Patent Publication Number: US-2020281603-A1

Title: Filamentary devices for treatment of vascular defects

Description:
RELATED APPLICATIONS 
     This application is a continuation of and claims priority from U.S. patent application Ser. No. 15/656,879, filed Jul. 21, 2017, which is a continuation of and claims priority from U.S. patent application Ser. No. 13/771,632, filed Feb. 20, 2013, now abandoned, which is a continuation of and claims priority from U.S. patent application Ser. No. 12/434,465, filed May 1, 2009, by Cox et al., titled “Filamentary Devices for Treatment of Vascular Defects”, now issued as U.S. Pat. No. 9,597,087, which claims the benefit of priority under 35 U.S.C. section 119(e) from U.S. Provisional Patent Application No. 61/050,124 filed May 2, 2008, by Cox et al. titled “Filamentary Devices for Treatment of Vascular Defects”, all of which are incorporated by reference herein in their entirety. 
     This application is related to Provisional Patent Application Ser. No. 61/044,822, filed Apr. 14, 2008, entitled “Methods and Devices for Treatment of Vascular Defects”, naming Brian J. Cox et al. as inventors and designated by attorney docket number SMI-0103-PV2, Provisional Patent Application Ser. No. 60/941,928, filed on Jun. 4, 2007, entitled “Method and Apparatus for Treatment of a Vascular Defect,” naming Brian J. Cox et al. as inventors, and designated by attorney docket number SMI-0101-PV, U.S. Provisional Patent Application Ser. No. 60/094,683, filed on Jul. 9, 2007, entitled “Vascular Occlusion Devices,” naming Brian J. Cox et al. as inventors, and designated by attorney docket number SMI-0102-PV, and U.S. Provisional Patent Application Ser. No. 60/097,366, filed on Sep. 11, 2007, entitled “Method and Apparatus for Treatment of a Vascular Defect,” naming Dean Schaefer et al. as inventors, and designated by attorney docket number SMI-0103-PV, International PCT Patent Application No. PCT/US2008/065694, published Dec. 11, 2008, number WO 2008/151204, filed Jun. 3, 2008, entitled “Methods and Devices for Treatment of Vascular Defects”, naming Brian J. Cox et al. as inventors and designated by attorney docket number SMI-0103-PC, which are all incorporated by reference herein in their entirety. 
    
    
     FIELD OF THE INVENTION 
     Embodiments of devices and methods herein are directed to blocking a flow of fluid through a tubular vessel or into a small interior chamber of a saccular cavity or vascular defect within a mammalian body. More specifically, embodiments herein are directed to devices and methods for treatment of a vascular defect of a patient including some embodiments directed specifically to the treatment of cerebral aneurysms of patients. 
     BACKGROUND 
     The mammalian circulatory system is comprised of a heart, which acts as a pump, and a system of blood vessels which transport the blood to various points in the body. Due to the force exerted by the flowing blood on the blood vessel the blood vessels may develop a variety of vascular defects. One common vascular defect known as an aneurysm results from the abnormal widening of the blood vessel. Typically, vascular aneurysms are formed as a result of the weakening of the wall of a blood vessel and subsequent ballooning and expansion of the vessel wall. If, for example, an aneurysm is present within an artery of the brain, and the aneurysm should burst with resulting cranial hemorrhaging, death could occur. 
     Surgical techniques for the treatment of cerebral aneurysms typically involve a craniotomy requiring creation of an opening in the skull of the patient through which the surgeon can insert instruments to operate directly on the patient&#39;s brain. For some surgical approaches, the brain must be retracted to expose the parent blood vessel from which the aneurysm arises. Once access to the aneurysm is gained, the surgeon places a clip across the neck of the aneurysm thereby preventing arterial blood from entering the aneurysm. Upon correct placement of the clip the aneurysm will be obliterated in a matter of minutes. Surgical techniques may be effective treatment for many aneurysms. Unfortunately, surgical techniques for treating these types of conditions include major invasive surgical procedures which often require extended periods of time under anesthesia involving high risk to the patient. Such procedures thus require that the patient be in generally good physical condition in order to be a candidate for such procedures. 
     Various alternative and less invasive procedures have been used to treat cerebral aneurysms without resorting to major surgery. Some such procedures involve the delivery of embolic or filling materials into an aneurysm. The delivery of such vaso-occlusion devices or materials may be used to promote hemostasis or fill an aneurysm cavity entirely. Vaso-occlusion devices may be placed within the vasculature of the human body, typically via a catheter, either to block the flow of blood through a vessel with an aneurysm through the formation of an embolus or to form such an embolus within an aneurysm stemming from the vessel. A variety of implantable, coil-type vaso-occlusion devices are known. The coils of such devices may themselves be formed into a secondary coil shape, or any of a variety of more complex secondary shapes. Vaso-occlusive coils are commonly used to treat cerebral aneurysms but suffer from several limitations including poor packing density, compaction due to hydrodynamic pressure from blood flow, poor stability in wide-necked aneurysms and complexity and difficulty in the deployment thereof as most aneurysm treatments with this approach require the deployment of multiple coils. 
     Another approach to treating aneurysms without the need for invasive surgery involves the placement of sleeves or stents into the vessel and across the region where the aneurysm occurs. Such devices maintain blood flow through the vessel while reducing blood pressure applied to the interior of the aneurysm. Certain types of stents are expanded to the proper size by inflating a balloon catheter, referred to as balloon expandable stents, while other stents are designed to elastically expand in a self-expanding manner. Some stents are covered typically with a sleeve of polymeric material called a graft to form a stent-graft. Stents and stent-grafts are generally delivered to a preselected position adjacent a vascular defect through a delivery catheter. In the treatment of cerebral aneurysms, covered stents or stent-grafts have seen very limited use due to the likelihood of inadvertent occlusion of small perforator vessels that may be near the vascular defect being treated. 
     In addition, current uncovered stents are generally not sufficient as a stand-alone treatment. In order for stents to fit through the microcatheters used in small cerebral blood vessels, their density is usually reduced such that when expanded there is only a small amount of stent structure bridging the aneurysm neck. Thus, they do not block enough flow to cause clotting of the blood in the aneurysm and are thus generally used in combination with vaso-occlusive devices, such as the coils discussed above, to achieve aneurysm occlusion. 
     A number of aneurysm neck bridging devices with defect spanning portions or regions have been attempted; however, none of these devices have had a significant measure of clinical success or usage. A major limitation in their adoption and clinical usefulness is the inability to position the defect spanning portion to assure coverage of the neck. Existing stent delivery systems that are neurovascular compatible (i.e. deliverable through a microcatheter and highly flexible) do not have the necessary rotational positioning capability. Another limitation of many aneurysm bridging devices described in the prior art is the poor flexibility. Cerebral blood vessels are tortuous, and a high degree of flexibility is required for effective delivery to most aneurysm locations in the brain. 
     What has been needed are devices and methods for delivery and use in small and tortuous blood vessels that can substantially block the flow of blood into an aneurysm, such as a cerebral aneurysm, with a decreased risk of inadvertent aneurysm rupture or blood vessel wall damage. In addition, what has been needed are methods and devices suitable for blocking blood flow in cerebral aneurysms over an extended period of time without a significant risk of deformation, compaction or dislocation. 
     SUMMARY 
     Some embodiments of a device for treatment of a patient&#39;s vasculature include a self-expanding resilient permeable shell having a proximal end, a distal end, and a longitudinal axis. The permeable shell also includes a plurality of elongate resilient filaments with a woven structure secured relative to each other at proximal ends and distal ends thereof. The permeable shell has a radially constrained elongated state configured for delivery within a microcatheter with the thin woven filaments extending longitudinally from the proximal end to the distal end radially adjacent each other along a length of the filaments. The permeable shell also has an expanded relaxed state with a globular and longitudinally shortened configuration relative to the radially constrained state with the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal end and distal end including a plurality of openings in the shell formed between the woven filaments, the largest of said openings being configured to allow blood flow through the openings at a velocity below a thrombotic threshold velocity. The permeable shell may also include a configuration wherein at least the distal end has a reverse bend in an everted recessed configuration such that the secured distal ends of the filaments are withdrawn axially within the nominal contour of the permeable shell structure in the expanded state. 
     Some embodiments of a device for treatment of a patient&#39;s vasculature include a self-expanding resilient permeable shell having a proximal end, a distal end, and a longitudinal axis. The permeable shell may also include a plurality of elongate resilient filaments including large filaments and small filaments of at least two different transverse dimensions with a woven structure secured relative to each other at proximal ends and distal ends thereof. The permeable shell may also include a radially constrained elongated state configured for delivery within a microcatheter with the thin woven filaments extending longitudinally from the proximal end to the distal end radially adjacent each other along a length of the filaments. The permeable shell also has an expanded relaxed state with a globular and longitudinally shortened configuration relative to the radially constrained state with the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal end and distal end including a plurality of openings in the shell formed between the woven filaments. The permeable shell may be configured such that at least the distal end has a reverse bend in an everted recessed configuration such that the secured distal ends of the filaments are withdrawn axially within the nominal permeable shell structure in the expanded state. 
     Some embodiments of a device for treatment of a patient&#39;s vasculature include a self-expanding resilient permeable shell having a proximal end, a distal end, and a longitudinal axis. The permeable shell also includes a plurality of elongate resilient filaments including large filaments and small filaments of different transverse diameters with a woven structure secured relative to each other at proximal ends and distal ends thereof. The permeable shell may also include a radially constrained elongated state configured for delivery within a microcatheter with the woven filaments extending longitudinally from the proximal end to the distal end radially adjacent each other along a length of the filaments. The permeable shell also has an expanded relaxed state with a globular and longitudinally shortened configuration relative to the radially constrained state with a major transverse diameter, the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal end and distal end, and including a plurality of openings in the shell formed between the woven filaments. The permeable shell may also be configured such that at least the distal end has a reverse bend in an everted recessed configuration such that the secured distal ends of the filaments are withdrawn axially within the nominal permeable shell structure in the expanded state. In addition, the permeable shell may have properties such that the diameter of the permeable shell in an expanded state, number and diameter of large filaments and number and diameter of small filaments are configured such that the permeable shell in an expanded state has a radial stiffness of about 0.014 pounds force (lbf) to about 0.284 lbf defined by the expression (1.2×10 6  lbf/D 4 )(N l d l   4 +N s d s   4 ) where D is a diameter of the permeable shell in the expanded state in inches, N l  is the number of large filaments in the permeable shell, N s  is the number of small filaments in the permeable shell, d l  is the diameter of the large filaments in inches, and d s  is the diameter of the small filaments in inches. The equation above contemplates two wire sizes, however, the equation is also applicable to embodiments having one wire size in which case di will be equal to d s . 
     Some embodiments of a device for treatment of a patient&#39;s vasculature include a self-expanding resilient permeable shell having a proximal end, a distal end, and a longitudinal axis. The permeable shell also has a plurality of elongate resilient filaments including large filaments and small filaments of different transverse diameters with a woven structure secured relative to each other at proximal ends and distal ends thereof. The permeable shell may also include a radially constrained elongated state configured for delivery within a microcatheter with the thin woven filaments extending longitudinally from the proximal end to the distal end radially adjacent each other along a length of the filaments. The permeable shell has an expanded relaxed state with a globular and longitudinally shortened configuration relative to the radially constrained state with a major transverse diameter, the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal end and distal end, and including a plurality of openings in the shell formed between the woven filaments. The permeable shell may also be configured such that at least the distal end has a reverse bend in an everted recessed configuration such that the secured distal ends of the filaments are withdrawn axially within the nominal permeable shell structure in the expanded state. The permeable shell may further have properties such that the diameter of the permeable shell in an expanded state, number of all filaments and diameter of the small filaments are configured such that the maximum opening size of a portion of the permeable shell in an expanded state that spans a vascular defect opening or vascular defect neck is less than about 0.016 inches with the maximum pore or opening size defined by the expression (1.7/N T )(πD−N T /2d w ) where D is a diameter of the permeable shell in the expanded state in inches, N T  is the total number of filaments in the permeable shell, and d W  is the diameter of the small filaments in inches. The pore size for an opening is defined herein by the largest circular shape that may be disposed within the opening of a braided filament structure. 
     Some embodiments of a device for treatment of a patient&#39;s vasculature include a self-expanding resilient permeable shell having a proximal end, a distal end, and a longitudinal axis. The permeable shell further includes a plurality of elongate resilient filaments including large filaments and small filaments of different transverse diameters with a woven structure secured relative to each other at proximal ends and distal ends thereof. The permeable shell may also have a radially constrained elongated state configured for delivery within a microcatheter with the woven filaments extending longitudinally from the proximal end to the distal end radially adjacent each other along a length of the filaments. The permeable shell also includes an expanded relaxed state with a globular and longitudinally shortened configuration relative to the radially constrained state with a major transverse diameter, the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal end and distal end, and including a plurality of openings in the shell formed between the woven filaments. The permeable shell may also be configured such that at least the distal end has a reverse bend in an everted recessed configuration such that the secured distal ends of the filaments are withdrawn axially within the nominal permeable shell structure in the expanded state. The permeable shell may also have properties such that the diameter of the permeable shell in an expanded state, number and diameter of large filaments and number and diameter of small filaments are configured such that the permeable shell in a constrained state has an outer transverse diameter of less than about 0.04 inches defined by the expression 1.48((N l d l   2 +N s d s   2 )) 1/2  where N l  is the number of large filaments in the permeable shell, N s  is the number of small filaments in the permeable shell, d l  is the diameter of the large filaments in inches, and d s  is the diameter of the small filaments in inches. 
     Some embodiments of a method of treating a vascular defect of a patient include providing a device for treatment of a patient&#39;s vasculature comprising a self-expanding resilient permeable shell of woven filaments, the permeable shell having a proximal end, a distal end, a longitudinal axis, a radially constrained elongated state configured for delivery within a microcatheter with the woven filaments extending longitudinally from the proximal end to the distal radially adjacent each other. The permeable shell may also have an expanded relaxed state with a globular and axially shortened configuration relative to the constrained state with the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal end and distal end with the shell having a reverse bend at each end in an everted recessed configuration such that a hub at the distal end is withdrawn axially within the permeable shell structure. The permeable shell also has and a plurality of openings in the shell formed between the woven filaments. Once provided, a delivery system is advanced within a patient&#39;s body such that a distal end of the delivery system is disposed at a position adjacent or within a vascular defect to be treated. The device is then axially advanced within the delivery system while in a radially constrained state with an elongate delivery apparatus which has a distal end releasably secured to a proximal end of the device. The device is further advanced distally until the device emerges from a distal end of the delivery system. The device is further advanced from the distal end of the delivery system until it is deployed such that the woven filaments of the device radially expand from their radially constrained state, and expand into a globular configuration of the permeable shell. The deployed device then covers and acutely occludes at least a portion of an opening or neck of the vascular defect due to the pore size of the permeable shell which slows a flow of blood therethrough to a velocity below a thrombotic threshold velocity. 
