Hybrid stent

Abstract

A hybrid stent includes multiple main cells aligned in a spiral shape and including multiple first link units which are aligned diagonally and spaced at a predetermined distance from each other and multiple second link units which connect adjacent first link units among the multiple first link units and are spaced at a predetermined distance from each other, and one or more open cells adjacent to the multiple main cells in a longitudinal direction and aligned in a spiral shape.

Claims

1. A hybrid stent having a cylindrical structure of which both ends are opened in a longitudinal direction, the hybrid stent comprising: multiple series of main closed cells in which each series of main closed cells are consecutively aligned in a spiral shape along a longitudinal direction of the hybrid stent and slantly aligned at an angle of 45 degrees or less with respect to the longitudinal direction; multiple first link units which are aligned slantly with respect to the longitudinal direction and spaced at a predetermined distance from each other, and multiple pairs of second link units in which each pair of second link units is aligned along and between two neighboring series of main closed cells and connects two neighboring first link units, wherein each main closed cell is defined by two neighboring first link units and two neighboring second link units; and multiple series of elongate open cells in which each series of open cells are aligned end-to-end in a spiral shape along and between two neighboring series of main closed cells in the longitudinal direction, wherein each open cell is defined by each pair of second link units and two neighboring first link units, and each open cell is defined to correspond to two or more neighboring main closed cells.

2. The hybrid stent of claim 1, wherein the multiple series of open cells and the multiple series of main closed cells are aligned sequentially in an alternate manner.

3. The hybrid stent of claim 1, wherein the each open cell has a width smaller than that of the each main closed cell.

4. The hybrid stent of claim 1, wherein the multiple first link units are formed to have a wave curve, or the multiple second link units are formed to have a wave curve.

5. The hybrid stent of claim 4, wherein the wave curve has an S-shape.

6. The hybrid stent of claim 1, wherein the multiple second link units are formed in a linear shape.

7. The hybrid stent of claim 1, wherein the each main closed cell has a tilted diamond shape.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a diagram illustrating a forward hybrid stent according to an exemplary embodiment of the present disclosure;

(2) FIG. 2 is a diagram illustrating a backward hybrid stent according to an exemplary embodiment of the present disclosure;

(3) FIG. 3A is a diagram illustrating a conventional stent including closed main cells only; and

(4) FIG. 3B to FIG. 3E are diagrams illustrating various stents according to an exemplary embodiment of the present disclosure.

(5) FIG. 4 show a test method of radial force for hybrid stents according to the present disclosure.

(6) FIG. 5 show a test method of flexibility for hybrid stents according to the present disclosure.

BEST MODE FOR CARRYING OUT THE INVENTION

(7) Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that the present disclosure may be readily implemented by those skilled in the art. However, it is to be noted that the present disclosure is not limited to the embodiments but can be embodied in various other ways. In drawings, parts irrelevant to the description are omitted for the simplicity of explanation, and like reference numerals denote like parts through the whole document.

(8) Through the whole document, the term connected to or coupled to that is used to designate a connection or coupling of one element to another element includes both a case that an element is directly connected or coupled to another element and a case that an element is electronically connected or coupled to another element via still another element.

(9) Through the whole document, the term on that is used to designate a position of one element with respect to another element includes both a case that the one element is adjacent to the another element and a case that any other element exists between these two elements.

(10) Further, through the whole document, the term comprises or includes and/or comprising or including used in the document means that one or more other components, steps, operation and/or existence or addition of elements are not excluded in addition to the described components, steps, operation and/or elements unless context dictates otherwise.

(11) Hereinafter, the present disclosure will be explained in detail with reference to the accompanying drawings.

(12) A stent of the present disclosure can be applied to, for example, a cerebrovascular stent used for cerebrovascular disease or a coronary artery stent used for cardiovascular stenosis such as a heart attack or myocardial infarction. However, the stent of the present disclosure is not limited thereto and can be applied to various application fields.

(13) FIG. 1 is a diagram illustrating a forward hybrid stent according to an exemplary embodiment of the present disclosure, and FIG. 2 is a diagram illustrating a backward hybrid stent according to an exemplary embodiment of the present disclosure.

(14) According to an exemplary embodiment of the present disclosure, a hybrid stent 1 may have a cylindrical structure of which both ends are opened in a longitudinal direction. Further, in the hybrid stent 1, multiple main cells 10 and multiple open cells 20 may be aligned in an alternate manner.

(15) The hybrid stent 1 can be classified as the forward hybrid stent 1 or the backward hybrid stent 1 depending on an alignment position of the open cell 20.

