Electrocoagulation system for neurointerventional therapy

Abstract

This application relates to an electrocoagulation system for neurointerventional therapy. The electrocoagulation system is used in conjunction with a flow-directing stent to perform aneurysm embolization, comprising: an electrocoagulation guidewire, which is a slender, flexible conductor, with its proximal end connected to a current generating device; and a guidewire shell, which is a slender, flexible, hollow insulator for housing the electrocoagulation guidewire. At least a portion of the distal end of the guidewire shell is configured to pass through at least a portion of the mesh of a flow-directing stent already placed in the blood vessel and enter the aneurysm body. The electrocoagulation guidewire is slidably disposed within the guidewire shell, and its distal end is configured to extend from the distal end of the guidewire shell to enter the aneurysm body. Electrocoagulation technology, as an adjunct therapy to flow-directing stents, generates a local thrombus-forming effect after the flow-directing stent is placed, enhancing the flow-directing stent's effect in promoting thrombus formation within the aneurysm, thus enabling the two to work synergistically during the treatment process.

Description

Technical Field

[0001] This application relates to the field of medical devices, and more particularly to an electrocoagulation system for neurointerventional therapy. Background Technology

[0002] Intracranial aneurysms are common cerebrovascular diseases in neurosurgery, often referred to as intracranial "time bombs" due to their potential rupture risk. Essentially, they are weak points in the walls of intracranial arteries that bulge abnormally outward under the influence of blood flow and blood pressure, resembling a tumor in shape, hence the name aneurysm. Intracranial aneurysms are not true neoplastic lesions, but once ruptured, the condition is critical, causing symptoms such as severe headache, nausea, vomiting, convulsions, and altered consciousness, and even death. Intracranial aneurysms have high mortality and disability rates; therefore, early diagnosis and timely treatment are of significant clinical importance in improving patients' survival rates and quality of life.

[0003] Currently, treatment methods for intracranial aneurysms mainly fall into two categories: surgical clipping and endovascular interventional therapy. Surgical clipping requires cutting open the skull and separating brain tissue to reach the aneurysm, resulting in significant trauma, slow recovery, and the risk of postoperative complications such as epilepsy. In contrast, endovascular interventional therapy, due to its advantages of minimal trauma, rapid recovery, and less patient discomfort, has become the preferred treatment option for an increasing number of patients. The main technical approaches in endovascular interventional therapy include interventional embolization and the implantation of flow diverting devices.

[0004] Interventional embolization of aneurysms involves inserting a material into the aneurysm through a blood vessel, filling it with a filler material to prevent blood flow from entering the cerebral aneurysm, thus separating the aneurysm from the blood flow. This interventional procedure is minimally invasive, with minimal trauma, rapid recovery, and good results. The most commonly used material for interventional embolization is a coil, a platinum-plated metal wire that is flexible. During the embolization procedure, a microcatheter is inserted into the aneurysm cavity, and then a pusher is used to push the coil into the aneurysm cavity through the microcatheter. Once the coil is stable within the aneurysm cavity, the connection between the pusher and the coil is released, and the pusher is withdrawn from the microcatheter. When blood flows into the aneurysm, many small vortices form at the edge of the aneurysm wall, like a river channel, slowing down the blood flow. Inserting a coil into the aneurysm artificially amplifies this slowing of blood flow, causing it to slow down significantly and almost stop within a short time, forming a thrombus. This significantly reduces the pressure within the aneurysm, greatly minimizing the possibility of rupture.

[0005] Neurosurgeons first need to determine the location, size, and shape of the aneurysm through arteriography, adjusting the position of the catheter and equipment to fully expose the aneurysm to the surgeon's view. Then, guided by a guidewire, a finer microcatheter is inserted into the aneurysm. Once inside the aneurysm, a very soft metallic material called a "coil" is inserted through the microcatheter to seal the aneurysm or cause thrombosis, preventing blood from entering and thus curing the aneurysm. Sometimes, the aneurysm's "neck" is small, called a narrow-necked aneurysm, which can be cured by simple coil embolization; other times, the "neck" is wide, and the inserted coil is prone to slipping out. In this case, a stent is needed to support the aneurysm opening and prevent the coil from entering the blood vessel. In some situations, the blood vessels surrounding the aneurysm are very complex, or the aneurysm is large, and direct embolization of the aneurysm may affect important blood vessels. In these cases, a "bypass" surgery may be needed, where the surgeon artificially connects the blood vessels around the aneurysm so that the embolization does not affect the brain's blood supply.

