Patent Description:
It is well known that stents can be used to hold, open or enlarge body structures such as veins, arteries, ureters, urethras, hollow-body organs, nasal passages, sinus cavities, and the like.

There are many folds inside the nasal cavity. The shape of the nasal cavity is variable. The individual differences of the nasal cavity are very large. The complexity of the internal space of the nasal cavity is further aggravated if there is a lesion. In fact, the internal space of the nasal cavity may be as a cone, a trapezoidal body, a rhomboid, an ellipsoid or a sphere, or a variation and combination thereof, or even an irregular body. <CIT> discloses a stent, which is capable of biodegrading, and has a first compressed configuration enabling low profile delivery through a delivery device and a second expanding configuration for apposition against tissue. Specifically, the stent comprises at least one filament, which is formed into a shape having a series of peaks and valleys, and the shape approximates a repeating diamond-shaped pattern. At least one of the peaks and valleys has a loop at an end thereof, which is formed by winding the at least one filament. <CIT> is directed to medical implants/stents and system. Some embodiments of <CIT> include a self-expanding stent having a tabular first wall structure of a first diameter, where each end portion of the first wall structure is formed into a second wall structure of a second diameter larger than the first diameter. A membrane covers at least the first wall structure and the stent includes an interlaced, helicoidally wound wire forming a mesh-like structure.

<CIT> describes a method for making medical implant with open-work structure comprising the step consisting in forming the structure from a single wire, by running each strand of wire helicoidally from one end to the other of the structure and by interlacing this strand with other strands previously arranged. Said method moreover comprises the steps consisting in:-forming a loop between each strand at each end of the structure and setting the free ends of the first and of the last strand significantly back from the ends of the structure. <CIT> discloses a mandrel for manufacturing a stent from a single wire that includes a cylindrical member having a plurality of pins at a proximal end region, a plurality of pins at a distal end region, and a plurality of indentations between the proximal pins and the distal pins. These indentations form a helical pattern on the outer surface of the cylindrical member. The single wire is wrapped around every proximal pin and distal pin on the mandrel by following the indentations in the mandrel. The single wire is slid through the indentation under any crossing section of wire and over the next crossing section of wire in an under-over pattern.

Studies show that the stent of above patent is generally in the shape of a diamond or a crown in the second expanding configuration, and its cross section is limited to an approximately circular shape. Although it can be effectively applied to the blood circulation system, it cannot be adapted to the ever-changing internal space of the nasal cavity, resulting in a poor adaptability.

In order to solve the problem of the poor adaptability of the prior art nasal sinus stent, the present invention aims to provide a weaving method for a nasal sinus stent and a stent obtained thereof. The invention is defined by the independent claim. The dependent claims contain advantageous embodiments of the present invention.

The present invention provides a weaving method for a nasal sinus stent comprising: providing a filament; providing a weaving tool having a longitudinal central axis, wherein the weaving tool comprises a first shaping part and a second shaping part which are axially spaced from each other; wherein the first shaping part is provided with n uniformly-spaced first anchor points for hooking the filament in a first cross section perpendicular to the longitudinal central axis; the second shaping part is provided with n uniformly-spaced second anchor points for hooking the filament in a second cross section perpendicular to the longitudinal central axis; wherein n is an integer in <NUM>-<NUM>; forming an initial configuration stent by around a circumferential direction of the weaving tool, allowing a single filament starting from 1st first anchor point on the first shaping part, coming across m1 vertex intervals to extend towards the second anchor point, and then coming across m2 vertex intervals to extend towards the first anchor point, so as to complete a first "V" shaped weaving path, and then repeating the "V" shaped weaving path until the single filament returns to the 1st first anchor point, wherein the initial configuration stent has a circumference and n vertices with vertex interval obtained by dividing the circumference by n; m1 and m2 are integral multiples of <NUM>, the sum of m1+m2 is an integer, and the sum of m1+m2 is not an integral multiple of a divisor of n. The divisor of n is not equal to <NUM>. The aspect ratio of the initial configuration stent is within <NUM>-<NUM>. The nasal sinus stent is formed by a plurality of the "V" shaped weaving path, each of which comprises vertices and supporting rods symmetrically arranged at both sides of the vertices. A weaving angle of the supporting rod is within <NUM>°-<NUM>° and a vertex angle between two supporting rods is within <NUM>°-<NUM>°.

The nth first anchor point in the first anchor points is staggered or aligned with the nth second anchor point in the second anchor points on a cylindrical surface.

The nth first anchor point in the first anchor points is staggered or aligned with the nth second anchor point in the second anchor points on a lateral face of a conical frustum.

An imaginary line connecting the nth first anchor point in the first anchor points to the nth second anchor point in the second anchor points is parallel to the longitudinal central axis.

When m1=m2, n is an odd number in <NUM>-<NUM>.

