Balloon, balloon catheter and ablation catheter

Abstract

The invention provides a balloon, a balloon catheter and an ablation catheter, and relates to the field of medical instruments. The expansion state of the balloon comprises a first extension section, a lens section and a second extension section; the lens section is arranged between the first extension section and the second extension section in the axial direction; the lens section comprises a converging structure made of an energy-permeable material; wherein the convergence structure is configured to converge energy from the lens section to a target convergence area. The balloon catheter comprises a balloon, an energy generator, a first axial fixing piece and a second axial fixing piece, the energy generator is arranged in the hollow channel of the lens section, and the energy generator has the length corresponding to the length of the lens section in the axial direction. The balloon catheter provided by the embodiment of the invention is applied to an ablation operation, accurate focusing of the target ablation area can be achieved based on the lens section, damage to surrounding tissues can be minimized while nerves in the target ablation area can be accurately targeted, and the effect of the ablation operation is improved.

Description

Technical Field

[0001] The present application relates to the field of medical devices, and in particular, to a balloon, a balloon catheter and an ablation catheter. Background Art

[0002] Ablation is a medical technique that destroys or removes body tissue through physical or chemical means. Common ablations include radiofrequency ablation (RFA) which uses high-frequency electric current to heat and destroy target tissue, laser ablation which uses laser energy to destroy diseased tissue, cryoablation which freezes and kills diseased tissue at extremely low temperatures (usually using liquid nitrogen or other coolants), and chemical ablation which uses the injection of chemicals to dissolve or destroy diseased tissue.

[0003] Energy is focused on the target tissue and specific nerve fibers or ganglia in the target tissue are destroyed to interrupt the excessive conduction of pathological nerve signals, thereby treating diseases caused by excessive sympathetic nerve activity, abnormal pain transmission or autonomic nervous system dysfunction (such as hypertension, arrhythmia, chronic pain, etc.). Common nerve ablation procedures include pulmonary artery denervation (PADN), renal artery denervation (RDN) and intravascular sympathetic nerve ablation (EDN). In addition, there are many other nerve ablation techniques that mainly target overactive or pathological nerve pathways and are used to treat refractory hypertension, arrhythmia, pain syndrome and other diseases.

[0004] When performing the above-mentioned nerve ablation surgery, interventional surgery is usually carried out with an ablation catheter. Common ablation catheters are equipped with ablation energy release elements on a catheter stent, and ablation of different target locations is achieved through the design of the arrangement of the ablation energy release elements.

[0005] However, the production process of ablation energy release elements is difficult and the development cycle is long, and the energy convergence effect needs to be improved. Summary of the Invention

[0006] The purpose of the embodiments of the present application is to provide a balloon, a balloon catheter and an ablation catheter, which can achieve accurate focusing on the target ablation area through the lens segment, and can minimize damage to surrounding tissues while accurately targeting the nerves in the target ablation area, thereby improving the effect of the ablation surgery.

[0007] In a first aspect, an embodiment of the present application provides a balloon, the expanded state of which includes: a first extended segment, a lens segment, and a second extended segment; the lens segment is arranged between the first extended segment and the second extended segment along the axial direction; the lens segment includes a convergence structure made of an energy-permeable material; wherein the convergence structure is configured to converge energy from the hollow channel of the lens segment to a target convergence area.

[0008] In the above-mentioned implementation process, the balloon provided by the embodiment of the present application includes a first extension segment, a lens segment, and a second extension segment, wherein the lens segment includes a convergence structure, which can converge the energy from the hollow channel of the lens segment to the target convergence area. By designing the convergence structure, it is possible to converge the energy at different depths, that is, to adjust the focus. The balloon structure provided by the embodiment of the present application is used in a catheter for interventional surgery, and is used in conjunction with an energy generator to achieve precise ablation of the target ablation point; not only can it achieve precise energy convergence, but it can also increase the temperature rise rate of the ablation point, shorten the duration of the ablation surgery, and enhance the patient's surgical experience.

[0009] Optionally, in an embodiment of the present application, the converging structure includes multiple first thickness segments and multiple second thickness segments; the radial dimensions of the first thickness segments and the second thickness segments are different; the multiple first thickness segments and the multiple second thickness segments are staggered in the axial direction.

[0010] In the above implementation process, the converging structure of the balloon provided in the embodiment of the present application includes a first thickness segment and a second thickness segment of different sizes in the radial direction. The first and second thickness segments are staggered in the axial direction to form a binary thickness distribution of the balloon. The balloon provided in the embodiment of the present application achieves control over the energy distribution from the hollow channel of the balloon by giving the lens segment the acoustic characteristics of a Bessel-type or Fresnel-type lens. Specifically, for the Bessel-type balloon, the first and second thickness segments are of the same length in the axial direction. By adjusting the number of the first and second thickness segments, the energy distribution from the hollow channel of the balloon can be controlled.

[0011] Optionally, in an embodiment of the present application, the lens segment includes an intermediate length segment; the intermediate length segment is arranged in the axial middle of the lens segment, and the converging structure is arranged on both sides of the intermediate length segment.

[0012] In the above-mentioned implementation process, the balloon provided by the embodiment of the present application includes a Fresnel-type balloon and a quasi-Bessel-type balloon, wherein the Fresnel-type balloon can be designed to have its length in the axial direction according to the Fresnel zone plate formula and the position where energy convergence needs to be controlled. The quasi-Bessel-type lens is a simplification of the Bessel lens structure, and precise control of the energy convergence position is achieved by flexibly controlling the length of the middle part. It can be seen that the balloon provided by the embodiment of the present application can be endowed with the acoustic structural characteristics of the Bessel lens, the Fresnel lens and the quasi-Bessel lens, and the flexible adjustment of its structural parameters can control the energy convergence in the target area, and is applied to the catheter setting in the ablation surgery, and cooperated with the use of the energy generator to facilitate the precise ablation of the target ablation position.

[0013] Optionally, in an embodiment of the present application, the balloon is a non-compliant balloon.

[0014] In this implementation, during ablation procedures, the non-compliant balloon ensures that ablation energy is evenly delivered to the target tissue through the tightly fitting balloon wall, preventing uneven energy distribution or tissue damage caused by overexpansion. Furthermore, its high burst pressure safely withstands the high-pressure environment required for surgery while stably supporting the integrated electrode or transducer, allowing precise positioning of the ablation target and thus enhancing the safety and effectiveness of ablation procedures.

[0015] In a second aspect, an embodiment of the present application provides a balloon catheter, which includes a balloon, an energy generator, a first axial fixing member and a second axial fixing member; wherein, the expanded state of the balloon includes: a first extension segment, a lens segment and a second extension segment; the lens segment is arranged between the first extension segment and the second extension segment along the axial direction; the energy generator is arranged in the hollow channel of the lens segment, and the energy generator has a length corresponding to the lens segment in the axial direction; the first axial fixing member is arranged in the hollow channel of the first extension segment and is fixedly connected to the first end of the energy generator; the second axial fixing member is arranged in the hollow channel of the second extension segment and is fixedly connected to the second end of the energy generator; wherein, the convergence structure of the lens segment is configured to converge the energy generated by the energy generator to a target convergence area.

[0016] In the above-mentioned implementation process, the balloon catheter provided by the embodiment of the present application, the energy generator is fixed in the hollow channel of the lens segment of the balloon; the balloon includes a first extension segment, a lens segment and a second extension segment, wherein the lens segment includes a convergence structure, which can converge the energy from the hollow channel of the lens segment to the target convergence area. By designing the convergence structure, it is possible to converge the energy at different depths, that is, to adjust the focus. The balloon catheter provided by the embodiment of the present application is used in the catheter of interventional surgery to achieve precise ablation of the target ablation point; it can not only achieve precise energy convergence, but also increase the temperature rise rate of the ablation point, shorten the duration of the ablation surgery, and improve the patient's surgical experience.

[0017] Optionally, in an embodiment of the present application, the converging structure includes a first thickness segment with a basic thickness d1 and a second thickness segment with a thickness d2; wherein the thickness d2 of the second thickness segment is a phase difference thickness d added to the basic thickness d1; the phase difference thickness d is determined based on the phase difference between adjacent wave groups generated by the energy generator.

