Vascular occlusion device and methods of making and using same

Abstract

To prevent herniation of a device during deployment and retention within an anatomical cavity.SOLUTION: A vaso-occlusive coil is formed of a wire having a primary configuration in a constrained condition. The coil assumes a secondary configuration in a relaxed, unconstrained condition. The secondary configuration comprises a primary portion comprising a plurality of primary loops, including a distal-most primary loop. A distal anchoring loop is connected to the distal end of the distal-most primary loop. The distal anchoring loop has a substantially triangular shape and is much smaller than the distal-most primary loop.SELECTED DRAWING: Figure 14

Description

[Technical field]

[0001] The present disclosure relates generally to medical devices and intravascular medical procedures, and more particularly to devices for occluding vascular defects, such as aneurysms, or other anatomical cavities, and methods for making and using such devices. [Background technology]

[0002] Vascular occlusion devices or implants are used for a variety of reasons, including the treatment of intravascular aneurysms. Aneurysms are dilations of vasculature, such as blood vessels, that can rupture, clot, or dissociate, posing a risk to a patient's health. For example, an aneurysm in a patient's brain may rupture, causing a stroke, leading to brain damage and death. Cerebral aneurysms may be detected in a patient, for example, after a stroke or hemorrhage, and treated by application of a vascular occlusion device.

[0003] A commonly used vaso-occlusive device comprises a soft, helically wound coil formed by winding a platinum (or platinum alloy) wire strand around a "primary" mandrel. This coil is then wound around a larger "secondary" mandrel and heat treated to impart a secondary shape. For example, U.S. Pat. No. 4,994,069 issued to Ritchart et al. (which is incorporated herein in its entirety by reference as if set forth in its entirety) describes a vaso-occlusive device that assumes a straight, helical primary shape when stretched for placement through the lumen of a delivery catheter, and a folded, complex secondary shape when released from the delivery catheter and placed in the vasculature. Complex three-dimensional secondary shapes can be imparted to the vaso-occlusive device to better frame and fill the aneurysm, and the stiffness / flexibility of the vaso-occlusive device can be altered.

[0004] To deliver a vaso-occlusive device to a desired site within the vasculature, e.g., into an aneurysmal sac, it is known to first position a small profile delivery catheter or "microcatheter" at the site using a guidewire. Typically, the distal end of the microcatheter is provided with a selected preformed bend, e.g., 45°, 26°, "J" shaped, "S" shaped or other bend shape, by the attending physician or manufacturer depending on the patient's particular anatomy, so that when the guidewire is withdrawn, it will remain in a desired position to release one or more vaso-occlusive devices into the aneurysmal sac. A delivery or "pusher" assembly or "wire" is then threaded through the microcatheter until the vaso-occlusive device coupled to the distal end of the delivery assembly extends from the distal end opening of the microcatheter into the aneurysmal sac. Once inside the aneurysmal sac, a portion of the vaso-occlusive device can be deformed or bent to allow for more efficient and complete filling. The vaso-occlusive device is then released or "detached" from the distal end of the delivery assembly, and the delivery assembly is pulled back through the microcatheter. Depending on the particular needs of the patient, one or more additional vaso-occlusive devices can be pushed through the microcatheter and released into the same aneurysm sac.

[0005] Fluoroscopy is typically used to visualize the vaso-occlusion device during delivery into the aneurysm, while magnetic resonance imaging (MRI) is typically used to visualize the treatment site post-procedure (e.g., several weeks after initial treatment of the aneurysm) to ensure that the aneurysm sac has been adequately occluded. For this reason, it is important that the vaso-occlusion device be constructed to allow for its radiopacity during treatment of the aneurysm while minimizing visualization-impeding artifacts that arise during post-procedure MRI (i.e., MRI-compatible). It is also preferable that such vaso-occlusion devices be "soft" (i.e., laterally flexible or malleable) and thereby atraumatic, to prevent rupture of the delicate tissue of the aneurysm.

[0006] It is also important that such vaso-occlusive devices are retained within the aneurysm for an extended period of time. However, aneurysms with large mouths, commonly known as "wide-necked aneurysms," are difficult to place and retain within the aneurysm sac, and in particular small, relatively thin vaso-occlusive coils lack sufficient mechanical strength to maintain their position within such aneurysm sacs, no matter how skillfully they are placed. For example, small aneurysms (e.g., aneurysms having a diameter of less than about 7 mm, or even smaller, less than about 5 mm) are often characterized by a wide neck and a short dome. More specifically, small aneurysms often have a relatively wide neck compared to the size of the aneurysm (i.e., the ratio of the neck width to the aneurysm diameter is often greater for small aneurysms compared to such ratio for larger aneurysms). Due to the relatively wide neck, small aneurysms (generally wide-necked aneurysms) are at high risk of coil dislodging within the parent vessel both during placement and retention. Figure 1 shows a portion of a vaso-occlusive coil dislodging out of the aneurysm after introduction into the aneurysm.

[0007] Variations in the stiffness of the wires from which current vaso-occlusive devices are made, as well as variations in the stiffness of the stretch-resistant sutures often used in current coil designs, also lead to oversizing of the leading (or distal) loop. The distal loop is the first loop of the vaso-occlusive device that is deployed within the aneurysm. If the distal loop is oversized, there is a tendency for the distal tip (i.e., the tip of the distal loop) to detach out of the aneurysm during deployment. Figure 1 shows an example of detachment during initial deployment of a vaso-occlusive coil. As the vaso-occlusive coil is advanced out of the delivery catheter, the distal loop of the coil becomes unconstrained, and as the distal loop assumes an unconstrained configuration, the distal loop may bend within the aneurysm and the distal tip may detach from the aneurysm into the parent vessel. Figure 2 shows another example, where deployment of subsequent coils into the aneurysm may cause the distal loop to be displaced so much that it rotates and moves around, and this unpredictable movement may also cause detachment. To compensate for these conditions, clinicians are forced to constantly manipulate the vaso-occlusion coil and / or delivery catheter, such as advancing, retracting and / or rotating the coil and catheter while the coil is being deployed, to prevent dislodgement.

[0008] Several deployment techniques have also been developed to mitigate coil dislodgement during deployment. One such deployment technique, called the "remodeling or placement technique," utilizes a balloon or stent placed in the vessel adjacent to the neck region of the aneurysm to prevent the vaso-occlusive coil from exiting the aneurysm sac. Figure 3 illustrates the remodeling technique, which uses a balloon-actuated catheter. A balloon-actuated catheter is used to deploy a balloon adjacent to the neck region of the aneurysm. The balloon prevents the coil from dislodging from the aneurysm as it is deployed into the aneurysm. However, as shown in Figure 3, this technique carries the risk that the balloon may push the tip of the catheter into the dome of the aneurysm, causing the aneurysm to rupture. Figure 4 illustrates a placement technique using a stent. A stent is placed around the neck of the aneurysm and expanded to prevent the coil from exiting the aneurysm sac. Like balloon-actuated catheters, stents also carry the risk of pushing the tip of the catheter into the dome of the aneurysm, causing the aneurysm to rupture. Figure 5 illustrates another deployment technique for implanting a vaso-occlusive device, called a "recross." In this technique, a delivery catheter is extended through the opening of a stent. The stent technique can prevent the coils from jumping out of the aneurysm sac. However, because positioning the delivery catheter through the opening of a stent is inherently unpredictable, the maneuver of guiding and positioning the delivery catheter runs the risk of forcing the catheter tip into the dome, thereby rupturing the aneurysm.

[0009] To address these dislodgement and embedding issues, vaso-occlusion coils have been developed that provide higher neck coverage and shape stability to effectively “frame” the aneurysm. However, the three-dimensional shapes of current vaso-occlusion devices are either not suitable for framing the aneurysm or are prone to dislodgement during deployment within the aneurysm. Small aneurysms are best treated with as few coils as possible, and current vaso-occlusion devices are unable to balance shape stability and softness on their own. In fact, the shapes and configurations of current vaso-occlusion devices result in a directly proportional relationship between shape stability and softness. That is, the softer the device is (i.e., the less resistant it is to deformation due to external forces), the less stable the device is, and vice versa (i.e., the less soft the device is, the more stable the shape of the vaso-occlusion device is). Thus, although softer coils are less likely to rupture the aneurysm, they are unable to retain their shape, and therefore are more susceptible to dislodgement from the aneurysm during deployment and / or retention. Conversely, the stiffer the coil, the better it can hold its shape and frame the aneurysm, but the higher the stress it places on the aneurysm wall and the higher the risk of rupturing the aneurysm, especially small aneurysms that are at higher risk of rupture. Furthermore, especially with the outer complex shapes employed in current designs, the initial distal loops (e.g., the first and second loops) are more likely to detach from the aneurysm by being pushed out by subsequent loops during deployment.

[0010] Thus, there is a need for a vaso-occlusive device that can mitigate the problem of dislodgement during placement and retention, and provide effective framing of the aneurysm, while at the same time having a structure that is soft and flexible enough not to rupture aneurysms, especially small wide-necked aneurysms. Summary of the Invention

[0011] According to one aspect of the medical devices and endovascular medical procedures of the present disclosure, the vaso-occlusive device comprises an elongated vaso-occlusive device (e.g., 0.5-100 cm in length) configured for implantation into an aneurysm sac. The vaso-occlusive devices disclosed herein are particularly well suited for, but are not limited to, being configured and used to treat small, wide-necked aneurysms. Although the devices disclosed herein are described as vaso-occlusive devices for occluding vascular cavities such as aneurysms, the embodiments disclosed herein are not limited to being vaso-occlusive devices, but may be any medical device having the same or similar structure as the disclosed vaso-occlusive devices. For example, the medical device may be any suitable thrombus removal device, stent retriever, embolic filter, stent delivery system, other implant device, guidewire, endovascular device or other medical device.

