A transjugular transhepatic biopsy assembly and method of use thereof

Abstract

The application discloses a transjugular transhepatic biopsy assembly and a use method thereof, relates to the field of liver biopsy instruments, and is configured to cooperate with an image-guided device, establish a working channel in a hepatic vein through a transjugular vein, and implement a transjugular biopsy device for tissue cutting and sampling. The transjugular biopsy device comprises a shell, a channel establishment module arranged at a proximal end of the shell and used for establishing an intravascular channel, and a tissue cutting module arranged in the channel establishment module and used for obtaining a tissue sample in target liver parenchyma. The transjugular biopsy assembly realizes airtight capture, anti-pollution flow guide and visualized accurate operation on the liver tissue sample under the transjugular vein path through the integration of a special biopsy needle with a one-way elastic valve and a spiral flow guide pattern, a surface anti-adhesion functional coating and a high-visualization accurate positioning structure, and effectively solves the technical problems of easy blood pollution of a sample, easy broken and falling of tissue and a large operation blind area in a traditional method.

Description

Technical Field

[0001] This invention relates to liver biopsy instrument technology, specifically to a transcervical transhepatic biopsy component and its method of use. Background Technology

[0002] Accurate diagnosis of parenchymal liver diseases, especially focal liver tumors (such as primary liver cancer and metastatic cancer) and diffuse liver diseases (such as unexplained liver fibrosis and cirrhosis), heavily relies on high-quality histopathological examination. Percutaneous liver biopsy is the gold standard method for obtaining liver tissue samples. However, for patients with severe coagulation disorders, massive ascites, lesions located on the liver surface or adjacent to important blood vessels / bile ducts, and some indications for transjugular intrahepatic portosystemic shunt (TIPS), traditional percutaneous puncture carries a high risk of bleeding, bile leakage, and tumor implantation through the needle tract.

[0003] Transjugular liver biopsy (TJLB), as an alternative interventional technique, establishes a working channel through the jugular vein-inferior vena cava-hepatic vein pathway, allowing for the puncture of the hepatic vein to obtain tissue samples. Bleeding through this pathway can be drained back into the venous system, theoretically significantly reducing the aforementioned risks, making it particularly suitable for high-risk patients. Currently, clinical TJLB often employs a matching metal cannula and an automated ejector biopsy gun system. Examples include a fully automated biopsy needle disclosed in Publication No. CN118948349B and a liver sampling biopsy puncture needle disclosed in Publication No. CN115530887A.

[0004] However, the existing biopsy needles are not yet perfect in terms of structural design and functional configuration, making it difficult to efficiently and reliably obtain complete strip-shaped liver tissue samples from the hepatic veins, which limits the sampling success rate and pathological quality.

[0005] Insufficient sampling efficiency and quality: Existing biopsy needles have a simple tissue groove design when puncturing liver parenchyma, resulting in low tissue capture rate. During the ejection and retraction process, the obtained soft liver tissue is easily dislodged from the groove or crushed by compression, leading to insufficient or fragmented samples. Multiple punctures are often required, increasing operation time and the risk of vascular injury.

[0006] Risks of sample contamination and loss: Since the biopsy needle operates within the hepatic vein, its tissue groove is easily filled and washed away by backflowing blood before, during, and after sampling, resulting in a large amount of blood dilution of the obtained sample and affecting the accuracy of pathological diagnosis. Simultaneously, backflowing blood may also wash away small tissue fragments within the groove, causing sample loss.

[0007] Operational controllability and precision need improvement: The design of the standard biopsy needle tip may cause tissue snagging or deviation when penetrating the liver capsule and parenchyma, affecting the accuracy of the puncture path. In addition, the clarity of the needle tip under fluoroscopy or ultrasound is limited, and the judgment of the needle tip bevel orientation (which determines the cutting direction) is not intuitive enough, which is not conducive to precise targeting of small lesions.

[0008] Potential risks of tumor cell adhesion and needle tract seeding: Although it is a venous route, repeated insertion and withdrawal of the biopsy needle may lead to contamination with tumor cells. Its surface characteristics may cause cell adhesion. Theoretically, there is still a very low probability of intra-needle tract seeding risk, which is an issue that needs to be avoided in interventional device design.

