Embolization devices and methods thereof

Abstract

Embolization systems and associated methods include a delivery catheter, an embolization stylet, and an embolization medium, such as a hydrogel. In an embodiment, the embolization stylet defines a stylet lumen and comprises a proximal portion that extends linearly and an elastically deformable coiled distal portion that includes a plurality of apertures. The plurality of apertures communicate with the stylet lumen. Once the coil portion is deployed, the embolic medium is extruded from the plurality of apertures and transitions to a non-flowable state to form a plug. In an embodiment, the stylet includes a brush portion having a plurality of bristles and is deployed to an expanded configuration. The embolization medium flows over the brush in the expanded configuration to form a plug. Once cured, the brush can either be removed from the embolization medium or left in place to provide additional mechanical support.

Description

EMBOLIZATION DEVICES AND METHODS THEREOFBACKGROUND

[0001] Current embolization techniques for treating vascular disorders involve the deliberate occlusion of blood vessels, often to manage conditions such as aneurysms, arteriovenous malformations, or control bleeding. One aspect of these procedures is the development of efficient and versatile embolization systems that can adapt to diverse anatomical scenarios.

[0002] Embolic agents, ranging from metallic coils to liquid embolic materials, have been pivotal in vascular occlusion procedures. However, the conventional approaches may face challenges in achieving a comprehensive and enduring closure of the target vessel. Scaffoldbased systems offer enhanced mechanical support, anchoring within the vessel, but often lack the ability to provide an effective seal, leaving room for potential complications. Conversely, hydrogel-based embolic agents offer improved sealing capabilities but may lack the necessary structural support for stable, long-term vessel occlusion.

[0003] What is needed therefore is an integrated embolization system that combines the mechanical stability provided by a scaffold with the sealing properties of a hydrogel plug. Embodiments described herein are directed to address the foregoing problems by providing an embolization system that combines mechanical stability and efficient sealing to enhance the safety and efficacy of vascular occlusion procedures.SUMMARY

[0004] In some aspects, the techniques described herein relate to an embolization system including, a delivery catheter defining a catheter lumen, an embolization stylet disposed within the catheter lumen and defining a stylet lumen, the embolization stylet including, a proximal portion extending linearly, and a distal portion defining a coiled configuration having a plurality of coils and transitionable to a linear configuration, the distal portion further including a plurality of apertures communicating with the stylet lumen, and an embolic medium transitionable from a flowable state to a non-flowable state to form a plug, the embolic medium in the flowable state flowing through the stylet lumen, through the plurality of apertures, and transitioning to the non-flowable state about an outer surface of the distal portion to form the Plug.

[0005] In some aspects, the techniques described herein relate to an embolization system, wherein the embolic medium is a hydrogel transitionable from a relatively fluid, flowable state, to a relatively solid state to form the plug.

[0006] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion is elastically deformable to the linear configuration.

[0007] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion is detachable from the proximal portion.

[0008] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion is releasably coupled with the proximal portion by way of a threaded, snap-fit, latch, press-fit, or interference fit engagement.

[0009] In some aspects, the techniques described herein relate to an embolization system, wherein one or both of the proximal portion and the distal portion formed of a shape memory material.

[0010] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion is triggered to transition between the coiled configuration and the linear configuration in response to a change in temperature.

[0011] In some aspects, the techniques described herein relate to a method of embolizing a blood vessel including, advancing a delivery catheter and a stylet assembly to a target location, the stylet disposed within a lumen of the delivery catheter, advancing a distal portion of the stylet distally of a distal end of the delivery catheter, transitioning the distal portion of the stylet from a linear configuration to a non-linear configuration having a plurality of coils, flowing an embolization medium through a lumen of the stylet and through a plurality of apertures disposed in a wall of the distal portion, and curing the embolization medium from a flowable state to a non-flowable state to form a plug, the embolization medium disposed about an outer surface of the distal portion in the non-linear configuration.

[0012] In some aspects, the techniques described herein relate to a method, wherein the embolization medium is a hydrogel.