(16) Furthermore, in the hybrid stent 1, the main cells 10 may be aligned in a spiral shape the open cells 20 configured to increase flexibility may be aligned between the main cells 10 aligned in the spiral shape. In this case, each open cell may be aligned corresponding to at least two main cells 10. As the number of main cells 10 corresponding to one open cell 20 is increased, the flexibility of the stent can be improved. In this case, the flexibility of the hybrid stent 1 can be adjusted by adjusting the number of main cells.

(17) Also, the open cells 20 of the hybrid stent 1 may be aligned in the same manner as the main cells 10 aligned in a spiral direction.

(18) Hereinafter, a structure of the hybrid stent 1 will be described in detail.

(19) In the hybrid stent 1, the multiple main cells 10 and the multiple open cells 20 are aligned in a spiral shape. Thus, the hybrid stent 1 can have excellent flexibility and expansion force required for a stent.

(20) The multiple main cells 10 may include multiple first link unit 11 which are aligned diagonally and spaced at a predetermined distance from each other. When the hybrid stent 1 is expanded, the multiple first link units 11 may be curved into a wave curve along a longitudinal direction of the hybrid stent 1. That is, the first link units 11 may be formed including peaks and valleys alternating each other.

(21) Meanwhile, the multiple main cells 10 may include multiple second link unit 12 which connect adjacent first link units 11 among the multiple first link units 11 and are spaced at a predetermined distance from each other.

(22) The multiple main cells 10 may be aligned slantly with respect to the longitudinal direction of the hybrid stent 1 as illustrated in FIG. 1 and FIG. 2. For example, the main cell 10 may be slantly formed at an angle of 30 to 60 with respect to the longitudinal direction of the hybrid stent 1.

(23) Meanwhile, one of the multiple main cells 10 may be formed by two first link units 11 facing each other among the multiple first link units 11 and two second link units 12 facing each other among the multiple second link units 12. In this regard, one main cell 10 may have a tilted diamond shape.

(24) Meanwhile, since the first link unit 11 and the second link unit 12 are connected adjacent to each other, one main cell 10 may have four vertices in approximately up and down directions and left and right directions, respectively. A line (not illustrated) connecting vertices a and b in the left and right directions among the four vertices may be at an angle of 45 or less to the longitudinal direction of the hybrid stent 1. That is, desirably, the line connecting the vertices a and b of the main cell 10 may be positioned in a recapture direction and thus can be recaptured.

(25) Further, at least one of the first link units 11 and the second link units 12 forming the one main cell 10 may be formed into a wave curve. In this case, the wave curve may have an S-shape. For example, referring to FIG. 1, the first link unit 11 may be formed into a wave curve and the second link unit 12 may be formed into a linear shape.

(26) For example, the multiple open cells 20 may be aligned sequentially in an alternate manner in a spiral shape along the longitudinal direction of the multiple main cells 10 and the hybrid stent 1. In this case, one open cell 20 may correspond to the multiple main cells 10. That is, the main cell can be understood as a closed cell and the open cell 10 can be understood as a cell having an area corresponding to multiple closed cells aligned side by side. The concepts of the closed cell and the open cell are obvious to those skilled in the art. Therefore, a more detailed explanation thereof will be omitted. Multiple series of elongate open cells 20 are aligned end-to-end in a spiral shape along and between two neighboring series of main closed cells 10.

(27) As illustrated in FIG. 1 and FIG. 2, the open cell 20 may be formed to have a greater length and a smaller width than the main cell 10. Herein, referring to FIG. 1, the length of the open cell 20 may refer to a length in a progress direction of the spiral (11 to 5 o'clock directions in FIG. 1) and the width of the open cell 20 may refer to a width of the spiral.

(28) In addition, a cavity of the open cell 20 may be formed smaller than a cavity of the main cell 10. Since the open cell 20 has a smaller cavity than the main cell 10, a higher flexibility than that of a conventional closed type (see the basic type in FIG. 3A) can be secured in the range in which a cerebrovascular stent can be recaptured.

(29) Herein, as illustrated in FIG. 1 and FIG. 2, one of the multiple open cells 20 may be aligned adjacent to two or more main cells 10. Although FIG. 1 and FIG. 2 illustrate that one open cell 20 is aligned adjacent to two main cells 10, the number of main cells 10 is not limited.

(30) Meanwhile, if the multiple open cells 20 are aligned at positions adjacent to the main cells 10, they may be aligned at various positions. That is, the open cell 20 may be aligned at a position adjacent to the second link unit 12 of the main cell 10 as illustrated in FIG. 1.

(31) More specifically, the multiple open cells 20 may be aligned adjacent to the second link unit 12 formed into a linear shape as described above. The hybrid stent 1 configured as described above can be improved in a recapture function.

(32) In another exemplary embodiment, the open cell 20 may be aligned at a position adjacent to the first link unit 11 of the main cell 10 as illustrated in FIG. 2.

(33) More specifically, the multiple open cells 20 may be aligned adjacent to the first link unit formed into a wave curve as described above. The hybrid stent configured as described above can be improved in flexibility.