[0018] In the above implementation process, the balloon catheter provided in the embodiment of the present application has a binary distributed thickness design, which can give the lens segment the acoustic characteristics of a Bessel-type or Fresnel-type lens. By adjusting the number of first and second thickness segments, the distribution of energy (such as energy emitted by an ultrasonic transducer) from the hollow channel of the balloon can be regulated. The use of the balloon catheter provided in the embodiment of the present application in denervation ablation surgery can accurately focus energy on the target ablation area, effectively reducing the duration of the ablation surgery and improving the patient's surgical comfort.

[0019] Optionally, in an embodiment of the present application, the lengths of the first thickness segment and the second thickness segment in the axial direction are approximately equal to or equal to the phase difference thickness d.

[0020] In the above implementation process, in the Bessel-type balloon catheter and quasi-Bessel-type balloon catheter provided in the embodiments of the present application, for each first thickness segment and second thickness segment, its length in the axial direction is set to be approximately equal to or equal to the phase difference thickness d, which can achieve precise notification of linear phase delay and generate a diffraction-free Bessel beam.

[0021] Optionally, in an embodiment of the present application, the convergence characteristics presented by the convergence structure are consistent with the convergence characteristics of the quasi-Bessel lens; and the middle length section of the lens segment is determined based on the position of the target convergence area.

[0022] In the above implementation process, the convergence characteristics of the convergence structure of the quasi-Bessel balloon catheter provided in the embodiment of the present application are consistent with the convergence characteristics of a quasi-Bessel lens. The embodiment of the present application provides an example of RDN surgery, in which the first and second thickness sections of the middle portion of the Bessel balloon catheter are adjusted. Simulations have verified that the quasi-Bessel balloon catheter provided in the embodiment of the present application can achieve energy convergence in the target ablation area required for RDN surgery. Furthermore, the structure is simple and highly manufacturable, providing strong and reliable support for ablation surgery.

[0023] Optionally, in an embodiment of the present application, the convergence characteristics presented by the convergence structure are consistent with the convergence characteristics of the Bessel lens; the number of the first thickness segment and the second thickness segment are n and n+1 respectively; wherein n is determined based on the position of the target convergence area.

[0024] In the above implementation, the Bessel-type balloon catheter provided in the embodiments of the present application has a convergence structure covering the entire lens segment of the balloon. Within the convergence structure, first and second thickness segments are staggered, and the first and second thickness segments have the same axial length. The number of first and second thickness segments can be designed to adjust the distribution of energy from the hollow channel of the balloon.

[0025] Optionally, in an embodiment of the present application, the converging structure includes n first thickness segments and n+1 second thickness segments; when the distance between the center point of the target converging area position and the outer surface of the lens segment in the radial direction is between [5.7 mm, 6.3 mm], n is 11.

[0026] In the above implementation process, the balloon catheter provided in the embodiments of the present application includes a Bessel-type balloon catheter, and the convergence characteristics exhibited by the convergence structure are consistent with the convergence characteristics of a Bessel lens. The embodiments of the present application provide an example of parameter design and adjustment using RDN surgery as an example. Simulations have verified that the Bessel-type balloon catheter provided in the embodiments of the present application can achieve energy convergence in the target ablation area required for RDN surgery.

[0027] Optionally, in an embodiment of the present application, the converging characteristics presented by the converging structure are consistent with the converging characteristics of the Fresnel lens; the lengths of the first thickness segment, the second thickness segment and the intermediate length segment in the axial direction are determined based on the position of the target converging area and according to the Fresnel zone plate formula.

[0028] In the above implementation process, the convergence characteristics of the Fresnel balloon catheter provided by the embodiment of the present application are consistent with the convergence characteristics of a Fresnel lens. The embodiment of the present application provides an example of calculating the lengths of the first and second thickness sections in the middle of a Fresnel balloon catheter using RDN surgery as an example. Simulations have verified that the Fresnel balloon catheter provided by the embodiment of the present application can achieve energy convergence in the target ablation area required for RDN surgery. Furthermore, the structure is simple and highly manufacturable, significantly shortening the duration of ablation surgery and providing strong and reliable support for ablation surgery.

[0029] Optionally, in an embodiment of the present application, the position of the target convergence area is determined according to the target physiological position to be ablated.

[0030] Optionally, in an embodiment of the present application, the target physiological location includes the sympathetic nerve location or parasympathetic nerve location of the renal artery, duodenum, celiac artery, abdominal aorta, common hepatic artery and proper hepatic artery.

[0031] In the above implementation process, the target convergence area of ​​the balloon catheter provided by the embodiment of the present application is determined based on the target physiological location to be ablated. The energy convergence location determined based on the physiological location achieves precise ablation, significantly improving the safety and effectiveness of the treatment. It can both destroy the target tissue and maximize the protection of surrounding healthy structures. The balloon catheter provided by the embodiment of the present application can significantly improve the surgical accuracy, efficiency, and safety of ablation procedures for complex diseases such as metabolic syndrome and intractable visceral pain, promoting the development of minimally invasive surgery towards high precision.

[0032] In a third aspect, an embodiment of the present application provides an ablation catheter, which includes an energy generator, a first axial fixing member, a second axial fixing member, and a balloon in an expanded state having a first extension segment, a lens segment, and a second extension segment; the lens segment is arranged between the first extension segment and the second extension segment, and the radial dimensions of the first extension segment and the second extension segment increase in the axial direction toward the lens segment and are connected to the lens segment; the energy generator is arranged in the hollow channel of the lens segment; the first axial fixing member is arranged in the hollow channel of the first extension segment and is fixedly connected to the first end of the energy generator; the second axial fixing member is arranged in the hollow channel of the second extension segment and is fixedly connected to the second end of the energy generator; the length of the energy generator in the axial direction is equal to that of the lens segment; wherein the convergence structure of the lens segment is configured to converge the energy generated by the energy generator into a target convergence area.

[0033] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the following embodiments are given in conjunction with the accompanying drawings for detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 Schematic diagram of the structure of a traditional balloon;

[0036] Figure 2 A schematic diagram of the structure of a Bessel-type balloon provided in an embodiment of the present application;

[0037] Figure 3 A schematic structural diagram of a Fresnel balloon provided in an embodiment of the present application;

[0038] Figure 4 A schematic structural diagram of a quasi-Bessel balloon provided in an embodiment of the present application;

[0039] Figure 5 Schematic diagram of the structure of a traditional balloon catheter;

[0040] Figure 6 This is a diagram showing the acoustic simulation results of a traditional balloon catheter provided in an embodiment of the present application;

[0041] Figure 7 A schematic structural diagram of a Bessel-type balloon catheter provided in an embodiment of the present application;

[0042] Figure 8A schematic structural diagram of a Fresnel balloon catheter provided in an embodiment of the present application;

[0043] Figure 9 A schematic structural diagram of a quasi-Bessel balloon catheter provided in an embodiment of the present application;

[0044] Figure 10 This is a diagram of acoustic simulation results of a Bessel-type balloon catheter provided in an embodiment of the present application;

[0045] Figure 11 This is a diagram of acoustic simulation results of a quasi-Bessel balloon catheter provided in an embodiment of the present application;

[0046] Figure 12 This is a diagram showing the acoustic simulation results of a Fresnel balloon catheter provided in an embodiment of the present application;

[0047] Figure 13 This is a diagram showing the biothermal simulation results of a traditional balloon catheter provided in an embodiment of the present application;

[0048] Figure 14 A diagram showing the biothermal simulation results of a Bessel-type balloon catheter provided in an embodiment of the present application;

[0049] Figure 15 A diagram showing the biothermal simulation results of a quasi-Bessel balloon catheter provided in an embodiment of the present application;

[0050] Figure 16 A diagram showing the biothermal simulation results of a Fresnel-type balloon catheter provided in an embodiment of the present application;

[0051] Figure 17 This is a temperature change curve at a 6mm radial position provided in an embodiment of the present application;

[0052] Figure 18 A schematic diagram of the temperature distribution at the axial center of the transducer 14 seconds after implementation of the present application;

[0053] Figure 19 A comparison diagram of the radial sound field distribution of the transducer provided in the embodiment of the present application;

[0054] Figure 20 This is a graph of the sound pressure increase at 6mm provided in an embodiment of the present application;

[0055] Icons: axial direction-Y; radial direction-R; balloon-100; first extension segment-110; lens segment-120; converging structure-121; first thickness segment-1211; second thickness segment-1212; intermediate length segment-122; second extension segment-130; balloon catheter-1000; energy generator-200; first axial fixing member-300; second axial fixing member-400. DETAILED DESCRIPTION

[0056] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of them. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0057] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the embodiments of the present application claimed for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present application without making creative efforts are within the scope of protection of the embodiments of the present application.