     Some methods of occluding a vascular defect of a patient&#39;s vasculature include providing an expandable, porous vascular occlusion device formed from a woven shell of a plurality of filamentary members that are connected to each other on at least the proximal ends of the members forming a substantially closed globular structure with a shape that approximates or is slightly larger than a size and shape of the vascular defect and wherein the distal ends of the filamentary members are recessed within a nominal surface contour of the globular structure of the device. Once the device is provided, the device may be collapsed for delivery into the vascular system of the patient. The collapsed device may then be inserted through an incision in the patient&#39;s body and the device released and expanded at the vascular defect such that an outer surface contour of the device substantially fills the vascular defect. The device then substantially occludes the vascular defect acutely and becomes substantially covered with clotted blood. 
     Some embodiments of a method of treating a cerebral aneurysm within a cerebral vasculature of a patient include providing a microcatheter having a proximal end, a distal end, and a lumen therebetween. The device for treatment of an aneurysm within a patient&#39;s vasculature includes a self-expanding resilient permeable shell having a proximal end, a distal end, and a longitudinal axis. The device includes a plurality of elongate resilient filaments with a woven structure, wherein the plurality of filaments includes small filaments and large filaments, wherein the small filaments have a transverse dimension smaller than the transverse dimension of the large filaments, the woven structure having a radially constrained elongated state configured for delivery within a microcatheter with the thin woven filaments extending longitudinally from the proximal end to the distal end radially adjacent each other along a length of the filaments, wherein the filaments are bundled and secured to each other at a proximal end, wherein a ratio of the total cross-sectional area of small filaments to the total cross-sectional area of large filaments is between 0.56 and 1.89. The distal end of the microcatheter may be advanced to a region of interest within a cerebral artery. The device may be advanced through the lumen and out of the distal end of the microcatheter such that the permeable shell deploys within the cerebral aneurysm, wherein the permeable shell expands to an expanded state within the cerebral aneurysm, the expanded relaxed state having a longitudinally shortened configuration relative to the radially constrained state. The microcatheter may be withdrawn from the cerebral artery, wherein the permeable shell is the only implant delivered into the cerebral aneurysm through the microcatheter before the micro catheter is withdrawn. 
     Some embodiments of a delivery system for deployment of a device for treatment of a patient&#39;s vasculature include a microcatheter having an inner lumen extending a length thereof and a device for treatment of a patient&#39;s vasculature disposed within the inner lumen of the microcatheter. The device also includes a self-expanding resilient permeable shell of thin coupled filaments, the permeable shell having a proximal end, a distal end, a longitudinal axis, a radially constrained elongated state configured for delivery within a microcatheter with the thin woven filaments extending longitudinally from the proximal end to the distal radially adjacent each other. The permeable shell also has an expanded relaxed state with a globular and axially shortened configuration relative to the constrained state with the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal end and distal end. The permeable shell may further include a reverse bend at each end in an everted recessed configuration such that a hub at the distal end is disposed axially within the permeable shell structure. The permeable shell also has a plurality of openings formed between the woven filaments, the permeable shell further having a portion when in the expanded relaxed state that is configured to span an opening of a patient&#39;s vascular defect. The delivery system further includes an elongate delivery apparatus having a proximal end and a distal end releasably secured to a proximal hub of the device. 
     Some embodiments of a method of manufacturing a device for treatment of a patient&#39;s vasculature include braiding a plurality of elongate resilient filaments over a cylindrically shaped mandrel forming a braided tubular member. The elongate filaments of the braided tubular member may then be heat set in an expanded relaxed state with a globular and axially shortened configuration relative to a constrained state with the woven filaments forming the self-expanding resilient permeable shell in a smooth path radially expanded from a longitudinal axis of the device between a proximal end and a distal end of the device with the shell having a reverse bend at the distal end in an everted recessed configuration such that a hub at the distal end is withdrawn disposed within the permeable shell structure and a plurality of openings in the shell are formed between the woven filaments. The proximal ends of the filaments are then secured together, and the distal ends of the filaments are secured together. 
     Some embodiments of a device for treatment of a patient&#39;s vasculature include a self-expanding resilient permeable shell of thin interconnected filaments that serves as a support structure and integral defect spanning structure, the permeable shell having a first end, a second end, a longitudinal axis, a constrained cylindrical state configured for delivery within a microcatheter with the thin interconnected filaments extending from the first end to the second end. The permeable shell also has an expanded relaxed state with a globular and axially shortened configuration relative to the constrained state with filaments forming a smooth arc between the first end and second end with a reverse bend at each end in an everted recessed configuration. The permeable shell further has a defect spanning portion when in the expanded relaxed state that is configured to span an opening of a patient&#39;s vascular defect. 
     Some embodiments of a method of treating a vascular defect include providing a device for treatment of a patient&#39;s vasculature having a self-expanding resilient permeable shell of thin interconnected filaments that serves as a support structure and integral defect spanning structure. The permeable shell also has a first end, a second end, a longitudinal axis, a constrained cylindrical state configured for delivery within a microcatheter with the thin interconnected filaments extending from the first end to the second end. The permeable shell also has an expanded relaxed state with a globular and axially shortened configuration relative to the constrained state with filaments forming a smooth arc between the first end and second end with a reverse bend at each end in an everted recessed configuration. The permeable shell further has a defect spanning portion when in the expanded relaxed state that is configured to span an opening of a patient&#39;s vascular defect. Once provided, the delivery system may be advanced to a position adjacent a vascular defect to be treated and positioned with a distal end disposed inside the vascular defect. The device may then be deployed such that the permeable shell self-expands and the defect spanning portion of the permeable shell covers at least a portion of the defect opening or neck. 
     Some embodiments of a device for treatment of a patient&#39;s vasculature include a self-expanding resilient permeable shell of thin interconnected filaments that serves as a support structure and integral defect spanning structure. The permeable shell also has a first end, a second end, a longitudinal axis, a constrained cylindrical state configured for delivery within a microcatheter with the thin interconnected filaments extending from the first end to the second end. The permeable shell also has an expanded relaxed state with a globular and axially shortened configuration relative to the constrained state with filaments forming a smooth arc between the first end and second end with a reverse bend at each end in an everted recessed configuration. The permeable shell further includes a defect spanning portion when in the expanded relaxed state that is configured to span an opening of a patient&#39;s vascular defect. 
     Some embodiments of a method of treating a vascular defect include providing a device for treatment of a patient&#39;s vasculature having a self-expanding resilient permeable shell of thin interconnected filaments that serves as a support structure and integral defect spanning structure. The permeable shell also has a first end, a second end, a longitudinal axis, a constrained cylindrical state configured for delivery within a microcatheter with the thin interconnected filaments extending from the first end to the second end. The permeable shell further includes an expanded relaxed state with a globular and axially shortened configuration relative to the constrained state with filaments forming a smooth arc between the first end and second end with a reverse bend at each end in an everted recessed configuration. The permeable shell also has a defect spanning portion when in the expanded relaxed state that is configured to span an opening of a patient&#39;s vascular defect. Once the device has been provided, a delivery system may be advanced to a position adjacent a vascular defect to be treated. The device is then positioned inside the vascular defect and deployed such that the permeable shell self-expands and the defect spanning portion of the permeable shell covers at least a portion of the defect opening or neck. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an elevation view of an embodiment of a device for treatment of a patient&#39;s vasculature and a plurality of arrows indicating inward radial force. 
         FIG. 2  is an elevation view of a beam supported by two simple supports and a plurality of arrows indicating force against the beam. 
         FIG. 3  is a bottom perspective view of an embodiment of a device for treatment of a patient&#39;s vasculature. 
         FIG. 4  is an elevation view of the device for treatment of a patient&#39;s vasculature of  FIG. 3 . 
         FIG. 5  is a transverse cross sectional view of the device of  FIG. 4  taken along lines  5 - 5  in  FIG. 4 . 
         FIG. 6  shows the device of  FIG. 4  in longitudinal section taken along lines  6 - 6  in  FIG. 4 . 
         FIG. 7  is an enlarged view of the woven filament structure taken from the encircled portion  7  shown in  FIG. 5 . 
         FIG. 8  is an enlarged view of the woven filament structure taken from the encircled portion  8  shown in  FIG. 6 . 
         FIG. 9  is a proximal end view of the device of  FIG. 3 . 
         FIG. 10  is a transverse sectional view of a proximal hub portion of the device in  FIG. 6  indicated by lines  10 - 10  in  FIG. 6 . 
         FIG. 11  is an elevation view in partial section of a distal end of a delivery catheter with the device for treatment of a patient&#39;s vasculature of  FIG. 3  disposed therein in a collapsed constrained state. 
         FIG. 12  is an elevation view of a distal portion of a delivery device or actuator showing some internal structure of the device. 
         FIG. 13  is an elevation view of the delivery device of  FIG. 12  with the addition of some tubular elements over the internal structures. 
         FIG. 14  is an elevation view of the distal portion of the delivery device of  FIG. 13  with an outer coil and marker in place. 
         FIG. 15  is an elevation view of a proximal portion of the delivery device. 
         FIG. 16  illustrates an embodiment of a filament configuration for a device for treatment of a patient&#39;s vasculature. 
         FIG. 17  is a schematic view of a patient being accessed by an introducer sheath, a microcatheter and a device for treatment of a patient&#39;s vasculature releasably secured to a distal end of a delivery device or actuator. 
         FIG. 18  is a sectional view of a terminal aneurysm. 
         FIG. 19  is a sectional view of an aneurysm. 
         FIG. 20  is a schematic view in section of an aneurysm showing perpendicular arrows which indicate interior nominal longitudinal and transverse dimensions of the aneurysm. 
         FIG. 21  is a schematic view in section of the aneurysm of  FIG. 20  with a dashed outline of a device for treatment of a patient&#39;s vasculature in a relaxed unconstrained state that extends transversely outside of the walls of the aneurysm. 
         FIG. 22  is a schematic view in section of an outline of a device represented by the dashed line in  FIG. 21  in a deployed and partially constrained state within the aneurysm. 
         FIGS. 23-26  show a deployment sequence of a device for treatment of a patient&#39;s vasculature. 
         FIG. 27  is an elevation view in partial section of an embodiment of a device for treatment of a patient&#39;s vasculature deployed within an aneurysm at a tilted angle. 
         FIG. 28  is an elevation view in partial section of an embodiment of a device for treatment of a patient&#39;s vasculature deployed within an irregularly shaped aneurysm. 
         FIG. 29  shows an elevation view in section of a device for treatment of a patient&#39;s vasculature deployed within a vascular defect aneurysm. 
         FIG. 30  shows a proximal perspective view of an embodiment of a device for treatment of a patient&#39;s vasculature with a sealing zone embodiment indicated by a set of dashed lines. 
         FIGS. 31-35  illustrate various different embodiments of braiding patterns that may be used for permeable shells of devices for treatment of a patient&#39;s vasculature. 
         FIG. 36  illustrates a device for treatment of a patient&#39;s vasculature that includes non-structural fibers in the permeable shell structure of the device. 
         FIG. 37  is an enlarged view of non-structural fibers woven into filaments of a permeable shell structure. 
         FIG. 38  is an elevation view of a mandrel used for manufacture of a braided tubular member for construction of an embodiment of a device for treatment of a patient&#39;s vasculature with the initiation of the braiding process shown. 
         FIG. 39  is an elevation view of a braiding process for a braided tubular member used for manufacture of a device. 
         FIG. 40  is an elevation view in partial section of an embodiment of a fixture for heat setting a braided tubular member for manufacture of a device for treatment of a patient&#39;s vasculature. 
         FIG. 41  is an elevation view in partial section of an embodiment of a fixture for heat setting a braided tubular member for manufacture of a device for treatment of a patient&#39;s vasculature. 
         FIG. 42  is an elevation view in section of a device for treatment of a patient&#39;s vasculature. 
         FIG. 43  is a transverse sectional view of the device in  FIG. 42  indicated by lines  7 - 7  in  FIG. 42 . 
         FIGS. 43A-E  illustrate various embodiments of filament configurations for the device for treatment of a patient&#39;s vasculature. 
     
    
    
     DETAILED DESCRIPTION 
     Discussed herein are devices and methods for the treatment of vascular defects that are suitable for minimally invasive deployment within a patient&#39;s vasculature, and particularly, within the cerebral vasculature of a patient. For such embodiments to be safely and effectively delivered to a desired treatment site and effectively deployed, some device embodiments may be configured for collapse to a low profile constrained state with a transverse dimension suitable for delivery through an inner lumen of a microcatheter and deployment from a distal end thereof. Embodiments of these devices may also maintain a clinically effective configuration with sufficient mechanical integrity once deployed so as to withstand dynamic forces within a patient&#39;s vasculature over time that may otherwise result in compaction of a deployed device. It may also be desirable for some device embodiments to acutely occlude a vascular defect of a patient during the course of a procedure in order to provide more immediate feedback regarding success of the treatment to a treating physician. 
     Some embodiments are particularly useful for the treatment of cerebral aneurysms by reconstructing a vascular wall so as to wholly or partially isolate a vascular defect from a patient&#39;s blood flow. Some embodiments may be configured to be deployed within a vascular defect to facilitate reconstruction, bridging of a vessel wall or both in order to treat the vascular defect. For some of these embodiments, the permeable shell of the device may be configured to anchor or fix the permeable shell in a clinically beneficial position. For some embodiments, the device may be disposed in whole or in part within the vascular defect in order to anchor or fix the device with respect to the vascular structure or defect. The permeable shell may be configured to span an opening, neck or other portion of a vascular defect in order to isolate the vascular defect, or a portion thereof, from the patient&#39;s nominal vascular system in order allow the defect to heal or to otherwise minimize the risk of the defect to the patient&#39;s health. 
