Stent System

Abstract

A stent assembly for implantation into a blood vessel includes an inlet zone having at least one inlet stent structure, the inlet stent structure having an inlet radial force configured to self-expand and at least substantially conform to a non-circular cross-sectional shape of the blood vessel. The stent assembly also includes a patent zone having at least one patent stent structure positioned distal to the inlet stent structure, the patent stent structure being self-expanding and having a patent radial force greater than the inlet radial force, the patent stent structure being configured to be positioned upstream from a stenosis along the blood vessel and coupled to the inlet stent structure such that the patent stent structure is configured to be positioned at the stenosis in the blood vessel.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 445,771, filed February 15, 2023, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to devices and methods for treating diseases associated with narrowing of a blood vessel lumen. The devices and methods may be directed to positioning a stent assembly in a dural venous sinus to restore and / or maintain a desired patency of the sinus. [Background technology]

[0003] Stenosis of the intracranial dural venous sinuses is now recognized as an anatomical condition associated with several diseases. For example, stenosis of the intracranial dural venous sinuses can cause idiopathic intracranial hypertension (IIH), pulsatile tinnitus (PT), chronic migraine, headache, cognitive decline, and, in some cases, blindness. Such stenosis has traditionally been treated, rather unsuccessfully, with weight loss, high-dose carbonic anhydrase inhibitors, cerebrospinal fluid (CSF) shunt procedures, and optic nerve sheath fenestration (ONSF) surgery. In addition to having limited long-term effectiveness, these treatments also have various associated risks and difficulties.

[0004] Recently, conventional stents (e.g., arterial stents) designed to treat lesions or other blockages in blood vessels have been implanted in dural venous sinuses to treat stenosis. These conventional stents are designed to reopen and maintain patency of blood vessels with plaque, intimal hyperplasia, calcification, or thrombus that impair blood flow. These conventional stents are designed with sufficient radial force and coverage to expand against these severe lesions, not only to reopen the vessel and restore patency, but also to protect against restenosis. Conventional stents are also designed to avoid compression of the stented portion of the vessel to avoid occluding the vessel. Furthermore, conventional stents also have a circular cross-sectional shape, and many conventional stents are generally relatively short.

[0005] In fact, conventional stents are not well-suited for treating dural venous stenosis. For example, the region of the dural venous sinus immediately upstream of an implanted conventional stent collapses in 12% to 25% of cases, necessitating the implantation of an additional upstream stent to reopen the collapsed section (known as a "revision"). Conventional stents and their delivery to the target location also cause intracranial hemorrhage in a substantial percentage of cases. Furthermore, dural venous sinus stenosis often requires several conventional stents to cover the narrowed and adjacent portions of the vessel. This requires a highly skilled practitioner who can precisely operate a complex system of nested catheters to reach the target location and deploy multiple stents. As a result, conventional stents have several drawbacks for treating dural cerebral venous sinus stenosis. Summary of the Invention [Means for solving the problem]

[0006] The accompanying drawings, which are not necessarily to scale, form part of the specification and disclose various principles and advantages of the systems, apparatus, and methods of the present technology. Like numerals may refer to the same or similar features having similar structure and functionality throughout the different drawings. Advantages of embodiments of the systems, apparatus, and methods will become apparent from the following detailed description. The drawings and related description are provided to illustrate some, but not all, embodiments or examples of the present technology and are not intended to limit the scope of the claimed invention in any way. [Brief explanation of the drawings]

[0007] [Figure 1A] 1 is a schematic illustration of a portion of a venous sinus and jugular canal with an embodiment of a stent positioned within a portion of a delivery catheter. [Figure 1B] FIG. 1 is a cross-sectional view of a normal, non-constricted portion of the transverse sinus. [Figure 1C] 1C is a cross-sectional view of a stenotic portion of the transverse sinus taken along line 1C-1C of FIG. 1A. [Figure 1D] 1D is a cross-sectional view of a stenotic portion of the transverse sinus along line 1D-1D in FIG. 1A, with arachnoid granulations. [Figure 2A] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 2A-1] 2B is a schematic cross-sectional view of several embodiments of zones along the stent assembly of FIG. 2A in accordance with the present technology. [Figure 2A-2] 2B is a schematic cross-sectional view of several embodiments of zones along the stent assembly of FIG. 2A in accordance with the present technology. [Figure 2B] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 2B-1] 2C is a schematic cross-sectional view of several embodiments of zones along the stent assembly of FIG. 2B in accordance with the present technology. [Figure 2C] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 2D]1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 2E] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 2E-1] 2B is a schematic cross-sectional view of several embodiments of zones along the stent assembly of FIG. 2A in accordance with the present technology. [Figure 2F] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 2G] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 2G-1] 2B is a schematic cross-sectional view of several embodiments of zones along the stent assembly of FIG. 2A in accordance with the present technology. [Figure 3] 1A-1C are side views that schematically illustrate some embodiments of stent assemblies with transition zones in accordance with the present technology. [Figure 3-1] 4A-4C are schematic cross-sectional views of several embodiments of zones along the stent assembly of FIG. 3 in accordance with the present technology. [Figure 4] 1A-1C are side views that schematically illustrate some embodiments of stent assemblies with transient pressure zones in accordance with the present technology. [Figure 4-1] 5A-5C are schematic cross-sectional views of several embodiments of zones along the stent assembly of FIG. 4 in accordance with the present technology. [Figure 5A] 10A-10C are schematic cross-sectional views of several embodiments of zones of a stent assembly with bend regions in accordance with the present technology; [Figure 5B] 10A-10C are schematic cross-sectional views of several embodiments of zones of a stent assembly with bend regions in accordance with the present technology; [Figure 6] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 7A] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 7B] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 7C] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 8A] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 8B] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 9A] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 9B] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 9C] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 9D] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 10] 1A-1D are schematic side views of some embodiments of stent assemblies according to the present technology. [Figure 11A] 1A-1C are schematic diagrams of cross-sectional shapes of portions of selected stent structures of some embodiments of stent assemblies according to the present technology. [Figure 11B] 1A-1C are schematic diagrams of cross-sectional shapes of portions of selected stent structures of some embodiments of stent assemblies according to the present technology. [Figure 11C] 1A-1C are schematic diagrams of cross-sectional shapes of portions of selected stent structures of some embodiments of stent assemblies according to the present technology. DETAILED DESCRIPTION OF THE INVENTION

[0008] overview The systems, devices, and methods of the present technology are related to treating diseases associated with narrowing of the vascular lumen, such as impaired blood flow caused by collapsed / constricted blood vessel walls and / or occlusions. Some embodiments are directed to positioning a stent assembly in a dural venous sinus to maintain a desired patency of the sinus. However, the disclosed embodiments are merely examples of various embodiments of the present technology, and thus, the disclosed embodiments may be used in other types of blood vessels, such as cardiac, pulmonary, and / or peripheral blood vessels. As such, the specific structural and functional details disclosed herein are not intended to be limiting, but merely as a basis for the claims and as a representative basis for teaching those skilled in the art to perform and use the systems, devices, and methods with appropriately detailed structures. Furthermore, the terms and phrases used herein are not intended to be limiting, but rather to provide an understandable description of the systems, devices, and methods.

[0009] FIG. 1A illustrates a portion of the dural venous sinus system, including the internal jugular vein 100, the sigmoid sinus 110, the transverse sinus 120, and the superior sagittal sinus 130. Blood flows from the superior sagittal sinus 130 toward the internal jugular vein 100. Dural venous stenosis often occurs when the transverse sinus 120 has a narrowed section 150 in which the vessel wall constricts, impairing the vessel lumen and blood flow. This often results in an upstream location 160 between the narrowed section 150 and the superior sagittal sinus 130. Additionally, arachnoid granulations 125, which are arachnoid pockets that allow cerebrospinal fluid (CSF) to enter the dural venous sinuses through the venous system, can form throughout the dural venous sinuses, causing intrinsic narrowing or a reduction in the cross-sectional area of ​​the vessels. This can impair blood flow through the dural venous sinuses and increase pressure within the vessels.

[0010] FIG. 1B is a cross-sectional view of a normal portion of the transverse sinus 120 without a stenotic portion, and FIG. 1C is a cross-sectional view of a stenotic portion 150 of the transverse sinus 120 along line 1C-1C in FIG. 1A. Referring to FIG. 1B, a normal transverse sinus 120 has a three-sided cross-sectional shape between the bone 170 and the brain 172, with cerebrospinal fluid 174 residing in the space between the transverse sinus 120 and the brain 172. As used herein, such a three-sided shape is generally described as triangular because the sides may curve inward and / or outward. Referring to FIG. 1C, dural venous stenosis often occurs when cerebrospinal fluid pressure increases to a degree that overcomes the blood pressure in the transverse sinus and the structural integrity of the vessel wall (arrow P). FIG. 1D depicts a stenotic portion 150 due to arachnoid granulations in the sigmoid sinus 110. Accordingly, some embodiments of the present technology are directed to deploying a stent assembly over a guidewire 210 via a delivery catheter 200 along the sigmoid sinus 110, along the transverse sinus 120, and optionally into the superior sagittal sinus 130 to restore patency to a narrowed portion 150 of the dural venous sinus.

[0011] This technology addresses the shortcomings of implanting conventional stents into dural venous sinuses. Unlike plaque, thrombus, intimal hyperplasia, and calcification, which occlude or clog blood vessels, dural venous sinus stenosis primarily occurs when an increase in extravascular cerebrospinal fluid pressure overcomes intravascular pressure and the inherent crush resistance of the sinus wall. Therefore, instead of requiring sufficient radial force to push plaque, calcification, or other obstructions radially outward to restore patency, the radial force required to open the dural venous sinus only needs to overcome these extravascular forces. In some cases, dural venous sinus stenosis can also be caused by arachnoid granulations within the sinus; again, these obstructions require only a small radial force to restore patency. Additionally, the transverse sinus 120 and superior sagittal sinus 130 generally have a triangular cross-sectional shape, and conventional arterial and venous stents generally expand to have a circular cross-sectional shape when deployed in the blood vessel. As a result, the inventors first recognized that these differences between dural sinus stenosis and other types of stenosis in other blood vessels are part of the reason why conventional stents have some drawbacks when treating dural sinus stenosis.

[0012] For example, the region of the dural sinus immediately upstream of an implanted conventional stent collapses in 12% to 25% of cases, as previously described. The inventors believe that the large radial forces exerted by conventional stents on the transverse sinus vessel wall and the circular cross-sectional shape of conventional stents result in a region of low pressure at the upstream end of the stent, which further collapses a portion of the transverse sinus wall immediately upstream of the stent, restricting flow. Furthermore, the circular cross-sectional shape and large radial forces of conventional stents may contribute to intracranial hemorrhage and other undesirable effects, such as large forces on the vessel wall (dura, periosteum) causing pain or distortion of the vessel wall. Furthermore, conventional stents generally do not have the necessary length or adequate cross-sectional area to stent the entire target region, which can be approximately 12 cm or more (e.g., 12 cm to 20 cm, or 14 cm to 18 cm) when stenting from the superior sagittal sinus to the sigmoid sinus. As a result, several conventional stents are typically required to cover the narrowed portion of the blood vessel, which requires a highly skilled practitioner to operate a complex system of nested catheters to precisely deploy multiple stents.

[0013] Another attribute of the transverse sinuses 120 is that, under normal physiological conditions, portions of the vessel respond almost immediately to elevated CSF pressure (e.g., coughing, Valsalva maneuvers, snoring, etc.) by developing a localized stenosis in the lateral transverse sinus, allowing a transient pressurization of the dural sinuses proximally that dissipates as the CSF pressure dissipates. The transient development of localized stenosis in both lateral transverse sinuses allows pressure to build up in the upstream dural sinuses, thereby allowing the rest of the system (now pressurized) to resist collapse due to a CSF pressure spike. The large radial force of a conventional stent does not compress in response to such a change in CSF pressure, which limits how much pressure can develop in the proximal sinuses, thereby hindering the sinuses' ability to resist collapse during a CSF pressure spike.

[0014] The present technology is directed to a stent assembly and method for treating a stenosed portion of a blood vessel that addresses these shortcomings of conventional stents. In some embodiments, a stent assembly for implantation into a blood vessel comprises at least an inlet zone and a patent zone. The inlet zone has at least one inlet stent structure having an inlet radial force configured to self-expand and at least substantially conform to the non-circular cross-sectional shape of the blood vessel. The patent zone has at least one patent stent structure positioned distal to the inlet stent structure. The patent stent structure is self-expanding and has a patent radial force greater than the inlet radial force, and the patent stent structure is coupled to the inlet stent structure such that the inlet stent structure is configured to be positioned upstream from the stenosis along the blood vessel and the patent stent structure is configured to be positioned at the stenosis in the blood vessel.

[0015] In some embodiments, a stent assembly for implantation into a blood vessel comprises at least an inlet zone and a patent zone. The inlet zone has at least one inlet stent structure configured to self-expand and at least substantially conform to a non-circular cross-sectional shape of the blood vessel. The patent zone has at least one patent stent structure positioned distal to the inlet stent structure. The patent stent structure is configured to self-expand and expand to an expanded shape that is different from the non-circular cross-sectional shape of the blood vessel, whereby the blood vessel at least substantially conforms to the patent stent structure. The patent stent structure is coupled to the inlet stent structure such that the inlet stent structure is configured to be positioned upstream from a stenosis along the blood vessel and the patent stent structure is configured to be positioned at the stenosis of the blood vessel.