[0006] In 1991, Guglielmi developed and used electrolytic platinum microcoils (GDC), which has since become an important method for treating intracranial aneurysms. The distal end of the GDC is a platinum coil connected to a stainless steel guidewire, allowing direct insertion into the aneurysm. When direct current is applied, the coil attracts negatively charged blood components (red blood cells, white blood cells, platelets, etc.), causing electrocoagulation and forming a thrombus within the aneurysm. Simultaneously, the connection between the coil and the stainless steel guidewire dissolves due to electrolysis, leaving the coil detached and remaining within the aneurysm. The GDC coil is extremely flexible, exhibiting good compliance in advancing and retreating within the aneurysm; its placement can be adjusted if unsatisfactory, and it is less likely to cause occlusion of the parent artery.

[0007] Besides coil embolization, flow-directing mesh stenting has become an important method for treating intracranial aneurysms, especially large and complex ones, both internationally and domestically. Flow-directing mesh stents (also known as mesh stents or flow-directing stents) cover the neck of the aneurysm with a high-density braided mesh, diverting the pulsating blood flow from the parent artery to distal normal vessels. This significantly reduces the velocity and flow rate of blood entering the aneurysm sac, inducing blood stasis and thrombus formation within the sac. Simultaneously, it guides the growth of vascular endothelial cells on the stent surface, ultimately achieving complete occlusion of the aneurysm and vascular reconstruction. Compared to coil embolization, mesh stenting offers advantages such as a high cure rate and low recurrence rate, making it particularly suitable for complex cases such as wide-necked aneurysms, giant aneurysms, and fusiform aneurysms.

[0008] Based on device type, the global flow diversion device market is segmented into PED (Pipeline Embolization Device), p64, Silk Flow, Surpass Flow, and FRED flow diversion devices. The PED segment holds the largest market share and is expected to maintain its dominance throughout the study period. Its wide range of applications and higher efficiency enable it to achieve the largest market share. PEDs are suitable for patients aged 22 years and older for the treatment of small to medium-sized cerebral aneurysms (<2 mm in diameter) in the fornix neck, as well as various types of aneurysms such as saccular aneurysms, fusiform aneurysms, and carotid aneurysms with diameters between 2 mm and 5 mm.

[0009] In 2023, the size segment larger than 5 mm dominated the market. Flow diverters with a diameter greater than 5 mm are capable of effectively treating intracranial aneurysms larger than 10 mm. Therefore, these flow diverters larger than 5 mm are typically used for placement in large vessels exhibiting a high occlusion rate. Their wide range of applications includes managing large-necked and wide-mouth intracranial aneurysms, especially since most ruptured aneurysms are larger than 10 mm in diameter. Thus, flow diverters larger than 5 mm are best suited for placement in large arteries, resulting in more stable aneurysm closure rates and driving growth in this segment in the coming years.

[0010] Devices with a diameter between 3 and 4 mm feature 72 braided threads, providing a higher porosity. A variety of products with a diameter of 3 to 4 mm are available on the market, such as SURPASS, p64, and FRED Pipeline flow diverters. Flow diverters with a diameter of 3-4 mm are more suitable for small vessels and have a greater chance of effectively redirecting blood flow at the desired location. This means they can treat a wider range of aneurysms and malformations. Additionally, the smaller metal coverage of 3-4 mm flow diverters reduces the risk of thrombotic events and the need for antiplatelet therapy, making the treatment process safer and more efficient.

[0011] However, dense-mesh stents still have some technical limitations in clinical applications. Although flow-directing stents can promote thrombus formation within aneurysms by changing the direction of blood flow, the thrombus formation rate induced by flow-directing stents within the aneurysm sac is relatively slow. Especially for some complex aneurysms (such as large aneurysms or giant aneurysms), relying solely on the flow-directing effect of dense-mesh stents, thrombus formation can take up to several months, and in some cases, complete thrombus formation may not occur for a long time, leading to delayed or non-healing of the aneurysm. In severe cases, it may even require re-implantation of flow-directing stents for treatment.