     For some or all of the embodiments of devices for treatment of a patient&#39;s vasculature discussed herein, the permeable shell may be configured to allow some initial perfusion of blood through the permeable shell. The porosity of the permeable shell may be configured to sufficiently isolate the vascular defect so as to promote healing and isolation of the defect, but allow sufficient initial flow through the permeable shell so as to reduce or otherwise minimize the mechanical force exerted on the membrane the dynamic flow of blood or other fluids within the vasculature against the device. For some embodiments of devices for treatment of a patient&#39;s vasculature, only a portion of the permeable shell that spans the opening or neck of the vascular defect, sometimes referred to as a defect spanning portion, need be permeable and/or conducive to thrombus formation in a patient&#39;s bloodstream. For such embodiments, that portion of the device that does not span an opening or neck of the vascular defect may be substantially non-permeable or completely permeable with a pore or opening configuration that is too large to effectively promote thrombus formation. 
     In general, it may be desirable in some cases to use a hollow, thin walled device with a permeable shell of resilient material that may be constrained to a low profile for delivery within a patient. Such a device may also be configured to expand radially outward upon removal of the constraint such that the shell of the device assumes a larger volume and fills or otherwise occludes a vascular defect within which it is deployed. The outward radial expansion of the shell may serve to engage some or all of an inner surface of the vascular defect whereby mechanical friction between an outer surface of the permeable shell of the device and the inside surface of the vascular defect effectively anchors the device within the vascular defect. Some embodiments of such a device may also be partially or wholly mechanically captured within a cavity of a vascular defect, particularly where the defect has a narrow neck portion with a larger interior volume. In order to achieve a low profile and volume for delivery and be capable of a high ratio of expansion by volume, some device embodiments include a matrix of woven or braided filaments that are coupled together by the interwoven structure so as to form a self-expanding permeable shell having a pore or opening pattern between couplings or intersections of the filaments that is substantially regularly spaced and stable, while still allowing for conformity and volumetric constraint. 
     As used herein, the terms woven and braided are used interchangeably to mean any form of interlacing of filaments to form a mesh structure. In the textile and other industries, these terms may have different or more specific meanings depending on the product or application such as whether an article is made in a sheet or cylindrical form. For purposes of the present disclosure, these terms are used interchangeably. 
     For some embodiments, three factors may be critical for a woven or braided wire occlusion device for treatment of a patient&#39;s vasculature that can achieve a desired clinical outcome in the endovascular treatment of cerebral aneurysms. We have found that for effective use in some applications, it may be desirable for the implant device to have sufficient radial stiffness for stability, limited pore size for near-complete acute (intra-procedural) occlusion and a collapsed profile which is small enough to allow insertion through an inner lumen of a microcatheter. A device with a radial stiffness below a certain threshold may be unstable and may be at higher risk of embolization in some cases. Larger pores between filament intersections in a braided or woven structure may not generate thrombus and occlude a vascular defect in an acute setting and thus may not give a treating physician or health professional such clinical feedback that the flow disruption will lead to a complete and lasting occlusion of the vascular defect being treated. Delivery of a device for treatment of a patient&#39;s vasculature through a standard microcatheter may be highly desirable to allow access through the tortuous cerebral vasculature in the manner that a treating physician is accustomed. 
     For some embodiments, it may be desirable to use filaments having two or more different diameters or transverse dimensions to form a permeable shell in order to produce a desired configuration as discussed in more detail below. The radial stiffness of a two-filament (two different diameters) woven device may be expressed as a function of the number of filaments and their diameters, as follows: 
         S   radial =(1.2×10 6   lbf/D   4 )( N   l   d   l   4   +N   s   d   s   4 )
 
     where S radial  is the radial stiffness in pounds force (lbf),
         D is the Device diameter (transverse dimension),   N l  is the number of large filaments,   N s  is the number of small filaments,   d l  is the diameter of the large filaments in inches, and   d s  is the diameter of the small filaments in inches.       

     Using this expression, the radial stiffness, S radial  may be between about 0.014 and 0.284 lbf force for some embodiments of particular clinical value. 
     The maximum pore size in a portion of a device that spans a neck or opening of a vascular defect desirable for some useful embodiments of a woven wire device for treatment of a patient&#39;s vasculature may be expressed as a function of the total number of all filaments, filament diameter and the device diameter. The difference between filament sizes where two or more filament diameters or transverse dimensions are used may be ignored in some cases for devices where the filament size(s) are very small compared to the device dimensions. For a two-filament device, the smallest filament diameter may be used for the calculation. Thus, the maximum pore size for such embodiments may be expressed as follows: 
         p   max =(1.7/ N   T )(π D −( N   T   d   w /2))
         where P max  is the average pore size,   D is the Device diameter (transverse dimension),   N T  is the total number of all filaments, and   d w  is the diameter of the filaments (smallest) in inches.       

     Using this expression, the maximum pore size, P max , of a portion of a device that spans an opening of a vascular defect or neck, or any other suitable portion of a device, may be less than about 0.016 inches or about 400 microns for some embodiments. In some embodiments the maximum pore size for a defect spanning portion or any other suitable portion of a device may be less than about 0.012 inches or about 300 microns. 
     The collapsed profile of a two-filament (profile having two different filament diameters) woven filament device may be expressed as the function: 
         P   c =1.48(( N   l   d   l   2   +N   s   d   s   2 )) 1/2            where P c  is the collapsed profile of the device,   N l  is the number of large filaments,   N s  is the number of small filaments,   d l  is the diameter of the large filaments in inches, and   d s  is the diameter of the small filaments in inches.       
     Using this expression, the collapsed profile P c  may be less than about 1.0 mm for some embodiments of particular clinical value. 
     In some embodiments of particular clinical value, the device may be constructed so as to have all three factors (S radial , P max  and P c ) above within the ranges discussed above; S radial  between about 0.014 lbf and 0.284 lbf, P max  less than about 300 microns and P c  less than about 1.0 mm, simultaneously. In some such embodiments, the device may be made to include about 70 filaments to about 300 filaments. In some cases, the filaments may have an outer transverse dimension or diameter of about 0.0004 inches to about 0.002 inches. 
     As has been discussed, some embodiments of devices for treatment of a patient&#39;s vasculature call for sizing the device which approximates (or with some over-sizing) the vascular site dimensions to fill the vascular site. One might assume that scaling of a device to larger dimensions and using larger filaments would suffice for such larger embodiments of a device. However, for the treatment of brain aneurysms, the diameter or profile of the radially collapsed device is limited by the catheter sizes that can be effectively navigated within the small, tortuous vessels of the brain. Further, as a device is made larger with a given or fixed number of resilient filaments having a given size or thickness, the pores or openings between junctions of the filaments are correspondingly larger. In addition, for a given filament size the flexural modulus or stiffness of the filaments and thus the structure decrease with increasing device dimension. Flexural modulus may be defined as the ratio of stress to strain. Thus, a device may be considered to have a high flexural modulus or be stiff if the strain (deflection) is low under a given force. A stiff device may also be said to have low compliance. 
     To properly configure larger size devices for treatment of a patient&#39;s vasculature, it may be useful to model the force on a device when the device is deployed into a vascular site or defect, such as a blood vessel or aneurysm, that has a diameter or transverse dimension that is smaller than a nominal diameter or transverse dimension of the device in a relaxed unconstrained state. As discussed, it may be advisable to “over-size” the device in some cases so that there is a residual force between an outside surface of the device and an inside surface of the vascular wall. The inward radial force on a device  10  that results from over-sizing is illustrated schematically in  FIG. 1  with the arrows  12  in the figure representing the inward radial force. As shown in  FIG. 2 , these compressive forces on the filaments  14  of the device in  FIG. 1  can be modeled as a simply supported beam  16  with a distributed load or force as show by the arrows  18  in the figure. It can be seen from the equation below for the deflection of a beam with two simple supports  20  and a distributed load that the deflection is a function of the length, L to the 4 th  power: 
       Deflection of Beam=5 FL   4 /384 El            where F=force,   L=length of beam,   E=Young&#39;s Modulus, and   l=moment of inertia.       
     Thus, as the size of the device increases and L increases, the compliance increases substantially. Accordingly, an outward radial force exerted by an outside surface of the filaments  14  of the device  10  against a constraining force when inserted into a vascular site such as blood vessel or aneurysm is lower for a given amount of device compression or over-sizing. This force may be important in some applications to assure device stability and to reduce the risk of migration of the device and potential distal embolization. 
     In some embodiments, a combination of small and large filament sizes may be utilized to make a device with a desired radial compliance and yet have a collapsed profile which is configured to fit through an inner lumen of commonly used microcatheters. A device fabricated with even a small number of relatively large filaments  14  can provide reduced radial compliance (or increased stiffness) compared to a device made with all small filaments. Even a relatively small number of larger filaments may provide a substantial increase in bending stiffness due to change in the moment of Inertia that results from an increase in diameter without increasing the total cross sectional area of the filaments. The moment of inertia (I) of a round wire or filament may be defined by the equation: 
         I=πd   4 /64         where d is the diameter of the wire or filament.       
     Since the moment of inertia is a function of filament diameter to the fourth power, a small change in the diameter greatly increases the moment of inertia. Thus, a small change in filament size can have substantial impact on the deflection at a given load and thus the compliance of the device. 
     Thus, the stiffness can be increased by a significant amount without a large increase in the cross sectional area of a collapsed profile of the device  10 . This may be particularly important as device embodiments are made larger to treat large aneurysms. While large cerebral aneurysms may be relatively rare, they present an important therapeutic challenge as some embolic devices currently available to physicians have relatively poor results compared to smaller aneurysms. 
     As such, some embodiments of devices for treatment of a patient&#39;s vasculature may be formed using a combination of filaments  14  with a number of different diameters such as 2, 3, 4, 5 or more different diameters or transverse dimensions. In device embodiments where filaments with two different diameters are used, some larger filament embodiments may have a transverse dimension of about 0.001 inches to about 0.004 inches and some small filament embodiments may have a transverse dimension or diameter of about 0.0004 inches and about 0.0015 inches, more specifically, about 0.0004 inches to about 0.001 inches. The ratio of the number of large filaments to the number of small filaments may be between about 2 and 12 and may also be between about 4 and 8. In some embodiments, the difference in diameter or transverse dimension between the larger and smaller filaments may be less than about 0.004 inches, more specifically, less than about 0.0035 inches, and even more specifically, less than about 0.002 inches. 
     As discussed above, device embodiments  10  for treatment of a patient&#39;s vasculature may include a plurality of wires, fibers, threads, tubes or other filamentary elements that form a structure that serves as a permeable shell. For some embodiments, a globular shape may be formed from such filaments by connecting or securing the ends of a tubular braided structure. For such embodiments, the density of a braided or woven structure may inherently increase at or near the ends where the wires or filaments  14  are brought together and decrease at or near a middle portion  30  disposed between a proximal end  32  and distal end  34  of the permeable shell  40 . For some embodiments, an end or any other suitable portion of a permeable shell  40  may be positioned in an opening or neck of a vascular defect such as an aneurysm for treatment. As such, a braided or woven filamentary device with a permeable shell may not require the addition of a separate defect spanning structure having properties different from that of a nominal portion of the permeable shell to achieve hemostasis and occlusion of the vascular defect. Such a filamentary device may be fabricated by braiding, weaving or other suitable filament fabrication techniques. Such device embodiments may be shape set into a variety of three dimensional shapes such as discussed herein. 
     Referring to  FIGS. 3-10 , an embodiment of a device for treatment of a patient&#39;s vasculature  10  is shown. The device  10  includes a self-expanding resilient permeable shell  40  having a proximal end  32 , a distal end  34 , a longitudinal axis  46  and further comprising a plurality of elongate resilient filaments  14  including large filaments  48  and small filaments  50  of at least two different transverse dimensions as shown in more detail in  FIGS. 5,7 and 18 . The filaments  14  have a woven structure and are secured relative to each other at proximal ends  60  and distal ends  62  thereof. The permeable shell  40  of the device has a radially constrained elongated state configured for delivery within a microcatheter  61 , as shown in  FIG. 11 , with the thin woven filaments  14  extending longitudinally from the proximal end  42  to the distal end  44  radially adjacent each other along a length of the filaments. 
     As shown in  FIGS. 3-6 , the permeable shell  40  also has an expanded relaxed state with a globular and longitudinally shortened configuration relative to the radially constrained state. In the expanded state, the woven filaments  14  form the self-expanding resilient permeable shell  40  in a smooth path radially expanded from a longitudinal axis  46  of the device between the proximal end  32  and distal end  34 . The woven structure of the filaments  14  includes a plurality of openings  64  in the permeable shell  40  formed between the woven filaments. For some embodiments, the largest of said openings  64  may be configured to allow blood flow through the openings only at a velocity below a thrombotic threshold velocity. Thrombotic threshold velocity has been defined, at least by some, as the time-average velocity at which more than 50% of a vascular graft surface is covered by thrombus when deployed within a patient&#39;s vasculature. In the context of aneurysm occlusion, a slightly different threshold may be appropriate. Accordingly, the thrombotic threshold velocity as used herein shall include the velocity at which clotting occurs within or on a device, such as device  10 , deployed within a patient&#39;s vasculature such that blood flow into a vascular defect treated by the device is substantially blocked in less than about 1 hour or otherwise during the treatment procedure. The blockage of blood flow into the vascular defect may be indicated in some cases by minimal contrast agent entering the vascular defect after a sufficient amount of contrast agent has been injected into the patient&#39;s vasculature upstream of the implant site and visualized as it dissipates from that site. Such sustained blockage of flow within less than about 1 hour or during the duration of the implantation procedure may also be referred to as acute occlusion of the vascular defect. 
     As such, once the device  10  is deployed, any blood flowing through the permeable shell may be slowed to a velocity below the thrombotic threshold velocity and thrombus will begin to form on and around the openings in the permeable shell  40 . Ultimately, this process may be configured to produce acute occlusion of the vascular defect within which the device  10  is deployed. For some embodiments, at least the distal end of the permeable shell  40  may have a reverse bend in an everted configuration such that the secured distal ends  62  of the filaments  14  are withdrawn axially within the nominal permeable shell structure or contour in the expanded state. For some embodiments, the proximal end of the permeable shell further includes a reverse bend in an everted configuration such that the secured proximal ends  60  of the filaments  14  are withdrawn axially within the nominal permeable shell structure  40  in the expanded state. As used herein, the term everted may include a structure that is everted, partially everted and/or recessed with a reverse bend as shown in the device embodiment of  FIGS. 3-6 . For such embodiments, the ends  60  and  62  of the filaments  14  of the permeable shell or hub structure disposed around the ends may be withdrawn within or below the globular shaped periphery of the permeable shell of the device. 