[0012] Vascular occlusion devices typically have a delivery configuration (having a primary shape) when constrained within a delivery catheter, and a deployed configuration (having a secondary shape different from the primary shape) when released from the delivery catheter into the aneurysm sac.

[0013] The vaso-occlusive device includes a primary coil formed of wire having a primary configuration in a constrained state. For example, the primary configuration can be the shape of the coil when constrained within a delivery catheter, such as a helical coil shape or a linear shape. The vaso-occlusive device is also configured to assume a secondary configuration in a relaxed, unconstrained state, such as when the coil is released from the delivery catheter without an external force acting on the coil.

[0014] The secondary configuration of the vaso-occlusive device comprises a plurality of primary loops and a distal tethering loop that is specifically sized and shaped to minimize the risk of dislodgement during deployment and facilitate long term retention after placement in the aneurysm. The primary loops include a distal primary loop that is the most distal of the primary loops. The distal primary loop has a proximal end and a distal end. The proximal end is connected to the other primary loops and the distal end is connected to the distal tethering loop. Each of the individual loops of the distal primary loops lies substantially in a first plane and a plane parallel to the first plane, such that each of the individual loops lies within a respective substantially two dimensional surface. The distal primary loop has a perimeter that is the length of the wire that forms the distal primary loop from the proximal end to the distal end of the primary loop. The distal primary loop typically has a substantially circular shape or a substantially arc shape. As used herein, the term "substantially circular shape" or "substantially arc shape" refers to a shape that is primarily circular.

[0015] The distal tether loop is typically the most distal end of the vaso-occlusive device and is therefore the first element of the vaso-occlusive device inserted into the aneurysm during deployment of the vaso-occlusive device. The distal tether loop has a substantially triangular shape and is substantially smaller in size than the distal primary loop. As used herein, the term "substantially triangular shape" refers to a shape having three distinct sides joined at three vertices, which may be sharp corners or arcs forming fillet vertices joining the sides. The distal tether loop has an overall length that is the length of the wire forming the distal tether loop. In other words, the length of the three sides of the substantially triangular shape and the length of any one or more arcs that form the fillet vertices of the substantially triangular shape. In one embodiment, the distal tether loop has an overall length that is 25% to 75% of the circumference of the distal primary loop. In an alternative embodiment of the vaso-occlusive device, the distal tether loop can have an overall length that is 40% to 60% of the circumference of the distal primary loop. In yet another alternative embodiment of the vaso-occlusive device, the distal anchoring loop can have a total length that is less than 60% of the circumference of the distal primary loop.

[0016] The distal anchoring loop is disposed within a projection of the distal primary loop, in other words, the distal anchoring loop is disposed within (e.g., in the same plane as) the outer periphery of the distal primary loop, or within a perpendicular projection of (e.g., the distal anchoring loop may be parallel to the first plane and outside the respective plane of the distal primary loop).

[0017] In another aspect of the vaso-occlusive device, the secondary configuration can also include a body portion proximal to the primary portion. The body portion can include a coil formed from a wire and extending proximally from the primary portion. For example, the body portion can be a helical coil or other suitable shape for filling the aneurysm.

[0018] In another embodiment, the substantially triangular shape of the distal anchoring loop may be formed from a base and two sides connected to the base, each of the sides being connected to the base by a rounded apex, and the angle between the base and each of the other sides is between 15° and 75°. Alternatively, the angle between the base and each of the other sides may be between 25° and 50°.

[0019] In yet another aspect, the beginning of the distal tether loop where it joins the distal primary loop is between the 10:00 and 11:00 positions, with the longitudinal axis of the primary configuration of the coil at the 12:00 position. This feature provides increased stability during deployment and retention and prevents dislodging from the aneurysm.

[0020] In another aspect, the distal tether loop can be connected to the distal primary loop via a transition segment, such that the beginning of the distal tether loop is where the distal tether loop is connected to the transition segment, which can be used to position the distal tether loop outside of the plane of the distal primary loop, as described herein.

[0021] In yet another embodiment of the vaso-occlusive device, the distal anchoring loop can be positioned out of the plane of the distal primary loop, for example, the distal anchoring loop can be parallel to the first plane and disposed outwardly relative to the interior of the vaso-occlusive device from all of the planes of the individual loops of the distal primary loop.

[0022] In yet another embodiment, the vaso-occlusive device can further include a second distal anchoring loop distal to the distal anchoring loop, which can have substantially the same shape and size as the distal anchoring loop and can be disposed parallel to the distal anchoring loop.

[0023] In another feature of the vaso-occlusive device, the primary configuration can include an elongated helical coil that provides the vaso-occlusive device with good flexibility and a relatively compact configuration upon deployment within the delivery catheter, while also providing sufficient stiffness to eject the device from the delivery catheter.

[0024] In yet another aspect, the wire can be formed from a shape memory material, in which case the secondary configuration can be set by winding the wire around a mandrel and heat treating the mandrel-wrapped wire.

[0025] In another feature of the vaso-occlusive device, each of the primary loops may have an average outer diameter of 10-90 percent of the diameter of the aneurysm that the vaso-occlusive device is designed to treat. Alternatively, each of the primary loops may have an average outer diameter of 55-85 percent of the diameter of the aneurysm that the vaso-occlusive device is designed to treat. These size limitations of the primary loops provide good framing of the aneurysm and provide shape stability to the vaso-occlusive device upon deployment.

[0026] In an additional aspect of the vaso-occlusive device, the primary portion can include a pyramidal shaped portion formed from primary loops, each of which includes a winding of wire forming a closed loop of greater than 360°, with the multiple primary loops arranged in a pyramidal shape such that each primary loop is located on a different side of the pyramidal shape. The secondary configuration provides a balanced solution between shape stability and softness, such that the vaso-occlusive device has a stable shape that prevents dislodging during deployment and retention and provides effective framing of the aneurysm, while also being soft / flexible enough to avoid aneurysm rupture. The pyramidal shape has the inherent ability to effectively dissipate forces applied to its apex, thereby reducing the risk of excessive forces acting on the aneurysm wall that could rupture the aneurysm.

[0027] In yet another embodiment, the primary loops can be tapered to provide inward loops. Each of the primary loops has an outer circumference that tapers outward from the interior of the pyramidal portion. The outwardly tapered diameter causes each loop or turn of the distal coil to face inward. In other words, the surface of the loop faces inward toward the geometric interior of the pyramidal shape of the pyramidal portion. For example, for a primary loop in a helical coil shape, the diameter of the loop increases outward such that the inner portion of the coil loop has a smaller diameter than the outer portion of the coil loop. The inward loops tend to avoid dislodging from the aneurysm during deployment and retention, and the pyramidal configuration of the distal coil also provides shape stability to effectively frame the aneurysm while also exhibiting a soft, flexible structure that avoids excessive wall forces that may rupture the aneurysm. In yet another embodiment, each of the primary loops can be connected to the adjacent primary loop or loops by a transition segment of wire between each primary loop and the adjacent primary loop or loops.

[0028] In yet another aspect, the secondary configuration can also have a body portion proximal to the pyramidal portion. The body portion can include a coil formed from a wire and extending proximally from the primary portion. For example, the body portion can be a helical coil or other suitable shape for filling an aneurysm.

[0029] In yet another aspect, each of the primary loops can include at least 1+1 / 3 loops or turns (480° turns), or 1+2 / 3 to 2+2 / 3 loops (960° turns). In yet another feature, the primary loops can overlap during the transition from one primary loop to an adjacent primary loop. In other words, the transition segment overlaps the coils as it extends from one distal coil to a subsequent adjacent coil.

[0030] Also disclosed are methods of manufacturing any of the vaso-occlusive devices described herein, and mandrels used to manufacture the vaso-occlusive devices. In one method of manufacturing a vaso-occlusive device using a mandrel, a mandrel for forming the vaso-occlusive device is provided. The mandrel includes a support member and a plurality of primary loop posts extending from and spaced around the support member. The primary loop post includes a distal primary loop post having a first end connected to the support member and a second end extending away from the support member. The distal primary loop post has a first circumference for winding a wire around the distal primary loop post. The mandrel also has a distal anchoring loop sub-mandrel coupled to the second end of the distal primary loop post. The distal anchoring loop sub-mandrel is configured to form a substantially triangular shaped loop from the wire wound around the distal anchoring loop sub-mandrel.

[0031] A coil formed of wire having a primary configuration is then wound around the mandrel. The wire is wound around each of the primary loop posts to form a primary portion of the vaso-occlusive device including a plurality of primary loops. The plurality of primary loops includes a distal primary loop formed by winding the wire around a distal primary loop post. The distal primary loop is the most distal primary loop of the vaso-occlusive device and has a proximal end, a distal end, and a perimeter from the proximal end to the distal end. The wire is also wound around a sub-mandrel of the distal anchoring loop to form a distal anchoring loop connected to the distal end of the distal primary loop. The distal anchoring loop has a substantially triangular shape with a total length between 25% and 75% of the perimeter of the distal primary loop. The distal anchoring loop is disposed within a projection of the distal primary loop.