[0012] The paper "The role of Pipeline combined with coils in the treatment of large and giant unruptured aneurysms of the internal carotid artery" explores the role of Pipeline (PED) combined with coil embolization in the treatment of large and giant aneurysms of the internal carotid artery. The results show that using PED combined with coils to fill the aneurysm cavity can reduce the incidence of aneurysm residue, but may have a higher risk of thrombotic events.

[0013] Furthermore, electrocoagulation, as a physical means to promote thrombus formation, has been explored in the treatment of aneurysms. Electrocoagulation is a medical technique that uses electric current to act on vascular tissue to achieve target vessel occlusion. Its core mechanism is based on the thermal and electrochemical effects of electric current. Direct current or alternating current is applied through a guidewire or electrode, attracting negatively charged blood cells (such as platelets and erythrocytes) to accumulate around the anode, thus forming a local thrombus. This process, through an electrochemical reaction, directly promotes the formation of thrombi within the blood vessel, ultimately achieving occlusion of the artery or aneurysm. During endovascular treatment, the tip of the microguidewire is used as the anode. When current passes through, a thrombus forms within the aneurysm or the parent artery. Post-operative angiography can confirm whether the target site has been completely occluded. Compared to coil embolization, electrocoagulation shows significant advantages in treating aneurysms that cannot be reached by microcatheters and can be used to treat small aneurysms or perforating aneurysms that cannot be accessed by microcatheters.

[0014] However, existing electrocoagulation techniques have significant drawbacks: First, for larger aneurysms, the thrombus formed by electrocoagulation cannot remain stable under continuous blood flow impact, leading to a high recurrence rate; second, if a conventional guidewire comes into contact with the metal stent when passing through the mesh of a dense stent, it can cause a short circuit, making the entire stent electrified, which may lead to serious complications such as in-stent thrombosis or even vascular occlusion; in addition, existing electrocoagulation guidewires lack structural optimization for passing through the mesh, resulting in poor operational controllability, unstable thrombus formation, and a high recurrence rate.

[0015] Therefore, how to effectively combine electrocoagulation technology with dense mesh stents to both leverage the advantages of electrocoagulation in accelerating thrombus formation and avoid risks such as short circuits has become a pressing technical problem to be solved in this field. Currently, there is no electrocoagulation guidewire specifically designed for passing through the mesh of a dense mesh stent, and even less of a complete technical solution to form a synergistic treatment system with dense mesh stents. Summary of the Invention

[0016] To address the shortcomings of existing dense-mesh stent treatments, such as slow or incomplete thrombus formation within the aneurysm sac, difficulties in assisted tamponade procedures, and the risk of short circuits when using existing electrocoagulation techniques in conjunction with dense-mesh stents, this application provides an electrocoagulation system specifically designed for passing through the mesh of a dense-mesh stent. The technical solution of this application aims to at least partially solve the following technical problems: how to ensure the electrocoagulation guidewire can safely pass through the tiny mesh of the dense-mesh stent while avoiding short circuits caused by contact between the guidewire and the metal stent; how to control the length of the conductive portion of the electrocoagulation guidewire entering the aneurysm sac to accommodate aneurysms of different sizes; and how to provide accurate imaging guidance for the operator.

[0017] This application provides an electrocoagulation system for neurointerventional therapy, used in conjunction with a flow-directing stent to perform aneurysm embolization. The system comprises: an electrocoagulation guidewire, which is a slender, flexible conductor, with its proximal end for connection to a current generating device; and a guidewire shell, which is a slender, flexible, hollow insulator for housing the electrocoagulation guidewire. At least a portion of the distal end of the guidewire shell is configured to pass through at least a portion of the mesh of a flow-directing stent already placed within a blood vessel to enter the aneurysm body. The electrocoagulation guidewire is slidably disposed within the guidewire shell, and the distal end of the electrocoagulation guidewire is configured to extend from the distal end of the guidewire shell to enter the aneurysm body.

[0018] In some embodiments, the distal end of the guidewire housing is tapered, or its cross-sectional area gradually decreases toward the distal end.

