Implant delivery assembly having distal protection - Patents.com

Abstract

A delivery system for deploying a medical implant includes a delivery wire assembly disposed within a delivery catheter lumen, the assembly having an implant loading region configured to secure the implant when the assembly is constrained within the delivery catheter lumen and the implant is in a compressed configuration, the assembly further includes an implant distal protection portion having a central portion coupled to the assembly distal to the implant loading region and a peripheral portion extending proximally from the central portion to at least partially cover a distal end of the implant when the assembly, the implant and the distal protection portion are constrained within the catheter lumen, the peripheral portion remaining extended proximally when the implant assumes an expanded configuration after being released from the catheter lumen, and the peripheral portion of the distal protection portion includes a plurality of stems, each having a respective petal-shaped member.

Description

[Technical field]

[0001]

[0001] The present disclosure relates generally to a minimally invasive assembly used to deliver a medical implant. More specifically, the present disclosure relates to a delivery assembly for delivering a medical implant, such as a tubular stent or a flow diverter, to a target implantation site in a patient's blood vessel. [Background technology]

[0002]

[0002] The use of intravascular implants, such as stents, stent grafts, flow diverters, aneurysm occlusion devices, inferior vena cava filters, etc., has become an effective method of treating many types of vascular diseases. In general, a suitable intravascular implantable device is inserted into a patient's vasculature and guided through the blood vessels to a target implantation site using a delivery system, such as a catheter having a delivery lumen. Using currently available delivery devices, virtually any target site in a patient's vasculature, including the coronary, cerebral, and peripheral vessels, can be accessed.

[0003]

[0003] A minimally invasive delivery device includes a catheter that is percutaneously introduced into a patient's blood vessel via a guidewire, and the open distal end of the catheter is guided to a target implantation site using known techniques. A medical implant is then deployed through the delivery lumen of the catheter in a compressed (i.e., reduced diameter) delivery configuration, and then introduced into the lumen of the blood vessel through the distal end opening of the catheter. For example, a self-expanding implant such as a stent is delivered in an elastically compressed state while confined within a tubular catheter delivery lumen, and then elastically expands to engage the inner wall of the blood vessel when deployed outward from the open distal end of the catheter. The expanded and enlarged stent supports and reinforces the vessel wall, thereby maintaining the blood vessel in an open and unobstructed state.

[0004]

[0004] Medical implants can have a variety of sizes and shapes. For example, stents and some flow diverters typically assume an expanded, substantially tubular configuration when deployed in a patient's blood vessel. Additionally, medical implants can be formed from a variety of materials, including polymers (e.g., non-biodegradable and biodegradable plastics) and metals. Medical implants can be formed from shape memory or superelastic materials, such as shape memory metals (e.g., shape memory nitinol) and polymers (e.g., polyurethane). Such shape memory implants can be induced (e.g., by temperature, electric field, magnetic field, or light) to assume a certain shape (e.g., a radially expanded shape) after delivery to a treatment site. Superelastic embolic materials, such as superelastic nitinol, assume a certain shape after delivery without the need for an inductive stimulus. Other commonly used materials include stainless steel, platinum, and elgiloy. Drug delivery implants can carry bioactive or therapeutic agents and / or the surface of the device can be coated with bioactive or therapeutic agents. Commonly used medical implants, such as stents, stent grafts, flow diverters, etc., may be constructed from multiple filaments (e.g., wires) that are braided or woven into a predetermined (e.g., tubular) shape, or may be formed from laser cut tubes.

[0005]

[0005] Known delivery systems may include a retaining sleeve to control release or a cover to protect the ends of the implant during deployment, as shown and described (by way of example) in U.S. Patent Nos. 6,478,814, 6,830,575 and 8,591,566. Such sleeves / covers may include winged or separate members that may be more difficult to manufacture and may increase the resistance or frictional forces imparted by the device assembly when pushed through a delivery catheter, adversely affecting the overall performance of the delivery system.

[0006]

[0006] Therefore, there remains a need to provide an implant delivery system for delivering self-expanding implants that facilitates protection of the implant while avoiding or minimizing increased resistance or frictional forces through the delivery catheter.

[0007]

[0007] By way of example, Figure 1 shows an implant delivery system 100 constructed in accordance with one embodiment of the disclosed invention. The implant delivery system 100 generally comprises an elongated tubular delivery catheter 120 having a proximal end 130, a distal end 160 and a lumen 125 extending therebetween, the lumen 125 of the delivery catheter 120 being in communication with the respective open proximal and distal ends of the delivery catheter 120. The delivery catheter 120 is coaxially disposed within, and movable relative to, an outer sheath 180 that is used to help position the distal end 160 of the delivery catheter 120 within a target portion of a blood vessel. The proximal end 130 of the delivery catheter 120 includes a fluid port 150 (distal to a proximal opening of the outer sheath 180 through which the delivery catheter 120 is inserted) that is used to introduce fluid into the lumen 125. The fluid delivery port 150 remains outside the patient's body so as to be accessible to a physician / operator when the implant delivery system 100 is inserted into the patient's vasculature. The distal portion 160 of the delivery catheter 120 has a size and dimension to access a remote location within a vasculature, such as within a neurovasculature, and may have a smaller diameter (or profile) than the proximal portion 130.

[0008]

[0008] The implant delivery system 100 further includes an implant delivery wire assembly 300 (described in more detail below in conjunction with Figures 2A-2D) that includes a core wire 350 that is pushed through a lumen 125 of the delivery catheter to deliver an implant 200 (not shown in Figure 1) held on a distal end of the core wire 350 to a target site within a patient's blood vessel. As shown in Figure 1, the core wire 350 is inserted through a proximal end opening of the delivery catheter 120 and pushed through the delivery lumen 125 such that an atraumatic distal tip 380 (e.g., a soft coil member) attached to the distal end of the core wire 350 extends outwardly from the distal end opening of the delivery catheter 120.

[0009]

[0009] The outer sheath 180 may be introduced into the blood vessel over a previously introduced guidewire (not shown) (known as an over-the-wire configuration), or alternatively, may be introduced in a "rapid exchange" configuration in which the guidewire extends from a guidewire port (not shown) through only a distal portion of the outer sheath 180, as is well known. The delivery catheter 120 is then introduced over the guidewire or otherwise through the outer sheath, also as is well known. The outer sheath 180 includes a radiopaque marker 355 adjacent the open distal end of the sheath to aid in its positioning at the target location in the blood vessel.

