Patent Description:
Medical devices such as coils, tubular mesh elements and other expandable members, collectively referred to hereinafter as "embolic devices," are often utilized for treating various types of vascular defects, particularly, aneurysms. Aneurysms are localized, blood-filled dilation of a blood vessel caused by disease, blood flow/pressure exerted in the vessel and/or weakening of the vessel wall. Aneurysm usually assumes a sac or balloon-like configuration that extends from a blood vessel. Aneurysm can rupture and cause hemorrhage, stroke (e.g., intracranial aneurysm) and other damaging consequences to the patient. During the treatment of an aneurysm, an embolic device is loaded onto a delivery system in a collapsed or radially compressed delivery configuration and then introduced into an aneurysm sac. Once delivered within the aneurysm sac, the embolic device may then expand or be expanded to an expanded configuration filling and occluding the aneurysm. Embolic devices may have a variety of sizes and shapes; however, embolic devices for treatment of aneurysm usually assume a spherical secondary configuration when deployed within the aneurysm sac. When implanted within the sac, the embolic device may further reinforce the inner walls of the aneurysm sac while occluding the aneurysm, reducing the probability of rupture or preventing further rupture of the aneurysm.

Embolic devices are commonly composed of self-expanding materials, so that when the devices are deployed from the delivery system into the target location in a patient; the unconstrained devices expand without requiring assistance. Self-expanding embolic devices may be biased so as to expand upon release from the delivery catheter and/or include a shape-memory component which allows the device to expand upon exposure to a predetermined condition. Some embolic devices may be characterized as hybrid devices which have some characteristics of both self-expandable materials and non-self-expandable materials.

Embolic devices can be made from a variety of materials, including polymers (e.g., nonbioerodable and bioerodable plastics) and metals. Bioerodable polymer embolic devices are desirable for some applications due to their biodegradeability and generally increased flexibility compared to metal embolic devices. Embolic devices can be made from shape memory or superelastic materials, such as shape memory metals (e.g., shape memory Nitinol) and polymers (e.g., polyurethane). Such shape memory embolic devices can be induced (e.g., by temperature, electrical or magnetic field or light) to take on a shape (e.g., a radially expanded shape) after delivery to a treatment site. Superelastic embolic materials, such as superelastic Nitinol, take on a shape after delivery without need for an inductive stimulus. Other devices materials include stainless steel, platinum, and Elgiloy. In drug delivery embolic devices, the device can carry and/or the surface of the device can be coated with a bioactive or therapeutic agent (e.g., thrombosis inducing agent).

Commonly used embolic devices are helical wire coil having windings dimensioned to engage the walls of the aneurysm. Although, embolic coils may migrate out of an aneurysm sac, particularly when delivered in wide neck aneurysm.

Some exemplary embolic coils are described, for instance, in <CIT>, which discloses an embolic coil that assumes a linear helical configuration when stretched and a folded, convoluted configuration when relaxed. The stretched configuration is used in placing the coil at the target site (by its passage through a delivery catheter) and the coil assumes a convoluted relaxed configuration once the device is deployed at the target site. The '<NUM> patent discloses a variety of secondary shapes of the embolic coils when deployed at the target site, such as "flower" shapes, double vortices, and random convoluted shapes. Other three-dimensional embolic coils have been described in <CIT> (i.e., three-dimensional in-filling embolic coil),<CIT> (i.e., embolic coils having twisted helical shapes) and<CIT>(i.e., variable cross-section conical embolic coils). Embolic coils having little or no inherent secondary shape have also been described, such as in <CIT> and <CIT>.

Spherical shaped embolic devices are described in <CIT>, which discloses that one or more strands can be wound to form a substantially hollow spherical or ovoid shape comprising overlapping strands when deployed in an aneurysm. Other embolic devices that assume spherical shapes when deployed are described in <CIT>, which discloses tubular mesh having petal-like sections to form a substantially spherical shape having overlapping petals-like sections when deployed in an aneurysm.

<CIT> describes an implant having a coil for embolizing a vascular site, such as aneurysm. The coil has a specific three-dimensional shape that is achieved by winding the coil around a mandrel in a specific pattern and then heat setting the coil and the mandrel. The three-dimensional shape resembles unclosed mobius loops.

