries, effectively reducing problems such as tissue rebound, channel closure, or bleeding interference caused by direct needle aspiration in traditional methods, thus improving the accuracy and reliability of surgical positioning.

[0044] Example 2: Reference Figures 2-7 As shown, the positioning marker device in this embodiment includes all the core components of embodiment 1, with improvements mainly focused on the specific structure of the pushing component 2. (Refer to...) Figure 8 As shown, the push assembly 2 includes a slender push rod 21, with an elastic portion 22 made of medical-grade polyurethane at its distal end. In its natural state, the elastic portion 22 tends to expand outwards. However, when the push rod 21 is located inside the axial cavity 12 of the guide needle tube 1, the inner wall of the axial cavity 12 constrains the elastic portion 22, keeping it in a radially contracted state. This ensures that the push rod 21 can smoothly deliver the tissue marker clip 3 to the tip 11. The key design is that when the push rod 21 continues forward after pushing out the marker clip, and its distal elastic portion 22 enters the region of the tapered tip 11 at the front end of the guide needle tube 1, the elastic portion 22 breaks free from the complete constraint of the axial cavity 12 and expands outwards due to its material elasticity. Ultimately, it tightly abuts against and engages with the tapered inner wall of the tip 11, forming a physical barrier that immediately seals the outlet of the guide needle tube 1.

[0045] To achieve a more flexible and safer surgical procedure, the push assembly 2 is also designed with a rear loading mechanism. This mechanism includes a push housing 23, and further, the proximal end of the guide needle tube 1 is integrally formed or fixedly connected to the needle tube portion 13. The proximal end of the push housing 23 has a first threaded portion 231, which mates with the corresponding threaded structure on the needle tube portion 13 to achieve a detachable connection between the two. The distal end of the push housing 23 has a second threaded portion 235, which mates with the corresponding threaded structure on the end cap 24. Through the first threaded portion 231 and the second threaded portion 235, a stable assembly is achieved between the modules of the push assembly 2 and with the guide needle tube 1. In addition, a sealing element 26 is provided between the end cap 24 and the push housing 23 to ensure the airtightness of the connection. The end cap 24 has a first hole 241 at its center, the push housing 23 has a corresponding second hole 232, and the end of the needle tube portion 13 has a third hole 131. These three holes together form a coaxial through path. During the procedure, the surgeon first inserts the guide needle 1 and the flexible outer sheath 4 to the target location and fixes them in place. Then, under sterile conditions, the tissue marker clip 3 is safely inserted through the second hole 232 on the pusher shell 23. Next, the end cap 24 is tightened and sealed with the seal 26. Finally, the pusher rod 21, which is fixedly connected to the pusher handle 25, is inserted through the first hole 241 of the end cap 24, passes through the second hole 232 and the third hole 131 in sequence, and enters the axial cavity 12. Pushing it forward completes the delivery and release of the marker clip.

[0046] This embodiment significantly improves the operational safety and accuracy of the device by integrating the self-sealing elastic part 22 and the post-loading push-out shell 23. The self-sealing mechanism effectively prevents body fluids or tissue fragments from flowing back into the cavity and causing contamination or blockage during subsequent thermal stimulation and withdrawal of the guide needle 1. The post-loading process allows the tissue marker clip 3 to be inserted after the puncture is in place, avoiding the risk of accidental displacement of the marker clip during long-distance punctures and enabling precise placement under real-time imaging guidance such as ultrasound. These two improvements, together with the indwellable flexible outer sheath 4, constitute a more reliable positioning and marking device that better meets the needs of precise clinical operations.