     The elongate resilient filaments  14  of the permeable shell  40  may be secured relative to each other at proximal ends  60  and distal ends  62  thereof by one or more methods including welding, soldering, adhesive bonding, epoxy bonding or the like. In addition to the ends of the filaments being secured together, a distal hub  66  may also be secured to the distal ends  62  of the thin filaments  14  of the permeable shell  40  and a proximal hub  68  secured to the proximal ends  60  of the thin filaments  14  of the permeable shell  40 . The proximal hub  68  may include a cylindrical member that extends proximally beyond the proximal ends  60  of the thin filaments so as to form a cavity  70  within a proximal portion of the proximal hub  68 . The proximal cavity  70  may be used for holding adhesives such as epoxy, solder or any other suitable bonding agent for securing an elongate detachment tether  72  that may in turn be detachably secured to a delivery apparatus such as is shown in  FIGS. 11-15 . 
     For some embodiments, the elongate resilient filaments  14  of the permeable shell  40  may have a transverse cross section that is substantially round in shape and be made from a superelastic material that may also be a shape memory metal. The shape memory metal of the filaments of the permeable shell  40  may be heat set in the globular configuration of the relaxed expanded state as shown in  FIGS. 3-6 . Suitable superelastic shape memory metals may include alloys such as NiTi alloy and the like. The superelastic properties of such alloys may be useful in providing the resilient properties to the elongate filaments  14  so that they can be heat set in the globular form shown, fully constrained for delivery within an inner lumen of a microcatheter and then released to self expand back to substantially the original heat set shape of the globular configuration upon deployment within a patient&#39;s body. 
     The device  10  may have an everted filamentary structure with a permeable shell  40  having a proximal end  32  and a distal end  34  in an expanded relaxed state. The permeable shell  40  has a substantially enclosed configuration for the embodiments shown. Some or all of the permeable shell  40  of the device  10  may be configured to substantially block or impede fluid flow or pressure into a vascular defect or otherwise isolate the vascular defect over some period of time after the device is deployed in an expanded state. The permeable shell  40  and device  10  generally also has a low profile, radially constrained state, as shown in  FIG. 11 , with an elongated tubular or cylindrical configuration that includes the proximal end  32 , the distal end  34  and a longitudinal axis  46 . While in the radially constrained state, the elongate flexible filaments  14  of the permeable shell  40  may be disposed substantially parallel and in close lateral proximity to each other between the proximal end and distal end forming a substantially tubular or compressed cylindrical configuration. 
     Proximal ends  60  of at least some of the filaments  14  of the permeable shell  40  may be secured to the proximal hub  68  and distal ends  62  of at least some of the filaments  14  of the permeable shell  40  are secured to the distal hub  66 , with the proximal hub  68  and distal hub  66  being disposed substantially concentric to the longitudinal axis  46  as shown in  FIG. 4 . The ends of the filaments  14  may be secured to the respective hubs  66  and  68  by any of the methods discussed above with respect to securement of the filament ends to each other, including the use of adhesives, solder, welding and the like. A middle portion  30  of the permeable shell  40  may have a first transverse dimension with a low profile suitable for delivery from a microcatheter as shown in  FIG. 11 . Radial constraint on the device  10  may be applied by an inside surface of the inner lumen of a microcatheter, such as the distal end portion of the microcatheter  61  shown, or it may be applied by any other suitable mechanism that may be released in a controllable manner upon ejection of the device  10  from the distal end of the catheter. In  FIG. 11  a proximal end or hub  68  of the device  10  is secured to a distal end of an elongate delivery apparatus  110  of a delivery system  112  disposed at the proximal hub  68  of the device  10 . 
     Some device embodiments  10  having a braided or woven filamentary structure may be formed using about 10 filaments to about 300 filaments  14 , more specifically, about 10 filaments to about 100 filaments  14 , and even more specifically, about 60 filaments to about 80 filaments  14 . Some embodiments of a permeable shell  40  may include about 70 filaments to about 300 filaments extending from the proximal end  32  to the distal end  34 , more specifically, about 100 filaments to about 200 filaments extending from the proximal end  32  to the distal end  34 . For some embodiments, the filaments  14  may have a transverse dimension or diameter of about 0.0008 inches to about 0.004 inches. The elongate resilient filaments  14  in some cases may have an outer transverse dimension or diameter of about 0.0005 inch to about 0.005 inch, more specifically, about 0.001 inch to about 0.003 inch, and in some cases about 0.0004 inches to about 0.002 inches. For some device embodiments  10  that include filaments  14  of different sizes, the large filaments  48  of the permeable shell  40  may have a transverse dimension or diameter that is about 0.001 inches to about 0.004 inches and the small filaments  50  may have a transverse dimension or diameter of about 0.0004 inches to about 0.0015 inches, more specifically, about 0.0004 inches to about 0.001 inches. In addition, a difference in transverse dimension or diameter between the small filaments  50  and the large filaments  48  may be less than about 0.004 inches, more specifically, less than about 0.0035 inches, and even more specifically, less than about 0.002 inches. For embodiments of permeable shells  40  that include filaments  14  of different sizes, the number of small filaments  50  of the permeable shell  40  relative to the number of large filaments  48  of the permeable shell  40  may be about 2 to 1 to about 15 to 1, more specifically, about 2 to 1 to about 12 to 1, and even more specifically, about 4 to 1 to about 8 to 1. 
     The expanded relaxed state of the permeable shell  40 , as shown in  FIG. 4 , has an axially shortened configuration relative to the constrained state such that the proximal hub  68  is disposed closer to the distal hub  66  than in the constrained state. Both hubs  66  and  68  are disposed substantially concentric to the longitudinal axis  46  of the device and each filamentary element  14  forms a smooth arc between the proximal and distal hubs  66  and  68  with a reverse bend at each end. A longitudinal spacing between the proximal and distal hubs  66  and  68  of the permeable shell  40  in a deployed relaxed state may be about 25 percent to about 75 percent of the longitudinal spacing between the proximal and distal hubs  66  and  68  in the constrained cylindrical state, for some embodiments. The arc of the filaments  14  between the proximal and distal ends  32  and  34  may be configured such that a middle portion of each filament  14  has a second transverse dimension substantially greater than the first transverse dimension. 
     For some embodiments, the permeable shell  40  may have a first transverse dimension in a collapsed radially constrained state of about 0.2 mm to about 2 mm and a second transverse dimension in a relaxed expanded state of about 4 mm to about 30 mm. For some embodiments, the second transverse dimension of the permeable shell  40  in an expanded state may be about 2 times to about 150 times the first transverse dimension, more specifically, about 10 times to about 25 times the first or constrained transverse dimension. A longitudinal spacing between the proximal end  32  and distal end  34  of the permeable shell  40  in the relaxed expanded state may be about 25% percent to about 75% percent of the spacing between the proximal end  32  and distal end  34  in the constrained cylindrical state. For some embodiments, a major transverse dimension of the permeable shell  40  in a relaxed expanded state may be about 4 mm to about 30 mm, more specifically, about 9 mm to about 15 mm, and even more specifically, about 4 mm to about 8 mm. 
     An arced portion of the filaments  14  of the permeable shell  40  may have a sinusoidal-like shape with a first or outer radius  88  and a second or inner radius  90  near the ends of the permeable shell  40  as shown in  FIG. 6 . This sinusoid-like or multiple curve shape may provide a concavity in the proximal end  32  that may reduce an obstruction of flow in a parent vessel adjacent a vascular defect. For some embodiments, the first radius  88  and second radius  90  of the permeable shell  40  may be between about 0.12 mm to about 3 mm. For some embodiments, the distance between the proximal end  32  and distal end  34  may be less than about 60% of the overall length of the permeable shell  40  for some embodiments. Such a configuration may allow for the distal end  34  to flex downward toward the proximal end  32  when the device  10  meets resistance at the distal end  34  and thus may provide longitudinal conformance. The filaments  14  may be shaped in some embodiments such that there are no portions that are without curvature over a distance of more than about 2 mm. Thus, for some embodiments, each filament  14  may have a substantially continuous curvature. This substantially continuous curvature may provide smooth deployment and may reduce the risk of vessel perforation. For some embodiments, one of the ends  32  or  34  may be retracted or everted to a greater extent than the other so as to be more longitudinally or axially conformal than the other end. 
     The first radius  88  and second radius  90  of the permeable shell  40  may be between about 0.12 mm to about 3 mm for some embodiments. For some embodiments, the distance between the proximal end  32  and distal end  34  may be more than about 60% of the overall length of the expanded permeable shell  40 . Thus, the largest longitudinal distance between the inner surfaces may be about 60% to about 90% of the longitudinal length of the outer surfaces or the overall length of device  10 . A gap between the hubs  66  and  68  at the proximal end  32  and distal end  34  may allow for the distal hub  66  to flex downward toward the proximal hub  68  when the device  10  meets resistance at the distal end and thus provides longitudinal conformance. The filaments  14  may be shaped such that there are no portions that are without curvature over a distance of more than about 2 mm. Thus, for some embodiments, each filament  14  may have a substantially continuous curvature. This substantially continuous curvature may provide smooth deployment and may reduce the risk of vessel perforation. The distal end  34  may be retracted or everted to a greater extent than the proximal end  32  such that the distal end portion of the permeable shell  40  may be more radially conformal than the proximal end portion. Conformability of a distal end portion may provide better device conformance to irregular shaped aneurysms or other vascular defects. A convex surface of the device may flex inward forming a concave surface to conform to curvature of a vascular site. 
       FIG. 10  shows an enlarged view of the filaments  14  disposed within a proximal hub  68  of the device  10  with the filaments  14  of two different sizes constrained and tightly packed by an outer ring of the proximal hub  68 . The tether member  72  may optionally be disposed within a middle portion of the filaments  14  or within the cavity  70  of the proximal hub  68  proximal of the proximal ends  60  of the filaments  14  as shown in  FIG. 6 . The distal end of the tether  72  may be secured with a knot  92  formed in the distal end thereof which is mechanically captured in the cavity  70  of the proximal hub  68  formed by a proximal shoulder portion  94  of the proximal hub  68 . The knotted distal end  92  of the tether  72  may also be secured by bonding or potting of the distal end of the tether  72  within the cavity  70  and optionally amongst the proximal ends  60  of the filaments  14  with mechanical compression, adhesive bonding, welding, soldering, brazing or the like. The tether embodiment  72  shown in  FIG. 6  has a knotted distal end  92  potted in the cavity of the proximal hub  68  with an adhesive. Such a tether  72  may be a dissolvable, severable or releasable tether that may be part of a delivery apparatus  110  used to deploy the device  10  as shown in  FIG. 11  and  FIGS. 23-26 .  FIG. 10  also shows the large filaments  48  and small filaments  50  disposed within and constrained by the proximal hub  68  which may be configured to secure the large and small filaments  48  and  50  in place relative to each other within the outer ring of the proximal hub  68 . 
       FIGS. 7 and 8  illustrate some configuration embodiments of braided filaments  14  of a permeable shell  40  of the device  10  for treatment of a patient&#39;s vasculature. The braid structure in each embodiment is shown with a circular shape  100  disposed within a pore  64  of a woven or braided structure with the circular shape  100  making contact with each adjacent filament segment. The pore opening size may be determined at least in part by the size of the filament elements  14  of the braid, the angle overlapping filaments make relative to each other and the picks per inch of the braid structure. For some embodiments, the cells or openings  64  may have an elongated substantially diamond shape as shown in  FIG. 7 , and the pores or openings  64  of the permeable shell  40  may have a substantially more square shape toward a middle portion  30  of the device  10 , as shown in  FIG. 8 . The diamond shaped pores or openings  64  may have a length substantially greater than the width particularly near the hubs  66  and  68 . In some embodiments, the ratio of diamond shaped pore or opening length to width may exceed a ratio of 3 to 1 for some cells. The diamond-shaped openings  64  may have lengths greater than the width thus having an aspect ratio, defined as Length/Width of greater than 1. The openings  64  near the hubs  66  and  68  may have substantially larger aspect ratios than those farther from the hubs as shown in  FIG. 7 . The aspect ratio of openings  64  adjacent the hubs may be greater than about 4 to 1. The aspect ratio of openings  64  near the largest diameter may be between about 0.75 to 1 and about 2 to 1 for some embodiments. For some embodiments, the aspect ratio of the openings  64  in the permeable shell  40  may be about 0.5 to 1 to about 2 to 1. 
     The pore size defined by the largest circular shapes  100  that may be disposed within openings  64  of the braided structure of the permeable shell  40  without displacing or distorting the filaments  14  surrounding the opening  64  may range in size from about 0.005 inches to about 0.01 inches, more specifically, about 0.006 inches to about 0.009 inches, even more specifically, about 0.007 inches to about 0.008 inches for some embodiments. In addition, at least some of the openings  64  formed between adjacent filaments  14  of the permeable shell  40  of the device  10  may be configured to allow blood flow through the openings  64  only at a velocity below a thrombotic threshold velocity. For some embodiments, the largest openings  64  in the permeable shell structure  40  may be configured to allow blood flow through the openings  64  only at a velocity below a thrombotic threshold velocity. As discussed above, the pore size may be less than about 0.016 inches, more specifically, less than about 0.012 inches for some embodiments. For some embodiments, the openings  64  formed between adjacent filaments  14  may be about 0.005 inches to about 0.04 inches. 
     Referring to  FIGS. 12-15 , a delivery apparatus embodiment  110  of the delivery system  112  of  FIG. 11  is shown in more detail. The apparatus  110  includes an elongate core wire  114  that extends from a proximal end  116  of the apparatus  110  to a distal section  118  of the apparatus  110  as shown in  FIG. 12 . The core wire  114  is configured to provide sufficient column strength to push a constrained device  10  for treatment of a patient&#39;s vasculature through an inner lumen  120  of the microcatheter  61  of the delivery system  112  as shown in  FIG. 11 . The core wire  114  also has sufficient tensile strength to withdraw or proximally retract the device  10  from a position outside the microcatheter  61  and axially within the inner lumen  120  of the microcatheter  61 . The tether  72  that extends proximally from the proximal hub  68  is secured to the distal end of the core wire  114  with a length of shrinkable tubing  122  that is disposed over a portion of the tether  72  and a distal section of the core wire  114  and shrunk over both as shown in  FIG. 13 , although any other suitable means of securement may be used. 