[0013] In some aspects, the techniques described herein relate to a method, further including withdrawing the stylet relative to the delivery catheter to withdraw the distal portionfrom the embolization medium and into the catheter lumen prior to withdrawing the delivery catheter and the stylet assembly from a vasculature.

[0014] In some aspects, the techniques described herein relate to a method, further including detaching the distal portion from a proximal portion of the stylet and withdrawing the delivery catheter and the proximal portion leaving the distal portion disposed within the plug of embolization medium.

[0015] In some aspects, the techniques described herein relate to a method, wherein detaching the distal portion from the proximal portion further includes rotating the proximal portion to threadably disengage the proximal portion from the distal portion.

[0016] In some aspects, the techniques described herein relate to an embolization system including, a delivery catheter defining a catheter lumen, an embolization stylet disposed within the catheter lumen including, a proximal portion extending linearly, and a distal portion having a stem extending axially and a plurality of bristles extending perpendicular to the stem and transitionable between a folded configuration and an expanded configuration, and an embolic medium transitionable from a flowable state to a non-flowable state to form a plug, the embolic medium flowable through the delivery catheter lumen and through the plurality of bristles to transition to the non-flowable state and form the plug about the distal portion.

[0017] In some aspects, the techniques described herein relate to an embolization system, wherein the embolic medium is a hydrogel transitionable from a relatively fluid, flowable state, to a relatively solid state to form the plug.

[0018] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion in the folded configuration includes the plurality of bristles folded distally to define a relatively smaller lateral cross-sectional area relative to the expanded configuration where the plurality of bristles define a relatively larger lateral cross-sectional area.

[0019] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion is detachable from the proximal portion.

[0020] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion is releasably coupled with the proximal portion by way of a threaded, snap-fit, latch, press-fit, or interference fit engagement.

[0021] In some aspects, the techniques described herein relate to an embolization system, wherein one or both of the proximal portion and the distal portion formed of a shape memory material.

[0022] In some aspects, the techniques described herein relate to an embolization system, wherein the distal portion formed of the shape memory material is configured to transition between the folded configuration and the expanded configuration in response to a change in temperature.BRIEF DESCRIPTION OF DRAWINGS

[0023] A more particular description of the present disclosure will be rendered by reference to specific embodiments thereof that are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. Example embodiments of the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

[0024] FIG. 1 shows a distal section of a coil embolization system in a linear configuration disposed within a vasculature, in accordance with embodiments disclosed herein.

[0025] FIG. 2 shows a distal section of a coil embolization system in a deployed configuration within a vasculature, in accordance with embodiments disclosed herein.

[0026] FIG. 3 shows a distal section of a coil embolization system in a retracted configuration with an embolization plug placed within the vasculature, in accordance with embodiments disclosed herein.

[0027] FIG. 4 shows a distal section of a coil embolization system in a detached configuration with an embolization plug and coil within the vasculature and detached from a proximal portion of a stylet and delivery catheter assembly of the embolization system, in accordance with embodiments disclosed herein.

[0028] FIG. 5 shows a distal section of a brush embolization system in a retracted configuration disposed within a vasculature, in accordance with embodiments disclosed herein.

[0029] FIG. 6 shows a distal section of a bush embolization system in a deployed configuration within a vasculature, in accordance with embodiments disclosed herein.

[0030] FIG. 7 shows a distal section of a coil embolization system in a deployed configuration with an embolization medium being extruded from the delivery catheter, in accordance with embodiments disclosed herein.

[0031] FIG. 8 shows a distal section of a brush embolization system in a deployed configuration with an embolization plug placed within the vasculature, in accordance with embodiments disclosed herein.

[0032] FIG. 9 shows a distal section of a coil embolization system in a detached configuration with an embolization plug and brush portion within the vasculature and detached from a proximal portion of a stylet and delivery catheter assembly of the embolization system, in accordance with embodiments disclosed herein.DESCRIPTION

[0033] Before some particular embodiments are disclosed in greater detail, it should be understood that the particular embodiments disclosed herein do not limit the scope of the concepts provided herein. It should also be understood that a particular embodiment disclosed herein can have features that can be readily separated from the particular embodiment and optionally combined with or substituted for features of any of a number of other embodiments disclosed herein. It is understood that the drawings are diagrammatic and schematic representations of exemplary embodiments of the invention and are neither limiting nor necessarily drawn to scale.

