Vaso-occlusive devices comprising complex-shape proximal portion and smaller diameter distal portion

(Field of Invention) Assemblies and methods for repairing aneurysms are disclosed. In particular, vascular occlusion devices are disclosed as methods of making and using these devices.

(Background) An aneurysm is a dilation of a blood vessel that poses a health risk from the possibility of rupture, coagulation, or tearing. Rupture of an aneurysm in the brain causes a stroke, and an aneurysm in the abdomen causes shock. Cerebral aneurysms are usually detected as a result of seizures or bleeding in patients and can result in significant morbidity or mortality.

There are various materials and devices used for the treatment of aneurysms, including platinum and stainless steel microcoils, polyvinyl alcohol sponges (Ivalone), and other mechanical devices. A vaso-occlusive device either blocks the flow of blood through the blood vessels that make up that part of the vascular system by forming an embolus, or forms such an embolus within an aneurysm that arises from this blood vessel. Typically, a surgical instrument or embolus placed within the vascular system of the human body via a catheter. One widely used vascular occlusion device is a spiral wire coil with windings that can be sized to engage the walls of the blood vessel. Other less rigid spiral coil devices, and woven braids are described. For example, a vascular occlusion device either blocks the flow of blood through the blood vessels that make up that part of the vascular system by forming an embolus, or forms such an embolus within an aneurysm that arises from this blood vessel. A surgical instrument or embolus that is typically placed within the vascular system of the human body via a catheter.

For example, Patent Document 1 by Ritchart et al. Describes a vascular occlusion coil that takes a linear spiral morphology when stretched and a circumflex morphology folded when relaxed. This stretched state is used when placing the coil at the desired site (by its passage through the catheter), and the coil is better suited for occluding blood vessels when the device is so placed. It takes a relaxed form. Richart et al. Describe various "composite" three-dimensional shapes. The secondary shape of this disclosed coil includes a "flower" shape and a double swirl. Random shapes are described as well. Other less rigid spiral coil devices, as well as devices containing woven braids, are described. See, for example, Patent Document 2.

Other three-dimensional vascular occlusion devices are described. Patent Document 3 by Mariant describes an in-filling vascular occlusion coil. Patent Document 4 by Mariant et al. Describes an embolic coil having a twisted spiral shape, and Patent Document 5 by Wallace et al. Describes a variable cross-section conical vascular occlusion coil.

Patent Document 6 by Gianturco describes an occlusion bag of foldable material and a vascular occlusion assembly with a filling member, eg, a spiral coil with a J-hook on the proximal end. The bag is expanded to form a diamond-shaped structure, and the filling member inside the bag is pushed into a convoluted form as it advances into the cavity of the foldable bag.

Portable devices using coils of various shapes are shown in Patent Document 7 by Purdy. Purdy described a multi-element intravascular occlusion device in which a molded coil could be employed. Patent Document 8 by Neuss shows a spiral implant that can take a variety of secondary shapes. Several composite shapes can be formed by interconnecting two or more helical implants.

Vascular occlusion coils with little or no inherent secondary shape are also described. For example, Patent Documents 9 and 10 by Berenstein et al., Co-owned by the Applicant, describe coils that have little or no shape after introduction into a vascular space. ..

Various mechanically detachable devices are also known. For example, Patent Document 11 by Sepetka shows a method of removing a spirally wound coil from a pusher having a mutual locking surface. Patent Document 12 by Palermo shows an embolic coil that uses a mutual lock clasp (clasp) attached to both the pusher and the embolic coil. Patent Document 13 by Engelson shows a removable pusher-vascular occlusion assembly having a reciprocal lock ball and a keyhole type coupling. Patent Document 14 by Twyford et al. Shows a pusher-vascular occlusion coil assembly having a fixed proximally extending wire that holds the ball on its proximal end, and a pusher with a similar end. These two ends are mutually locked and disengaged when expelled from the distal tip of the catheter. Patent Document 15 by Palermo also shows a method for ejecting many coils from a single pusher by using a guide wire having a section that can be interconnected with the interior of a spirally wound coil. Patent Document 16 by Palermo et al. Shows a pusher having a throat at its distal end and a pusher passing through its axis. The pusher sheath can be released upon grasping the end of the embolic coil and then pushing the pusher axially located relative to the member found on the proximal end of the vascular occlusion coil.