[0032] In another aspect of the method of manufacturing a vaso-occlusive device, the mandrel further includes a body post extending from the support member. The method further includes winding a wire around the body post forming a body portion of the vaso-occlusive device proximal to the primary portion. The body portion can include a helical coil extending proximally from the primary portion.

[0033] In another aspect of the method, the primary section can include a pyramidal shaped section formed from primary loops. Each primary loop post has a longitudinal axis oriented such that a respective plane perpendicular to the respective longitudinal axis has an intersection line that forms a pyramidal shape with an apex distal to the distal coil post. When wire is wound around each of the primary loop posts to form a closed loop that is greater than 360°, the resulting multiple primary loops are arranged in a pyramidal shape such that each primary loop is on a different side of the pyramidal shape.

[0034] In yet another aspect of the method, the support member may be a central spherical element, and as the wire is wound around the mandrel, transition segments between adjacent primary loops are formed by traversing the wire along the spherical element.

[0035] In yet another aspect of the method, each of the primary loop posts can have a cross-sectional diameter that flares outward as the primary loop post moves away from the spherical element, such that each of the primary loops has a perimeter that flares outward from the interior of the (possibly pyramidal) primary portion.

[0036] In another aspect of the method, the pyramidal shape is a polyhedral shape formed from an n-sided polygonal base and n side faces that connect to an apex.

[0037] In another aspect of the method, the substantially triangular shape of the distal anchoring loop is formed from a base and two sides connected to the base, each of the sides being connected to the base by a rounded apex, and the angle between the base and each of the other sides is between 15° and 75°. Alternatively, the angle between the base and each of the other sides may be between 25° and 50°.

[0038] In yet another aspect of the method, the total length of the distal anchoring loop is between 40% and 60% of the circumference of the distal primary loop. In another feature of the method, the beginning of the distal anchoring loop where it joins the distal primary loop is between the 10:00 and 11:00 positions, with the longitudinal axis of the primary configuration of the coil at the 12:00 position.

[0039] In another aspect of the method, the distal anchoring loop is connected to the distal primary loop through a transition segment, and the beginning of the distal anchoring loop is where the distal anchoring loop joins the transition segment.

[0040] In yet another aspect of the method, the distal anchoring loop may be out of the plane of the distal primary loop, for example, the distal anchoring loop may be parallel to a first plane and outwardly disposed relative to the interior of the vaso-occlusive device from all planes of the distal primary loop.

[0041] In another aspect of the method, the primary configuration is a coil configuration in a constrained state, the primary configuration including an elongated helical coil.

[0042] In yet another aspect of the method, the wire can be formed from a shape memory material. The method further includes heat treating the mandrel wound wire to set a secondary configuration of the vaso-occlusive device. In another aspect, the secondary configuration is a relaxed, unconstrained configuration of the coil.

[0043] In yet another aspect of the method, each of the primary loops can have an average outer diameter of 10 to 90 percent of the diameter of the aneurysm that the vaso-occlusive device is designed to treat. Alternatively, each of the primary loops can have an average outer diameter of 55 to 85 percent of the diameter of the aneurysm that the vaso-occlusive device is designed to treat.

[0044] In yet another aspect of the method, the vaso-occlusive device can be wound in the reverse direction; that is, the wire is first wound around the body post to form the body portion. The wire is then wound around each of the primary loop posts to form respective closed loops greater than 360°, and the resulting primary loops are arranged in a pyramidal shape, with each primary loop located on a different side of the pyramidal shape. The wire is then wound around the distal anchoring post to form the distal anchoring loop. The method can include any of the other features and aspects described herein. In fact, the steps of the method for forming the vaso-occlusive device can be performed in any suitable order.

[0045] In further aspects of the methods of manufacturing a vaso-occlusive device, the vaso-occlusive device can have any one or more of the aspects and features disclosed herein.

[0046] In a further aspect of the devices disclosed herein, the vaso-occlusive devices disclosed herein can be part of a vaso-occlusive system that includes a vaso-occlusive assembly and a delivery assembly. For example, the vaso-occlusive assembly can include any of the vaso-occlusive devices described herein and a pusher member detachably coupled to a proximal end of the vaso-occlusive device. The pusher member is configured to enable a clinician to advance the vaso-occlusive device along a delivery catheter through a patient's vasculature to a target site, such as an aneurysm, to be treated with the vaso-occlusive device and push the vaso-occlusive device out of the distal end of the delivery catheter to deploy the vaso-occlusive device.

[0047] In yet another aspect, the vaso-occlusive assembly can also include a detachment device that releasably couples the pusher member to the vaso-occlusive device. For example, the detachment device can include an electrolytic detachment, a mechanical connector, a thermally actuated detachment, a dissolution detachment, or the like. The delivery assembly can include a delivery catheter through which the vaso-occlusive device can be introduced in its compact delivery configuration. The delivery assembly can also include a guidewire for guiding the delivery catheter to a target implantation site within the patient's vasculature, such as an aneurysm. The guidewire is then removed and the vaso-occlusive device is advanced through the delivery catheter to the target implantation site.

[0048] Methods of using any of the vascular occlusion devices or other medical devices described herein are also disclosed. In one method, the vascular occlusion device is inserted into and advanced through a delivery catheter device in its primary configuration, which is a compact delivery configuration. The delivery catheter is first inserted into and advanced through the patient's vasculature, with the distal end of the delivery catheter positioned at a target anatomical body cavity, such as an aneurysm in this example. It should be understood that the target anatomical body cavity may be any suitable anatomical site within the vasculature where the vascular occlusion device is deployed. If a guidewire is utilized, the guidewire is first inserted into the patient's vasculature and advanced through the vasculature to the site of the aneurysm. The delivery catheter is then advanced along the guidewire to the aneurysm, after which the guidewire is removed.

[0049] The vaso-occlusive device is then inserted into the delivery catheter in its primary configuration and advanced along the delivery catheter to the target anatomical body cavity. The vaso-occlusive device is then pushed distally out of the delivery catheter, such as using a pusher member. As the vaso-occlusive device is pushed out of the delivery catheter, the distal tethering loop becomes the first configuration of the vaso-occlusive device inserted into the target anatomical body cavity. As the distal tethering loop exits the delivery catheter and enters the body cavity, it assumes its secondary configuration, including a substantially triangular shape. As the vaso-occlusive device continues to be pushed out of the delivery catheter, the distal primary loop enters the body cavity. The size and shape of the distal tethering loop are configured to maintain or "tether" the vaso-occlusive device within the body cavity as the device is deployed into the target anatomical body cavity, thereby preventing dislodgment with no or minimal manipulation by the clinician. As the vaso-occlusive device continues to be released from the delivery catheter and inserted into the body lumen, each of the primary loops may be inserted into the body lumen and expand towards their respective secondary configurations, effectively framing and filling the body lumen with a stable, yet flexible structure, thereby providing excellent retention within the body lumen while avoiding damaging or rupturing the intraluminal tissue. Once the entire vaso-occlusive device is inserted into the aneurysm sac, it may be detached from the pusher member, such as by activating or actuating a detachment device.

[0050] In some cases, a single vaso-occlusive device may be sufficient to fill and occlude the aneurysm, and if multiple vaso-occlusive devices are required, the process can be repeated to deliver a sufficient number of vaso-occlusive devices to fill and occlude the aneurysm.

[0051] Thus, there is a need for a vaso-occlusion device that can mitigate the problem of dislodgement during placement and retention, provide effective framing of the aneurysm, and at the same time has a structure that is soft and flexible enough not to rupture aneurysms, especially small wide-necked aneurysms.

[0052] Other and further aspects and features of embodiments of the disclosed invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. [Brief description of the drawings]

[0053] The drawings illustrate the design and utility of various aspects of the devices and methods disclosed herein, with similar elements being commonly numbered. It should be noted that the drawings are not drawn to scale, and elements of similar structure or function are indicated by similar numbers throughout the drawings. It should also be noted that the drawings are intended only to facilitate the description of various aspects of the disclosed technology. They are not intended as an exhaustive description of the technology or as a limitation on the scope of the technology, which is defined only by the appended claims and their equivalents. Furthermore, an exemplary embodiment of the disclosed technology need not have all aspects or advantages disclosed or described herein. An aspect or advantage described in connection with a particular embodiment of the disclosed technology is not necessarily limited to that embodiment, and may be implemented in any other embodiment, even if not so illustrated. To better understand how the above and other advantages and objects of the technology are obtained, a more particular description of the technology, briefly described above, will be made by reference to specific examples thereof illustrated in the accompanying drawings. The present technology will be explained and described with additional specificity and detail through the use of the accompanying drawings, with the understanding that the drawings and corresponding description illustrate only illustrative embodiments of the disclosed technology and therefore should not be considered as limiting its scope.