[0009] Therefore, designing a biopsy device that can stably establish vascular access via the transjugular vein, efficiently obtain complete strip tissue samples from the liver parenchyma, and simultaneously prevent blood backflow, needle groove blockage, cancer cell implantation, and precise needle tip imaging and positioning has become an urgent technical problem to be solved. Summary of the Invention

[0010] The purpose of this invention is to provide a transcervical and transhepatic biopsy component and its method of use, so as to solve the problems of low sampling efficiency, easy sample contamination and loss, and insufficient operational accuracy caused by the imperfect structure of the biopsy needle in the prior art.

[0011] To achieve the above objectives, the present invention provides the following technical solution: a transjugular hepatic biopsy assembly, configured to cooperate with an image-guided device to establish a working channel within the hepatic vein via the jugular vein and perform tissue cutting and sampling. The biopsy device includes a housing, a channel establishment module disposed proximal to the housing for establishing an intravascular access, and a tissue cutting module disposed within the channel establishment module for obtaining tissue samples from the target liver parenchyma.

[0012] The channel establishment module includes a guide sheath and a guide member, wherein the guide member is a slender component that can be inserted into the internal channel of the guide sheath, and the guide sheath is a tubular component with a development mark at its distal end;

[0013] The tissue cutting module is a disposable coaxial cutting needle with a tissue groove on its needle core. The tail end of the tissue groove is equipped with a one-way elastic valve. The inner wall of the tissue groove is equipped with a spiral guide pattern and the edge of the groove is equipped with a chamfered edge and covered with a micron-level smooth coating.

[0014] The inner side of the housing is provided with a firing mechanism for driving the coaxial cutting needle to pop forward relative to the guide sheath, and the outer side of the housing is provided with a firing key for triggering the firing mechanism.

[0015] Furthermore, the tip of the disposable coaxial cutting needle is a beveled blade combined with a double beveled cutting surface and is equipped with an annular metal imaging mark. The outer surface of the disposable coaxial cutting needle is coated with a low-adsorption, tumor-repellent coating.

[0016] Furthermore, the one-way elastic valve is a silicone duckbill valve, which consists of two flexible leaflets arranged in a Y shape and embedded in the tissue groove at the end of the needle core. The one-way elastic valve closes in its natural state, opens under tissue compression to allow tissue to enter the groove, and automatically closes after the tissue fills the groove to prevent backflow of blood or tissue fluid.

[0017] Furthermore, the spiral guide groove is a shallow-pitch spiral groove with a pitch of 0.3 to 0.8 mm and a depth of 0.05 to 0.1 mm. The direction of the shallow-pitch spiral groove is consistent with the needle core ejection / retraction movement, which is used to generate eddies during the movement to push residual blood and small tissue blocks to the bottom of the groove.

[0018] Furthermore, the micron-level smooth coating is a polytetrafluoroethylene or diamond-like carbon film with a surface roughness Ra≤0.1μm, covering the tissue groove opening and inner wall to reduce tissue adhesion.

[0019] Furthermore, the low-adsorption tumor cell-repellent coating is a diamond-like carbon film or a heparin composite coating, covering the outer surface of the core of the disposable coaxial cutting needle (including the exposed section of the core and the section in contact with the outer sheath).

[0020] Furthermore, the annular metal imaging marker is a platinum-iridium alloy ring or a gold-plated layer, with a width of 0.5–1.0 mm, and the position and angle of the needle tip are clearly visible under ultrasound or X-ray / CT.

[0021] Furthermore, the angle between the beveled cutting edge of the needle tip and the axis of the needle body is 30-45°, and the double beveled cutting surface is axe-shaped to prevent snagging on tissue.

[0022] A method of using a transcervical and transhepatic biopsy kit includes the following steps:

[0023] S1: Preoperative preparation and puncture path planning. Under the monitoring of image-guided equipment (such as ultrasound, DSA or CT), assess and plan the puncture path from the jugular vein to the target hepatic vein, and determine the target area of ​​the liver parenchyma.

[0024] S2: Guide positioning, insert the guide into the target hepatic vein branch via the internal jugular vein and confirm the position;

[0025] S3: Establish a working channel, insert the guide sheath, and use the imaging marker at its distal end to confirm that the tip of the guide sheath has been accurately placed in the predetermined position within the target hepatic vein. Then, withdraw the guide. At this point, the guide sheath has established a stable intravascular working channel.

[0026] S4: Coaxial cutting needle preparation and positioning. The disposable coaxial cutting needle is pre-installed into the housing. Under the imaging equipment, the direction of the guide sheath is finely adjusted by observing the annular metal contrast mark on the tip of the disposable coaxial cutting needle so that the bevel of the needle tip faces the target liver parenchyma.