[0016] In some embodiments, a stent assembly for implantation into a blood vessel comprises an inlet zone and a patent zone. The inlet zone comprises at least one inlet stent structure that is self-expanding and has an inlet radial force that compresses with increasing external pressure on the blood vessel. The patent zone comprises at least one patent stent structure that is self-expanding and has a patent radial force that is greater than the inlet radial force. The patent radial force is sufficient to maintain patency of the blood vessel as external pressure on the blood vessel increases.

[0017] The present technology is directed to methods for treating symptoms caused by stenosis along a dural venous sinus. Some embodiments of methods according to the present technology include positioning a stent assembly in a dural venous sinus so that (a) an ostium zone of the stent assembly is located upstream from the stenosed portion of the dural venous sinus relative to blood flow through the dural venous sinus, and (b) a patent zone of the stent assembly is located in the stenosed portion of the dural venous sinus. The method further includes expanding the ostium stent structure in the ostium zone and expanding the patent zone in the dural venous sinus. The ostium stent structure is expanded at the upstream location to have a triangular cross-sectional shape that at least substantially approximates the generally triangular cross-sectional shape of the dural venous sinus at the upstream location, and the ostium stent structure has an ostium radial force. The patent stent structure is expanded at the stenotic portion of the dural venous sinus to increase the cross-sectional area of ​​the stenotic portion, and the patent stent structure has a patent radial force that is greater than the ostium radial force.

[0018] In some embodiments, a method according to the present technology includes positioning a stent assembly in a dural venous sinus such that (a) an ostium zone of the stent assembly is at a location upstream from a stenosed portion of the dural venous sinus with respect to blood flow through the dural venous sinus, and (b) a patent zone of the stent assembly is at the stenosed portion of the dural venous sinus. The method further includes (a) expanding the ostium stent structure of the ostium zone so that the ostium stent structure at the ostium zone at least substantially conforms to the non-circular cross-sectional shape of the upstream location of the dural venous sinus, and (b) expanding the patent zone patent structure to an expanded shape such that the non-circular cross-sectional shape of the stenosed portion of the dural venous sinus at least substantially conforms to the expanded shape of the patent stent structure. The patent stent structure is expanded in the stenosed portion of the dural venous sinus to increase the cross-sectional area of ​​the stenosed portion of the dural venous sinus.

[0019] In some embodiments, the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend into a generally triangular shape when expanded into contact with the vessel, and the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend into a generally triangular shape when expanded into contact with the vessel. In some embodiments, the inlet structure has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to at least substantially approximate the triangular shape of the upstream location, and the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to expand into a generally circular cross-sectional shape when expanded into contact with the vessel. In some embodiments, the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend into a generally triangular cross-sectional shape when expanded into contact with the vessel.

[0020] In some embodiments, the inlet radial force of the inlet stent structure is from about 0.0005 N / mm to about 2 N / mm and the patent radial force of the patent stent structure is from about 0.001 N / mm to about 3 N / mm, hi some embodiments, the patent radial force of the patent stent structure is configured to limit constriction of the blood vessel when external pressure on the blood vessel increases.

[0021] In some embodiments, the stent assembly further comprises an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force. In some embodiments, the stent assembly further comprises a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure. In some embodiments, the stent assembly further comprises a transient pressure zone adjacent the patent zone and having a transitional stent structure with a transient radial force configured to contract during a structural physiological spike in cerebrospinal fluid pressure.

[0022] In some embodiments, the inlet structure comprises an inlet annulus with struts, and the patent stent structure comprises a patent annulus with struts. In some embodiments, the inlet annulus is a cut or etched hypotube with inlet struts, and the patent stent structure is a cut or etched hypotube with patent struts having a larger cross-sectional area than the inlet struts. In some embodiments, the inlet structure comprises a braided mesh, and the patent stent structure comprises a patent annulus with struts. In some embodiments, the inlet stent structure comprises an inlet braided mesh section having an inlet radial force, and the patent stent structure comprises a patent braided mesh section having a patent radial force. The inlet braided mesh section can be a different braided mesh from the patent braided mesh section, or the inlet braided mesh section and the patent braided mesh section can be part of a single, integrated braided mesh, with the braid angle, number of wires, wire thickness, and / or other parameters differing between the inlet braided mesh section and the patent braided mesh section.

[0023] In some embodiments, a stent assembly for implantation into a blood vessel comprises at least an inlet zone and a patent zone. The inlet zone has at least one inlet stent structure having an inlet radial force configured to self-expand and at least substantially conform to the non-circular cross-sectional shape of the blood vessel. The patent zone has at least one patent stent structure positioned distal to the inlet stent structure (e.g., downstream from the inlet stent structure relative to the direction of blood flow). The patent stent structure self-expands and has a patent radial force greater than the inlet radial force, and the patent stent structure is coupled to the inlet stent structure such that the inlet stent structure is configured to be positioned upstream from the stenosis along the blood vessel and the patent stent structure is configured to be positioned at the stenosis in the blood vessel. The stent assembly may further comprise one or more additional patent zones, and / or one or more exit zones, transition zones, intermediate transition zones, and / or transient pressure zones. The exit zone can include at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force. A transition zone can be between the inlet and patent zones, with the transition stent structure having a transition radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure. An intermediate transition zone can be positioned within the patent zone or between the patent zones. A transient pressure zone can be within the patent zone, between the patent zone and the exit zone, or between the patent zone and any transition zone, intermediate transition zone, or inlet zone. The transient pressure zone can have a transition stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure. In some embodiments, the transitional stent structure can be connected to a distal portion of the inlet stent structure and a proximal portion of the patent stent structure, and the transitional stent structure can be connected to a distal portion of the patent stent structure and a proximal portion of the outlet stent structure.

[0024] In some embodiments, the patency zone has a similar radial force as the inlet zone, but the inlet zone is constructed to conform to the shape of the vessel better than the patency zone. This can be accomplished by having the inlet zone with more struts radially around the stent structure and / or by having a stent structure that is longer longitudinally.

[0025] Some aspects of the present technology are also directed to methods of treating symptoms caused by stenosis along a dural venous sinus. In some embodiments, the method includes positioning a stent assembly in a dural venous sinus such that (a) an ostium zone of the stent assembly is located upstream from a stenosed portion of the dural venous sinus relative to blood flow through the dural venous sinus, and (b) a patent zone of the stent assembly is located in the stenosed portion of the dural venous sinus. The method can include expanding an ostium stent structure in the ostium zone at the upstream location to have a three-sided cross-sectional shape (e.g., at least a generally triangular shape) that at least substantially approximates the generally triangular cross-sectional shape of the dural venous sinus, the ostium stent structure having an ostium radial force. The method can further include expanding a patent stent structure in the patent zone at the stenosed portion of the dural venous sinus such that the patent stent structure increases the cross-sectional area of ​​the stenosed portion of the dural venous sinus, the patent stent structure having a patent radial force greater than the ostium radial force.

[0026] In some embodiments of the method, the entry stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the entry stent structure includes allowing the entry stent structure to self-expand so that the entry stent structure at least substantially approximates the generally triangular cross-sectional shape of the upstream location.

[0027] In some embodiments of the method, the ostial stent structure is coupled to the patent stent structure before positioning the stent assembly in the dural venous sinus so that a single stent assembly is positioned upstream of the dural venous sinus and along the narrowed portion.

[0028] In some embodiments, the symptom is papilledema. In some embodiments, the symptom is pulsatile tinnitus. In some embodiments, the symptom is headache or chronic migraine.

[0029] In some embodiments of the method, the ostium stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the ostium stent structure comprises self-expanding the ostium stent structure such that it at least substantially approximates a generally triangular cross-sectional shape of an upstream location, and the patent stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the patent stent structure comprises self-expanding the patent stent structure such that it at least substantially approximates a generally triangular cross-sectional shape of a stenosed portion of a dural venous sinus. In some embodiments of the method, upon expansion, the generally triangular cross-sectional shape of the ostium stent structure differs from the generally triangular cross-sectional shape of the patent stent structure.

[0030] In some embodiments of the method, the inlet stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the inlet stent structure includes self-expanding the inlet stent structure so that the inlet stent structure at least substantially approximates the generally triangular cross-sectional shape of the upstream location, and the patent stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the patent stent structure includes self-expanding the patent stent structure so that it expands into the generally circular cross-sectional shape when it contacts and expands with the blood vessel.

[0031] In some embodiments of the method, positioning the stent assembly in the dural venous sinus further includes positioning an exit zone of the stent assembly at a location downstream from the narrowed portion of the dural venous sinus, relative to blood flow through the dural venous sinus, the exit zone having an exit stent structure with an exit radial expansion force that is less than the patency expansion force. In some embodiments of the method, the exit stent structure of the exit zone is expanded at the downstream location such that the exit stent structure has a cross-sectional shape that approximates the cross-sectional shape at the downstream location.

[0032] Although some embodiments are directed to positioning in the dural venous sinuses, aspects of the present technology may be applied to using one or more stents for implantation in other blood vessels in the body of a human or animal subject. Some embodiments, as noted above, are directed to implanting one or more stents to restore blood flow in the venous sinuses, specifically the transverse sinus 120, the sigmoid sinus 110, and / or the superior sagittal sinus 130.

[0033] Still further in accordance with the present technology, one or more stent structures may include an inlet zone. The inlet zone is constructed to allow a smooth transition from the native vessel to the stent and the stented portion of the vessel. The inlet zone may conform, at least in part, to the general shape of the native vessel. The inlet zone may conform to the native vessel without substantially overstretching the vessel to reduce disruption of blood flow from the native vessel to the stented region.

[0034] Still further in accordance with the present technology, one or more stent structures may include one or more transition zones that provide a transition from the inlet zone to the patent zone of the stent with increased radial force compared to the inlet zone, which also provides reduced turbulence within the stent.

[0035] Still further in accordance with the present technology, one or more stent structures may include one or more intermediate transition zones that provide a transition within or between one or more patent zones, and can have a reduced radial force compared to one or more adjacent patent zones.

[0036] Still further in accordance with the present technology, the one or more stent structures include one or more patency zones (e.g., body zones) that provide a desired level of radial force to restore and maintain vascular patency in a stenosed or target region, and optionally, in adjacent or more distant regions of the vessel.

[0037] Still further in accordance with the present technology, one or more stents may comprise one or more transient pressure zones. The transient pressure zones flex (e.g., reduce cross-sectional area) in response to physiological changes when external pressure on the vessel wall increases, causing the vessel's cross-sectional area to decrease, thereby forcing the vessel wall to move radially outward when the external pressure decreases. This allows the vessel to have a natural response to transient increases in cerebrospinal fluid pressure. For example, when there is a transient spike in cerebrospinal fluid pressure, at least a portion of the stented vessel can become smaller in cross-sectional area, and when the pressure decreases, that portion of the stented vessel can recover (e.g., increase in cross-sectional area).

[0038] Still further in accordance with the present technology, one or more stent assemblies may include an exit zone or zones that serve to reduce flow disturbances as blood exits the stented region.

[0039] Still further in accordance with the present technology, one or more stent assemblies may include a bending region to allow at least a portion of the stent to more easily conform to the vessel wall without delivering undesirable, more than necessary, or excessive pressure to the vessel wall.

[0040] Still further, in accordance with the present technology, one or more stent assemblies may be constructed with a rounded cross-sectional profile (e.g., as a circle) and / or may be constructed with a rounded cross-sectional profile (e.g., as a circle) when deployed in free space and in a vessel in which at least a portion of the stent conforms to the general shape of the native vessel.

[0041] Still further in accordance with the present technology, one or more stent assemblies may be constructed in the form of the relative shape of the vessel into which the stent will be deployed when unconstrained in free space, or in the form of the relative shape of the vessel into which the stent will bend to approximate the relative shape of the vessel into which it will be deployed.

[0042] Still further in accordance with the present technology, one or more stent assemblies may be constructed such that at least a portion of the stent can be deployed into a blood vessel and, if desired, recaptured back into the delivery catheter.

[0043] Still further in accordance with the present technology, one or more stent assemblies may be constructed to have greater radial force when partially constrained to resist further compression and facilitate better sinus decompression than when nominally fully expanded.

[0044] Still further in accordance with the present technology, one or more stent assemblies can be constructed from a shape memory material, such as NiTi or a NiTi alloy, to enable self-expansion in the blood vessel when deployed from a delivery catheter.

[0045] Detailed Description of Selected Embodiments of the Technology 2A-2I are side views schematically illustrating some embodiments of a stent assembly 300 in accordance with the present technology. Referring to FIG. 2A, the stent assembly 300 can include one or more zones, and in some embodiments, the stent assembly 300 includes at least two zones having different expansion characteristics. In some embodiments, the stent assembly 300 includes an inlet zone 310 and a patent zone 370 (e.g., a main body zone). As shown in FIG. 2A, the inlet zone 310 includes at least one inlet stent structure 312 configured to self-expand and bend to at least substantially approximate a non-circular cross-sectional shape of a portion of the blood vessel at the inlet zone 310. The inlet stent structure 312 can have an inlet radial force. The patent zone 370 includes at least one patent stent structure 372 configured to self-expand and expand to an expanded shape that increases the cross-sectional area of ​​another portion of the blood vessel at the patent zone 370. For example, other portions of the blood vessel in the patent zone 370 can expand and at least substantially conform to the expanded shape of the patent stent structure 372. The patent stent structure 372 can have a patent radial force that is greater than the inlet radial force. The stent structure 312 / 372 can be rings comprising struts 303 and / or braided mesh. For example, the rings can be cut or etched from hypotube, and the braided mesh can be a wire or polymer braid.