[0019] In some embodiments, the head of the distal end of the guidewire housing is configured to remain closed when not subjected to the thrust of the internal electrocoagulation guidewire, and to open outward when subjected to the thrust of the internal electrocoagulation guidewire to allow the distal end of the electrocoagulation guidewire to extend.

[0020] In some embodiments, the distal head of the guidewire housing is configured to consist of a plurality of radially expandable petal-shaped components.

[0021] In some embodiments, the distal end of the guidewire housing is provided with a diameter abrupt change portion, the outer diameter of the distal end of the diameter abrupt change portion being smaller than the outer diameter of its proximal end, which is used to form an abutment with the edge of the mesh when the guidewire housing passes through the mesh of the blood flow guiding stent, so as to limit the distal end of the guidewire housing from going too deep.

[0022] In some embodiments, the diameter abrupt change portion is provided with a development mark.

[0023] In some embodiments, the length of the electrocoagulation wire is longer than the length of the wire shell.

[0024] In some embodiments, the proximal end of the electrocoagulation guidewire is provided with a scale to indicate the extension length of the distal end of the electrocoagulation guidewire relative to the distal end of the guidewire housing.

[0025] In some embodiments, the distal end of the electrocoagulation wire is made of a high-resistivity material.

[0026] In some embodiments, a microcatheter is also included for delivering a guidewire housing and an electrocoagulation guidewire located therein to the vicinity of a flow guidance stent.

[0027] The technical solution of this application is applicable to the use of electrocoagulation technology as supplementary treatment for aneurysms with residual blood flow or some refractory aneurysms after the placement of a flow-directing stent. The local thrombosis effect generated by electrocoagulation technology can enhance the effect of the flow-directing stent in promoting thrombus formation within the aneurysm. Through this technical solution, the distal end of the electrocoagulation guidewire is electrically heated within the aneurysm, actively promoting rapid coagulation and thrombosis of the blood within the aneurysm. This solves the problem of slow thrombus formation relying on natural blood flow stagnation in existing technologies, reducing the risk of secondary aneurysm recurrence. Multiple structural designs ensure operational safety: the guidewire tip is tapered, facilitating passage through the dense mesh stent; the diameter abrupt change forms a mechanical limit with the stent mesh, preventing the guidewire from penetrating excessively and touching the aneurysm wall; the guidewire shell is an insulator, ensuring insulation from the dense mesh stent and preventing abnormal thrombosis of the blood within the vessel. A contrast marker is placed at the diameter abrupt change, allowing the operator to monitor the guidewire position in real time under imaging, ensuring it accurately reaches the predetermined position without contacting the aneurysm wall. The graduated design at the proximal end of the electrocoagulation guidewire allows the operator to precisely control the guidewire extension length according to the size of the aneurysm, enabling individualized and precise treatment. Compared to simply relying on a dense mesh stent and waiting for the thrombus to form naturally, this system can accelerate the occlusion process of the aneurysm sac; compared to simple electrocoagulation therapy, this system avoids the problems of thrombus instability and high recurrence rate; compared to auxiliary coil tamponade, this system is simpler to operate, lower in cost, and does not interfere with stent visualization. Attached Figure Description

[0028] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application are illustrated by way of example and not limitation, and the same or corresponding reference numerals denote the same or corresponding parts, wherein:

[0029] Figure 1 A schematic diagram of an electrocoagulation system according to an embodiment of this application is shown; Figure 2 A schematic diagram of an electrocoagulation system according to an embodiment of this application is shown; Figure 3 A schematic diagram of an electrocoagulation system according to an embodiment of this application is shown. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] It should be understood that the terms "first," "second," "third," and "fourth," etc., used in the claims, specification, and drawings of this application are used to distinguish different objects, rather than to describe a specific order. The terms "comprising" and "including" used in the specification and claims of this application indicate the presence of the described features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof.

[0032] It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application. As used in this specification and claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this specification and claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations.

[0033] As used in this specification and claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0034] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0035] Example 1: Basic Structure of an Electrocoagulation System like Figure 1 As shown, this embodiment provides an electrocoagulation system for neurointerventional therapy, including an electrocoagulation guidewire 1 and a guidewire shell 2.