[0058] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0059] In the description of the embodiments of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, or are the orientation or position relationship in which the product of the embodiment of the application is usually placed when in use. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0060] Furthermore, terms such as "horizontal" and "vertical" do not necessarily mean that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0061] In the description of the embodiments of the present application, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in the embodiments of the present application based on the specific circumstances.

[0062] Ablation is a medical technique that destroys or removes body tissues through physical or chemical means. The physical means is to focus energy on the target tissue and destroy the specific nerve fibers or ganglia of the target tissue to interrupt the excessive conduction of pathological nerve signals, thereby treating diseases caused by excessive sympathetic nerve activity, abnormal pain transmission or autonomic dysfunction (such as hypertension, arrhythmia, chronic pain, etc.). Common nerve ablation surgeries include pulmonary artery denervation (PADN), renal artery denervation (RDN) and intravascular sympathetic nerve ablation (EDN). In addition, there are many other nerve ablation techniques, which mainly target overactive or pathological nerve pathways and are used to treat refractory hypertension, arrhythmia, pain syndrome and other diseases.

[0063] Currently, a common ablation catheter is one in which an ablation energy releasing element is arranged on a catheter stent, and ablation of different target locations is achieved by designing the arrangement of the ablation energy releasing element.

[0064] The inventors found that in this process, the production process of the ablation energy release element is difficult and the development cycle is long, and the energy concentration effect needs to be improved.

[0065] Based on this, the present application proposes a balloon, a balloon catheter, and an ablation catheter. The balloon comprises a first extension segment, a lens segment, and a second extension segment, wherein the lens segment comprises a convergence structure made of an energy-permeable material, the convergence structure being configured to converge energy from the hollow channel of the lens segment into a target convergence area. Furthermore, an energy generator is disposed within the hollow channel of the lens segment, forming the balloon catheter provided in an embodiment of the present application. This balloon catheter has a significant focusing effect, can quickly reach the ablation temperature, shortens the ablation procedure duration, and improves patient comfort.

[0066] The following uses pulmonary artery denervation (PADN), renal artery denervation (RDN) and intravascular sympathetic nerve ablation (EDN) as examples to briefly illustrate that the catheter provided in the embodiments of the present application can be used for nerve ablation surgery through the cavity of a biological body.

[0067] Renal artery denervation (RDN) is a minimally invasive treatment method that destroys the sympathetic nerves around the renal artery through radiofrequency ablation, ultrasound or microwave technology to reduce overactive sympathetic nerve activity, thereby effectively controlling refractory hypertension.

[0068] Endovascular Denervation (EDN) is a new minimally invasive procedure that improves blood sugar control in patients with type 2 diabetes by ablating peripheral sympathetic nerves such as the renal artery, duodenum, celiac artery, abdominal aorta, common hepatic artery, and proper hepatic artery.

[0069] Pulmonary hypertension (PH) refers to a clinical and pathophysiological syndrome characterized by structural or functional changes in the pulmonary vasculature due to a variety of heterogeneous diseases (etiologies) and different pathogenic mechanisms, leading to increased pulmonary vascular resistance and pulmonary artery pressure, which can subsequently progress to right heart failure and even death. The pathologies of PH that contribute to increased pulmonary artery pressure primarily include pulmonary hypertension, left heart disease, lung disease, pulmonary artery obstruction, unidentified factors, or multiple mechanisms. Pulmonary artery denervation (PADN) is a percutaneous pulmonary artery interventional therapy that uses a specific catheter to deliver radiofrequency energy to the sympathetic nerves in the pulmonary artery adventitia, causing demyelination and axonal fusion. This procedure inhibits sympathetic nerve activity, increases cardiac output, reduces pulmonary artery pressure, inhibits pathological pulmonary artery remodeling, and improves exercise tolerance and cardiac function.

[0070] In addition, the catheter provided in the embodiment of the present application can be used for ablation surgery through the cavity of a biological body, and can destroy specific nerve fibers or ganglia of the target tissue to interrupt the transitional conduction of pathological nerve signals, thereby treating diseases caused by excessive sympathetic nerve activity, abnormal pain transmission or autonomic dysfunction.

[0071] Please see Figures 1 to 4 , Figure 1 Schematic diagram of the structure of a traditional balloon; Figure 2 A schematic diagram of the structure of a Bessel-type balloon provided in an embodiment of the present application; Figure 3 A schematic structural diagram of a Fresnel balloon provided in an embodiment of the present application; Figure 4 This is a schematic diagram of the structure of the quasi-Bessel balloon provided in the embodiment of the present application. Figures 1 to 4 Both are in the expanded state of the balloon.

[0072] Balloon 100 is an inflatable and deflated hollow device made of a flexible material. It expands by injecting liquid or gas and has a wide range of medical applications. Common materials for balloon 100 include at least one of polyethylene (PE), polyethylene terephthalate (PET), nylon (PA), and polyether block amide (Pebax).

[0073] Please refer to Figure 1 , Figure 1 This is an example diagram of a traditional balloon. Figure 1 The balloon in the embodiment is a conical balloon, i.e., the radial dimensions of the two ends are larger than the radial dimensions of the middle. Common balloons include cylindrical and spherical balloons, where the middle portion of the balloon is generally the working section. However, the balloon provided in the embodiment of the present application has a lens-like design for the working section, giving the balloon the structural characteristics of a special lens to achieve energy control. It should be understood that the shape of the balloon (e.g., conical, spherical, cylindrical, etc.) should not limit the scope of protection of the balloon provided in the embodiment of the present application.

[0074] Please refer to Figures 2 to 4 The present application provides a balloon 100, and the expanded state of the balloon 100 includes: a first extension segment 110, a lens segment 120, and a second extension segment 130. It should be noted that the first extension segment 110 and the second extension segment 130 are the two ends of the balloon 100. In the application scenario of medical devices, the first extension segment 110 and the second extension segment 130 correspond to the distal end (the end of the medical device close to the operator) and the proximal end (the end of the medical device far from the operator). The lens segment 120 is a part with a lens configuration, which is generally arranged in the working section of the balloon 100. It should be noted that the lens segment 120 of the balloon 100 provided in the embodiment of the present application is a balloon 100 structure with a lens configuration, and the lens is not arranged on the balloon 100.

[0075] like Figures 2 to 4 As shown, the lens segment 120 is disposed along the axial direction (Y) between the first extension segment 110 and the second extension segment 130. One end of the first extension segment close to the lens segment 120 is connected to the lens segment 120, and the end of the second extension segment 130 close to the lens segment 120 is connected to the lens segment 120, forming the balloon 100.

[0076] The lens segment 120 includes a focusing structure 121 made of a material that is transparent to energy. The focusing structure 121 is configured to focus energy from the hollow channel of the lens segment 120 to a target focusing area.

[0077] In the above implementation process, the converging structure 121 of the lens segment 120 is made of a material that is energy-transmissive, and its material can be selected from common balloon 100 materials, such as polyethylene (PE), polyethylene terephthalate (PET), nylon (PA) and polyether block amide (Pebax).

[0078] pass Figures 1 to 4It can be seen that the balloon 100 provided in the embodiment of the present application includes a first extension segment 110, a lens segment 120 and a second extension segment 130, wherein the lens segment 120 includes a convergence structure 121, which can converge the energy from the hollow channel of the lens segment 120 to the target convergence area. By designing the convergence structure 121, it is possible to converge the energy at different depths, that is, to adjust the focus. The balloon 100 structure provided in the embodiment of the present application is used in a catheter for interventional surgery, and is used in conjunction with the energy generator 200 to achieve precise ablation of the target ablation point; not only can it achieve precise energy convergence, but it can also increase the temperature rise rate of the ablation point, shorten the duration of the ablation surgery, and improve the patient's surgical experience.

[0079] Please continue to see Figures 2 to 4 In an optional implementation manner of the embodiment of the present application, the converging structure 121 includes a plurality of first thickness segments 1211 and a plurality of second thickness segments 1212 .

[0080] The radial dimensions of the first thickness section 1211 and the second thickness section 1212 are different, such as Figures 2 to 4 As shown, a plurality of the first thickness segments 1211 and a plurality of the second thickness segments 1212 are staggered in the axial direction (Y).