A variety of delivery assemblies for embolic devices are known. For instance, <CIT> (i.e., interlocking clasps), <CIT> (i.e., interconnecting guidewire to deliver multiple coils), and <CIT> and <CIT>, to Guglielmi (i.e., electrolytic detachment).

The invention pertains to an embolic device according to claim <NUM>. In an exemplary embodiment of the disclosed inventions, an embolic device is formed out of an elongate flat member having a longitudinal axis, a first side comprising a first side surface, and a second side comprising a second side surface, the first and second sides being reverse to each other with the first side surface and second side surface facing in opposite directions. The elongate flat member has an elongated constrained configuration for being deployed through a delivery catheter to targeted vascular site, and a three-dimensional unconstrained configuration, wherein in the three-dimensional unconstrained configuration, the elongate flat member assumes a plurality of successive loops in which the elongate flat member is at least partially twisted about its longitudinal axis between each loop of the plurality, so that the first side surface faces externally of each loop, and the second side surface faces an interior of each loop, respectively, regardless of a change in direction and/or orientation of the elongate flat member.

Without limitation, the elongate flat member may be a braid formed out of one or more braid members, wherein the one or more braid members are metallic filaments or wires. For example, the elongate flat member may be a flattened tubular braid or a single layer, flat ribbon braid.

In an exemplary embodiment, the three-dimensional unconstrained configuration is imparted on the elongate flat member by thermally treating the elongate flat member while the elongate flat member is wound in alternating directions about respective posts extending outwardly from a mandrel to thereby form the plurality of successive loops. In a preferred embodiment, the plurality of successive loops include at least a first loop defining a first plane, a second loop defining a second plane that is not coplanar with the first plane, and a third loop defining a third plane that is not coplanar with either of the first and second planes. In one exemplary embodiment, the plurality of successive loops comprising at least five successive loops.

In a more particular exemplary embodiment, an embolic device is provided for occluding an aneurysm, the embolic device comprising an elongate flat braid formed out of one or more metallic braid filaments or wires and having a longitudinal axis, a first side comprising a first side surface, and a second side comprising a second side surface, the first and second sides being reverse to each other with the first side surface and second side surface facing in opposite directions. The elongate flat braid has an elongated constrained configuration for being deployed through a delivery catheter into the aneurysm, and a three-dimensional unconstrained configuration after being deployed out of the delivery catheter within the aneurysm, wherein in the three-dimensional unconstrained configuration, the elongate flat braid assumes a plurality of successive loops in which the elongate flat braid is at least partially twisted about its longitudinal axis between each loop of the plurality, so that the first side surface faces externally of each loop towards an interior wall of the aneurysm, and the second side surface faces an interior of each loop, respectively, regardless of a change in direction and/or orientation of the elongate flat braid.

By way of example, the elongate flat braid may be a flattened tubular braid, or a single layer, flat ribbon braid, wherein the three-dimensional unconstrained configuration is imparted on the elongate flat braid by thermally treating the elongate flat braid while the elongate flat braid is wound in alternating directions about respective posts extending outwardly from a mandrel to thereby form the plurality of successive loops. The plurality of successive loops preferably include at least three successive loops, including a first loop defining a first plane, a second loop defining a second plane that is not coplanar with the first plane, and a third loop defining a third plane that is not coplanar with either of the first and second planes. In one embodiment, the plurality of successive loops includes at least five successive loops.

Other and further aspects and features of embodiments will become apparent from the ensuing detailed description in view of the accompanying figures.

The term "about" generally refers to a range of numbers that one of skilled in the art would consider equivalent to the recited value (i.e., having the same function or result).

The figures are not necessarily drawn to scale, the relative scale of select elements may have been exaggerated for clarity, and elements of similar structures or functions are represented by like reference numerals throughout the figures. It should also be understood that the figures are only intended to facilitate the description of the embodiments, and are not intended as an exhaustive description of the invention or as a limitation on the scope of the invention, which is defined only by the appended claims and their equivalents. An aspect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiments even if not so illustrated.

