An airway stent

Abstract

This invention discloses an airway support, which is a monofilament structure wound into a spiral shape. The diameter of the airway support is 0.12-0.45 mm, and the ratio of the radial force to the wire diameter is 0.02-0.30 N / mm. 2 When this airway stent is installed in the trachea, part of the stent will be embedded in the inner wall of the trachea, while the rest will protrude out of the inner wall of the trachea. Because the wire diameter of the airway stent is small, the protruding part of the airway stent will be shorter than the cilia on the inner wall of the trachea, so as not to hinder the movement of the cilia to clear sputum. Moreover, by setting the airway stent to have sufficient radial force, it also avoids the situation where the trachea cannot be opened due to the small wire diameter of the airway stent.

Description

Technical Field

[0001] This invention relates to the technical field of airway stents, and particularly to an airway stent. Background Technology

[0002] COPD is a progressive lung function impairment disease with no cure. It causes permanent enlargement of alveoli and bronchioles, damage to elastic fibers, gas retention, and lung overinflation, which seriously affects patients' quality of life and life expectancy.

[0003] Current treatments for severe emphysema include: lung volume reduction surgery (LVRS), which is effective but highly invasive and risky; physical compression of diseased tissue with coils or clips, but may affect healthy lung tissue and cause complications; one-way valve technology, which requires no bypass ventilation and is applicable to less than 20% of patients; and bronchoscopic vapor ablation (BTVA) and injection of colloids or sealants, which can reduce lung volume but carry risks of local toxicity and complications.

[0004] Overall, existing technologies each have their limitations, and there is a lack of safe and widely applicable minimally invasive treatment options.

[0005] In the study of emphysema, airway stents are a key research area. Specifically, the tracheal mucosa is covered with a layer of mucus secreted by goblet cells and mucous glands. This mucus blanket is approximately 5-10 micrometers thick and consists of two layers: a thin sol layer where cilia move freely, and a viscous gel layer that traps invading pathogens. Each respiratory epithelial cell has approximately 200-300 cilia extending from its tip, each about 6-7 micrometers long and only 0.2 micrometers in diameter. These cilia rhythmically move at a frequency of 1000-1500 times per minute, always in a uniform direction—towards the pharynx. This movement is not random but follows a sophisticated "force-recovery stroke" pattern: forward extension is rapid and powerful, propelling the upper mucus layer like a paddle; backward retraction is slow and gentle, reducing adverse resistance. This asymmetrical oscillation allows the mucus blanket to move continuously toward the throat at a speed of about 5-20 millimeters per minute, and the entire mucus clearance cycle of the tracheobronchial tree takes about 24 hours.

[0006] This layer of mucus acts like a constantly moving "flypaper," trapping inhaled dust particles, PM2.5, pollen, bacteria, viruses, and shed epithelial cells. When this mucus containing foreign objects is pushed into the throat, it triggers a cough reflex—the glottis closes, chest pressure increases sharply, the glottis suddenly opens, and a high-speed airflow expels the phlegm from the airways. A complete cough can generate airflow speeds exceeding 160 km / h, sufficient to clear secretions from deep within the airways. A normal person clears approximately 10-100 ml of airway secretions daily in this way, most of which is unconsciously swallowed and neutralized by stomach acid.

[0007] However, this delicate airway cleaning system is forcibly disrupted after a tracheal stent is implanted. Whether it's a bare metal stent or a covered stent, it forms a physical barrier within the airway. The metal mesh or covered surface of the stent adheres tightly to the airway mucosa, directly flattening and burying the ciliated epithelium of the stent segment. The cilia lose their physical space to move, and the mucus blanket breaks on the stent surface, unable to continue moving upstream. Even more problematic is that the stent itself, as a foreign body, stimulates the airway mucosa to produce more secretions—a protective response that actually exacerbates the sputum buildup. Sputum distal to the stent, due to obstructed propulsion, can only accumulate, concentrate, and become viscous at the lower edge of the stent, forming sputum plugs or crusts, further worsening airway obstruction. Patients experience recurring, irritating dry coughs and difficulty expectorating, sometimes requiring postural drainage or suctioning to assist in expectoration. In severe cases, sputum crusts completely block the stent lumen, leading to stent failure and even endangering life. This is also an important reason why routine airway humidification, expectorant medication, and regular bronchoscopic cleaning are necessary after airway stent placement in clinical practice.

[0008] The disruption of the mucociliary clearance system by such stents has prompted the medical community to continuously explore more ideal solutions, such as developing thinner stent materials to reduce epithelial compression, designing drug-coated stents to inhibit excessive secretion, or developing biodegradable stents to achieve airway function reconstruction. Summary of the Invention

[0009] The purpose of this invention is to provide an airway stent to solve the problem of existing tracheal stents obstructing sputum expectoration.

[0010] To address the aforementioned technical problems, this invention provides an airway support, wherein the airway support is a monofilament structure wound into a spiral shape, the diameter of the filament is 0.12-0.45 mm, and the ratio of the radial force to the filament diameter is 0.02-0.30 N / mm. 2 .

[0011] In one embodiment, the airway support is made of a metal material; or the airway support is made of a combination of a metal material and a biodegradable material.

[0012] In one embodiment, the airway support has a wire diameter of 0.12-0.25 mm; the airway support is made of metal.

[0013] In one embodiment, the airway stent has a wire diameter of 0.15-0.3 mm; the airway stent is made of a combination of metal and biodegradable materials.

[0014] In one embodiment, the diameter of the airway support is 3-15 mm.

[0015] In one embodiment, the airway support includes multiple corrugated coils connected to each other in a spiral shape, and the axial dimension of the corrugated coils is 7-20 mm.

[0016] In one embodiment, the diameter of the airway support is 3-15 mm; the airway support includes multiple corrugated coils, which are interconnected in a spiral shape, and the axial dimension of the corrugated coils is 7-20 mm.

[0017] In one embodiment, the airway support includes a plurality of wave coils connected to each other in a spiral shape, with sputum clearance channels separated between adjacent wave coils, and the sputum clearance channels are arranged in a spiral shape on the airway support.

[0018] In one embodiment, the ratio of the width of the spiral sputum drainage channel to the width of the wave loop is 0.6-0.9.

[0019] In one embodiment, the airway support includes multiple peaks and multiple troughs, which are arranged alternately along a spiral trajectory; a plane perpendicular to the axial direction of the airway support is designated as a reference plane; the length of the circumferential trajectory formed when the airway support intersects with the reference plane is LZ; there are multiple intersection points formed when the airway support intersects with the reference plane, and the length of the line connecting the two farthest intersection points is LD; when the airway support intersects with the reference plane at any position, 50%LZ≤LD≤95%LZ.

[0020] In one embodiment, the airway support includes a plurality of wave coils connected in sequence, each wave coil being composed of a plurality of long rods and a plurality of short rods; at least some of the wave coils are flexible wave coils, each flexible wave coil including a flexible region and a standard region connected to each other, the flexible region including a plurality of long rods connected in sequence, the standard region including a plurality of long rods and short rods connected alternately, and the standard region being connected to the long rods of the flexible region through the short rods.

