VASCULAR CAGES AND METHODS OF MAKING AND USING THE SAME
20190175184 ยท 2019-06-13
Inventors
- Delilah Hui (American Canyon, CA, US)
- Edsel San Diego (San Jose, CA, US)
- Ben Tompkins (Danville, CA, US)
Cpc classification
A61B2017/12054
HUMAN NECESSITIES
A61B17/12177
HUMAN NECESSITIES
A61B2090/3966
HUMAN NECESSITIES
A61B2017/00911
HUMAN NECESSITIES
A61B17/12172
HUMAN NECESSITIES
A61B17/1215
HUMAN NECESSITIES
International classification
Abstract
A vascular cage comprises a self-expandable frame including a plurality of elongated flexible bands. The frame is configured to transition between a compressed configuration and an expanded configuration. The expanded frame may form a three-dimensional cage configured to surround an interior volume as the frame is deployed. At least some of the plurality of bands may have a substantially rectangular cross-section.
Claims
1. A vascular cage comprising: a self-expandable frame including a plurality of elongated flexible bands, said frame being configured to transition between a compressed configuration and an expanded configuration, wherein the expanded frame forms a three-dimensional cage configured to surround an interior volume as the frame is deployed, and wherein at least some of the plurality of bands have a substantially rectangular cross-section.
2. An occlusive system comprising: the vascular cage of claim 1; and a cage delivery catheter configured to constrain the self-expandable frame in its compressed configuration and to release the self-expandable frame into a target location in a vasculature in its expanded configuration.
3. (canceled)
4. The vascular cage of claim 1, wherein at each of the plurality of the bands comprises a first bend when said frame is in its expanded configuration.
5-12. (canceled)
13. The vascular cage of claim 1, wherein the substantially rectangular cross-section allows at least some of the plurality of bands to be packed more closely in a cage delivery catheter when the self-expandable frame is constrained in its compressed configuration in said catheter.
14. The vascular cage of claim 1, wherein the substantially rectangular cross-section allows a higher density of bands to be packed in a cage delivery catheter with reduced empty space between adjacent bands when the self-expandable frame is constrained in its compressed configuration in said catheter.
15. The vascular cage of claim 1, wherein at least one band comprises a cross-section having varying shape, size, area, and/or longitudinal thickness profile.
16. The vascular cage of claim 15, wherein said band comprises a first end having a larger cross-sectional area than a second end.
17. The vascular cage of claim 15, wherein said band comprises a first end having a different cross-sectional shape than a second end.
18. The vascular cage of claim 15, wherein said cross-section having the varying shape, size, area, and/or longitudinal thickness profile is formed by preferential etching of said band.
19. The vascular cage of claim 1, wherein the self-expandable frame is generally spherical or ovoid in its expanded configuration.
20. The vascular cage of claim 1, wherein the self-expandable frame comprises at least one dimpled portion in its expanded configuration.
21. The vascular cage of claim 1, further comprising a wire coil wrapped around a portion of at least some of the plurality of bands.
22. The vascular cage of claim 21, wherein the wire coil comprises a substantially rectangular shaped cross-section.
23. The vascular cage of claim 22, wherein the wire coil comprises a radio opaque material.
24. The vascular cage of claim 23, wherein the radio opaque material comprises a metal selected from the group consisting of platinum and platinum alloys.
25. The vascular cage of claim 21, wherein the wire coil is configured to provide structural reinforcement to said plurality of bands.
26.-29. (canceled)
30. The vascular cage of claim 21, wherein the wire coil is not wrapped around a distal portion of said plurality of bands in order to allow bendability or flexibility of the bands at said distal portions.
31. The vascular system of claim 2, wherein the cage delivery catheter comprises a shaft having a lumen, a sidewall, at least one urging element formed in the sidewall, and a first filament disposed in the lumen.
32. The vascular system of claim 31, wherein the self-expandable frame comprises a second filament having a proximal end including a retention element which is disposed in the lumen of the shaft, said second filament further having a distal end coupled to a proximal end of the plurality of bands, wherein the retention element is releaseably retained within the lumen by the first filament which engages the retention element against the urging element in the sidewall to prevent the retention element from exiting a distal end of the shaft, wherein the first filament may be proximally retracted to release the retention member from the urging element and release the plurality of bands from the distal end of the lumen.