<FIG> illustrates an embolic device <NUM>, according to the embodiments of the disclosed inventions. The embolic device <NUM> comprises an elongated constrained configuration (<FIG>) for being deployed through a delivery catheter <NUM> to targeted vascular site <NUM> (e.g., aneurysm sac). The embolic device <NUM> further comprises a three-dimensional unconstrained configuration (<FIG> and <FIG>), in which the device <NUM> assumes a plurality of successive loops <NUM>. For example, the device three-dimensional unconstrained configuration is assumed after the device <NUM> is advanced out of a distal opening <NUM> of the delivery catheter <NUM>, and/or the delivery catheter <NUM> is withdrawn proximally relative to the embolic device <NUM> (or some of each) into the targeted vascular site <NUM> (<FIG>). The three-dimensional unconstrained configuration is set by applying a series of manufacturing steps to an elongate flat member <NUM> to include successive loops <NUM> in which the elongate flat member <NUM> is at least partially twisted about its longitudinal axis between each loop of the plurality, so that a first side surface <NUM> faces externally of each loop <NUM> towards an interior wall <NUM> of the aneurysm <NUM>, and a second side surface <NUM> faces an interior <NUM> of each loop <NUM>, respectively, regardless of a change in direction and/or orientation of the elongate flat member <NUM> (<FIG>, <FIG>). The plurality of successive loops <NUM> may include a first loop defining a first plane, a second loop defining a second plane that is not coplanar with the first plane, and a third loop defining a third plane that is not coplanar with either of the first and second planes, as shown in <FIG> and <FIG>. In some embodiments, the plurality of successive loops comprises at least five successive loops <NUM>, as shown in <FIG>.

The application of the series of manufacturing steps to the elongate flat member <NUM> for setting the three-dimensional unconstrained configuration of the embolic device <NUM> will be described in further detail below.

The elongate flat member <NUM> forming the embolic device <NUM> has a proximal portion <NUM>, a middle portion <NUM> and distal portion <NUM>, as shown in <FIG>. The proximal portion <NUM> includes a proximal end <NUM>, and the distal portion <NUM> includes a distal end <NUM>. The elongate flat member <NUM> comprises a ribbon-like configuration having a rectangular cross-section, as shown in <FIG>. Alternative, the elongate flat member <NUM> may have any other suitable cross-sections, as for example: an ovoid or elliptical (<FIG>), flattened with rounded edges (<FIG>), flattened tubular (<FIG>) cross-section or the like, or combinations thereof. The elongate flat member <NUM> further comprises a longitudinal axis <NUM>, a first side <NUM> comprising a first side surface <NUM>, and a second side <NUM> comprising a second side surface <NUM>, the first and second sides <NUM> and <NUM> being reverse to each other with the first side surface <NUM> and second side surface <NUM> facing in opposite directions, as shown in <FIG>.

For ease in illustration, the elongate flat member <NUM> shown in <FIG> is composed of a single layer <NUM> of material having the ribbon-like configuration. The single layer <NUM> of material may be a porous and/or permeable, as for example, a layer <NUM> formed of a plurality of braided wires <NUM> or weaved filaments <NUM>' (<FIG>), a mesh <NUM> (<FIG>), and/or a layer <NUM> of material having perforations <NUM> (<FIG>), or the like or combinations thereof. The wires <NUM> and/or filaments <NUM>' are composed of biocompatible metallic and/or polymeric materials, alloys or combinations thereof. For example, one or more wires <NUM> may have a platinum core with a respective outer layer of Nitinol. In some embodiments, the elongate flat member <NUM> comprises a single layer, flat ribbon braid. When the elongate flat member <NUM> is braided, woven or mesh, the proximal end <NUM> and/or distal end <NUM> may be secured, having the plurality of wires <NUM> attached or coupled to each other, or to another element (e.g., a cap, non-traumatic tip, or the like) at the respective proximal end <NUM> and/or distal end <NUM> via adhesive, clamping, or the like, as shown at the distal end <NUM> in <FIG>. Alternatively, the proximal end <NUM> and/or distal end <NUM> of the elongate flat member <NUM> may be unsecured, having the plurality of wires <NUM> at the respective proximal end <NUM> and/or distal end <NUM> lose and free, as shown at the distal end <NUM> in <FIG>. Further, a coil <NUM> may be coupled to the secured proximal end <NUM> and/or distal end <NUM> the elongate flat member <NUM>, as shown at the distal end <NUM> in <FIG>. The coil <NUM> may be composed of shape memory material and may assume a loop like configuration, such as the loops <NUM> of the embolic device <NUM>, when the embolic device <NUM> is in the three-dimensional unconstrained configuration. The coil <NUM> when disposed at the distal end <NUM> of the elongate flat member <NUM> may be configured to lead the embolic device when deployed within an aneurysm <NUM>.