[0010]

[0010] The delivery catheter 120 may be constructed of a suitable polymeric material, metal and / or alloy, such as polyethylene, stainless steel or other suitable biocompatible material or combinations thereof. In some cases, the proximal portion 130 may include a reinforcing layer, such as a braided or coiled layer, to improve pushability. The delivery catheter 120 may include one or more transition regions between the proximal portion 130 and the distal portion 160. The distal end 160 may have an outer diameter smaller than that of the proximal portion 130 to reduce the profile of the distal end 160 and facilitate navigation of the distal end 160 extending from the distal opening of the outer sheath 180 through tortuous blood vessels. The proximal end 130 may be formed from a stiffer material than the distal portion 160 of the delivery catheter 120 such that the proximal portion 130 has sufficient pushability to be advanced through the patient's vasculature, while the distal end 160 may be formed from a more flexible material such that the distal end 160 remains flexible to more easily track over a guidewire to access remote locations in tortuous regions of the blood vessel. As best shown in FIG. 2A, the tapered radiopaque marker 455 and atraumatic tip 457 are each positioned proximate the distal end opening 452 of the delivery catheter 120.

[0011] 2A-2D show an implant 200, which may be a stent, flow diverter, or other type of vascular implant, held on a distal portion of a core wire 350. The implant 200 may be constructed of a variety of biocompatible materials, such as stainless steel, elgiloy, nickel, titanium, nitinol, shape memory polymers, or combinations thereof, and may be constructed using well-known techniques, such as by etching or cutting a pattern from a tube or sheet of stent material, or by weaving / braiding one or more wires or ribbons into the desired shape and pattern. The implant 200 may include additional components that are welded, bonded, or otherwise engaged with one another, and may optionally include non-porous, non-permeable biocompatible materials, covers, and the like.

[0012]

[0012] As shown in Figure 2D, the implant 200 is generally tubular and has a proximal portion 220 and a distal portion 240 with a lumen 260 extending therebetween. In Figures 2A-2D, the implant 200 is shown in a compressed, elongated delivery configuration and is radially constrained within the lumen 125 of the delivery catheter 120. When the implant 200 is deployed outwardly from the distal end opening of the delivery catheter 120 (i.e., when no longer radially constrained within the delivery catheter 120), the implant 200 is preferably biased to self-expand radially outwardly to the expanded, deployed configuration.

[0013] 2A and 2B, the core wire 350 of the delivery wire assembly 300 is coaxially disposed within the delivery catheter lumen 125, and the implant 200 is coaxially disposed around the core wire 350 and constrained within the delivery catheter lumen 125. In particular, the core wire 350 is axially movable relative to the delivery catheter 120, and the delivery wire assembly 300 is configured to engage the implant 200 as the core wire 350 translates axially through the delivery catheter lumen 125 to deliver the implant 200 to a target implantation site within a blood vessel. The interaction between the delivery wire assembly 300 and the implant 200 is described in further detail below.

[0014] To aid in positioning the core wire 350 and implant 200 relative to the delivery catheter 120, a radiopaque marker 360 (e.g., a laser etched radiopaque band or any other suitable marker) is preferably placed along the distal portion of the core wire 350. In the illustrated embodiment, a coil 357 is placed around the core wire 350 to provide structural support just proximal to the implant 200. A radiopaque marker band 360 is placed on the distal portion 358 of the coil 357 to indicate the location of the proximal end 220 of the implant 200. An epoxy adhesive 376 is used to attach the marker 360 to the core wire 350.

[0015] 2B and 2C, a re-covering pad 370 is placed around the core wire 350 distal to the coil 357, and an implant re-covering bumper 375 is attached to the core wire 350 at the distal end of the re-covering pad 370. An epoxy adhesive 376 is used to attach the re-covering bumper to the core wire 350. This region of the core wire 350 where the implant 200 is loaded is referred to herein as the implant loading region. In particular, the proximal portion 220 of the implant 200 is placed on the respective re-covering pad 370 and re-covering bumper 375, and the distal end of the distal portion 240 of the implant 200 is covered by a distal protection feature 500 (FIG. 2A) attached to the core wire 350 and secured between the respective proximal and distal locking members 550 and 550. In Figure 2A, only the distal locking member 550 is shown as it is obscured by the implant distal protection feature 500. An atraumatic distal tip 380 (e.g., a soft coil member) is attached to the core wire proximal to the distal locking member 550 (Figure 2B). Summary of the Invention

[0016]

[0016] In one embodiment of the disclosed invention, a delivery system is provided for deploying an implant at a target site in a mammalian blood vessel, the implant having a compressed delivery configuration and an expanded deployment configuration. The delivery system includes a delivery catheter having a lumen and an elongated delivery wire assembly at least partially disposed within the delivery catheter lumen, the delivery wire assembly having an implant loading region configured to be translatable relative to the delivery catheter and to secure the implant when a distal portion of the delivery wire assembly including the implant is constrained within the delivery catheter lumen and the implant is in the compressed delivery configuration. The delivery system further includes an implant distal protector including a central portion coupled to the delivery wire assembly distal to the implant loading region and a peripheral portion extending proximally from the central portion to at least partially cover a distal end of the implant when the distal portion of the delivery wire assembly including the implant and the implant distal protector is constrained within the delivery catheter lumen. The peripheral portion of the implant distal protection is configured to expand when the peripheral portion of the implant distal protection is no longer constrained by the delivery catheter. Further, the peripheral portion of the implant distal protection is configured not to invert from a proximal-facing direction to a distal-facing direction, such that when the implant assumes the expanded, deployed configuration after being released from the delivery catheter lumen and no longer covered by the peripheral portion of the implant distal protection, the peripheral portion of the implant distal protection remains extending in the proximal-facing direction. Further, the peripheral portion of the implant distal protection comprises a plurality of circumferentially spaced elongate stems, each stem comprising a respective petal-shaped member, the plurality of stems extending from the central portion.

[0017]

[0017] In various embodiments, respective petals are disposed on and / or cover each of the elongated stems of the peripheral portion of the implant distal protection portion.