[0036] The electrocoagulation wire 1 is a thin, flexible conductive metal wire, the proximal end of which (left end in the figure) is used to connect to a current generating device (not shown in the figure). The distal end of the electrocoagulation wire 1 (right end in the figure) is preferably made of a high-resistivity material, with a resistivity higher than that of the proximal end, and is used to generate heat when energized, thereby promoting rapid thrombosis of the blood within the aneurysm 5.

[0037] Although the electrocoagulation guidewire in this embodiment has a uniform diameter, those skilled in the art will know that the diameter of the electrocoagulation guidewire can be gradual, for example, gradually decreasing in diameter near the distal end. This gradual diameter design can make the distal end of the guidewire more flexible. The gradual change can be linear, step-like, or curved.

[0038] The guidewire housing 2 is a slender, flexible, hollow insulator used to house the electrocoagulation guidewire 1. The inner diameter of the guidewire housing 2 is slightly larger than the diameter of the electrocoagulation guidewire 1. At least a portion of the distal end (right end in the illustration) of the guidewire housing 2 is configured to pass through at least a portion of the mesh of the blood flow guiding stent 6 already placed in the blood vessel into the aneurysm 5.

[0039] The electrocoagulation guidewire 1 is slidably disposed within the guidewire housing 2. Preferably, the length of the electrocoagulation guidewire 1 is longer than the length of the guidewire housing 2, ensuring that the distal end of the electrocoagulation guidewire 1 can extend from the distal end of the guidewire housing 2 to enter the aneurysm 5.

[0040] After energization, the distal end of the electrocoagulation guidewire 1 generates thermal and electrochemical effects within the aneurysm 5, actively promoting blood coagulation and thrombosis, significantly shortening the time required for thrombus formation dependent on natural blood flow stagnation. The rapidly formed stable thrombus effectively occludes the aneurysm cavity, and even if a small amount of blood seeps in through the stent mesh, it is difficult to flush away the already formed thrombus, thus greatly reducing the risk of secondary aneurysm recurrence.

[0041] Preferably, the proximal end of the electrocoagulation guidewire 1 is provided with a scale L1 to indicate the extension length of the distal end of the electrocoagulation guidewire 1 relative to the distal end of the guidewire housing 2. In use, using the proximal end of the guidewire housing 2 (left end in the illustration) as a reference point, the scale value exposed on the proximal end of the electrocoagulation guidewire 1 can be read to determine the extension length of the distal end of the electrocoagulation guidewire 1. The scale design at the proximal end of the electrocoagulation guidewire 1 allows the operator to precisely control the extension length of the electrocoagulation guidewire 1 according to the size of the aneurysm, achieving individualized and precise treatment.

[0042] Example 2: Structural Design of the Distal End of the Guidewire Sheath like Figure 2 and Figure 3 As shown, this embodiment further defines the distal structure of the guidewire shell 2 based on embodiment 1.

[0043] The distal head 8 of the guidewire housing 2 is tapered, or its cross-sectional area gradually decreases towards the distal end. The tapered head design allows the guidewire housing 2 to pass smoothly through the mesh of the blood flow guiding stent 6, reducing pushing resistance.

[0044] Preferably, the distal head 8 of the guidewire housing 2 is configured to remain closed when not subjected to the thrust of the internal electrocoagulation guidewire 1; and to open outward when subjected to the thrust of the internal electrocoagulation guidewire 1, allowing the distal end of the electrocoagulation guidewire 1 to extend. The head 8 remaining closed when not subjected to thrust avoids sharp-edge damage to the tumor wall.

[0045] One implementation involves a conical tip composed of multiple radially expandable petal-shaped components. These petal-shaped components are naturally closed, forming a smooth conical tip. When the electrocoagulation wire 1 is pushed forward, its distal end pushes against the inner wall of the petal-shaped components, causing them to open outwards, forming a channel for the electrocoagulation wire 1 to pass through. When the electrocoagulation wire 1 is retracted, the petal-shaped components return to their closed state due to their own elasticity. This design ensures that it cannot be opened by external force, but can be opened by pushing it from the inside with the electrocoagulation wire 1.