[0046] In some embodiments, the patent stent structure 372 is directly coupled to the inlet stent structure 312 by a flexible link 305 such that the inlet stent structure 312 is positioned upstream from the narrowed portion of the blood vessel, and the patent stent structure is positioned in the narrowed portion of the blood vessel. In some embodiments, such as some described below, the patent stent structure 372 is indirectly coupled to the inlet stent structure 312, with other zones having other stent structures between the patent stent structure 372 and the inlet stent structure 312 (see, for example, FIG. 2B ). In either case, the inlet stent structure 312 and the patent stent structure 372 are “coupled” to each other. In some embodiments, the patent stent structure 372 is directly coupled to the inlet stent structure 312 without a link 305, via welding, adhesives, fasteners (e.g., sutures, fibers), or other suitable techniques.

[0047] 2A-1 is a cross-sectional view of some embodiments of an inlet stent structure 312 and a patent stent structure 372 when deployed. In some embodiments, the inlet stent structure 312 has at least a generally circular cross-sectional shape (not shown) in an unconstrained expanded state and is configured to bend into a generally triangular shape 314 (shown) when expanded into contact with an upstream location in the blood vessel, and the patent stent structure 372 has at least a generally circular cross-sectional shape (not shown) in an unconstrained expanded state and is configured to bend into a different triangular shape 374 when expanded into contact with a stenosed portion of the blood vessel. In some embodiments, the inlet stent structure 312 has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to have a generally triangular shape 314 that at least substantially approximates the generally triangular shape of the upstream location. In some embodiments, as shown in FIG. 2A-2 , the patent stent structure 372 is configured to have at least a generally circular cross-sectional shape (not shown) in an unconstrained, expanded state and to expand to a generally circular cross-sectional shape (not shown) when expanded into contact with a stenosed portion of a blood vessel. As shown in FIG. 2A-2 , when expanded, the inlet stent structure 312 has a generally triangular cross-sectional shape 314 and the patent stent structure 372 has at least a generally circular cross-sectional shape 374. The inlet stent structure 312 can flex accordingly to accommodate the generally triangular cross-sectional shape of the portion of the blood vessel in the inlet zone 310, while the patent stent structure 372 at least substantially maintains its generally circular cross-sectional shape such that the portion of the blood vessel having a non-circular cross-sectional shape in the patent zone 370 at least substantially conforms to the generally circular cross-sectional shape of the expanded patent stent structure 372.

[0048] The inlet radial force of the inlet stent structure 312 is selected so that the inlet stent band 310 at least substantially conforms to the natural shape of the upstream location. When the stent assembly 300 is implanted in a dural venous sinus such that the inlet band 310 is at the transverse sinus 120, the inlet band 310 is expected to have a generally triangular shape that at least substantially approximates the triangular cross-sectional shape of the corresponding portion of the transverse sinus 120. This feature is expected to reduce the low-pressure region at the inlet of the stent assembly 300 because the inlet band 310 does not substantially overexpand and deform relative to the upstream vessel. As a result, the stent assembly 300 is expected to reduce or prevent vessel collapse upstream from the stent assembly, which should reduce the rate of "revision" procedures.

[0049] The patent radial force of patent stent structure 372 is selected so that patent zone 370 restores patency to the stenosed portion of the blood vessel. The patent radial force can be selected, for example, to be greater than the pressure of cerebrospinal fluid to cause the stenosed portion of the blood vessel to expand outward and restore patency. As a result, the cross-sectional shape of the expanded patent stent structure 372 reshapes the stenosed portion of the blood vessel to restore blood flow therethrough.

[0050] In some embodiments, the inlet radial force of the inlet stent structure 312 is from approximately 0.0005 N / mm to approximately 2 N / mm, and the patent radial force of the patent stent structure 372 is from approximately 0.001 N / mm to approximately 3 N / mm. In some embodiments, the patent radial force of the patent stent structure 372 is configured to limit constriction of the blood vessel when external pressure on the blood vessel increases.

[0051] 2B is a side cross-sectional view of some embodiments of a stent assembly 300. In this embodiment, the stent assembly comprises an inlet zone 310, an optional first transition zone 330, an optional second transition zone 350, a first patent zone 370 (e.g., a first body zone), a second patent zone 390 (e.g., a second body zone), and an outlet zone 410. Each zone can have one or more stent structures. For example, the entrance zone 310 can comprise an entrance stent structure 312, the first transition zone 330 can comprise a first transition stent structure 332, the second transition zone 350 can comprise a second transition stent structure 352, the first patent zone 370 can comprise a first patent stent structure 372, the second patent zone 390 can comprise a second patent stent structure 392, and the exit zone 410 can comprise an exit stent structure 412.

[0052] The number of zones and the number of stent structures in each zone can vary depending on the application. Each stent structure can comprise at least one ring with struts 303 and / or at least one braided wire mesh. In some embodiments, the stent structures in at least some zones of stent assembly 300 can have a round cross-sectional shape when unconstrained in free space (i.e., in an unconstrained, fully expanded state), and when deployed in the vasculature, at least some of the stent structures of stent assembly 300 can bend to at least generally approximate the relative shape of a corresponding portion of a native blood vessel. In some embodiments, some stent structures in one or more of the zones can have an unconstrained, expanded cross-sectional shape that is different from the cross-sectional shape of a corresponding portion of a blood vessel at the target site, such that upon expansion, the corresponding portion of the blood vessel at least substantially conforms to the unconstrained cross-sectional shape of such stent structure. In some embodiments, the stent structures of at least some bands of the stent assembly 300 can have the relative shape of a corresponding portion of a blood vessel in an unconstrained, fully expanded state and when deployed in the vasculature. In some embodiments, the stent structures of at least some bands of the stent assembly 300 can have the relative shape of a corresponding portion of a blood vessel in an unconstrained, fully expanded state and can bend to more closely approximate the relative shape of the corresponding portion of a blood vessel when deployed in the vasculature. The stent assembly 300 may also include interconnecting links 305 connecting adjacent stent structures together. Alternatively, adjacent stent structures may be directly connected to each other without the use of links 305. The number of links 305 connecting the stent structures can vary along the length of the stent assembly 300. The links 305 can be arranged linearly, in a helical pattern, or in any combination along the longitudinal length of the stent assembly 300.

[0053] The stent structures in different zones can have different cross-sectional profiles and physical properties along the length of the stent assembly 300. For example, in the embodiment shown in Figures 2B and 2B-1, the stent structures 312, 332, 352, 372, 392 can progress from a stent structure of relatively lower radial force (e.g., the entry stent structure 312) to a stent structure of relatively higher radial force (e.g., the second patent stent structure 392). As a result, in some embodiments, the cross-sectional shapes of the deployed stent structures can vary along the length of the stent assembly depending on the radial force of the stent structures and the cross-sectional shapes of the corresponding regions of the vessel into which the stent assembly 300 is deployed. 2B-1 , upon deployment in the sigmoid sinus 110 ( FIG. 1 ), the second patent stent structure 392 can have an almost or generally circular cross-sectional shape 394 that at least substantially approximates the shape of the sigmoid sinus 110, or a rounded square cross-sectional shape 414. Upon deployment in the transverse sinus 120 ( FIG. 1 ), the ostium stent structure 312 can have a generally triangular shape 314 that at least substantially approximates the triangular shape of the transverse sinus 120.

[0054] Some embodiments of the stent assembly 300 can manage blood flow into and through the stent assembly 300 to reduce (e.g., minimize or eliminate) flow disturbances or turbulence. To achieve this result, different zones of the stent assembly 300 can be generally shaped like corresponding regions of the blood vessel into which the stent assembly 300 is implanted and / or can curve upon expansion to at least substantially approximate the native cross-sectional shape of a corresponding portion of a healthy native blood vessel. The general cross-sectional shape can extend throughout the length of the stent assembly 300 or over only a specific length of the stent assembly 300 such that flow disturbances are reduced or eliminated. The reduction / elimination of flow disturbances is typically expected to reduce the "correction" of collapse of the native blood vessel adjacent to the inflow side of the stent assembly 300. For example, in some embodiments, entrance zone 310, optional first transition zone 330, optional second transition zone 350, and exit zone 410 are configured to curve so that they at least substantially approximate corresponding regions located along sigmoid sinus 110 and transverse sinus 120 and / or in superior sagittal sinus 130. In contrast, first patent zone 370 and second patent zone 390 are configured to at least substantially have the shape of first patent zone 370 and second patent zone 390 in an unconstrained expanded state and to reshape the stenosed portion of the blood vessel to restore blood flow therethrough.

[0055] In some embodiments, the inlet zone 310 can be a shape-memory material formed from cut or etched hypotube or braided fibers to have either a generally triangular or a generally circular cross-sectional shape in an unconstrained, expanded state, and is sufficiently elastic to conform to the cross-sectional shape of the vessel when expanded within the vessel such that the shape of the corresponding portion of the native vessel is at least substantially unchanged (e.g., so that the inlet zone 310 at least substantially approximates the cross-sectional shape of the portion of the vessel into which it is implanted). The inlet zone 310 can have an outward radial force of approximately 0.0005 N / mm to approximately 2 N / mm, or approximately 0.05 N / mm to approximately 0.5 N / mm. The inlet zone 310 can be comprised of one or more stent structures and can extend over a length of approximately 1 mm to approximately 100 mm, or approximately 5 mm to approximately 25 mm. The inlet zone 310 can be directly connected to the patent zone 370, or the inlet zone 310 and patent zone 370 can be indirectly connected to one another with one or more other zones having an intermediate radial force stent structure and a link 305 between the inlet zone 310 and one of the patent zones 370. In some embodiments, the radial force of the zones can increase continuously from the inlet zone 310 through the second patent zone 390 along a continuous ramp and / or multiple steps.

[0056] 2B , the first transition zone 330 and the second transition zone 350 can provide a gradual increase in radial force between the inlet zone 310 and the first patent zone 370. For example, the first patent zone 370 can have a radial force of approximately 0.001 N / mm to approximately 3 N / mm, and at least a portion of the first transition zone 330 can have a radial force of approximately 0.001 N / mm to approximately 1.5 N / mm. Also, at least a portion of the second transition zone 350 can have a radial force of approximately 0.002 N / mm to approximately 2.5 N / mm. This allows at least a portion of the first transition zone 330 to have a radial force greater than the inlet zone 310 and less than at least a portion of the second transition zone 350. Similarly, at least a portion of second transition zone 350 can have a radial force that is less than at least a portion of first patency zone 370. Referring to FIG. 2B-1 , the deployed contours of first transition zone 330 and second transition zone 350 within a vessel are shown as first transition zone contour 334 and second transition zone contour 354, respectively. The entire transition zone can extend over a length from approximately 2 mm to approximately 50 mm or more.

[0057] In some embodiments, one or more of the entrance zone 310, transition zones 330 / 350, patent zones 370 / 390, and exit zone 410 have variable radial forces so that the stent assembly 300 does not collapse to a diameter of less than 3 mm, even in supraphysiological conditions. For example, if the radial force at full expansion is between approximately 0.05 N / mm and approximately 1.5 N / mm, when the stent assembly 300 is compressed to a diameter of 3 mm (or a circumference of 9 mm) or less, the radial force will be approximately 2 N / mm or greater. This allows for sufficient sinus decompression despite changes in cerebrospinal fluid pressure, without undue strain on the native dural sinuses, at maximum expansion.

[0058] In certain embodiments, the patent zones 370 / 390 of the stent assembly 300 have sufficient radial force to hold a vessel open under the highest expected external pressures as well as internal requirements, such as to maintain sufficient blood flow through the vessel. The patent zones 370 / 390 of the stent assembly 300 can have a stent structure (e.g., zones) with a consistent radial force or stiffness. Also, one or more zones can have different radial forces (i.e., multiple patent regions), or one or more zones can have continuously varying radial forces and / or constant or varying cross-sectional areas. In this manner, the entire length of the stent assembly 300 can effectively have varying degrees of radial force, providing a constant radial force and / or varying radial force along the length.

[0059] 2B, the radial force exerted by the patency zones 370 / 390 is typically from approximately 0.001 N / mm to approximately 3 N / mm, or from approximately 0.04 N / mm to approximately 2 N / mm. For example, the first patency zone 370 can have a radial force necessary to restore patency along at least a portion of the superior sagittal sinus 130 and / or the transverse sinus 120 (FIG. 1), and the second patency zone 390 can have a different radial force to restore patency along at least a portion of the transverse sinus 120 and / or the sigmoid sinus 110. For example, the first patency radial force of the first patency zone 370 can be from approximately 0.001 N / mm to approximately 2.5 N / mm, and the second radial force of the second patency zone 390 can be from approximately 0.005 N / mm to approximately 3 N / mm. The lengths of the patency zones, individually or combined, can be from approximately 50 mm to approximately 200 mm for placements extending from at or near the torcula to the sigmoid sinus 110, including placement in the superior sagittal sinus 130.