[0018]

[0018] In one embodiment, each of the petal-shaped members comprises a first petal-shaped member positioned at approximately 80% to approximately 90% of the total length of the respective long stem or covering approximately 80% to approximately 90% of the total length of the stem, a second petal-shaped member positioned at approximately 60% to approximately 50% of the total length of the respective long stem or covering approximately 60% to approximately 50% of the total length of the stem, and a third petal-shaped member positioned at approximately 40% to approximately 30% of the total length of the respective long stem or covering approximately 40% to approximately 30% of the total length of the stem.

[0019]

[0019] In some embodiments, the petals are substantially evenly spaced circumferentially around the delivery wire assembly. The petals comprise arcuate, annular strips or concave configurations.

[0020]

[0020] In another embodiment, the central portion of the implant distal protection portion is fixedly attached to the delivery wire assembly in such a manner that the implant distal protection portion is non-rotatable relative to the delivery wire assembly. Alternatively, the central portion of the implant distal protection portion is attached to the delivery wire assembly in such a manner that the implant distal protection portion is rotatable relative to the delivery wire assembly.

[0021] In one embodiment, when the distal portion of the delivery wire assembly including the implant and the implant distal protection portion is constrained within the delivery catheter lumen, the implant distal protection portion covers about 20% of the total length of the implant. In another embodiment, when the distal portion of the delivery wire assembly including the implant and the implant distal protection portion is constrained within the delivery catheter lumen, the implant distal protection portion covers about 10% to about 20% of the total length of the implant. In yet another embodiment, when the distal portion of the delivery wire assembly including the implant and the implant distal protection portion is constrained within the delivery catheter lumen, the implant distal protection portion covers about 5% to about 10% of the total length of the implant. In a further embodiment, when the distal portion of the delivery wire assembly including the implant and the implant distal protection portion is constrained within the delivery catheter lumen, the implant distal protection portion covers about 5% or less of the total length of the implant.

[0022]

[0022] Optionally, the implant distal protection portion is configured to exert a negligible or insignificant force on the distal portion of the implant when the implant expands from the compressed delivery configuration to the expanded deployed configuration.

[0023]

[0023] Optionally, the implant distal protection portion is configured to expand sequentially from the compressed delivery configuration to the expanded deployed configuration, with the first petal-shaped member expanding, then the second petal-shaped member expanding, and finally the third petal-shaped member expanding.

[0024]

[0024] Optionally, the implant distal protection portion substantially retains a compressed delivery configuration after the implant distal protection portion radially expands and is no longer constrained by the delivery catheter.

[0025]

[0025] Optionally, the implant distal protection portion is configured so as not to invert in the distally facing direction as the implant expands.

[0026]

[0026] Optionally, the implant distal protection portion is configured to be pulled back into the delivery catheter without reversing from the proximal-facing direction to the distal-facing direction.

[0027]

[0027] Optionally, the implant distal protection portion comprises a biocompatible material having a thickness of about 0.0006 inches and a length of about 0.0173 inches.

[0028]

[0028] Optionally, each of the petals includes a first petal disposed at about 60% to about 90% of the total length of the stem, or covering about 60% to about 90% of the total length of the stem, and a second petal disposed at about 50% to about 30% of the total length of the stem, or covering about 50% to about 30% of the total length of the stem. In this embodiment, the implant distal protection portion is configured to sequentially expand from the compressed delivery configuration to the expanded deployment configuration, with the first petal expanding first and then the second petal expanding.

[0029]

[0029] Optionally, each of the petals comprises three or more respective petals, each of the petals being disposed at or covering a different percentage of the length of their respective elongate stems. In this embodiment, the implant distal protection is configured to sequentially expand from the compressed delivery configuration to the expanded deployed configuration, causing multiple of the petals to expand in sequence.

[0030]

[0030] Other and further aspects and features of the embodiments of the invention disclosed herein will become apparent from the following detailed description considered in conjunction with the accompanying drawings. [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a side view of an implant delivery system (prior art). [Diagram 2]

[0032] 2A-2E are partial cross-sectional, perspective and exploded views of a delivery wire assembly (prior art) of the implant delivery system of FIG. 1, showing portions of the system in greater detail. [Diagram 3]

[0033] 3A and 3B are partial cross-sectional side and detailed views of a delivery wire assembly of an implant delivery system showing an implant distal protection according to one inventive embodiment of the present disclosure. [Figure 4]

[0034] 4A and 4B are end views of an implant distal protection part according to an embodiment of the present disclosure, FIG. 4C is a perspective side view of an implant distal protection part according to an embodiment of the present disclosure, FIG. 4D is a cross-sectional view of a petal according to an embodiment of the present disclosure, and FIG. 4E is a perspective side view of an implant distal protection part according to an embodiment of the present disclosure. [Diagram 5]

[0035] 5A and 5B are end views of an implant distal protection portion according to an alternative embodiment of the disclosed invention, and FIG 5C is a perspective side view of an implant distal protection portion 800 according to an alternative embodiment of the disclosed invention. [Figure 6]

[0036] FIG. 6 is an alternative implant distal protection section similar to FIGS. 5A-5C. [Figure 7]

[0037] 7A and 7B are another alternative implant distal protection according to another embodiment of the disclosed invention. [Figure 8]

[0038] FIG. 8 is yet another alternative implant distal protection according to a further embodiment of the disclosed invention. [Figure 9]

[0039] 9A-9D are cross-sectional, side and perspective views of the implant distal protection of FIGS. 4A-4E with the delivery wire assembly shown loaded into a delivery catheter 120 according to an embodiment of the disclosed invention. [Figure 10]

[0040] 10A-10H are side and perspective views of the implant distal protection portion of FIGS. 4A-4E illustrating delivery and deployment of the implant to a target site within a blood vessel using the implant delivery system of FIGS. 1-3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032]

[0041] For the following defined terms, these definitions shall be applied, unless a different definition is given in the claims or elsewhere in this specification.

[0033]

[0042] In this specification, all numerical values ​​are deemed to be modified by the term "substantially" or "about", whether or not expressly indicated. The terms "substantially" and "about" refer to a range of numerical values ​​that one of ordinary skill in the art would consider equivalent to the recited parameter, structure or value (i.e., having the same function or result). In many cases, the terms "about" and "substantially" include numerical values ​​that are rounded to the nearest significant figure. The recitation of numerical ranges by endpoints includes all numerical values ​​within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0034]

[0043] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or" unless the content clearly dictates otherwise.