An imaginary line connecting a midpoint of an imaginary line connecting the (n-<NUM>)th first anchor point in the first anchor points to the nth first anchor point to the (n-<NUM>)th second anchor point in the second anchor points is parallel to the longitudinal central axis.

The filament is monofilament or a strand forming by swirling at least two monofilaments with each other.

The weaving tool further comprises a connecting part, wherein the first shaping part is connected to the second shaping part by the connecting part to be fixed at a predetermined place.

The weaving tool further comprises a hoop around and spaced from the connecting part.

The single filament starts from the 1st first anchor point on the first shaping part, comes across m1 vertex intervals to extend towards the second anchor point between the connecting part and the hoop, comes across m2 vertex intervals to extend towards the first anchor point between the connecting part and the hoop, so as to complete a first "V" shaped weaving path, and then repeats the "V" shaped weaving path until the single filament returns to the 1st first anchor point to form the initial configuration stent.

An end-to-end connection is provided by parallel double lines formed from ends of the single filament.

The filament has intersections connected by polymer glue.

The present invention also provides a nasal sinus stent according to above method.

An outer diameter of the filament is within0. <NUM>-<NUM>, and a bending radius of the vertex is <NUM>-<NUM> times the outer diameter of the filament.

The vertex is a curved portion, a composite vertex, a negative loop vertex, a positive loop vertex, or a tridimensional vertex.

A profile of the nasal sinus stent is the same as that of the weaving tool.

The obtained nasal sinus stent according to the weaving method of the present invention has good shape adaptability, and is particularly suitable for use as a self-expanding stent in the nasal cavity. The nasal sinus stent provided by the present invention can be uniformly compressed to the first compressed configuration through the filament regular parallelogram cells. When the stent is released at the nasal cavity, the stent in the second expanding configuration can adapt to a variety of inner cavities for apposition against tissues.

In connection with appended figures, preferred embodiments of the present invention are provided and described in details.

The weaving method for a nasal sinus stent provided by the present invention comprises of providing filament <NUM> (referring to <FIG>). The filament <NUM> can be monofilament or a strand, which is formed by swirling at least two monofilaments with each other. Preferably, the at least two monofilaments have the same denier in a length direction. In one preferred embodiment, the strand is well cohesive and can't be easily separated into the monofilaments before swirling. In which, the monofilament may be the polymer filament mentioned in <CIT>, which may comprise the mentioned metallic region, flexible section and etc. In fact, the filament <NUM> may be from a degradable material, or a non-degradable material. The degradable material may be a degradable polymer material, or a degradable metal material. In which, the degradable polymer material may be selected from: polylactic acid (PLA), polyLlactic acid (PLLA or LPLA), polyglycolic acid/polylactic acid (PGLA), polycaprolactone (PCL), polyhydroxylbutyratevalerate (PHBV), polyacetylglutamicacid (PAGA), polyorthoesters (POE) and polyethylene oxide/polybutylene terephthalate (PEO/PBTP), poly-p-dioxanone (PPDO), Poly(butylene succinate) (PBS), poly(glycerol sebacate) (PGS), chitosan, PVA and copolymers or blends thereof. The degradable metal material may be selected from: magnesium metal, magnesium alloy, zinc-based alloy, iron, iron-base alloy, tungsten and tungsten-base alloy.

The weaving method for the nasal sinus stent provided by the present invention further comprises of providing a weaving tool for determining the final shape of the nasal sinus stent of the present invention. The weaving tool <NUM> has a longitudinal central axis A depicted in <FIG>, which comprises a first shaping part <NUM> and a second shaping part <NUM> which are axially spaced from each other, wherein the first shaping part <NUM> is connected to the second shaping part <NUM> by a connecting part <NUM> therebetween to be fixed at a predetermined place. The connecting part <NUM> may be a hollow structure, which is used to fix the weaving tool <NUM> properly at the predetermined place. In addition, the space between the first shaping part <NUM> and the second shaping part <NUM> can be adjusted by the axial length of the connecting part <NUM>, and thus the axial length of the nasal sinus stent is adjusted. The first shaping part <NUM> is provided with a plurality of uniformly-distributed first anchor points <NUM> for hooking the filament in a first plane (also referred to as a first cross section) perpendicular to the longitudinal central axis A. Similarly, the second shaping part <NUM> is provided with a plurality of uniformly-distributed second anchor points <NUM> for hooking the filament in a second plane (also referred to as a second cross section) perpendicular to the longitudinal central axis A. In the embodiment shown in <FIG>, the cross section profiles of the first shaping part <NUM>, connecting part <NUM> and second shaping part <NUM> are the same circular, and thus a continuous cylindrical body is formed. In this case, in addition to the first and second shaping parts <NUM>, <NUM>, a third shaping part is formed by the connecting part <NUM> for determining the final shape of the nasal sinus stent of the present invention. In addition, the cross section of the first anchor point <NUM> (or the second anchor point <NUM>) can be cylindrical, triangular, square, or semicircle, preferably cylindrical shape. Groove can be formed on the anchor point to receive and facilitate the hook of the filament. Or the anchor points can be upswept, namely the first anchor points <NUM> (or the second anchor points <NUM>) on the first shaping part <NUM> (or the second shaping part <NUM>) gradually extend away from the connecting part <NUM> to facilitate the hook of the filament and avoid the escape of the filament during the weaving and processing procedures, as shown in <FIG>.