[0034] Regarding terms used herein, it should also be understood the terms are for the purpose of describing some particular embodiments, and the terms do not limit the scope of the concepts provided herein. Ordinal numbers (e.g., first, second, third, etc.) are generally used to distinguish or identify different features or steps in a group of features or steps, and do not supply a serial or numerical limitation. For example, “first,” “second,” and “third” features or steps need not necessarily appear in that order, and the particular embodiments including such features or steps need not necessarily be limited to the three features or steps. Labels such as“left,” “right,” “top,” “bottom,” “front,” “back,” and the like are used for convenience and are not intended to imply, for example, any particular fixed location, orientation, or direction. Instead, such labels are used to reflect, for example, relative location, orientation, or directions. Singular forms of “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. Also, the words “including,” “has,” and “having,” as used herein, including the claims, shall have the same meaning as the word “comprising.”

[0035] In the following description, the terms “or” and “and / or” as used herein are to be interpreted as inclusive or meaning any one or any combination. As an example, “A, B or C” or “A, B and / or C” mean “any of the following, A, B, C, A and B, A and C, B and C, A, B and C.” An exception to this definition will occur only when a combination of elements, components, functions, steps or acts are in some way inherently mutually exclusive.

[0036] With respect to “proximal,” a “proximal portion” or a “proximal end portion” of, for example, a catheter disclosed herein includes a portion of the catheter intended to be near a clinician when the catheter is used on a patient. Likewise, a “proximal length” of, for example, the catheter includes a length of the catheter intended to be near the clinician when the catheter is used on the patient. A “proximal end” of, for example, the catheter includes an end of the catheter intended to be near the clinician when the catheter is used on the patient. The proximal portion, the proximal end portion, or the proximal length of the catheter can include the proximal end of the catheter; however, the proximal portion, the proximal end portion, or the proximal length of the catheter need not include the proximal end of the catheter. That is, unless context suggests otherwise, the proximal portion, the proximal end portion, or the proximal length of the catheter is not a terminal portion or terminal length of the catheter.

[0037] With respect to “distal,” a “distal portion” or a “distal end portion” of, for example, a catheter disclosed herein includes a portion of the catheter intended to be near or in a patient when the catheter is used on the patient. Likewise, a “distal length” of, for example, the catheter includes a length of the catheter intended to be near or in the patient when the catheter is used on the patient. A “distal end” of, for example, the catheter includes an end of the catheter intended to be near or in the patient when the catheter is used on the patient. The distal portion, the distal end portion, or the distal length of the catheter can include the distal end of the catheter; however, the distal portion, the distal end portion, or the distal length of the catheter need not include the distal end of the catheter. That is, unless context suggestsotherwise, the distal portion, the distal end portion, or the distal length of the catheter is not a terminal portion or terminal length of the catheter.

[0038] To assist in the description of embodiments described herein, as shown in FIG. 1, a longitudinal axis extends substantially parallel to an axial length of the catheter. A lateral axis extends normal to the longitudinal axis, and a transverse axis extends normal to both the longitudinal and lateral axes.

[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art.

[0040] FIGS. 1-4 show an embodiment of a coil embolization system (“coil system”) 100 generally including a delivery catheter (“catheter”) 110 and an embolization stylet (“stylet”) 130. The delivery catheter 110 defines a catheter lumen 112 and extends between a proximal end and a distal tip 114, the distal tip 114 including an aperture 118 communicating with the catheter lumen 112. The catheter 110 is configured to extend through a vasculature, e.g., vessel 90 defining a vessel lumen 92, to a target location that is to be embolized.