[0035]

[0044] As used herein and in the appended claims, the terms "proximal" and "proximally" (and similar terms) when used to describe the relative position, location or direction of a structure or movement of an implant delivery system that is toward the outside of a patient's body; and "distal" and "distally" (and similar terms) when used to describe the relative position, location or direction of a structure or movement of an implant delivery system that is extended deepest into a patient's body.

[0036]

[0045] Various embodiments of the presently disclosed invention are described below with reference to the drawings. The figures are not necessarily drawn to scale, the relative scale of selected elements may be exaggerated for clarity, and elements having similar structure or function are represented by like reference numerals throughout the figures. It should also be understood that the figures are intended only to facilitate the description of the embodiments, and are not intended as an exhaustive description of the presently disclosed invention, or as limiting its scope, which is defined solely by the appended claims and their equivalents.

[0037]

[0046] Moreover, each illustrated embodiment of the invention of the present disclosure need not have all of the illustrated features, and a feature, aspect, or advantage described in connection with a particular embodiment is not necessarily limited to that embodiment and may be implemented in other embodiments even if not so illustrated.

[0038]

[0047] FIG. 3A illustrates an implant delivery wire assembly 300 of an implant delivery system 100 including an implant distal protection portion 700 according to one embodiment of the present disclosure. A core wire 350 is pushed through a delivery catheter lumen 125 (FIG. 1) to deliver an implant 200 held at a distal end of the core wire 350 to a target site within a patient's blood vessel. The implant 200 may be a stent, flow diverter, or other type of vascular implant, and may be constructed of a variety of biocompatible materials, as previously described. In FIG. 3A, the implant 200 is shown in a compressed, elongated delivery configuration disposed (i.e., radially constrained) within the lumen 125 of the delivery catheter 120. When the implant 200 is deployed from the distal end opening of the delivery catheter 120 (i.e., no longer radially constrained within the delivery catheter 120), it is preferably biased to self-expand radially outwardly to an expanded, deployed configuration. The core wire 350 of the delivery wire assembly 300 is coaxially disposed within the delivery catheter lumen 125, and the implant 200 is coaxially disposed around the core wire 350, which is also constrained within the delivery catheter lumen 125. A radiopaque marker 360 (e.g., a laser etched radiopaque band or any other suitable marker) is preferably disposed along a distal portion of the core wire 350 to aid in positioning the core wire 350 and implant 200 relative to the delivery catheter 120. A coil 357 is disposed around the core wire 350 to provide structural support just proximal to the implant 200. A tapered radiopaque marker 455 and an atraumatic tip 457 are each disposed proximate the distal end opening 452 of the delivery catheter 120. In FIG. 3A, the distal locking member 750 is shown as the proximal locking member 750′ is hidden by the implant distal protection portion 700. In the illustrated embodiment, the implant distal protection portion 700 is fixedly attached to the core wire 350 by a locking member 750 so that the implant distal protection portion does not rotate relative to the core wire 350 .

[0039]

[0048] In an alternative embodiment, the implant distal protector 700 may be attached to a collar (not shown) that is still fixed in its relative longitudinal position on the core wire 350 by the locking member 750 in a manner that allows the collar, and thus the implant distal protector 700, to rotate relative to the core wire 350 and the locking member 750. The rotatable implant distal protector 700 is configured to allow torque transmission to the distal end (e.g., the atraumatic distal tip 380) of the core wire 350, thereby allowing for vessel selection and facilitating guidance of the delivery wire assembly 300 to the target implantation site. When the implant distal protector 700 rotates relative to the core wire 350, externally induced (e.g., by the patient's anatomy, user, clinician) relative twisting between the delivery catheter 120 and the core wire 350 is avoided or significantly minimized, preventing the accumulation of twisting energy that would adversely affect the deployment of the implant 200. Thus, the rotatable implant distal protection portion 700 is configured to prevent torsional energy from accumulating in the delivery wire assembly 300 and the implant 200 when the assembly 300 and the implant 200 are in a delivery configuration (e.g., a radially constrained state) disposed within the lumen 125 of the delivery catheter 120.

[0040]

[0049] Additionally, an atraumatic distal tip 380 (e.g., a soft coil member) is attached to the core wire proximate the distal locking member 550 (FIGS. 3A and 3B). FIG. 3B shows a detailed view of the implant distal protector 700 in a compressed, elongated delivery configuration (i.e., radially constrained). The implant distal protector 700 is described in further detail below.

[0041]

[0050] 4A-4E show an implant distal protection portion 700 of a delivery wire assembly 300 according to one embodiment of the disclosed invention. FIGS. 4A and 4B are end views of the implant distal protection portion 700 in an unconstrained deployed configuration, FIG. 4C is a perspective side view of the implant distal protection portion 700 in an unconstrained deployed configuration; FIG. 4D is a cross-sectional view of a petal in a radially constrained delivery configuration, and FIG. 4E is a perspective side view of the implant distal protection portion 700 in a radially constrained delivery configuration. The implant distal protection portion 700 is constructed of a biocompatible material such as TFN, ePTFE, polymer, Nitinol, etc. In one embodiment, the implant distal protection portion 700 comprises a reinforcing member 710 having three elongated arms, ribs, or stems 715a-c extending from a central portion 712. The central portion 712 includes an opening 714 that receives or is disposed about the core wire 350 of the implant delivery wire assembly 300. The central portion 712 and the opening 714 may each have a circular configuration, as shown in FIGS. 4A-4E, or any other suitable configuration (not shown). The stems 715a-715c extend from and are disposed about the central portion 712 of the implant distal protection portion 700. Each stem 715a-715c has a proximal section 715′, a middle section 715″, and a distal section 715′″, respectively. The proximal section 715′ of each of the stems 715a-715c is coupled to the central portion 712 of the implant distal protection portion 700. The central portion 712 and the stems 715a-715c are constructed of Nitinol or any other suitable superelastic material.

[0042]

[0051] 4A and 4B, stems 715a-715c are symmetrically disposed about the y-axis around central portion 712, e.g., stem 715a is at an angle θ about 120° away from stem 715b, which is also at an angle θ about 120° away from stem 715c, which is also at an angle θ about 120° away from stem 715c. Note that stems 715a-715c may be disposed in an asymmetric configuration about central portion 712 at any suitable angle θ separation (not shown).