[0081] In the above implementation process, the first thickness section 1211 and the second thickness section 1212 have different sizes in the radial direction (R), and the first thickness section 1211 and the second thickness section 1212 are staggered in the axial direction (Y), so that the balloon 100 provided in the embodiment of the present application has a binary thickness periodic functional distribution in the axial direction (Y). For example, the arrangement in the axial direction (Y) is the first thickness section 1211-second thickness section 1212-first thickness section 1211-second thickness section 1212...first thickness section 1211-second thickness section 1212-first thickness section 1211, or the second thickness section 1212-first thickness section 1211-second thickness section 1212...first thickness section 1211-second thickness section 1212.

[0082] Based on the above-mentioned binary distribution thickness design, the lens segment 120 can be given the acoustic characteristics of a Bessel-type or Fresnel-type lens, thereby being able to control the energy distribution from the hollow channel of the balloon 100.

[0083] A Fresnel lens is a thin, lightweight optical element that focuses or diverges light through a concentric ring structure. It discretizes the continuous curved surface of a traditional lens into stepped rings, leveraging the principles of diffraction and refraction to reduce thickness while maintaining optical performance. Its characteristics are lightweight, but there is some dispersion and efficiency loss.

[0084] The Fresnel binary distribution is a diffractive optical design that simulates the refractive effect of a traditional lens by discretizing concentric annular bands. Its core principle is to use the abrupt structure at the edges of the annular bands to generate optical path differences, approximating a quadratic phase profile. This enables focusing in a thin, planar structure, effectively concentrating energy beams without requiring complex geometric design.

[0085] A Bessel lens is a specialized optical element that produces non-diffracting Bessel beams. Known for their non-diffracting properties, Bessel beams can generate localized acoustic waves, forming standing wave patterns, also known as "frozen waves." By constructing a conical wavefront, the Bessel lens maintains a narrow beam diameter and long focal depth during propagation, overcoming the diffraction and diffusion issues of traditional Gaussian beams.

[0086] The Bessel binary distribution generates a nearly conical phase through a discretized ring-shaped structure to produce a non-diffracting Bessel beam. This design modulates the wavefront through annular diffraction, forming a beam with a long axial focal depth.

[0087] like Figure 2 As shown, Figure 2 The schematic diagram of the structure of the Bessel-type balloon provided in the embodiment of the present application is shown in FIG. Figure 2 The entire lens segment 120 of the balloon 100 is covered with a convergence structure 121. Within the convergence structure 121, first thickness segments 1211 and second thickness segments 1212 are staggered, and the first and second thickness segments 1211, 1212 have the same length in the axial direction (Y). The number of first and second thickness segments 1211, 1212 can be designed to adjust the distribution of energy from the hollow channel of the balloon 100.

[0088] Thus, it can be seen that the converging structure 121 of the balloon 100 provided in the embodiment of the present application includes a first thickness segment 1211 and a second thickness segment 1212 of different sizes in the radial direction (R). The first thickness segment 1211 and the second thickness segment 1212 are staggered in the axial direction (Y), forming a binary thickness distribution of the balloon 100. The balloon 100 provided in the embodiment of the present application achieves control of the energy distribution from the hollow channel of the balloon 100 by giving the lens segment 120 the acoustic characteristics of a Bessel-type or Fresnel-type lens. Specifically, for the Bessel-type balloon 100, the first thickness segment 1211 and the second thickness segment 1212 have the same length in the axial direction (Y). By adjusting the number of the first thickness segment 1211 and the second thickness segment 1212, the energy distribution from the hollow channel of the balloon 100 can be controlled.

[0089] Please continue to see Figure 3 and Figure 4 In an optional embodiment of the present application, the lens segment 120 also includes an intermediate length segment 122.

[0090] like Figure 3 and Figure 4 As shown, the middle length segment 122 is arranged at the axial middle portion of the lens segment 120 , and the converging structure 121 is arranged on both sides of the middle length segment 122 .

[0091] Figure 3 The structure diagram of the Fresnel type balloon 100 is shown. Figure 3 In the embodiment, the convergence structures 121 are evenly and symmetrically arranged on both sides of the middle length section 122, that is, the first thickness section 1211 and the second thickness section 1212 are staggered and symmetrically arranged on both sides of the middle length section 122. Figure 3 In the Fresnel balloon 100 shown, the lengths of the first thickness segment 1211 and the second thickness segment 1212 in the axial direction (Y) are determined according to the Fresnel zone plate formula based on the position of the target focusing area where energy convergence needs to be controlled.

[0092] Figure 4 The diagram shows the structure of the quasi-Bessel balloon 100. It should be noted that the quasi-Bessel lens is a specially designed optical element that can approximate the key characteristics of the Bessel beam (such as non-diffraction, self-repairing and long focal depth) while overcoming the complexity and energy loss problems of the traditional Bessel beam generation method by simplifying the structure. Figure 4 In the quasi-Bessel balloon 100 shown, Figure 2 Simplify the structure, Figure 2 The first thickness segment 1211 and the second thickness segment 1212 in the focusing structure of the middle lens segment 120 are removed, and the above-mentioned intermediate length segment 122 is generated after removal; the first thickness segment 1211 and the second thickness segment 1212 on both sides of the intermediate length segment 122 have the same length in the axial direction (Y). By designing the number and size of the first thickness segments 1211 and the second thickness segments 1212 retained on both sides, the energy distribution from the hollow channel of the balloon 100 can be controlled.

[0093] pass Figure 3 and Figure 4It can be seen that the balloon 100 provided in the embodiment of the present application includes a Fresnel-type balloon 100 and a quasi-Bessel-type balloon 100, wherein the Fresnel-type balloon 100 can be designed to have its length in the axial direction (Y) according to the Fresnel zone plate formula and the position where energy convergence needs to be controlled. The quasi-Bessel-type lens is a simplification of the Bessel lens structure, and precise control of the energy convergence position is achieved by flexibly controlling the length of the middle part. It can be seen that the balloon 100 provided in the embodiment of the present application can be endowed with the acoustic structural characteristics of a Bessel lens, a Fresnel lens, and a quasi-Bessel lens, and the flexible adjustment of its structural parameters can control the energy convergence in the target area, and is applied to the catheter setting in the ablation surgery, and cooperated with the use of the energy generator to contribute to the precise ablation of the target ablation position.

[0094] The balloon 100 provided in the embodiment of the present application is a non-compliant balloon (NC). Non-compliant balloons are generally made of high-strength, low-ductility materials (such as PET). Under high-pressure conditions, their diameter hardly changes with increasing pressure and they can accurately maintain a preset size.

[0095] During ablation procedures, the non-compliant balloon ensures that ablation energy is evenly delivered to the target tissue through the tightly fitting balloon wall, preventing uneven energy distribution or tissue damage caused by overexpansion. Furthermore, its high burst pressure safely withstands the high-pressure environment required for surgery while stably supporting the integrated electrode or transducer, allowing precise positioning of the ablation target and enhancing the safety and effectiveness of ablation procedures.

[0096] The present application also provides a balloon catheter 1000, which includes the aforementioned balloon 100. Before introducing the specific contents of the balloon catheter 1000 provided in the embodiment of the present application, it should be noted in advance that, in order to verify the reliability of the balloon catheter 1000, the present application embodiment conducted simulation experiments on the balloon catheter 1000, including acoustic simulation and biothermal simulation.

[0097] To conduct simulation experiments to verify the reliability of the balloon catheter 1000 provided in the embodiments of this application, a simulation model was first established. COMSOL Multiphysics (COMSOL Multiphysics, Burlington, MA, USA) was used for modeling. The modeling process is not described in detail here. However, to enable those skilled in the art to restore the structure of the balloon catheter 1000 provided in the embodiments of this application, the relevant parameters used in the modeling process (using a tubular ultrasonic transducer) are provided in Table 1.

[0098] Table 1

[0099] Parameter Type Numerical Inner diameter of ultrasonic transducer 1mm Ultrasonic transducer outer diameter 1.5mm Axial length of ultrasonic transducer 6mm Simulated artery inner diameter 4mm Simulated artery inner diameter 6mm Simulated tissue thickness 12mm Ultrasound absorption by water default value Ultrasound attenuation through arteries and tissues <![CDATA[50.5NP / m 2 ]]> Voltage 30V

[0100] It should be noted that all simulation experiments provided in the embodiments of the present application are performed under the same voltage / power excitation conditions.

[0101] The ultrasonic transducer used in the simulation experiments for the present embodiment operates at a frequency of 8.5 MHz. Because the transducer operates independently of the balloon 100, changes in the balloon 100 design do not affect the transducer's performance. Under the same excitation power, the acoustic field generated by different balloon 100 types remains consistent.