[0021] The beneficial effects of this invention are as follows: Addressing the clinical challenge of obstructing sputum expectoration after conventional airway stent implantation, this technical solution achieves a dual breakthrough in airway support and ciliary function protection through ingenious structural and mechanical design. Its beneficial effects are specifically reflected in the following aspects: First, from a microscopic anatomical perspective, after implantation, the airway stent does not simply float on the mucosal surface. Instead, it is partially "embedded" within the mucosal and submucosa of the tracheal wall by specific radial support forces. This embedding process creates an excellent state of physiological compatibility: the spiral structure of the airway stent becomes a "skeleton" within the airway wall, while the mucosal tissue on the surface of the airway wall migrates and heals to some extent over the gaps in the stent and the monofilament structure. At this point, the main stress point of the airway stent is located in the deep mucosa, while the height of the filament protruding above the mucosal surface is strictly controlled to an extremely low level. Since the length of airway epithelial cilia is typically 6-7 micrometers, the filament diameter of the airway stent in this design has been precisely calculated, and its height protruding above the mucosal surface is even lower than the length of the cilia themselves. As mentioned earlier, when the cilia make rapid and powerful forward strokes, their waving trajectory can easily overcome these low "micro-topographical obstacles." The mucus blanket can still advance continuously and completely above the airway support protrusions, just like in the sol layer in its natural state, thus perfectly maintaining the continuity and transport rhythm of the "ciliary-mucus blanket" system.

[0022] Secondly, this design cleverly resolves the inherent contradiction between physical support and biological rejection. The radial force of the airway stent is the cornerstone of ensuring airway patency. If the wire diameter is made infinitely thin solely to protect the cilia, the airway stent's support strength will inevitably be insufficient to counteract the recoil force of the narrowed airway segment. This solution deeply identifies this core conflict and achieves sufficient radial support force with an extremely thin wire diameter by optimizing the braiding structure and mechanical transmission of the airway stent. The small wire diameter reduces physical obstruction to the cilia, while the excellent structural mechanics design ensures that the airway stent acts like a miniature high-strength spring, uniformly and continuously acting on the airway wall, providing sufficient and lasting support to open the narrowed disease segment and resist tracheal collapse. This "thin yet strong" characteristic avoids the obstruction of expectoration caused by an excessively large wire diameter and eliminates the risk of airway collapse caused by an excessively small wire diameter, achieving a delicate balance between mechanics and physiology.

[0023] Furthermore, this low-protrusion design significantly reduces the excessive inflammatory response caused by the airway stent itself as a foreign body. Traditional coarse-wire airway stents have a high protrusion, which not only mechanically breaks and crushes cilia, but also generates significant shear force under the drag of the mucus blanket, continuously rubbing against the mucosal surface, inducing severe local edema, granulation tissue hyperplasia, and excessive mucus secretion, forming a vicious cycle of "increased secretions - obstructed drainage - airway stent blockage." However, when the airway stent is mostly embedded in the inner wall and has a very low protrusion, the dragging disturbance of airflow and mucus on the airway stent is greatly reduced, allowing the mucosa to heal in a relatively stable microenvironment. This stable interface greatly inhibits the excessive secretion of goblet cells, reducing the amount of sputum production at the source. Coupled with the intact ciliary movement and drainage function, it truly solves the stubborn problem of sputum accumulation and difficulty in clearing after airway stent implantation in a two-pronged approach. Attached Figure Description

[0024] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure provided in an embodiment of the present invention; Figure 2 This is a cross-sectional schematic diagram of the airway stent deployed into the trachea according to an embodiment of the present invention; Figure 3 This is a structural schematic diagram provided in Embodiment 12 of the present invention; Figure 4 This is a cross-sectional schematic diagram of the airway support intersecting with the reference plane in Embodiment 13 of the present invention; Figure 5 This is a schematic diagram of the deployed state of the airway stent when it intersects with the reference plane in Embodiment 13 of the present invention; Figure 6 This is a schematic diagram of the unfolded state provided in Embodiment 14 of the present invention; Figure 7 This is a diagram showing the relationship between the trough and the proximal end distance provided in an embodiment of the present invention; Figure 8 This is a diagram showing the angle relationship between the long and short rods and their length relationships, provided in an embodiment of the present invention. Figure 9 This is a diagram showing the distance relationship between peaks and valleys provided in an embodiment of the present invention.

[0026] The attached figures are labeled as follows: 100. Airway stent; 110. Peak; 120. Trough; 130. Long rod; 140. Short rod; 150. Junction point; 160. Flexible area; 170. Standard area; 190. Wave loop; 191. Sputum clearance channel; 200. Trachea; 210. Cilia; 300. Reference plane. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0028] The human trachea has cilia on its walls. The cilia on the surface of the tracheal mucosa beat rhythmically and directionally (towards the throat), pushing the mucus, dust, bacteria, foreign objects and other substances in the airway upwards. These are eventually expelled through coughing, forming a mucociliary clearance effect. However, after conventional stent implantation, the sputum is blocked by the stent and is difficult to expel.

[0029] To address the aforementioned technical difficulties, the present invention provides an airway stent 100, such as... Figure 1 As shown, its core feature is that the airway support 100 is a single-wire structure wound into a spiral shape. The wire diameter of the airway support 100 is 0.12-0.45 mm, and the ratio of the radial force of the airway support 100 to the wire diameter is 0.02-0.30 N / mm. 2 .

[0030] The airway stent 100 is generally made of a monofilament structure with a uniform diameter. Therefore, the filament diameter of the airway stent 100 refers to the diameter of the monofilament structure. If the airway stent 100 is made of a monofilament structure with uneven thickness, there are two cases: One type is a monofilament structure with a basically uniform overall diameter, with only a small portion having a diameter difference. This small portion will not affect sputum expectoration. In this case, the diameter of this small portion can be ignored, and the approximate diameter of the monofilament structure can be used as the diameter of the airway stent 100.

[0031] One possibility is that the difference in diameter of the monofilament structure can affect the expectoration process. In this case, the diameter of each part of the monofilament structure cannot be ignored. It is necessary to ensure that the size of the part with the largest diameter of the monofilament structure is appropriate and will not affect the expectoration process. Therefore, the maximum diameter of the monofilament structure should be used as the wire diameter of the airway stent 100.

[0032] In addition, the radial force of the airway stent 100 is one of its performance indicators, and the specific value can be obtained by the following measurement method: Step 1: Equipment and Fixture Preparation. The equipment can be a universal testing machine / compression testing machine, equipped with displacement and force sensors. The fixture consists of two parallel, smooth, rigid plates, the surface dimensions of which must completely cover the 100mm length of the airway support.