33. The vascular system of claim 32, wherein said retention element comprises a ball.
34. The vascular system of claim 31, wherein said sidewall comprises an aperture.
35. The vascular cage of claim 1, further comprising: a pusher wire having an attachment fixture thereon; and a severable deployment junction located at proximal ends of the plurality of bands releasably connecting each of said plurality of bands to said pusher wire.
36. The vascular cage of claim 1, wherein the three-dimensional cage provides an interior space allowing one or more embolic coils to be deployed therein or proximate thereto.
37. The vascular cage of claim 1, wherein the self-expandable frame comprises three to ten elongated flexible bands.
38. The vascular cage of claim 37, wherein the self-expandable frame preferentially comprises five to eight elongated flexible bands.
39. A method of forming an vascular cage, said method comprising: providing a tube; laser cutting the tube to form a plurality of elongated flexible bands, wherein at least some of the plurality of bands have a substantially rectangular cross-section; and forming a self-expandable frame comprising said plurality of bands, said frame being configured to transition between a compressed configuration and an expanded configuration, wherein the expanded frame forms a three-dimensional cage configured to surround an interior volume as the frame is deployed.
40. The method of claim 39, wherein tube is formed from a monolithic block of material having super-elastic and shape memory material properties.
41. The method of claim 40, wherein the tube comprises an elongated nitinol tube.
42. The method of claim 39, wherein the tube is laser cut such that the bands remain connected at an uncut first end of the tube.
43. The method of claim 42, wherein distal ends of the bands are cut free from each other, and wherein the distal ends of said bands are located at a second end of the tube opposite to the uncut first end of the tube.
44. The method of claim 43, wherein the self-expandable frame is formed by connecting the distal ends of said bands using an attachment material.
45. The method of claim 42, wherein the tube is laser cut such that the bands remain connected at an uncut second end of the tube opposite to the first end of the tube.
46. The method of claim 39, wherein the tube is laser cut such that the bands are fully separated from each other.
47. The method of claim 46, wherein the self-expandable frame is formed by connecting first ends of said bands to each other at a first location and connecting second ends of said bands to each other at a second location.
48. The method of claim 39, further comprising: inserting a wire coil over an open end of at least some of the plurality of bands; and wrapping the wire coil around a portion of said bands.
49. The method of claim 48, wherein the wire coil comprises a substantially rectangular shaped cross-section.
50. The method of claim 48, wherein the wire coil comprises a radio opaque material.
51. The method of claim 50, wherein the radio opaque material comprises a metal selected from the group consisting of platinum and platinum alloys.
52. The method of claim 39, further comprising the step of forming a self expandable frame further comprises placing the frame over a shape setting fixture to form an assembly, and processing the assembly to confer a set shape on the frame.
53. A method of forming an vascular cage, said method comprising: providing a plurality of bands comprising one or more shape memory materials; forming a self-expandable frame comprising said plurality of bands, said frame being configured to transition between a compressed configuration and an expanded configuration, wherein the expanded frame forms a three-dimensional cage configured to surround an interior volume as the frame is deployed.
54. A method of occluding a vascular location, said method comprising: providing the vascular cage of claim 1; delivering the vascular cage while constrained in its compressed configuration to a target site in the vasculature; releasing the vascular cage from constraint so that it expands to its expanded configuration at the target location.
55. The method of claim 54, wherein delivering comprises: positioning a distal end of a cage delivery catheter at a target location in a patient's vasculature; advancing the vascular cage in its compressed configuration through a lumen of the cage delivery catheter.
56. The method of claim 54, wherein releasing comprises releasing the vascular cage from the distal end of the cage delivery catheter so that the vascular cage self-expands at the target location.
57. The method of claim 54, wherein the target location is an aneurysm.
58. The method of claim 54, wherein the target location is a blood vessel lumen.
59. The method of claim 54, further comprising delivering coils into the interior volume of the vascular cage or proximate to the vascular cage after the vascular cage has been released.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
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DETAILED DESCRIPTION OF THE INVENTION
[0057] While preferred embodiments of the present invention have been shown and described herein, it will be appreciated by those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that methods and structures within the scope of these claims and their equivalents be covered thereby.