[0046] The guidewire housing 2 is made entirely of insulating material, ensuring electrical insulation between the electrocoagulation guidewire 1 and the blood flow guiding stent 6.

[0047] Preferably, the distal end of the guidewire housing 2 is provided with a diameter abrupt change section, the outer diameter of the distal end of the diameter abrupt change section (right side in the figure) being smaller than the outer diameter of its proximal end (left side in the figure), forming a significant diameter step difference. In embodiments where a conical head is also provided, the diameter abrupt change section is located on the proximal side of the conical head end (left side in the figure). This diameter abrupt change section is used to abut against the edge of the mesh (which has a certain degree of elasticity) of the blood flow guiding stent 6 when the diameter abrupt change section passes through it, thereby limiting the excessive penetration of the distal end of the guidewire housing 2. This design ensures that overshoot does not cause the tip of the guidewire housing 2 to contact the aneurysm wall when passing through the blood flow guiding stent 6, reducing the risk.

[0048] A contrast marker (MARK) is placed at the diameter abrupt change. This marker is clearly visible under medical imaging, allowing the operator to monitor the distal end of the guidewire shell in real time and determine its precise location through imaging. A contrast marker can also be placed at the tip of the tapered end, providing even more positional information. A contrast marker can also be placed at the distal end of the electrocoagulation guidewire to confirm its position within the tumor after extension.

[0049] It should be noted that the illustrations in the accompanying drawings are schematic representations intended to aid in understanding the technical solutions of this application and are not drawn strictly to scale. To clearly demonstrate the structural features of this application, the dimensions, proportions, and relative positions of the parts in the drawings may have been adjusted and should not be used to interpret or limit the scope of this application.

[0050] Example 3: How to use an electrocoagulation system This embodiment describes the specific operational steps for performing aneurysm embolization using the electrocoagulation system and flow diversion stent described in Embodiment 1 or 2.

[0051] The first step involves delivering the pre-shaped microcatheter to the aneurysm location. Because the microcatheter tip anastomoses with the parent artery, it automatically points towards the aneurysm neck. The microcatheter remains stationary. If the aneurysm neck is wide and the stent mesh is large, the microcatheter can be bypassed, or a guidewire-electrocoagulation guidewire assembly can be directly delivered to the vicinity of the stent and through the mesh using a guidewire.

[0052] The second step involves pushing the guidewire housing along the microcatheter lumen to the target location, namely the neck of the aneurysm. The distal end of the electrocoagulation guidewire remains inside the guidewire housing and does not extend beyond it.

[0053] The third step involves slowly advancing the guidewire shell. The conical tip of the guidewire shell passes through the mesh of the blood flow guiding stent already placed in the blood vessel and enters the aneurysm. Angiography can be performed simultaneously with the advancement of the guidewire shell.

[0054] The fourth step is to observe the positioning of the guidewire shell through contrast imaging.

[0055] Step 5: Once the guidewire shell's MARK point contacts the flow-directing stent, it must not be advanced further into the aneurysm to avoid touching the aneurysm wall. The operator may feel a significant increase in pushing resistance, or X-ray may show the contrast marker overlapping with the stent mesh. Confirm that the tapered tip of the guidewire shell has entered the aneurysm, but the main body of the guidewire shell is blocked by the stent mesh and has not entered the aneurysm. Confirm that the distal end of the guidewire shell has not contacted the aneurysm wall.

[0056] Step 6: Once in place, stop pushing the guidewire shell and keep it stationary relative to the flow-directing stent. In some cases, the guidewire shell can be delivered separately to the target location first, and then the electrocoagulation guidewire can be inserted. That is, first push the guidewire shell through the stent mesh into the aneurysm, keep it stationary once in place, and then insert the electrocoagulation guidewire from outside the body into the proximal end of the guidewire shell, push it to the distal end, and extend it out.

[0057] Step 7: Slowly advance the electrocoagulation guidewire until its tip extends beyond the distal end of the guidewire housing and enters the aneurysm. Determine the length of the guidewire tip entering the aneurysm based on its size and shape. Because neither the guidewire nor the guidewire housing undergoes significant elastic deformation along their length, the relative positions of their proximal and distal ends remain consistent. The guidewire length L3 entering the aneurysm is determined by the graduation L1 on the proximal end of the guidewire relative to the proximal end of the guidewire housing. For example, a 1mm decrease in L1 means a 1mm increase in L3.

