Field of Endeavor
The present invention relates to treating aneurysms and more particularly to a shape memory polymer foam device for treating aneurysms.
State of Technology
U.S. Pat. No. 8,133,256 for shape memory polymer foams for endovascular therapies provides the state of technology information quoted below.
“In the general application, a vascular anomaly is treated using the device with the intent of stabilizing the anomaly from further expansion and possible rupture. The device is delivered endovascularly to the site for therapy via a catheter. The catheter may be previously placed using a conventional guidewire or the device may be installed using the guidewire. Once the catheter is placed near the therapeutic site, the device is placed into the anomaly with the guidewire and guided visually by radiology. The device is then held in place and the foam is actuated to expand, filling the anomaly. Once expanded, the foam will stay in place on its own or an additional aid will be used to hold it in place; for example, a diaphragm for the aneurysm or a stent for the AVM. The foam is released from the guidewire or catheter via the expansion process or following actuation by known techniques. The guidewire and/or catheter is then retracted and the therapy is completed. Should there be a misplacement of the foam, retrieval is possible using another shape-memory polymer device or other conventional techniques.”
“Shape-memory materials have the useful ability of being formable into a primary shape, being reformable into a stable secondary shape, and then being controllably actuated to recover their primary shape. Both metal alloys and polymeric materials can have shape memory. In the case of metals, the shape-memory effect arises from thermally induced solid phase transformations in which the lattice structure of the atoms changes, resulting in macroscopic changes in modulus and dimensions. In the case of polymeric materials, the primary shape is obtained after processing and fixed by physical structures or chemical crosslinking. The secondary shape is obtained by deforming the material while is an elastomeric state and that shape is fixed in one of several ways including cooling the polymer below a crystalline, liquid crystalline, or glass transition temperature; by inducing additional covalent or ionic crosslinking, etc.”
“While in the secondary shape some or all of the polymer chains are perturbed from their equilibrium random walk conformation, having a certain degree of bulk orientation. The oriented chains have a certain potential energy, due to their decreased entropy, which provides the driving force for the shape recovery. However, they do not spontaneously recover due to either kinetic effects (if below their lower Tg) or physical restraints (physical or chemical crosslinks). Actuation then occurs for the recovery to the primary shape by removing that restraint, e.g., heating the polymer above its glass transition or melting temperature, removing ionic or covalent crosslinks, etc. Other types of polymers which undergo shape memory behavior due to photon induced conformational transformations, conformational changes (e.g., rod-coil transition) due to changes in chemical environment (pH, ionic strength, etc.), or structural changes due to imposed fields (e.g., electric, magnetic, . . . ) may also be used. Both shape memory alloys (SMAs) and shape memory polymers (SMPs) can be used for the shape memory material of the present invention.”
“A shape memory material therapeutic device has advantages over existing therapeutic devices of being able to be moved more easily through the catheter to the point of placement, A shape memory material therapeutic can be placed more precisely within the geometry of the vascular disorder, and there is a higher degree of control over the expansion process while the device was being held in the desired position. A shape memory material therapeutic can be controllably expanded while being held in precise placement. A shape memory material therapeutic expands to its secondary shape within a few seconds, which is much faster than current expandable hydrogel based devices. The modulus of the devices can be accurately controlled so that expansion forces are low and no damage is done to areas of the vascular lumen.
The shape memory material device is expandable from 100% to 10000% by volume. The shape memory material device is actuated by one of several means including electromagnetic energy delivered optically. The shape memory material device is used to occlude part or all of a lumen, aneurysm, artiovascular malformation, or other physical anomaly.”
Features and advantages of the present invention will become apparent from the following description. Applicants are providing this description, which includes drawings and examples of specific embodiments, to give a broad representation of the invention. Various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this description and by practice of the invention. The scope of the invention is not intended to be limited to the particular forms disclosed and the invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims.
The present invention provides a shape memory polymer foam system for treating aneurysms. In one embodiment the present invention provides an apparatus for treating an aneurysm in a blood vessel or vein, wherein the aneurysm has a dome, an interior, and a neck. The apparatus provides a shape memory polymer foam in the interior of the aneurysm between the dome and the neck. The shape memory polymer foam has pores that include a first multiplicity of pores having a first pore size and a second multiplicity of pores having a second pore size. The second pore size is larger than said first pore size. The first multiplicity of pores are located in the neck of the aneurysm. The second multiplicity of pores are located in the dome of the aneurysm. This provides a shape memory polymer foam system with foam porosity, permeability, and shape to stagnate the blood flow within the aneurysm and to promote thrombus and collagen formation throughout the SMP foam.