However, none of the above documents refer to the devices described herein.<patcit num="1"><text>U.S. Pat. No. 4,994,069</text></patcit><patcit num="2"><text>U.S. Pat. No. 6,299,627</text></patcit><patcit num="3"><text>U.S. Pat. No. 5,624,461</text></patcit><patcit num="4"><text>U.S. Pat. No. 5,639,277</text></patcit><patcit num="5"><text>U.S. Pat. No. 5,649,949</text></patcit><patcit num="6"><text>U.S. Pat. No. 5,334,210</text></patcit><patcit num="7"><text>U.S. Pat. No. 5,537,338</text></patcit><patcit num="8"><text>U.S. Pat. No. 5,536,274</text></patcit><patcit num="9"><text>U.S. Pat. No. 5,690,666</text></patcit><patcit num="10"><text>U.S. Pat. No. 5,826,587</text></patcit><patcit num="11"><text>U.S. Pat. No. 5,234,437</text></patcit><patcit num="12"><text>U.S. Pat. No. 5,250,071</text></patcit><patcit num="13"><text>U.S. Pat. No. 5,261,916</text></patcit><patcit num="14"><text>U.S. Pat. No. 5,304,195</text></patcit><patcit num="15"><text>U.S. Pat. No. 5,312,415</text></patcit><patcit num="16"><text>U.S. Pat. No. 5,350,397</text></patcit>

<p> (Summary of the Invention) Therefore, the present invention includes new closed assemblies, methods of using these assemblies, and methods of making them.</p>

<p> Described herein are (i) a proximal portion having a composite three-dimensional relaxed form and a proximal portion having a first full diameter in this relaxed form, and (ii) the diameter of this proximal portion. A vascular occlusion device with a distal portion with a smaller diameter. This distal portion can be a two-dimensional or three-dimensional form, eg, one or more loops.</p><p> In any device described herein, the diameter of the distal portion is at least 10% less than the diameter of the proximal portion, more preferably at least 25% smaller than the diameter of the proximal portion. More preferably, it is at least 50% smaller than the diameter of the proximal portion, and even more preferably, at least 75% smaller than the diameter of the proximal portion.</p><p> Any device described herein further comprises a detachably cutable junction that can be attached to a delivery device (eg, a pusher element). This detachable junction can be positioned anywhere on the device, eg, one end or both ends of the device. In certain embodiments, these cuttable joints (s) are electrolytically detachable joints adapted for current application detachment, mechanically adapted for movement or pressure detachment. Detachable joints, heat-removable joints adapted for detachment by local delivery of heat to the joints, radiation-adapted joints adapted for detachment by delivery of electromagnetic radiation to the joints , Or a combination thereof.</p><p> In another aspect, a method of occluding a body cavity is described, which method comprises introducing a vascular occlusion device as described herein into the body cavity. In certain embodiments, this body cavity is an aneurysm.</p><p> In another aspect, the invention includes a method of occluding a body cavity, comprising the step of introducing any of the vascular occlusion devices described herein into the body cavity (eg, an aneurysm).</p><p> These and other embodiments of the invention may readily arise to those skilled in the art in light of the disclosure herein.</p>

(Explanation of the Invention) An embolic (eg, embolic) assembly is described. These assemblies described herein are found to be used in vascular and neurovascular indications and approach an aneurysm, eg, a small diameter, curved or otherwise vasculature. It is especially useful in treating aneurysms such as cerebral aneurysms that are difficult to treat. The methods of making and using these vascular occlusion elements also form aspects of the invention.