Turning back to <FIG>, the first anchor points <NUM> comprise uniformly-spaced anchor points <NUM><NUM>, <NUM><NUM>, <NUM><NUM>, <NUM><NUM>, <NUM><NUM>. and <NUM>n. The second anchor points <NUM> comprise uniformly-spaced anchor points <NUM><NUM>, <NUM><NUM>, <NUM><NUM>, <NUM><NUM>, <NUM><NUM>. and <NUM>n. An imaginary line connecting the 1st first anchor point <NUM><NUM> to the 1st second anchor point <NUM><NUM> is parallel to the longitudinal central axis A; an imaginary line connecting the 2nd first anchor point <NUM><NUM> to the 2nd second anchor point <NUM><NUM> is parallel to the longitudinal central axis A. and an imaginary line connecting the nth first anchor point <NUM>n to the nth second anchor point <NUM>n is parallel to the longitudinal central axis A.

The weaving method provided by the present invention further comprises of weaving a single filament <NUM> on the weaving tool <NUM> to form the initial configuration stent <NUM> by manual or machine. Specifically, around a circumferential direction B (as shown in <FIG>) of the weaving tool <NUM>, the single filament <NUM> starts from anyone of the first anchor point <NUM> (or the second anchor point <NUM>) on the first shaping part <NUM> (or the shaping part <NUM>). For example, the single filament <NUM> starts from the 1st first anchor point <NUM><NUM>, comes across the connecting part <NUM> to extend toward the 3rd second anchor point <NUM><NUM>, then comes across the connecting part <NUM> to extend toward the 5th first anchor point <NUM><NUM>, so as to complete a first "V" shaped weaving path, and then repeats the "V" shaped weaving path, wherein the anchor points <NUM><NUM>, <NUM><NUM>. <NUM><NUM>, <NUM><NUM>. <NUM><NUM>, <NUM><NUM>. <NUM><NUM>, <NUM><NUM>. until the single filament returns to the 1st first anchor point <NUM><NUM>, to form the initial configuration stent <NUM>.

<FIG> shows the specific weaving path and indicates that the circumference of the stent is across for four times by one end of the filament <NUM> to meet the other end as a starting point, so as to complete a whole weaving procedure. A circle means that the circumference is across for one time in the circumferential direction B. In the present embodiment, the first circle B<NUM>, the second circle B<NUM>, the third circle B<NUM> and the forth circle B<NUM> are provided, wherein the expanded state of the first circle B<NUM> is as shown in <FIG>, the expanded state of the second circle B<NUM> is as shown in <FIG>, the expanded state of the third circle B<NUM> is as shown in <FIG>, and the expanded state of the fourth circle B<NUM> is as shown in <FIG>. After all anchor points have been across to finish the weaving procedure, an end-to-end connection is provided by a glue of polymer, a heat weld or the like, as shown in <FIG>, wherein parallel double lines are formed from ends 211to strengthen the connection of the starting point 211a and the ending point 211b, and thus to improve the stability of the shape of the stent.

Throughout the weaving procedure, the filament <NUM> can be interwoven with each other, or can be covering woven. The interweaving means that the filament <NUM> alternately, above and below, comes across the encountering preceding filament on the weaving path. The covering weaving means that the filament <NUM> only comes across the encountering preceding filament on the weaving path above. Of course, above two weaving methods can be combined, namely the interweaving and covering weaving can be combined as desired. For example, on the basis of the covering weaving, the last several "V" shaped weaving paths are interwoven. Such interwoven "V" shaped weaving path has a total circumferential distance of at least <NUM>% of the circumference. Sometimes, the distance of the entire circumference is required. The choice of the distance depends on the complexity of the overall pattern of the stent. However, regardless of the pattern of the stent, at least one "V" shaped weaving path is required to be interwoven. Preferably, ends <NUM> of the filament <NUM> are interwoven. Although the interweaving is less efficient with respect to the covering weaving, especially by manual, a relatively stable mesh can be formed through the interweaving filament, and the stent is well formed. In addition, an effect of the "pseudo-multilayer" stent can be achieved by the interweaving. In this case, a desired film (e.g., a degradable drug film) can be inserted therebetween, without the need of sewing as a covering stent.