[0102] The balloon 100 used in the simulation had a diameter of 4 mm. Clinically, due to variations in blood vessel size, balloon 100 sizes ranging from 4 mm to 8 mm may be required. As the radius of balloon 100 changes, the distance between balloon 100 and the transducer also changes. However, simulation experiments have shown that the acoustic field distribution characteristics do not significantly change when the balloon 100 size ranges from 4 mm to 8 mm.

[0103] In addition, the waves emitted by the transducer resemble cylindrical wavefronts. Because the ultrasonic attenuation effect of the circulating water within the balloon 100 is minimal, a divergent effect that reduces the intensity may occur as the radius increases, but the effect on the shape of the sound field is negligible. It should be noted that the tubular piezoelectric ceramic transducer used in the embodiments of this application, in actual applications, uses of energy generators 200 in other shapes, such as prisms, are also within the scope of protection of the embodiments of this application.

[0104] It should be noted that, in the embodiment of the present application, when performing biothermal simulation (hereinafter referred to as Figures 13 to 16 ) , based on the effectiveness and safety thresholds for ultrasound ablation defined in IEC 60601-2-62 (Medical electrical equipment - Part 2-62: Particular requirements for the basic safety and essential performance of high-intensity therapeutic ultrasound (HITU) equipment). The effective ablation threshold is characterized by a thermal dose (T43) of 1800 seconds, while the safety threshold corresponds to a thermal dose (T43) of 60 seconds. Within the 54°C isotherm, the thermal dose at T43 exceeds 1800 seconds, meeting the effective ablation standard. Outside the 48°C isotherm, the thermal dose at T43 may be less than 60 seconds, remaining below the safety threshold to ensure the safety of adjacent tissues. This embodiment of the present application simulates the time required for several types of balloon catheters 1000 provided in the present application to reach 54°C at a 6mm ablation boundary to study the temperature rise, that is, the duration of the ablation procedure. It also simulates the distance between the 48°C isotherm and the vessel wall for several types of balloon catheters 1000 provided in the present application within a given ablation event to study the impact on non-target areas.

[0105] The following is the specific content of the balloon catheter 1000 provided in the embodiment of the present application.

[0106] The balloon catheter 1000 includes a balloon 100, an energy generator 200, a first axial fixing member 300, and a second axial fixing member 400. The balloon 100 includes the balloon 100 provided in the first aspect of the present application. The expanded state of the balloon 100 can be seen above and includes: a first extension segment 110, a lens segment 120, and a second extension segment 130; the lens segment 120 is disposed between the first extension segment 110 and the second extension segment 130 along the axial direction (Y).

[0107] Taking the structural diagram of a conventional balloon catheter as an example, the structure of the balloon catheter 1000 provided in the embodiment of the present application is introduced. Figure 5 , Figure 5 Schematic diagram of the structure of a conventional balloon catheter 0; Figure 5 As shown, the traditional balloon catheter 0 sets the energy generator 200 in the hollow channel in the middle of the balloon 100.

[0108] Energy generator 200, specifically the piezoelectric tubular transducer, utilizes radially polarized piezoelectric ceramics, demonstrating the efficient ability to transmit ultrasonic power outward from a central axis. This feature enables 360-degree energy convergence, enabling applications in intraluminal acoustic therapy (e.g., renal denervation ablation, RDN) to improve surgical efficiency and effectiveness.

[0109] Figure 5 In the figure, the transducer in the middle of the balloon catheter 1000 is a tubular piezoelectric ceramic transducer. Figure 5 Based on the reference Figure 6 and Figure 13 , Figure 6 This is a diagram showing the acoustic simulation results of a traditional balloon catheter provided in an embodiment of the present application; Figure 13 This is a diagram showing the biothermal simulation results of a traditional balloon catheter provided in an embodiment of the present application; Figure 6 In the figure, the horizontal axis is the radial dimension (unit, mm), the left vertical axis is the axial dimension (unit, mm), and the right vertical axis is the energy intensity (unit, Pa). Figure 6 It can be seen that the focusing effect of traditional balloon catheters is poor, and the energy is divergent. Figure 13 The biothermal simulation results shown are from Figure 13 It can be seen that the ablation time required by the traditional balloon catheter is 18 seconds, and the distance between the 48°C isotherm of the traditional balloon catheter and the blood vessel wall is 8.1 mm.

[0110] In the balloon catheter 1000 provided in an embodiment of the present application, the energy generator 200 is disposed in the hollow channel of the lens segment 120, and the energy generator 200 has a length in the axial direction (Y) corresponding to that of the lens segment 120. It should be noted that the corresponding length means that the length of the lens segment 120 can be determined based on the length of the energy generator 200. Optionally, the length of the lens segment 120 in the axial direction (Y) can be set to be consistent with the length of the energy generator 200; alternatively, the length of the lens segment 120 in the axial direction (Y) can be set to be slightly smaller than the length of the energy generator 200.

[0111] The first axial fixing member 300 is disposed in the hollow passage of the first extension section 110 and is fixedly connected to the first end of the energy generator 200; the second axial fixing member 400 is disposed in the hollow passage of the second extension section 130 and is fixedly connected to the second end of the energy generator 200. The fixing method of the energy generator 200 can be found in Figure 5 Similar to the fixing method of the energy generator of a traditional balloon catheter, both ends of the energy generator 200 are fixed by a first axial fixing member 300 and a second axial fixing member 400.

[0112] The converging structure 121 of the lens segment 120 is configured to converge the energy generated by the energy generator 200 into a target converging area.

[0113] Unlike traditional balloon catheters, the balloon catheter 1000 provided in the embodiment of the present application has an energy generator 200 fixed in the hollow channel of the lens segment 120 of the balloon 100; the balloon 100 includes a first extension segment 110, a lens segment 120, and a second extension segment 130, wherein the lens segment 120 includes a convergence structure 121, and the convergence structure 121 can converge the energy from the hollow channel of the lens segment 120 to the target convergence area. By designing the convergence structure 121, it is possible to converge the energy at different depths, that is, to adjust the focus. Using the balloon catheter 1000 provided in the embodiment of the present application in a catheter for interventional surgery can achieve precise ablation of the target ablation point; not only can it achieve precise energy convergence, but it can also increase the temperature rise rate of the ablation point, shorten the duration of the ablation surgery, and enhance the patient's surgical experience.

[0114] Please see Figures 7 to 9 , Figure 7 A schematic structural diagram of a Bessel-type balloon catheter provided in an embodiment of the present application; Figure 8 A schematic structural diagram of a Fresnel balloon catheter provided in an embodiment of the present application;

[0115] Figure 9Schematic diagram of the structure of the quasi-Bessel balloon catheter provided in an embodiment of the present application; the convergence structure 121 of the balloon 100 in the balloon catheter 1000 provided in an embodiment of the present application includes a first thickness segment 1211 with a base thickness d1 and a second thickness segment 1212 with a thickness d2.

[0116] The thickness d2 of the second thickness section 1212 is obtained by adding the phase difference thickness d to the basic thickness d1, that is, d2=d1+d; the phase difference thickness d is determined based on the phase difference between adjacent wave groups generated by the energy generator 200.

[0117] The Bessel lens reconstructs the incident light wavefront into a conical wavefront by precisely controlling the phase delay difference between adjacent annular wave groups, thereby generating a non-diffraction Bessel beam. Specifically, in the implementation of this application, the radial thickness of the balloon 100 is set to different sizes (first thickness section 1211, second thickness section 1212), and the light waves have a specific phase difference at different thickness positions, causing the wavefronts to form concentric annular interference during propagation, and ultimately superimposing the central bright spot (target convergence area) of the Bessel beam on the axis (perpendicular to the axial direction (Y)).

[0118] For example, taking an ultrasonic transducer as an example, the phase difference is defined as The phase difference thickness d can be calculated based on the following formula:

[0119]

[0120] Among them, c w is the speed of ultrasound propagation in tissue, c p is the speed of ultrasound propagation in the balloon 100, and f is the operating frequency. In addition, for traditional balloons, the base thickness d1 is generally 0.05 mm. Using a balloon 100 with a diameter of 4 mm, with a focal length of 6 mm (the location where nerves are most concentrated in denervation ablation, taking RDN surgery as an example, the target ablation area is within a radial range of 6 mm from the artery, which can effectively cover more than 95% of the renal artery nerves) as the target, c is taken. w =1500m / s,c p Substituting =2250m / s,f=8.5MHz into the above formula, the phase difference thickness d=0.265mm is calculated.