[0060] 2C is a side view that schematically illustrates some embodiments of a stent assembly 300 in which the cross-sectional area of ​​at least some of the stent structures increases from the inlet zone 310 to the outlet zone 410. For example, the inlet stent structure 312 in the inlet zone 310 can have an inlet cross-sectional dimension (e.g., from the center point to the struts 303 or wires of the strut structure), and the second patent zone 390 can have a second patent cross-sectional dimension that is larger than the inlet cross-sectional dimension. The cross-sectional dimension of the transition zones 330 / 350 can be larger than the cross-sectional dimension of the inlet zone 310 but smaller than the cross-sectional dimension of the second patent zone 390, and the cross-sectional dimension of the first patent zone 370 can be smaller than the cross-sectional dimension of the second patent zone 390. In some embodiments, the cross-sectional dimension of each zone can increase continuously from the inlet zone 310 to the second patent zone 390. In some embodiments, each stent structure within each zone can have the same cross-sectional dimension, or in the case of zones with multiple stent structures, the cross-sectional dimension of each stent structure within the zone can increase continuously toward the exit zone 410. One aspect of increasing the cross-sectional dimension toward the exit zone 410 is to change the properties of the stent structure. Increasing the cross-sectional dimension can not only increase radial force, but can also be used to increase the amount of stent structure surface area in contact with the vessel wall. This can be useful when arachnoid granulations are present. Arachnoid granulations typically occur on the lateral sides of the transverse sinuses 120 and may also occur in the proximal sigmoid sinus 110, so having a larger stent structure surface area against the vessel wall per unit area in these regions can reduce local stress concentrations. The medial transverse sinus 120 or superior sagittal sinus 130 are less prone to arachnoid granulations, so the surface area can be smaller. The configuration of the stent structure may be used to adjust the amount of surface area of ​​the stent structure relative to the vessel wall, for example, by increasing the amount of material in the stent structure to reduce stress concentrations.

[0061] 2D is a side view that schematically illustrates some embodiments of the stent assembly 300 having a reduced diameter in the exit zone 410 compared to one or more patent zones. The reduced diameter of the exit zone 410 can reduce disruption or turbulence of blood flow exiting the stent assembly 300 and into the native vessel. Additionally, reducing the radial force at the exit zone 410, with or without a reduced diameter, and modifying the compliance characteristics of the exit zone 410 may be used to reduce / reduce disruption or turbulence of blood flow.

[0062] 2E-2F are schematic side views illustrating several embodiments of a stent assembly 300 in which the ability of the stent structure to at least substantially approximate the native cross-sectional shape of the native vessel is achieved by varying the configuration and characteristics of the stent structure, with or without varying the radial forces between different stent structures, or with or without varying one or more zones. A stent structure or zone can have more struts 303 around its circumference than one or more other stent structures or zones. Increasing the number of struts 303 around its circumference can improve the stent structure's ability to assume the cross-sectional shape of the vessel in which it is deployed. For example, the inlet zone 310 can have a similar or greater number of struts 303 as one or more transition zones 320 / 350, which in turn can have a similar or greater number of struts 303 as one or more patency zones 370 / 390. The exit zone 410 can have similar, more, or fewer struts 303 than one or more of the patent zones 370 / 390. The stent structure length (longitudinal) can also affect the stent structure's ability to assume the cross-sectional shape of the vessel into which it is deployed. The longitudinal length of the stent structure (e.g., struts 303) can improve the stent structure's ability to assume the cross-sectional shape of the vessel into which it is deployed. Longer struts 303 (FIG. 2E) can provide improved conformance to the shape of the native vessel, but may reduce longitudinal flexibility along the zone or stent assembly 300 compared to shorter struts 303 (FIG. 2F) with the same material properties and cross-sectional dimensions. Shorter struts can provide a more gradual increase in radial force along the zone or region, greater longitudinal flexibility, and different conformance characteristics along the length of the stent assembly 300. Additionally, strut and link dimensions, properties (eg, heat treatment), etc. all affect radial force and conformance to the native vessel.For example, the inlet zone 310 can have struts 303 with lengths similar to or different from the lengths of one or more transition zones 320 / 350, and one or more transition zones 320 / 350 can have struts 303 with lengths similar to or different from the lengths of one or more patent zones 370 / 390. The outlet zone 410 can have struts 303 with lengths similar to or different from the lengths of one or more patent zones 370 / 390.

[0063] 2G is a side cross-sectional view of some embodiments of a stent assembly 300. In this embodiment, the stent assembly comprises an inlet zone 310, an optional first transition zone 330, an optional second transition zone 350, a first patent zone 370 (e.g., a first body zone), an intermediate transition zone 360, a second patent zone 390 (e.g., a second body zone), and an outlet zone 410 (not shown). Each zone can have one or more stent structures. For example, the inlet zone 310 can comprise an inlet stent structure 312, the first transition zone 330 can comprise a first transition stent structure 332, the second transition zone 350 can comprise a second transition stent structure 352, the first patent zone 370 can comprise a first patent stent structure 372, the intermediate transition zone 360 ​​can comprise an intermediate transition stent structure 362, the second patent zone 390 can comprise a second patent stent structure 392, and the exit zone 410 (not shown) can comprise an exit stent structure 412 (not shown). Compared to the adjacent first / second patent stent structures 372 / 392, the intermediate transition stent structure 362 can have a smaller cross-sectional area (intermediate transition zone contour 364), a smaller radial force, different length struts, and / or other different characteristics such that the intermediate transition stent structure 362 has different expansion and / or bending characteristics. The number of zones and the number of stent structures in each zone can vary depending on the application. Each stent structure can comprise at least one ring with struts 303 and / or at least one braided wire mesh. In some embodiments, the stent structures of at least some of the zones of stent assembly 300 can have a round (e.g., circular) cross-sectional shape when unconstrained in free space (i.e., in an unconstrained, fully expanded state), and when deployed in the vasculature, at least some of the stent structures of stent assembly 300 can bend to at least generally approximate the relative shape of a corresponding portion of a native blood vessel.In some embodiments, the stent structure of at least some bands of stent assembly 300 can have the relative shape of a corresponding portion of a blood vessel in an unconstrained, fully expanded state and when deployed in a vasculature. In some embodiments, the stent structure of at least some bands of stent assembly 300 can have the relative shape of a corresponding portion of a blood vessel in an unconstrained, fully expanded state and can bend to more closely approximate the relative shape of the corresponding portion of a blood vessel when deployed in a vasculature. In some embodiments, the stent structure of at least some bands of stent assembly 300 can have a smaller radial force in an unconstrained, fully expanded state so as not to expand the corresponding portion of a blood vessel and can bend to at least substantially approximate the normal difference in the connection between the superior sagittal sinus 130 and the transverse sinus 120 when deployed in a vasculature. Stent assembly 300 may also include interconnecting links 305 connecting adjacent stent structures together. Alternatively, adjacent stent structures may be directly connected to each other without the use of links 305. The number of links 305 connecting the stent structures can vary along the length of the stent assembly 300 .

[0064] 2H illustrates additional embodiments of the entrance zone 310 and first patent zone 370. For example, the first patent zone 370 can have a radial force of approximately 0.001 N / mm to approximately 3 N / mm, and the entrance zone 310 can have a radial force of 0.001 N / mm to approximately 1.5 N / mm. The patent zone 370 can have a radial force of approximately 0.2 N / mm to 1.3 N / mm near the nominal diameter (e.g., 5 mm, 6 mm, 7 mm, 8 mm), and a radial force of approximately 0.5 N / mm to 1.8 N / mm at a more constrained state, such as a 3.0 mm diameter. The inlet zone 310 can have a radial force of approximately 0.1 N / mm to 1.2 N / mm near the nominal diameter (e.g., 5 mm, 6 mm, 7 mm, 8 mm) and can have a radial force of approximately 0.3 N / mm to 1.5 N / mm at a more constrained state, such as a 3.0 mm diameter. Radiopaque markers 450 are shown at each end of the stent assembly 300. The illustrated stent assembly 300 has nine apices and three links 305 per stent structure, with three radiopaque markers 450 adjacent each end of the stent assembly 300. When deployed in a vessel, the patency zone 370 can have a generally circular cross-sectional shape 373, and the inlet zone 310 can have a generally triangular shape 314. In some embodiments, the stent assembly 300 can have only the inlet zone 310 and first patency zone 370 shown and described with respect to Figure 2H. In other embodiments, any of the stent assemblies 300 shown and described with respect to Figures 2A-2G can have the inlet zone 310 and first patency zone 370 shown and described with respect to Figure 2H.

[0065] 2I illustrates an embodiment of a stent assembly 300 similar to that depicted in FIG. 2H in which additional radiopaque markers 450 are adjacent the junction of the patent zone 370 and the inlet zone 310. The illustrated stent assembly 300 has nine apices and three links 305 per stent structure, with three radiopaque markers 450 at each end of the stent assembly 300 and three radiopaque markers 450 adjacent the junction of the patent zone 370 and the inlet zone 310.

[0066] FIG. 3 is a side view that schematically illustrates several embodiments of the exit zone 410 of the stent assembly 300, and FIG. 3-1 is a cross-sectional view of the second patent stent structure 392 and the exit stent structure 412. The exit stent structure 412 can be configured to cause blood flow to at least approximately have the cross-sectional shape and dimensions of the blood vessel at the exit of the stent assembly 300. Referring to FIG. 3-1, for example, the exit stent structure 412 can have a rounded rectangular exit shape 414 (e.g., four-sided, with straight or curved sides and rounded corners) to at least substantially approximate the cross-sectional shape of the native sigmoid sinus 110. The exit zone 410 can be similar in aspect to the inlet zone 310 and / or transition zones (330 / 350), such as having one or more stent structures with transitions (not shown) of various radial strengths and / or configurations (e.g., diameters and / or number and length of struts). The different radial forces and / or configurations along the stent assembly 300 from the inlet zone 310 to the outlet zone 410 provide a gradual transition that reduces or avoids disruptions in blood flow through the stented area and adjacent areas.

[0067] FIG. 4 is a schematic side view of some embodiments of the stent assembly 300 in which the transient pressure zone 430 has a transient stent structure 432, and FIG. 4-1 is a cross-sectional view of the patent stent structure 372, the exit stent structure 412, and the transient stent structure 432. In some embodiments, the transient pressure zone 430 has one or more transient stent structures 432, each having one or more radial forces and / or configurations (e.g., diameter and / or number and length of struts) that dynamically adapt to changes in cerebrospinal fluid pressure. Thus, the transient pressure zone 430 can allow a corresponding portion of the native blood vessel to adapt to rapid, transient increases in cerebrospinal fluid pressure. For example, the region within the transverse sinus 120 (FIG. 1) allows a reduction in vessel cross-sectional area during normal physiological spikes in cerebrospinal fluid pressure (e.g., during coughing). By having a transient pressure zone 430 adjacent to the first patent zone 370 and / or the second patent zone 390, the deployed stent assembly 300 can mimic the functionality of a native vessel within the stented portion of the vessel. The transient pressure zone 430 may have a radial force of approximately 0.0002 N / mm to approximately 1.5 N / mm, although other radial forces may be appropriate. FIG. 4-1 shows an example of a transient pressure zone contour 434 of a transient stent structure 432 during a temporary rise in cerebrospinal fluid pressure.

[0068] 5A and 5B are detailed views of several embodiments of bend regions 308 along individual struts 303 of any of the stent structure embodiments described herein. In the illustrated embodiment, FIG. 5A shows a single bend region 308 along a strut 303 of the outlet stent structure 412, and FIG. 5B shows several bend regions 308 along the struts 303 of the inlet stent structure 312. The bend region 308 can be along any of the struts 303 of other stent structures in any of the other zones, and a single stent structure can have several bend regions 308. The bend regions 308 can cause the stent assembly 300 to bend favorably in certain regions to better conform to the native vessel, thereby enhancing effective blood flow characteristics and simplifying implantation of the stent assembly 300. For example, the stent assembly 300 can have three or four bend regions 308 around the stent assembly 300 to better adapt the deployed stent assembly 300 to the shape of the native vessel. As a result, a single stent assembly 300 with sufficient bending region 308 can be implanted anywhere from the superior sagittal sinus 130 to the sigmoid sinus 110, significantly simplifying the process of stenting these vessels compared to implanting several individual stents. Thus, bending region 308 allows stent assembly 300 to both bend with the curvature of the vasculature (i.e., bending longitudinally) and adapt to the cross-sectional shape of the vasculature along the length of the stented region.

[0069] In any of the embodiments described herein, the stent structures may be connected to adjacent stent structures by at least one link 305. The shape, size, number, and positioning of the links 305 between the stent structures may be varied to obtain desired characteristics of the stent assembly 300 (e.g., radial force, longitudinal flexibility, resistance to longitudinal compression, delivery, etc.). For example, a greater number of links 305 per stent structure (e.g., one link 305 for one to three peaks or valleys of the stent structure) is expected to enable recapture of the stent assembly 300 over its portion. Fewer links 305 (e.g., one link 305 for three or more peaks or valleys of the stent structure) may improve the longitudinal flexibility of the stent assembly 300 to accommodate vessel curvature during delivery and / or after deployment.

[0070] In any of the embodiments disclosed herein, the links 305 can be straight, curved, zigzag, serpentine, or other suitable shape. The links 305 can have a bend for increased longitudinal flexibility and reduced longitudinal foreshortening of the stent assembly 300 when deployed. The links 305 can have a length of approximately 0.15 mm to approximately 20 mm or more, a width of approximately 0.0005 inches to approximately 0.015 inches or more, or 0.001 inches to 0.010 inches, and a thickness of approximately 0.0005 inches to approximately 0.015 inches or more, or 0.001 inches to 0.010 inches, depending on the desired functionality. The number of links 305 between stent structures affects not only the longitudinal flexibility of the stent assembly 300, but also the area of ​​coverage. A single link 305 connecting two adjacent stent structures can provide considerable longitudinal flexibility, and having a link 305 every few peaks / valleys of the stent structure (e.g., one link 305 every two to five peaks / valleys) provides additional coverage of the vessel and increases resistance to compression while maintaining some degree of flexibility. The number, shape, and dimensions of the links 305 can be selected to balance the longitudinal flexibility requirements of the amount of coverage with the desire to recapture the stent assembly 300 on a delivery catheter.