<FIG> is a perspective view of the initial configuration stent <NUM> formed directly after the completion of the weaving step, wherein the position of the filament <NUM> corresponding to the first anchor point <NUM> (or the second anchor point <NUM>) is referred to as the first vertex <NUM> (or the second vertex <NUM>). The distance between the first vertex <NUM> and the second vertex <NUM> is the length L of the initial configuration stent <NUM>. Points of intersection of the filament <NUM> are referred to as intersections <NUM>. Legs forming the "V" shaped weaving path are referred to as supporting rods <NUM>, wherein the supporting rod <NUM> extending from the first anchor point <NUM> to the second anchor point <NUM> is referred to as a descending supporting rod, and the supporting rod <NUM> extending from the second anchor point <NUM> to the first anchor point <NUM> is referred to as an ascending supporting rod. The initial configuration stent <NUM> has a diameter D. For a stent with a circular cross-section profile, the diameter D coincides with the diameter of the cross-section circle at that location. For a stent with a non-circular cross-section profile, the diameter D is replaced by a diameter of a circle whose area is equal to the cross-section profile at that location. The length L and diameter D are two of the key factors determining the performance of the stent. The ratio of length L to diameter D is referred to as the aspect ratio L/D. The optional diameter D of the nasal sinus stent according to the present invention ranges from <NUM> to <NUM>, preferably from <NUM> to <NUM>. The optional aspect ratio ranges from <NUM> to <NUM>, preferably from <NUM> to <NUM>. Since the nasal sinus stent provided by the present invention is based on the adaptation to lesions with irregular shapes, the larger the aspect ratio L/D is, the greater the difference in the performance between the length (axial) direction and the circumferential direction becomes, the greater the anisotropy becomes, and the worse the effect of the adaptation to lesions with irregular shapes becomes. Therefore, the diameter D of the nasal sinus stent of the present invention is relatively close in size to length L. In the prior art, in order to adapt to tubular organ (such as coronary vessel) and to conform to the inner wall of the organ, the stent is usually designed to be elongated and tubular, and the minimum aspect ratio is about <NUM>, usually within <NUM>-<NUM>, and commonly within <NUM>-<NUM>.

<FIG> shows an expanded view of the initial configuration stent <NUM>, and <FIG> is a partial enlarged view of the block portion in <FIG>. The angle between the supporting rod <NUM> and the horizontal direction is referred to as weaving angle α. The angle between the two supporting rods <NUM> forming the "V" shaped weaving path is referred to vertex angle β. The weaving angle α and vertex angle β play an important role in the performance of the stent. If the vertex angle β is larger and the weaving angle α is smaller, the stent provides higher supporting force, greater rigidity, and more difficult to be compressed. Thus, the stent may be difficult to be compressed to a relative small diameter, and it is difficult to be put into a delivery device. If the vertex angle β is smaller and the weaving angle α is larger, the stent provides greater elasticity, better resilience and smaller support force. Thus, the stent may not play a good supporting role in areas where support is needed. Therefore, proper weaving angle α and vertex angle β are important parameters to ensure the performance of the stent. The weaving angle α of the weaving stent of the present invention ranges from <NUM>° to <NUM>°, and the vertex angle β ranges from <NUM>° to <NUM>°. Preferably, the weaving angle α ranges from <NUM>° to <NUM>°, and the vertex angle β ranges from <NUM>° to <NUM>°.

As shown in <FIG>, the first vertex <NUM> is a curved portion 212a formed by the filament <NUM> around the first anchor point <NUM>, which provides the stent with compression and self-expansion. Thus, the parameters of the curved portion also affect the performance of the stent. If the radius of the circle R where the curved portion is located (ie, bending radius r of the filament <NUM> at the anchor point) is too large, the stent will be difficult to be compressed. Namely, the supporting force will be too strong, and the axial ends of the stent are not easily to be compressed. If the radius is too small, the stent can't provide sufficient support. The filament <NUM> of the present invention has an outer diameter in the range of <NUM> to <NUM>, preferably in the range of <NUM> to <NUM>; and the bending radius r of the vertex <NUM> is <NUM> to <NUM> times the outer diameter of the filament <NUM>, preferably <NUM> to <NUM> times.