[0054] [Figure 1] FIG. 1 is a side cross-sectional view of a delivery catheter deploying a vaso-occlusive device, showing the vaso-occlusive device detached upon deployment of the distal-most loop. [Diagram 2] FIG. 2 is a side cross-sectional view of a delivery catheter deploying a vaso-occlusive device, showing the vaso-occlusive device detaching upon deployment of loops subsequent to deployment of the distal-most loop. [Diagram 3] FIG. 3 is a cross-sectional side view of a delivery catheter for deploying a vascular occlusion device and a balloon actuated catheter for use in remodeling or indwelling techniques. [Figure 4] FIG. 4 is a cross-sectional side view of a delivery catheter that deploys a vaso-occlusive device and stent used in the deployment technique. [Diagram 5] FIG. 5 is a cross-sectional side view of a delivery catheter that deploys a vaso-occlusive device and a stent used in the Recross technique. [Figure 6] FIG. 6 is a side perspective view of a vaso-occlusive device disclosed herein, shown in a relaxed, deployed configuration. [Figure 7] FIG. 7 is a simplified top perspective view of the intersecting planes of the three distal coils of FIG. 6 that form the pyramidal shaped portion of the triangular pyramidal shaped vaso-occlusive device. [Figure 8] FIG. 8 is a simplified top perspective view of the intersecting planes of four distal coils forming the pyramidal shaped portion of a square pyramidal shaped vaso-occlusive device. [Figure 9] FIG. 9 is a side view of a primary loop post for forming a primary loop of a vaso-occlusive device, illustrating the taper angle for the primary loop. [Figure 10] FIG. 10 is a side perspective view of one example of an alternative pyramidal shaped portion of the vaso-occlusive device of FIG. 6 in which the primary loop has varying diameters and varying numbers of turns. [Figure 11] FIG. 11 shows force and displacement diagrams for various configurations of vaso-occlusive devices. [Figure 12] FIG. 12 is a diagram showing the geometry of a distal anchoring loop disclosed herein. [Figure 13] 13 is a side view of the distal anchoring loop and first primary loop of the vaso-occlusive device of FIG. 6. FIG. [Figure 14]Figure 14A is a side perspective view of the vaso-occlusive device of Figure 6 showing the location of the beginning of the distal tethering loop at approximately the 10:00 o'clock position. Figure 14B is a side perspective view of an alternative design of the vaso-occlusive device of Figure 6 having the location of the beginning of the distal tethering loop at approximately the 12:00 o'clock position. [Figure 15] FIG. 15 is a side perspective view of an exemplary mandrel for manufacturing the vaso-occlusive device of FIG. [Figure 16] FIG. 16 is a side perspective view of an exemplary mandrel for manufacturing a vaso-occlusive device having four distal coils that form a primary portion of the vaso-occlusive device having a square pyramidal shape. [Figure 17] Figure 17A is a top perspective view of the mandrel of Figure 15 around which wire is wrapped to produce the vaso-occlusive device of Figure 6. Figure 17B is a side perspective view of the mandrel of Figure 17A around which wire is wrapped to produce the vaso-occlusive device of Figure 6. [Figure 18] FIG. 18 is a flow chart illustrating a method of manufacturing a vaso-occlusive device described herein using a mandrel described herein. [Figure 19] Figure 19A is a cross-sectional side view of an initial deployment of the vaso-occlusive device of Figure 6 with the distal tethering loop inserted into the aneurysm, and Figure 19B is a cross-sectional side view of the vaso-occlusive device of Figure 6 upon deployment of the distal tethering loop and the first primary loop. [Figure 20] Figure 20A is a cross-sectional side view of a vascular occlusion system including the vascular occlusion device of Figure 6 in a constrained delivery configuration within a delivery catheter, and Figure 20B is a cross-sectional side view of the vascular occlusion system of Figure 20A with the vascular occlusion device deployed from the delivery catheter in its expanded deployed configuration. [Figure 21] FIG. 21 is a cross-sectional side view showing a guidewire being advanced into a portion of a patient's vasculature to the location of an aneurysm. [Figure 22] 22 is a cross-sectional side view of the guidewire of FIG. 21 and a patient's vasculature with a delivery catheter advanced over the guidewire. [Diagram 23]FIG. 23 is a cross-sectional side view showing the vaso-occlusive system of FIGS. 20A and 20B being advanced within the delivery catheter of FIG. 22 to deploy a vaso-occlusive device within an aneurysm. [Figure 24] 24 is a cross-sectional side view of the vaso-occlusive system of FIGS. 20A and 20B with the vaso-occlusive device deployed within the aneurysm from the delivery catheter shown in FIG. [Diagram 25] FIG. 25 is a flow chart of an exemplary method for deploying the vaso-occlusive devices disclosed herein within an aneurysm using the vaso-occlusive system of FIGS. 20A and 20B. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0055] 6, an example of a vascular occlusion device 100 as disclosed herein is shown. This example of a vascular occlusion device is described in detail herein as a vascular occlusion device for occluding an aneurysm, however, it should be understood that the device is not limited to being configured for deployment within an aneurysm, but may be sized and configured to occlude any suitable anatomical body cavity. Furthermore, the device is not limited to being an occlusion device, but may be any suitable medical device, such as a thrombus removal device, a stent retriever, an embolic filter, a stent delivery system, other implantation device, a guidewire, or an intravascular device.

[0056] FIG. 6 shows the vaso-occlusive device 100 in the secondary configuration in a relaxed, unconstrained state. In other words, FIG. 6 shows the vaso-occlusive device 100 when no external forces are acting on the vaso-occlusive device 100. The secondary configuration of the vaso-occlusive device 100 has a primary portion 104, a base portion 106, and a distal tethering loop 105. The primary portion 104 is distal to the body portion 106, and the distal tethering loop 105 is distal to the primary portion 104. As used herein, the terms "distal" and "proximal" refer to the vaso-occlusive device 100 as it is intended to be deployed, with the term "distal" referring to being located toward the end of the device 100 that is inserted first and the term "proximal" referring to being located toward the end of the device 100 that is inserted last.

[0057] Vaso-occlusive device 100 includes a coil formed of wire 102 having a primary configuration in a constrained configuration. For example, the constrained configuration may be an elongated helical coil when wire 102 is constrained within a delivery catheter (see FIG. 20A). Typically, the primary shape has a longitudinal length of between 1 cm and 70 cm. Wire 102 may be made from any suitable material, but is typically formed from a radiopaque shape memory material such as platinum group metals, including platinum, rhodium, palladium, and rhenium, as well as tungsten, gold, silver, tantalum, and alloys thereof.

[0058] Distal tether loop 105 of the secondary configuration of vaso-occlusive device 100 is formed by the distal-most portion of vaso-occlusive device 100 in the primary configuration (see FIG. 20A). Primary portion 104 of the secondary configuration of vaso-occlusive device 100 is formed by the portion of vaso-occlusive device 100 in its primary configuration that is immediately proximal to the distal tether loop (see FIG. 20A).

[0059] The primary portion 104 includes a number of primary loops 108 wound from the wire 102. In the example shown in FIG. 6, the primary portion 104 includes three primary loops 108a, 108b, 108c. The first primary loop 108a (also referred to as the "distal primary loop") is the most distal primary loop 108, the second primary loop 108b is immediately proximal to the first primary loop 108a, and the third primary loop 108c is immediately proximal to the second primary loop 108b (i.e., the most proximal primary loop 108). The primary loops 108 are connected end-to-end, with the proximal end of the first primary loop 108a connected to the distal end of the second primary loop 108b, and the proximal end of the second primary loop 108b connected to the distal end of the third primary loop 108c.

[0060] In the example shown in FIG. 6, the primary portion 104 includes three primary loops 108a, 108b, 108c arranged to form a three-sided pyramidal shape, also referred to as a triangular pyramid. The pyramidal shape in the example of FIG. 6 is called a triangular pyramid because the base of the pyramidal shape (the primary loops 108 do not include a distal coil at the base of the pyramidal shape, but the body portion 106, described below, can form the base portion of the pyramidal shape) is triangular, and each coil 108 is located on each side of the triangular pyramid. The respective planes in which the respective turns / loops of each primary loop 108 are located are not parallel to each other, but intersect each other. As shown in FIG. 6, the intersecting planes of the primary loops 108 can be simplified to form a tetrahedron, more specifically, a triangular pyramid. The vaso-occlusive device 100 in FIG. 6 is an example, and is not limited to the primary loops 108 forming a triangular pyramid shape, but may have other suitable pyramid shapes, such as n primary loops 108 forming a pyramid having a polygonal base with n sides and n sides connected to an apex. For example, the vaso-occlusive device 100 may have a primary loop 108 on each side of a pyramid shape, such as a regular pyramid with a square base and four sides, a regular pyramid with a square base and four sides, or a pentagonal pyramid with a pentagonal base and five sides. As shown in FIG. 7, the primary portion 104 may have four primary loops 108 on each side arranged to form a regular pyramid with a square base and four sides.

[0061] 6, each primary loop 108 includes windings that form a closed loop of more than 360°, i.e., at least a complete closed loop. In the illustrated vaso-occlusive device 100, each primary loop 108 includes 1+1 / 3 loops (also referred to as "turns") of windings, which corresponds to 480° of windings. Alternatively, each primary loop 108 can have at least 1+1 / 3 turns, or between 1+1 / 3 turns (480°) and 2+2 / 3 turns (960°).

[0062] The windings of each primary loop 108 may also have a width that tapers outwardly from a reference point inside the primary portion 104. For the helical coil shown in the example of FIG. 6, the width of each primary loop 108 is the diameter of the coil. If the primary loop 108 is wound into a variety of shapes, such as a square, pentagon or other polygon or curved shape, the width may be an average width, such as the average of the maximum and minimum widths drawn through the geometric center of the shape. Returning to the example of FIG. 6, the diameter of each primary loop 108 is tapered such that the diameter of the outer portion of the coil 108 is greater than the diameter of the inner portion of the coil 108. This can be better explained with reference to a cross section of a cylindrical post around which the primary loop 108 is wound, as shown in FIG. 9. The post has a diameter that tapers outwardly from the inner portion of the post to the outer portion of the post, as shown in FIG. 8. The angle 114 of the taper of the post defines the angle of taper of the primary loop 108 in the secondary configuration of the vasoocclusive device 100. Due to the outwardly tapered diameter, each loop or turn of the primary loop 108 faces inwardly. In other words, the surfaces of the loop face inwardly toward the geometric interior of the pyramidal shape of the primary portion 104.