[0058] It should be noted that the accompanying figures are intended to illustrate the general characteristics of methods and materials with reference to certain example embodiments of the invention and thereby supplement the detailed written description provided below. These drawings are not, however, to scale and may not precisely reflect the characteristics of any given embodiment, and should not be interpreted as defining or limiting the range of values or properties of embodiments within the scope of this invention. In particular, the relative sizing and positioning of particular elements and structures may be reduced or exaggerated for clarity. The use of similar or identical reference numbers in the various drawings is intended to indicate the presence of a similar or identical element or feature.
[0059] The invention provides a vascular cage comprising a self-expandable frame. The frame may include a plurality of elongated flexible bands. The frame is configured to transition between a compressed configuration, usually being externally constrained in a delivery catheter or sheath, and an expanded configuration. The expanded frame may form a three-dimensional cage configured to occupy and/or surround an interior volume within a vascular aneurysm, blood vessel lumen, or the like, as the frame is deployed. At least some of the plurality of bands may have a substantially rectangular cross-section to improve packing of the bands in a cage delivery catheter.
[0060] Additional wire coils may be wrapped around a portion of at least some of the bands for reinforcement of the bands, and increasing overall thickness of the bands. Wires may be wound around a square-shaped mandrel to form coils with substantially rectangular cross sections. The substantially rectangular cross sections of the wrapped bands can reduce overall thickness of the compressed frame by eliminating empty space between adjacent bands, and can allow a higher density of bands to be packed into the catheter.
[0061] When the self-expandable frame is deployed in a target location, the expanded frame frames the interior of the target location, leaving interior space for filling coils to be deployed thereafter. Alternatively, when the self-expandable frame is deployed in a target location, the frame functions as a backstop, preventing migration of coils to be deployed thereafter. The frame described herein can frame aneurysms much more expeditiously than conventional 3-dimensional framing coils. For example, a shorter distance is needed to push the compressed frame out of the catheter to frame an aneurysm, and framing the aneurysm can be completed more quickly using the frame described herein compared to conventional framing coils.
[0062] Various aspects of the invention described herein may be applied to any of the particular applications set forth below and for any other types of vaso-occlusive coils, cages, framing coils, etc. The invention may be applied as a standalone apparatus or method, or as part of a medical system. It shall be understood that different aspects of the invention can be appreciated individually, collectively, or in combination with each other.
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[0064] The plurality of bands 112 may be formed by laser cutting, chemical etching, or otherwise patterning of a tube (not shown). For example, slots can be laser cut along a length of the tube to form bands. The tube may be extruded from a monolithic block of material. The tube may have super-elastic and shape memory material properties. In some embodiments, the tube may be an elongated nitinol tube. At least some of the plurality of bands may have a substantially rectangular cross-section as a result of the laser cutting process. The substantially rectangular cross-section may be, for example a substantially square cross-section. In some embodiments, the tube may be laser cut such that each of the plurality of bands has a substantially rectangular cross-section. In other embodiments, the tube may be laser cut such that a first set of bands have a substantially rectangular cross-section, and a second set of bands have cross-sections that are non-rectangular. Non-limiting examples of non-rectangular cross-sections may include any polygonal shapes such as triangular, pentagonal, hexagonal, etc. In some alternative embodiments, at least some of the plurality of bands may have a substantially circular, oval, or semi-circular cross-section.
[0065] In some embodiments, at least one band may comprise a cross-section having varying shape, size, area, and/or longitudinal thickness profile. For example, a band may comprise a first end having a larger cross-sectional area than a second end. In some cases, a band may comprise a first end having a different cross-sectional shape than a second end. Such variations in cross-section of the band can be formed by preferential etching of the band, either alone or in conjunction with laser cutting.