     A heater coil  124  electrically coupled to a first conductor  126  and a second conductor  128  is disposed over a distal most portion of the tether  72 . The heater coil  124  may also be covered with a length of polymer tubing  130  disposed over the heater coil  124  distal of the heat shrink tubing  122  that serves to act as a heat shield and minimizes the leakage of heat from the heater coil  124  into the environment, such as the patient&#39;s blood stream, around the delivery apparatus  110 . Once the heat shrink tubing  122  and insulating polymer tubing  130  have been secured to the distal section  118  of the apparatus  110 , the proximal portion of the tether  72  disposed proximal of the heat shrink tubing  122  may be trimmed as shown in FIG.  13 . An over coil  132  that extends from a distal end  134  of the delivery apparatus  110  to a proximal section  136  of the apparatus  110  may then be disposed over the heater coil  124 , core wire  114 , tether  72 , first conductor  126  and second conductor  128  to hold these elements together, produce a low friction outer surface and maintain a desired flexibility of the delivery apparatus  110 . The proximal section  136  of the apparatus  110  includes the proximal terminus of the over coil  132  which is disposed distal of a first contact  138  and second contact  140  which are circumferentially disposed about the proximal section  136  of the core wire  114 , insulated therefrom, and electrically coupled to the first conductor  126  and second conductor  128 , respectively as shown in  FIG. 15 . 
     The heater coil  124  may be configured to receive electric current supplied through the first conductor  126  and second conductor  128  from an electrical energy source  142  coupled to the first contact  138  and second contact  140  at the proximal section  136  of the apparatus  110 . The electrical current passed through the heater coil  124  heats the heater coil to a temperature above the melting point of the tether material  72  so as to melt the tether  72  and sever it upon deployment of the device  10 . 
     Embodiments of the delivery apparatus  110  may generally have a length greater than the overall length of a microcatheter  61  to be used for the delivery system  112 . This relationship allows the delivery apparatus  110  to extend, along with the device  10  secured to the distal end thereof, from the distal port of the inner lumen  120  of the microcatheter  61  while having sufficient length extending from a proximal end  150  of the microcatheter  61 , shown in  FIG. 17  discussed below, to enable manipulation thereof by a physician. For some embodiments, the length of the delivery apparatus  110  may be about 170 cm to about 200 cm. The core wire  114  may be made from any suitable high strength material such as stainless steel, NiTi alloy, or the like. Embodiments of the core wire  114  may have an outer diameter or transverse dimension of about 0.010 inch to about 0.015 inch. The over coil  132  may have an outer diameter or transverse dimension of about 0.018 inch to about 0.03 inch. Although the apparatus embodiment  110  shown in  FIGS. 12-15  is activated by electrical energy passed through a conductor pair, a similar configuration that utilizes light energy passed through a fiber optic or any other suitable arrangement could be used to remotely heat a distal heating member or element such as the heater coil  124  to sever the distal portion of the tether  72 . In addition, other delivery apparatus embodiments are discussed and incorporated herein that may also be used for any of the device embodiments  10  for treatment of a patient&#39;s vasculature discussed herein. 
     Other delivery and positioning system embodiments may provide for the ability to rotate a device for treatment of a patient&#39;s vasculature in-vivo without translating torque along the entire length of the delivery apparatus. Some embodiments for delivery and positioning of devices  10  are described in co-owned International PCT Patent Application No. PCT/US2008/065694 incorporated above. The delivery and positioning apparatus may include a distal rotating member that allows rotational positioning of the device. The delivery and positioning apparatus may include a distal rotating member which rotates an implant in-vivo without the transmission of torque along the entire length of the apparatus. Optionally, delivery system may also rotate the implant without the transmission of torque in the intermediate portion between the proximal end and the distal rotatable end. The delivery and positioning apparatus may be releasably secured to any suitable portion of the device for treatment of a patient&#39;s vasculature. 
     Device embodiments discussed herein may be releasable from any suitable flexible, elongate delivery apparatus or actuator such as a guidewire or guidewire-like structure. The release of device embodiments from such a delivery apparatus may be activated by a thermal mechanism, as discussed above, electrolytic mechanism, hydraulic mechanism, shape memory material mechanism, or any other mechanism known in the art of endovascular implant deployment. 
     Embodiments for deployment and release of therapeutic devices, such as deployment of embolic devices or stents within the vasculature of a patient, may include connecting such a device via a releasable connection to a distal portion of a pusher or other delivery apparatus member. The therapeutic device  10  may be detachably mounted to the distal portion of the apparatus by a filamentary tether  72 , string, thread, wire, suture, fiber, or the like, which may be referred to above as the tether. The tether  72  may be in the form of a monofilament, rod, ribbon, hollow tube, or the like. Some embodiments of the tether may have a diameter or maximum thickness of between about 0.05 mm and 0.2 mm. The tether  72  may be configured to be able to withstand a maximum tensile load of between about 0.5 kg and 5 kg. For some embodiments, due to the mass of the device  10  being deployed which may be substantially greater than some embolic devices, some known detachment devices may lack sufficient tensile strength to be used for some embodiments discussed herein. As such, it may be desirable to use small very high strength fibers for some tether embodiments having a “load at break” greater than about 15 Newtons. For some embodiments, a tether made from a material known as Dyneema Purity available from Royal DSM, Heerlen, Netherlands may be used. 
     The tether  72  may be severed by the input of energy such as electric current to a heating element causing release of the therapeutic device. For some embodiments, the heating element may be a coil of wire with high electrical resistivity such as a platinum-tungsten alloy. The tether member may pass through or be positioned adjacent the heater element. The heater may be contained substantially within the distal portion of the delivery apparatus to provide thermal insulation to reduce the potential for thermal damage to the surrounding tissues during detachment. In another embodiment, current may pass through the tether which also acts as a heating element. 
     Many materials may be used to make tether embodiments  72  including polymers, metals and composites thereof. One class of materials that may be useful for tethers includes polymers such as polyolefin, polyolefin elastomer such as polyethylene, polyester (PET), polyamide (Nylon), polyurethane, polypropylene, block copolymer such as PEBAX or Hytrel, and ethylene vinyl alcohol (EVA); or rubbery materials such as silicone, latex, and Kraton. In some cases, the polymer may also be cross-linked with radiation to manipulate its tensile strength and melt temperature. Another class of materials that may be used for tether embodiment may include metals such as nickel titanium alloy (Nitinol), gold, platinum, tantalum and steel. Other materials that may be useful for tether construction includes wholly aromatic polyester polymers which are liquid crystal polymers (LCP) that may provide high performance properties and are highly inert. A commercially available LCP polymer is Vectran, which is produced by Kuraray Co. (Tokyo, Japan). The selection of the material may depend on the melting or softening temperature, the power used for detachment, and the body treatment site. The tether may be joined to the implant and/or the pusher by crimping, welding, knot tying, soldering, adhesive bonding, or other means known in the art. 
     It should be noted also that many variations of filament and proximal hub construction such as is detailed above with regard to  FIG. 10  may be used for useful embodiments of a device for treatment of a patient&#39;s vasculature  10 .  FIG. 16  shows an enlarged view in transverse cross section of a proximal hub configuration. For the embodiment shown, the filaments  14  are disposed within a proximal hub  68  or end portion of the device  10  with the filaments  14  constrained and tightly packed by an outer ring of the proximal hub  68 . A tether member  72  may be disposed within a middle portion of the filaments  14  or within a cavity of the proximal hub  68  proximal of the proximal ends  60  of the filaments  14 . Such a tether  72  may be a dissolvable, severable or releasable tether that may be part of a release apparatus as discussed above used to deploy the device. 
       FIG. 16  illustrates in transverse cross section an embodiment of a proximal hub  68  showing the configuration of filaments which may be tightly packed and radially constrained by an inside surface of the proximal hub  68 . In some embodiments, the braided or woven structure of the permeable shell  40  formed from such filaments  14  may be constructed using a large number of small filaments. The number of filaments  14  may be greater than 125 and may also be between about 80 filaments and about 180 filaments. As discussed above, the total number of filaments  14  for some embodiments may be about 70 filaments to about 300 filaments, more specifically, about 100 filaments to about 200 filaments. In some embodiments, the braided structure of the permeable shell  40  may be constructed with two or more sizes of filaments  14 . For example, the structure may have several larger filaments that provide structural support and several smaller filaments that provide the desired pore size and density and thus flow resistance to achieve a thrombotic threshold velocity in some cases. For some embodiments, small filaments  50  of the permeable shell  40  may have a transverse dimension or diameter of about 0.0006 inches to about 0.002 inches for some embodiments and about 0.0004 inches to about 0.001 inches in other embodiments. The large filaments  48  may have a transverse dimension or diameter of about 0.0015 inches to about 0.004 inches in some embodiments and about 0.001 inches to about 0.004 inches in other embodiments. The filaments  14  may be braided in a plain weave that is one under, one over structure (shown in  FIGS. 7 and 8 ) or a supplementary weave; more than one warp interlace with one or more than one weft. The pick count may be varied between about 25 and 200 picks per inch (PPI). 
     For some embodiments, the permeable shell  40  or portions thereof may be porous and may be highly permeable to liquids. In contrast to most vascular prosthesis fabrics or grafts which typically have a water permeability below 2,000 ml/min/cm 2  when measured at a pressure of 120 mmHg, the permeable shell  40  of some embodiments discussed herein may have a water permeability greater than about 2,000 ml/min/cm 2 , in some cases greater than about 2,500 ml/min/cm 2 . For some embodiments, water permeability of the permeable shell  40  or portions thereof may be between about 2,000 and 10,000 ml/min/cm 2 , more specifically, about 2,000 ml/min/cm 2  to about 15,000 ml/min/cm 2 , when measured at a pressure of 120 mmHg. 
     Device embodiments and components thereof may include metals, polymers, biologic materials and composites thereof. Suitable metals include zirconium-based alloys, cobalt-chrome alloys, nickel-titanium alloys, platinum, tantalum, stainless steel, titanium, gold, and tungsten. Potentially suitable polymers include but are not limited to acrylics, silk, silicones, polyvinyl alcohol, polypropylene, polyvinyl alcohol, polyesters (e.g. polyethylene terephthalate or PET), PolyEtherEther Ketone (PEEK), polytetrafluoroethylene (PTFE), polycarbonate urethane (PCU) and polyurethane (PU). Device embodiments may include a material that degrades or is absorbed or eroded by the body. A bioresorbable (e.g., breaks down and is absorbed by a cell, tissue, or other mechanism within the body) or bioabsorbable (similar to bioresorbable) material may be used. Alternatively, a bioerodable (e.g., erodes or degrades over time by contact with surrounding tissue fluids, through cellular activity or other physiological degradation mechanisms), biodegradable (e.g., degrades over time by enzymatic or hydrolytic action, or other mechanism in the body), or dissolvable material may be employed. Each of these terms is interpreted to be interchangeable. bioabsorbable polymer. Potentially suitable bioabsorbable materials include polylactic acid (PLA), poly(alpha-hydroxy acid) such as poly-L-lactide (PLLA), poly-D-lactide (PDLA), polyglycolide (PGA), polydioxanone, polycaprolactone, polygluconate, polylactic acid-polyethylene oxide copolymers, modified cellulose, collagen, poly(hydroxybutyrate), polyanhydride, polyphosphoester, poly(amino acids), or related copolymer materials. An absorbable composite fiber may be made by combining a reinforcement fiber made from a copolymer of about 18% glycolic acid and about 82% lactic acid with a matrix material consisting of a blend of the above copolymer with about 20% polycaprolactone (PCL). 
     In any of the suitable device embodiments  10  discussed herein, the permeable shell structure  40  may include one or more fixation elements or surfaces to facilitate fixation of the device within a blood vessel or other vascular site. The fixation elements may comprise hooks, barbs, protrusions, pores, microfeatures, texturing, bioadhesives or combinations thereof. Embodiments of the support structure may be fabricated from a tube of metal where portions are removed. The removal of material may be done by laser, electrical discharge machining (EDM), photochemical etching and traditional machining techniques. In any of the described embodiments, the support structure may be constructed with a plurality of wires, cut or etched from a sheet of a material, cut or etched from a tube or a combination thereof as in the art of vascular stent fabrication. 
     Permeable shell embodiments  40  may be formed at least in part of wire, ribbon, or other filamentary elements  14 . These filamentary elements  14  may have circular, elliptical, ovoid, square, rectangular, or triangular cross-sections. Permeable shell embodiments  40  may also be formed using conventional machining, laser cutting, electrical discharge machining (EDM) or photochemical machining (PCM). If made of a metal, it may be formed from either metallic tubes or sheet material. 
     Device embodiments  10  discussed herein may be delivered and deployed from a delivery and positioning system  112  that includes a microcatheter  61 , such as the type of microcatheter  61  that is known in the art of neurovascular navigation and therapy. Device embodiments for treatment of a patient&#39;s vasculature  10  may be elastically collapsed and restrained by a tube or other radial restraint, such as an inner lumen  120  of a microcatheter  61 , for delivery and deployment. The microcatheter  61  may generally be inserted through a small incision  152  accessing a peripheral blood vessel such as the femoral artery or brachial artery. The microcatheter  61  may be delivered or otherwise navigated to a desired treatment site  154  from a position outside the patient&#39;s body  156  over a guidewire  159  under fluoroscopy or by other suitable guiding methods. The guidewire  159  may be removed during such a procedure to allow insertion of the device  10  secured to a delivery apparatus  110  of the delivery system  112  through the inner lumen  120  of a microcatheter  61  in some cases.  FIG. 17  illustrates a schematic view of a patient  158  undergoing treatment of a vascular defect  160  as shown in  FIG. 18 . An access sheath  162  is shown disposed within either a radial artery  164  or femoral artery  166  of the patient  158  with a delivery system  112  that includes a microcatheter  61  and delivery apparatus  110  disposed within the access sheath  162 . The delivery system  112  is shown extending distally into the vasculature of the patient&#39;s brain adjacent a vascular defect  160  in the patient&#39;s brain. 