[0033] Step 2, clamping the airway support 100. Place the airway support 100 horizontally at the center of the lower plate, ensuring that the axis of the airway support 100 is parallel to the plate, without tilting or bending; the plate should cover the entire length or part of the length of the airway support 100. Adjust the position of the upper plate so that it lightly contacts the surface of the airway support 100, record the displacement at this point as zero, and reset the force value to zero; Step 3, Test: Set the compression speed to 50mm / min, start the testing machine, and stop the compression when the outer diameter of the airway support 100 is compressed to 50% of the initial outer diameter. Record the force value at this time.

[0034] Step 4, Data Processing: Calculate the radial force of the airway support 100 according to the formula: radial force = extrusion force F / effective length being extruded.

[0035] like Figure 2 As shown, when the airway stent 100 is installed in the trachea 200, a portion of the airway stent 100 will be embedded in the inner wall of the trachea 200, while the remaining portion will protrude out of the inner wall of the trachea 200. Since the wire diameter of the airway stent 100 is small, the protruding portion of the airway stent 100 will be shorter than the cilia 210 on the inner wall of the trachea 200, thus not hindering the movement of the cilia 210 to expel sputum. Moreover, by setting the airway stent 100 to have sufficient radial force, the situation where the trachea 200 cannot be opened due to the small wire diameter of the airway stent 100 is also avoided.

[0036] It should be noted that to achieve a radial force to wire diameter ratio of 0.02-0.30 N / mm for the airway support 100, 2 The main considerations are the wire diameter, material selection, radial dimension, and axial dimension of each component of the airway support 100. To provide more comprehensive support for the present invention, several embodiments will be provided below for detailed explanation.

[0037] I. Wire Diameter and Material Selection of Airway Stent 100 When selecting two dimensions as key elements in the design of the airway stent 100, the wire diameter and the material of the airway stent 100 can be considered as the main key elements. For example, the airway stent 100 can be made of metal, or it can be made of a combination of metal and biodegradable materials. Specifically, the airway stent 100 can be manufactured by a material weaving and heat setting method.

[0038] For a more specific description, the following embodiments will provide alternative materials for the airway stent 100, including nickel-titanium alloy, cobalt-chromium alloy, stainless steel, polyglycolic acid, polycaprolactone, poly-L-lactic acid, polydioxanone, and polylactic acid.

[0039] Example 1 At this time, the wire diameter of the airway support 100 is 0.18 mm. The airway support 100 is made of nickel-titanium alloy. After selecting this setting method, the ratio of the radial force of the airway support 100 to the wire diameter was measured to be 0.19 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0040] This embodiment utilizes a combination of an ultra-fine wire diameter (0.18 mm) and a highly elastic nickel-titanium alloy, suitable for moderate stenosis of the main trachea or main bronchus. The ultra-fine wire diameter ensures that the stent protrudes significantly below the mucosal length (approximately 6-7 μm), allowing the cilia to move freely without obstruction and minimal impact on sputum clearance. A radial force / wire diameter ratio of 0.19 N / mm² ensures sufficient radial support force, effectively counteracting the recoil force of the narrowed airway segment, achieving a "thin yet strong" clinical effect, making it particularly suitable for patients requiring long-term placement and with high sputum clearance requirements.

[0041] Of course, the airway support 100 is not limited to being made of nickel-titanium alloy; it can also be made of cobalt-chromium alloy, stainless steel, or other metallic materials. As long as the airway support 100 is made of a metallic material, and the wire diameter is 0.12-0.25 mm, the radial force to wire diameter ratio of the airway support 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0042] Example 2 At this time, the wire diameter of the airway support 100 is 0.2 mm. The airway support 100 is made of nickel-titanium alloy and poly-L-lactic acid. After selecting this setting method, the radial force to wire diameter ratio of the airway support 100 was measured to be 0.2 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0043] This embodiment employs a composite structure of metal and biodegradable materials, suitable for complex airway stenosis requiring strong support while minimizing long-term inflammatory responses. The nickel-titanium alloy provides immediate and stable high radial support (0.2 N / mm²), while the poly-L-lactic acid coating or blend reduces direct metal-to-mucosal contact in the early stages, decreasing granulation tissue formation and excessive mucus secretion. A 0.2 mm wire diameter ensures unobstructed sputum clearance. This approach is particularly suitable for patients with malignant stenosis and a long expected survival, or benign stenosis but with severe stenosis, achieving the triple goals of "strong support, mucosa-friendly, and unobstructed sputum clearance."

[0044] Nickel-titanium alloy and poly-L-lactic acid are not the only options. The material for the airway stent 100 can preferably be selected from nickel-titanium alloy, cobalt-chromium alloy, stainless steel, polyglycolic acid, polycaprolactone, poly-L-lactic acid, polydioxanone, and polylactic acid. In this case, as long as the wire diameter of the airway stent 100 is 0.15-0.3 mm, the radial force to wire diameter ratio of the airway stent 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0045] II. Selection of Wire Diameter and Diameter of Airway Stent 100 When selecting two dimensions as key elements in the design of the airway support 100, the wire diameter and the diameter of the airway support 100 can be considered as the main key elements. For example, the diameter of the airway support 100 can be set to 3-15mm.

[0046] Since the airway support 100 of the present invention is a single filament structure wound into a spiral shape, the shape of the airway support 100 is approximately a tube when it is not subjected to any external force. Therefore, the diameter of the airway support 100 refers to the outer diameter of this tubular shape of the airway support 100. Specific embodiments are described below.

[0047] Example 3 At this time, the wire diameter of the airway support 100 is 0.2 mm, and the diameter of the airway support 100 is 10 mm. After selecting this setting, the ratio of the radial force of the airway support 100 to the wire diameter was measured to be 0.21 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0048] This embodiment uses the stent diameter (10mm) as the core variable, suitable for moderate stenosis of the main or intermediate bronchus in adults. The 10mm diameter fits the physiological size of most adult main bronchuses, effectively dilating the narrowed segment while avoiding excessive stretching of the normal airway wall. A radial force / wire diameter ratio of 0.21 N / mm² combined with an ultra-fine 0.2mm wire diameter ensures ample support while minimizing stent protrusion and allowing sufficient space for ciliary movement. This parameter combination is a general solution for sputum-clearing-friendly stents in adult main bronchial stenosis.

[0049] Of course, the wire diameter and the overall diameter of the airway support 100 are not limited to the choices mentioned above. As long as the wire diameter of the airway support 100 is 0.12-0.45 mm and the diameter is 3-15 mm, the ratio of radial force to wire diameter of the airway support 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0050] III. Selection of wire diameter, material, and diameter of airway stent 100 When selecting three dimensions as key elements for the design of the airway support 100, the wire diameter, the material of the airway support 100, and the diameter of the airway support 100 can be considered as the main key elements. Specific embodiments are shown below.