[0066] In some embodiments, the plurality of bands may remain connected at an uncut first end of the tube after the tube has been laser cut. Proximal ends of the bands may be cut free from each other and then connected to each other using an attachment material including solders, welds, adhesives, epoxies, glues and the like. The proximal ends of the bands may be located at a second end of the tube opposite to the uncut first end of the tube. In some alternative embodiments, proximal ends of the bands remain connected at an uncut second end of the tube, and the uncut first and second ends of the tube may be located at opposite ends of the tube. In some further embodiments, the bands may be fully separated from each other after the tube has been laser cut, and the self-expandable frame may be formed by connecting first ends of the bands to each other at a first location (e.g. 114) and connecting second ends of the bands to each other at a second location (e.g. 116).
[0067] In some embodiments, the cage 100 may further comprise a wire coil 118 wrapped around a portion of at least some of the plurality of bands. The wire coil may be wrapped such that it conforms to the cross-section shape and/or longitudinal profile of the bands. For example, the wire coil may comprise a substantially rectangular shaped cross-section conforming to bands having substantially rectangular cross-sections. The wire coil may aid in radiofluoroscopy imaging and may comprise a radio opaque material. The radio opaque material may include metals such as platinum or platinum alloys. In some embodiments, the wire coil may be preferably constructed of platinum and its alloys in order to take advantage of the properties of these materials with respect to their ability to retain memory for shape, resistance to biological fluids, softness and non-ferromagnetic properties that will allow patients to undergo Mill procedures and pass through metal detectors. Although platinum and its alloys are preferred for the wire coil, those skilled in the art will appreciate that other materials and, in some instances, combinations of two or more materials including, for example, other metals and polymers, may also be utilized for the wire coil.
[0068] The wire coil can provide structural reinforcement to the bands. For example, the wire coil can be wrapped around a portion of some of the bands to achieve a predetermined thickness. Wrapping the wire coil around some of the bands can allow the bands to be packed more closely within a cage delivery catheter when the frame is constrained in its compressed configuration in the catheter. For example, a higher density of bands can be packed within the catheter with reduced empty space between adjacent compressed bands.
[0069] In some embodiments, the tube may be laser cut such that proximal ends of the bands are cut free from each other. A free end of one or more bands may be inserted into a lumen of one or more wire coils, and then the coil may be moved along the bands to a predefined location, prior to joining the free/open ends of the bands. As previously described, the open ends of the bands can be connected using any attachment material such as solders, welds, adhesives, epoxies, glues and the like.
[0070] Although
[0071] In some embodiments, a wire coil may be wrapped covering a substantial length of a band. A wire coil may consist of a single coil extending along the length of the band. Alternatively, a plurality of wire coils may be wrapped along a band and spaced apart from each other. The spacing between adjacent coils along a band can be fixed, uniform, staggered, or random. In some embodiments, a wire coil may be movable after it is wrapped around a band, and can slide to any location along the band. Optionally, a wire coil may be rigidly affixed (immobilized) after it is wrapped around a band. In some embodiments, the wire coil is not wrapped around a distal portion of a band, and may be placed a minimum distance away from the distal end of the band in order to allow the band to sufficiently bend or flex at its distal portion.
[0072] The frame 110 is configured to transition between a compressed configuration 102 and an expanded configuration 104. As shown in
[0073] The frame can transition between the compressed configuration and the expanded configuration with aid of a cage delivery catheter as described in more detail with reference to
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[0075] In some embodiments, the expanded frame may be separated from the pusher 122 via a deployment junction 124 after the frame has been fully deployed in the aneurysm. The junction 124 may be located at proximal ends of the plurality of bands releasably connecting the frame to the pusher. The expanded frame may be separated from the pusher through electrolytic or thermal means at the deployment junction, as known to those skilled in the art.
[0076] After the expanded frame has been separated from the pusher, the catheter and/or pusher may be withdrawn from the parent blood vessel, leaving the expanded frame in the aneurysm. The frame may be appropriately sized for the aneurysm under treatment, such that the size of the fully expanded frame exceeds the opening from the parent vessel into the aneurysm. This allows the expanded frame to be retained indefinitely within the aneurysm and will not present any loose ends that would extend out of the aneurysm.
[0077] In one optional embodiment, the frame may be retracted back into the catheter during the deployment process by pulling the pusher back into the catheter thereby causing the frame to follow. During retraction, the frame will transform from its expanded configuration back into a compressed configuration to enter the catheter.