     Access to a variety of blood vessels of a patient may be established, including arteries such as the femoral artery  166 , radial artery  164 , and the like in order to achieve percutaneous access to a vascular defect  160 . In general, the patient  158  may be prepared for surgery and the access artery is exposed via a small surgical incision  152  and access to the lumen is gained using the Seldinger technique where an introducing needle is used to place a wire over which a dilator or series of dilators dilates a vessel allowing an introducer sheath  162  to be inserted into the vessel. This would allow the device to be used percutaneously. With an introducer sheath  162  in place, a guiding catheter  168  is then used to provide a safe passageway from the entry site to a region near the target site  154  to be treated. For example, in treating a site in the human brain, a guiding catheter  168  would be chosen which would extend from the entry site  152  at the femoral artery up through the large arteries extending around the heart through the aortic arch, and downstream through one of the arteries extending from the upper side of the aorta such as the carotid artery  170 . Typically, a guidewire  159  and neurovascular microcatheter  61  are then placed through the guiding catheter  168  and advanced through the patient&#39;s vasculature, until a distal end  151  of the microcatheter  61  is disposed adjacent or within the target vascular defect  160 , such as an aneurysm. Exemplary guidewires  159  for neurovascular use include the Synchro2® made by Boston Scientific and the Glidewire Gold Neuro® made by MicroVention Terumo. Typical guidewire sizes may include 0.014 inches and 0.018 inches. Once the distal end  151  of the catheter  61  is positioned at the site, often by locating its distal end through the use of radiopaque marker material and fluoroscopy, the catheter is cleared. For example, if a guidewire  159  has been used to position the microcatheter  61 , it is withdrawn from the catheter  61  and then the implant delivery apparatus  110  is advanced through the microcatheter  61 . 
     Delivery and deployment of device embodiments  10  discussed herein may be carried out by first compressing the device  10  to a radially constrained and longitudinally flexible state as shown in  FIG. 11 . The device  10  may then be delivered to a desired treatment site  154  while disposed within the microcatheter  61 , and then ejected or otherwise deployed from a distal end  151  of the microcatheter  61 . In other method embodiments, the microcatheter  61  may first be navigated to a desired treatment site  154  over a guidewire  159  or by other suitable navigation techniques. The distal end of the microcatheter  61  may be positioned such that a distal port of the microcatheter  61  is directed towards or disposed within a vascular defect  160  to be treated and the guidewire  159  withdrawn. The device  10  secured to a suitable delivery apparatus  110  may then be radially constrained, inserted into a proximal portion of the inner lumen  120  of the microcatheter  61  and distally advanced to the vascular defect  160  through the inner lumen  120 . 
     Once disposed within the vascular defect  160 , the device  10  may then allowed to assume an expanded relaxed or partially relaxed state with the permeable shell  40  of the device spanning or partially spanning a portion of the vascular defect  160  or the entire vascular defect  160 . The device  10  may also be activated by the application of an energy source to assume an expanded deployed configuration once ejected from the distal section of the microcatheter  61  for some embodiments. Once the device  10  is deployed at a desired treatment site  154 , the microcatheter  61  may then be withdrawn. 
     Some embodiments of devices for the treatment of a patient&#39;s vasculature  10  discussed herein may be directed to the treatment of specific types of defects of a patient&#39;s vasculature. For example, referring to  FIG. 18 , an aneurysm  160  commonly referred to as a terminal aneurysm is shown in section. Terminal aneurysms occur typically at bifurcations in a patient&#39;s vasculature where blood flow, indicated by the arrows  172 , from a supply vessel splits into two or more branch vessels directed away from each other. The main flow of blood from the supply vessel  174 , such as a basilar artery, sometimes impinges on the vessel where the vessel diverges and where the aneurysm sack forms. Terminal aneurysms may have a well defined neck structure where the profile of the aneurysm  160  narrows adjacent the nominal vessel profile, but other terminal aneurysm embodiments may have a less defined neck structure or no neck structure.  FIG. 19  illustrates a typical berry type aneurysm  160  in section where a portion of a wall of a nominal vessel section weakens and expands into a sack like structure ballooning away from the nominal vessel surface and profile. Some berry type aneurysms may have a well defined neck structure as shown in  FIG. 19 , but others may have a less defined neck structure or none at all.  FIG. 19  also shows some optional procedures wherein a stent  173  or other type of support has been deployed in the parent vessel  174  adjacent the aneurysm. Also, shown is embolic material  176  being deposited into the aneurysm  160  through a microcatheter  61 . Either or both of the stent  173  and embolic material  176  may be so deployed either before or after the deployment of a device for treatment of a patient&#39;s vasculature  10 . 
     Prior to delivery and deployment of a device for treatment of a patient&#39;s vasculature  10 , it may be desirable for the treating physician to choose an appropriately sized device  10  to optimize the treatment results. Some embodiments of treatment may include estimating a volume of a vascular site or defect  160  to be treated and selecting a device  10  with a volume that is substantially the same volume or slightly over-sized relative to the volume of the vascular site or defect  160 . The volume of the vascular defect  160  to be occluded may be determined using three-dimensional angiography or other similar imaging techniques along with software which calculates the volume of a selected region. The amount of over-sizing may be between about 2% and 15% of the measured volume. In some embodiments, such as a very irregular shaped aneurysm, it may be desirable to under-size the volume of the device  10 . Small lobes or “daughter aneurysms” may be excluded from the volume, defining a truncated volume which may be only partially filled by the device without affecting the outcome. A device  10  deployed within such an irregularly shaped aneurysm  160  is shown in  FIG. 28  discussed below. Such a method embodiment may also include implanting or deploying the device  10  so that the vascular defect  160  is substantially filled volumetrically by a combination of device and blood contained therein. The device  10  may be configured to be sufficiently conformal to adapt to irregular shaped vascular defects  160  so that at least about 75%, in some cases about 80%, of the vascular defect volume is occluded by a combination of device  10  and blood contained therein. 
     In particular, for some treatment embodiments, it may be desirable to choose a device  10  that is properly oversized in a transverse dimension so as to achieve a desired conformance, radial force and fit after deployment of the device  10 .  FIGS. 20-22  illustrate a schematic representation of how a device  10  may be chosen for a proper fit after deployment that is initially oversized in a transverse dimension by at least about 10% of the largest transverse dimension of the vascular defect  160  and sometimes up to about 100% of the largest transverse dimension. For some embodiments, the device  10  may be oversized a small amount (e.g. less than about 1.5 mm) in relation to measured dimensions for the width, height or neck diameter of the vascular defect  160 . 
     In  FIG. 20 , a vascular defect  160  in the form of a cerebral aneurysm is shown with horizontal arrows  180  and vertical arrows  182  indicating the approximate largest interior dimensions of the defect  160 . Arrow  180  extending horizontally indicates the largest transverse dimension of the defect  160 . In  FIG. 21 , a dashed outline  184  of a device for treatment of the vascular defect  10  is shown superimposed over the vascular defect  160  of  FIG. 20  illustrating how a device  10  that has been chosen to be approximately 20% oversized in a transverse dimension would look in its unconstrained, relaxed state.  FIG. 22  illustrates how the device  10  which is indicated by the dashed line  184  of  FIG. 21  might conform to the interior surface of the vascular defect  160  after deployment whereby the nominal transverse dimension of the device  10  in a relaxed unconstrained state has now been slightly constrained by the inward radial force  185  exerted by the vascular defect  160  on the device  10 . In response, as the filaments  14  of the device  10  and thus the permeable shell  40  made therefrom have a constant length, the device  10  has assumed a slightly elongated shape in the axial or longitudinal axis of the device  10  so as to elongate and better fill the interior volume of the defect  160  as indicated by the downward arrow  186  in  FIG. 22 . 
     Once a properly sized device  10  has been selected, the delivery and deployment process may then proceed. It should also be noted also that the properties of the device embodiments  10  and delivery system embodiments  112  discussed herein generally allow for retraction of a device  10  after initial deployment into a defect  160 , but before detachment of the device  10 . Therefore, it may also be possible and desirable to withdraw or retrieve an initially deployed device  10  after the fit within the defect  160  has been evaluated in favor of a differently sized device  10 . An example of a terminal aneurysm  160  is shown in  FIG. 23  in section. The tip  151  of a catheter, such as a microcatheter  61  may be advanced into or adjacent the vascular site or defect  160  (e.g. aneurysm) as shown in  FIG. 24 . For some embodiments, an embolic coil or other vaso-occlusive device or material  176  (as shown for example in  FIG. 19 ) may optionally be placed within the aneurysm  160  to provide a framework for receiving the device  10 . In addition, a stent  173  may be placed within a parent vessel  174  of some aneurysms substantially crossing the aneurysm neck prior to or during delivery of devices for treatment of a patient&#39;s vasculature discussed herein (also as shown for example in  FIG. 19 ). An example of a suitable microcatheter  61  having an inner lumen diameter of about 0.020 inches to about 0.022 inches is the Rapid Transit® manufactured by Cordis Corporation. Examples of some suitable microcatheters  61  may include microcatheters having an inner lumen diameter of about 0.026 inch to about 0.028 inch, such as the Rebar® by Ev3 Company, the Renegade Hi-Flow® by Boston Scientific Corporation, and the Mass Transit® by Cordis Corporation. Suitable microcatheters having an inner lumen diameter of about 0.031 inch to about 0.033 inch may include the Marksmen® by Chestnut Medical Technologies, Inc. and the Vasco 28® by Balt Extrusion. A suitable microcatheter  61  having an inner lumen diameter of about 0.039 inch to about 0.041 inch includes the Vasco 35 by Balt Extrusion. These microcatheters  61  are listed as exemplary embodiments only, other suitable microcatheters may also be used with any of the embodiments discussed herein. 
     Detachment of the device  10  from the delivery apparatus  110  may be controlled by a control switch  188  disposed at a proximal end of the delivery system  112 , which may also be coupled to an energy source  142 , which severs the tether  72  that secures the proximal hub  68  of the device  10  to the delivery apparatus  110 . While disposed within the microcatheter  61  or other suitable delivery system  112 , as shown in  FIG. 11 , the filaments  14  of the permeable shell  40  may take on an elongated, non-everted configuration substantially parallel to each other and a longitudinal axis of the catheter  61 . Once the device  10  is pushed out of the distal port of the microcatheter  61 , or the radial constraint is otherwise removed, the distal ends  62  of the filaments  14  may then axially contract towards each other so as to assume the globular everted configuration within the vascular defect  160  as shown in  FIG. 25 . 
     The device  10  may be inserted through the microcatheter  61  such that the catheter lumen  120  restrains radial expansion of the device  10  during delivery. Once the distal tip or deployment port of the delivery system  112  is positioned in a desirable location adjacent or within a vascular defect  160 , the device  10  may be deployed out the distal end of the catheter  61  thus allowing the device to begin to radially expand as shown in  FIG. 25 . As the device  10  emerges from the distal end of the delivery system  112 , the device  10  expands to an expanded state within the vascular defect  160 , but may be at least partially constrained by an interior surface of the vascular defect  160 . 
     Upon full deployment, radial expansion of the device  10  may serve to secure the device  10  within the vascular defect  160  and also deploy the permeable shell  40  across at least a portion of an opening  190  (e.g. aneurysm neck) so as to at least partially isolate the vascular defect  160  from flow, pressure or both of the patient&#39;s vasculature adjacent the vascular defect  160  as shown in  FIG. 26 . The conformability of the device  10 , particularly in the neck region  190  may provide for improved sealing. For some embodiments, once deployed, the permeable shell  40  may substantially slow flow of fluids and impede flow into the vascular site and thus reduce pressure within the vascular defect  160 . For some embodiments, the device  10  may be implanted substantially within the vascular defect  160 , however, in some embodiments, a portion of the device  10  may extend into the defect opening or neck  190  or into branch vessels. 
     One exemplary case study that has been conducted includes a procedure performed on a female canine where an aneurysm was surgically created in the subject canine. The target aneurysm prior to treatment had a maximum transverse dimension of about 8 mm, a length of about 10 mm and a neck measurement of about 5.6 mm. The device  10  deployed included a permeable shell  40  formed of 144 resilient filaments having a transverse diameter of about 0.0015 inches braided into a globular structure having a transverse dimension of about 10 mm and a longitudinal length of about 7 mm in a relaxed expanded state. The maximum size 100 of the pores  64  of the expanded deployed permeable shell  40  was about 0.013 inches. The device was delivered to the target aneurysm using a 5 Fr. Guider Softip XF guide catheter made by Boston Scientific. The maximum size 100 of the pores  64  of the portion of the expanded deployed permeable shell  40  that spanned the neck of the aneurysm again was about 0.013 inches. Five minutes after detachment from the delivery system, the device  10  had produced acute occlusion of the aneurysm. 
     Another exemplary case study conducted involved treatment of a surgically created aneurysm in a New Zealand White Rabbit. The target aneurysm prior to treatment had a maximum transverse dimension of about 3.6 mm, length of about 5.8 mm and a neck measurement of about 3.4 mm. The device  10  deployed included a permeable shell formed of 144 resilient filaments having a transverse diameter of about 0.001 inches braided into a globular structure having a transverse dimension of about 4 mm and a length of about 5 mm in a relaxed expanded state. The pore size 100 of the portion of the braided mesh of the expanded deployed permeable shell  40  that was configured to span the neck of the vascular defect was about 0.005 inches. The device was delivered to the surgically created aneurysm with a 5 Fr. Envoy STR guide catheter manufactured by Cordis Neurovascular. A Renegade Hi-Flo microcatheter manufactured by Boston Scientific having an inner lumen diameter of about 0.027 inches was then inserted through the guide catheter and served as a conduit for delivery of the device  10  secured to a distal end of a delivery apparatus. Once the device  10  was deployed within the vascular defect  160 , the vascular defect  160  achieved at least partial occlusion at 5 minutes from implantation. However, due to the sensitivity of the subject animal to angiographic injection and measurement, no further data was taken during the procedure. Complete occlusion was observed for the device when examined at 3 weeks from the procedure. 