[0051] Example 4 At this time, the wire diameter of the airway support 100 is 0.2 mm. The airway support 100 is made of nickel-titanium alloy and has a diameter of 9 mm. After selecting this setting method, the ratio of the radial force of the airway support 100 to the wire diameter was measured to be 0.21 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0052] This embodiment further reduces the diameter to 9mm based on the metal material, making it suitable for adults with narrow main bronchi or children and adolescents with bronchial stenosis. The 9mm diameter is more adaptable than 10mm, reducing excessive expansion stress on the airway walls. The superelasticity of the nickel-titanium alloy and the radial force / wire diameter ratio of 0.21 N / mm² ensure excellent anti-collapse capability even with a smaller diameter. The 0.2mm wire diameter consistently ensures unobstructed sputum drainage. This solution is an ideal choice for sputum drainage stents in narrow-diameter main bronchial stenosis.

[0053] Of course, the airway support 100 is not limited to being made of nickel-titanium alloy; it can also be made of cobalt-chromium alloy, stainless steel, or other metallic materials. As long as the airway support 100 is made of a metallic material, and the wire diameter is 0.12-0.25 mm, and the overall diameter is 3-15 mm, then the radial force to wire diameter ratio of the airway support 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0054] Example 5 At this time, the wire diameter of the airway support 100 is 0.22 mm. The airway support 100 is made of nickel-titanium alloy and poly-L-lactic acid, and its diameter is 9 mm. After selecting this setting method, the radial force to wire diameter ratio of the airway support 100 was measured to be 0.22 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0055] This embodiment employs a composite structure with a 9mm diameter, suitable for patients with main bronchial stenosis and significant inflammatory response or a tendency for granulation tissue formation. The biodegradable coating of the composite material forms a protective barrier in the early stages of implantation (1-3 months), reducing direct irritation of the inflamed mucosa by the metal. The high radial force / filament diameter ratio of 0.22 N / mm² combined with the 0.22mm fine filament diameter achieves a synergistic effect of "high support + low irritation + smooth sputum clearance." This approach is the preferred choice for patients with inflammatory airway stenosis or those prone to granulation tissue formation.

[0056] Nickel-titanium alloy and poly-L-lactic acid are not the only options. The material for the airway stent 100 can preferably be selected from nickel-titanium alloy, cobalt-chromium alloy, stainless steel, polyglycolic acid, polycaprolactone, poly-L-lactic acid, polydioxanone, and polylactic acid. In this case, as long as the wire diameter of the airway stent 100 is 0.15-0.28 mm and the diameter of the airway stent 100 is 3-15 mm, the radial force to wire diameter ratio of the airway stent 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0057] IV. Selection of Wire Diameter and Axial Dimensions of Airway Support 100 When selecting two dimensions as key design elements for the airway support 100, the wire diameter and the axial dimensions of the components of the airway support 100 can be considered as the main key elements, such as... Figure 1 As shown, the airway support 100 of the present invention includes a plurality of corrugated coils 190, which are interconnected in a spiral shape. The axial dimension of the corrugated coils 190 (i.e., Figure 1 The distance between the top and bottom of the wave circle 190 shown is 7-20mm.

[0058] Specifically, the wave coil 190 is a monofilament structure wound into an approximately loop shape, and the two ends of the wave coil 190 extend to the distal and proximal ends of the airway support 100, respectively, so that the wave coil 190 has a certain axial length. Moreover, the axial direction of the wave coil 190 is consistent with the axial direction of the airway support 100 in the straightened state. Therefore, the axial dimension of the wave coil 190 refers to its length dimension that is consistent with the axial direction of the airway support 100. Specific embodiments are described below.

[0059] Example 6 At this time, the wire diameter of the airway support 100 is 0.18 mm, and the airway support 100 includes multiple corrugated coils 190, which are interconnected in a spiral shape. The axial dimension of the corrugated coil 190 is 15 mm. After selecting this setting, the ratio of the radial force to the wire diameter of the airway support 100 is measured to be 0.18 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0060] This embodiment uses the axial dimension of the stent coil (15mm) as the core variable, and is suitable for long-segment airway stenosis or lesions requiring axial stability support (such as multi-segment tracheal stenosis). The larger axial dimension of the stent coil (15mm) allows for more uniform axial coverage, avoiding local stress concentration and "concave" effects, while adjacent coils naturally separate to form a spiral-shaped sputum clearance channel. The wire diameter of 0.18mm maintains extremely low protrusion. This parameter combination is particularly suitable for cases with stenosis length >30mm, achieving "long-segment support + full-area sputum clearance".

[0061] Of course, the wire diameter of the airway support 100 and the axial dimension of the corrugated coil 190 are not limited to the above choices. As long as the wire diameter of the airway support 100 is 0.12-0.45mm, and the airway support 100 includes multiple corrugated coils 190 connected in a spiral shape, with the axial dimension of the corrugated coil 190 being 7-20mm, the radial force to wire diameter ratio of the airway support 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0062] V. Selection of wire diameter, material, and axial dimension of airway support 100 and bellows 190. When selecting three dimensions as key elements for the design of the airway support 100, the wire diameter of the airway support 100, the material of the airway support 100, and the axial dimension of the wave coil 190 can be considered as the main key elements. Specific embodiments are shown below.

[0063] Example 7 At this time, the wire diameter of the airway support 100 is 0.19 mm. The airway support 100 is made of nickel-titanium alloy, and the axial dimension of the bellows 190 is 15 mm. After selecting this setting, the ratio of the radial force to the wire diameter of the airway support 100 was measured to be 0.18 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0064] This embodiment utilizes a combination of metallic materials and a large coil size (15mm), suitable for lesions with long-segment stenosis of the main trachea requiring strong radial support (such as malignant stenosis and external compression stenosis). The nickel-titanium alloy provides stable and high-strength support, while the 15mm coil axial dimension ensures that the stent will not excessively shift or collapse axially due to respiratory dynamics. The 0.19mm wire diameter ensures sufficient space for ciliary movement. This design is a preferred option for sputum drainage stents for long-segment malignant stenosis of the main trachea.

[0065] Of course, the wire diameter of the airway support 100, the material of the airway support 100, and the axial dimension of the bellows 190 are not limited to the choices mentioned above. As long as the wire diameter of the airway support 100 is 0.12-0.25mm, the airway support 100 is made of nickel-titanium alloy, cobalt-chromium alloy, stainless steel, etc., and the axial dimension of the bellows 190 is 12-20mm, the radial force to wire diameter ratio of the airway support 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0066] Example 8 At this time, the wire diameter of the airway support 100 is 0.19 mm. The airway support 100 is made of nickel-titanium alloy and poly-L-lactic acid. The axial dimension of the corrugated coil 190 is 15 mm. After selecting this setting, the ratio of the radial force to the wire diameter of the airway support 100 was measured to be 0.18 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0067] This embodiment employs a composite structure combined with a large coil size (15mm), suitable for patients with long-segment stenosis of the main trachea or main bronchus accompanied by mucosal irritation (such as post-radiotherapy stenosis or stenosis after repeated stent placement). The biodegradable coating of the composite material reduces metal irritation to the fragile mucosa, the 15mm coil size provides axial stability, and the 0.19mm fine wire diameter ensures unobstructed sputum clearance. This approach is an ideal choice for the retreatment of complex airway stenosis.