[0078] In some further embodiments, the self-expandable frame need not be deployed via a severable junction, and may be mechanically deployed through the catheter in a similar fashion to a stent deployment. A cage delivery catheter may comprise a shaft having a lumen, a sidewall, at least one urging element formed in the sidewall, and a first filament disposed in the lumen. The self-expandable frame may comprise a second filament having a proximal end including a retention element which is disposed in the lumen of the shaft. The second filament may be fabricated from metal or from polymer, and may have a distal end coupled to a proximal end of the plurality of bands. The retention element may be releaseably retained within the lumen by the first filament which engages the retention element against the urging element in the sidewall to prevent the retention element from exiting a distal end of the shaft. The first filament may be proximally retracted to release the retention member from the urging element and release the plurality of bands from the distal end of the lumen. In some embodiments, the retention element may comprise a ball, and the sidewall of the catheter may comprise an aperture.
[0079] Referring back to
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[0081] In some embodiments, the frame may further comprise at least one dimpled portion 115 in its expanded configuration, for example as shown in
[0082] The cage may further comprise a pusher 122 coupled to the frame 110 via a deployment junction 124. The junction may be located at proximal ends of the plurality of bands, for example near the second location 116 of the frame, mated with the distal end of the pusher 122, as shown in the close-up view in
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[0085] As previously described, the wire coil may be wrapped around a selected number of bands. In some embodiments, the wire coil may be wrapped around all of the bands. Alternatively, the wire coil may be only wrapped around a single band. The wire coil may be wrapped continuously along a portion of a band. Alternatively, multiple wire coils may be wrapped continuously along a band and spaced apart from each other.
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[0088] Next, the tube may be laser cut, chemically etched, or otherwise patterned to form a plurality of elongated flexible bands 112 (
[0089] Next, a wire coil 118 may be loaded over an open end of at least some of the bands 112 (
[0090] After the wire coils are moved to predetermined locations along the bands, the free-hanging bands may be compressed (
[0091] The method of
[0092] In some embodiments, the tube shown in
[0093] In some embodiments, at least one band may comprise a cross-section having varying shape, size, area, and/or longitudinal thickness profile. Additionally or optionally, a band may comprise a first end having a different cross-sectional shape than a second end. The cross-section having the varying shape, size, area, and/or longitudinal thickness profile may be formed by preferential etching of the band.
[0094] In some embodiments, a band may comprise a tapered profile. The tapered profile may be formed by laser cutting, chemically etching, or otherwise patterning a tube of material described elsewhere herein. The tapered profile may be formed on a portion of the band, for example at or near a distal end of the band. Alternatively, the tapered profile may be formed along an entire length of a band. In some cases, the tapered profile may be formed on different portions of a band. For example, a band may comprise a plurality of tapered portions spaced longitudinally apart along a length of the band. The plurality of tapered portions may each have the same length or different lengths. The plurality of tapered portions may each have the same width or different widths. The plurality of tapered portions may each have the same thickness or different thicknesses. The plurality of tapered portions may each have the same tapering profile or different tapering profiles. Tapering profile(s) may be generated along one or more dimensions of a band (e.g., length, width, thickness, diameter, or cross-sectional area of a band). In some embodiments, a taper angle and/or width of the tapering profile(s) may be designed to achieve one or more of the following: (1) permit ease of manufacturing, (2) improve structural rigidity of the band(s), or (3) define the gaps/spacing between adjacent bands which may influence packaging of the bands in a catheter.
[0095] In some embodiments, a tapered profile may be formed at one or more ends of a band. For example, a band may have a tapered profile near its distal end. A proximal end of the band may or may not have a tapered profile.
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[0097] The band may also comprise a second portion 112-2 having a second width w2 along a predetermined length l2 near the first location 114 of the frame. The second portion 112-2 of the band may be wider/thicker than the first portion 112-1. The second portions 112-2 of the bands may be spaced apart by a gap 126-2. The gap 126-2 may be smaller than the gap 126-1.