[0063] Each of the primary loops 108 has a diameter (defined as the diameter of the innermost loop of each primary loop 108) that is 10-90 percent of the diameter of the aneurysm (or other anatomical body cavity to be filled by vaso-occlusive device 100) that vaso-occlusive device 100 is designed to treat. Alternatively, the diameter of each primary loop 108 may be 55-85 percent of the diameter of the aneurysm that vaso-occlusive device 100 is designed to treat.

[0064] In alternative designs of the vaso-occlusive device 100, the primary loops 108 can have different diameters and / or different numbers of turns of the wire 102, as shown in Figure 9. As shown in Figure 10, the first primary loop 108a has a larger diameter and more turns of the wire 102 (3 turns, i.e., 1080°) than the second primary loop 108b, which has 1+2 / 3 turns (600°). The third primary loop 108c also has a larger diameter (same diameter as the first primary loop 108a, but 1+2 / 3 turns (600°)) than the second primary loop 108b.

[0065] The distal primary loop 108a has a perimeter from its proximal end to its distal end (i.e., the length of the wire 102 that forms the distal primary loop 108a). For a circular distal primary loop 108a, the perimeter is the circumference or arc length equal to 2πr(Θ / 360), where "r" is the radius of the arc and "Θ" is the angle of the arc. The individual turns of the distal primary loop 108a lie substantially in respective ones of a plurality of parallel planes, including a first plane, such that each loop lies substantially on a two-dimensional surface.

[0066] The primary portion 104 also includes transition segments 110 for each of the wires 102, which are between and connect adjacent primary loops 108. Each transition segment 110 extends from the end of one primary loop 108 to the beginning of the subsequent primary loop 108. That is, transition segment 110a extends from the proximal end (ending) of primary loop 108a to the distal end (starting) of primary loop 108b, and transition segment 110b extends from the proximal end (ending) of primary loop 108b to the distal end (starting) of primary loop 108c. There is also a transition segment 112 from the proximal end of the winding of the last primary loop 108c to the distal end of the body portion 106, and a distal anchoring loop ("DAL") transition segment 111 from the proximal end of the distal anchoring loop 105 to the distal end of the first primary loop 108a.

[0067] The distal tether loop 105 is at the most distal end of the vaso-occlusive device 100 and is the first element of the vaso-occlusive device 100 inserted into a body cavity (e.g., an aneurysm) during deployment of the vaso-occlusive device. The distal tether loop 105 has a substantially triangular shape and is substantially smaller in size than the first (i.e., distal) primary loop 108a. The distal tether loop 105 has a distal tip 107 that marks the tip of the vaso-occlusive device 100. That is, the distal tip 107 is the most distal end of the vaso-occlusive device 100. The triangular shape of the distal tether loop 105 is more difficult to deform and / or displace during deployment when assuming its secondary configuration within an aneurysm than other shapes, such as circles and squares, as shown in FIG. 11 .

[0068] 12, the substantially triangular shape of the distal anchoring loop 105 is formed by a base "C" and two sides "E" and "A" connected to the base "C". Each of the sides "E" and "A" is connected to the base by a rounded apex, and the angle "Θ" between the base "C" and each of the sides "E" and "A" is between 15° and 75°. Alternatively, the angle "Θ" between the base "C" and each of the sides "E" and "A" may be between 25° and 50°.

[0069] The distal tether loop 105 has an overall length that is the length of the wire 102 that forms the distal tether loop 105. As shown in FIG. 12, the overall length of the distal tether loop 105 shown in FIG. 6 is the sum of the lengths of the three sides of the substantially triangular shape (A+C+E) and the length of one or more of the arcs that form the fillet apex of the substantially triangular shape (B+D). As shown in FIG. 12, the distal tether loop 105 can have an overall length "F" that is 25%-75% of the circumference of the distal primary loop 108a, or the distal tether loop 105 can have an overall length that is 40%-60% of the circumference of the distal primary loop 108a, or the distal tether loop 105 can have an overall length that is less than 60% of the circumference of the distal primary loop 108a.

[0070] As shown in Fig. 6, the distal anchoring loop 105 is disposed within the projection of the distal primary loop 108a. In other words, the distal anchoring loop 105 is disposed within the outer periphery of the distal primary loop 108a (e.g., in the same plane) or within a perpendicular projection of the outer periphery of the distal primary loop 108a (e.g., the distal anchoring loop may be parallel to a first plane and out of the plane of the distal primary loop 108a). The partial side view of Fig. 13 shows the distal anchoring loop 105 disposed parallel to and out of the plane of the distal primary loop 108a.

[0071] 14A and 14B show a comparison of vaso-occlusive devices 100 with different locations of the beginning of the distal tether loop 105. The beginning of the distal tether loop 105 is the location where the distal tether loop 105 joins the distal primary loop 108a. The vaso-occlusive device 100 of FIG. 14A has the beginning 118 of the distal tether loop 105 between approximately the 10:00 and 11:00 positions relative to the longitudinal axis 120 of the primary configuration of the wire 102, which is at the 12:00 position. As a result, the distal primary loop 108a begins at approximately this same position. This is in contrast to the vaso-occlusive device 100a of FIG. 14B, where the beginning 118 of the distal tether loop 105 is at approximately the 12:00 position relative to the longitudinal axis 120. As a result of the different starting points of the distal tethering loops 105, the distal primary loop 108a of the device 100 of FIG. 14A is longer than the distal primary loop 108a of the device 100a of FIG. 14B. This longer distal primary loop 108a of the vaso-occlusive device of FIG. 14A provides better initial framing of the device 100 during deployment within the aneurysm than the shorter distal primary loop 108a of the vaso-occlusive device of FIG. 14B. Through empirical testing, it has been found that starting points 118 of the distal tethering loops 105 between approximately the 10:00 and 11:00 positions relative to the longitudinal axis 120 provide better initial framing of the aneurysm during deployment than starting points 118 at other positions that provide different lengths of the distal primary loop 108a, such as the 12:00-3:00, 3:00-6:00, and 6:00-9:00 positions.

[0072] As shown in FIG. 6, the body portion 106 includes a winding of the wire 102 extending proximally from the primary portion 104. The body portion 106 can extend from an imaginary base of the pyramidal shape of the primary portion 104. In the example shown in FIG. 6, the body portion 106 is a helical coil extending proximally from the pyramidal portion 102. The body portion 106 can have a constant diameter, or alternatively, the body portion 106 can have a diameter that tapers outwardly or inwardly as it extends proximally from the primary portion 104. The body portion 106 comprises at least one complete loop of the wire 102. The body portion 106 does not have a maximum number of windings and can include any suitable number of turns, such as 1-20 turns. The body portion 106 shown in FIG. 6 has approximately 3-4 complete turns of the wire 102.

[0073] 15, an exemplary mandrel 200 for manufacturing vaso-occlusive device 100 using method 300 (described below) is shown. Mandrel 200 is used to wind wire 102 to form the secondary configuration of vaso-occlusive device 100. Mandrel 200 is configured to form vaso-occlusive device 100 including primary portion 104 having a triangular pyramidal shape, distal anchoring loop 105, and base portion 106.

[0074] The mandrel 200 has a central spherical element 202 (also referred to as a "support member") from which extend outwardly a number of primary loop posts 204. Each primary loop post has a first end connected to the spherical element 202, a second end extending away from the spherical element 202, and an outer circumference for winding a wire onto the respective primary loop post 204. The primary loop posts 204 are configured to form the primary loops 108 of the vaso-occlusive device 100. Thus, primary loop post 204a forms distal primary loop 108a, primary loop post 204b forms primary loop 108b, primary loop post 204c forms primary loop 108c, and so on, depending on the number of primary loop posts 204 and primary loops 108. The primary loop posts 204 are angularly spaced about the spherical element 202. In the illustrated mandrel 200, the primary loop posts 204 are equally spaced such that the respective longitudinal axes of each primary loop are equally angularly spaced around the spherical element 202. Thus, in the case of three primary loop posts 204, the primary loop posts 204 are spaced 120° apart.

[0075] The periphery of each primary loop post 204 has a cross-sectional diameter that flares outward as the primary loop post 204 extends away from the spherical element 202, as shown in Figure 9, which shows a side view of one of the primary loop posts 204. The taper angle 114 of the primary loop posts 204 is the same as the taper of the primary loops 108 described herein. The longitudinal axis of each primary loop post 204 is also tilted distally such that respective planes perpendicular to the respective longitudinal axes are non-parallel and non-perpendicular, with the planes having intersections that form a pyramidal shape with an apex distal to the primary loop post 204.

[0076] The mandrel 200 also has a distal anchoring loop sub-mandrel 208 coupled to the second end of the distal primary loop post 204a. The distal anchoring loop sub-mandrel 208 can extend outwardly from the second end of the distal primary loop post 204a. The distal anchoring loop sub-mandrel 208 is configured to form the distal anchoring loop 105 from the wire 102 into its generally triangular shaped loop. The distal anchoring loop sub-mandrel 208 is also oriented to set the beginning 118 of the distal anchoring loop 105 between approximately the 10:00 o'clock position and the 11:00 o'clock position relative to the longitudinal axis 120.