Since the vertices <NUM>, <NUM> directly affect the elasticity, supporting force and recovery of the stents, the curved portion 212a of the vertices of the stents can be deformed for special effects and purposes. As shown in <FIG>, the filament <NUM> comes across a composite anchor group (shown as five anchor points in the figure) to form a composite vertex 212b with a relatively large circumferential span. Such composite vertex 212b is suitable for a stent with relatively few and sparse vertices, wherein the elasticity and recovery of the vertices are strengthened by the composite vertices 212b. As shown in <FIG>, the filament <NUM> starts below the anchor point and to circle one time around the anchor point forming a negative loop vertex 212c. An intersection of the supporting rods <NUM> on both sides of the vertex of the stent is formed below the vertex, and next to the negative loop vertex. Since the instability of the stent compression is mainly due to the vertex, the intersection next to the vertex increases the stability of the stent during deformation. Such stent can be easily compressed without the aid of special compression tools. As shown in <FIG>, the filament <NUM> starts above to circle one time around the anchor point to form a positive loop vertex 212d. A spring-like stress can be provided by the positive loop vertex 212d to increase the supporting force and the recovery force after released of the stent. Although the positive loop vertex 212d does not have the intersection below the vertex, the spring formed by the loop binds the supporting rods <NUM> on both sides of the vertex to twist vertically towards the vertex, which increases the stability of the stent during deformation to some extent. It should be understood that the negative loop vertex 212c (or the positive loop vertex 212d) can also be formed by circling several times around the anchor point. As shown in <FIG>, the curved portion formed by the filament <NUM> around the anchor point can be bent backward or forward to form a tridimensional vertex 212e. An elastic ability is provided in two perpendicular directions respectively by the vertex 212e. Therefore, such stent has better supporting force and recovery than the stent with normal curved portion.

The number of vertices of the initial configuration stent <NUM> is the same as the number of anchor point. Namely, the initial configuration stent <NUM> has vertex number n; the initial configuration <NUM> has circumference C; the vertices <NUM>, <NUM> divide the circumference C into n equal parts, and the interval between the adjacent first vertices <NUM> (or the adjacent second vertices <NUM>) is referred to as vertex interval C/n; the circumferential span of the supporting rods <NUM> is a multiple of the vertex interval C/n, which is referred to as supporting rod spanning vertex interval number m (the descending supporting rod spanning vertex interval number is m1, and the ascending supporting rod spanning vertex interval number is m2), and the circumferential span of each "V" shaped weaving path is denoted in "V" shaped weaving path spanning vertex interval number m1+m2. In the present embodiment, the vertex number n is <NUM>; the supporting rod spanning vertex interval numbers m1, m2 are both equal to <NUM>, and the"V" shaped weaving path spanning vertex interval number m1+m2 is <NUM>; namely, the filament <NUM> starts from the first anchor point, comes across <NUM> vertex intervals to extend towards the second anchor point, then comes across <NUM> vertex intervals to extend towards the first anchor point, so as to complete a "V" shaped weaving path. In fact, the vertex number n according to the nasal sinus stent in the present embodiment can only be an odd number. If the vertex number n is an even number, some of the anchor points will be left and the weaving of the stent can't be completed. Moreover, the vertex number n can't be divisible by the "V" shaped weaving path spanning vertex interval number m1+m2. Otherwise the weaving of the stent can't be completed either. What's more, if the "V" shaped weaving path spanning vertex interval number m1+m2 is a divisor of vertex number n or an integral multiple of the divisor, some of the anchor points will be left and the weaving of the stent can't be completed either.

The weaving method provided by the present invention further comprises of connecting the intersections <NUM> by polymer glue. The polymer glue can be commercially available implantable glue, or can be formulated into a polymer solution by a polymer and a solvent. After the solvent at the intersection is volatilized, the polymer glue is cured. The cured intersections have elasticity, can withstand tensile deformation and are not easily cracked. Thus, the shape of the stent is fixed, and a large deformation capacity at the intersection of the supporting rod is provided. Whether the stent is formed by interweaving or covering weaving, the intersections <NUM> can be fixed by means of a joint. Specifically, the position of the intersections <NUM> connected by the joint can be adjusted as desired. <FIG> shows the intersections closest to the vertices on both ends of the stent are connected by joints; <FIG> shows the intersections at the same cross section in the middle of the stent are connected by joints; <FIG> shows all the intersections are connected by joints; <FIG> shows the non-adjacent intersections are connected by joints; <FIG> shows the intersections along one circumference span of the weaving path are connected by joints.

The weaving method provided by the present invention further comprises of heat-setting the initial configuration stent to form a final configuration stent. Preferably, the initial configuration stent is heat-set under tension, for example, at <NUM> degrees for <NUM> minutes. The heating temperature may be the temperature between the glass transition temperature and melting temperature of the filament.

The weaving method provided by the present invention further comprises of forming a drug eluting layer, which may be performed before the weaving step or after the weaving step. For example, a composite filament with sheath-core structure is first formed by coating the filament, and then the composite filament is woven by the weaving tool. For another example, the final configuration stent is first formed by heat-setting, and then the drug eluting layer is loaded on the stent by dipping, spraying, brushing, or the like. The optional drug may be the drug mentioned in <CIT>.

The same technical features as those in the embodiment <NUM> will not be described herein, and only the different steps will be described below.