The present invention provides a shape memory polymer foam system with a gradation of foam pore size in a continuous fashion from one end of the single piece of foam to the other end. This places the least permeable portion of foam nearest the parent artery, where the blood flow has the highest speed. Consequently, the small pore sizes near the aneurysm neck rapidly decelerate the flow as it enters the aneurysm. Near the aneurysm fundus, where the blood flow has a much smaller speed, the pore sizes are larger since it is not necessary to further decelerate the flow in this region.
The present invention has two major advantages. First, it allows for smaller treatment devices since only the necessary amount of foam material required for healing is incorporated into the device. The result is a compact design that can easily reach small intracranial arteries where aneurysms typically form. Second, the present invention preserves essential blood flow to vessels that often line the aneurysm wall.
The invention is susceptible to modifications and alternative forms. Specific embodiments are shown by way of example. It is to be understood that the invention is not limited to the particular forms disclosed. The invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims.
The accompanying drawings, which are incorporated into and constitute a part of the specification, illustrate specific embodiments of the invention and, together with the general description of the invention given above, and the detailed description of the specific embodiments, serve to explain the principles of the invention.
Referring to the drawings, to the following detailed description, and to incorporated materials, detailed information about the invention is provided including the description of specific embodiments. The detailed description serves to explain the principles of the invention. The invention is susceptible to modifications and alternative forms. The invention is not limited to the particular forms disclosed. The invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims.
The present invention provides systems for treating aneurysms. This invention has particular advantage for treating cranial aneurysms and will be described by various embodiments relating to cranial aneurysms; however it is to be understood that the scope of the invention is not intended to be limited to the particular embodiments and forms disclosed and the invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims.
A cranial aneurysm is a condition that is often asymptomatic until the time of rupture. Subarachnoid hemorrhage associated with aneurysmal rupture is a potentially lethal event with a mortality rate as high as 50 percent. Many patients who survive the initial hemorrhage have permanent disability. A cranial aneurysm, also called cerebral or brain aneurysm, is a disorder in the veins or vascular system of the brain. Cerebral veins or arteries become weak and cause the blood vessels to balloon or dilate. Aneurysms are often found in the Circle of Willis, which is a group of arteries found at the base of the brain. The majority, about 85%, occur in the anterior part of this area. They often happen in the parts of cerebrovascular system that provide blood to the anterior and middle sections of the brain, usually with the internal carotid arteries and their main branches. There are different kinds of aneurysms based on size and shape. Those less than 15 mm are considered small. A size of 15 to 25 mm means the aneurysms are large while those found over 50 mm are considered super giants. The most common shape of aneurysms is saccular; this means it has some saccular outpouching. Some of these saccular aneurysms also have a stem or neck; these are called berry aneurysms. Those without stems are called fusiform aneurysms. Congenital defects or head trauma can lead to aneurysms. The more common cause is high blood pressure and atherosclerosis or the buildup of fatty deposits in the arteries. This is a greater cause for concern in the midst of the obesity problem in developed countries. This disorder does not adhere to any age range, but occurs more often in adults. It also favors women with a ratio of 3 to 2.
The present invention provides systems for treating these intracranial aneurysms through the endovascular delivery of a shape memory polymer foam (SMP) device. The systems function by producing flow conditions within the post-treatment aneurysm that optimize the body's healing response to the treatment procedure. This invention includes systems for customizing the SMP foam structure of the device to obtain flow conditions within the post-treatment aneurysm that optimize the body's healing response to the treatment procedure. In various embodiments the present invention provides systems for designing the SMP foam porosity, permeability, and shape to stagnate the blood flow within the aneurysm and to promote thrombus and collagen formation throughout the SMP foam.
The system of the present invention provides a number of advantages. For example, it allows for smaller treatment devices since only the necessary amount of SMP foam material required for healing is incorporated into the device. The result is a compact design that can easily reach small intracranial arteries where aneurysms typically form. Also, the system of the present invention preserves essential blood flow to vessels that often line the aneurysm wall by including channels that deliver blood from the parent artery to these vessels. Such transport will not only maintain the health of tissue downstream of these vessels, but will also provide a robust means of promoting the body's healing response to the treatment procedure. The current FDA-approved technique of treating aneurysms with detachable metal coils and/or an endoluminal stent do not provide this advantage since the coils randomly fill the aneurysm, thereby occluding these vessels.
The present invention is further described and illustrated by a number of examples of systems constructed in accordance with the present invention. Various changes and modifications of these examples will be apparent to those skilled in the art from the description of the examples and by practice of the invention. The scope of the invention is not intended to be limited to the particular examples disclosed and the invention covers all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the claims.