[0077] The mandrel 200 also has a body post 206 extending from the spherical element 202. The body post 206 is configured to form the body portion 106 of the vaso-occlusive device 100. In the example shown in Figure 15, the body post 206 extends proximally from the spherical element 202 and perpendicular to the base of the pyramidal shape of the primary portion 104. The body post 206 may be a cylinder having a constant diameter, or alternatively, the body post 206 may taper outwardly or inwardly as it extends from the spherical element 202.

[0078] With the aid of this disclosure, one of ordinary skill in the art will understand how to modify mandrel 200 to be configured to manufacture vaso-occlusive devices 100 including primary portions 104 having other pyramidal shapes as disclosed herein. For example, FIG. 16 illustrates a mandrel 210 configured to manufacture vaso-occlusive devices 100 including primary portions 104 having a regular square pyramidal shape. This mandrel 210 is the same as or substantially similar to mandrel 200, except that mandrel 210 has four primary loop posts 204 equiangularly spaced about a central spherical member 202.

[0079] 17A and 17B and the flow chart of FIG. 18, an exemplary method 300 of manufacturing a vaso-occlusive device 100 using a mandrel 200 is shown. A coil formed from a wire 102 having a primary configuration is wound around the mandrel 200. As described herein, the wire 102 may be formed from a shape memory material, and the primary configuration may be the configuration of the wire 102 in a constrained state, such as within a sheath or delivery catheter. The primary configuration may have any suitable shape, such as a helical coil.

[0080] In step 302, the wire 102 is wrapped around the distal anchoring loop post 208 to form the distal anchoring loop 105. In step 304, the wire 302 is traversed to the distal end of the first primary loop 108a to form the DAL transition segment 111. In step 306, the wire 102 is wrapped around the first primary loop post 204a in a first direction, wrapping inwardly towards the intersection of the first primary loop post 204a and the spherical element 202. Subsequent wraps begin at the intersection of the post 204 and the spherical element 202 and wrap away from the spherical element 202. As used herein, a "direction" of wrapping is the direction as viewed inwardly along the wrapping axis, toward the attachment of the wrapping post to the central spherical element or other central structure. Thus, the "first direction" shown in the examples of Figures 17 and 17B is a clockwise direction. The wire 102 is wrapped around the first primary loop post 204a as described herein to form the desired number of turns for the first primary loop 108a.

[0081] After wrapping the wire 102 around the first primary loop post 204a, in step 308, the wire 102 traverses along the spherical element 202 to the second primary loop post 204b immediately adjacent to the first primary loop post 108a to form the first transition segment 110a. In step 310, the wire 102 is wrapped around the second primary loop post 204b from the intersection of the second primary loop post 204b with the spherical element 202 in a second direction opposite the first direction (counterclockwise as shown in the example of Figures 16A and 16B). The wire 102 is then wrapped around the second primary loop post 204b as described herein to form the desired number of turns for the second primary loop 108a.

[0082] After wrapping the wire 102 around the second primary loop post 204b, in step 312, the wire 102 traverses along the spherical element 202 to a third primary loop post 204c immediately adjacent to the second primary loop post 204b to form the second transition segment 110a. In step 314, the wire 102 is wrapped around the third primary loop post 204c from the intersection of the third primary loop post 204c with the spherical element 202 in a third direction opposite the second direction (clockwise as shown in the example of Figures 16A and 16B). The wire 102 is then wrapped around the third primary loop post 204c as described herein to form the desired number of turns for the third primary loop 108c.

[0083] Looking at the post 204 as it is wound axially along the axis of rotation, each of the other three posts 204 can represent 1 / 3 of a turn as the coil is wound. Thus, a winding of 1+2 / 3 loops or turns (i.e., 600°) means that as the wire 102 is wound around the post 204, each of the other posts 204, 206 it passes through represents a winding of 1 / 3 loops or turns. Thus, a winding of 1+2 / 3 loops passes through three other posts 204, 206 once, then passes again through two of the three other posts 204, 206, totaling 1+2 / 3 loops. A winding of approximately 2+2 / 3 (960°) passes through each of the other posts 204, 206 twice, then passes again (a third time) through the next two posts. The ends of the coil 108 are positioned so that a full loop (360°) or multiple full loops (360° x an integer) plus another 2 / 3 loop winding will wrap in the opposite direction around the next adjacent post 108. One skilled in the art will readily understand how to determine the exact amount of loops for mandrels having more than three posts 108, such as four posts 108, five posts 108, etc.

[0084] For mandrels 200 having more than three primary loop posts 204, in step 316, the wire 102 is traversed along the spherical element 202 to the next primary loop post 204 immediately adjacent the preceding primary loop post 204 for the next transition segment 110. In step 318, the wire is wrapped around the next primary loop post 204 to form the next primary loop 108, and steps 316-318 are repeated for each additional primary loop post 204. After the wire 102 is wrapped around the last primary loop post 204, in step 320, the wire 102 is transitioned along the spherical element 202 to a body post 206. In step 322, the wire 102 is wrapped around the body post 206 as described herein to form the desired number of turns for the body portion 106.

[0085] In step 324, the wire 102 is heat treated while wound on the mandrel 200 to set the secondary configuration of the vasoocclusive device 100 as if wound on the mandrel 200. In step 326, the wire 102 is removed from the mandrel 200. The wire 102 will assume a secondary configuration having a secondary shape as if wound on the mandrel in a relaxed, unconstrained state.

[0086] It will be appreciated that the vaso-occlusive device 100 may also be formed by winding the wire 102 around the mandrel in the opposite direction. That is, the wire 102 is first wound around the body posts 206 to form the body portion 106. The wire 102 is then wound greater than 360° around each of the primary loop posts 204 to form each of the primary loops 108, and the resulting primary loops 108 are arranged in a pyramidal shape such that each primary loop 108 is on a different side of the pyramidal shape. The wire 102 is then wound around the distal anchoring loop posts 208 to form the distal anchoring loops 105. The wire 102 is also traversed in the reverse order to the method 300 described above to form each of the transition segments 110. In fact, the order of steps of the method 300 may be performed in any suitable order, and the method 300 is not limited to any particular order of steps.

[0087] Thus, disclosed herein is a vascular occlusion device 100 and method 300 for its manufacture that mitigates dislodgement problems during deployment and retention, provides effective framing of the aneurysm, while having a structure that is soft and flexible enough not to rupture the aneurysm, especially small and / or wide-necked aneurysms. The size, shape and location of the distal tethering loop 105 effectively avoids dislodgement of the vascular occlusion device 100 out of the aneurysm during deployment. Figures 19A and 19B show the initial deployment of the vascular occlusion device 100 from the delivery catheter 206 into the aneurysm 440, illustrating how the distal tethering loop 105 functions to avoid dislodgement during insertion. During initial deployment of the vascular occlusion device 100, the distal tip 107 of the distal tethering loop 105 enters the aneurysm 440 first. As shown in Figure 19A, as the distal tethering loop 105 is advanced out of the delivery catheter, it assumes its triangular shape in the secondary configuration of the vascular occlusion device 100. 19B, as vaso-occlusive device 100 continues to be advanced out of delivery catheter 206, distal anchoring loop 105 rotates and moves around as distal primary loop 108a enters the aneurysm and assumes its secondary configuration, but distal tip 107 remains well within aneurysm 440 and does not approach neck 448 of aneurysm 440, thereby minimizing the risk of distal end 107 or other portions of vaso-occlusive device 100 popping out of the aneurysm. Smaller distal anchoring loop 105 mitigates the risks associated with oversized distal primary loop 108a by providing a leading structure that is less susceptible to variations in stiffness of wire 102 and reinforcing sutures (if used). 19B also illustrates how the distal primary loop 108a effectively frames the aneurysm 440, providing sufficient stability to allow the remaining primary loops 108 and base portion 106 to relatively easily deploy to assume the secondary configuration of the vaso-occlusive device 100 within the aneurysm, eliminating the need for the clinician to manipulate the delivery catheter 206 during deployment, thereby eliminating reliance on the clinician's skill for successful deployment.

[0088] Furthermore, the pyramidal shape of the primary loop 108 of the vaso-occlusive device 100 has an inherent ability to effectively dissipate forces applied to its apex, thereby reducing the risk of applying excessive forces to the aneurysm wall that may rupture aneurysms, including small and / or wide-necked aneurysms. Furthermore, the primary loop is tapered inwardly, and the primary loop, which includes a complete closed loop and cross-over segments, folds more tightly than an open loop when deployed within the aneurysm, reducing the risk of dislodgement during deployment and retention. At the same time, the pyramidal shape's inherent ability to dissipate forces applied to its apex does not compromise the stability of the shape. Furthermore, as shown in FIG. 6, the pyramidal shaped vaso-occlusive device 100 is more compact than a cube-shaped vaso-occlusive device having eight coils forming the six faces of the cube. That is, the volume of the pyramidal shaped vaso-occlusive device 100 is smaller than a cube. Additionally, the primary loops 108 of vaso-occlusive device 100 have a smaller diameter than a coil of a cube-shaped vaso-occlusive device having the same or approximately the same overall height as vaso-occlusive device 100. This is because the diameter of each of the primary loops 108 is smaller than the overall height of vaso-occlusive device 100 (e.g., the overall height of vaso-occlusive device 100 is 3.2 mm while the diameter of the primary loops is 2.4 mm), whereas the diameter of the coil of the cube-shaped vaso-occlusive device spans the entire height of the entire vaso-occlusive device (the height is the length of any one of the sides of the cube-shaped vaso-occlusive device).