[0047] Example 3: See attached document Figure 5-7As shown, this embodiment provides a highly integrated intelligent positioning and marking device. Based on a device with post-loading and self-sealing functions, it integrates a precise closed-loop liquid circulation temperature control system and an intelligent control unit. The core of the system's fluid pathway lies in the injection channel 232a and the outlet channel 232b added to the push-out housing 23. The push-out housing 23 is correspondingly provided with a third threaded portion 233 and a fourth threaded portion 234. The injection section 27 is threadedly connected to the injection channel 232a via the third threaded portion 233, and the outlet section 28 is threadedly connected to the outlet channel 232b via the fourth threaded portion 234. Both the injection section 27 and the outlet section 28 are connected to flexible tubes 29, which are connected to a micro water pump, thus forming a complete liquid circulation loop. This allows sterile saline solution preheated to 37℃-39℃ to circulate within the system, efficiently transferring heat through the wall of the guide needle tube 1 to the external flexible outer sheath 4. To achieve precise control and endpoint determination of the thermal stimulation process, this system introduces an intelligent control mechanism based on dual-sensor feedback. A first temperature sensor is precisely embedded in the wall of the guide needle 1 near the tip 11 to monitor the temperature of this critical area, the needle interface, in real time and directly. A second temperature sensor is installed on the liquid outlet channel 232b to continuously monitor the temperature of the outflowing circulating liquid. These two sensors are connected in real time to an intelligent control unit.

[0048] The core of the regulation mechanism is the precise thermal triggering control program embedded in the intelligent control unit. Once the program is activated, a micro-pump begins driving the temperature-controlled liquid circulation. The intelligent control unit uses the reading from the first temperature sensor as the core feedback parameter, comparing it in real-time with a preset temperature control window. The lower limit of this window is set slightly higher than the glass transition temperature of the flexible outer sheath 4 to ensure effective triggering of the state transition; the upper limit is set to a conservative value significantly lower than the tissue thermal damage threshold to ensure absolute safety. When the temperature fed back by the first sensor is lower than the target window, the control unit dynamically adjusts the power of the micro-pump to increase the flow rate, or instructs the heating module to slightly increase the temperature of the injected liquid, thereby enhancing heat transfer power. Conversely, if the monitored temperature approaches or reaches the upper limit, the flow rate is immediately reduced or heating is paused, and even unheated liquid can be briefly introduced for buffering to prevent overheating. This closed-loop negative feedback mechanism, with the first sensor as the direct target and liquid circulation as the regulation means, can overcome individual tissue differences and environmental interference, precisely stabilizing the thermal stimulation acting on the flexible outer sheath 4 within a safe and effective narrow range.

[0049] The program sets a target temperature range, such as the lower limit T. l =37°C (ensuring it is above the glass transition temperature of the outer sheath), upper limit T h =39°C (ensure it is well below the tissue thermal damage threshold). When the program starts, set an initial, relatively gentle fluid flow rate V0.

[0050] Assuming the operating room ambient temperature is 22°C and the initial temperature of the patient's internal tissues is approximately 37°C, the initial system parameters are set as follows: Injected fluid temperature T. i =39.0°C.

[0051] When the system starts up, it first reads the current temperature of the tip of the guide needle via the first temperature sensor, and records it as the initial temperature T. t In clinical practice, T t Typically below core body temperature, in this embodiment T t The initial value is 34.0°C. The control algorithm first calculates T. t The initial upward slope was low. Due to the low initial flow rate, the slope was also low. The algorithm determined that a slightly stronger heat input was needed to initiate effective heating, therefore the pump rate was increased to V1 = 120 mL / min (the maximum pump rate set for the initial stage of the system). After approximately 90 seconds, T... t The temperature rises to 37.6°C. The algorithm calculates the deviation of the current temperature from the target median (38°C). Based on a scaling factor (e.g., k = 30 μL / min / °C, meaning the pump speed is adjusted by 30 μL / min for every 1°C deviation), it calculates that a moderate increase in flow rate is needed, and thus smoothly adjusts the pump speed to V2 = 132 μL / min. This slight increase accelerates the heating process while avoiding temperature oscillations or pressure fluctuations caused by sudden changes in flow rate. When T t Once the algorithm reaches and stabilizes near its ideal operating point of 38°C, it enters a milliliter-level fine-tuning mode. For example, when T is detected... t There was a slight decreasing trend of 0.1°C, and the algorithm might slightly increase the pump rate from V2 = 132 μL / min to 135 μL / min to compensate for the minor heat loss. Throughout the maintenance phase, the pump rate V typically fluctuated within a very narrow range of 100 μL / min to 150 μL / min, thereby controlling temperature fluctuations within the guide needle 1.