Referring now to the drawings and in particular to
Referring now to
As illustrated in
The device is then held in place and the SMP foam is actuated to expand, filling the aneurysm. Once expanded, the SMP foam will stay in place on its own or an additional aid can be used to hold it in place. The SMP foam is released from the guidewire or catheter via the expansion process or following actuation by known techniques. The guidewire and/or catheter is then retracted and the treatment is completed.
Referring now to
Referring now to
As illustrated in
Referring now to
The SMP foam unit 502 has a gradation of foam pore size in a continuous fashion from one end of the single piece of SMP foam to the other end. This places the least permeable portion of the SMP foam nearest the parent artery, where the blood flow has the highest speed. Consequently, the small pore sizes near the aneurysm neck rapidly decelerate the flow as it enters the aneurysm. Near the aneurysm fundus, where the blood flow has a much smaller speed, the pore sizes are larger since it is not necessary to decelerate the flow in this region. Through this gradation of pore sizes, the total amount of polymer material comprising the device can be reduced.
Referring now to
Referring now to
Referring now to
Referring now to
Referring now to
Referring now to
Referring now to
Referring now to
Referring now to
Referring now to
While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
This application is a Continuation of Application Ser. No. 13/798,740 filed Mar. 13, 2013, the disclosure of which is hereby incorporated by reference in its entirety for all purposes.
The United States Government has rights in this invention pursuant to Contract No. DE-AC52-07NA27344 between the United States Department of Energy and Lawrence Livermore National Security, LLC for the operation of Lawrence Livermore National Laboratory.
Number | Name | Date | Kind |
---|---|---|---|
3095877 | Rowan | Jul 1963 | A |
5392787 | Yoon | Feb 1995 | A |
5769884 | Solovay | Jun 1998 | A |
5891558 | Bell | Apr 1999 | A |
5951599 | McCrory | Sep 1999 | A |
6165193 | Greene, Jr. | Dec 2000 | A |
6238403 | Greene, Jr. | May 2001 | B1 |
6315709 | Garibaldi | Nov 2001 | B1 |
6346117 | Greenhalgh | Feb 2002 | B1 |
6375668 | Gifford | Apr 2002 | B1 |
6602261 | Greene, Jr. | Aug 2003 | B2 |
6692510 | West | Feb 2004 | B2 |
6723108 | Jones | Apr 2004 | B1 |
7014645 | Greene, Jr. | Mar 2006 | B2 |
7491214 | Greene, Jr. | Feb 2009 | B2 |
8133256 | Wilson et al. | Mar 2012 | B2 |
8771294 | Sepetka | Jul 2014 | B2 |
8870909 | Cox | Oct 2014 | B2 |
9095342 | Becking | Aug 2015 | B2 |
9155671 | Fuller | Oct 2015 | B2 |
9445819 | Grace | Sep 2016 | B2 |
9629636 | Fogarty | Apr 2017 | B2 |
10010327 | Wilson | Jul 2018 | B2 |
20020143349 | Gifford, III | Oct 2002 | A1 |
20030187473 | Berenstein | Oct 2003 | A1 |
20030195553 | Wallace | Oct 2003 | A1 |
20030199887 | Ferrera | Oct 2003 | A1 |
20040098027 | Teoh | May 2004 | A1 |
20040143288 | Searle | Jul 2004 | A1 |
20050015110 | Fogarty | Jan 2005 | A1 |
20050182428 | Bearinger et al. | Aug 2005 | A1 |
20060052816 | Bates | Mar 2006 | A1 |
20060116712 | Sepetka | Jun 2006 | A1 |
20070135907 | Wilson | Jun 2007 | A1 |
20080097495 | Feller, III | Apr 2008 | A1 |
20090112249 | Miles | Apr 2009 | A1 |
20090112251 | Qian | Apr 2009 | A1 |
20100076463 | Mavani | Mar 2010 | A1 |
20100094335 | Gerberding | Apr 2010 | A1 |
20100228184 | Mavani | Sep 2010 | A1 |
20110022149 | Cox | Jan 2011 | A1 |
20110046658 | Connor | Feb 2011 | A1 |
20110144669 | Becking | Jun 2011 | A1 |
20110144686 | Wilson et al. | Jun 2011 | A1 |
20120158034 | Wilson | Jun 2012 | A1 |
20120253369 | Morsi | Oct 2012 | A1 |
20140135812 | Divino | May 2014 | A1 |
Number | Date | Country |
---|---|---|
2003082128 | Oct 2003 | WO |
2006111801 | Oct 2006 | WO |
2007006139 | Jun 2011 | WO |
Entry |
---|
International Search Report and Written Opinion for PCT/US14/023712, corresponding to U.S. Appl. No. 13/798,740, 10 pages. |
Number | Date | Country | |
---|---|---|---|
20170252045 A1 | Sep 2017 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 13798740 | Mar 2013 | US |
Child | 15599133 | US |