As shown in <FIG>, the number of vertices of the initial configuration stent is vertex number <NUM>, and the vertices divide the circumference into <NUM> equal parts; the circumference of the initial configuration stent is C, and the interval between the adjacent first vertices is vertex interval C/<NUM>; wherein the descending supporting rod spanning vertex interval number is <NUM>; the ascending supporting rod spanning vertex interval number is <NUM>, and the circumferential span of each "V" shaped weaving path is denoted in "V" shaped weaving path spanning vertex interval number <NUM>.

Specifically, the filament starts from the 1st first anchor point, comes across <NUM> vertex intervals to extend towards the second anchor point, then comes across <NUM> vertex intervals to extend towards the first anchor point, so as to complete a "V" shaped weaving path, and then repeats the "V" shaped weaving path until the filament returns to the 1st first anchor point to form the initial configuration stent.

In fact, the vertex number n according to the nasal sinus stent in the present embodiment may be an odd number or an even number. However, the vertex number n according to the nasal sinus stent in the present embodiment can't be divisible by the "V" shaped weaving path spanning vertex interval number m1+m2. Otherwise the weaving of the stent can't be completed. What's more, if the "V" shaped weaving path spanning vertex interval number m1+m2 is a divisor of vertex number n or an integral multiple of the divisor, some of the anchor points will be left and the weaving of the stent can't be completed. For example, when n=<NUM>, m1+m2 can't be an integral multiple of the <NUM> or <NUM>, namely, m1+m2 can't be <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, etc..

The weaving tool <NUM>' comprises a first shaping part <NUM>' and a second shaping part <NUM>' which are axially spaced from each other. The first shaping part <NUM>' is provided with a plurality of first anchor points <NUM>' for hooking the filament uniformly-distributed in a first cross section. The second shaping part <NUM>' is provided with a plurality of second anchor points <NUM>' for hooking the filament uniformly-distributed in a second cross section. The first anchor points <NUM>' comprises uniformly-spaced anchor point <NUM><NUM>', anchor point <NUM><NUM>', anchor point <NUM><NUM>', anchor point <NUM><NUM>', anchor point <NUM><NUM>'. and anchor point <NUM>n'. The second anchor points <NUM>' comprises uniformly-spaced anchor point <NUM><NUM>', anchor point <NUM><NUM>', anchor point <NUM><NUM>', anchor point <NUM><NUM>', anchor point <NUM><NUM>'. and anchor point <NUM>n'. An imaginary line connecting a midpoint of an imaginary line connecting the 1st first anchor point <NUM><NUM>' to the 2cd first anchor point <NUM><NUM>' to the 1st second anchor point <NUM><NUM>' is parallel to the longitudinal central axis A. an imaginary line connecting a midpoint of an imaginary line connecting the (n-<NUM>)th first anchor point <NUM>n-<NUM>' to the nth first anchor point <NUM>n' to the (n-<NUM>)th second anchor point <NUM>n-<NUM>' is parallel to the longitudinal central axis A; an imaginary line connecting a midpoint of an imaginary line connecting the nth first anchor point <NUM>n' to the 1st first anchor point <NUM><NUM>' to the nth second anchor point <NUM>n' is parallel to the longitudinal central axis A.

As shown in <FIG>, the number of vertices of the initial configuration stent is vertex number <NUM>, and the vertices divide the circumference into <NUM> equal parts; the circumference of the initial configuration stent is C, and the interval between the adjacent first vertices is vertex interval C/<NUM> (is referred to as) ; wherein the descending supporting rod spanning vertex interval number is <NUM>; the ascending supporting rod spanning vertex interval number is <NUM>, and the circumferential span of each "V" shaped weaving path is denoted in "V" shaped weaving path spanning vertex interval number <NUM>.

In fact, the vertex number n according to the nasal sinus stent in the present embodiment may be an odd number or an even number. However, the vertex number n according to the nasal sinus stent in the present embodiment can't be divisible by the "V" shaped weaving path spanning vertex interval number m1+m2. Otherwise the weaving of the stent can't be completed. What's more, if the "V" shaped weaving path spanning vertex interval number m1+m2 is a divisor of vertex number n or an integral multiple of the divisor, some of the anchor points will be left and the weaving of the stent can't be completed.

As shown in <FIG>, the number of vertices of the initial configuration stent is vertex number <NUM>, and the vertices divide the circumference into <NUM> equal parts; the circumference of the initial configuration stent is C, and the interval between the adjacent first vertices is vertex interval C/<NUM>; wherein the ascending supporting rod spanning vertex interval number is <NUM>; the descending supporting rod spanning vertex interval number is <NUM>, and the circumferential span of each "V" shaped weaving path is denoted in "V" shaped weaving path spanning vertex interval number <NUM>.

As shown in <FIG>, the number of vertices of the initial configuration stent is vertex number <NUM> , and the vertices divide the circumference into <NUM> equal parts; the circumference of the initial configuration stent is C, and the interval between the adjacent first vertices is vertex interval C/<NUM>; wherein the descending supporting rod spanning vertex interval number is <NUM>; the ascending supporting rod spanning vertex interval number is <NUM> , and the circumferential span of each "V" shaped weaving path is denoted in "V" shaped weaving path spanning vertex interval number <NUM>.