[0041] The embolization stylet 130 is disposed within the catheter lumen 112 and defines a stylet lumen 132 extending between a proximal end and a distal tip 134 of the stylet 130. In an embodiment, the stylet distal tip 134 includes an aperture 138 that communicates with the stylet lumen 132. The stylet 130 can be formed of a plastic, polymer, metal, alloy, composite, shape-memory material, super-elastic material, a nickel titanium alloy, Nitinol, or the like. The stylet 130 includes a proximal portion 140 and a distal portion 150. In an embodiment, the proximal portion 140 and a distal portion 150 of the stylet 130 are formed integrally as a single monolithic piece. In an embodiment, the proximal portion 140 and a distal portion 150 of the stylet 130 are releasably coupled to each other, for example using a threaded 158, snap-fit, latch, press-fit, interference fit engagement, or similar coupling mechanism.

[0042] In an embodiment, the proximal portion 140 of the stylet 130 extends linearly along a longitudinal axis. The proximal portion 140 is flexible and has relatively strong columnar strength. This allows for elastic deformation perpendicular to the longitudinal axis but resists buckling or kinking when an axial force is applied thereto. As such the proximal portion 140 provides a pushrod to urge the stylet 130 and catheter 110 assembly through tortuous vascular pathways, or to urge the stylet 130 axially through the catheter lumen 112.In an embodiment, the proximal portion 140 provides a pushrod to urge the stylet axially relative to the catheter 110.

[0043] In an embodiment, as shown in FIG. 2, a distal portion 150, or “coil” portion 150, of the stylet 130 defines a non-linear shape having a plurality of curves orbends extending in a variety of angles and directions relative to the longitudinal axis of the stylet 130. As shown in FIG. 1, the coil portion 150 can be elastically deformable to a linear configuration when disposed within the catheter lumen 112. As shown in FIG. 2, when the coil portion 150 is urged distally of the catheter distal tip 114, the coil portion 150 can resume the coiled resting state, i.e., an elastically undeformed, non-linear shape.

[0044] In an embodiment, the plurality of coils and bends formed by the coil portion 150 defines an embolization plug that is configured to fill a cavity or portion of a vessel lumen 92. In an embodiment, as shown in FIG. 2, the coil portion 150 twists and coils to form a bundle that expands radially outward from the longitudinal axis of the proximal portion 140 and impinges on an inner wall of the vessel 92 to retain the coil 150 at a target location within the vessel 90. In an embodiment, the coil portion 150 embolizes the target location of the vessel 90 to reduce a blood flow therethrough. In an embodiment, the coil portion 150 embolizes the target location of the vessel 90 to prevent any blood flow therethrough.

[0045] In an embodiment, the one or more of the distal portion 150, the proximal portion 140, or the stylet 130 as a whole, is formed of a shape memory material configured to modify the mechanical properties thereof in response to a trigger, such as a change in temperature, between the inside of the patient’s body or vasculature, and the outside of the patient’s body or vasculature, or between the inside of the catheter lumen 112 and the outside of the catheter lumen 112, or combinations thereof. The differences in mechanical properties can either provide greater rigidity and increased columnar strength, or can provide greater flexibility to negotiate tortuous vascular pathways. In an embodiment, the coil portion 150 includes a shape memory material configured to transition between a linear configuration and a non-linear, or coiled, configuration, as described herein, in response to the trigger.

[0046] In an embodiment, the trigger can be a change in temperature, moisture, pH, salinity, or the like. For example, when the coil portion 150 is disposed within the catheter lumen 112 the coil portion 150 can define a linear shape extending along a longitudinal axis. When the coil portion 150 is extended beyond the distal tip 114 of the catheter 110 and exposedto the environment within the vessel lumen 92, the coil 150 undergoes a phase change and defines the non-linear, coiled configuration, as described herein. In an embodiment, the coil portion 150 can be configured to undergo a similar phase change to transition between a linear and non-linear shape, in response to the presence or absence of an embolizing medium, as described in more detail herein.