(34) Hereinafter, various stents according to an exemplary embodiment of the present disclosure will be described by comparison with a conventional stent.

(35) FIG. 3A is a diagram illustrating a conventional stent including closed main cells only, and FIG. 3B to FIG. 3E are diagrams illustrating various stents according to an exemplary embodiment of the present disclosure.

(36) The stent s illustrated in FIG. 3A is a conventional stent including the main cells 10 only. The stent s illustrated in FIG. 3A includes the closed main cells 10 only and thus has a remarkably lower flexibility than the hybrid stent 1 according to an exemplary embodiment of the present disclosure. In the following description, the stent illustrated in FIG. 3A is defined as a basic stent.

(37) FIG. 3B is a diagram illustrating the hybrid stent 1 according to an exemplary embodiment of the present disclosure in which one open cell 20 is aligned corresponding to two main cells 10. Further, in the hybrid stent 1 illustrated in FIG. 3B, the open cell 20 may be aligned adjacent to the second link unit 12 of the main cell 10, i.e., in the neighborhood of the second link unit 12. In the following description, the hybrid stent 1 illustrated in FIG. 3B will be defined as a first forward stent.

(38) FIG. 3C is a diagram illustrating the stent 1 according to an exemplary embodiment of the present disclosure in which one open cell 20 is aligned corresponding to three main cells 10. Further, in the hybrid stent 1 illustrated in FIG. 3C, the open cell 20 may be aligned adjacent to the second link unit 12 of the main cell 10, i.e., in the neighborhood of the second link unit 12, like the hybrid stent 1 illustrated in FIG. 3B. In the following description, the hybrid stent 1 illustrated in FIG. 3C will be defined as a second forward stent.

(39) FIG. 3D is a diagram illustrating the hybrid stent 1 according to an exemplary embodiment of the present disclosure in which one open cell 20 is aligned corresponding to three main cells 10 and the open cell 20 may be aligned adjacent to the first link unit 11 of the main cell 10, i.e., in the neighborhood of the first link unit 11. In the following description, the hybrid stent 1 illustrated in FIG. 3D will be defined as a backward stent.

(40) FIG. 3E is a diagram illustrating the hybrid stent 1 according to an exemplary embodiment of the present disclosure in which one open cell 20 is aligned corresponding to three main cells 10 and which is similar to the stent illustrated in FIG. 3D. However, in the stent illustrated in FIG. 3D, multiple open cells 20 are continuously formed into a spiral shape and multiple main cells 10 are formed into a spiral shape as being adjacent to the multiple open cells 20, whereas in the stent illustrated in FIG. 3E, one open cell 20 forms a part of a spiral shape and three main cells 10 form a part of the spiral shape as being adjacent to the one open cell 20. Thus, the stent illustrated in FIG. 3D and the stent illustrated in FIG. 3E are different in shape. In other words, in an exemplary embodiment of the stent illustrated in FIG. 3E, it can be seen that each open cell 20 is discontinuously formed as deviating from an open cell 20 adjacent thereto in a longitudinal direction of the stent and main cells 20 corresponding in number to the one open cell 20 (three in FIG. 3E) are continuously formed into a spiral shape.

(41) Also, the hybrid stent 1 according to an exemplary embodiment of the present disclosure may be formed as a hybrid structure including a forward stent and a backward stent.

(42) Meanwhile, Table 1 shows the result of performance comparison among the basic stent, the first forward stent, the second forward stent, and the backward stent.

(43) TABLE-US-00001 TABLE 1 Radial force Flexibility Testing FIG. 4 FIG. 5 method Basic type 1.380N 0.250N First 1.010N 0.186N forward type Second 0.728N 0.152N forward type Backward 0.966N 0.174N type

(44) As shown in Table 1, the first forward, second forward, and backward hybrid stents according to an exemplary embodiment of the present disclosure may be reduced in radial force and improved in flexibility as compared with the conventional basic stent.

(45) Meanwhile, the hybrid stent 1 according to an exemplary embodiment of the present disclosure can be understood from the following point of view.

(46) The hybrid stent 1 according to an exemplary embodiment of the present disclosure can be understood as including an open cell unit including one or more open cells 20 and a main cell unit including multiple main cells 10 in which the open cell unit and the main cell unit are aligned in an alternate manner along a spiral direction and thus provide the cylindrical structure.

(47) For example, referring to an exemplary embodiment illustrated in FIG. 3D, the stent 1 illustrated in FIG. 3D may include an open cell unit including one open cell 20 and a main cell unit including three main cells 10 which are aligned in an alternate manner along a spiral direction.