[0071] In certain embodiments, links 305 may be arranged in an apices-to-valley, apices-to-apices, apices-to-side, apices-to-side, apices-to-side, a crisscross, a boxcar, or other suitable configuration. An apices-to-valley configuration is a design configuration that reduces the amount of longitudinal foreshortening when stent assembly 300 is deployed, including an apices-to-valley configuration in which the apices and valleys are not aligned longitudinally along stent assembly 300. In some embodiments, all or a portion of stent assembly 300 may be recaptured by connecting links 305 at each apices of a strut-type stent structure to the corresponding apices of an adjacent strut-type stent structure in a braided configuration, a boxcar configuration, or other suitable configuration.

[0072] In any of the embodiments disclosed herein, at least some of the stent structures may be directly connected to one another using welding, adhesive, sutures, or other suitable fasteners. For example, stent structures 312, 332, 352, 372, 392, 412, and / or 432 may be directly connected to adjacent stent structures. In some embodiments, only some of the stent structures may be directly connected to one another using welding, adhesive, sutures, or other fasteners, while others of the stent structures are attached to adjacent stent structures using links 305.

[0073] 6 is a schematic side view of stent assembly 300 in which stent structures 312, 332, and 352 of zones 310, 330, and 350, respectively, are connected directly to one another without links 305, and stent structures 372 and 412 forming zones 370 and 410, respectively, are connected to one another with links 305. This configuration is useful for allowing a partially deployed stent assembly 300 to be recaptured. For example, stent assembly 300 can be partially deployed from a delivery catheter and then recaptured back into the delivery catheter if inlet zone 310 and / or transition zones 330 / 350 are not accurately positioned to position patency zone 370 at the narrowed portion of the blood vessel or if there is otherwise insufficient relief. Any number of stent structures can be directly connected to one another so that a desired length of stent assembly 300 can be partially deployed and recaptured for repositioning or removal. As previously described, any suitable number of links 305 may be used to allow for recapture of a partially or fully deployed stent assembly 300 .

[0074] 7A-7C are schematic side views of a stent assembly 300 in which the stent structure has a selected length or the struts 303 have a selected thickness, which can be applied to any embodiment disclosed herein. In some embodiments, the length of the stent structure may be varied in one or more zones to optimize the stent assembly 300 for a particular anatomical feature. For example, the length of the stent structure in some zones can be varied to accommodate more tortuous regions as well as the shape of the anatomy. This is expected to improve the interface with the vasculature and thereby enhance the characteristics and navigability of blood flow through the anatomy. FIGS. 7A and 7B illustrate some embodiments in which the stent structures 312, 332, and 352 in the inlet zone 310, first transition zone 330, and second transition zone 350, respectively, are longer than the stent structure 372 in the first patent zone 370 or the stent structure 392 in the second patent zone 390 (only in FIG. 7B). Longer stent structures and / or a greater number of circumferential struts 303 in the inlet zone 310 and transition zones 330 / 350 can cause the stent assembly 300 to at least substantially approximate the native cross-sectional shape of the native vessel. Conversely, as shown in FIG. 7C , the stent structures in the inlet zone 310 and / or transition zones 330 / 350 can be shorter than those in the patent zones 370 / 390 to provide a more gradual change in cross-sectional profile from the native vessel to the stent assembly 300 through the patent zone. The outlet zone 410 can also be longer or shorter than the patent zones 370 / 390 and can have a different number of struts 303 than the patent zones 370 / 390 for smoother blood egress from the stent assembly 300. The longitudinal length of the stent structure, when constrained, can be from about 0.25 mm to about 5 mm for shorter stent structures, and from about 0.5 mm to about 10 mm for longer stent structures.

[0075] 8A and 8B are side cross-sectional views of a stent assembly 300 in which some zones comprise braided fibers 304 and some zones comprise cut or etched structures with struts 303. In some embodiments, the stent assembly 300 can be, but is not limited to, a mesh, cut or etched material, braided material, or any combination of structures to form a non-rigid wall structure. In some embodiments, the fibers 304 comprise metal wire (e.g., nitinol or stainless steel wire), polymer strands, or other suitable materials, and combinations thereof. The fiber density and fiber thickness, along with the braid angle and the size of the pores between the fibers, can be selected so that each of the stent structures along the stent assembly 300 provides the desired radial force, shape, and flexibility for each zone.

[0076] 8A , inlet zone 310 has inlet stent structure 312 and transition zone 330 has transition stent structure 332, which may comprise a braided mesh having wire fibers 304 configured to have a generally circular cross-sectional shape in an unconstrained expanded state and configured to bend such that stent structures 312 and 332 at least substantially approximate the shape of the corresponding region of the blood vessel in which they are implanted. In some embodiments, such as when inlet zone 310 and / or first transition zone 330 are implanted in superior sagittal sinus 130 ( FIG. 1 ) or transverse sinus 120, inlet zone 310 and first transition zone 330 bend to have a three-sided cross-sectional shape (e.g., at least generally triangular) that at least substantially approximates the cross-sectional shape of superior sagittal sinus 130 and / or transverse sinus 120. In some embodiments, the inlet zone 310 and the first transition zone 330 have a three-sided shape (e.g., at least generally triangular) in their unconstrained expanded form and are also capable of bending to at least substantially approximate the generally triangular cross-sectional shape of the blood vessel in which they are implanted.

[0077] 8A , inlet stent structure 312 may have a lower radial force and / or may be otherwise configured to be more adaptable to the cross-sectional shape of the native vessel than transitional stent structure 332. For example, fibers 304 along inlet stent structure 312 may have an inlet braid angle 306, and fibers 304 along transitional stent structure 332 may have a transitional braid angle 336 that is less than inlet braid angle 306. As a result, transitional stent structure 332 may have a smaller pore size and a greater radial force than inlet stent structure 312. In some embodiments, additional fibers 304 may be woven into the braid along transitional stent structure 332 to impart a greater radial force and / or density than inlet stent structure 312. In some embodiments, the stent assembly may comprise an optional second transition zone 350 with a second transition stent structure 352 comprising fibers 304 braided at a second transition braid angle 356 that is less than the transition braid angle 336. Accordingly, the second transition stent structure 352 may have a greater radial force and / or density than the first transition stent structure 332. The second transition stent structure 352 may be attached to a first patent stent structure 372 in the first patency zone 370, which may comprise struts 303 formed from cut or etched hypotube, as previously described. As with other embodiments, the stent assembly 300 may include an optional second patent stent structure 392 defining a second patent zone 390, an optional transient stent structure 432 defining an optional transient pressure zone 430 (not shown), and / or an optional exit stent structure 412 defining an optional exit zone 410 (not shown).

[0078] 8B , one or more of stent structures 312 / 332, and optional stent structure 352, can increase in cross-sectional area in the downstream direction to first patent stent structure 372 in first patent zone 370. For example, in one embodiment, the diameter of stent assembly 300 can gradually increase through stent structures 312 / 332 and optional stent structure 352. In other embodiments, inlet stent structure 312 can have at least a substantially constant cross-sectional dimension in the unconstrained expanded state, and the cross-sectional dimension of one or both of first transitional stent structure 332 and second transitional stent structure 352 can increase to first patent stent structure 372. Stent assembly 300 can be fabricated (e.g., made from a round tube or mesh) to be essentially round when loaded into a delivery catheter, so that at least one or more portions of stent assembly 300 at least partially conform to the vessel wall when deployed. The stent assembly 300 may be fabricated to be essentially non-round in the deployed and / or collapsed state, e.g., not made round, such as a three-sided (e.g., generally triangular) and / or four-sided (e.g., rounded square) tube or mesh.

[0079] 9A-9D are schematic side views of a stent assembly 300 comprising fibers 304 braided from inlet to outlet. In some embodiments, the fibers 304 comprise metal wires (e.g., nitinol or stainless steel wires), polymer strands, or other suitable materials, and combinations thereof. The fiber density and fiber thickness, along with the braid angle and the size of the pores between the fibers, can be selected so that each of the stent structures along the stent assembly 300 provides the desired radial force, density, shape, ability to at least substantially conform to the native vessel, and flexibility for each zone. In some embodiments, for example, the stent assembly 300 can be a braided design with variable radial force along the length of the stent assembly 300, achieved by varying the braid angle along the length of the stent assembly 300. The inlet section of the stent assembly 300 can have a larger braid angle, which can result in a lower radial force and is expected to make the inlet section more compliant. In certain embodiments, stent assembly 300 may be a braided design with one or more strands added along its length to increase radial strength or density in specific sections. In certain embodiments, stent assembly 300 may be a braided design with one or more strands of thicker material woven into specific sections of stent assembly 300 to achieve variable radial strength.

[0080] 9A , in some embodiments, the braid angle of the fibers 304 decreases, which reduces the size of the pores between the fibers 304 from the inlet to the outlet of the stent assembly 300. For example, in the illustrated embodiment, the inlet stent structure 312 has an average braid angle 306 that is greater than the average braid angle 336 of the first transitional stent structure 332, which in turn is greater than the average braid angle 356 of the second transitional stent structure 352. Similarly, the average braid angle 356 can be greater than the average braid angle 376 of the first patency zone 370. The braid angle in each stent structure can be at least substantially constant throughout each stent structure, or the braid angle can vary along at least a portion of each stent structure. In some embodiments, braid angle 416 of outlet stent structure 412 is the same as or greater than braid angle 376 (as shown) of patent stent structure 372, while in other embodiments, braid angle 416 is greater than braid angle 376 such that the ostium size of outlet stent structure 412 is greater than that of patent stent structure 372. For example, braid angle 376 can be approximately the same as braid angle 336 or braid angle 306.

[0081] 9B, in some embodiments, the cross-sectional dimension of the stent assembly 300 can vary along the length of the braided material. For example, the braided material in the inlet zone 310 can have a smaller cross-sectional dimension than the cross-sectional dimension of the braided material in the adjacent transition zone 330 / (350). The cross-sectional dimension can vary gradually through some of the zones, or the cross-sectional dimension can be constant through some of the zones. For example, the cross-sectional dimension can gradually increase through the inlet zone 310 and the transition zone 330 / (350) and then remain at least substantially constant through the patency zone 370.

[0082] 9C , in some embodiments, the thickness of the fibers 304 can vary in different zones. For example, the fibers 304 in the inlet zone 310 can be thinner than the fibers 304 in the downstream zones 330, 350, and 370. The thickness of the fibers 304 can be at least substantially constant throughout the zones, or the thickness of the fibers 304 can vary gradually along the zone or along the length of some zones. As shown in FIG. 9C , the thickness of the fibers 304 can increase and the braid angle can decrease downstream from one zone to the next. This combination increases the flexibility of the inlet zone 310 to adapt to the cross-sectional shape of the native vessel, reducing or eliminating inlet flow disruption, which is expected to reduce or eliminate modification, while the patency zone 370 can have sufficient radial force to overcome the resistance of the native vessel wall and cerebrospinal fluid pressure at the stenosed portion of the vessel to restore patency.

[0083] 9D , any of the above embodiments may be applied to a stent assembly 300 having an intermediate transition zone 360 ​​positioned between a first patent zone 370 and a second patent zone 390. This configuration is particularly useful for a stent assembly 300 that spans from the superior sagittal sinus 130 to the sigmoid sinus 110. The stent assembly 300 may have a first patent zone 370 positioned at least partially in the superior sagittal sinus 130 and a second patent zone 390 positioned at least partially in the transverse sinus 120, and may extend into the sigmoid sinus 110. One or more patent zones may be directly connected or may include an intermediate transition zone 360 ​​and / or a transition pressure zone 430.

[0084] 10 is a side view that schematically illustrates a stent assembly 300 having a non-circular cross-sectional shape in an unconstrained, fully expanded state and / or when deployed in a vessel. Stent assembly 300 can have a three-sided cross-sectional shape (e.g., a relatively triangular shape) at inlet zone 310 (cross-section AA) and through one or more patent zones (e.g., patent zone 370) (cross-section BB), and can have a four-sided cross-sectional shape (e.g., a rounded square) at one or more patent zones (e.g., patent zone 390) and at outlet zone 410 (cross-section CC). Stent assembly 300 can have a combination of shapes in a collapsed, deployed state, such as a triangle in some regions and a square in other regions. In addition to the cross-sectional shape, the cross-sectional size can also vary along the length of stent assembly 300. For example, a non-round stent assembly 300 configured for stenting the transverse sinus 120 and sigmoid sinus 110 can cover the native vasculature from at or adjacent to the venous angle and / or from within the superior sagittal sinus 130, and can extend from there into the sigmoid sinus 110. Such a stent assembly 300 can be fabricated by cutting or etching struts 303 from round tubing with various diameters to accommodate the circumference of the vessel.