In some embodiments, the elongate flat member <NUM> comprises a braid that is formed out of one or more braid members, and the one or more braid members are metallic filaments or wires.

In further embodiments, the single layer <NUM> of material may be a non-porous or impermeable layer of material (e.g., solid), as shown in <FIG>. It should be appreciated that the single layer <NUM> of the elongate flat member <NUM> may include one or more materials, alloys of combinations thereof.

In other embodiments, the elongate flat member <NUM> may be composed of a plurality of layers <NUM> (e.g., <FIG>); the layers may be porous/permeable, non-porous/impermeable and/or include one or more materials, as described above, or combinations thereof. The elongate flat member <NUM> composed of a plurality of layers <NUM> may have the flat-ribbon configuration of <FIG>. By way of non-limiting example, the elongate flat member <NUM> may include a tubular member <NUM>, as shown in <FIG>, the tubular member <NUM> may include a braid or mesh that is flattened forming a similar flat-ribbon configuration of <FIG>, such as a flattened tubular braid, as shown in <FIG>. The tubular member <NUM> when flattened into the ribbon-like configuration includes at least two layers <NUM>, as shown in <FIG>. In another exemplary embodiment, the elongate flat member <NUM> may be composed of a cylindrical member <NUM>, as shown in <FIG>, that is flattened forming a similar flat-ribbon configuration of <FIG>, as shown in <FIG>. The cylindrical member <NUM> may be composed of one or more materials or combinations thereof. The cylindrical element <NUM> of <FIG> may further include a core <NUM> and an outer layer <NUM>. By way of non-limiting example, the core <NUM> may be composed of platinum and the outer layer <NUM> may be composed of Nitinol.

It should be appreciated that the elongate flat member <NUM> can be woven from wires, cut out of tubes, or cut out of sheets using a variety of techniques, including laser cutting or etching a pattern onto a tube or sheet, or other suitable techniques. It should be further appreciated that other suitable configurations of the elongate flat member <NUM> may be considered for the manufacturing of the embolic device <NUM>.

Referring back to <FIG>, the elongate flat member <NUM> comprises a length L<NUM> that ranges from approximately <NUM> to <NUM> centimeters, and in some embodiments the L<NUM> ranges from approximately <NUM> to <NUM> centimeters. The elongate flat member <NUM> further comprises a width W<NUM> that ranges from approximately <NUM> to <NUM> millimeters, and in some embodiments the W<NUM> ranges from approximately <NUM> to <NUM> millimeters. Additionally, the elongate flat member <NUM> comprises a thickness T<NUM> that ranges from approximately <NUM> to <NUM> millimeters, and in some embodiments the T<NUM> ranges from approximately <NUM> to <NUM> millimeters. In some embodiments, the one or more dimension (L<NUM>, W<NUM>, or T<NUM>) of the elongate flat member <NUM> remain constant throughout the element <NUM>, such as having the same dimension from the proximal portion <NUM> to the distal portion <NUM>. In other embodiments, the one or more dimension (L<NUM>, W<NUM>, or T<NUM>) of the elongate flat member <NUM> may varied, having different dimension along the length of the elongate flat member <NUM> (e.g., tapered configuration).

The elongate flat member <NUM> may be composed from any number of biocompatible, compressible, elastic materials or combinations thereof, including polymeric materials, metals, and metal alloys, such as stainless steel, tantalum, or a nickel titanium alloy such as a super-elastic nickel titanium alloy known as Nitinol. Certain super-elastic alloys may be desirable for their shape recoverable features, which tolerate significant flexing without deformation even when used in small dimensioned elongate flat member <NUM>. Further when the embolic device <NUM> comprises an elongate flat member <NUM> composed of self-expanding materials, the unconstrained embolic device <NUM> is biased to expand into the predetermined deployed configuration, which will be described in further detail below. Some super-elastic alloys include nickel/titanium alloys (<NUM>-<NUM> atomic % nickel and optionally containing modest amounts of iron); copper/zinc alloys (<NUM>-<NUM> weight % zinc); copper/zinc alloys containing <NUM>-<NUM> weight % of beryllium, silicon, tin, aluminum, or gallium; or nickel/aluminum alloys (<NUM>-<NUM> atomic % aluminum).