[0121] pass Figures 7 to 9As can be seen, the converging structure 121 of the balloon 100 in the balloon catheter 1000 provided in the embodiment of the present application is designed with a binary distributed thickness, which can give the lens segment 120 the acoustic characteristics of a Bessel-type or Fresnel-type lens. By adjusting the number of first thickness segments 1211 and second thickness segments 1212, the distribution of energy (such as energy emitted by an ultrasonic transducer) from the hollow channel of the balloon 100 can be regulated. The use of the balloon catheter 1000 provided in the embodiment of the present application in denervation ablation surgery can accurately focus energy on the target ablation area, effectively reducing the duration of the ablation surgery and improving the patient's surgical comfort.

[0122] Please see Figure 7 and Figure 9 , Figure 7 The Bessel-type balloon catheter 1000 and Figure 9 In the illustrated quasi-Bessel balloon catheter 1000 , the lengths of the first thickness section 1211 and the second thickness section 1212 in the axial direction (Y) are approximately equal to or equal to the phase difference thickness d.

[0123] For example, in the above implementation process, the calculated phase difference thickness d = 0.265 mm can be used to design the length of each first thickness segment 1211 and the second thickness segment 1212 in the axial direction (Y) in combination with the axial length of the ultrasonic transducer. For example, by calculating the length of each first thickness segment 1211 and the second thickness segment 1212 in the axial direction (Y), it is set to 0.26 mm.

[0124] In the Bessel-type balloon catheter 1000 and the quasi-Bessel-type balloon catheter 1000 provided in the embodiments of the present application, for each first thickness segment 1211 and the second thickness segment 1212, their lengths in the axial direction (Y) are set to be approximately equal to or equal to the phase difference thickness d, thereby achieving precise notification of the linear phase delay and generating a diffraction-free Bessel beam.

[0125] Please continue to see Figure 7 In the balloon catheter 1000 provided in the embodiment of the present application, the converging characteristics presented by the converging structure 121 of the Bessel-type balloon catheter 1000 are consistent with the converging characteristics of the Bessel lens.

[0126] The number of the first thickness segments 1211 and the number of the second thickness segments 1212 are n and n+1 respectively, wherein n is determined based on the position of the target convergence area. Figure 7As an example, the number of first thickness segments 1211 is n, and the number of second thickness segments 1212 is n+1; the arrangement in the axial direction (Y) is: second thickness segment 1212 - first thickness segment 1211 - second thickness segment 1212 ... first thickness segment 1211 - second thickness segment 1212. In some possible embodiments, the number of first thickness segments 1211 may be set to n+1, and the number of second thickness segments 1212 may be set to n; the arrangement in the axial direction (Y) is: first thickness segment 1211 - second thickness segment 1212 - first thickness segment 1211 - second thickness segment 1212 ... first thickness segment 1211 - second thickness segment 1212 - first thickness segment 1211.

[0127] As can be seen, in the Bessel-type balloon catheter 1000 provided in the embodiment of the present application, the entire lens segment 120 of the balloon 100 is covered with a convergence structure 121. Within the convergence structure 121, first thickness segments 1211 and second thickness segments 1212 are staggered, and the first thickness segments 1211 and second thickness segments 1212 have the same length in the axial direction (Y). The distribution of energy from the hollow channel of the balloon 100 can be adjusted by designing the number of first thickness segments 1211 and second thickness segments 1212.

[0128] Please Figure 7 See the basis of Figure 10 and Figure 14 , Figure 10 This is a diagram of acoustic simulation results of a Bessel-type balloon catheter provided in an embodiment of the present application; Figure 14 A diagram showing the biothermal simulation results of a Bessel-type balloon catheter provided in an embodiment of the present application; in an optional implementation of an embodiment of the present application, the converging structure 121 includes n first thickness segments 1211 and n+1 second thickness segments 1212 .

[0129] When the distance between the center point of the target convergence area and the outer surface of the lens segment 120 in the radial direction (R) is between [5.7 mm, 6.3 mm], n is 11. Preferably, the distance between the center point of the target convergence area and the base thickness of the outer surface of the lens segment 120 in the radial direction (R) is optimally controlled to be 6 mm.

[0130] by Figure 7 Taking the structure shown as an example, according to the requirements of RDN, the target ablation area is within a radial range of 6 mm from the artery, effectively covering more than 95% of the renal artery nerves. For the Bessel-type balloon 100, the embodiment of the present application uses a first thickness segment 1211 and a second thickness segment 1212 of 0.26 mm (approximate phase difference thickness d, the above phase difference thickness d calculated result is 0.265), which visually presents an "annular gap" structure. Figure 7In the figure, there are 12 second thickness segments 1212 and 11 first thickness segments 1211 on the balloon 100, which can achieve the desired focal length of 6 mm.

[0131] To verify Figure 7 The reliability of the structure, the embodiment of the present application was subjected to acoustic simulation, and the acoustic simulation results of the Bessel type balloon catheter 1000 are as follows Figure 10 shown. Figure 10 In the figure, the horizontal axis is the radial dimension (unit, mm), the left vertical axis is the axial dimension (unit, mm), and the right vertical axis is the energy intensity (unit, Pa). Figure 10 It can be seen that the Bessel lens balloon 100 exhibits a convergence pattern of a triangular area at a depth of 6 mm, which can achieve energy convergence in the target ablation area required for RDN surgery.

[0132] and biothermal simulation, from Figure 14 The biothermal simulation results shown show that Figure 14 It can be seen that the ablation time required by the Bessel-type balloon catheter 1000 is 25 seconds, and the distance between the 48°C isotherm of the Bessel-type balloon catheter 1000 and the blood vessel wall is 7.1 mm. The impact on non-target areas is very small, and a safe ablation procedure can be achieved.

[0133] pass Figure 7 、 Figure 10 and Figure 14 As can be seen, the balloon catheter 1000 provided in the embodiments of the present application includes a Bessel-type balloon catheter 1000, and the focusing characteristics exhibited by the focusing structure 121 are consistent with the focusing characteristics of a Bessel lens. The embodiments of the present application provide an example of parameter design and adjustment using RDN surgery as an example. Simulations have verified that the Bessel-type balloon catheter 1000 provided in the embodiments of the present application can achieve energy focusing in the target ablation area required for RDN surgery.

[0134] Please Figure 9 See the basis of Figure 11 and Figure 15 , Figure 11 This is a diagram of acoustic simulation results of a quasi-Bessel balloon catheter provided in an embodiment of the present application; Figure 15 This is a diagram of the biothermal simulation results of the quasi-Bessel balloon catheter provided in an embodiment of the present application; in the balloon catheter 1000 provided in an embodiment of the present application, the convergence characteristics presented by the convergence structure 121 of the quasi-Bessel balloon catheter 1000 are consistent with the convergence characteristics of the quasi-Bessel lens.

[0135] Figure 9Shown is a schematic structural diagram of a quasi-Bessel balloon catheter 1000. It should be noted that the quasi-Bessel lens can approximate the key characteristics of the Bessel beam, while overcoming the complexity and energy loss problems of the traditional Bessel beam generation method by simplifying the structure. Figure 9 In the quasi-Bessel balloon 100 shown, Figure 7 The simplified structure of the Bessel-type balloon 100 is shown. Figure 7 The first thickness segment 1211 and the second thickness segment 1212 in the focusing structure of the middle lens segment 120 are removed, and the above-mentioned intermediate length segment 122 is generated after removal; the first thickness segment 1211 and the second thickness segment 1212 on both sides of the intermediate length segment 122 have the same length in the axial direction (Y). By designing the number and size of the first thickness segments 1211 and the second thickness segments 1212 retained on both sides, it is possible to achieve regulation of the energy distribution emitted by the energy generator 200 in the hollow channel of the balloon 100.

[0136] In the above implementation process, the middle length section 122 of the lens section 120 is determined based on the position of the target convergence area.

[0137] Still taking RDN surgery as an example, the target ablation area is within a radial range of 6 mm from the artery, effectively covering more than 95% of the renal artery nerves. Figure 9 Taking the quasi-Bessel-type balloon 100 shown as an example, three rings on each side (the second thickness section 1212) are retained, and the six rings in the center (the second thickness section 1212) are removed. The transducer is thereby effectively divided into three parts: upper, middle, and lower. The middle part corresponds to the peripheral tissue area and is the main ablation target area. The ultrasonic waves emitted by this part of the transducer directly penetrate and interact with the target area. At the same time, the transducer parts located at the upper and lower parts adopt a Bessel acoustic structure, which helps to refract part of the energy to the middle target area. Therefore, the energy received by the middle target area is greater than the original energy.