All documents cited herein (publications, patents and patent applications), whether above or below, are hereby incorporated by reference in their entirety.

As used herein and in the appended claims, the singular forms "a", "an", and "the" include multiple instructions unless the context explicitly indicates otherwise. Must be noted. Thus, for example, a reference to a device with "one loop" includes a device with two or more loops.

The self-forming coil design of the present invention is particularly useful in treating aneurysms. The designs described herein provide improvements to known devices, for example in terms of ease of deployment. Including a distal portion with a diameter smaller than the diameter of the major proximal portion of the device allows the device to be more easily placed in the target vessel. In particular, the embolic coil has a tendency for the first (distal) loop introduced into the aneurysm to leak into the parent vessel when this first (distal) loop is inserted. The design described herein is compounded during an aneurysm or other injury by making the distal loop substantially smaller than the more proximal loop and therefore smaller than the size of the aneurysm. Increasing the ease of introducing the shape coil, as a result, it "sits" in the aneurysm space without "winding" before the remaining loops are deployed.

Accordingly, the devices described herein include a proximal portion having a three-dimensional shape defining a first diameter and a second distal portion having a shape defining a second diameter. , This second diameter is substantially smaller than the first diameter above.

The three-dimensional shapes of these distal and proximal parts can be the same or different. For example, in certain embodiments, both the proximal and distal portions have a composite three-dimensional shape. "Complex" means any three-dimensional shape that defines multiple planes. Non-limiting examples of composite 3D shapes include spheres, ellipses, legislation, random, flower shapes, vortices, cones, spheres, non-overlapping loop structures, and the like. See, for example, U.S. Pat. Nos. 4,994,069; 5,624,461; 5,649,949; 5,522,822; 5,935,145; 5,690,666; 5,826,587; and 6,635,069. Similarly, the distal portion can take various of these forms.

Alternatively, in certain preferred embodiments, the proximal portion has a composite three-dimensional shape, while the distal portion has a two-dimensional shape (such as a loop or J shape). "Two-dimensional shape" refers to any shape in which the shape of that part of the device defines a plane. In order to have a diameter (eg, a diameter smaller than that of the total diameter of the proximal portion), the two-dimensional shape must include certain types of circular shapes, such as loops, J-shapes, ellipses, and the like. In a preferred embodiment, this distal portion is in a single loop form.

FIG. 1 shows an exemplary device with a composite embolic coil of any non-helical composite shape (10), with one or more distal loops (20) shown in darker gray. This most distal component (20) has a diameter (D) that is substantially smaller than the total diameter (A) of the loop in the composite morphological portion (10) of the device. The deployable catheter (35) is also shown in FIG.

In one preferred embodiment, the diameter of the distal portion (20) is approximately 75% of the total diameter in the composite portion (eg, the diameter of one or more loops). However, is the diameter of this distal portion (eg, loop) greater than 75% of the diameter of the proximal complex ("A") as long as the diameter of this distal portion is smaller than the diameter of the proximal portion? , Or may be small.

As shown in FIG. 1, preferably these two parts are made from the same material and are also preferably integrated with each other. However, it is also contemplated that these two parts can be made from different materials and / or they can be made separately and connected after manufacture.

The material (s) used in constructing the vascular occlusion device described herein can be any wide variety of materials; preferably, this material is such as a metal or polymer. It is a radiation opaque material. Suitable metals and alloys include platinum group metals, in particular platinum, rhodium, palladium, renium, and tungsten, gold, silver, tantalum, and alloys of these metals. These metals have significant radiation impermeability and, in their alloys, can be tailored to achieve a proper blend of flexibility and rigidity. They are also largely biologically inactive. Highly preferred are platinum / tungsten alloys.