The elongate flat member <NUM> may include radio-opaque markers or be coated with a layer of radiopaque materials. Additionally, the elongate flat member <NUM> may carry and/or the surfaces of the elongate flat member <NUM> may be coated with a bioactive or therapeutic agent (e.g., thrombosis inducing agent).

Further suitable metals and alloys for the elongate flat member <NUM> include the Platinum Group metals, such as, platinum, rhodium, palladium, rhenium, as well as tungsten, gold, silver, tantalum, and alloys of these metals, such as platinum/tungsten alloy, or the like and combinations thereof. These metals have significant radiopacity and in their alloys may be tailored to accomplish an appropriate blend of flexibility and stiffness.

<FIG> illustrate the embolic device <NUM> of <FIG> comprising the elongate flat member <NUM> and being manufactured using a mandrel <NUM>. The elongate flat member <NUM> is disposed on a mandrel <NUM>. The mandrel <NUM> comprises a handle post <NUM> extending from a proximal portion <NUM> to a distal portion <NUM>. The distal portion <NUM> of the mandrel <NUM> comprises a plurality of extending posts <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM>. The handle post <NUM> and the laterally extending posts <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM>, comprise cylindrical or tubular configurations having rounded cross-sections. Alternative, the handle post <NUM> and the laterally extending posts <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM>, may comprise any other suitable configuration, such as, for example having elliptical cross-sections. The extending posts <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> extends outward from the handle post <NUM> distal portion <NUM>, and are circumferentially disposed around the handle post <NUM> distal portion <NUM>. Each of the extending post <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> comprises a respective center point (e.g., <NUM>'), in which each extending post is disposed at a suitable degree (e.g., approximately between <NUM> to <NUM> degrees) relative to the adjacent post center point, as shown in <FIG>. In alternative embodiments, the mandrel <NUM> may comprise four extending posts, in which each extending post is disposed at approximately <NUM> degrees relative to the adjacent post center point (not shown). It should be appreciated that the mandrel <NUM> may comprise any number of extending posts, any number of angles between the extending post (e.g., the posts may be symmetrically or not-symetrically disposed between each other), or any other suitable configuration for the manufacturing of the embolic device <NUM>, such as for example the mandrel <NUM>' of <FIG>. The mandrel <NUM>' of <FIG> includes a flat base <NUM> and a plurality of extending posts <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> extending outwardly from the base <NUM>.

The elongate flat member <NUM> is disposed on the mandrel <NUM> by laying the elongate flat member <NUM>, particularly one of either, the first side surface <NUM> or the second side surface <NUM> against the mandrel <NUM>. For example, when the first side surface <NUM> of the elongate flat member <NUM> is laid against, disposed on, or in contact with the mandrel <NUM>, the second side surface <NUM> is exposed and visible to the technician manufacturing the embolic device <NUM> (i.e., not contacting the mandrel <NUM>), not shown. Conversely, when the second side surface <NUM> of the elongate flat member <NUM> is laid against, disposed on or in contact with the mandrel <NUM>, the first side surface <NUM> of the elongate flat member <NUM> is exposed and visible to the technician manufacturing the embolic device <NUM> (i.e., not contacting the mandrel <NUM>) as shown in <FIG>.