[0138] To verify Figure 9 The reliability of the balloon catheter 1000 is shown, and the embodiment of the present application provides Figure 9 Schematic diagram of acoustic simulation results of the structure in FIG. The acoustic simulation results of the quasi-Bessel balloon catheter 1000 are shown in FIG. Figure 11 shown. Figure 11 In the figure, the horizontal axis is the radial dimension (unit, mm), the left vertical axis is the axial dimension (unit, mm), and the right vertical axis is the energy intensity (unit, Pa). Figure 11 It can be seen that the quasi-Bessel lens balloon 100 has a significant focusing effect at a depth of 6 mm, and can achieve energy focusing on the target ablation area required for RDN surgery.

[0139] and biothermal simulation, from Figure 16The biothermal simulation results shown show that Figure 16 As can be seen, the ablation time required by the quasi-Bessel balloon catheter 1000 is 14 seconds, which is approximately 22% shorter than that of a conventional balloon catheter. The 48°C isotherm of the quasi-Bessel balloon catheter 1000 is 7.8 mm away from the vessel wall, minimizing the impact on non-target areas and enabling safe ablation procedures.

[0140] pass Figure 9 、 Figure 11 and Figure 16 As can be seen, the convergence characteristics exhibited by the convergence structure 121 of the quasi-Bessel balloon catheter 1000 provided in the embodiment of the present application are consistent with the convergence characteristics of a quasi-Bessel lens. Taking RDN surgery as an example, the embodiment of the present application adjusts the first thickness section 1211 and the second thickness section 1212 in the middle portion of the Bessel balloon catheter 1000. Simulations have verified that the quasi-Bessel balloon catheter 1000 provided in the embodiment of the present application can achieve energy convergence in the target ablation area required for RDN surgery. Furthermore, the structure is simple and highly manufacturable, providing strong and reliable support for ablation surgery.

[0141] Please Figure 8 See the basis of Figure 12 and Figure 15 , Figure 12 This is a diagram showing the acoustic simulation results of a Fresnel balloon catheter provided in an embodiment of the present application; Figure 15 This is a diagram of the biothermal simulation results of the Fresnel-type balloon catheter provided in an embodiment of the present application. In the balloon catheter 1000 provided in an embodiment of the present application, the converging characteristics presented by the converging structure 121 of the Fresnel-type balloon catheter 1000 are consistent with the converging characteristics of the Fresnel lens.

[0142] In the embodiment of the present application, the lengths of the first thickness segment 1211 , the second thickness segment 1212 and the intermediate length segment 122 in the axial direction (Y) are determined based on the position of the target convergence area and according to the Fresnel zone plate formula.

[0143] In the embodiment of the present application, for the Fresnel balloon catheter 1000, its length in the axial direction (Y) is determined based on the following formula:

[0144]

[0145] Among them, F L is the focal depth of 6 mm, and λ is the wavelength of ultrasound in tissue. Based on the transducer length (Table 1), the maximum value of N is 7. Therefore, the path length from the "focus" to the boundary of any ring (second thickness segment 1212) is greater than F L An integer multiple of half the wavelength λ.

[0146] To verify Figure 8 The reliability of the balloon catheter 1000 is shown, and the embodiment of the present application provides Figure 8 Schematic diagram of acoustic simulation results of the structure in FIG. Acoustic simulation results of Fresnel balloon catheter 1000 are shown in FIG. Figure 12 shown. Figure 12 In the figure, the horizontal axis is the radial dimension (unit, mm), the left vertical axis is the axial dimension (unit, mm), and the right vertical axis is the energy intensity (unit, Pa). Figure 12 It can be seen that the Fresnel balloon 100 has a significant focusing effect at a depth of 6 mm, and can achieve energy focusing in the target ablation area required for RDN surgery.

[0147] and biothermal simulation, from Figure 15 The biothermal simulation results shown show that Figure 15 As can be seen, the ablation time required by the quasi-Bessel balloon catheter 1000 is 14 seconds, which is approximately 22% shorter than that of a conventional balloon catheter. The 48°C isotherm of the Fresnel balloon catheter 1000 is 7.3 mm away from the vessel wall, minimizing the impact on non-target areas and enabling safe ablation procedures.

[0148] pass Figure 8 、 Figure 12 and Figure 15 It can be seen that the convergence characteristics exhibited by the convergence structure 121 of the Fresnel balloon catheter 1000 provided in the embodiment of the present application are consistent with the convergence characteristics of a Fresnel lens. Taking RDN surgery as an example, the embodiment of the present application calculated the lengths of the first thickness section 1211 and the second thickness section 1212 in the middle portion of the Fresnel balloon catheter 1000. Simulations have verified that the Fresnel balloon catheter 1000 provided in the embodiment of the present application can achieve energy convergence in the target ablation area required for RDN surgery. Furthermore, the structure is simple and highly manufacturable, significantly shortening the duration of ablation surgery and providing strong and reliable support for ablation surgery.

[0149] Please Figures 5 to 8 See the basis of Figure 17 , Figure 17 This is a temperature change curve at a 6mm radial position provided in an embodiment of the present application; Figure 17 In the figure, the horizontal axis is time (unit, s), the vertical axis is the temperature change at the 6mm radial position (unit, ℃), the black square mark point line is the temperature change curve of the traditional balloon catheter 0, the red circle mark point line is the temperature change curve of the Bessel type balloon catheter 1000, the blue equilateral triangle mark point line is the temperature change curve of the Fresnel type balloon catheter 1000, and the pink and purple inverted triangle mark point line is the temperature change curve of the quasi-Bessel type balloon catheter 1000. Figure 17As can be seen, the slopes of the Fresnel and quasi-Bessel balloon catheters 1000 are the same and highest, indicating the fastest temperature rise. The temperatures of these two balloons 1000 are 2-4°C higher than those of conventional balloon catheters, significantly reducing ablation procedure time.

[0150] Please Figures 5 to 8 See the basis of Figure 18 , Figure 18 This is a schematic diagram of the temperature distribution at the axial center of the transducer provided in the embodiment of the present application after 14 seconds; Figure 18 In the figure, the horizontal axis is the radial distance (unit, mm), the vertical axis is the temperature (unit, ℃), the black square mark point line is the temperature curve of the traditional balloon catheter 0, the red circle mark point line is the temperature curve of the Bessel type balloon catheter 1000, the blue equilateral triangle mark point line is the temperature curve of the Fresnel type balloon catheter 1000, and the pink and purple inverted triangle mark point line is the temperature curve of the quasi-Bessel type balloon catheter 1000. Figure 18 As can be seen, within the 1.5 mm range, the temperatures of the four balloons 100 are similar. Within the 1.5-2.5 mm range, the Fresnel and Quasi-Bessel balloon catheters 1000 have the highest and similar temperatures, with the Bessel balloon catheter 1000 slightly lower but still higher than the conventional balloon. Within the 2.5-6 mm range, the temperatures of the Fresnel and Quasi-Bessel balloon catheters 1000 are similar, approximately 3°C higher than the conventional balloon, while the Bessel balloon catheter 1000 is slightly lower than the conventional balloon. Beyond 6 mm, the temperatures of the Fresnel, Quasi-Bessel, and conventional balloon catheters are similar.

[0151] Please refer to Figure 19 and Figure 20 , Figure 19 A comparison diagram of the radial sound field distribution of the transducer provided in the embodiment of the present application; Figure 20 This is a graph of the sound pressure increase at 6mm provided in the embodiment of the present application; Figure 19 In the figure, the horizontal axis is the radial distance (unit, mm), the vertical axis is the absolute sound pressure (unit, MPa), the black line is the absolute sound pressure curve of the traditional balloon catheter 0, the red line is the absolute sound pressure curve of the Bessel-type balloon catheter 1000, the blue line is the absolute sound pressure curve of the Fresnel-type balloon catheter 1000, and the pink-purple line is the absolute sound pressure curve of the quasi-Bessel-type balloon catheter 1000. Figure 20 In the figure, the vertical axis is the sound pressure intensity at 6 mm (unit, AU), the red column is the sound pressure intensity of the traditional balloon catheter 0, the green column is the sound pressure intensity of the Bessel-type balloon catheter 1000, the dark blue column is the sound pressure intensity of the Fresnel-type balloon catheter 1000, and the light blue column is the sound pressure intensity of the quasi-Bessel-type balloon catheter 1000.