[0027] S5: Firing for sampling. The operator presses the firing button to trigger the firing mechanism inside the housing, driving the disposable coaxial cutting needle to eject forward from the guide sheath at high speed and in a short distance. The oblique cutting edge and double oblique cutting surface of the needle tip pierce the target liver tissue. Under compression, the liver tissue pushes open the one-way elastic valve and enters the tissue groove. At the same time, the spiral guide pattern generates a guiding effect during the movement of the needle body, pushing the residue in the groove to the bottom of the groove.

[0028] S6: Acquire and seal the sample. After firing, retract the disposable coaxial cutting needle. During the retraction process, the tissue groove filled with tissue is smoothly withdrawn due to the micron-level smooth coating at the groove opening, which reduces adhesion. The one-way elastic valve automatically closes under the filling of tissue sample and the negative pressure of retraction, effectively sealing the tail end of the groove and preventing sample loss and backflow contamination of blood and tissue fluid.

[0029] S7: Sample processing and device removal. The disposable coaxial cutting needle is removed from the housing and a complete liver tissue sample is obtained from its tissue groove. The biopsy is now complete.

[0030] Compared with existing technologies, the present invention provides a transjugular liver biopsy component and its method of use. On the one hand, by integrating a unidirectional elastic valve and spiral guide lines within the tissue groove of a disposable coaxial cutting needle, the automatic opening and closing of the valve achieves unidirectional flow and sealing of the tissue groove, effectively preventing venous blood backflow from contaminating the sample and preventing tissue block loss. On the other hand, by applying a specific functional coating and imaging structure to the needle tip and needle body surface, the puncture and cutting performance, as well as the visibility and directional identification under imaging, are optimized. This solves the key problems of poor sample quality, large blind spots, and safety concerns associated with biopsies via the transjugular vein approach. In particular, it provides a reliable interventional solution for high-risk patients with coagulation disorders, allowing for the acquisition of sufficient, complete, and clean strip-shaped liver tissue samples in a single procedure. Specific technical effects include the following:

[0031] 1. The one-way elastic valve at the end of the tissue groove opens under pressure when the needle is inserted into the liver tissue, allowing the tissue to enter the groove smoothly. It closes automatically when the sample fills the groove and the needle is withdrawn, forming a physical seal. This effectively prevents hepatic venous blood from flowing back into the groove, diluting and contaminating the sample. It also prevents the captured soft liver tissue from falling off or breaking during withdrawal, ensuring that a long and complete strip of tissue sample is obtained in one go. This improves the success rate of a single puncture and reduces the risk of vascular damage caused by repeated operations.

[0032] 2. The needle tip adopts a design combining a slanted blade with an axe-shaped double-bevel cutting surface, and is equipped with a ring-shaped metal imaging mark. This not only provides clear and specific indication of the needle tip position and angle under ultrasound, X-ray or CT, but also facilitates the operator to accurately adjust the puncture direction and achieve precise targeting of the target area.

[0033] 3. The micron-level smooth coating (such as PTFE or diamond-like carbon film) covering the tissue groove and inner wall, and the low-adsorption, tumor-cell-repellent coating (such as diamond-like carbon film or heparin composite coating) covering the outer surface of the needle, greatly reduce the adhesion of liver tissue cells (especially potential tumor cells) to the instrument surface. This minimizes the potential risk of tumor cell implantation or dissemination within the needle tract due to repeated insertion and removal of the instrument. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0035] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0036] Figure 2 This is a schematic diagram of the guiding sheath and coaxial cutting needle in Embodiment 1 of the present invention;

[0037] Figure 3 This is a schematic diagram of the spiral guide pattern in Embodiment 2 of the present invention;

[0038] Figure 4 This is a flowchart illustrating the usage method of the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Shell; 2. Guiding sheath; 3. Coaxial cutting needle; 4. Firing key; 5. Tissue groove; 6. One-way elastic valve; 7. Spiral guide groove. Detailed Implementation

[0041] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0042] As attached Figure 1 To be continued Figure 2 As shown:

[0043] Example 1:

[0044] This invention provides a transcervical transhepatic biopsy assembly. The biopsy assembly is configured to work with an image-guided device to establish a working channel in the hepatic vein via the jugular vein and perform tissue cutting and sampling. The biopsy assembly includes a housing 1, a channel establishment module disposed at the proximal end of the housing 1 for establishing an intravascular access, and a tissue cutting module disposed within the channel establishment module for obtaining tissue samples from the target liver parenchyma.