[0043]

[0052] In the embodiment of Figures 4A-4E, the implant distal protection portion 700 further comprises three petals (or "petals") 720a-720c disposed on each of the respective stems 715a-715c. The petals 720a-720c are each comprised of a substantially uniform layer of ePTFE having a thickness of about 0.0006 inches to about 0.0012 inches. The petals 720a-720c are comprised of a biocompatible material such as TFN, ePTFE, a polymer, combinations thereof, and the like. For example, a commercially available polyimide (PI) film with an FEP coating may be used on the exterior or interior of the ePTFE material of the petals 720a-720c. Additionally or alternatively, the FEP coated PI film may be incorporated between the ePTFE layers during the sintering process of the manufacture of the petals 720a-720c.

[0044]

[0053] As shown in Figures 4A and 4B, each of the petals 720a-720c may be disposed on or cover about 40% to about 90% of each of their respective stems 715a-715c. As better seen in the embodiment of Figure 4A, which shows the outlines of the stems 715a-715c within the petals 720a-720c, the petal 720a is disposed on or covers about 80% to 90% of the stem 715a, the petal 720b is disposed on or covers about 50% to 60% of the stem 715b, and the petal 720c is disposed on or covers about 40% to 30% of the stem 715c. Thus, proximal section 715' of stem 715a-715c is not covered by petals 720a-720c, a small portion of mid-section 715'' of 715b is not covered by petal 720b, and a majority of mid-section 715'' of 715c is not covered by petal 720c.

[0045]

[0054] 4A-4E, petals 720a-720c have the same length, but petal 720c extends further distally than petals 720a-720b, which extends further distally than petal 720a. Petals 720a-720b extend "distally" relative to central portion 712 of implant distal protection portion 700, but, as described in more detail below, when implant distal protection portion 700 is unconstrained within delivery catheter 120, petals 720a-720b are directed proximally.

[0046]

[0055] It should be appreciated that the petals 720a-720c may include different lengths and may be arranged about the same section on their respective stems 715a-715c to create similar implant distal protection having different distally extending petals. The different distally extending petals 720a-720c of Figures 4A-4E are configured to cover the implant with minimal material for better cleaning during delivery of the implant 200. Additionally, the different distally extending petals 720a-720c of the implant distal protection portion 700 are configured to allow each of the petals 720a-720c to be deployed sequentially upon exiting the delivery catheter 120 (e.g., as the delivery catheter 120 is withdrawn proximally relative to the core wire 350, or as the core wire 350 is pushed distally relative to the delivery catheter 120, or as a portion of each is performed such that the implant distal protection portion 700 is exposed from the distal end opening 452 of the delivery catheter 120), thereby avoiding or minimizing the risk of the petals 720a-720c becoming entangled and / or avoiding or minimizing potential damage to the implant distal protection portion 700 (e.g., inability to radially expand). The sequential radial expansion of petals 720a-720c (e.g., no longer radially constrained by delivery catheter 120) is in the order of i) first petal 720a, then ii) petal 720b, and finally, iii) petal 720c, as described in further detail below.

[0047]

[0056] As can be better seen in Figures 4C-4D, which show perspective side and cross-sectional views of implant distal protection 700, petals 720a-720c in Figures 4A-4E have an arcuate configuration along the petal length L. For example, Figure 4D shows a cross-sectional view of petal 720b, which has a concave configuration of an arcuate annular strip, as can also be seen in Figure 4E. Figure 4E shows a perspective side view of implant distal protection 700 in a radially constrained delivery configuration, further illustrating petals 720a-720c extending differently distally relative to central portion 712, with petal 720c extending further distally than either of the other petals 720a-720b, and petal 720b extending further distally than petal 720a.

[0048]

[0057] 5A-5C show an alternative implant distal protection portion 800 of a delivery wire assembly 300 according to a further embodiment of the disclosed invention. FIGS. 5A and 5B are end and partial views of the implant distal protection portion 800 in an unconstrained deployed configuration; FIG. 5C is a perspective side view of the implant distal protection portion 800 in a radially constrained delivery configuration. Similar to the implant distal protection portion 700 of FIGS. 4A and 4B, the implant distal protection portion 800 comprises a reinforcing member 810 having three elongated arms, ribs or stems 815a-c extending from a central portion 812. The central portion 812 includes an opening 814 configured to receive or be disposed around the core wire 350 of the implant delivery wire assembly 300.

[0049]

[0058] Additionally, the implant distal protection portion 800 of Figures 5A-5C is similar to the implant distal protection portion 700 of Figures 4A and 4B, except that the implant distal protection portion 800 of Figures 5A-5C has petals 820a-820c constructed from a unitary thin substantially uniform layer of ePTFE or other suitable material. As better shown in Figure 5B, the petals 820a-820c merge into a central portion 812 configured to be coupled to the core wire 350. As shown in Figures 5B and 5C, when the implant distal protection portion 800 is unconstrained within the delivery catheter 120, the petals 820a-820c extend generally radially outward from the central portion 812 and are directed proximally. Petals 820a-820c are comprised of a substantially uniform layer of ePTFE or other suitable material, however, implant distal protection portion 800 of FIGS. 5A-5C also has petals 820a-820c that extend differently distally relative to central portion 812, with petal 820c extending further distally than the other petals, particularly petal 820b, as can be better seen in FIG. 5C.

[0050]

[0059] 6 illustrates another alternative implant distal protector 900 of a delivery wire assembly 300 according to another embodiment of the disclosed invention. The implant distal protector 900 includes three elongated arms, ribs or stems 915a-915c extending from a central portion 912. The implant distal protector 900 of FIG. 6 is similar to that of FIGS. 5A-5C, except that a single, thin, substantially uniform layer of ePTFE material forming petals 920a-920c is disposed more about the central portion 912.

[0051]

[0060] 7A and 7B show yet another alternative implant distal protection portion 1000 of a delivery wire assembly 300 according to another embodiment of the disclosed invention. The implant distal protection portion 1000 of FIG. 7A and FIG. 7B has three petals 1020a-c arranged about a central portion 1012. The implant distal protection portion 1000 of FIG. 7A and FIG. 7B is similar to that of FIG. 6, except that the three elongated arms, ribs or stems 1015a-c extending from the central portion 1012 are shorter than the stems 915a-c of FIG. 6. Additionally, FIG. 7B shows a distal locking member 750 (also shown in FIG. 3A and FIG. 3B) and a proximal locking member 750′ coupled to the implant distal protection portion 1000. Additionally, in the implant distal protection portion 1000 (as can be better seen in FIG. 7B), the stems 1015a-1015c are disposed above or beside the petals 1020a-1020c.