[0052] The revised algorithm logic (based on bias-based proportional regulation and integral anti-drift) combined with extremely low flow parameters (100 μL / min to 150 μL / min) has been validated using a full-size prototype in a simulated tissue model. Experimental data show that this microflow control scheme can smoothly and uniformly raise the tip temperature from body temperature to the target working range within approximately 3-5 minutes and maintain it stably, with its heat transfer efficiency and safety redundancy fully meeting clinical requirements. This ensures that the flexible outer sheath 4 can complete a reliable state transition in a controlled, mild thermal environment, providing a core guarantee for the safety of the entire system.

[0053] While precisely controlling the temperature, the intelligent control unit also performs a parallel intelligent judgment task based on thermodynamic analysis to determine the timing of the state transition. Its core lies in analyzing the temperature change curve of the outflowing liquid to determine whether the material phase transition of the flexible outer sheath 4 has reached the thermal equilibrium point, i.e., the state transition is complete. This algorithm continuously collects the outflowing liquid temperature values ​​from the second temperature sensor and records data points at fixed time intervals (e.g., once per second), forming a temperature-time series. Internally, the algorithm maintains a dynamically calculated time window, such as data from the past 60 seconds, and calculates the linear regression slope of the temperature series within this window in real time, or simplifies it to calculating the average temperature change rate between the start and end points within the window.

[0054] To illustrate with a concrete example: Assume the temperature of the injected liquid is constant at 39.0°C. Initially, due to the significant heat absorption by the flexible outer sheath 4 and surrounding cold tissue, the outflowing liquid temperature may only be 30.5°C. As the cycle progresses, the intelligent control unit records a temperature value every second. In the first 60-second window, the outflowing temperature rises from 30.5°C to 34.2°C, with an average rate of change (slope) calculated as (34.2-30.5) / 60 = 0.062°C / second. At this point, the slope is high, indicating that the system is in a state of strong heat absorption and a phase transition is underway. As time progresses, in the next window from 120 to 180 seconds, the outflowing temperature slowly rises from 37.8°C to 38.4°C, and the calculated slope decreases to (38.4-37.8) / 60 = 0.010°C / second. The intelligent control unit compares the currently calculated real-time slope with a preset threshold (e.g., 0.015°C / second). When the algorithm detects that the slope value is consistently below the judgment threshold for three consecutive calculation windows (approximately three minutes), it infers that the temperature rise of the outflowing liquid has entered a plateau phase, the system's heat absorption is approaching saturation, and the phase transition process of the flexible outer sheath 4 is essentially complete. To increase the robustness of the judgment, the algorithm can also use absolute temperature difference for auxiliary verification. For example, in the above example, if the difference between the current average temperature of the outflowing liquid (e.g., 38.6°C) and the temperature of the injected liquid (39.0°C) is less than a preset tolerance (e.g., 0.5°C) when the slope meets the condition, this further confirms that the system is very close to thermal equilibrium. Once all logical conditions are met, the intelligent control unit immediately generates a high-confidence status confirmation signal. This algorithm transforms the abstract concept of "transformation completion" into a mathematical analysis of continuous, objective physical data. Its judgment does not rely on the operator's subjective experience, thus ensuring that each operation can proceed safely at the optimal and consistent time, greatly improving the system's standardization level and reliability.

[0055] In this embodiment, the key parameters of the intelligent judgment algorithm based on thermodynamic analysis executed by the intelligent control unit (such as the duration of the calculation window and the number of consecutive windows used to determine equilibrium) need to be determined through preliminary experimental verification and optimization of the system. This ensures the robustness and reliability of the algorithm in clinical scenarios. The following uses the determination of the judgment condition of "three consecutive calculation windows" as an example to illustrate the experimental verification method and logic behind it.