[0045] 1. In one embodiment of the present invention, the channel establishment module includes a guide sheath 2 and a guide member, wherein the guide member is an elongated member that can be inserted into the internal channel of the guide sheath 2, and the guide sheath 2 is a tubular member with a development mark at its distal end.

[0046] 2. In one embodiment of the present invention, the tissue cutting module is a disposable coaxial cutting needle 3, the needle core of which is provided with a tissue groove 5, and the tail end of the tissue groove 5 is provided with a one-way elastic valve 6; the tip of the disposable coaxial cutting needle 3 is a beveled blade combined with a double beveled cutting surface and is provided with an annular metal imaging mark, and the outer surface of the disposable coaxial cutting needle 3 is coated with a low-absorption tumor cell-reducing coating; the one-way elastic valve 6 is a silicone duckbill valve, which consists of two flexible leaflets arranged in a Y shape and embedded in the tissue groove 5 at the tail end of the needle core. The one-way elastic valve 6 is closed in its natural state, opens under tissue compression to allow tissue to enter the groove, and automatically closes after the tissue fills the groove to prevent backflow of blood or tissue fluid.

[0047] 3. In one embodiment of the present invention, a firing mechanism for driving the coaxial cutting needle 3 to pop forward relative to the guide sheath 2 is provided on the inner side of the housing 1, and a firing key 4 for triggering the firing mechanism is provided on the outer side of the housing 1.

[0048] 4. In one embodiment of the present invention, the low-adsorption tumor cell-repellent coating is a diamond-like carbon film or a heparin composite coating, which covers the outer surface of the needle core of the disposable coaxial cutting needle 3 (including the exposed section of the needle core and the section in contact with the outer sheath).

[0049] 5. In one embodiment of the present invention, the annular metal imaging mark is a platinum-iridium alloy ring or a gold-plated layer with a width of 0.5 to 1.0 mm, and the position and angle of the needle tip are clearly visible under ultrasound or X-ray / CT.

[0050] 6. In one embodiment of the present invention, the angle between the beveled cutting edge of the needle tip and the axis of the needle body is 30 to 45°, and the double beveled cutting surface is axe-shaped to prevent snagging on tissue.

[0051] Working Principle: Example 1 provides a transcervical and transhepatic biopsy component. With the assistance of an image-guided device, a stable intravascular working channel can be constructed between the jugular vein and the target hepatic vein via a channel establishment module. The location is visualized using a contrast marker at the distal end of the guide sheath 2. The tissue cutting module uses a disposable coaxial cutting needle 3 with a beveled edge and double-beveled cutting surface at the tip, and an annular metal contrast marker for clear guidance and identification during the puncture process. The outer surface of the needle is coated with a low-absorption, tumor-reducing coating to minimize tissue adhesion and the risk of potential cell implantation. The tissue groove 5 on the needle core has a one-way elastic valve 6 at its tail end. This valve closes naturally and opens under tissue compression to allow liver tissue to enter the groove. Once the groove is full, it automatically closes to form a physical seal, preventing venous blood backflow and sample contamination during sampling, and facilitating the acquisition of relatively complete strips of liver tissue. The component uses a firing mechanism inside the housing 1 to drive the coaxial cutting needle 3 to pop forward relative to the guide sheath 2 to complete the cutting when triggered by the firing key 4 on the outside of the housing 1. The action is consistent and easy to operate, thus achieving the goal of safely and efficiently obtaining high-quality liver tissue samples via the jugular vein route.

[0052] As attached Figure 1 Appendix Figure 3 As shown:

[0053] Example 2:

[0054] This embodiment is basically the same as the previous embodiment, except that the inner wall of the tissue groove 5 is provided with a spiral guide pattern 7 and the edge of the groove is provided with a chamfered surface and covered with a micron-level smooth coating. The spiral guide pattern 7 is a shallow-pitch spiral groove with a pitch of 0.3 to 0.8 mm and a depth of 0.05 to 0.1 mm. The direction of the shallow-pitch spiral groove is consistent with the needle core ejection / retraction movement, which is used to generate eddies during the movement to push residual blood and small tissue blocks to the bottom of the groove.

[0055] 1. In one embodiment of the present invention, the micron-level smooth coating is a polytetrafluoroethylene or diamond-like carbon film with a surface roughness Ra≤0.1μm, which covers the opening and inner wall of the tissue groove to reduce tissue adhesion.