[0068] Nickel-titanium alloy and poly-L-lactic acid are not the only options. The material for the airway stent 100 can preferably be selected from nickel-titanium alloy, cobalt-chromium alloy, stainless steel, polyglycolic acid, polycaprolactone, poly-L-lactic acid, polydioxanone, and polylactic acid. In this case, as long as the wire diameter of the airway stent 100 is 0.15-0.28 mm and the axial dimension of the corrugated coil 190 is 12-20 mm, the radial force to wire diameter ratio of the airway stent 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0069] VI. Selection of wire diameter, diameter of airway support 100, and axial dimension of corrugated coil 190. When selecting three dimensions as key elements for the design of the airway support 100, the wire diameter of the airway support 100, the diameter of the airway support 100, and the axial dimension of the wave coil 190 can be considered as the main key elements. Specific embodiments are shown below.

[0070] Example 9 At this time, the wire diameter of the airway support 100 is 0.19 mm, the diameter of the airway support 100 is 8 mm, and the axial dimension of the bellows 190 is 15 mm. After selecting this setting, the ratio of the radial force of the airway support 100 to the wire diameter is measured to be 0.15 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0071] This embodiment achieves synergistic optimization of three parameters: wire diameter, overall diameter, and bevel coil size. It is suitable for routine cases of moderate stenosis in adult main bronchus requiring a comprehensive balance between support and sputum clearance. The 8mm diameter fits most main bronchi, the 15mm bevel coil size ensures axial stability, and the 0.19mm wire diameter ensures ciliary movement. The radial force / wire diameter ratio of 0.15 N / mm² provides sufficient but not excessive support, avoiding damage to the airway wall. This design is the "standard configuration" for sputum clearance stents in adult main bronchus stenosis and has the widest applicability.

[0072] Of course, the wire diameter of the airway support 100, the diameter of the airway support 100, and the axial dimension of the bellows 190 are not limited to the choices mentioned above. As long as the wire diameter of the airway support 100 is 0.12-0.45mm, the diameter of the airway support 100 is 3-15mm, and the axial dimension of the bellows 190 is 7-20mm, the radial force to wire diameter ratio of the airway support 100 can be satisfied to be 0.02-0.30N / mm. 2 The demand.

[0073] VII. Selection of wire diameter, material, diameter, and axial dimension of airway support 100 and bellows 190 of airway support 100. When selecting four dimensions as key elements for the design of the airway support 100, the wire diameter of the airway support 100, the material of the airway support 100, the diameter of the airway support 100, and the axial dimension of the wave coil 190 can be considered as the main key elements. Specific embodiments are shown below.

[0074] Example 10 At this time, the wire diameter of the airway support 100 is 0.17 mm. The airway support 100 is made of nickel-titanium alloy and has a diameter of 10 mm. The axial dimension of the bellows 190 is 15 mm. After selecting this setting, the ratio of the radial force to the wire diameter of the airway support 100 is measured to be 0.18 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0075] This embodiment uses a combination of an extremely fine wire diameter (0.17 mm) and a large diameter (10 mm) and large coil size (15 mm), suitable for patients with moderate to severe stenosis of the main trachea and extremely high requirements for sputum clearance (such as those with underlying conditions such as chronic bronchitis, COPD, etc., that impair sputum clearance). 0.17 mm is the finest wire diameter currently available, with minimal protrusion from the mucosa and virtually no obstruction to ciliary movement. The radial force / wire diameter ratio of 0.18 N / mm² compensates for any potential loss of support force due to the extremely fine wire diameter through the use of metal materials and structural design. This approach is an "ultimately sputum-clearing-friendly" airway stent, particularly suitable for patients with impaired sputum clearance function.

[0076] Of course, the wire diameter, material, and diameter of the airway support 100, as well as the axial dimension of the bellows 190, are not limited to the choices mentioned above. As long as the wire diameter of the airway support 100 is 0.12-0.25mm, the airway support 100 is made of nickel-titanium alloy, cobalt-chromium alloy, stainless steel, etc., the diameter of the airway support 100 is 3-15mm, and the axial dimension of the bellows 190 is 12-20mm, the radial force to wire diameter ratio of the airway support 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0077] Example 11 At this time, the wire diameter of the airway support 100 is 0.19 mm. The airway support 100 is made of nickel-titanium alloy and poly-L-lactic acid. The diameter of the airway support 100 is 11 mm, and the axial dimension of the bellows 190 is 15 mm. After selecting this setting, the ratio of the radial force to the wire diameter of the airway support 100 was measured to be 0.2 N / mm. 2 This satisfies the requirement that the radial force to wire diameter ratio of the airway support 100 is 0.02-0.30 N / mm. 2 The demand.

[0078] This embodiment employs a composite structure with a larger diameter (11mm) and a larger coil size (15mm), suitable for patients with severe stenosis of the main trachea or main bronchus and a relatively large diameter (e.g., adult males with main tracheal stenosis). The 11mm diameter is adapted to the large-sized main trachea, and the high radial force / wire diameter ratio of 0.2 N / mm² provides the strong support required to combat severe stenosis. The biodegradable coating of the composite material reduces the risk of mucosal irritation caused by strong support. The 0.19mm wire diameter ensures unobstructed sputum drainage even under strong support. This approach is the optimal choice for sputum drainage stents for patients with severe stenosis of the large-diameter main trachea.

[0079] Nickel-titanium alloy and poly-L-lactic acid are not the only options. The material for the airway stent 100 can preferably be selected from nickel-titanium alloy, cobalt-chromium alloy, stainless steel, polyglycolic acid, polycaprolactone, poly-L-lactic acid, polydioxanone, and polylactic acid. In this case, as long as the wire diameter of the airway stent 100 is 0.15-0.3 mm, the diameter of the airway stent 100 is 3-15 mm, and the axial dimension of the corrugated coil 190 is 12-20 mm, the radial force to wire diameter ratio of the airway stent 100 can be satisfied to be 0.02-0.30 N / mm. 2 The demand.

[0080] VIII. Further optimization of sputum expectoration function Example 12 like Figure 3 As shown, the airway stent 100 includes multiple coils 190, which are interconnected in a spiral shape. Adjacent coils 190 are separated to form a sputum clearance channel 191, which is arranged in a spiral shape on the airway stent 100.

[0081] Figure 3 This is a diagram showing the state of wave loops 190 when they are extended and arranged in a plane. As can be seen from the diagram, adjacent wave loops 190 are completely separated. The peaks 110 and troughs 120 of adjacent wave loops 190 are staggered. The area where the peaks 110 and troughs 120 of adjacent wave loops 190 are separated forms the sputum drainage channel 191.

[0082] With this setup, there is always an unobstructed sputum drainage channel 191 between adjacent wave loops 190. As the cilia on the tracheal wall move against each other, sputum can be discharged directly and smoothly along the sputum drainage channel 191, avoiding mucus retention.