[0047] In an embodiment, the embolization system 100 further includes an embolization medium 160 configured to transition between a flowable state and a non-fl owable state. In a flowable state, the embolization medium is configured to flow from a proximal end of the embolization system 100, through stylet lumen 132 to the stylet distal aperture 138. In an embodiment, the coil portion 150 further includes a plurality of apertures 152 extending through a side wall of the coil portion 150 and communicating with the stylet lumen 132. In an embodiment, the embolization medium 160 is extruded through the distal aperture 138, the plurality of apertures 152, or combinations thereof.

[0048] In an embodiment, the embolization medium 160 is a hydrogel configured to transition from a flowable state to a non-flowable state. In an embodiment, the embolization medium 160 can reversibly transition between the flowable state and the non-flowable state. In an embodiment, the embolization medium 160 irreversibly transitions from the flowable state to the non-flowable state. In an embodiment, the embolization medium 160 transitions in response to a trigger, such as a temperature, time, or chemical (e.g., pH, salinity, etc.) -based trigger. For example, a hydrogel embolization medium 160 defines a flowable state within the stylet lumen 132 and transitions to a non-flowable state when exposed to the environment within the vessel lumen 92. In an embodiment, the embolization medium 160 in the non- flowable state is configured to form an embolization plug to mitigate or prevent fluid flow through a target location within the vessel lumen 92.

[0049] In an exemplary method of use, as shown in FIG. 1, the stylet 130 and catheter 110 assembly is advanced through the vasculature to a target location to be embolized. As shown in FIG. 2, once at the target location, the stylet 130 is advanced distally relative to the catheter 110 so that the coil portion 150 extends distally of the catheter distal tip 114. As the coil portion 150 extends from the catheter lumen 112, the coil portion 150 transitions to the non-linear, coiled configuration. The plurality of coils and bends of the coil portion 150 arrange in either a regular or irregular pattern to form an embolization bundle that expands radially to fill the vessel lumen 92. In an embodiment, the outer perimeter of the embolizationbundle impinges on an inner wall of the vessel lumen 92 to secure the coil portion 150 at the target location within the vessel 90. In an embodiment, the coil portion 150 is secured in place at the target location by stabilizing the proximal portion 140 of the stylet 130.

[0050] With continued reference to FIG. 2, once the coil portion 150 is deployed, the flowable embolization medium 160 is urged through stylet lumen 132 and extruded through one or both of the distal aperture 138 and the plurality of apertures 152 disposed in a wall portion of the coil 150. In an embodiment, the embolization medium 160 is a hydrogel, however other types of flowable embolization media are also contemplated to fall within the scope of the present invention. Once extruded from the stylet lumen 132, the embolization medium 160 is configured to transition from a flowable state to a non-fl owable state. Various triggers for transitioning the state of the embolization medium 160 are contemplated including temperature, fluids, pH, or the like, as described herein. For example, the embolization medium 160 can be a hydrogel that transitions from a flowable state to a relatively non- flowable, or solid, state on contact with the blood within the vessel 90, to form an embolization plug. Advantageously, the coil portion 150 in the deployed, non-linear shape, provides a scaffold to support the embolization medium 160 as the embolization medium 160 transitions from the flowable state to the non-flowable and form the embolization plug.

[0051] In an embodiment, as shown in FIG. 3, once the embolization medium 160 has at least partially cured, or fully set to the non-flowable state, the stylet 130 can be withdrawn proximally to withdraw the coil portion back into catheter lumen 112. As the coil portion 150 is withdrawn into the catheter lumen 112, the coil portion 150 can elastically deform, or transition, back to the linear configuration. The catheter 110 and stylet 130 assembly can then be withdrawn from the vasculature 90 leaving the embolization plug in place.

[0052] In an embodiment, as shown in FIG. 4, the coil portion 150 can be detachable from the proximal portion 140 of the stylet 130, as described herein. For example, the coil portion 150 is threadably engaged 158 with the proximal portion 140. As such, once the embolization medium 160 has at least partially cured, the proximal portion 140 can be rotated to detach the coil portion 150 from the proximal portion 140. The coil portion 150 can be left in place, at the target location and in the deployed configuration. Advantageously, the coil 150 provides additional mechanical support to the embolization plug formed by the embolization medium 160. The catheter 110 and the proximal portion 140 of the stylet 130 can then be withdrawn leaving the coil 150 and the embolization medium 160 in place.