[0056] Working Principle: Due to the soft texture of liver tissue and the continuous blood supply within the hepatic veins, simple physical sealing may still affect the complete removal and cleanliness of the sample during the sampling and withdrawal process due to adhesion between the tissue and the groove wall or interference from residues within the groove. Therefore, in Example 2, the tissue cutting module is further functionally enhanced based on Example 1. A spiral guide pattern 7 with specific parameters is added to the inner wall of the tissue groove 5, and the groove opening edge is beveled and covered with a micron-level smooth coating. This combined design allows the spiral pattern to guide the generation of directional vortices when the needle core is ejected to pierce the tissue and during sampling and withdrawal, actively pushing any trace amounts of residual blood and loose debris within the groove towards the bottom (valve end), thus achieving a cleaning and guiding effect. Simultaneously, the ultra-smooth groove opening and inner wall greatly reduce the adhesion force of liver tissue cells, allowing the completely cut strip tissue sample to slide out of the tissue groove 5 more smoothly and without damage. These two improvements, in conjunction with the existing one-way valve sealing mechanism, ensure that the final sample obtained is not only complete and sufficient, but also cleaner, further improving the quality of biopsy pathological diagnosis and the one-time success rate.

[0057] As attached Figure 4 As shown:

[0058] In conjunction with Embodiments 1 and 2 above, the present invention also provides a method for using the transcervical transhepatic biopsy component, comprising the following steps:

[0059] S1: Preoperative preparation and puncture path planning. Under the monitoring of image-guided equipment (such as ultrasound, DSA or CT), assess and plan the puncture path from the jugular vein to the target hepatic vein, and determine the target area of ​​the liver parenchyma.

[0060] S2: Guide positioning, insert the guide into the target hepatic vein branch via the internal jugular vein and confirm the position;

[0061] S3: Establish a working channel, insert the guide sheath 2, and use the imaging marker at its distal end to confirm that the tip of the guide sheath 2 has been accurately placed in the predetermined position in the target hepatic vein. Then withdraw the guide, at which point the guide sheath 2 has established a stable intravascular working channel.

[0062] S4: Preparation and positioning of coaxial cutting needle 3. The disposable coaxial cutting needle 3 is pre-installed into the housing 1. Under the imaging equipment, by observing the annular metal imaging mark at the tip of the disposable coaxial cutting needle 3, the direction of the guide sheath 2 is finely adjusted so that the bevel of its tip faces the target liver parenchyma.

[0063] S5: Firing for sampling. The operator presses the firing key 4 to trigger the firing mechanism inside the housing 1, driving the disposable coaxial cutting needle 3 to eject forward from the guide sheath 2 at high speed and short distance. The oblique cutting edge and double oblique cutting surface of the needle tip pierce the target liver tissue. Under compression, the liver tissue pushes open the one-way elastic valve 6 and enters the tissue groove 5. At the same time, the spiral guide pattern 7 generates a guiding effect during the movement of the needle body, pushing the residue in the groove to the bottom of the groove.

[0064] S6: After obtaining and sealing the sample and completing the firing, the disposable coaxial cutting needle 3 is withdrawn. During the withdrawal process, the tissue groove 5 filled with tissue is smoothly withdrawn due to the micron-level smooth coating at the groove opening, which reduces adhesion. The one-way elastic valve 6 automatically closes under the filling of tissue sample and the negative pressure of withdrawal, effectively sealing the tail end of the groove and preventing sample loss and backflow contamination of blood and tissue fluid.

[0065] S7: Sample processing and device removal. The disposable coaxial cutting needle 3 is removed from the housing 1, and a complete liver tissue sample is obtained from its tissue groove 5. At this time, the biopsy is completed.

[0066] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A transjugular transhepatic biopsy assembly, the biopsy assembly being configured to cooperate with an image-guided device to establish a working channel in the hepatic vein via the jugular vein and perform tissue cutting and sampling, the biopsy assembly comprising a housing (1), a channel establishment module disposed at the proximal end of the housing (1) for establishing an intravascular access, and a tissue cutting module disposed within the channel establishment module for obtaining tissue samples from the target liver parenchyma, characterized in that: The channel establishment module includes a guide sheath (2) and a guide, wherein the guide is a slender member that can be inserted into the internal channel of the guide sheath (2), and the guide sheath (2) is a tubular member with a development mark at its distal end; The tissue cutting module is a disposable coaxial cutting needle (3), which has a tissue groove (5) on its needle core. The tail end of the tissue groove (5) is provided with a one-way elastic valve (6). The inner wall of the tissue groove (5) is provided with a spiral guide pattern (7) and the edge of the groove is provided with a chamfered surface and covered with a micron-level smooth coating. The inner side of the housing (1) is provided with a firing mechanism for driving the coaxial cutting needle (3) to pop forward relative to the guide sheath (2), and the outer side of the housing (1) is provided with a firing key (4) for triggering the firing mechanism.