[0083] Moreover from Figure 3It can be seen that the peaks 110 and troughs 120 of each wave loop 190 are arranged on two straight tracks, which are the wave loop peak 110 arrangement track and the wave loop trough 120 arrangement track, respectively. The distance between the wave loop peak 110 arrangement track and the wave loop trough 120 arrangement track is the width L1 of the wave loop 190, and the distance between the wave loop trough 120 arrangement track and the wave loop peak 110 arrangement track of adjacent wave loops 190 is the width L2 of the sputum drainage channel 191. At this time, the width L1 of the wave loop 190 can be set to 2-6mm, preferably 3-5mm.

[0084] It should be noted that the wider the wave 190 is, the larger the coverage area of ​​the wave 190 will be, but an excessively large coverage area of ​​the wave 190 will affect the clearance of mucus; while the narrower the width of the wave 190, the smaller the support area of ​​the airway support 100 will be, resulting in a poorer support effect.

[0085] Therefore, in order to achieve a balance between the two, the ratio of the width L2 of the spiral sputum drainage channel 191 to the width L1 of the wave loop 190 can be set to 0.6-0.9, and preferably 0.7-0.8, so as to achieve a better balance between the two.

[0086] IX. Further optimization of support performance Example 13 Please see Figure 1 , Figure 4 and Figure 5 This embodiment provides an airway stent 100. The airway stent 100 is formed by spirally winding a continuous medical monofilament (preferably a nickel-titanium shape memory alloy wire), and has an overall hollow cylindrical or roughly cylindrical structure. Its axial length is set according to clinical needs.

[0087] The airway support 100 includes multiple peaks 110 and multiple troughs 120, which are arranged alternately along a spiral trajectory. That is, along the spiral direction, the sequence is peak 110 → trough 120 → peak 110 → trough 120… and so on. The peaks 110 and troughs 120 together constitute the basic support unit of the airway support 100.

[0088] To quantitatively describe the coverage characteristics of the airway stent 100 on any cross-section, the following definitions are introduced in this embodiment: Let a plane perpendicular to the axial direction of the airway support 100 be the reference plane 300 (i.e., the cross-section). When the airway support 100 intersects with the reference surface 300, the total length of all trajectory segments formed by the filaments of the airway support 100 on the reference surface 300 is the circumferential trajectory length, denoted as LZ.

[0089] When the airway support 100 intersects with the reference surface 300, multiple intersection points 150 are formed (i.e., the intersection points formed by the reference surface 300 cutting the support wires). The length of the line connecting the two intersection points 150 that are furthest apart is denoted as LD.

[0090] Since the airway support 100 is arranged along a spiral trajectory, the two furthest intersection points 150 refer to the two intersection points 150 that are furthest apart along this spiral trajectory. For example, assuming... Figure 5 The spiral trajectory extends from left to right, so the two intersection points 150 on the far left and the left and right sides are the two intersection points 150 that are farthest apart.

[0091] In this embodiment, when the airway support 100 intersects the reference surface 300 at any position (i.e., taking any cross-section along the axial direction), 50%LZ ≤ LD ≤ 95%LZ. Testing showed that when LD / LZ is below 50%, the intersection point 150 is too concentrated, resulting in insufficient radial support; when it is above 95%, the circumferential coverage is too long, easily leading to over-coverage. This embodiment controls the ratio between 50% and 95%, achieving a balance between support force and coverage area.

[0092] Preferably, when the reference plane 300 intersects the airway stent 100 at any position, 60%LZ ≤LD ≤ 90%LZ, in order to further optimize the clinical effect.

[0093] 10. Optimization of the safety performance of the airway stent 100 Example 14 Please see Figure 1 and Figure 6 This embodiment optimizes the structure of the airway support 100, making it adaptable to the aforementioned embodiments. In this embodiment, the airway support 100 includes multiple wave coils 190 connected in sequence (the waveform of any point of the airway support 100 around a circle is a wave coil 190, and each wave coil 190 is recommended to have at least three sets of peaks 110 and troughs 120). Each wave coil 190 is formed by connecting multiple long rods 130 and multiple short rods 140. At least some of the wave coils 190 are flexible wave coils, each of which includes a flexible region 160 and a standard region 170 connected to each other. The flexible region 160 includes multiple long rods 130 connected in sequence, and the standard region 170 includes multiple long rods 130 and short rods 140 connected alternately. The standard region 170 is connected to the long rods 130 of the flexible region 160 through the short rods 140.

[0094] It should be noted that in the aforementioned embodiments, multiple wave coils 190 are connected sequentially, and the wave coils 190 can be arranged by alternating long and short rods; however, the main difference in this embodiment is that at least some of the wave coils 190 are flexible wave coils, and the flexible wave coils are no longer arranged by alternating long and short rods.

[0095] Specifically, in the flexible region 160 of the flexible wave coil, instead of alternating long rods 130 and short rods 140, multiple long rods 130 are connected to each other to form a certain number of peaks 110 and valleys 120 to form the flexible region 160. Then, a short rod 140 is used to connect with the standard region 170. The standard region 170 is formed by alternating long and short rods to form a certain number of peaks 110 and valleys 120. Thus, the flexible wave coil presents a new arrangement method, changing from sequentially connecting multiple long rods 130 to alternating connecting long and short rods.

[0096] The advantage of the above-mentioned arrangement is that it can maintain the monofilament braided structure of the airway stent 100 and make the airway stent 100 more flexible. During the process of the airway stent 100 being released from the outer sheath, the radial rebound force of the airway stent 100 will cause the released part to bounce back against the tracheal wall. The bounced part will form an angle with the central axis of the airway stent 100. The shorter the side rod (i.e., the long rod 130 or the short rod 140), the larger the angle. The more perpendicular the released peak 110 or trough 120 is to the tracheal wall, the more likely it will bounce against the tracheal wall after the side rod is fully released. Therefore, the setting of the short rod 140 may increase the damage to the tracheal wall.

[0097] The above-mentioned arrangement can increase the number of long rods 130 and reduce the number of short rods 140. Since the ejection direction of the long rod 130 has a small angle with the tracheal wall, it causes less damage to the tracheal wall. Therefore, by continuously arranging multiple long rods 130, the overall stability of the airway support 100 can be maintained. By using short rods 140 for connection, the flexibility and compliance of the airway support 100 can be maintained. Thus, during the release process of the peak 110 and trough 120, it is always constrained by at least one long rod 130, reducing damage to the tracheal wall during the release process.

[0098] It should be noted that the number of long rods 130 in the flexible region 160 should not be too many or too few. It is recommended that the number of long rods 130 in the flexible region 160 be 3-6. For example, in this embodiment, 3 long rods 130 are connected in sequence to form the flexible region 160.

[0099] Because in the flexible region 160, if the number of long rods 130 is too small (e.g., 1-2 rods), the flexibility improvement is not obvious; if the number is too large (e.g., more than 6 rods), the airway support 100 will be too soft in some areas, which may affect the continuity of the radial support force, or even cause the airway support 100 to collapse or shift in narrow areas.