[0085] 11A-11C are cross-sectional views illustrating different cross-sectional shapes for portions of selected stent structures. At least a portion of the stent assembly 300 can be constructed with an overlapping stent structure 380 in a first configuration while constrained within the delivery catheter 200 (FIG. 11A). After deployment, the stent assembly 300 can expand to an expanded stent structure 382 of a larger circumference (FIG. 11B). After circumferential expansion of the expanded stent structure 382, ​​an external force on the stent assembly 300 can only compress (e.g., reduce the circumference of) the stent assembly 300 (recompressed stent structure 384) to a circumference greater than the circumference of the overlapping stent structure 380 but smaller than the circumference of the expanded stent structure 382 (FIG. 11C). This configuration provides a stent assembly 300 that has a low profile during deployment, expands to a desired circumference, and maintains a specified patency (minimum circumference) under extreme physiological conditions. For example, for a stent assembly 300 having a pre-deployment circumference of 3.8 mm when loaded into a delivery catheter, the stent assembly 300 can have a minimum post-deployment circumference of approximately 9 mm or greater to maintain an equivalent flow area in a vessel of approximately 3 mm diameter. This can be accomplished by having radial sections of the stent structure 380 overlap while in the delivery catheter 200, so that upon deployment (expanded stent structure 382), the stent structures do not overlap. Thereby, after deployment, compression of the stent structure (recompressed stent structure 384) prevents that overlap from occurring again, thereby maintaining a greater minimum cross-sectional area than when constrained within the delivery catheter 200.

[0086] As previously explained, in any of the embodiments described herein, the stent structure and links 305 can vary in various locations to adjust radial force, density, shape, ability to at least substantially conform to the native vessel, and flexibility. The inlet zone 310 typically has the lowest radial force and / or the greatest ability to at least substantially conform to the native vessel, the transition zones 330 / 350 have a greater radial force and / or a relatively lesser ability to at least substantially conform to the native vessel, and the patency zones 370 / 390 have an even greater radial force and / or an even lesser ability to at least substantially conform to the native vessel. At least a portion of the second patency zone 390 typically has a larger circumference in a deployed state within the vessel than a portion of the first patency zone 370, and the change in circumference can be gradual.

[0087] In any of the foregoing embodiments, the number of struts 303 per stent structure and / or the width and / or thickness of the struts 303 may be selected to provide the stent structure with a desired radial strength, density, shape, ability to at least substantially conform to the native vessel, flexibility, and size. The struts 303 may have a width from approximately 0.0005 inches to approximately 0.015 inches or more, and the struts 303 may have a thickness from approximately 0.0005 inches to approximately 0.015 inches or more. The size of the struts 303 may vary within a single stent structure; for example, the struts 303 on one longitudinal side of the stent structure may be different from the struts 303 on other longitudinal sides of the stent structure.

[0088] In any of the embodiments disclosed herein, the stent assembly 300 may comprise a self-expanding, shape-memory material, including NiTi or NiTi alloys (e.g., Ni, Ti, and Cr). Other suitable materials include stainless steel and biocompatible polymeric materials with the desired elasticity and spring force.

[0089] In any of the embodiments disclosed herein, the stent assembly 300 may include one or more radiopaque markers 450 to enhance visualization of the stent assembly 300 and / or regions of the stent assembly 300 (e.g., the edges, the patent zone, the transition zone, the exit zone, etc.) before, during, and / or after deployment. The radiopaque markers 450 may be made from, but are not limited to, tantalum, platinum, iridium, gold, tungsten, zirconium, or any combination or alloy thereof. The radiopaque markers 450 may be attached to the stent assembly 300 by adhesive bonding, crimping, crimping, wrapping, welding, braiding, or any method that secures the radiopaque marker 450. Construction of an example radiopaque marker 450 involves forming an opening, such as a relatively round opening, in the stent structure and crimping or crimping a radiopaque material (e.g., gold, tantalum) into the opening. The radiopaque marker 450 may be a coating applied to a selected portion of the stent assembly, or, as shown in FIG. 3, the radiopaque marker 450 may be one or more radiopaque strands 460 incorporated into any of the stent assemblies 300 shown in FIGS. 2A-10 to allow an operator to view one or more portions and / or the full length of the stent assembly 300.

[0090] In any of the embodiments disclosed herein, at least a portion of the stent assembly 300 may be coated with a material to enhance the efficacy and / or deliverability of the stent assembly 300. For example, such coatings may include anti-thrombogenic, anti-platelet, and / or anti-cell proliferation coatings to minimize or eliminate thrombus formation and tissue accumulation. Other coatings may include surface modifiers to alter the surface properties of the stent assembly 300 to increase or decrease lubricity / friction to aid in the delivery, deployment, recapture, placement, etc. of the stent assembly 300.

[0091] In any of the embodiments described herein, at least a portion of the stent assembly 300 can be constructed so that, after deployment, there is a minimum circumference (or diameter) to which all or at least a portion of the stent assembly 300 can be recompressed. This prevents all or at least a portion of the stent assembly 300 from being compressed (collapsed) below a cross-sectional area that would cause symptoms to recur due to high cerebrospinal fluid pressure. Such a configuration provides a stent assembly 300 that has a low profile during deployment, expands to a desired circumference, and maintains a specified patency (minimum circumference) under extreme physiological conditions. For example, for a stent assembly 300 that has a pre-deployment circumference of 3.8 mm when loaded into a delivery catheter, the stent assembly 300 can have a minimum post-deployment circumference of approximately 9 mm or greater to maintain an equivalent flow area in a vessel approximately 3 mm in diameter, which would generally reduce and / or eliminate symptoms.

[0092] In any of the embodiments described herein, the stent assembly 300 may be constructed so that upon partial or full deployment, the stent assembly 300 can be recaptured within the delivery catheter. For example, the stent assembly 300 can be in a blood vessel and at least partially deployed, and the patient can be evaluated for blood flow, resolution of tinnitus (e.g., pulsatile tinnitus), or other symptoms. If the results are unsatisfactory, the stent assembly 300 can be recaptured and removed, or repositioned to a different location in the vasculature. If repositioned, the patient can be reevaluated for the effectiveness of the new implantation location. Also, if the stent placement does not achieve the desired results after positioning or repositioning, the stent assembly 300 can be removed from the patient. When this is done, the patient is not required to follow medical requirements after stent assembly 300 implantation and does not have a permanent implant (stent assembly 300).

[0093] In any of the embodiments described herein, the circumference of the stent structure is sized to provide the desired collapsed diameter of the stent assembly 300 and also to provide the desired deployed circumference. Circumference is used instead of diameter when portions of the deployed stent assembly 300 are not round in cross section within the vessel, as this is more useful for determining the circumference of the deployed stent assembly 300 and for matching the circumference of the native vessel rather than matching the diameter of a circle. The circumference may be oversized or oversized, as determined by the physician. When deployed, the circumference may be constant along the length of the stent assembly 300 or may vary. For example, the circumference may vary between segments or zones, may have transitions, or may be partially or continuously variable. When collapsed for loading onto a delivery catheter or wire, the circumference of the stent structure may be 6F or 4F or less, or even smaller. For example, the circumference of the collapsed stent structure may be approximately 5.8 mm or less, or approximately 4.0 mm or less. The circumference of the deployed stent structure depends on the target vessel. When the stent assembly 300 is deployed from at or adjacent to the venous angle, or in the superior sagittal sinus 130 and extending into the sigmoid sinus 110, the size range may vary along the length of the stent assembly 300, as previously mentioned, such that the deployed stent assembly 300 has a circumference of approximately 5 mm to approximately 40 mm, or approximately 9 mm to approximately 35 mm. Various circumferences may be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, and 25 mm.

[0094] The length of the stent structure, as measured along the longitudinal axis of the stent assembly 300, is dimensioned to provide the desired compressed and deployed circumference as well as the necessary flexibility for maneuvering to the target location in the anatomy. The length of the stent structure along the stent assembly 300 can be varied to account for different parameters, such as radial force, area of ​​coverage, and the ability of the stent structure to assume the cross-sectional shape of the vessel.

[0095] In any of the embodiments described herein, the stent assembly 300 can be tailored to and deployed within a particular vasculature. For example, in some embodiments, a stent assembly 300 configured for stenting the transverse sinus 120 and sigmoid sinus 110 can be implanted into the vasculature from or adjacent to the venous angle, such as into the superior sagittal sinus 130, and can extend into the sigmoid sinus 110. In some embodiments, the stent assembly 300 from the venous angle to the sigmoid sinus 110 has a length of approximately 50 mm to approximately 120 mm, or approximately 60 mm to 100 mm. In some embodiments, a stent assembly 300 for implantation into the superior sagittal sinus 130 into the sigmoid sinus 110 has a length of approximately 80 mm to 300 mm, or approximately 100 mm to 180 mm. In some embodiments, a stent assembly 300 specifically configured for implantation in either the transverse sinus 120 alone or the sigmoid sinus 110 alone has a length of approximately 20 mm to approximately 80 mm, or approximately 30 mm to 50 mm. In some embodiments, a stent assembly 300 specifically configured for implantation in the superior sagittal sinus 130 alone may have a typical length of approximately 20 mm to approximately 200 mm, or approximately 40 mm to approximately 100 mm. In some embodiments, a stent assembly 300 for implantation in the superior sagittal sinus 130 is typically triangular in cross-section (like the transverse sinus 120) with a typical circumference of approximately 5 mm to approximately 40 mm, or approximately 9 mm to 26 mm. Various circumferences may be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, and 25 mm.

[0096] In some embodiments, an example configuration of a stent assembly 300 for use in the transverse sinus 120 extending into the sigmoid sinus 110 is as follows: the stent assembly 300 is constructed from NiTi and includes a stent structure and links 305, with an inlet zone 310 extending over a nominal length of approximately 3 mm to 15 mm, 5 mm to 12 mm (e.g., 10 mm), or 3 mm to 5 mm, and a nominal diameter (e.g., 5 mm, 6 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, 21 mm, 22 mm, 23 mm, 24 mm, 25 mm, 26 mm, 27 mm, 28 mm, 29 mm, 30 mm, 31 mm, 32 mm, 33 mm, 34 mm, 35 mm, 36 mm, 37 mm, 38 mm, 39 mm, 40 mm, 41 mm, 42 mm, 43 mm, 44 mm, 45 mm, 46 mm, 47 mm, 48 mm, 49 mm, 50 mm, 51 mm, 52 mm, 53 mm, 54 mm, 55 mm, 56 mm, 57 mm, 58 mm, 59 mm, 60 mm, 61 mm, 62 mm, 63 mm, 64 mm, 65 mm, 66 mm, 67 mm, 68 mm, 69 mm, 70 mm, 71 mm, 72 mm, 73 mm, 74 mm, 75 mm, 76 mm, 77 mm, 78 mm, 79 mm, 80 mm, 81 The stent structure 312 may have a radial force of approximately 0.1 N / mm to 1.2 N / mm near the stent diameter (mm), and a radial force of approximately 0.3 N / mm to 1.5 N / mm in a more constrained state of 3.0 mm diameter, with a longitudinal length of the stent structure 312 of approximately 0.15 mm to approximately 5 mm or approximately 2.3 mm, and a length of the links 305 of approximately 0.18 mm to approximately 6 mm or approximately 2.8 mm. The circumference of the inlet zone 310 may be approximately 16 mm to 26 mm. Various circumferences may be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, and 25 mm.

[0097] In any of the embodiments described herein, the stent assembly 300 can have a first transition zone 330 that extends over a nominal length of approximately 3 mm to 10 mm or 5 mm and has a radial force of approximately 0.001 N / mm to 2 N / mm or approximately 0.6 N / mm at the stent structure 332 adjacent the inlet zone 310, which can increase to approximately 0.5 N / mm to 1 N / mm or approximately 0.4 N / mm through the first transition zone 330. Such a first transition zone 330 can have a longitudinal length of the stent structure 312 of approximately 0.15 mm to approximately 5 mm or approximately 2.3 mm and a length of the link 305 of approximately 0.18 mm to approximately 6 mm or 1.8 mm to 2.8 mm. The circumference of the inlet zone 310 can be approximately 16 mm to 26 mm. The circumference of the first transition zone 330 can be from approximately 16 mm to approximately 26 mm. A variety of circumferences can be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, and 25 mm.

[0098] In any of the embodiments described herein, the stent assembly 300 can have a second transition zone 350 extending over a nominal length of approximately 0.3 mm to 10 mm or 5 mm and having a radial force of approximately 0.002 N / mm to 2.5 N / mm or approximately 0.6 N / mm at the stent structure 352 adjacent the first transition zone 330. The radial force can increase to approximately 1 N / mm to 3 N / mm or approximately 0.8 N / mm through the second transition zone 350. The second transition zone can have a longitudinal length of the stent structure 352 of approximately 0.15 mm to approximately 5 mm or 0.015 mm to 2.3 mm and a length of the links 305 of approximately 0.18 mm to approximately 6 mm or 1.8 mm to 2.8 mm. The circumference of the second transition zone 350 can be from approximately 16 mm to approximately 26 mm. A variety of circumferences can be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, and 25 mm.

[0099] In any of the embodiments described herein, the first patency zone 370 can extend over a nominal length of approximately 20 mm to 160 mm or 90 mm, and can have a radial force of approximately 0.2 N / mm to 1.2 N / mm near a nominal diameter (e.g., 5 mm, 6 mm, 8 mm), and a radial force of approximately 0.5 N / mm to 1.8 N / mm at a more constrained state of 3.0 mm diameter. The stent structure 372 of the first patency zone 370 can have a length of approximately 0.3 mm to approximately 5 mm or approximately 2.5 mm, and a link 305 length of approximately 0.35 mm to approximately 6 mm or approximately 2.7 mm. The circumference of the first patency zone 370 can be approximately 16 mm to approximately 26 mm. A variety of circumferences may be made available to accommodate a variety of patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, and 25 mm.