The device can also be any of a wide variety of stainless steels, provided that some sacrifice of radiation impermeability is acceptable. From a mechanical point of view, the highly desired materials of construction are those that maintain their shape despite being under high stress. Certain "superelastic alloys" are nickel / titanium alloys (48-58 atomic% nickel, and optionally contain moderate amounts of iron); copper / zinc alloys (38-42 wt% zinc). Copper / zinc alloys containing 1-10% by weight beryllium, silicon, tin, aluminum, or gallium; or nickel / aluminum alloys (36-38% atomic% aluminum). Particularly preferred are the alloys described in US Pat. Nos. 3,174,851; 3,351,463; and 3,753,700. Particularly preferred is the titanium / nickel alloy known as "Nitinol". These are very tough alloys that can withstand significant bending without deformation, even when used as wires of very small diameters. When a superelastic alloy such as Nitinol is used in the device, the wire diameter of this coil is significantly smaller than that when a relatively more ductile platinum or platinum / tungsten alloy is used as the construction material. possible.

The devices also offer a wide variety of synthetic and natural polymers such as Dacron (polyester), polyglycolic acid, polylactic acid, fluoropolymers (polytetrafluoro-ethylene), Nylon (polyamide), or even silk. Can include. Other exemplary polymers that may be used are, without limitation, polyurethanes (including copolymers with soft segments containing esters, ethers and carbonates), ethers, acrylates (including cyanoacrylates), ethylene, propylene, butene, butadiene. , Styrene, and thermoplastic olefin elastomers) Olefin, polydimethylsiloxane-based polymers, polyethylene terephthalates, crosslinked polymers, non-crosslinked polymers, rayons, celluloses, cellulose derivatives such as nitrocellulose, natural rubbers, lactides, glycolides , Polyesters such as caprolactone, and their copolymers and acid derivatives, polyhydroxybutyrate and polyhydroxyvalerate and their copolymers, polyether esters such as polydioxynone, polymers such as cebasic acid polymers and copolymers. , Hexadecane dibasic acid and other dibasic acids, orthoesters can be included and used. When a polymer is used as the main component of a vascular occlusion member, it is preferably filled with a specific amount of known radiation opaque material such as powdered tantalum, powdered tungsten, bismuth oxide, barium sulfate, etc. ..

When deployed, the total diameter of the device is approximately between 2 and 30 mm (or any diameter between them), eg, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm. , 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, or 30mm. Most aneurysms within the cranial vasculature can be treated by one or more devices with these diameters. Of course, such a diameter is not an important aspect of the present invention.

Also articulated in the present invention is the attachment of various fibrous materials to the coils of the present invention for the purpose of adding thrombus forming properties to the resulting assembly. This fibrous material can be attached in a variety of ways. A series of looping fibers can loop through or be tied through a coil and follow axially below this coil. Another modification is by tying the Taft to a coil. The tuft can be connected at multiple sites through a coil, providing a large area of embolization site. The main coil can be covered by a braid of fibers. Methods for generating modified examples of the former are described in US Pat. Nos. 5,226,911 and 5,304,194 by Chee. Methods for producing fibrous braids are described in US Pat. No. 5,382,259, issued January 17, 1995, to Phelps and Van.

The coils described herein are also additional additives, such as any material that exhibits biological activity in vivo, such as co-solvents, plasticizers, coalescing solvents, bioactive agents, antimicrobials. Agents, antithrombotic agents (eg, heparin), antibiotics, dyes, radiopaque agents and / or ionic conductors can be included, which can be coated or produced using any suitable method. Can be incorporated into the above elements (s) between. See, for example, U.S. Patent Application Nos. 10 / 745,911, U.S. Pat. No. 6,585,754 and WO 02/51460 owned by Applicants, all of which are incorporated herein by reference. Thus, a bioactive material (eg, heparin) can be coated on the device and / or placed before, simultaneously with, or after placement of one or more devices as described herein.