[0056] Researchers constructed an in vitro experimental model with thermal properties similar to human breast tissue and used a complete prototype positioning marker device for simulation. During the experiment, continuous time-series temperature data of the outflowing liquid were precisely recorded throughout the entire physical state transition process of the flexible outer sheath 4 under typical thermal stimulation parameters (e.g., injected liquid at 39°C). Analysis of this large amount of experimental data clearly showed the pattern of the temperature rise curve from a rapid rise phase, a transition phase, and finally a plateau phase. The research goal is to find a reliable, automated criterion to accurately capture this inflection point from the end of the transition phase to the beginning of the stable plateau phase. Preliminary algorithm testing shows that relying solely on the slope of a single calculation window below a threshold to issue a completion signal is highly susceptible to short-term fluctuations in temperature data or noise, leading to false positives (i.e., prematurely determining completion). For example, when the phase transition is not yet complete, a brief illusion of temperature stability may occur due to instantaneous small changes in flow rate. In practical operation, this could lead to the guide needle being prematurely withdrawn before the friction of the flexible outer sheath has sufficiently decreased, posing a risk of sheath displacement or tissue traction. Furthermore, the test used the criterion that the slope of two consecutive calculation windows was below a threshold. Although the anti-interference capability was improved, a certain proportion of false positives were still observed in some experimental data, especially when there were significant differences in tissue characteristics. During the transition period, there may be a slow, plateau-like upward phase lasting about two window durations. If this phase is mistakenly judged as completed, there is still a certain risk. By analyzing the statistical patterns of the data, it was found that when the slope of three consecutive calculation windows (corresponding to about 180 seconds of real-time monitoring data) is stably maintained below a low threshold, the system has experienced a sufficiently long stable heat transfer phase, and the probability that the corresponding outflow temperature curve has truly entered the plateau phase is extremely high. This criterion achieved the best balance in experimental verification: it can effectively filter out the brief "pseudo-stable" phase caused by various reasons during the transition period, keeping the false positive rate at an extremely low level; at the same time, since the window duration (e.g., 60 seconds) and the total judgment time (180 seconds) are designed within a reasonable clinical operational tolerance range, it does not cause unnecessary or excessively long waiting times, avoiding the inefficiency caused by false negatives (i.e., excessively delayed judgment). Therefore, the setting of "three consecutive calculation windows" is based on the optimal solution obtained between the accuracy (safety) of judgment and the timeliness (efficiency) of operation after statistical analysis of experimental data.

[0057] In summary, this embodiment integrates liquid circulation temperature control, dual-point temperature monitoring, and intelligent closed-loop control to construct a safe, accurate, and intuitive advanced positioning and marking platform.

[0058] Example 4: This embodiment further refines and optimizes the materials and microstructure of key components in the aforementioned embodiments. These design choices are crucial material foundations for ensuring the entire positioning and marking device achieves its intended functions, particularly the two core objectives of "controllable thermally induced frictional force transformation" and "stable channel placement." Firstly, the guide needle 1 is preferably made of medical-grade stainless steel. This choice is based not only on its rigorously validated biocompatibility, excellent mechanical strength, and ease of sterilization as a mature puncture material, but more importantly on its relatively high thermal conductivity. During system operation, as the temperature-controlled liquid circulates within the axial cavity 12, the stainless steel tube wall acts as a highly efficient heat transfer channel, rapidly and uniformly conducting the heat of the liquid to the entire inner surface of the tightly fitted flexible outer sheath 4. This efficient heat transfer ensures that the "predetermined thermal stimulus" applied to the flexible outer sheath 4 has excellent response speed and spatial consistency, allowing the outer sheath to synchronously and reliably reach its state transition temperature along its entire length, especially in the portion located deep within the tissue. This creates fundamental conditions for low-resistance withdrawal of the guide needle 1.