[0100] By limiting the number of long rods 130 in the flexible region 160 to 3-6, it ensures that the flexible region 160 has sufficient bending compliance, while maintaining the overall structural stability of the airway support 100 and the integrity of the support force transmission path, thus avoiding problems such as "excessive flexibility" or "abrupt stiffness".

[0101] Similarly, the coverage of the flexible region 160 should also be limited to a certain extent. It is generally recommended that the number of long rods 130 in the flexible region 160 be 35%-65% of the total number of long and short rods in the flexible wave coil.

[0102] If the number of long rods 130 in the flexible region 160 is too low (<35%), the airway stent 100 will be too rigid overall, making it difficult to adapt to complex or curved airway anatomy, increasing the difficulty of release and the risk of mucosal damage; if the number of long rods in the flexible region 160 is too high (>65%), the overall support of the airway stent 100 will decrease, and it may not be able to effectively resist the collapse force of the narrowed area.

[0103] By controlling the proportion of long rods 130 in the flexible region 160 to between 35% and 65%, the axial flexibility and release safety of the airway stent 100 can be significantly improved while maintaining the overall radial support force, making it suitable for most lesion scenarios from the trachea to the main bronchus.

[0104] Furthermore, when setting up the flexible wave coil, it is recommended that the flexible wave coil be placed at least at the proximal and / or distal end of the airway support 100.

[0105] The proximal (near the oral cavity) and distal (distal) ends of the airway stent 100 are prone to relative movement with the airway wall after implantation, especially during breathing, coughing, or swallowing. If these areas are too rigid, it can easily lead to mucosal abrasion, granulation tissue hyperplasia, or even perforation.

[0106] By incorporating flexible corrugations at these ends, the dynamic impact force of the airway stent 100 on the airway can be effectively buffered, reducing local pressure and friction damage. Simultaneously, the flexible ends are more likely to collapse and separate from the airway wall during removal, reducing the difficulty of removal and the risk of complications.

[0107] XI. Other optional optimization methods Furthermore, the above embodiments can also be improved in the following ways: 1. An oxide layer or titanium nitride coating can be applied to the surface of the airway stent 100 to prevent the release of nickel ions, which can stimulate granulation tissue growth. Furthermore, silicone, poly(L-lactic acid) or polycaprolactone can be applied to the surface to reduce direct metal irritation to the tracheal wall.

[0108] 2. For example Figure 1 As shown, smooth portions 180 can be provided at both ends of the airway support 100. The smooth portions 180 have a smooth surface and their cross-section is larger than that of other parts. The material can be nickel-titanium alloy, silicone, silicone, poly(L-lactic acid) polycaprolactone, poly(p-dioxanone), polylactic acid, polyglycolic acid, etc. When the smooth portion 180 is a nickel-titanium alloy, it can be formed by laser welding. When the smooth portion 180 is made of other materials, it can be formed by fusion or other processes. After the smooth portions 180 are provided, the ends of the airway support 100 can be prevented from damaging the tracheal wall.

[0109] 3. When manufacturing the airway support 100, a monofilament spiral weaving method can be used to form high and low waveforms to ensure that the axially adjacent peaks 110 and troughs 120 are unrestrained and in contact, allowing for flexible axial movement and providing strong axial flexibility and tensile strength.

[0110] Moreover, this configuration allows the airway support 100 to move with the airway, reducing friction between the airway support 100 and the airway wall that could lead to granulation tissue growth. In addition, if granulation tissue covers the airway support 100, the airway support 100 can deform in a straight line along the axial direction once it is subjected to axial force, thus facilitating the removal of the airway support 100.

[0111] 4. Since the airway stent 100 is made of monofilament spiral braiding, its overall shape is similar to a tube. In this case, it is advisable to set the proximal end of the airway stent 100 as a constricted structure. That is, in the axial direction towards the proximal end of the airway stent 100, the diameter of the proximal end of the airway stent 100 decreases. Specifically, the length of the constriction can be set to 2-8mm, and the diameter of the constriction can be set to 0.7-0.9 of the bronchial diameter. After adopting this setting, the proximal part of the airway stent 100 can be separated from the tracheal wall, which makes it easier to grasp the proximal end of the airway stent 100.

[0112] 5. As can be seen from the above, the airway stent 100 is formed by connecting the long rod 130 and the short rod 140 in a specific manner. Here, the long rod 130 and the short rod 140 can be collectively referred to as side rods. Therefore, there must be an initial side rod at the proximal end of the airway stent 100. The starting end of this initial side rod may extend from the distal end to the proximal end of the airway stent 100, or it may extend from the proximal end to the distal end of the airway stent 100.

[0113] In the specific design, it is recommended to set the starting side rod to extend from the proximal end to the distal end of the airway support 100 to ensure that the starting end of the starting side rod is located close to the proximal end of the airway support 100. Because with this setting, if it is necessary to pull the proximal end of the airway support 100, the force direction of the starting side rod will be basically consistent with the tensile direction of the airway support 100, which facilitates the transmission of tensile force to the subsequent side rods, making it easier to pull the airway support 100.

[0114] Furthermore, it is preferable to set the starting side rod as a long rod 130 and the second side rod connected to the starting side rod as a short rod 140. In this case, once the starting side rod is captured and pulled, the second side rod is the first side rod that needs to be deformed. At the same angle, the short rod 140 is more likely to be deformed and straightened, which makes it easier to remove the airway support 100.

[0115] 6. The distal end of the airway support 100 can be set as a waveform with equal height, in which case the height of the distal short rod 140 is approximately equal to the height of the long rod 130. With this setting, once the distal end of the airway support 100 is released, the waveform with equal height can be evenly anchored on the tracheal wall in a circular manner, which facilitates the gradual release of subsequent waveforms and prevents deformation during the release process.

[0116] At this time, the middle part and the proximal end can maintain the height bar setting so that when the airway support 100 is grasped and pulled, the proximal end of the airway support 100 can be more easily deformed and straightened, thus facilitating removal.

[0117] 7. When designing the airway support 100, it is recommended that at least one trough 120 in each wave 190 has a greater distance to the proximal end of the airway support 100 than the distances of other troughs 120 to the proximal end. This setting will allow the airway support 100 to naturally form a single-filament braided structure. In this case, the distances of other troughs 120 to the proximal end can be equal or unequal, and the distances of other peaks 110 to the proximal end can also be equal or unequal.

[0118] For example from Figure 7 It can be seen that, at this point, it is preferable to set each adjacent trough 120 to be the right trough 120 to the near end (i.e., Figure 7 The distance between the upper part of the wave 110 and the upper part of the wave 110 is greater. The adjacent wave 110 is closer to the right side. This setting allows each wave to be rotated to the right relatively evenly to form the airway support 100.

[0119] By setting at least one trough 120 in each wave 190 with a distance from the proximal end greater than that of other troughs 120, and by making the axial distance of adjacent troughs 120 increase sequentially, an asymmetrical peak 110-trough 120 arrangement structure can be formed. This improves the wall compliance of the airway stent 100 in the curved airway, enhances the positioning controllability during release, and guides the airway stent 100 to gradually collapse along the spiral path during removal, thereby reducing removal resistance and the risk of mucosal damage.