[0052]

[0061] FIG. 8 illustrates an alternative implant distal protection portion 1100 of a delivery wire assembly 300 according to another embodiment of the disclosed invention. Similar to the implant distal protection portion 700 of FIGS. 4A-4E, FIG. 9 includes petals 1120a-c that extend differently distally relative to a central portion 1112, with petal 1120c extending further distally than either of the other petals 1120a-b, and petal 1120b extending further distally than petal 1120a. The implant distal protection portion 1100 further includes a reinforcing member 1110 having three elongated bifurcated arms, ribs, or stems 1115a-c extending from the central portion 1112. The central portion 1112 includes an opening 1114 configured to receive or be disposed around a core wire 350 of the implant delivery wire assembly 300. The bifurcated stems 1115a-1115c extend from and are disposed around the central portion 1112 of the implant distal protection portion 1100. As shown in Fig. 8, each stem 1115a-1115c bifurcates into two branches with a petal 1120a-1120c disposed between each of the respective branches. For example, the stem 1115a bifurcates into a first branch 1115a(i) and a second branch 1115a(ii) to form a "U" shaped configuration and the petal 1120a is disposed between the branches 1115a(i) and 1115a(ii). The bifurcated stems 1115a-1115c of FIG. 8 are configured to provide additional structural support to the petals 1120a-1120c, enabling the petals to orient proximally when the implant distal protection portion 1100 is not constrained within the delivery catheter 120.

[0053]

[0062] It should be understood that the petals of Figures 5A-8 have a concave cross-sectional configuration of an arcuate annular strip, as shown in Figure 4D. Other suitable cross-sectional configurations of the petals of Figures 5A-8 may be contemplated. In other embodiments (not shown), the implant distal protection portion 700 may include more or less than three stems and / or petals configured to be sequentially deployed, as described in further detail below.

[0054]

[0063] 9A-9D illustrate forward loading of a delivery wire assembly 300 into a delivery catheter 120 according to one embodiment of the disclosed invention. The implant distal protector 700 of FIGS. 4A-4E is illustrated in FIGS. 9A-9D as an exemplary distal protector used to load a delivery wire assembly 300 including an implant 200 into a delivery catheter 120. It should be understood that any of the implant distal protectors disclosed in the alternative embodiments of FIGS. 5A-8 may be used to load a delivery wire assembly 300 including an implant 200 into a delivery catheter 120.

[0055]

[0064] 9A shows the distal end of the delivery wire assembly 300 including the implant distal protection portion 700 and the implant 200 immediately prior to loading into the delivery catheter 120, with the petals 720a-720c of the implant distal protection portion 700 shown extending generally proximally in a radially unconstrained configuration. As previously discussed, the implant distal protection portion 700 includes petals 720a-720c that extend differently (e.g., distally relative to the central portion 712, FIGS. 4A-4E), with the differential extension of the petals 720a-720c of the implant distal protection portion 700 shown directed proximally relative to the implant 200. Thus, petal 720c extends further proximally toward the implant 200 than either of the other petals 720b-720a, and petal 720b extends further proximally than petal 720a.

[0056]

[0065] The implant 200 is coaxially disposed around a core wire 350 (not shown) and held in a radially constrained delivery configuration by a tubular loading member 390, with the distal end 240 of the implant 200 being partially exposed from a distal end opening of the loading member 390.

[0057]

[0066] The distal end of the delivery wire assembly 300 including the implant distal protection portion 700 and the compressed implant 200 is advanced into the delivery catheter 120, and / or the delivery catheter 120 is advanced over the distal portion of the delivery wire assembly 300, thereby radially compressing the petals 720a-720c of the implant distal protection portion 700 above and over the distal portion 240 of the implant 200, as shown in Figures 9B-9C. Additionally or alternatively, radial compression of the implant distal protection portion 700 720a-720c above and over the distal portion 240 of the implant 200 may be assisted by compressing the petals in sequence, such as first compressing petal 720c, then compressing petal 720b, and finally compressing petal 720a. The radially compressed petals 720a-720c are disposed on and / or partially cover the distal portion 240 of the implant 200. In one embodiment, the stems 715a-715c are not disposed on and do not cover the distal portion 240 of the implant 200, as shown in Figures 9A-9B and 10A-10D.

[0058]

[0067] Once the delivery catheter 120 is positioned over each implant distal protection portion 700 and loading member 390, the loading member 390 is withdrawn while the implant 200 remains in a compressed delivery configuration within the lumen 125 of the delivery catheter 120, and the petals 720a-720c of the implant distal protection portion 700 remain compressed against and at least partially cover the distal portion 240 of the implant 200 (FIG. 9D).

[0059]

[0068] Although the disclosed invention is not so limited, the illustrated "three petal" configuration (e.g., stem and petals) of the implant distal protection portions 700-1100 is configured to minimize the amount of material covering the distal end of the distal portion 240 of the implant 200, thereby reducing and minimizing the drag or frictional forces exerted by the implant on the inner wall of the delivery catheter 120 as the implant 200 is pushed through the lumen 125. In particular, the inventors of the disclosed invention have discovered that by employing the illustrated configuration of the implant distal protection portions 700-1100, when there is relative movement between the core wire 350 and the delivery catheter 120, the coefficient of friction between the implant 200 and the inner wall of the delivery catheter 120 is in the range of about 0.01 to about 0.04.

[0060]

[0069] In various embodiments, the implant distal protection portion 700-1100 is sized and configured to cover different amounts of the distal end 240 of the implant 200 when the distal portion of the delivery wire assembly 300, including the implant 200 and the implant distal protection portion 700-1100, is constrained within the delivery catheter lumen 125. By way of non-limiting example, in one embodiment, the implant distal protection portion 700-1100 is sized and configured to cover about 20% of the total length of the implant 200 when the distal portion of the delivery wire assembly 300, including the implant 200 and the implant distal protection portion 700-1100, is constrained within the delivery catheter lumen 125. In another embodiment, the implant distal protection portion 700-1100 is sized and configured to cover about 10% to about 20% of the total length of the implant 200 when the distal portion of the delivery wire assembly 300, including the implant 200 and the implant distal protection portion 700-1100, is constrained within the delivery catheter lumen 125. In yet another embodiment, the implant distal protection portion 700-1100 is sized and configured to cover about 5% to about 10% of the total length of the implant 200 when the distal portion of the delivery wire assembly 300, including the implant 200 and the implant distal protection portion 700-1100, is constrained within the delivery catheter lumen 125. In yet another embodiment, the implant distal protection portion 700-1100 is sized and configured to cover about 5% or less of the total length of the implant 200 when the distal portion of the delivery wire assembly 300, including the implant 200 and the implant distal protection portion 700-1100, is constrained within the delivery catheter lumen 125.