[0089] 20A and 20B, vascular occlusion device 100 is also a component of a vascular occlusion system 400 that can be used to deploy vascular occlusion device 100 in a body lumen, such as an aneurysm 440 (see FIGS. 21-24). Vascular occlusion system 400 includes a delivery assembly 402 and a vascular occlusion assembly 404. As shown in FIGS. 21 and 22, delivery assembly 402 can include a delivery catheter 406 and an optional guidewire 408. Vascular occlusion assembly 404 includes vascular occlusion device 100 and a pusher member 410 that is detachably coupled to vascular occlusion device 100 via a separation device or joint 412. FIG. 20A shows vascular occlusion assembly 404 after it has been slidably positioned within delivery catheter 406 such that vascular occlusion device 100 is in its compact delivery configuration.

[0090] The delivery catheter 406 is typically an elongated flexible tube and may be, for example, a microcatheter or the like. The delivery catheter 406 comprises an elongated sheath body 414 having a proximal portion 416, a distal portion 418, and a lumen 420 extending from the proximal portion 416 to the distal portion 418. The proximal portion 416 of the delivery catheter 406 typically remains outside the patient's body and is accessible to a clinician when the vascular occlusion system 400 is in use, while the distal portion 418 is sized and dimensioned to reach a remote location in the patient's vasculature and is configured to deliver the vascular occlusion device 100 to a body cavity, such as an aneurysm. The delivery catheter 406 may also have one or more ports 422 in fluid communication with the lumen 420 for introducing fluid into the sheath body 414 or removing fluid from the sheath body. The sheath body 414 can be constructed from a suitable polymeric material, metal and / or alloy, such as polyethylene, stainless steel, or other suitable biocompatible materials or combinations thereof. In some cases, the proximal portion 416 can include a reinforcing layer, such as a braided or coiled layer, to enhance the pushability of the sheath body 414. The sheath body 414 can include a transition region between the proximal portion 416 and the distal portion 418.

[0091] The vaso-occlusive device 100 can be any of the vaso-occlusive devices 100 disclosed herein having any one or more of the features and aspects described herein.

[0092] The vaso-occlusive assembly 404 also includes a pusher member 410. The pusher member 410 is configured to be slidably received within the lumen 420 of the delivery catheter 406. The pusher member 410 has a proximal portion 450, which typically extends proximally beyond the proximal portion 416 of the delivery catheter 406, and a distal portion 452 that is detachably coupled to the proximal end of the vaso-occlusive device 100 via a detachment device 412. The pusher member 410 may be a coil, wire, tendon, conventional guidewire, torque-transmitting cable tube, hypotube, or the like, having sufficient column strength to enable the vaso-occlusive device 100 to be pushed through the distal end 418 of the delivery catheter 406 and into the aneurysm sac 440 (see FIGS. 23 and 24).

[0093] The detachment device 412 provides a severable connection between the pusher member 410 and the vaso-occlusive device 100. The detachment device 412 may include electrolytic detachment, mechanical connectors, thermally actuated detachment, dissolution detachment, or other mechanical, thermal, and hydraulic mechanisms. For example, the detachment device 412 may be an electrolytically degradable segment for electrolytically detaching the vaso-occlusive device 100 from the pusher member 410.

[0094] As shown in Figures 21 and 22, the optional guidewire 408 of the delivery assembly 402 has a proximal end 444 and a distal end 446. As shown in Figure 22, after the guidewire 408 is positioned within the patient's vasculature 442 with the distal end 446 located at the target insertion site, the delivery catheter 406 is advanced over the guidewire 408 with the guidewire 408 positioned within the lumen 420 of the delivery catheter 406. In a "rapid-exchange" configuration of the delivery catheter 406 and guidewire 408, the guidewire 408 extends only through a distal portion of the delivery catheter 406, such as the rapid-exchange lumen. The guidewire 408 is typically used by first advancing the guidewire 408 through the patient's vasculature to the target insertion site (e.g., the neck 448 of the aneurysm to be filled by the vascular occlusion device 100, see Figures 21-24), and then advancing the delivery catheter 406 over the guidewire 408 to the target insertion site.

[0095] 21-25, an exemplary method 500 of deploying vascular occlusion device 100 in an anatomical body cavity using vascular occlusion system 200 will be described. Method 500 will be described in the context of deploying vascular occlusion device 100 in an aneurysmal sac 440, by way of example. However, method 500 is not limited to deploying vascular occlusion device 100 in an aneurysmal sac 440, but may be used to deploy vascular occlusion device 100, or another medical device disclosed herein, in any suitable anatomical body cavity accessible via a patient's vasculature. As shown in the flow chart of FIG. 25 and in FIG. 22, in step 502, guidewire 408 is inserted into patient's vasculature 442 and advanced to a target insertion site, i.e., aneurysmal sac 440. As described herein, the use of guidewire 408 is optional and not required in method 500 of deploying vascular occlusion device 100 using vascular occlusion system 200.

[0096] In step 504, the delivery catheter 406 of the delivery assembly 402 is advanced over the guidewire 408 to a position where the open distal end 418 is adjacent to or within the aneurysm neck 448 of the aneurysm 440, as shown in FIG. 23. In step 506, the guidewire 408 is withdrawn from the delivery catheter 406, leaving the delivery catheter 406 in place. In step 508, the vaso-occlusive assembly 404 is inserted into and advanced through the delivery catheter 406 of the delivery assembly 402 until the distal end of the vaso-occlusive device 100 is positioned adjacent the distal portion 418 of the delivery catheter 406, as shown in FIG. 23. In this position, the proximal portion 450 of the pusher member 410 remains proximal and outside the proximal portion 416 of the delivery catheter 406. Prior to insertion of vaso-occlusive device 100 into delivery catheter 406, vaso-occlusive device 100 may be pre-introduced into a sheath so that vaso-occlusive device 100 is in its constrained delivery configuration (primary configuration). Vascular occlusive device 100 is then inserted into delivery catheter 406 by abutting the distal end of the sheath with the proximal end 416 of delivery catheter 406 and pushing vaso-occlusive device 406 out of the sheath and into delivery catheter 406, such that vaso-occlusive device 100 remains in its delivery configuration within delivery catheter 206.

[0097] In step 510, the vaso-occlusive device 100 is pushed distally out of the delivery catheter 406 through the lumen 420 of the delivery catheter 406 by pushing the proximal portion 450 of the pusher member 412. In step 512, as the vaso-occlusive device 100 is pushed out of the open distal end 418 of the delivery catheter 406, the primary portion 104 is advanced through the aneurysm neck 448 and into the aneurysm sac 440, expanding the distal portion of the vaso-occlusive device 100 in the delivery configuration (primary configuration) to the secondary configuration (deployed configuration) and forming the primary loop 108 of the primary portion 104 within the aneurysm sac 440, as shown in FIG. 24. This causes the distal anchoring loop 105 to be deployed within the aneurysm sac 440 into a triangular shape in the secondary configuration. Also, in step 512, the primary loop 108 of the vaso-occlusive device 100 in the delivery configuration (primary configuration) is deployed to a secondary configuration (deployed configuration) forming the primary portion 104 by continuing to advance the vaso-occlusive device 100 out of the delivery catheter 406 via the pusher member 412. Finally, the base portion 106 is inserted into its secondary configuration within the aneurysm sac 440. Once the entire vaso-occlusive device 100 is inserted into the aneurysm sac 440, in step 514, the detachment device 412 is actuated, triggered or otherwise manipulated to detach the vaso-occlusive device 100 from the pusher member 410. In step 516, the pusher member 410 is removed from the patient's vasculature 442 by withdrawing it out through the delivery catheter 406. If a single vaso-occlusive device 100 is sufficient to fill and occlude the aneurysm sac 440, the method 500 proceeds to step 520, where the delivery catheter 406 is removed from the patient's vasculature 442. Alternatively, if multiple vaso-occlusive devices 100 are to be implanted, the process of steps 508-516 is repeated to deliver a sufficient number of vaso-occlusive devices 100 to fill and occlude the aneurysmal sac 440. Once a sufficient number of vaso-occlusive devices 100 have been implanted in the aneurysmal sac 440, in step 520, the delivery catheter 406 is removed.

[0098] While specific embodiments of the disclosed invention have been shown and described herein, those skilled in the art will understand that they are not intended to limit the invention. It will also be apparent to those skilled in the art that various changes and modifications (e.g., dimensions of various parts) can be made without departing from the scope of the disclosed invention, which is defined solely by the following claims and equivalents thereof. Accordingly, the specification and drawings should be regarded in an illustrative, rather than a restrictive, sense. The various embodiments of the disclosed invention shown and described herein are intended to cover alternatives, modifications and equivalents of the disclosed invention, which may fall within the scope of the appended claims.

Claims

1. 1. A vascular occlusion device comprising: a coil formed of wire having a primary configuration in a constrained state, the primary configuration having a proximal end and a distal end; The coil assumes a relaxed, unconstrained secondary configuration, the secondary configuration comprising: a primary portion including a plurality of primary loops, the primary portion including a distal primary loop being a most distal one of the primary loops, the distal primary loop having a proximal end and a distal end, the distal primary loop having a turn lying in a first plane and a plane substantially parallel to the first plane; a distal tether loop connected to a distal end of the distal primary loop, the distal tether loop having a substantially triangular shape, the size of the distal tether loop being smaller than the distal primary loop, and the distal tether loop being disposed within a projection of the distal primary loop.