[0100] In any of the embodiments described herein, the stent assembly 300 can have an exit zone 410 extending over a length of approximately 3 mm to 15 mm or 8 mm and having a radial force of 0.05 N / mm to 3 N / mm or approximately 0.8 N / mm at its upstream end (e.g., adjacent the first patent zone 370 or the second patent zone 390), with the radial force of the exit zone 410 decreasing to approximately 0.05 N / mm to 2 N / mm or approximately 0.6 N / mm throughout the exit zone 410. The stent structure 412 of the exit zone 410 can have a length of approximately 0.15 mm to approximately 5 mm or approximately 2.3 mm, a link 305 length of approximately 0.15 mm to approximately 6 mm or approximately 2.8 mm, and a circumference of approximately 16 mm to approximately 28 mm. A variety of circumferences may be made available to accommodate a variety of patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, and 25 mm.

[0101] In any of the embodiments described herein, a stent assembly 300 for placement in the contralateral (non-dominant) transverse sinus 120, and optionally at least partially in the sigmoid sinus 110, is typically smaller in circumference than when placed for the dominant transverse sinus 120 of the same patient. Examples of stent assemblies 300 for use in the contralateral (non-dominant) transverse sinus 120 can be constructed as previously described with patent zone 370 lengths of approximately 20 mm to 60 mm or approximately 40 mm, and ostium zone 310 circumferences of approximately 9 mm to approximately 19 mm. Various circumferences can be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 9 mm, 12 mm, 16 mm, and 19 mm.

[0102] An example configuration of a stent assembly 300 for use in the superior sagittal sinus 130 is constructed from NiTi and includes a stent structure and links 305. The entrance zone 310 and transition zones 330 / 350 of such a stent assembly 300 extend over a nominal length of approximately 5 mm to 25 mm or approximately 10 mm and have a radial force of approximately 0.0005 N / mm to 0.8 N / mm or approximately 0.6 N / mm in the entrance zone 310, increasing through one or more optional transition zones to approximately 0.10 N / mm to 3 N / mm or approximately 0.8 N / mm in one of the patency zones 370. The stent structures of the entrance zone 310 and transition zones 330 / 350 have longitudinal lengths of approximately 0.15 mm to approximately 5 mm or 0.15 mm to approximately 2.3 mm, link 305 lengths of approximately 0.18 mm to approximately 6 mm or 0.18 mm to 2.8 mm, and circumferences of approximately 8 mm to approximately 22 mm. The first patency zone 370 of such a stent assembly 300 can extend over a nominal length of approximately 20 mm to 100 mm or approximately 40 mm and have a radial force of approximately 0.10 N / mm to 3 N / mm or approximately 1.0 N / mm. The stent structure 372 of the first patent zone 370 can have a length of approximately 0.15 mm to approximately 5 mm or approximately 2.3 mm, and a length of the links 305 of approximately 0.18 mm to approximately 6 mm or approximately 2.8 mm. The circumference of the first patent zone 370 can be approximately 9 mm to approximately 22 mm. Various circumferences can be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, and 22 mm.

[0103] In any of the embodiments described herein, a stent assembly 300 for placement in the superior sagittal sinus 130 through the sigmoid sinus 110 can have one or more patent zones 370 that can be separated by a distance, such as by a transition zone 330, with a first patent zone 370 positioned in the superior sagittal sinus 130 and a second patent zone 390 positioned in the transverse sinus 120 and extending into the sigmoid sinus 110.

[0104] In some embodiments, an example configuration of a stent assembly 300 for use in the superior sagittal sinus 130 extending into the sigmoid sinus 110 is as follows: The entrance zone 310 and transition zones 330 / 350 of such a stent assembly 300 extend over a nominal length of approximately 5 mm to 25 mm and have a radial force in the entrance zone 310 of approximately 0.0005 N / mm to 1.5 N / mm, or approximately 0.6 N / mm, increasing to approximately 0.10 N / mm to 3 N / mm, or approximately 0.8 N / mm, in one of the patency zones 370. The stent structures of the entrance zone 310 and transition zones 330 / 350 have longitudinal lengths of approximately 0.15 mm to approximately 5 mm or 0.15 mm to approximately 2.3 mm, link 305 lengths of approximately 0.18 mm to approximately 6 mm or 0.18 mm to 2.8 mm, and circumferences of approximately 8 mm to approximately 28 mm. The first patency zone 370 of such a stent assembly 300 can extend over a nominal length of approximately 20 mm to 100 mm or approximately 45 mm and have a radial force of approximately 0.10 N / mm to 3 N / mm or approximately 0.8 N / mm. The stent structure 372 of the first patency zone 370 can have a length of approximately 0.15 mm to approximately 5 mm or approximately 2.3 mm, and a length of the links 305 of approximately 0.15 mm to approximately 6 mm or approximately 2.8 mm. The circumference of the first patency zone 370 can be approximately 9 mm to approximately 21 mm. The intermediate transition zone 360 ​​can extend over a length of approximately 20 mm to 100 mm or approximately 30 mm and have a radial force of approximately 0.10 N / mm to 3 N / mm or approximately 0.6 N / mm. The second patency zone 390 can extend over a nominal length of approximately 20 mm to 160 mm or approximately 80 mm and have a radial force of approximately 0.10 N / mm to 3 N / mm or approximately 0.8 N / mm. The circumference of the second patent zone 390 can be from approximately 14 mm to approximately 26 mm.The optional exit zone 410 extends over a length of approximately 3 mm to 15 mm or 8 mm and has a radial force of 0.05 N / mm to 3 N / mm or approximately 0.6 N / mm. The circumference of the optional exit zone 410 is from approximately 16 mm to approximately 32 mm. Various circumferences may be made available to accommodate various patient vessel sizes, such as a range of sizes with circumferences of approximately 16 mm, 19 mm, 22 mm, 25 mm, and 28 mm.

[0105] Embodiments of the stent assembly 300 can be used in procedures for treating dural venous sinus stenosis, as described below. Vascular access is gained by placing a sheath into the femoral, brachial, cephalic, or jugular vein 100, and a guide catheter and associated guidewire 210 (e.g., 0.035 inch) is inserted into the sheath and advanced to the jugular bulb. The guide catheter can be positioned with its distal end at the jugular bulb, or it can extend within or beyond the sigmoid sinus 110. The guide catheter can even be positioned beyond the stenosis. The guidewire 210 and any guide catheter introducer are removed from the patient.

[0106] In any of the embodiments described herein, the delivery catheter 200 with the stent assembly 300 is loaded with a guidewire 210 (e.g., 0.014 inches) and inserted into the guide catheter. The delivery catheter 200 with the stent assembly 300 is advanced near the distal end of the guide catheter. The guidewire 210 is advanced until the distal end is beyond the desired location for deployment of the stent assembly 300. When the desired location for the ostial end of the stent assembly 300 is adjacent the venous angle, the guidewire 210 is advanced into the contralateral jugular vein, typically into either the superior sagittal sinus 130 or the contralateral transverse sinus 120. The delivery catheter 200 with the stent assembly 300 is then advanced over the guidewire 210 until the stent assembly 300 is in the desired location. Optionally, the delivery catheter 200 with the stent assembly 300 and the guidewire 210 can be moved together or independently in smaller increments through the vasculature. Optionally, the stent assembly 300 can be passed through a stenosis or positioned in the venous sinus system without the use of a guidewire 210. To position the stent assembly 300, including stenting the superior sagittal sinus 130, the guidewire 210 is advanced into the superior sagittal sinus 130 beyond the target location, and the delivery catheter 200 with the stent assembly 300 is advanced to the desired location within the superior sagittal sinus 130.

[0107] Once the stent assembly 300 is in the desired location, it is generally only partially deployed (e.g., in one or more of the entrance zone 310 and / or transition zones 330 / 350) so that a distal portion of the stent assembly 300 engages the vessel wall. The location of the stent assembly 300 may then be evaluated. Optionally, if the stent assembly 300 is not in the desired location, the distal portion of the stent assembly 300 may be recaptured within the delivery catheter 200 and repositioned at another location, as previously described. If the stent assembly 300 is in the desired location, deployment continues until a sufficient length of the stent assembly 300 has been deployed so that the effectiveness of the implanted device can be evaluated. Optionally, if the results are undesirable, the stent assembly 300 may be recaptured and, optionally, removed from the patient or repositioned. If the results are desirable, the stent assembly 300 is fully deployed.

[0108] Optionally, the stent assembly 300 may be equipped with a system that senses intravascular pressure in the proximal and / or distal portions of the target vessel to determine whether deployment of the stent assembly 300 is warranted or whether adequate treatment is achieved after or during deployment.

[0109] Optionally, the guidewire 210 can be positioned using a microcatheter into the superior sagittal sinus 130, the contralateral transverse sinus 120, or the contralateral jugular vein 100. The microcatheter is then removed and the stent assembly 300 is then loaded onto the wire and threaded into position.

[0110] After deploying the stent assembly 300, the delivery catheter 200 and guidewire 210 are retracted, either sequentially or simultaneously, into the guide catheter and removed from the patient. The guide catheter remains in the patient while diagnostics may be performed to assess placement, physiological parameters, symptom relief, etc. The guide catheter is then removed from the patient, followed by the sheath. The access site is then closed.