[0059] Secondly, the core material of the flexible outer sheath 4 is specified as a material with a specific glass transition temperature (T). g Medical shape memory polymers, such as polyurethane-based shape memory polymers with specific formulations, are described in the invention. Through precise molecular design, their T... g The temperature window is set between 30°C and 32°C, slightly below to close to human body temperature. This temperature window setting has a dual advantage: during room temperature or puncture procedures, when the ambient temperature is below T... g The flexible outer sheath 4 is in a glassy state (i.e., the first physical state), with a high modulus, providing the necessary support rigidity and generating sufficient static friction with the outer wall of the stainless steel needle tube to ensure stable puncture as a whole. When subjected to a safe thermal stimulus of 37℃-39℃ transmitted from within the system, the temperature of the flexible outer sheath 4 material reaches and exceeds its T0 value. g Upon entering the rubbery state (i.e., the second physical state), the modulus decreases significantly, the material softens, and the friction between it and the outer wall of the syringe decreases sharply, thus achieving smooth separation between the two.

[0060] Furthermore, to ensure that the flexible outer sheath 4 remains stably anchored within the tissue after the guide needle 1 is withdrawn, its outer surface is designed with a precise micron-scale barb structure 41. These barbs 41 employ a gradient stiffness design: thicker at the base and thinner towards the tip. During puncture into the tissue, the barb tips bend in the direction of tissue compression, minimizing insertion resistance. However, when the guide needle 1 is withdrawn after heating, although the outer sheath material softens overall, the barb structure, due to its geometry and the elastic recovery characteristics of the material itself, can still deform under the reverse force of the tissue and form a reliable anchorage with the surrounding soft tissue. Specifically, when the guide needle 1 is withdrawn, the barbs are subjected to the reverse force of the tissue; their relatively thick base provides effective support, while the tips undergo elastic deformation and hook into the soft tissue fiber network, forming a kind of "soft mechanical interlock." In addition, the barb surface may have a microtexture or be coated with a biocompatible coating (such as a medical silicone layer) to further increase the frictional adhesion with the tissue. This anchoring mechanism does not rely on the material being in a highly rigid puncture state. Instead, after overall softening, it achieves stable retention through optimized local structural design and surface characteristics, thereby ensuring that the flexible outer sheath 4 stably forms a reliable guiding channel.

[0061] Alternatively, as a more advanced preferred option, the outer surface layer of the flexible outer sheath 4 can be configured as a porous structure with interconnected channels and coated with a hydroxyapatite or collagen composite coating. This design not only further improves biocompatibility but also promotes the ingrowth of surrounding tissue cells into the porous structure, achieving biointegration and thus providing ultimate long-term stability for guiding channels that require prolonged placement.

[0062] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art may make some modifications to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but these should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0063] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A positioning marker device for breast tumor surgery, characterized in that, include: The guide needle (1) has sufficient rigidity to puncture into the breast tumor area and has an axial cavity (12) from one end near the operator to the tip (11) for puncture. Tissue marker clip (3), which is disposed within the axial cavity (12) of the guide needle tube (1); A push assembly (2), which is movably disposed within the axial cavity (12), is used to push the tissue marker clip (3) out from the tip (11) of the guide needle tube (1); A flexible outer sheath (4) is fitted over the outside of the guide needle tube (1). The flexible outer sheath (4) is made of a biocompatible polymer and has a first physical state at body temperature. In this first physical state, the friction between the flexible outer sheath (4) and the outer wall of the guide needle tube (1) allows both to puncture the tissue. When subjected to a predetermined thermal stimulus, the flexible outer sheath (4) can be transformed into a second physical state. In this second physical state, the friction between it and the outer wall of the guide needle tube is significantly reduced, allowing the guide needle tube to be withdrawn separately while leaving the flexible outer sheath (4) in the body, thereby forming a guide channel from the body surface to the area where the tissue marker clip (3) is located.

2. The positioning marker device for breast tumor surgery according to claim 1, characterized in that, The pushing component (2) includes a pushing rod (21), and the pushing end of the pushing rod (21) is provided with an elastic part (22); the guide needle tube (1) includes a needle tube part (13) for connecting to the pushing component (2); The elastic part (22) has elastic potential energy that expands outward in an unconstrained state. When the push rod (21) is located in the axial cavity (12), the elastic part (22) is constrained by the inner wall of the axial cavity (12) and is in a radially contracted state. During the process of pushing the tissue marker clip (3) to the tip (11) by the push rod (21), the elastic part (22) is in a contracted state under the limitation inside the guide needle tube (1); When the distal end of the push rod (21) is pushed to the region of the tapered tip (11) of the guide needle tube, the elastic part (22) is at least partially released from the constraint of the axial cavity (12) and expands elastically outward to abut and engage with the inner wall of the tip (11) region, thereby sealing the tip (11) outlet of the guide needle tube (1).