[0053] FIGS. 5-9 show an embodiment of a brush embolization system (“brush system”) 200. The brush system 200 generally includes a delivery catheter 110 and an embolization stylet 230 configured to be disposed within the catheter 110. The delivery catheter 110 includes a lumen 112 extending from a proximal end to a distal tip 114. The catheter distal tip 114 including a distal aperture 118 communicating with the catheter lumen 112.

[0054] The embolization stylet 230 includes a proximal portion 240 and a distal portion 250. In an embodiment, the proximal portion 240 and a distal portion 250 of the stylet 230 are formed integrally. In an embodiment, the proximal portion 240 and the distal portion 250 of the stylet 230 are releasably coupled to each other, for example using a threaded 258, snap-fit, latch, press-fit, interference fit engagement, or similar coupling mechanism. In an embodiment, the proximal portion 240 of the stylet 230 extends linearly along a longitudinal axis, as described herein. As such, the proximal portion 240 provides a pushrod to urge the stylet 230 and catheter 110 assembly through tortuous vascular pathways, or to urge the stylet 230 axially through the catheter lumen 112.

[0055] In an embodiment, the distal “brush” portion 250 includes a stem 252 extending axially and a plurality of bristles 254 extending perpendicular to the stem 252. The plurality of bristles 254 are disposed radially about the stem 252 in either in a regular or irregularly dispersed pattern. The plurality of bristles 254 are elastically deformable from the perpendicular position to a folded position extending distally. As shown in FIG. 5, when the brush portion 250 is disposed within the catheter lumen 112, the catheter 110 elastically deforms the brush portion 250 to a folded position. In an embodiment, the folded position includes the plurality of bristle 254 folded in a distal direction to define a relatively smaller lateral cross-sectional area relative to an expanded position where the plurality of bristle 254 are folded in a distal direction to define a relatively larger lateral cross-sectional area.

[0056] As shown in FIG. 6, when the catheter 110 and stylet 230 are at the target location, the catheter 110 can be withdrawn proximally relative to the stylet 230, and / or the stylet 230 can be advanced distally relative to the catheter 110. With the brush portion 250 disposed outside of the catheter 110 the bristles 254 expand to a relatively undeformed, or expanded configuration. To note the bristles 254 in the expanded configuration may still be deflected from the perpendicular position to impinge on an inner wall of the vessel 90.

[0057] In an embodiment, one or more of the plurality of bristles 254, the stem 252, the distal portion 250, the proximal portion 240, and the stylet 230, or combinations thereof, can be formed of a plastic, polymer, metal, plastic, polymer, metal, alloy, composite, shapememory material, super-elastic material, a nickel titanium alloy, Nitinol, or the like. In an embodiment, the distal portion 250 can be formed of a shape memory material configured to transition between a folded position and an expanded position in response to a trigger, as described herein.

[0058] In an exemplary method of use, a brush embolization system 200 is provided as described herein. As shown in FIG. 5, the brush stylet 230 is disposed within the catheter lumen 112 which elastically deforms the bristles 254 of the brush 250 to a folded position. The catheter 110 and brush stylet 230 assembly is then advanced through a vasculature to a target location within a vessel 90.

[0059] As shown in FIG. 6, once at the target location, the delivery catheter 110 can be withdrawn relative to the stylet 230 so that the brush portion 250 is distal of the catheter distal tip 114. The bristles 254 transition to the expanded configuration and impinge on a vessel wall 90. The bristles 254 in the expanded configuration can be deflected in a distal direction, or a downstream direction so that the ends of the plurality of bristles 254 impinge on the vessel wall and secure the brush portion 250 in place at the target location.