[0061]

[0070] Figures 10A-10H show an implant distal protection portion 700 for delivering and deploying the implant 200 to / at a target site within a blood vessel (not shown). The implant distal protection portion 700 of Figures 4A-4E is shown in Figures 10A-10E as an exemplary distal protection portion used to deliver and deploy the implant 200. It should be understood that any of the implant distal protection portions disclosed in the alternative embodiments of Figures 5A-8 may be used to deliver and deploy the implant 200 to / at the target site.

[0062]

[0071] 10A shows the distal end of the delivery wire assembly 300 as the core wire 350 (not shown in FIG. 10A ) is pushed through the delivery catheter lumen 125. The implant 200 and peripheral implant protector 700 are shown in a compressed delivery configuration constrained within the delivery catheter lumen 125, with the petals 720a-720c of the implant distal protector 700 covering and protecting the distal portion 240 of the implant 200.

[0063]

[0072] Once the distal end of the delivery assembly 300 is positioned proximate to the target implantation site, the delivery catheter 120 is withdrawn proximally relative to the core wire 350 (indicated by arrow I), or the core wire 350 is pushed distally relative to the delivery catheter 120 (indicated by arrow II), or some portion of each, thereby exposing the implant distal protection portion 700 and the implant 200 from the distal end opening 452 of the delivery catheter 120, allowing the radially unconstrained implant 200 to self-expand radially starting from the distal end 240 to an expanded configuration, as shown in Figures 10B-10E.

[0064]

[0073] Because the petals 720a-720c of the implant distal protection portion 700 have different extension lengths (e.g., petal 720a is shorter than any of petals 720b-720c, petal 720b is shorter than petal 720c but longer than petal 720c, and petal 720c is longer than any of petals 720a-720b), the implant distal protection portion 700 is configured to allow each of the petals 720a-720c to be deployed sequentially as they exit the distal end opening 452 of the delivery catheter 120, thereby avoiding or minimizing the risk of entanglement of the petals 720a-720c and / or avoiding or minimizing potential damage to the implant distal protection portion 700 (e.g., inability to radially expand). The sequential exit from the delivery catheter 120 and radial expansion of the petals 720a-720c occurs in the following order: i) first, petal 720a (FIG. 10B), as the shortest of the petals, followed by ii) petal 720b (FIG. 10C), as the medium sized petal, and finally, iii) petal 720c (FIG. 10D), the longest of the petals, exits the distal end opening 452 of the delivery catheter 120. In particular, the petals 720a-720c remain extended proximally (i.e., in the "delivery configuration") when the distal end 240 of the implant 200 assumes the expanded configuration and is no longer covered by the implant distal protection portion 700, as shown in FIGS. 10D-10H.

[0065]

[0074] Additionally, each stem 715a-715c of the implant distal protection portion 700 is constructed from Nitinol or any suitable superelastic material such that the stems 715a-715c are configured to aid and further enable radial expansion of their respective petals 720a-720c by elastic energy during deployment of the implant 200 and ejection of the distal end 240 of the implant, while in the delivery configuration the petals 720a-720c remain extended in a proximal direction (e.g., toward the implant 200) (FIGS. 10A-10H). This feature further facilitates and enables recapture of the implant distal protection portion 700 upon retraction back into the delivery catheter 120 after the implant 200 has been deployed to / at the target site (not shown).

[0066]

[0075] The implant distal protection portion 700 is configured to exert a negligible or insignificant force on the distal portion 240 of the implant 200 as the implant 200 expands. In some embodiments, the implant distal protection portion 700 may expand radially outward when no longer radially constrained by the delivery catheter 120. In the described embodiment, when the implant distal protection portion 700 retains the delivery configuration or expands outward when no longer constrained by the delivery catheter 120, the petals 720a-720c are configured to extend and / or face proximally (i.e., oriented toward the delivery system or implant, and the individual petals 720a-720c preferably do not invert as the implant 200 expands).

[0067]

[0076] After deploying the implant 200 at the target site, the delivery wire assembly 300 is retracted back into the delivery catheter (not shown) and the delivery system 100 is withdrawn from within the body, leaving the expanded implant 200 embedded at the target site. In particular, as shown in FIGS. 10G-10H, the "proximal-facing" configuration of the implant distal protection portion 700 and its relatively small size relative to the expanded implant 200 allow the core wire 350 and distal implant protection portion 700 to be withdrawn through the lumen 260 of the implant 200 and back into the delivery catheter lumen 125 without interfering with the deployed and expanded implant 200. FIG. 10H is an expanded view of the cross section shown in FIG. 10G to better illustrate that the implant distal protection portion 700 substantially retains its delivery configuration even when the delivery catheter 120 no longer constrains it.

[0068]

[0077] The implant distal protection 700 may be fixedly attached to the core wire 350 by the locking member 750 such that the implant distal protection does not rotate relative to the core wire 350. Alternatively, the implant distal protection 700 may be rotatable relative to the core wire 350 and the locking member 750. The rotatable implant distal protection 700 is configured to allow torque transfer to the distal end of the core wire 350 (e.g., the atraumatic distal tip 380), thereby allowing for vessel selection and facilitating guidance of the delivery wire assembly 300 to the target implantation site. When the implant distal protection 700 rotates relative to the core wire 350, externally induced (e.g., by the patient's anatomy, user, clinician) relative twisting between the delivery catheter 120 and the core wire 350 is avoided or significantly reduced, preventing the accumulation of twisting energy that may adversely affect the deployment of the implant 200. Thus, the rotatable implant distal protector 700 is configured to prevent torsional energy from building up in the delivery wire assembly 300 and implant 200 when the assembly 300 and implant 200 are radially constrained within the lumen 125 of the delivery catheter 120. Additionally, the rotatable implant distal protector 700 is configured to allow the petals 720a-720c to be coupled (e.g., maintain contact) with the implant 200 in the delivery configuration when the core wire 350 experiences a twist.