As shown in <FIG>, the number of vertices of the initial configuration stent is vertex number <NUM> , and the vertices divide the circumference into <NUM> equal parts; the circumference of the initial configuration stent is C, and the interval between the adjacent first vertices is vertex interval C/<NUM>; wherein the descending supporting rod spanning vertex interval number is <NUM>; the ascending supporting rod spanning vertex interval number is <NUM>, and the circumferential span of each "V" shaped weaving path is denoted in "V" shaped weaving path spanning vertex interval number <NUM>.

Specifically, the filament starts from the 1st first anchor point, comes across <NUM> vertex interval to extend towards the second anchor point, then comes across <NUM> vertex intervals to extend towards the first anchor point, so as to complete a "V" shaped weaving path, and then repeats the "V" shaped weaving path until the filament returns to the 1st first anchor point to form the initial configuration stent. In fact, the vertex number n according to the nasal sinus stent in the present embodiment may be an odd number or an even number. However, the vertex number n according to the nasal sinus stent in the present embodiment can't be divisible by the "V" shaped weaving path spanning vertex interval number m1+m2. Otherwise the weaving of the stent can't be completed. What's more, if the "V" shaped weaving path spanning vertex interval number m1+m2 is a divisor of vertex number n or an integral multiple of the divisor, some of the anchor points will be left and the weaving of the stent can't be completed.

As shown in <FIG>, the number of vertices of the initial configuration stent is vertex number <NUM>, and the vertices divide the circumference into <NUM> equal parts; the circumference of the initial configuration stent is C, and the interval between the adjacent first vertices is vertex interval C/<NUM>; wherein the descending supporting rod spanning vertex interval number is <NUM>; the ascending supporting rod spanning vertex interval number is <NUM> , and the circumferential span of each "V" shaped weaving path is denoted in "V" shaped weaving path spanning vertex interval number <NUM>.

Specifically, the filament starts from the 1st first anchor point, comes across <NUM> vertex intervals to extend towards the second anchor point, then comes across <NUM> vertex intervals to extend towards the first anchor point, so as to complete a "V" shaped weaving path, and then repeats the "V" shaped weaving path until the filament returns to the 1st first anchor point to form the initial configuration stent.

The profile of the weaving tool coincides with that of the initial configuration stent as those in the embodiment <NUM>. However, the profile of the weaving tool is not a cylindrical body, and the profile of the corresponding initial configuration stent is not a cylindrical body as shown in <FIG>. The profile of the initial configuration stent will be described below, and the description of the corresponding weaving tool is omitted here.

As shown in <FIG>, the initial configuration stent 2a is big at both ends but small in the middle. Namely, the diameters of the ends <NUM> of the initial configuration stent 2a are larger than the diameter of the middle <NUM>. In the present embodiment, the diameter of the initial configuration stent 2a increases gradually from the middle <NUM> towards the ends <NUM>. The formed stent is also referred to as a flared stent, wherein the two ends can be formed as positioning portion to relatively fix the stent to the lesion.

The first shaping part and the second shaping part of the weaving tool have the same cross sectional profile and are circular as those in the embodiment <NUM>. However, the cross sectional profile of the connecting part is smaller than that of the first shaping part (or the second shaping part). In addition, the weaving tool of the present embodiment further comprises a hoop around and spaced from the connecting part. Specifically, the filament starts from the 1st first anchor point, comes across m1 vertex intervals to extend towards the second anchor point between the hoop and the connecting part, then comes across m2 vertex intervals to extend towards the first anchor point between the hoop and the connecting part, so as to complete a first "V" shaped weaving path, and then repeats the "V" shaped weaving path until the filament returns to the 1st first anchor point to form the initial configuration stent 2b.

As shown in <FIG>, the initial configuration stent 2b is big at both ends but small in the middle. Namely, the diameters of the ends <NUM>' of the initial configuration stent 2b are larger than the diameter of the middle <NUM>'. In the present embodiment, the diameter of the initial configuration stent 2b increases gradually from the middle <NUM>' towards the ends <NUM>'. The formed stent is also referred to as a flared stent, wherein the two ends can be formed as positioning portion to relatively fix the stent to the lesion.

As shown in <FIG>, the initial configuration stent 2c is small at both ends but big in the middle. Namely, the diameters of the ends <NUM>" of the initial configuration stent 2c are smaller than the diameter of the middle <NUM>". In the present embodiment, the diameter of the initial configuration stent 2c decreases gradually from the middle <NUM>" towards the ends <NUM>". The formed stent is also referred to as convergent stent, tending to be an elliptical-shaped, egg-shaped, or even spherical-shaped stent, which can be placed in a cavity closing to a circular space.