2. The transcervical transhepatic biopsy assembly according to claim 1, characterized in that, The tip of the disposable coaxial cutting needle (3) is a beveled blade combined with a double beveled cutting surface and is provided with an annular metal imaging mark. The outer surface of the disposable coaxial cutting needle (3) is covered with a low-adsorption tumor cell-reducing coating.

3. The transcervical transhepatic biopsy assembly according to claim 1, characterized in that, The unidirectional elastic valve (6) is a silicone duckbill valve, which consists of two flexible leaflets arranged in a Y shape and embedded in the tissue groove (5) at the end of the needle core.

4. The transcervical transhepatic biopsy assembly according to claim 1, characterized in that, The spiral guide pattern (7) is a shallow pitch spiral groove with a pitch of 0.3 to 0.8 mm and a depth of 0.05 to 0.1 mm. The direction of the shallow pitch spiral groove is consistent with the needle core ejection / retraction movement.

5. The transcervical transhepatic biopsy assembly according to claim 1, characterized in that, The micron-level smooth coating is polytetrafluoroethylene or diamond-like carbon film.

6. The transcervical transhepatic biopsy assembly according to claim 2, characterized in that, The low-adsorption antitumor cell coating is a diamond-like carbon film or a heparin composite coating.

7. A transcervical transhepatic biopsy assembly according to claim 2, characterized in that, The annular metal development mark is a platinum-iridium alloy ring or a gold-plated layer, with a width of 0.5–1.0 mm.

8. A transcervical transhepatic biopsy assembly according to claim 2, characterized in that, The angle between the oblique cutting edge of the needle tip and the axis of the needle body of the disposable coaxial cutting needle (3) is 30-45°, and the double oblique cutting surface is axe-shaped.

9. A method of using the transcervical transhepatic biopsy assembly as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: Preoperative preparation and puncture path planning. Under the monitoring of image-guided equipment, assess and plan the puncture path from the jugular vein to the target hepatic vein, and determine the target area of ​​the liver parenchyma. S2: Guide positioning, insert the guide into the target hepatic vein branch via the internal jugular vein and confirm the position; S3: Establish a working channel, insert the guide sheath (2), and use the imaging marker at its distal end to confirm that the tip of the guide sheath (2) has been accurately placed in the predetermined position in the target hepatic vein. Then remove the guide. At this time, the guide sheath (2) establishes a stable intravascular working channel. S4: Preparation and positioning of coaxial cutting needle (3): The disposable coaxial cutting needle (3) is pre-installed into the housing (1). Under the imaging equipment, the direction of the guide sheath (2) is finely adjusted by observing the annular metal imaging mark on the tip of the disposable coaxial cutting needle (3) so that the bevel of its tip faces the target liver parenchyma. S5: Firing for sampling. The operator presses the firing key (4) to trigger the firing mechanism inside the housing (1), driving the disposable coaxial cutting needle (3) to spring forward from the guide sheath (2) at high speed and short distance. The oblique cutting edge and double oblique cutting surface of the needle tip pierce the target liver tissue. The liver tissue pushes open the one-way elastic valve (6) under compression and enters the tissue groove (5). At the same time, the spiral guide pattern (7) generates a guiding effect during the movement of the needle body, pushing the residue in the groove to the bottom of the groove. S6: After obtaining and sealing the sample and completing the firing, retract the disposable coaxial cutting needle (3). During the retraction process, the tissue groove (5) filled with tissue is smoothly withdrawn due to the micron-level smooth coating at the groove opening, which reduces adhesion. The one-way elastic valve (6) automatically closes under the filling of tissue sample and the negative pressure of retraction, effectively sealing the tail end of the groove and preventing sample loss and backflow contamination of blood and tissue fluid. S7: Sample processing and device removal. The disposable coaxial cutting needle (3) is removed from the housing (1) and a complete liver tissue sample is obtained from its tissue groove (5). At this time, the biopsy is completed.

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