2. 10. The vaso-occlusive device of claim 1, 1. A vascular occlusion device comprising: a pyramidal shaped portion formed from primary loops, each of the primary loops including a winding of wire that forms a closed loop of greater than 360 degrees; and the primary loops arranged in a pyramidal shape such that each primary loop is located on a different side of the pyramidal shape.

3. 3. The vaso-occlusive device of claim 2, A vascular occlusion device characterized in that each of the primary loops has a circumference that flares outward from the interior of the pyramidal shaped portion, and each of the primary loops is connected to one or more adjacent primary loops by transition segments of wire between each primary loop and one or more adjacent primary loops.

4. 3. The vaso-occlusive device of claim 2, The vaso-occlusive device, characterized in that the secondary configuration further comprises a body portion proximal to the pyramidal shaped portion, the body portion comprising a coil formed from wire and extending proximally from the pyramidal shaped portion.

5. 10. The vaso-occlusive device of claim 1, A vascular occlusion device, characterized in that the substantially triangular shape of the distal anchoring loop is formed from a base and two sides connected to the base, each of the two sides being connected to the base by a rounded apex, and the angle between the base and each of the two sides is between 15° and 75°.

6. 10. The vaso-occlusive device of claim 1, A vascular occlusion device, characterized in that the substantially triangular shape of the distal anchoring loop is formed from a base and two sides connected to the base, each of the two sides being connected to the base by a rounded apex, and the angle between the base and each of the two sides is between 25° and 50°.

7. 10. The vaso-occlusive device of claim 1, A vascular occlusion device characterized in that the distal primary loop has a circumference from a proximal end to a distal end, and the total length of the distal anchoring loop is 40% to 60% of the circumference of the distal primary loop.

8. 10. The vaso-occlusive device of claim 1, A vascular occlusion device characterized in that the start point of the distal anchoring loop where it connects to the distal primary loop is between the 10:00 position and the 11:00 position relative to the longitudinal axis of the primary configuration of the wire which is at the 12:00 position.

9. 10. The vaso-occlusive device of claim 1, A vascular occlusion device, characterized in that the distal anchoring loop is connected to the distal primary loop via a transition segment, and the start point of the distal anchoring loop is the location where the distal anchoring loop is connected to the transition segment.

10. 10. The vaso-occlusive device of claim 1, A vaso-occlusive device, wherein the distal anchoring loop lies out of the plane of the turns of the distal primary loop.

11. 10. The vaso-occlusive device of claim 1, A vascular occlusion device further comprising a second distal anchoring loop distal to the distal anchoring loop, the second distal anchoring loop having substantially the same shape and size as the distal anchoring loop and arranged parallel to the distal anchoring loop.

12. 4. The vascular occlusion device of claim 3, A vaso-occlusive device, characterized in that the pyramidal shape is a tetrahedron forming a triangular pyramid shape having three sides.

13. 4. The vaso-occlusive device of claim 3, A vaso-occlusive device, characterized in that the pyramidal shape is a pentahedron forming a quadrangular pyramid shape having four sides.

14. 4. The vascular occlusion device of claim 3, A vascular occlusion device, wherein the pyramidal shape is a polyhedron formed from a polygonal base having n sides and n side faces connected to a vertex.

15. 4. The vascular occlusion device of claim 3, A vaso-occlusive device wherein each of said primary loops comprises at least 1+1 / 3 turns.

16. 4. The vascular occlusion device of claim 3, A vaso-occlusive device, wherein the primary loops overlap at a transition from one primary loop to an adjacent primary loop.

17. The vascular occlusion device according to claim 1, A vaso-occlusive device, wherein the primary loops have different diameters.

18. The vascular occlusion device according to any one of claims 1 to 16, A vaso-occlusive device, wherein the primary loops have different numbers of turns.

19. The vascular occlusion device according to any one of claims 12 to 16, A vaso-occlusive device, wherein the primary configuration comprises an elongated helical coil.

20. The vascular occlusion device according to any one of claims 12 to 16, A vaso-occlusive device, wherein the wire is formed from a shape memory material and the secondary configuration is set by winding the wire around a mandrel and heat treating the wire wrapped around the mandrel.

21. The vascular occlusion device according to any one of claims 12 to 16, A vaso-occlusive device, wherein each of said primary loops has an average outer diameter that is 10-90% of the diameter of the aneurysm that said vaso-occlusive device is designed to treat.

22. The vascular occlusion device according to any one of claims 12 to 16, A vaso-occlusive device, wherein each of said primary loops has an average outer diameter that is 55-85% of the diameter of the aneurysm that said vaso-occlusive device is designed to treat.

23. 1. A method of manufacturing a vaso-occlusive device, comprising: Providing a mandrel, the mandrel comprising: A support member; a plurality of primary loop posts extending from the support member, each post spaced about the support member, the plurality of primary loop posts including a distal primary loop post having a first end connected to the support member and a second end extending away from the support member, the distal primary loop post having a first circumference for winding a wire onto the distal primary loop post; a distal anchoring loop sub-mandrel coupled to a second end of the distal primary loop post, the distal anchoring loop sub-mandrel configured to form a substantially triangular shaped loop from a wire wound on the distal anchoring loop sub-mandrel; providing a coil formed of wire having a primary configuration; winding a wire around each of the primary loop posts to form a primary portion of the vaso-occlusive device comprising a plurality of primary loops, the plurality of primary loops including a distal primary loop formed by winding a wire around the distal primary loop posts, the distal primary loop being a most distal of the primary loops and having a proximal end and a distal end, the distal primary loop having turns that lie in a first plane and a plane substantially parallel to the first plane; winding a wire around the distal tether loop sub-mandrel to form a distal tether loop connected to a distal end of the distal primary loop, the distal tether loop having a substantially triangular shape, the distal tether loop being smaller in size than the distal primary loop, and the distal tether loop being disposed within a projection of the distal primary loop; 23. A method comprising:

24. 24. The method of claim 23, The mandrel further comprises a body post extending from the support member, the method comprising: The method further comprises winding a wire around the body post to form a body portion of the vaso-occlusive device proximal to the primary portion, the body portion comprising a helical coil extending proximally from the primary portion.

25. 24. The method of claim 23, the primary portion includes a pyramidal shaped portion formed from the primary loops, each of the primary loops including a winding of wire that forms a closed loop greater than 360°, and the primary loops are arranged in a pyramidal shape such that each primary loop lies on a different side of the pyramidal shape.

26. 26. The method of claim 25, The pyramidal shape is a polyhedral shape formed from an n-sided polygonal base and n side surfaces leading to an apex.

27. 24. The method of claim 23, 11. The method of claim 10, wherein the support member is a central spherical element, the transition segments between adjacent primary loops are formed by traversing a wire along the spherical element, and each of the primary loops has a circumference that extends from the interior of the primary portion outwardly.

28. The method according to any one of claims 23 to 27, the substantially triangular shape of the distal anchoring loop is defined by a base and two sides connected to the base, each of the two sides being connected to the base by a rounded apex, and an angle between the base and each of the two sides is between 15° and 75°.

29. The method according to any one of claims 23 to 27, the substantially triangular shape of the distal anchoring loop is defined by a base and two sides connected to the base, each of the two sides being connected to the base by a rounded apex, and an angle between the base and each of the two sides is between 25° and 50°.

30. The method according to any one of claims 23 to 27, The method of claim 1, wherein the distal primary loop has a circumference from a proximal end to a distal end, and the total length of the distal anchoring loop is between 40% and 60% of the circumference of the distal primary loop.

31. The method according to any one of claims 23 to 27, the beginning of the distal anchoring loop where it joins the distal primary loop is between the 10:00 and 11:00 positions relative to the longitudinal axis of the primary configuration of wires which is at the 12:00 position.

32. The method according to any one of claims 23 to 27, The method of claim 1, wherein the distal tether loop is connected to the distal primary loop via a transition segment, and the beginning of the distal tether loop is the location where the distal tether loop is connected to the transition segment.

33. The method according to any one of claims 23 to 27, the distal anchoring loop being positioned out of plane of turns of the distal primary loop.

34. The method according to any one of claims 23 to 27, The method, wherein the primary configuration is a constrained configuration of wire and includes an elongated helical coil.

35. The method according to any one of claims 23 to 27, The wire is formed from a shape memory material, the method comprising: The method further comprising the step of heat treating the wire wrapped around the mandrel to set a secondary configuration of the vaso-occlusive device.

36. The method according to any one of claims 23 to 27, The method, wherein the secondary configuration is a relaxed, unconstrained configuration of the wire.

37. The method according to any one of claims 23 to 27, The method, wherein each of said primary loops has an average outer diameter that is 10-90% of the diameter of the aneurysm that said vasoocclusive device is designed to treat.

38. The method according to any one of claims 23 to 27, The method, wherein each of said primary loops has an average outer diameter that is 55-85% of the diameter of the aneurysm that said vasoocclusive device is designed to treat.

39. The method according to any one of claims 23 to 27, The method, wherein the primary loops have different diameters.

40. The method of claim 39, The method according to claim 1, wherein the primary loops have different numbers of turns.

Images