[0058] Step 8: Connect a power generator to the proximal end of the electrocoagulation guidewire and apply voltage to cause the blood in the aneurysm to gradually coagulate and thrombosis.

[0059] Step 9: After electrocoagulation is complete, slowly retract the electrocoagulation guidewire until its distal end is completely retracted into the guidewire housing (the conical tip returns to a closed state). Then, remove the guidewire housing along with the electrocoagulation guidewire from the microcatheter. Finally, remove the microcatheter.

[0060] Example 4: Guide wire housing entry length specifications Depending on the aneurysm parameters, the length L2 of the guidewire shell entering the aneurysm can be set with different parameters for the physician to choose from. The physician can select the appropriate size guidewire shell based on the aneurysm size measured preoperatively.

[0061] Example 5: Electrocoagulation Conductor Wire Material The tip of the electrocoagulation guidewire is made of a high-resistivity metal material. When energized, the tip of the electrocoagulation guidewire heats up, promoting rapid thrombosis. The electrocoagulation guidewire can also be made of a material with uniform overall resistance, but the portion beyond the distal end that can enter the aneurysm remains insulated from the outside.

[0062] The electrocoagulation effect is confined to the aneurysm, preventing the current and heat from spreading to the parent artery and normal blood vessels. The distal end of the electrocoagulation guidewire, made of high-resistivity material, only heats locally when energized. The heat is concentrated and controllable, effectively promoting thrombus formation while avoiding thermal damage to surrounding normal tissues.

[0063] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An electrocoagulation system for neurointerventional therapy, used in conjunction with a flow diversion stent to perform aneurysm embolization, characterized in that, include: Electrocoagulation wire is a slender, flexible conductor whose proximal end is used to connect to a current generating device. The guidewire housing, a slender, flexible, hollow insulator, is used to house the electrocoagulation guidewire. At least a portion of the distal end of the guidewire housing is configured to pass through at least a portion of the mesh of the flow-guiding stent already placed within the blood vessel into the aneurysm body. The electrocoagulation guidewire is slidably disposed within the guidewire housing, and the distal end of the electrocoagulation guidewire is configured to extend from the distal end of the guidewire housing into the aneurysm body.

2. The electrocoagulation system according to claim 1, characterized in that, The distal end of the guidewire housing is tapered, or its cross-sectional area gradually decreases toward the distal end.

3. The electrocoagulation system according to claim 2, characterized in that, The distal head of the guidewire housing is configured to remain closed when not subjected to the thrust of the internal electrocoagulation guidewire, and to open outward when subjected to the thrust of the internal electrocoagulation guidewire to allow the distal end of the electrocoagulation guidewire to extend.

4. The electrocoagulation system according to claim 3, characterized in that, The distal head of the guidewire housing is configured to consist of multiple radially expandable petal-shaped components.

5. The electrocoagulation system according to claim 1, characterized in that, The distal end of the guidewire housing is provided with a diameter abrupt change section, the outer diameter of the distal end of the diameter abrupt change section being smaller than the outer diameter of its proximal end, which is used to form an abutment with the edge of the mesh when the guidewire housing passes through the mesh of the blood flow guiding stent, so as to limit the distal end of the guidewire housing from going too deep.

6. The electrocoagulation system according to claim 5, characterized in that, The diameter abrupt change section is provided with a development mark.

7. The electrocoagulation system according to claim 1, characterized in that, The length of the electrocoagulation guide wire is longer than the length of the guide wire shell.

8. The electrocoagulation system according to claim 7, characterized in that, The proximal end of the electrocoagulation guidewire is provided with a scale to indicate the extension length of the distal end of the electrocoagulation guidewire relative to the distal end of the guidewire housing.

9. The electrocoagulation system according to claim 1, characterized in that, The distal end of the electrocoagulation wire is made of a high-resistivity material.

10. The electrocoagulation system according to claim 1, characterized in that, It also includes a microcatheter for delivering the guidewire housing and the electrocoagulation guidewire located therein to the vicinity of the flow guiding stent.

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