In the three-dimensional unconstrained configuration of the embolic device <NUM>, the elongate flat member <NUM> assumes a plurality of successive loops <NUM> in which the elongate flat member <NUM> is at least partially twisted about its longitudinal axis between each loop of the plurality, so that the first side surface <NUM> faces externally of each loop <NUM>, and the second side surface <NUM> faces an interior of each loop <NUM>, respectively, regardless of a change in direction and/or orientation of the elongate flat member <NUM>. The three-dimensional unconstrained configuration of the embolic device <NUM> is set by disposing and wrapping the elongate flat member <NUM> in the mandrel (e.g., <FIG>) forming a plurality of successive loops <NUM>, by at least partially twisting the elongate flat member <NUM> about its longitudinal axis between each post of the mandrel forming each loop of the plurality, so that the first side surface <NUM> faces externally of each post and/or loop, and the second side surface <NUM> faces an interior of each loop and is at least in partial contact with each post, respectively, regardless of a change in direction and/or orientation of the elongate flat member <NUM>, as shown in <FIG>.

The at least partial twist of the elongate flat member <NUM> about its longitudinal axis between each loop and/or between each post is depicted in detail in <FIG>. The partial twist is approximately <NUM>° about the longitudinal axis elongate flat member <NUM>, so that that the first side surface <NUM> of the elongate flat member <NUM> faces externally of each loop <NUM>, and the second side surface <NUM> elongate flat member <NUM> faces an interior of each loop, respectively, regardless of a change in direction and/or orientation of the elongate flat member <NUM> when the embolic device <NUM> is in the three-dimensional unconstrained configuration, as shown in <FIG> and <FIG>. It should be appreciated that the partial twist may include other suitable degrees about the longitudinal axis elongate flat member <NUM>, as long as, one of the side surface (e.g., first side surface <NUM>) of the elongate flat member <NUM> faces externally of each loop <NUM>, and the reversed side surface (e.g., second side surface <NUM>) of the elongate flat member <NUM> faces an interior <NUM> of each loop <NUM>, respectively, regardless of a change in direction and/or orientation of the elongate flat member <NUM> in the three-dimensional unconstrained configuration of the embolic device <NUM>.

Further, a degree of twist between successive loops <NUM> can be expressed as a pitch where there is an amount of twist angle per unit length. The twist pitch is preferably related to the diameter of the adjacent loops <NUM> wherein the pitch is about <NUM> to <NUM> times <NUM>° / π D, where D is the average curve diameter of the adjacent loops <NUM>. The twist pitch may vary from approximately <NUM> to approximately <NUM> times (<NUM>° / π D), and in some embodiments, the twist pitch may vary from approximately <NUM> to approximately <NUM> times (<NUM>° / π D). In one embodiment, the twists of the elongate flat member <NUM> forming the three-dimensional unconstrained configuration of the embolic device <NUM> generally occur with a constant cross-section of the elongate flat member <NUM> throughout the twists. Alternatively, the twists may occur where the cross-section of the elongate flat member <NUM> changes throughout the twist.

For illustration purposes, <FIG> depicts an undesirable partial twist of the elongate flat member <NUM> about its longitudinal axis (e.g., <NUM>°) between each loop and/or between each post, since this twist will cause first side surface <NUM> of the elongate flat member <NUM> to face externally and internally in alternating loops, and the second side surface <NUM> elongate flat member <NUM> to also face externally and internally in alternating loops.

The steps of disposing, laying, wrapping and/or twisting the elongate flat member <NUM> on the mandrel <NUM>, will be described in further detail below. After the elongate flat member <NUM> is disposed on the mandrel <NUM> forming the three-dimensional configuration of the embolic device <NUM>, the embolic device <NUM> is thermally treated while the elongate flat member <NUM> is wound in alternating directions about respective posts extending outwardly from the mandrel to thereby form the plurality of successive loop <NUM>. The three-dimensional unconstrained configuration of the embolic device <NUM> is imparted by thermally treating elongate flat member <NUM> as described above, so that the device <NUM> is biased to assume the three-dimensional unconstrained configuration, as shown in <FIG> and <FIG>. The mandrel <NUM> is composed of materials having sufficient heat resistance to allow the heat treatment of the embolic device <NUM>. The mandrel <NUM> usually comprises refractory material such as alumina or zirconia, or any other suitable heat resistant material.

<FIG> depicts a manufacturing method <NUM> of the embolic device <NUM> using the above described elongate flat member <NUM> and mandrel <NUM>.