(48) Specifically, according to the above-described point of view, it has been described that in the stent 1 illustrated in FIG. 3D, multiple open cells 20 are formed into a spiral shape including only the open cells 20 along the 2 to 8 o'clock directions and multiple main cells 10 are formed into a spiral shape including only the main cells 10 along the 2 to 8 o'clock directions as being adjacent to the spiral shape of the multiple open cells 20 and the longitudinal direction of the stent. However, according to the present point of view, it can also be understood that the stent 1 illustrated in FIG. 3D has a spiral shape formed by aligning one open cell 20 (open cell unit) and three main cells 10 (main cell unit) in an alternate manner along the 11 to 5 o'clock directions.

(49) That is, according to the above-described point of view, it can be understood that the hybrid stent 1 according to an exemplary embodiment of the present disclosure has a cylindrical structure formed by combining two spiral shapes (a spiral formed by main cells and a spiral formed by open cells), whereas according to the present point of view, it can be understood that the hybrid stent 1 according to an exemplary embodiment of the present disclosure has a cylindrical structure formed by only one spiral shape in which open cells and main cells are combined.

(50) Further, it can also be understood that in the stent 1 according to an exemplary embodiment illustrated in FIG. 3E, an open cell unit including one open cell 20 and a main cell unit including three main cells 10 are aligned in an alternate manner along a spiral direction.

(51) As illustrated in FIG. 3E, in the hybrid stent 1 according to an exemplary embodiment of the present disclosure, each open cell unit may be at least partially discontinuous with an open cell unit adjacent thereto along a longitudinal direction of the cylindrical structure. Specifically, as compared with the stent 1 according to the exemplary embodiment illustrated in FIG. 3D in which the open cell units are continuously connected to each other along a width direction of the spiral (2 to 8 o'clock directions in FIG. 3D), in the stent 1 illustrated in FIG. 3E, the open cell units are not continuously connected to each other along a width direction of the spiral (2 to 8 o'clock directions in FIG. 3E) but entirely (or partially) deviate from each other.

(52) The present point of view can also be understood from the stent 1 according to the exemplary embodiments illustrated in FIG. 3B and FIG. 3C. Specifically, the stent 1 illustrated in FIG. 3B may have a cylindrical structure with a spiral shape formed by aligning one open cell 20 (open cell unit) and two main cells 10 (main cell unit) in an alternate manner along the 2 to 8 o'clock directions. Also, the stent 1 illustrated in FIG. 3C may have a cylindrical structure with a spiral shape formed by aligning one open cell 20 (open cell unit) and three main cells 10 (main cell unit) in an alternate manner along the 2 to 8 o'clock directions.

(53) Further, referring to FIG. 3B to FIG. 3E, a main cell unit may include multiple main cells aligned side by side along a width direction of a spiral. Specifically, in FIG. 3B, two main cells are aligned side by side along a width direction of a spiral (11 to 5 o'clock directions) and in FIG. 3C, three main cells are aligned side by side along a width direction of a spiral (11 to 5 o'clock directions). Also, in FIG. 3D and FIG. 3E, three main cells are aligned side by side along a width direction of a spiral (2 to 8 o'clock directions).

(54) Also, an open cell unit may include one or more open cells aligned side by side along the width direction of the spiral. Although FIG. 3B to FIG. 3E illustrate that one open cell is aligned, multiple open cells may be aligned side by side along the width direction of the spiral. However, desirably, the number of open cells aligned side by side along the width direction of the spiral may be set to be smaller than the number of main cells aligned side by side along the width direction of the spiral considering the concepts of an open cell and a main cell (closed cell).

(55) As described above, the hybrid stent 1 according to an exemplary embodiment of the present disclosure has excellent flexibility and thus can be applied to a complicated and tortuous blood vessel of the brain, and also has a stent structure which can be recaptured to be adjusted in position during a treatment and thus is optimized for a blood vessel of the brain.

(56) However, as described above, application fields of the stent of the present disclosure are not limited thereto. For example, the stent of the present disclosure can be applied to a cerebrovascular stent used for cerebrovascular disease and a coronary artery stent used for cardiovascular stenosis such as a heart attack or myocardial infarction. Also, the stent of the present disclosure can be applied to various application fields and similar fields relevant to a stent in addition to the above-described cerebrovascular stent and coronary artery stent.

(57) The above description of the present disclosure is provided for the purpose of illustration, and it would be understood by those skilled in the art that various changes and modifications may be made without changing technical conception and essential features of the present disclosure. Thus, it is clear that the above-described embodiments are illustrative in all aspects and do not limit the present disclosure. For example, each component described to be of a single type can be implemented in a distributed manner. Likewise, components described to be distributed can be implemented in a combined manner.

(58) The scope of the present disclosure is defined by the following claims rather than by the detailed description of the embodiment. It shall be understood that all modifications and embodiments conceived from the meaning and scope of the claims and their equivalents are included in the scope of the present disclosure.