     For some embodiments, as discussed above, the device  10  may be manipulated by the user to position the device  10  within the vascular site or defect  160  during or after deployment but prior to detachment. For some embodiments, the device  10  may be rotated in order to achieve a desired position of the device  10  and, more specifically, a desired position of the permeable shell  40 , prior to or during deployment of the device  10 . For some embodiments, the device  10  may be rotated about a longitudinal axis of the delivery system  112  with or without the transmission or manifestation of torque being exhibited along a middle portion of a delivery catheter being used for the delivery. It may be desirable in some circumstances to determine whether acute occlusion of the vascular defect  160  has occurred prior to detachment of the device  10  from the delivery apparatus  110  of the delivery system  112 . These delivery and deployment methods may be used for deployment within berry aneurysms, terminal aneurysms, or any other suitable vascular defect embodiments  160 . Some method embodiments include deploying the device  10  at a confluence of three vessels of the patient&#39;s vasculature that form a bifurcation such that the permeable shell  40  of the device  10  substantially covers the neck of a terminal aneurysm. Once the physician is satisfied with the deployment, size and position of the device  10 , the device  10  may then be detached by actuation of the control switch  188  by the methods described above and shown in  FIG. 26 . Thereafter, the device  10  is in an implanted state within the vascular defect  160  to effect treatment thereof. 
       FIG. 27  illustrates another configuration of a deployed and implanted device in a patient&#39;s vascular defect  160 . While the implantation configuration shown in  FIG. 26  indicates a configuration whereby the longitudinal axis  46  of the device  10  is substantially aligned with a longitudinal axis of the defect  160 , other suitable and clinically effective implantation embodiments may be used. For example,  FIG. 27  shows an implantation embodiment whereby the longitudinal axis  46  of the implanted device  10  is canted at an angle of about 10 degrees to about 90 degrees relative to a longitudinal axis of the target vascular defect  160 . Such an alternative implantation configuration may also be useful in achieving a desired clinical outcome with acute occlusion of the vascular defect  160  in some cases and restoration of normal blood flow adjacent the treated vascular defect.  FIG. 28  illustrates a device  10  implanted in an irregularly shaped vascular defect  160 . The aneurysm  160  shown has at least two distinct lobes  192  extending from the main aneurysm cavity. The two lobes  192  shown are unfilled by the deployed vascular device  10 , yet the lobes  192  are still isolated from the parent vessel of the patient&#39;s body due to the occlusion of the aneurysm neck portion  190 . 
     Markers, such as radiopaque markers, on the device  10  or delivery system  112  may be used in conjunction with external imaging equipment (e.g., x-ray) to facilitate positioning of the device or delivery system during deployment. Once the device is properly positioned, the device  10  may be detached by the user. For some embodiments, the detachment of the device  10  from the delivery apparatus  110  of the delivery system  112  may be affected by the delivery of energy (e.g. heat, radiofrequency, ultrasound, vibrational, or laser) to a junction or release mechanism between the device  10  and the delivery apparatus  110 . Once the device  10  has been detached, the delivery system  112  may be withdrawn from the patient&#39;s vasculature or patient&#39;s body  158 . For some embodiments, a stent  173  may be place within the parent vessel substantially crossing the aneurysm neck  190  after delivery of the device  10  as shown in  FIG. 19  for illustration. 
     For some embodiments, a biologically active agent or a passive therapeutic agent may be released from a responsive material component of the device  10 . The agent release may be affected by one or more of the body&#39;s environmental parameters or energy may be delivered (from an internal or external source) to the device  10 . Hemostasis may occur within the vascular defect  160  as a result of the isolation of the vascular defect  160 , ultimately leading to clotting and substantial occlusion of the vascular defect  160  by a combination of thrombotic material and the device  10 . For some embodiments, thrombosis within the vascular defect  160  may be facilitated by agents released from the device  10  and/or drugs or other therapeutic agents delivered to the patient. 
     For some embodiments, once the device  10  has been deployed, the attachment of platelets to the permeable shell  40  may be inhibited and the formation of clot within an interior space of the vascular defect  160 , device, or both promoted or otherwise facilitated with a suitable choice of thrombogenic coatings, anti-thrombogenic coatings or any other suitable coatings (not shown) which may be disposed on any portion of the device  10  for some embodiments, including an outer surface of the filaments  14  or the hubs  66  and  68 . Such a coating or coatings may be applied to any suitable portion of the permeable shell  40 . Energy forms may also be applied through the delivery apparatus  110  and/or a separate catheter to facilitate fixation and/or healing of the device  10  adjacent the vascular defect  160  for some embodiments. One or more embolic devices or embolic material  176  may also optionally be delivered into the vascular defect  160  adjacent permeable shell portion that spans the neck or opening  190  of the vascular defect  160  after the device  10  has been deployed. For some embodiments, a stent or stent-like support device  173  may be implanted or deployed in a parent vessel adjacent the defect  160  such that it spans across the vascular defect  160  prior to or after deployment of the vascular defect treatment device  10 . 
     In any of the above embodiments, the device  10  may have sufficient radial compliance so as to be readily retrievable or retractable into a typical microcatheter  61 . The proximal portion of the device  10 , or the device as a whole for some embodiments, may be engineered or modified by the use of reduced diameter filaments, tapered filaments, or filaments oriented for radial flexure so that the device  10  is retractable into a tube that has an internal diameter that is less than about 0.7 mm, using a retraction force less than about 2.7 Newtons (0.6 lbf) force. The force for retrieving the device  10  into a microcatheter  61  may be between about 0.8 Newtons (0.18 lbf) and about 2.25 Newtons (0.5 lbf). 
     Engagement of the permeable shell  40  with tissue of an inner surface of a vascular defect  160 , when in an expanded relaxed state, may be achieved by the exertion of an outward radial force against tissue of the inside surface of the cavity of the patient&#39;s vascular defect  160  as shown in  FIG. 29 . A similar outward radial force may also be applied by a proximal end portion and permeable shell  40  of the device  10  so as to engage the permeable shell  40  with an inside surface or adjacent tissue of the vascular defect  160 . Such forces may be exerted in some embodiments wherein the nominal outer transverse dimension or diameter of the permeable shell  40  in the relaxed unconstrained state is larger than the nominal inner transverse dimension of the vascular defect  160  within which the device  10  is being deployed, i.e., oversizing as discussed above. The elastic resiliency of the permeable shell  40  and filaments  14  thereof may be achieved by an appropriate selection of materials, such as superelastic alloys, including nickel titanium alloys, or any other suitable material for some embodiments. The conformability of a proximal portion of the permeable shell  40  of the device  10  may be such that it will readily ovalize to adapt to the shape and size of an aneurysm neck  190 , as shown in  FIGS. 20-22 , thus providing a good seal and barrier to flow around the device. Thus, the device  10  may achieve a good seal, substantially preventing flow around the device without the need for fixation members that protrude into the parent vessel. 
     Some implanted device embodiments  10  have the ends of the filaments  14  of the permeable shell  40  disposed even with or just within a plane formed by the apices of the filaments disposed adjacent to the ends. Some embodiments of the device  10  may also include a sealing member disposed within or about a perimeter zone  198  or other suitable portion of the permeable shell  40  and be configured to facilitate the disruption of flow, a fibrotic tissue response, or physically form a seal between the permeable shell  40  and a surface of the patient&#39;s vasculature. The sealing member may comprise coatings, fibers or surface treatments as described herein. The sealing member may be in a part or all of an area of the periphery of the device adjacent where the device contacts the wall of the aneurysm near the aneurysm neck (sealing zone  198 ) as shown in  FIGS. 29 and 30 . The zone may extend from about the apex of the outer proximal end radius  88  for a distance up to about 20% of the height of the expanded device  10 . The sealing zone  198  may include between about 5% and 30% of the device  10  surface area. Since the flow of blood into an aneurysm  160  generally favors one side of the opening, the sealing member may be incorporated in or attached to the permeable shell  40  structure throughout the peripheral area (sealing zone  198 ) shown in  FIG. 30 . Some embodiments of the sealing member may include a swellable polymer. In some embodiments, the sealing member may include or bioactive material or agent such as a biologic material or biodegradable, bioresorbable or other bioactive polymer or copolymers thereof. 
     Any embodiment of devices for treatment of a patient&#39;s vasculature  10 , delivery system  112  for such devices  10  or both discussed herein may be adapted to deliver energy to the device for treatment of a patient&#39;s vasculature or to tissue surrounding the device  10  at the implant site for the purpose of facilitating fixation of a device  10 , healing of tissue adjacent the device or both. In some embodiments, energy may be delivered through a delivery system  112  to the device  10  for treatment of a patient&#39;s vasculature such that the device  10  is heated. In some embodiments, energy may be delivered via a separate elongate instrument (e.g. catheter, not shown) to the device  10  for treatment of a patient&#39;s vasculature and/or surrounding tissue at the site of the implant  154 . Examples of energy embodiments that may be delivered include but are not limited to light energy, thermal or vibration energy, electromagnetic energy, radio frequency energy and ultrasonic energy. For some embodiments, energy delivered to the device  10  may trigger the release of chemical or biologic agents to promote fixation of a device for treatment of a patient&#39;s vasculature  10  to a patient&#39;s tissue, healing of tissue disposed adjacent such a device  10  or both. 
     The permeable shell  40  of some device embodiments  10  may also be configured to react to the delivery of energy to effect a change in the mechanical or structural characteristics, deliver drugs or other bioactive agents or transfer heat to the surrounding tissue. For example, some device embodiments  10  may be made softer or more rigid from the use of materials that change properties when exposed to electromagnetic energy (e.g., heat, light, or radio frequency energy). In some cases, the permeable shell  40  may include a polymer that reacts in response to physiologic fluids by expanding. An exemplary material is described by Cox in U.S. Patent Application No. 2004/0186562, filed Jan. 22, 2004, titled “Aneurysm Treatment Device and Method of Use”, which is incorporated by reference herein in its entirety. 
     Device embodiments  10  and components thereof discussed herein may take on a large variety of configurations to achieve specific or generally desirable clinical results. In some device embodiments  10 , the start of the braided structure of the permeable shell  40  may be delayed from the proximal hub  68  so that the filaments  1  emanate from the proximal hub  68  in a spoke-like radial fashion as shown in the proximal end view of a device in  FIG. 31 . A flattened analog version of the braid pattern of  FIG. 31  is also shown in  FIG. 33 . This configuration may result in a smaller width gap between the filaments  14  at a given radial distance from the proximal hub  68  relative to a fully braided configuration, the flattened analog pattern of which is shown in  FIG. 34 . This may provide better flow disruption and promote hemostasis in the area of the device  10  that may be subjected to the highest flow rates.  FIG. 32  illustrates a flattened analog representation of a non-braided filament structure for reference. 
     The woven structure may include a portion where the weave or braid of the filaments  14  is interrupted as shown in a flat pattern analog pattern in  FIG. 35 . In the interrupted region, the filaments  14  may be substantially parallel to each other. The interrupted area may provide a region with different mechanical characteristics such as radial stiffness and/or compliance. Further, the interrupted region may allow for the addition of non-structural fibers or sealing members  200  as described herein or other elements to facilitate fixation, healing, fibrosis or thrombosis. The interrupted region may be within, part of or adjacent to the sealing member zone  198  as shown in  FIGS. 29 and 30 . The interrupted region may be less than about 50% of the surface area and may be between about 5% and 25% of the surface area. 
     In some embodiments, filamentary or fibrous members that are substantially non-structural may be attached or interwoven into the structural filaments of a portion of the permeable shell to increase a resistance to the flow of blood through the permeable shell structure  40 . In some embodiments, a plurality of fibers  200  may be attached on the inner surface of the permeable shell  40  near the proximal hub  68  as shown in  FIG. 36 . The fibrous members  200  may be the fibers that form the detachment system tether for some embodiments. In some embodiments, one or more fibers  200  may be interwoven into the permeable shell filaments  14  as shown in  FIG. 37 . The non-structural fibers  200 , which may be microfibers or any other suitable fibers, may be polymeric. The non-structural fibers  200  may include, but not limited to, any of the fibers or microfibers discussed or incorporated herein. 
     In some cases, device embodiments for treatment of a patient&#39;s vasculature  10  may generally be fabricated by braiding a substantially tubular braided structure with filamentary elements  14 , forming the braided tubular structure into a desired shape, and heat setting the braided formed filaments into the desired shape. Once so formed, the ends of the elongate resilient filaments  14  may then be secured together relative to each other by any of the methods discussed above and proximal and distal hubs  66  and  68  added. 
     Such a braiding process may be carried out by automated machine fabrication or may also be performed by hand. An embodiment of a process for braiding a tubular braided structure by a manual process is shown in  FIG. 38 . A plurality of elongate resilient filaments  14  are secured at one end of an elongate cylindrical braiding mandrel  202  by a constraining band  204 . The band  204  may include any suitable structure that secured the ends of the filaments  14  relative to the mandrel  202  such as a band of adhesive tape, an elastic band, an annular clamp or the like. The loose ends of the filaments  14  opposite the secured ends are being manipulated in a braided or woven pattern as indicated by the arrows  206  to achieve a one over-one under braid pattern for generation of a braided tubular member  208 . As discussed above, although a one over-one under simple braid pattern is shown and discussed, other braid or weave patterns may also be used. One such example of another braid configuration may include a two over-one under pattern.  FIG. 39  illustrates the braided tubular member  208  taking shape and lengthening as the braiding process continues as indicated by the arrows  206  in  FIG. 39 . Once the braided tubular member  208  achieves sufficient length, it may be removed from the braiding mandrel  202  and positioned within a shaping fixture such as the shaping fixture embodiments shown in  FIGS. 40 and 41 . 
       FIG. 40  shows the tubular braided member  208  disposed over an internal rod mandrel  210  that extends through central lumens of an internal ball mandrel  212  and a pair of opposed recessed end forming mandrels  214 . The tubular braided member  208  is also disposed over an outer surface of the internal ball mandrel  212  and within an inner lumen of each of the end forming mandrels  214 . In order to hold the braided tubular member  208  onto an outer surface contour of the internal ball mandrel  212 , including the recessed ends  216  thereof, the end forming mandrels  214  are configured to be pushed against and into the recessed ends  216  of the internal ball mandrel  212  such that the inside surface of the braided tubular member  208  is held against the outer contour of the internal ball mandrel  212  and fixed in place. This entire fixture  220  with the inside surface of the braided tubular structure  208  held against the outside surface of the internal ball mandrel  212  may then be subjected to an appropriate heat treatment such that the resilient filaments  14  of the braided tubular member  208  assume or are otherwise shape-set to the outer contour of the central ball mandrel  212 . In some embodiments, the filamentary elements  14  of the permeable shell  40  may be held by a fixture configured to hold the permeable shell  40  in a desired shape and heated to about 475-525 degrees C. for about 5-10 minutes to shape-set the structure. 