In step <NUM>, either the proximal end <NUM> or the distal end <NUM> of the elongate flat member <NUM> is first disposed on the mandrel <NUM>, so that either the first surface <NUM> or the second surface <NUM> is in contact with the mandrel <NUM>. By way of non-limiting example, the proximal end <NUM> of the elongate flat member <NUM> is laid against the handle post <NUM> disposed proximately to the extending posts <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM>, having a portion of the second side surface <NUM> in contact with the mandrel <NUM>, as shown in <FIG>.

In step <NUM>, the elongate flat member <NUM> is partially twisted about its longitudinal axis and further disposed around a first extending post forming a loop so that the first side surface faces externally, (e.g., away from the post), and the second side surface faces internally (e.g., towards or in partial contact with the post). For example, the elongate flat member <NUM> is extended so as to partially twist and wrap around the first extending post <NUM> in a clockwise direction having a portion of the second side surface <NUM> in contact with the extending post <NUM>, as shown in <FIG>.

In step <NUM>, the elongate flat member <NUM> is partially twisted about its longitudinal axis and further disposed around a second extending post forming a loop so that the first side surface faces externally, (e.g., away from the post), and the second side surface faces internally (e.g., towards or in partial contact with the post). As shown in <FIG>, the elongate flat member <NUM> is extended so as to partially twist and wrap around the second extending post <NUM> in a counter-clockwise direction having a portion of the second side surface <NUM> in contact with the extending post <NUM>.

In step <NUM>, the elongate flat member <NUM> is partially twisted about its longitudinal axis and further disposed around a third extending post forming a loop so that the first side surface faces externally, (e.g., away from the post), and the second side surface faces internally (e.g., towards or in partial contact with the post). As shown in <FIG>, the elongate flat member <NUM> is extended so as to partially twist and wrap around the third extending post <NUM> in a clockwise direction having a portion of the second side surface <NUM> in contact with the third extending post <NUM>.

In step <NUM>, the elongate flat member <NUM> is partially twisted about its longitudinal axis and further disposed around a fourth extending post forming a loop so that the first side surface faces externally, (e.g., away from the post), and the second side surface faces internally (e.g., towards or in partial contact with the post). As shown in <FIG>, the elongate flat member <NUM> is extended so as to partially twist and wrap around the fourth extending post <NUM> in a counter-clockwise direction having a portion of the second side surface <NUM> in contact with the extending post <NUM>.

In step <NUM>, the elongate flat member <NUM> is partially twisted about its longitudinal axis and further disposed around a fifth extending post forming a loop so that the first side surface faces externally, (e.g., away from the post), and the second side surface faces internally (e.g., towards or in partial contact with the post). For example, the elongate flat member <NUM> is extended so as to partially twist and wrap around the fifth extending post <NUM> in a clockwise direction having a portion of the second side surface <NUM> in contact with the extending post <NUM>, as shown in <FIG>.

In step <NUM>, the elongate flat member <NUM> is partially twisted about its longitudinal axis and further disposed around a sixth extending post forming a loop so that the first side surface faces externally, (e.g., away from the post), and the second side surface faces internally (e.g., towards or in partial contact with the post). As shown in <FIG>, the elongate flat member <NUM> is extended so as to partially twist and wrap around the sixth extending post <NUM> in a counter-clockwise direction having a portion of the second side surface <NUM> in contact with the extending post <NUM>.

In step <NUM>, the elongate flat member <NUM> is heat treated providing the three-dimensional unconstrained configuration of the embolic device <NUM>, as shown in <FIG> and <FIG>.

In an optional step <NUM> prior to step <NUM>, the elongate flat member <NUM> may be further partially twisted and disposed around handle post and/or extending posts in alternating clockwise and counter-clockwise directions having a surface of the elongate flat member <NUM> in at least a partial contact with the extending posts and handle post.

It should be appreciated that in the steps <NUM> to <NUM>, the transitions of the elongate flat member <NUM> from one post to another post of the mandrel <NUM> are discrete, in a wave-like fashion, allowing one of the side surfaces (e.g., <NUM>) of the elongate flat member <NUM> to at least partially contact the mandrel <NUM> while the opposite side surface (e.g., <NUM>) is free, visible or exposed (i.e., not contacting the mandrel <NUM>).