[0060] As shown in FIG. 7, an embolization medium 160, as described herein, is extruded through the catheter lumen 112 over the stylet 230 and over the bristles 254. Advantageously, the bristles 254 provide a scaffold to support the embolization medium 160 while the embolization medium 160 transitions to a non-fl owable state and form an embolization plug. Further, the embolization medium 160 flowing over the plurality of bristles 254 creates a “capillary action” to draw the embolization medium 160 radially outwards and fill the shape of the bristles 254 which have expanded, in the expanded configuration, to match the cross-sectional shape of the vessel 90 at the target location.

[0061] As shown in FIG. 8, in an embodiment, with the embolization medium 160 at least partially transitioned to the non-flowable state, the brush 250 is withdrawn proximally out of the embolization medium and back into the catheter lumen 112. As the brush portion 250 is withdrawn into the catheter lumen 112, brush 250 transitions back to the foldedconfiguration. The stylet 230 and catheter 110 assembly is then withdrawn proximally from the target location leaving the plug of embolization medium 160 in place.

[0062] In an embodiment, as shown in FIG. 9, the brush portion 250 is detachable from the proximal portion 240 of the stylet 230. For example, the stem 252 of the brush portion 250 is threadably engageable 258 with the distal end of the proximal portion 240. For example, once the embolization medium 160 has been extruded from the catheter lumen 112, the proximal portion 240 can be rotated to detach the brush portion 250 and leave the brush portion 250 in place within the embolization medium 160. Advantageously, the brush portion 250 provides a scaffold to provide mechanical support to the plug of embolization medium 160. Advantageously, the ends of the bristles 254 impinging on the inner wall of the vessel 90 further secures the embolization plug 160 in place at the target location. The proximal portion 240 and the catheter 110 assembly can then be withdrawn proximally.

[0063] Advantageously, embodiments described herein integrate the mechanical advantages of a scaffold plug with the improved sealing properties of a hydrogel plug. The embolization system offers a versatile solution adaptable to various vascular anatomies. The combination of a mechanical scaffold for structural reinforcement and a hydrogel plug for sealing creates a comprehensive and tailored approach to embolization procedures, contributing to improved patient care and outcomes.

[0064] While some particular embodiments have been disclosed herein, and while the particular embodiments have been disclosed in some detail, it is not the intention for the particular embodiments to limit the scope of the concepts provided herein. Additional adaptations and / or modifications can appear to those of ordinary skill in the art, and, in broader aspects, these adaptations and / or modifications are encompassed as well. Accordingly, departures may be made from the particular embodiments disclosed herein without departing from the scope of the concepts provided herein.

Claims

CLAIMSWhat is claimed is:

1. An embolization system, comprising: a delivery catheter defining a catheter lumen; an embolization stylet disposed within the catheter lumen and defining a stylet lumen, the embolization stylet comprising: a proximal portion extending linearly; and a distal portion defining a coiled configuration having a plurality of coils and transitionable to a linear configuration, the distal portion further including a plurality of apertures communicating with the stylet lumen; and an embolic medium transitionable from a flowable state to a non-fl owable state to form a plug, the embolic medium in the flowable state flowing through the stylet lumen, through the plurality of apertures, and transitioning to the non-flowable state about an outer surface of the distal portion to form the Plug.

2. The embolization system according to claim 1, wherein the embolic medium is a hydrogel transitionable from a relatively fluid, flowable state, to a relatively solid state to form the plug.

3. The embolization system according to claim 1, wherein the distal portion is elastically deformable to the linear configuration.

4. The embolization system according to claim 1, wherein the distal portion is detachable from the proximal portion.

5. The embolization system according to claim 4, wherein the distal portion is releasably coupled with the proximal portion by way of a threaded, snap-fit, latch, press-fit, or interference fit engagement.

6. The embolization system according to claim 1, wherein one or both of the proximal portion and the distal portion formed of a shape memory material.

7. The embolization system according to claim 6, wherein the distal portion is triggered to transition between the coiled configuration and the linear configuration in response to a change in temperature.