[0098] The first and second portions may be connected via a third portion 112-3 having the tapered profile. As shown in
[0099] As previously described, the different widths of the bands can result in different sized gaps/spacing between adjacent bands. For example, as shown in
[0100] As previously described, a self-expandable frame may be generally spherical or ovoid in its expanded configuration. In some cases, the self-expandable frame may comprise at least one dimpled portion in its expanded configuration.
[0101] In some embodiments, the shape setting apparatus 140 may comprise one or more end rods 144 that can be used to form a dimpled portion in the expanded frame. For example, referring to
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[0103] The first location 114 of the expanded frame may have a dimpled portion 115 as described elsewhere herein. In the example of
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[0105] The cage and self-expandable frame in any of the embodiments described herein can be used as part of a system for occluding a vascular location. In some embodiments, a method of occluding a vascular location may comprise providing an cage, delivering the cage while constrained in its compressed configuration to a target site in the vasculature, releasing the cage from constraint so that it expands to its expanded configuration at the target location, and thereafter delivering embolic coils to the site.
[0106] The cage can be delivered by positioning a distal end of a cage delivery catheter at a target location in a patient's vascular, and advancing the cage in its compressed configuration through a lumen of the cage delivery catheter. The target location may be an aneurysm. Optionally, the target location may be a blood vessel lumen. The vascular cage can be released from constraint by releasing the cage from the distal end of the cage delivery catheter so that the cage self-expands at the target location. In some embodiments, the method of occluding the vascular location may further comprise delivering coils into the interior volume of the cage after the cage has been released.
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[0108] As shown in
[0109] Referring to
[0110] After a frame 190 has been formed (by wrapping the bands 184 around the expansion device 182), the two bent ends of the mandrel 188 and the proximal and distal portions 186-1/186-2 of the shape set hypotube may be cut, in order to allow removal/release of the frame 190 from the expansion device 182.
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[0114] Although certain embodiments and examples are provided in the foregoing description, the inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses, and to modifications and equivalents thereof. For example, the apparatus and methods described herein can be applied to any type of vaso-occlusive devices or methods for making or using such devices. Thus, the scope of the claims appended hereto is not limited by any of the particular embodiments described below. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or devices described herein may be embodied as integrated components or as separate components.
[0115] For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein.
[0116] As used herein A and/or B encompasses one or more of A or B, and combinations thereof such as A and B. It will be understood that although the terms first, second, third etc. may be used herein to describe various elements, components, regions and/or sections, these elements, components, regions and/or sections should not be limited by these terms. These terms are merely used to distinguish one element, component, region or section from another element, component, region or section. Thus, a first element, component, region or section discussed below could be termed a second element, component, region or section without departing from the teachings of the present disclosure.
[0117] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present disclosure. As used herein, the singular forms a, an and the are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms comprises and/or comprising, or includes and/or including, when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components and/or groups thereof.
[0118] Furthermore, relative terms, such as lower or bottom and upper or top may be used herein to describe one element's relationship to other elements as illustrated in the figures. It will be understood that relative terms are intended to encompass different orientations of the elements in addition to the orientation depicted in the figures. For example, if the element in one of the figures is turned over, elements described as being on the lower side of other elements would then be oriented on the upper side of the other elements. The exemplary term lower can, therefore, encompass both an orientation of lower and upper, depending upon the particular orientation of the figure. Similarly, if the element in one of the figures were turned over, elements described as below or beneath other elements would then be oriented above the other elements. The exemplary terms below or beneath can, therefore, encompass both an orientation of above and below.
[0119] It should be understood from the foregoing that, while particular implementations have been illustrated and described, various modifications can be made thereto and are contemplated herein. It is also not intended that the invention be limited by the specific examples provided within the specification. While the invention has been described with reference to the aforementioned specification, the descriptions and illustrations of the preferable embodiments herein are not meant to be construed in a limiting sense. Furthermore, it shall be understood that all aspects of the invention are not limited to the specific depictions, configurations or relative proportions set forth herein which depend upon a variety of conditions and variables. Various modifications in form and detail of the described embodiments will be apparent to a person skilled in the art. It is therefore contemplated that the invention shall also cover any such modifications, variations and equivalents.