As shown in <FIG>, the initial configuration stent 2d is conical frustum shaped. Namely, the diameter of the first end 216a‴ of the initial configuration stent 2d is smaller than the diameter of the second end 216b"'. In the present embodiment, the diameter of the initial configuration stent 2d increases gradually from the first end 216a‴ towards the second end 216b". The formed stent has a slow transition of the supporting force along the axial direction, which does not have a poor radical force at ends of the convergent stent.

The weaving tool in the present embodiment is conical frustum shaped. It is known that the conical frustum is a geometry formed by the rotation of a right trapezoid, wherein the leg perpendicular to the base defines the rotation axis, and the geometry is enclosed by the surfaces formed by the other leg and bases. The rotation axis is referred to as the axis of the conical frustum. The round surfaces formed by the rotation of the top and bottom bases are referred to as the top and bottom faces of the conical frustum. The curved surface formed by the rotation of the other leg is referred to as lateral face the conical frustum. The leg of the right trapezoid on the lateral face is referred to as the generatrix of the conical frustum. In the present embodiment, the axis of the conical frustum is the longitudinal central axis A of the weaving tool; the imaginary line connecting the nth first anchor point (<NUM>n) in the first anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) to the nth second anchor point (<NUM>n) in the second anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) is the generatrix of the conical frustum, thus the first vertices and the second vertices are aligned on the lateral face of the conical frustum.

In another embodiment, the imaginary line connecting the midpoint of the imaginary line connecting the (n-<NUM>)th first anchor point (<NUM>n-<NUM>) to the nth first anchor point (<NUM>n) in the first anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) to and the (n-<NUM>)th second anchor point (<NUM>n-<NUM>) in the second anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) is the generatrix of the conical frustum, thus the first vertices and the second vertices alternate on the lateral face of the conical frustum.

When stents as shown in <FIG> are in complete longitudinal symmetry, the first anchor points and the second anchor points are distributed on the same cylindrical surface. The first vertices and the second vertices can be aligned as embodiment <NUM>, namely the imaginary line connecting the nth first anchor point (<NUM>n) in the first anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) to the nth second anchor point (<NUM>n) in the second anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) is parallel to the longitudinal central axis A. Also, the first vertices and the second vertices can alternate as embodiment <NUM>, namely the imaginary line connecting the midpoint of the imaginary line connecting the (n-<NUM>)th first anchor point (<NUM>n-<NUM>) to the nth first anchor point (<NUM>n) in the first anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) to and the (n-<NUM>)th second anchor point (<NUM>n-<NUM>) in the second anchor points (<NUM><NUM>, <NUM><NUM>. <NUM>n) is parallel to the longitudinal central axis A.

Claim 1:
A weaving method for a nasal sinus stent comprising:
providing a filament (<NUM>);
providing a weaving tool (<NUM>) having a longitudinal central axis (A),
wherein the weaving tool comprises a first shaping part (<NUM>) and a second shaping part (<NUM>) which are axially spaced from each other;
wherein the first shaping part (<NUM>) is provided with n uniformly-spaced first anchor points (<NUM> , <NUM> ......111n) for hooking the filament in a first cross section perpendicular to the longitudinal central axis (A); the second shaping part (<NUM>) is provided with n uniformly-spaced second anchor points (<NUM> , <NUM> ......121n) for hooking the filament in a second cross section perpendicular to the longitudinal central axis (A); wherein n is an integer in <NUM>-<NUM>;
forming an initial configuration stent (<NUM>) by around a circumferential direction (B) of the weaving tool (<NUM>), allowing a single filament (<NUM>) starting from 1st first anchor point (<NUM>) on the first shaping part (<NUM>), coming across m1 vertex intervals to extend towards the second anchor point, and then coming across m2 vertex intervals to extend towards the first anchor point, so as to complete a first "V" shaped weaving path, and then repeating the "V" shaped weaving path until the single filament returns to the 1st first anchor point (<NUM>),
wherein the initial configuration stent has a circumference (C) and n vertices with vertex interval obtained by dividing the circumference (C) by n; m1 and m2 are integral multiples of <NUM>, the sum of m1+m2 is an integer, and the sum of m1+m2 is not an integral multiple of a divisor of n,
wherein the divisor of n is not equal to <NUM>,
wherein the aspect ratio of the initial configuration stent (<NUM>) is within <NUM>- <NUM>,
wherein the nasal sinus stent (<NUM>) is formed by a plurality of the "V" shaped weaving path, each of which comprises vertices (<NUM>, <NUM>) and supporting rods (<NUM>) symmetrically arranged at both sides of the vertices (<NUM>, <NUM>),
wherein a weaving angle (a) of the supporting rod (<NUM>) is within <NUM>°-<NUM>°, wherein a vertex angle (β) between two supporting rods (<NUM>) is within <NUM>°-<NUM>°.