The embolic device <NUM> resulting from the above described manufacturing steps comprises a three-dimensional unconstrained configuration having a plurality of successive loops in which the elongate flat member <NUM> is at least partially twisted about its longitudinal axis between each loop of the plurality, so that the first side surface <NUM> faces externally of each loop, and the second side surface <NUM> faces an interior of each loop, respectively, regardless of a change in direction and/or orientation of the elongate flat member, as shown in <FIG> and <FIG>. The side surface of the elongate flat member <NUM> that was disposed on the mandrel <NUM> during the manufacturing steps (e.g., surface <NUM>) faces the interior <NUM> of each loop <NUM> (e.g., concave portions), while the side surface of the elongate flat member <NUM> that was not contacting the mandrel <NUM> during the manufacturing steps (e.g., surface <NUM>) faces the exterior of each loop <NUM> (e.g., convex portion) of the embolic device <NUM> in the three-dimensional unconstrained configuration, as shown in <FIG> and <FIG>.

The features of the embolic device <NUM> three-dimensional unconstrained configuration provide several important advantages, for example for use as an embolic device intended for small-diameter site, such as a neurovascular aneurysm. First, the embolic device <NUM> can be forced into a highly compressed or contracted state with relatively little bending or stress since the embolic device <NUM> comprises discrete transition areas (e.g., loops, partial twists). This contrasts with embolic devices having sharp twists, bends or turns causing packing inefficient and inability to be compressed tightly due to its relatively rough transition areas. Similarly, the stress on embolic devices having sharp twists, bends or turns, overlapping sections may create more contact points and friction of the embolic device with the delivery system, particularly during movement through a tortuous vascular path, having undesirable effects (e.g., slower deployment of the embolic devices, embolic device metal fatigue, or the like).

Further, when the embolic device <NUM> is being deployed through a delivery catheter <NUM> into the aneurysm <NUM>, and assumes the three-dimensional unconstrained configuration after being deployed out of the delivery catheter <NUM> within the aneurysm (<FIG>), the elongate flat member <NUM> assumes a plurality of successive loops <NUM> in which the elongate flat member <NUM> is at least partially twisted about its longitudinal axis between each loop <NUM> of the plurality, so that the first side surface <NUM> faces externally of each loop <NUM> towards an interior wall <NUM> of the aneurysm <NUM>, and the second side surface <NUM> faces an interior <NUM> of each loop, respectively, regardless of a change in direction and/or orientation of the elongate flat member <NUM>, so that the first side surface <NUM> of the device <NUM> engages and contacts the interior wall <NUM> of the aneurysm <NUM> without distending the sac or having any sharp turns or angles that may cause damage or rupture of the aneurysm interior wall <NUM>.

It should be appreciated that the embolic device <NUM> constructed according to the disclosed inventions may be deployed into the target site by methods known in the art.

Although particular 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 present inventions, and it will be obvious to those skilled in the art that various changes, permutations, and modifications may be made (e.g., the dimensions of various parts, combinations of parts) without departing from the scope of the disclosed inventions, which is to be defined only by the following claims.

Claim 1:
An embolic device (<NUM>), comprising:
an elongate flat member (<NUM>) having a longitudinal axis, a first side (<NUM>) comprising a first side surface (<NUM>), and a second side (<NUM>) comprising a second side surface (<NUM>), the first and second sides being reverse to each other with the first side surface and second side surface facing in opposite directions,
the elongate flat member having an elongated constrained configuration for being deployed through a delivery catheter to targeted vascular site, and a three-dimensional unconstrained configuration, the elongate flat member composed of a metal selected from the group consisting of: a Platinum Group metal, rhenium, tungsten, gold, silver and tantalum, and an alloy of any of the foregoing metals,
wherein in the three-dimensional unconstrained configuration, the elongate flat member assumes a plurality of successive loops (<NUM>) in which the elongate flat member is at least partially twisted about its longitudinal axis between each loop (<NUM>) of the plurality,
characterized in that the first side surface (<NUM>) faces externally of each loop, and the second side surface (<NUM>) faces an interior of each loop, respectively, regardless of a change in direction and/or orientation of the elongate flat member, and wherein the plurality of successive loops includes a first loop defining a first plane, a second loop defining a second plane that is not coplanar with the first plane, and a third loop defining a third plane that is not coplanar with either of the first and second planes.