3. The positioning marker device for breast tumor surgery according to claim 2, characterized in that, The push component (2) also includes a push shell (23) and an end cap (24); The push-out housing (23) is provided with a first threaded portion (231) for threaded connection with the needle tube portion (13); The push-out housing (23) is also provided with a second threaded portion (235) for threaded connection with the end cap (24); A sealing element (26) is provided between the end cap (24) and the push-out housing (23); The end cap (24) is provided with a first hole (241), the push shell (23) is provided with a second hole (232), and the needle tube (13) is provided with a third hole (131). The push rod (21) is fixedly connected to the push handle (25); during operation, the push handle (25) drives the push rod (21) to pass through the first hole (241), the second hole (232) and the third hole (131) in sequence and enter the interior of the guide needle tube (1).

4. The positioning marker device for breast tumor surgery according to claim 3, characterized in that, The second hole (232) is also provided with an injection channel (232a) and an outlet channel (232b), and the pusher housing (23) is provided with a third threaded part (233) and a fourth threaded part (234). The push assembly (2) further includes an injection section (27) and a liquid outlet section (28). The injection section (27) is threadedly connected to the liquid injection channel (232a) through the third threaded section (233), and the liquid outlet section (28) is threadedly connected to the liquid outlet channel (232b) through the fourth threaded section (234). Both the injection section (27) and the liquid outlet section (28) are connected to hoses (29), and the hoses (29) are connected to a micro water pump.

5. The positioning marker device for breast tumor surgery according to claim 4, characterized in that, The miniature water pump is connected to an intelligent control unit via a signal connection. The positioning marking device also includes a first temperature sensor disposed at the junction of the guide needle tube (1) and the tip (11) and a second temperature sensor disposed on the liquid outlet channel (232b); Both the first temperature sensor and the second temperature sensor are connected to the intelligent control unit via signal transmission.

6. The positioning marker device for breast tumor surgery according to claim 5, characterized in that, The intelligent control unit is configured to execute a precise thermal triggering control program: control the micro water pump to drive the liquid to circulate in the axial cavity (12), and dynamically adjust the parameters of the circulating liquid based on the temperature feedback from the first temperature sensor, so that the temperature of the inner wall of the guide needle (1) is maintained between a first threshold higher than the glass transition temperature of the flexible outer sheath (4) and a second threshold lower than the tissue damage temperature.

7. The positioning marker device for breast tumor surgery according to claim 6, characterized in that, The intelligent control unit is also configured to: determine whether the thermo-physical state transition of the flexible outer sheath (4) is complete based on the outflow liquid temperature data fed back by the second temperature sensor in the thermal trigger control program; and generate a status confirmation signal indicating that the guide needle tube (1) can be safely removed when the outflow liquid temperature changes tend to stabilize.

8. The positioning marker device for breast tumor surgery according to claim 1, characterized in that, The guide needle tube (1) is made of medical-grade stainless steel.

9. The positioning marker device for breast tumor surgery according to claim 1, characterized in that, The predetermined thermal stimulation is to inject a liquid at a temperature of 37°C-39°C into the axial cavity (12) of the guide needle tube (1), and the heat of the liquid is conducted to the flexible outer sheath (4) through the tube wall of the guide needle tube (1).

10. The positioning marker device for breast tumor surgery according to claim 1, characterized in that, The flexible outer sheath (4) is made of medical shape memory polymer material. It is in the first physical state below the glass transition temperature and transforms into the second physical state when the glass transition temperature is reached or exceeded. The glass transition temperature is set between 30°C and 32°C. The outer surface of the flexible outer sheath (4) is provided with barbs (41).

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