8. A method of embolizing a blood vessel, comprising: advancing a delivery catheter and a stylet assembly to a target location, the stylet disposed within a lumen of the delivery catheter; advancing a distal portion of the stylet distally of a distal end of the delivery catheter; transitioning the distal portion of the stylet from a linear configuration to a nonlinear configuration having a plurality of coils; flowing an embolization medium through a lumen of the stylet and through a plurality of apertures disposed in a wall of the distal portion; and curing the embolization medium from a flowable state to a non-flowable state to form a plug, the embolization medium disposed about an outer surface of the distal portion in the non-linear configuration.

9. The method according to claim 8, wherein the embolization medium is a hydrogel.

10. The method according to claim 8, further including withdrawing the stylet relative to the delivery catheter to withdraw the distal portion from the embolization medium and into the catheter lumen prior to withdrawing the delivery catheter and the stylet assembly from a vasculature.

11. The method according to claim 8, further including detaching the distal portion from a proximal portion of the stylet and withdrawing the delivery catheter and the proximal portion leaving the distal portion disposed within the plug of embolization medium.

12. The method according to claim 11, wherein detaching the distal portion from the proximal portion further includes rotating the proximal portion to threadably disengage the proximal portion from the distal portion.

13. An embolization system, comprising: a delivery catheter defining a catheter lumen; an embolization stylet disposed within the catheter lumen, comprising:a proximal portion extending linearly; and a distal portion having a stem extending axially and a plurality of bristles extending perpendicular to the stem and transitionable between a folded configuration and an expanded configuration; and an embolic medium transitionable from a flowable state to a non-fl owable state to form a plug, the embolic medium flowable through the delivery catheter lumen and through the plurality of bristles to transition to the non-fl owable state and form the plug about the distal portion.

14. The embolization system according to claim 13, wherein the embolic medium is a hydrogel transitionable from a relatively fluid, flowable state, to a relatively solid state to form the plug.

15. The embolization system according to claim 13, wherein the distal portion in the folded configuration includes the plurality of bristles folded distally to define a relatively smaller lateral cross-sectional area relative to the expanded configuration where the plurality of bristles define a relatively larger lateral cross-sectional area.

16. The embolization system according to claim 13, wherein the distal portion is detachable from the proximal portion.

17. The embolization system according to claim 16, wherein the distal portion is releasably coupled with the proximal portion by way of a threaded, snap-fit, latch, press-fit, or interference fit engagement.

18. The embolization system according to claim 13, wherein one or both of the proximal portion and the distal portion formed of a shape memory material.

19. The embolization system according to claim 18, wherein the distal portion formed of the shape memory material is configured to transition between the folded configuration and the expanded configuration in response to a change in temperature.

20. A method of embolizing a blood vessel, comprising: advancing a delivery catheter and stylet assembly to a target location, the stylet disposed within a lumen of the delivery catheter and including a distalportion having a plurality of bristles extending perpendicular to a longitudinal axis; withdrawing the delivery catheter proximally relative to the stylet; transitioning the plurality of bristles from a folded configuration to an expanded configuration; flowing an embolization medium through a lumen of the delivery catheter and through the plurality of bristles; and curing the embolization medium to a non-flowable state, the embolization medium disposed about the plurality of bristles.

21. The method according to claim 20, wherein the embolization medium is a hydrogel.

22. The method according to claim 21, further including withdrawing the stylet relative to the delivery catheter to withdraw the distal portion from the embolization medium and into the catheter lumen prior to withdrawing the delivery catheter and stylet assembly from a vasculature.

23. The method according to claim 21 , further including detaching the distal portion from the proximal portion and withdrawing the delivery catheter and the proximal portion assembly leaving the distal portion disposed within a plug of embolization medium.

24. The method according to claim 23, wherein detaching the distal portion from the proximal portion further includes rotating the proximal portion to threadably disengage the proximal portion from the distal portion.

25. The method according to claim 21, wherein plurality of bristles of the distal portion are formed of a shape-memory material and transitioning the plurality of bristles from the folded configuration to the expanded configuration includes triggering a phase change in the shape memory material by a change in temperature.

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