[0069]

[0078] It should be understood that any of the features disclosed for implant distal protection portion 700 in particular in Figures 9A-10H are also disclosed for the alternative embodiments of Figures 5A-8, unless expressly different as described above.

[0070]

[0079] While specific embodiments have been shown and described herein, it will be understood by those skilled in the art that they are not intended to limit the invention of the present disclosure, and it will be apparent to those skilled in the art that various changes, substitutions and modifications (e.g., various part dimensions, combinations of parts) can be made without departing from the scope of the invention of the present disclosure, which is defined only by the following claims and their equivalents. Accordingly, the specification and drawings are to be regarded in an illustrative sense and not in a restrictive sense, and the embodiments shown and described herein are intended to cover such alternatives, modifications and equivalents as may be included within the scope of the appended claims.

Claims

1. 1. A delivery system for deploying an implant at a target site within a vessel of a mammal, the implant having a compressed delivery configuration and an expanded deployed configuration, the delivery system comprising: a delivery catheter having an internal lumen; an elongate delivery wire assembly at least partially disposed within a lumen of the delivery catheter, the delivery wire assembly being translatable relative to the delivery catheter and having an implant loading region configured to secure the implant when a distal portion of the delivery wire assembly containing the implant is constrained within the lumen of the delivery catheter such that the implant is in the compressed delivery configuration; an implant distal protector comprising a central portion coupled to the delivery wire assembly distal to the implant loading region and a peripheral portion extending proximally from the central portion to at least partially cover a distal end of the implant when the distal portion of the delivery wire assembly including the implant and the implant distal protector is constrained within a lumen of the delivery catheter; the peripheral portion of the implant distal protection portion is configured to expand when the peripheral portion of the implant distal protection portion is no longer constrained by the delivery catheter; A delivery system wherein the peripheral portion of the implant distal protection portion is configured not to invert from a proximal-facing direction to a distal-facing direction, such that when the implant assumes the expanded, deployed configuration after being released from the lumen of the delivery catheter and no longer covered by the peripheral portion of the implant distal protection portion, the peripheral portion of the implant distal protection portion remains extending in the proximal-facing direction, and the peripheral portion of the implant distal protection portion comprises a plurality of circumferentially spaced, elongated stems, each comprising a respective petal-shaped member, the plurality of stems extending from the central portion.

2. The delivery system of claim 1 , wherein each petal is disposed on and / or covers each of the elongated stems of the peripheral portion of the implant distal protection portion.

3. 3. The delivery system of claim 2, wherein each of the petals comprises: a first petal disposed at or covering about 80% to about 90% of the total length of the respective elongate stem; a second petal disposed at or covering about 60% to about 50% of the total length of the respective elongate stem; and a third petal disposed at or covering about 40% to about 30% of the total length of the respective elongate stem.

4. 4. The delivery system of claim 3, wherein the implant distal protection portion is configured to expand sequentially from the compressed delivery configuration to the expanded deployment configuration, with the first petal expanding, followed by the second petal expanding, and then the third petal expanding.

5. The delivery system of any one of claims 1 to 4, wherein the petals are substantially evenly circumferentially spaced around the delivery wire assembly.

6. A delivery system according to any preceding claim, wherein the petals comprise arcuate annular strips or concave formations.

7. The delivery system of any one of claims 1 to 4, wherein the central portion of the implant distal protection portion is fixedly attached to the delivery wire assembly in such a manner that the implant distal protection portion is fixed to the delivery wire assembly.

8. The delivery system of any one of claims 1 to 4, wherein the central portion of the implant distal protection portion is attached to the delivery wire assembly in such a way that the implant distal protection portion is rotatable relative to the delivery wire assembly.

9. 5. The delivery system of claim 1, wherein the implant distal protection portion covers approximately 20% of the total length of the implant when the distal portion of the delivery wire assembly including the implant and the implant distal protection portion is constrained within the lumen of the delivery catheter.

10. 5. The delivery system of claim 1, wherein the implant distal protection portion covers about 10% to about 20% of the total length of the implant when the distal portion of the delivery wire assembly including the implant and the implant distal protection portion is constrained within the lumen of the delivery catheter.

11. 5. The delivery system of claim 1, wherein the implant distal protection portion covers about 5% to about 10% of the total length of the implant when the distal portion of the delivery wire assembly including the implant and the implant distal protection portion is constrained within the lumen of the delivery catheter.

12. 5. The delivery system of claim 1, wherein the implant distal protection portion covers less than about 5% of the total length of the implant when the distal portion of the delivery wire assembly, including the implant and the implant distal protection portion, is constrained within the lumen of the delivery catheter.

13. 5. The delivery system of claim 1, wherein the implant distal protection portion is configured to exert negligible or insignificant force on the distal portion of the implant as the implant expands from the compressed delivery configuration to the expanded deployed configuration.

14. 5. The delivery system of claim 1, wherein the implant distal protection portion substantially retains its compressed delivery configuration after the implant distal protection portion radially expands and is no longer constrained by the delivery catheter.

15. The delivery system of any one of claims 1 to 4, wherein the implant distal protection portion is configured to prevent inversion in the distal-facing direction when the implant is expanded.

16. 16. The delivery system of claim 15, wherein the implant distal protection portion is configured to be pulled back into the delivery catheter without reversing from the proximal-facing direction to the distal-facing direction.

17. 3. The delivery system of claim 2, wherein each of the petals comprises a first petal positioned at or covering about 60% to about 90% of the total length of the respective elongate stem, and a second petal positioned at or covering about 50% to about 30% of the total length of the respective elongate stem.

18. 18. The delivery system of claim 17, wherein the implant distal protection portion is configured to expand sequentially from the compressed delivery configuration to the expanded deployment configuration, with the first petal expanding followed by the second petal expanding.

19. 4. The delivery system of claim 3, wherein each said petal comprises three or more petals, each covering a different proportion of the length of their corresponding elongate stem.

20. 20. The delivery system of claim 19, wherein the implant distal protection portion is configured to expand sequentially from the compressed delivery configuration to the expanded deployed configuration, and the plurality of petals causes the petals to expand sequentially.

Images