[0152] It can be clearly seen from the figure that compared with the traditional balloon, the balloon 100 equipped with a lens has a waveform peak at about 6 mm. Figure 20 As shown in the figure, the normalized sound pressure intensity at 6 mm is compared with that of a conventional balloon. It is observed that the Fresnel lens balloon 100 has the largest increase in sound intensity, approximately twice that of the conventional balloon. This is followed by the quasi-Bessel lens balloon 100, with an increase of 100%. The Bessel lens balloon 100 has an increase of approximately 50%. Compared to the conventional balloon, all three lens-type balloons 100 exhibit a significant peak in sound intensity at 6 mm.

[0153] The simulation results above demonstrate that the Fresnel and quasi-Bessel balloon catheters 1000 and 1000 provided in the present invention have significantly superior heating performance compared to conventional balloon catheters, reaching effective ablation temperatures in a shorter time. Clinically, this translates to a shorter pain tolerance and improved overall treatment comfort for patients.

[0154] In an optional implementation manner of the embodiment of the present application, the position of the target convergence area is determined according to the target physiological position to be ablated.

[0155] For example, in the treatment of refractory hypertension, renal artery denervation (RDN) requires precise targeting of sympathetic nerve fibers in the renal artery adventitia. An ablation catheter (such as radiofrequency or the ultrasonic balloon catheter 1000 provided in the present application) focuses energy on a specific circumferential region of the vessel wall, forming a circular ablation zone that disrupts overactive nerve signaling while avoiding damage to the vascular lining or adjacent renal parenchyma.

[0156] Optionally, the target physiological positions in the embodiments of the present application include the sympathetic nerve positions or parasympathetic nerve positions of the renal artery, duodenum, celiac artery, abdominal aorta, common hepatic artery and proper hepatic artery.

[0157] The target convergence area of ​​the balloon catheter 1000 provided in the embodiment of the present application is determined based on the physiological location of the target to be ablated. This determines the convergence location of energy based on the physiological location, achieving precise ablation and significantly improving the safety and effectiveness of the treatment. This method can both destroy the target tissue and maximize the protection of surrounding healthy structures. The balloon catheter 1000 provided in the embodiment of the present application can significantly improve the surgical accuracy, efficiency, and safety of ablation procedures for complex diseases such as metabolic syndrome and intractable visceral pain, driving minimally invasive surgery towards high precision.

[0158] An embodiment of the present application further provides an ablation catheter, which includes an energy generator, a first axial fixing member, a second axial fixing member, and a balloon having a first extension segment, a lens segment, and a second extension segment in an expanded state.

[0159] The lens segment is arranged between the first extension segment and the second extension segment, and the radial dimensions of the first extension segment and the second extension segment increase in the axial direction toward the lens segment and are connected to the lens segment. Figures 7 to 9 As shown in the balloon structure, the first extension segment and the second extension segment are conical, and the radial size gradually increases toward the lens segment.

[0160] The energy generator is arranged in the hollow channel of the lens segment; the first axial fixing member is arranged in the hollow channel of the first extension segment and is fixedly connected to the first end of the energy generator; the second axial fixing member is arranged in the hollow channel of the second extension segment and is fixedly connected to the second end of the energy generator.

[0161] like Figures 7 to 9 As shown, the lengths of the energy generator and the lens segment in the axial direction are equal. The converging structure of the lens segment is configured to converge the energy generated by the energy generator into a target convergence area.

[0162] The present invention successfully developed Bessel- and Fresnel-type lens configurations by implementing a periodic functional distribution of axial binary thickness within the balloon. The balloon provided by the present invention, endowed with the optical structural characteristics of both Bessel and Fresnel lenses, can effectively focus acoustic energy at an appropriate focal depth. When the balloon provided by the present invention is applied in ablation procedures, the acoustic pressure at the ablation radius is significantly increased, and the temperature rise time is effectively shortened, thereby significantly reducing the duration of the ablation procedure and significantly improving the surgical outcome.

[0163] In this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the elements.

[0164] The above description is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and variations of the present application are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A balloon, characterized in that: The expanded state of the balloon includes: a first extended segment, a lens segment, and a second extended segment; The lens segment is arranged between the first extension segment and the second extension segment along the axial direction; The lens segment includes a focusing structure made of an energy-transmissive material; Wherein, the converging structure is configured to converge the energy from the hollow channel of the lens segment into a target converging area.

2. The balloon according to claim 1, wherein The converging structure includes a plurality of first thickness segments and a plurality of second thickness segments; The radial dimensions of the first thickness section and the second thickness section are different; A plurality of the first thickness sections and a plurality of the second thickness sections are staggered in the axial direction.

3. The balloon according to claim 1, wherein The lens segment includes an intermediate length segment; The middle length section is arranged at the axial middle portion of the lens section, and the converging structures are arranged on both sides of the middle length section.

4. The balloon according to claim 1, wherein The balloon is a non-compliant balloon.

5. A balloon catheter, characterized in that: The balloon catheter comprises a balloon, an energy generator, a first axial fixing member and a second axial fixing member; wherein the balloon in an expanded state comprises: a first extended segment, a lens segment and a second extended segment; the lens segment is arranged between the first extended segment and the second extended segment along the axial direction; The energy generator is arranged in the hollow channel of the lens segment, and the energy generator has a length corresponding to that of the lens segment in the axial direction; The first axial fixing member is disposed in the hollow channel of the first extension section and is fixedly connected to the first end of the energy generator; the second axial fixing member is disposed in the hollow channel of the second extension section and is fixedly connected to the second end of the energy generator; The converging structure of the lens segment is configured to converge the energy generated by the energy generator into a target convergence area. The balloon catheter according to claim 5 , wherein: The converging structure includes a first thickness segment having a base thickness d1 and a second thickness segment having a thickness d2; The thickness d2 of the second thickness segment is obtained by adding a phase difference thickness d to the basic thickness d1; the phase difference thickness d is determined based on the phase difference between adjacent wave groups generated by the energy generator.

7. The balloon catheter according to claim 6, characterized in that in, The lengths of the first thickness section and the second thickness section in the axial direction are approximately equal to or equal to the phase difference thickness d.

8. The balloon catheter according to claim 7, characterized in that in, The converging characteristics presented by the converging structure are consistent with the converging characteristics of the quasi-Bessel lens; The middle length of the lens segment is determined based on the position of the target convergence area.

9. The balloon catheter according to claim 7, characterized in that: in, The converging characteristics presented by the converging structure are consistent with the converging characteristics of the Bessel lens; The number of the first thickness segments and the number of the second thickness segments are n and n+1 respectively; wherein n is determined based on the position of the target convergence area.

10. The balloon catheter according to claim 9, characterized in that The converging structure includes n first thickness segments and n+1 second thickness segments; When the distance between the center point of the target converging area and the outer surface of the lens segment in the radial direction is between [5.7 mm, 6.3 mm], n is 11.

11. The balloon catheter according to claim 6, characterized in that in, The converging characteristics presented by the converging structure are consistent with the converging characteristics of the Fresnel lens; The lengths of the first thickness segment, the second thickness segment, and the intermediate length segment in the axial direction are determined based on the position of the target converging area and according to a Fresnel zone plate formula.

12. The balloon catheter according to any one of claims 8 to 11, characterized in that: in, The position of the target convergence area is determined according to the target physiological position to be ablated.

13. The balloon catheter according to claim 12, characterized in that The target physiological locations include sympathetic nerve locations or parasympathetic nerve locations of the renal artery, duodenum, celiac artery, abdominal aorta, common hepatic artery and proper hepatic artery.

14. An ablation catheter, characterized in that: The ablation catheter includes an energy generator, a first axial fixing member, a second axial fixing member, and a balloon having a first extension segment, a lens segment, and a second extension segment in an expanded state; The lens segment is arranged between the first extension segment and the second extension segment, and the radial dimensions of the first extension segment and the second extension segment increase in the axial direction toward the lens segment, and the lens segment is connected to the lens segment; The energy generator is disposed in the hollow channel of the lens segment; the first axial fixing member is disposed in the hollow channel of the first extension segment and is fixedly connected to the first end of the energy generator; the second axial fixing member is disposed in the hollow channel of the second extension segment and is fixedly connected to the second end of the energy generator; The lengths of the quantity generator and the lens segment in the axial direction are equal; The converging structure of the lens segment is configured to converge the energy generated by the energy generator into a target convergence area.

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