One of the elements can also be fixed to each other in one or more positions. For example, as long as the various elements are thermoplastic, they can be melted or fused to the other elements of the device. Alternatively, they can be glued or otherwise fixed. In addition, the various elements can be fixed to each other in one or more positions.

(Methods of Use) The devices described herein are often introduced into selected sites using the procedures outlined below. This procedure can be used in treating a variety of diseases. For example, in the treatment of an aneurysm, the aneurysm itself is (partially or completely) filled with the assembly described herein.

Conventional catheter insertion and navigation techniques, including guide wires or flow direction devices, can be used to approach the site with the catheter. This mechanism can be fully advanced through the catheter, for example to place an occlusion device at the target site, but still a sufficient portion of the distal end of this delivery mechanism protrudes from the distal end of the catheter and is implanted. It can be to allow the withdrawal of possible vascular occlusion devices. For use in peripheral or neurosurgery, this delivery mechanism is typically about 100-200 cm in length, more usually 130-180 cm in length. The diameter of this delivery mechanism is typically in the range of 0.25 to about 0.90 mm. Briefly, the occlusion devices (and / or additional components) described herein are typically loaded into the carrier for introduction into a delivery catheter and are outlined below. It is introduced to the site selected using the procedure. This procedure can be used to treat a variety of diseases. For example, in the treatment of an aneurysm, the aneurysm itself can be filled with an embolus (eg, a vascular occlusion member and / or a liquid embolus and a bioactive material), which causes the formation of an embolus and is specific. At a later time, it is at least partially replaced by a newly angiogenic collagenous material formed around the implanted vascular occlusion device.

Selected sites are reached through the vasculature using a specially selected collection of catheters and / or guidewires. It is clear that this site is in a distant site, eg, in the brain, and there are some limited ways to reach this site. One widely accepted procedure is found in US Pat. No. 4,994,069 by Ritchart et al. It utilizes a microendovascular catheter as found in US Pat. No. 4,739,768 by Engelson. First of all, a large catheter is introduced through the site of entry in the vascular system. Typically, this can be through the femoral artery in the groin. Other sites of entry that are often selected are found in the neck and are generally well known by physicians performing this type of medicine. Once the introducer is in place, a guide catheter is then used to provide a safe route from this site of entry to the area near the site to be treated. For example, by treating a site in the human brain, from the site of entry in the femoral artery, through the aorta that extends to the heart, upwards, through the aortic arch, around the heart, and from the superior aspect of the aorta. A guide catheter that can extend downward through one can be selected. Guide wires and neurovascular catheters, such as those described in the Engelson patent, are then placed through the guide catheter. Once the distal end of the catheter is positioned at the site by placing its distal end through the use of radiopaque marker material and fluoroscopy, the guide catheter is removed. For example, if a guide wire is used to position a catheter, it is withdrawn from the catheter, and then, for example, an assembly containing a vascular occlusion device at its distal end is advanced through the catheter.

Once at the site of choice, the vascular occlusion device is extruded, for example, by being loaded onto a pusher wire. Preferably, the vaso-occlusive device is a GDC type junction that can be cut by mechanically or electrolytically cutable junctions (eg, thermal, electrolytic, electromechanical activation, coherent laser light or the application of other means. ) Is loaded onto the pusher wire. In addition, the vascular occlusion device is designed to include multiple withdrawal points, as described in US Pat. Nos. 6,623,493 and 6,533,801 owned by the Applicant and WO 02/45596 International Patent Publication. obtain. They are held in place by gravity, shape, size, capacitance, magnetic field or a combination thereof.

The procedures and modifications of the vascular occlusion devices described above, as well as methods of maintaining and using the present invention, will be apparent to those skilled in the art of medicine and surgery.

<figref num="1">FIG. 1 is an overview depicting an exemplary device as described herein. The proximal portion (10) has a total diameter (A) that is substantially larger than the diameter (D) of the distal portion (20).</figref>

It should be understood that this drawing describes an exemplary embodiment and should not be considered limiting scope.