     The central ball mandrel  212  may be configured to have any desired shape so as to produce a shape set tubular braided member  208  that forms a permeable shell  40  having a desired shape and size such as the globular configuration of the device  10  of  FIGS. 3-6  above, or any other suitable configuration. As such, the central ball mandrel  212  may also be a globular-shaped ball with recesses in opposing sides for the hubs  66  and  68  that is placed inside the tubular braid  208 . A mold or molds that have one or more pieces that are assembled to form a cavity with the desired device shape may also be used in conjunction with or in place of the end forming mandrels  214 . Once the heat set process is complete, fibers, coatings, surface treatments may be added to certain filaments, portions of filaments, or all of the permeable shell  40  structures that results. Further, for some embodiments of device processing, the permeable shell  40  may be formed as discussed above by securing proximal ends  60  and distal ends  62  of elongate filamentary elements  14 , or to respective proximal and distal hubs  66  and  68 . 
       FIG. 41  shows another embodiment of a fixture for shape setting the permeable shell  40  of a device for treatment of a patient&#39;s vasculature. The fixture embodiment  230  of  FIG. 41  may be used in essentially the same manner as the fixture embodiment  220  of  FIG. 40 , except that instead of a central ball mandrel  212 , an internal tube mandrel  232  is used in conjunction with an external tube restraint  234  in order to hold the shape of the braided tubular member  208  during the heat setting process. More specifically, the tubular braided member  208  is disposed over an internal rod mandrel  210  that extends through central lumens of the internal tube mandrel  232  and a pair of opposed recessed end forming mandrels  214 . The tubular braided member  208  is also disposed over an outer surface of the internal tube mandrel  232  and within an inner lumen of each of the end forming mandrels  214 . 
     In order to hold the braided tubular member  208  into a desired shape, including the recessed ends thereof, the end forming mandrels  214  are configured to be pushed against and into recessed ends  238  of the internal tube mandrel  232  such that the inside surface of the braided tubular member  208  is held against the outer contour of the internal tube mandrel  232  and fixed in place at the ends of the tube mandrel  232 . Between the ends of the tube mandrel  232 , the braided tubular member  208  radially expands outwardly until it touches and is radially constrained by an inside surface of an external tube mandrel  234 . The combination of axial restraint and securement of the braided tubular member  208  at the ends of the internal tube mandrel  232  in conjunction with the inward radial restraint on an outside surface of the braided tubular member  208  disposed between the proximal and distal ends thereof, may be configured to produce a desired globular configuration suitable for the permeable shell  40  of the device  10 . 
     Once again, this entire fixture  230  with the inside surface of the ends of the braided tubular structure  208  held against the outside surface of the ends of the internal tube mandrel  232  and an outside surface of the braided tubular member  208  radially constrained by an inside surface  233  of the external tube member  234 , may then be subjected to an appropriate heat treatment. The heat treatment may be configured such that the resilient filaments  14  of the braided tubular member  208  assume or are otherwise shape-set to the globular contour of the filaments  14  generated by the fixture  230 . In some embodiments, the filamentary elements  14  of the permeable shell  40  may be held by a fixture configured to hold the braided tubular member  208  in a desired shape and heated to about 475-525 degrees C. for about 5-10 minutes to shape-set the structure. The internal tube mandrel  232  and inside surface  233  of the external tube member  234  may be so configured to have any desired shape so as to produce a shape set tubular braided member  208  that forms a permeable shell  40  having a desired shape and size such as the globular configuration of the device of  FIGS. 3-6  above, or any other suitable configuration. 
     As shown, the arced portion of the filaments  1110  may have a sinusoidal-like shape with a first or outer radius  1126  and a second or inner radius  1128  near a first end of the permeable shell as shown in  FIG. 42 . This sinusoid-like shape may provide a concavity in the proximal end that may reduce the obstruction of flow in the parent vessel. For some embodiments, the first radius and second radius of the permeable shell may be between about 0.12 mm to about 3 mm. For some embodiments, the distance between the first end and second end may be less than about 60% of the overall length of the permeable shell  1106  for some embodiments. Such a configuration may allow for the second end to flex downward toward the first end when the device meets resistance at the distal end and thus may provide longitudinal conformance. The filaments  1110  may be shaped in some embodiments such that there are no portions that are without curvature over a distance of more than about 2 millimeters. Thus, for some embodiments, each filament  1110  may have a substantially continuous curvature. This substantially continuous curvature may provide smooth deployment and may reduce the risk of vessel perforation. For some embodiments, one of the ends may be retracted or everted to a greater extent than the other so as to be more longitudinally or axially conformal than the other end. 
     The first radius  1126  and second radius  1128  of the permeable shell  1106  may be between about 0.12 mm to about 3 mm for some embodiments. For some embodiments, the distance between the first end  1112  and second end  1114  may be less than about 60% of the overall length of the support structure. A gap between the hubs at the first end and second end may allow for the distal or second end hub to flex downward toward the proximal or first end hub  1112  when the device meets resistance at the distal end and thus provides longitudinal conformance. The filaments  1110  may be shaped such that there are no portions that are without curvature over a distance of more than about 2 millimeters. Thus, for some embodiments, each filament  1110  may have a substantially continuous curvature. This substantially continuous curvature may provide smooth deployment and may reduce the risk of vessel perforation. The distal or second end  1104  may be retracted or everted to a greater extent than the proximal end such that the distal end portion of the permeable shell may be more radially conformal than the proximal end portion. Conformability of a distal end portion may provide better device conformance to irregular shaped aneurysms or other vascular defects. A convex surface of the device may flex inward forming a concave surface to conform to curvature of a vascular site. 
       FIG. 43  shows an enlarged view of the filaments  1110  disposed within a first hub  1112  or end portion of the device  100  with the filaments  1110  constrained and tightly packed by an outer ring  1132  of the first hub. A tether member  134  may be disposed within a middle portion of the filaments  1110 . Such a tether  1134  may be a dissolvable, severable or releasable tether that may be part of a release mechanism  1124  used to deploy the device  1100 .  FIGS. 43A-E  illustrate various embodiments of first ends or hubs  112  showing the configuration of filaments  1110 , mandrels  1136 , tethers and the like which may be tightly packed and radially constrained by respective outer ring members  1132 . In some embodiments, the braided or woven structure may be constructed using a large number of small filaments. The number of filaments may be greater than 1125 and may be between 80 and 180. In some embodiments, the braided structure of the permeable shell may be constructed with two or more sizes of filaments. For example, the structure may have several larger filaments  1138  that provide structural support and several smaller filaments  1110  that provide the desired pore size and density and thus flow resistance. For some embodiments, smaller filaments  1110  may have a transverse dimension or diameter of about 0.015 mm to about 0.05 mm and larger filaments  1138  may have a transverse dimension or diameter of about 0.04 mm to about 0.1 mm. The filaments may be braided in a plain weave that is one under, one over structure or a supplementary weave; more than one warp interlace with one or more than one weft. The pick count may be varied between about 25 and 200 picks per inch (PPI). 
       FIG. 43A  illustrates a transverse section of a first hub portion having a center mandrel  1136  disposed within 8 larger filaments  1138  which are disposed within and in contact with a plurality of small filaments  1110 . There are substantially three circumferential rings of small filaments disposed between the larger filaments and the inner surface of the outer ring. The small filaments  1110  are disposed within and  30  radially constrained by the outer ring  132 . Once the first hub is formed, the central mandrel  1136  may be removed with a releasable tether disposed in its place. The embodiment of  FIG. 43B  has a configuration similar to that of the embodiment of  FIG. 43A  but with substantially 4 circumferential rings of smaller filaments  1110  disposed between the larger filaments  1138  and the inner surface of the outer ring. The embodiment of  FIG. 43C  includes a configuration similar to that of  FIG. 43A  but with larger filaments  1138  disposed between a single inner circumferential ring of smaller filaments  1110  which are disposed between a mandrel and the larger filaments  1138 . A single circumferential ring of smaller filaments is disposed between the larger 5 filaments and the inner surface of the outer ring.  FIG. 43D  shows an embodiment of a first hub having a configuration similar to that of the embodiment of  FIG. 43C  but with two circumferential rings of smaller filaments  1110  disposed between the larger filaments and an inner surface of an outer ring.  FIG. 43E  illustrates another embodiment which includes small filaments  1110  disposed radially within a plurality of 10 larger filaments  1140  with yet another ring of smaller filaments disposed radially outside the larger filaments. All filaments of the embodiment of  FIG. 43E  are disposed within and constrained by an outer ring  1132  which may be configured to secure the large and small filaments in place relative to each other within the outer ring. 
     For some embodiments, material may be attached to filaments  14  of the permeable shell  40  of a device  10  such that it substantially reduces the size of the fenestrations, cells or pores  64  between filaments  14  and thus reduces the porosity in that area. For example, coating embodiments may be disposed on portions of the filaments  14  to create small fenestrations or cells and thus higher density of the permeable shell  40 . Active materials such as a responsive hydrogel may be attached or otherwise incorporated into permeable shell  40  of some embodiments such that it swells upon contact with liquids over time to reduce the porosity of the permeable shell  40 . 
     Device embodiments  10  discussed herein may be coated with various polymers to enhance it performance, fixation and/or biocompatibility. In addition, device embodiments  10  may be made of various biomaterials known in the art of implant devices including but not limited to polymers, metals, biological materials and composites thereof. Device embodiments discussed herein may include cells and/or other biologic material to promote healing. Device embodiments discussed herein may also be constructed to provide the elution or delivery of one or more beneficial drugs, other bioactive substances or both into the blood or the surrounding tissue. 
     Permeable shell embodiments  40  of devices for treatment of a patient&#39;s vasculature  10  may include multiple layers. A first or outer layer may be constructed from a material with low bioactivity and hemocompatibility so as to minimize platelet aggregation or attachment and thus the propensity to form clot and thrombus. Optionally, an outer layer may be coated or incorporate an antithrombogenic agent such as heparin or other antithrombogenic agents described herein or known in the art. One or more inner layers disposed towards the vascular defect in a deployed state relative to the first layer may be constructed of materials that have greater bioactivity and/or promote clotting and thus enhance the formation of an occlusive mass of clot and device within the vascular defect. Some materials that have been shown to have bioactivity and/or promote clotting include silk, polylactic acid (PLA), polyglycolic acid (PGA), collagen, alginate, fibrin, fibrinogen, fibronectin, Methylcellulose, gelatin, Small Intestinal Submucosa (SIS), poly-N-acetylglucosamine and copolymers or composites thereof. 
     Bioactive agents suitable for use in the embodiments discussed herein may include those having a specific action within the body as well as those having nonspecific actions. Specific action agents are typically proteinaceous, including thrombogenic types and/or forms of collagen, thrombin and fibrogen (each of which may provide an optimal combination of activity and cost), as well as elastin and von Willebrand factor (which may tend to be less active and/or expensive agents), and active portions and domains of each of these agents. Thrombogenic proteins typically act by means of a specific interaction with either platelets or enzymes that participate in a cascade of events leading eventually to clot formation. Agents having nonspecific thrombogenic action are generally positively charged molecules, e.g., polymeric molecules such as chitosan, polylysine, poly(ethylenimine) or acrylics polymerized from acrylimide or methacrylamide which incorporate positively-charged groups in the form of primary, secondary, or tertiary amines or quarternary salts, or non-polymeric agents such as (tridodecylmethylammonium chloride). Positively charged hemostatic agents promote clot formation by a non-specific mechanism, which includes the physical adsorption of platelets via ionic interactions between the negative charges on the surfaces of the platelets and the positive charges of the agents themselves. 
     Device embodiments  10  herein may include a surface treatment or coating on a portion, side or all surfaces that promotes or inhibits thrombosis, clotting, healing or other embolization performance measure. The surface treatment or coating may be a synthetic, biologic or combination thereof. For some embodiments, at least a portion of an inner surface of the permeable shell  40  may have a surface treatment or coating made of a biodegradable or bioresorbable material such as a polylactide, polyglycolide or a copolymer thereof. Another surface treatment or coating material which may enhance the embolization performance of a device includes a polysachharide such as an alginate based material. Some coating embodiments may include extracellular matrix proteins such as ECM proteins. One example of such a coating may be Finale Prohealing coating which is commercially available from Surmodics Inc., Eden Prairie, Minn. Another exemplary coating may be Polyzene-F which is commercially available from CeloNovo BioSciences, Inc., Newnan, Ga. In some embodiments, the coatings may be applied with a thickness that is less than about 25% of a transverse dimension of the filaments  14 . 
     Antiplatelet agents may include aspirin, glycoprotein IIb/IIIa receptor inhibitors (including, abciximab, eptifibatide, tirofiban, lamifiban, fradafiban, cromafiban, toxifiban, XV454, lefradafiban, klerval, lotrafiban, orbofiban, and xemilofiban), dipyridamole, apo-dipyridamole, persantine, prostacyclin, ticlopidine, clopidogrel, cromafiban, cilostazol, and nitric oxide. To deliver nitric oxide, device embodiments may include a polymer that releases nitric oxide. Device embodiments  10  may also deliver or include an anticoagulant such as heparin, low molecular weight heparin, hirudin, warfarin, bivalirudin, hirudin, argatroban, forskolin, ximelagatran, vapiprost, prostacyclin and prostacyclin analogues, dextran, synthetic antithrombin, Vasoflux, argatroban, efegatran, tick anticoagulant peptide, Ppack, HMG-CoA reductase inhibitors, and thromboxane A2 receptor inhibitors. 
     In some embodiments, the permeable shell  40  of a device  10  may be coated with a composition that may include nanoscale structured materials or precursors thereof (e.g., self-assembling peptides). The peptides may have with alternating hydrophilic and hydrophobic monomers that allow them to self-assemble under physiological conditions. The composition may comprise a sequence of amino acid residues. In some embodiments, the permeable shell may include a thin metallic film material. The thin film metal may be fabricated by sputter deposition and may be formed in multiple layers. The thin film may be a nickel-titanium alloy also known as nitinol. 
     With regard to the above detailed description, like reference numerals used therein refer to like elements that may have the same or similar dimensions, materials and configurations. While particular forms of embodiments have been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the embodiments of the invention. Accordingly, it is not intended that the invention be limited by the forgoing detailed description.