[0120] 8. For example Figure 8 As shown, when designing the airway support 100, the angle between the long rod 130 and the central axis of the airway support 100 can be set to C°, and the angle between the short rod 140 and the central axis of the airway support 100 can be set to D°, where C° < D°, and the height h1 of the short rod 140 / the height h2 of the long rod 130 is 0.5-1.

[0121] Because in the traditional equal-height side bar design, adjacent side bars are subjected to uniform force and deform synchronously, the connection between the peak 110, the trough 120 and the side bar is prone to forming fixed stress high points. In the long-term dynamic stress environment of tracheal breathing contraction, repeated fatigue traction can easily lead to the breakage of nickel-titanium wire and the deformation and failure of the stent.

[0122] This design breaks the force symmetry of a structure with equal height by using staggered arrangement of long and short rods. This allows the overall force of the airway support 100 to be distributed and transmitted along the long and short rods of different heights instead of being concentrated at a single connection point, thus significantly reducing local stress peaks.

[0123] Meanwhile, the buffer space formed by the height difference between the long and short rods can effectively offset the instantaneous impact force brought about by the dynamic contraction of the lumen, reduce the fatigue wear of the nickel-titanium wire, significantly improve the fatigue resistance and long-term implantation stability of the airway stent 100, and avoid serious complications such as breakage and collapse of the airway stent 100.

[0124] Furthermore, the trachea is not a straight, rigid tube, but a flexible structure with natural curves and physiological functions; therefore, by adopting a waveform design with alternating long and short rods, the airway stent 100 can better conform to the physiological curvature of the trachea in three-dimensional space.

[0125] When the airway stent 100 is assembled with the delivery device outer sheath, the circumferentially compressed airway stent 100 needs to be assembled into the delivery device outer sheath. The circumferentially compressed airway stent 100 causes the side rods to overlap, and the wave-like structure of the long and short rods reduces the overlap volume, making it easier for the airway stent 100 to be assembled into the outer sheath, or to be assembled into a smaller outer sheath, which is beneficial for delivering the airway stent 100 to a more distal bronchus for treatment.

[0126] 9. For example Figure 9As shown, when designing the airway support 100, it is also possible to set the lowest peak 110 to the proximal end (i.e., ...) in each wave ring 190. Figure 9 The distance above (as shown) is greater than the distance from the highest trough 120 to the near end, and the axial distance between the two is d=0.5-4mm, preferably 1-3mm.

[0127] Ensure that the airway stent 100 has a certain degree of flexibility to adapt to different tracheal structures; at the same time, when the airway stent 100 is compressed and assembled into the outer sheath, reduce the stacking of the airway stent 100 in the circumferential direction, reduce the assembly difficulty, or use a smaller outer sheath to assemble the airway stent 100.

[0128] 10. The outer contour of the airway stent 100 can be set to a tapered structure. Because the deeper the bronchus, the smaller the diameter of the bronchus, the larger the proximal diameter of the airway stent 100 is set to match the change in bronchial diameter with the extension structure. In this case, the proximal diameter / distal diameter of the airway stent 100 can be set to 1-2.5, and preferably 1.1-1.6.

[0129] 11. The airway stent 100 can be made of materials with good elasticity and biocompatibility to achieve the self-expansion performance of the airway stent 100, that is, it can expand and anchor itself to the bronchus by its own elasticity. For example, it can be made of nickel-titanium alloy, poly-L-lactic acid, polycaprolactone, polydioxanone, polylactic acid, polyglycolic acid, etc. Preferably, it is made of one or more biodegradable materials such as poly-L-lactic acid, polycaprolactone, polydioxanone, polylactic acid, polyglycolic acid, etc., which can degrade and be excreted from the body within a period of time, reducing complications such as granulation tissue hyperplasia caused by prolonged retention in the body.

[0130] When the airway support 100 is formed by weaving and heat setting of the above materials, it is recommended to set the wire diameter to 0.1-0.6 mm, preferably 0.1-0.2 mm.

[0131] 12. Antiproliferative agents, such as sirolimus, everolimus, zotamolimus, paclitaxel, tazocin, mitomycin, etc., can be coated on the surface of the airway stent 100, or anti-mucus agents, such as atropine, ipratropium or steroids, can be coated on the surface of the airway stent 100.

[0132] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. An airway stent, characterized in that, The airway support is a monofilament structure wound into a spiral shape. The diameter of the airway support is 0.12-0.45 mm, and the ratio of the radial force to the wire diameter is 0.02-0.30 N / mm. 2 .

2. The airway stent according to claim 1, characterized in that, The airway support is made of metal. Alternatively, the airway stent may be made of a combination of metal and biodegradable materials.

3. The airway stent according to claim 1, characterized in that, The wire diameter of the airway support is 0.12-0.25 mm; The airway support is made of metal.

4. The airway stent according to claim 1, characterized in that, The wire diameter of the airway support is 0.15-0.3 mm; The airway stent is made of a combination of metal and biodegradable materials.

5. The airway stent according to any one of claims 1 to 4, characterized in that, The diameter of the airway support is 3-15mm.

6. The airway stent according to any one of claims 1 to 4, characterized in that, The airway support includes multiple corrugated coils, which are interconnected in a spiral shape, and the axial dimension of each corrugated coil is 7-20 mm.

7. The airway stent according to any one of claims 1 to 4, characterized in that, The diameter of the airway support is 3-15mm; The airway support includes multiple corrugated coils, which are interconnected in a spiral shape, and the axial dimension of each corrugated coil is 7-20 mm.

8. The airway stent according to claim 1, characterized in that, The airway stent includes multiple wave coils, which are interconnected in a spiral shape. Adjacent wave coils are separated to form a sputum clearance channel, which is arranged in a spiral shape on the airway stent.

9. The airway stent according to claim 8, characterized in that, The ratio of the width of the spiral sputum drainage channel to the width of the wave is 0.6-0.

9.

10. The airway stent according to claim 1, characterized in that, The airway support includes multiple peaks and multiple troughs, and the multiple peaks and multiple troughs are arranged alternately along a spiral trajectory. Let a plane perpendicular to the axial direction of the airway support be a reference plane; The length of the circumferential trajectory formed when the airway support intersects with the reference plane is LZ; There are multiple intersection points formed when the airway support intersects with the reference plane, and the length of the line connecting the two intersection points that are furthest apart is LD; When the airway support intersects the reference plane at any position, 50%LZ≤LD≤95%LZ.

11. The airway stent according to claim 1, characterized in that, The airway support includes multiple wave coils connected in sequence, and each wave coil is composed of multiple long rods and multiple short rods connected together. At least some of the waveguides are flexible waveguides, each of which includes interconnected flexible regions and standard regions. Each flexible region includes multiple long rods connected in sequence, and each standard region includes multiple alternating long rods and short rods. The standard region is connected to the long rods of the flexible region through the short rods.

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