[0111] [Example] The present technology is described according to various aspects, for example, as described below. Various examples of aspects of the present technology are described as numbered examples (1, 2, 3, etc.) for convenience. These are provided as examples and do not limit the present technology. It should be noted that any of the dependent examples can be combined in any combination and can be placed into their own independent examples. Other examples may be presented in an equivalent manner. 1. A stent assembly for implantation in a blood vessel, comprising: an inlet zone comprising at least one inlet stent structure, the inlet stent structure having an inlet radial force configured to self-expand and at least partially conform to an at least substantially non-circular cross-sectional shape of the vessel; a patent zone having at least one patent stent structure positioned distal to the ostium stent structure, the patent stent structure being self-expanding and having a patent radial force greater than the ostium radial force, the patent stent structure being coupled to the ostium stent structure such that the ostium stent structure is configured to be positioned upstream from a stenosis of the lumen along the blood vessel, and the patent stent structure is configured to be positioned at the stenosis of the blood vessel lumen; A stent assembly comprising: 2. the ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the vessel; The stent assembly of Example 1, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend into a generally triangular shape when expanded into contact with a blood vessel. 3. The inlet radial force of the inlet stent structure is approximately 0.0005 N / mm to 2 N / mm; The stent assembly of Examples 1 or 2, wherein the patent radial force of the patent stent structure is approximately 0.001 N / mm to 3 N / mm. 4. The inlet radial force of the inlet stent structure is approximately 0.001 N / mm to 1.5 N / mm; The stent assembly of any of Examples 1-3, wherein the patent radial force of the patent stent structure is from approximately 0.3 N / mm to 2.0 N / mm. 5. The stent assembly of any of Examples 1-4, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular cross-sectional shape when expanded into contact with the blood vessel. 6. The stent assembly of any of Examples 1-5, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to deform to a generally triangular cross-sectional shape when expanded into contact with a generally triangular shaped cross-section of the blood vessel. 7. The stent assembly of any of Examples 1-6, wherein the inlet stent structure has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to conform to the blood vessel when expanded into contact with the blood vessel. 8. The stent assembly of any of Examples 1-7, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and has a generally circular cross-sectional shape when expanded in contact with a blood vessel. 9. The stent assembly of any of Examples 1-8, wherein the patent radial force of the patent stent structure is configured to limit vascular constriction when extrinsic compression or increased intracranial pressure occurs, which may cause enlargement of the arachnoid granulations. 10. The stent assembly of any of Examples 1-9, further comprising an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force. 11. The stent assembly of any of Examples 1-10, further comprising a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure. 12. The stent assembly of any of Examples 1-11, further comprising a transient pressure zone adjacent the patency zone and having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure. 13. The stent assembly of any of Examples 1-12, wherein the inlet stent structure comprises an inlet annulus having struts, and the patent stent structure comprises a patent annulus having struts. 14. The stent assembly of any of Examples 1-12, wherein the inlet stent structure comprises a plurality of inlet annuli having struts, and the patent stent structure comprises a plurality of patent annuli having struts. 15. The stent assembly of any of Examples 1-12, wherein the inlet stent structure comprises a braided mesh and the patent stent structure comprises a patent annulus having struts. 16. An exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force; a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure; a transient pressure zone associated with the patency zone, the transient pressure zone having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure; The stent assembly of any of Examples 1 to 15, further comprising: 17. A transitional stent structure is connected to a distal portion of the ostial stent structure and a proximal portion of the patent stent structure; 17. The stent assembly of Example 16, wherein the outlet stent structure is coupled to a distal portion of the patent stent structure and a proximal portion of the outlet stent structure. 18. The stent assembly of any of Examples 1-17, wherein the patent zone defines a first patent zone having a first patent stent structure, and the stent assembly further comprises a second patent zone having a second patent stent structure. 19. The stent assembly of Example 18, wherein the first patent stent structure has a first expansion characteristic and the second patent stent structure has a second expansion characteristic. 20. The stent assembly of Example 18, wherein the first patent stent structure has a first patent radial force and the second patent stent structure has a second patent radial force that is different from the first patent radial force. 21. The stent assembly of Example 18, further comprising an intermediate transition zone having intermediate expansion characteristics different from the first expansion characteristic of the first patent stent structure and the second expansion characteristic of the second patent stent structure, such that the intermediate transition zone is more flexible than the first patent stent structure and the second patent stent structure. 22. The stent assembly of any of Examples 1-21, wherein the ostial stent structure and the first patent stent structure are configured to be positioned in the superior sagittal sinus and the second patent stent structure is configured to be positioned at least partially in the transverse sinus, and the stent assembly further comprises a transition zone having a transition stent structure with a lower radial force than the first patent stent structure or the second patent stent structure. 23. The stent assembly of any of Examples 1-22, wherein the patent zone comprises at least one patent stent structure having a patent radial force that is self-expanding and configured to expand to engage arachnoid granulations within the lumen of the blood vessel and restore flow within the lumen of the blood vessel. 24. A stent assembly for implantation in a blood vessel, comprising: an inlet zone comprising at least one inlet stent structure, the inlet stent structure being self-expanding and having an inlet radial force that compresses with increasing external pressure on the vessel; a patent zone having at least one patent stent structure, the patent stent structure being self-expanding and having a patent radial force greater than an inlet radial force, the patent radial force being sufficient to maintain vascular patency when external pressure in the vessel increases; A stent assembly comprising: 25. The ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the vessel; 25. The stent assembly of Example 24, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with a blood vessel. 26. The ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the vessel; The stent assembly of Examples 24 or 25, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and a generally circular cross-sectional shape when expanded in contact with a blood vessel, whereby a portion of the blood vessel in contact with the patent stent structure at least substantially conforms to the generally circular cross-sectional shape of the patent stent structure. 27. The inlet radial force of the inlet stent structure is approximately 0.0005 N / mm to 2 N / mm; The stent assembly of any of Examples 24-26, wherein the patent radial force of the patent stent structure is approximately 0.001 N / mm to 3 N / mm. 28. The stent assembly of any of Examples 24-27, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular cross-sectional shape when expanded into contact with the blood vessel. 29. The stent assembly of any of Examples 24-28, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to deform to a generally triangular cross-sectional shape when expanded into contact with a generally triangular cross-section of the blood vessel. 30. The stent assembly of any of Examples 24-29, wherein the inlet stent structure has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to conform to the blood vessel when expanded into contact with the blood vessel. 31. The stent assembly of any of Examples 24-29, wherein the patent radial force of the patent stent structure is configured to limit constriction of the blood vessel when external pressure on the blood vessel increases. 32. The stent assembly of any of Examples 24-31, further comprising an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force. 33. The stent assembly of any of Examples 24-32, further comprising a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure. 34. The stent assembly of any of Examples 24-33, further comprising a transient pressure zone adjacent the patency zone and having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure. 35. The stent assembly of any of Examples 24-34, wherein the inlet stent structure comprises an inlet annulus having struts, and the patent stent structure comprises a patent annulus having struts. 36. The stent assembly of any of Examples 24-35, wherein the inlet stent structure comprises a plurality of inlet annuli having struts, and the patent stent structure comprises a plurality of patent annuli having struts. 37. The stent assembly of any of Examples 24-36, wherein the inlet stent structure comprises a braided mesh and the patent stent structure comprises a patent annulus having struts. 38. An exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force; a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure; a transient pressure zone between the patency zone and the exit zone, the transient pressure zone having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure; The stent assembly of any one of Examples 24 to 37, further comprising: 39. A transitional stent structure is connected to a distal portion of the ostial stent structure and a proximal portion of the patent stent structure; The stent assembly of any of Examples 24-38, wherein the exit stent structure is coupled to a distal portion of the patent stent structure and a proximal portion of the exit stent structure. 40. The stent assembly of any of Examples 24-39, wherein the patent zone defines a first patent zone having a first patent stent structure, and the stent assembly further comprises a second patent zone having a second patent stent structure. 41. The stent assembly of any of Examples 24-40, wherein the first patent stent structure has a first expansion characteristic and the second patent stent structure has a second expansion characteristic. 42. The stent assembly of Example 40, wherein the first patent stent structure has a first patent radial force and the second patent stent structure has a second patent radial force that is different from the first patent radial force. 43. The stent assembly of Example 40, further comprising an intermediate transition zone having intermediate expansion characteristics different from the first expansion characteristic of the first patent stent structure and the second expansion characteristic of the second patent stent structure, such that the intermediate transition zone is more flexible than the first patent stent structure and the second patent stent structure. 44. A stent assembly for implantation in a blood vessel, comprising: an entrance zone comprising at least one entrance stent structure, the entrance stent structure being self-expanding and configured to at least substantially conform to the non-circular cross-sectional shape of a portion of the blood vessel in contact with the entrance stent structure when the entrance stent structure expands; a patent zone having at least one patent stent structure, the patent stent structure configured to self-expand and expand to an expanded shape that is different from the non-circular cross-sectional shape of the blood vessel, whereby a portion of the blood vessel in contact with the patent stent structure at least substantially conforms to the expanded shape of the patent stent structure, the patent stent structure coupled to an ostium stent structure such that the ostium stent structure is configured to be positioned upstream from the stenosis along the blood vessel and the patent stent structure is configured to be positioned at a compromised point in the lumen; A stent assembly comprising: 45. The inlet stent structure has an inlet radial force; 45. The stent assembly of Example 44, wherein the patent stent structure has a patent radial force that is greater than the inlet radial force. 46. ​​The ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the vessel; 46. ​​The stent assembly of Examples 44 or 45, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with a blood vessel. 47. The inlet radial force of the inlet stent structure is approximately 0.0005 N / mm to 2 N / mm; The stent assembly of any of Examples 44-46, wherein the patent radial force of the patent stent structure is approximately 0.001 N / mm to 3 N / mm. 48. The stent assembly of any of Examples 44-47, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular cross-sectional shape when expanded into contact with the blood vessel. 49. The stent assembly of any of Examples 44-48, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to deform to a generally triangular cross-sectional shape when expanded into contact with a generally triangular cross-section of the blood vessel. 50. The stent assembly of any of Examples 44-49, wherein the inlet stent structure has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to conform to the blood vessel when expanded into contact with the blood vessel. 51. The stent assembly of any of Examples 44-50, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and has a generally circular cross-sectional shape when expanded in contact with a blood vessel. 52. The stent assembly of any of Examples 44-51, wherein the patent radial force of the patent stent structure is configured to limit constriction of the blood vessel when external pressure on the blood vessel increases. 53. The stent assembly of any of Examples 44-52, further comprising an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force. 54. The stent assembly of any of Examples 44-53, further comprising a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure. 55. The stent assembly of any of Examples 44-54, further comprising a transient pressure zone adjacent the patency zone and having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure. 56. The stent assembly of any of Examples 44-55, wherein the inlet stent structure comprises an inlet annulus having struts, and the patent stent structure comprises a patent annulus having struts. 57. The stent assembly of any of Examples 44-56, wherein the inlet stent structure comprises a plurality of inlet annuli having struts, and the patent stent structure comprises a plurality of patent annuli having struts. 58. The stent assembly of any of Examples 44-57, wherein the inlet stent structure comprises a braided mesh and the patent stent structure comprises a patent annulus having struts. 59. An exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force; a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure; a transient pressure zone associated with the patency zone, the transient pressure zone having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure; The stent assembly of any of Examples 44 to 58, further comprising: 60. A transitional stent structure is connected to a distal portion of the ostial stent structure and a proximal portion of the patent stent structure; 59. The stent assembly of any of Examples 44-59, wherein the exit stent structure is coupled to a distal portion of the patent stent structure. 61. The stent assembly of any of Examples 44-60, wherein the patent zone defines a first patent zone having a first patent stent structure, and the stent assembly further comprises a second patent zone having a second patent stent structure. 62. The stent assembly of any of Examples 44-61, wherein the first patent stent structure has a first expansion characteristic and the second patent stent structure has a second expansion characteristic. 63. The stent assembly of Example 61, wherein the first patent stent structure has a first patent radial force and the second patent stent structure has a second patent radial force that is different from the first patent radial force. 64. The stent assembly of Example 61, further comprising an intermediate transition zone having intermediate expansion characteristics different from the first expansion characteristic of the first patent stent structure and the second expansion characteristic of the second patent stent structure, such that the intermediate transition zone is more flexible than the first patent stent structure and the second patent stent structure. 65. The stent assembly of any of Examples 44-63, wherein the ostial stent structure and the first patent stent structure are configured to be positioned in the superior sagittal sinus and the second patent stent structure is configured to be positioned at least partially in the transverse sinus, and the stent assembly further comprises a transition zone having a transition stent structure with a lower radial force than the first patent stent structure or the second patent stent structure. 66. A method of treating symptoms caused by stenosis along a dural venous sinus, comprising: positioning the stent assembly in the dural venous sinus such that (a) an entrance zone of the stent assembly is at a location upstream from a compromised point of the lumen in the dural venous sinus relative to blood flow through the dural venous sinus, and (b) a patent zone of the stent assembly is at a stenosed portion of the dural venous sinus; expanding an ostial stent structure in the ostial zone at an upstream location to have a triangular cross-sectional shape that at least substantially approximates the generally triangular cross-sectional shape of a dural venous sinus, the ostial stent structure having an ostial radial force; expanding the patent stent structure in the patent zone at the stenotic portion of the dural venous sinus such that the patent stent structure increases a cross-sectional area of ​​the stenotic portion of the dural venous sinus, the patent stent structure having a patent radial force greater than the inlet radial force; A method comprising: 67. The method of Example 66, wherein the ostial stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and wherein expanding the ostial stent structure includes self-expanding the ostial stent structure such that the ostial stent structure at least substantially approximates the triangular cross-sectional shape of the upstream location. 68. The method of Example 66 or 67, wherein the ostial stent structure is coupled to the patent stent structure prior to positioning the stent assembly in the dural venous sinus such that a single stent assembly is positioned at a location upstream of the dural venous sinus and along the narrowed portion thereof. 69. The symptom is papilledema, as in any of Examples 66-68. 70. The symptom is pulsatile tinnitus, as in any of Examples 66-68. 71. The symptom is headache, as in any of Examples 66-68. 72. The ostial stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the ostial stent structure includes self-expanding the ostial stent structure such that the ostial stent structure at least substantially approximates a triangular cross-sectional shape at the upstream location; 72. The method of any of Examples 66-71, wherein the patent stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and wherein expanding the patent stent structure comprises allowing the patent stent structure to self-expand such that the patent stent structure at least substantially approximates a triangular cross-sectional shape of the stenosed portion of the dural venous sinus. 73. The method of Example 72, wherein, upon expansion, the triangular cross-sectional shape of the ostial stent structure is different from the triangular cross-sectional shape of the patent stent structure. 74. The method of any of Examples 66-73, wherein the step of positioning the stent assembly in the dural venous sinus further includes positioning an exit zone of the stent assembly at a location downstream from the narrowed portion of the dural venous sinus relative to blood flow through the dural venous sinus, the exit zone having an exit stent structure with an exit radial expansion force greater / less than the patency expansion force. 75. The method of Example 74, further comprising expanding the outlet stent structure of the outlet zone at the downstream location so that the outlet stent structure has a cross-sectional dimension that approximates the cross-sectional dimension at the downstream location.

[0112] Alternate embodiments may be devised without departing from the spirit or scope of the present technology. Additionally, well-known elements of the system, apparatus, and method embodiments have not been described in detail or have been omitted so as not to obscure the relevant details of the systems, apparatus, and methods.

[0113] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The terms "comprises," "comprising," or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements, but may also include other elements not expressly listed or other elements inherent to such process, method, article, or apparatus. The use of an element following "comprising a" does not, without further constraints, preclude the presence of additional identical elements in the process, method, article, or apparatus that comprises that element. The terms "including" and / or "having," as used herein, are defined as "comprising" (i.e., open language). The terms "a" or "an," as used herein, are defined as one or more than one. The term "plurality," as used herein, is defined as two or more than two. The term "other," as used herein, is defined as at least a second or more. The description may use the term "embodiments," which may each refer to one or more of the same or different embodiments.

[0114] When the terms "coupled" and "connected," along with their derivatives, are used, these terms are not intended as synonyms for each other. For example, "connected" may be used to indicate that two or more elements are in direct physical or electrical contact with each other. "Coupled" can mean that two or more elements are in direct physical or electrical contact (e.g., directly coupled), or that two or more elements are not in direct contact with each other, but still cooperate or interact with each other (e.g., indirectly coupled).

[0115] For purposes of description, a phrase in the form "A / B," or in the form "A and / or B," or in the form "at least one of A and B" means (A), (B), or (A and B), where A and B are variables designating specific objects or attributes. When used, this phrase is intended and defined hereby as a selection of A, B, or both A and B, similar to the term "and / or." When more than two variables are present in such a phrase, the phrase is defined hereby to include only one of the variables, any one of the variables, any combination of the variables, and all of the variables; for example, a phrase in the form "at least one of A, B, and C" means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C).

[0116] Relationship terms such as first and second, above and below, etc., may be used only to distinguish one entity or act from another entity or act and do not necessarily require or imply any actual relationship or order between such entities or acts. The descriptions may use perspective-based descriptions such as above / below, after / before, top / bottom, and proximal / distal. Such descriptions are used merely for ease of review and are not intended to constrain the application of the disclosed embodiments. Various operations may be collectively described as multiple individual operations in a manner that can aid in understanding the embodiments, but the order of description should not be construed to imply that these operations are order-dependent.

[0117] As used herein, the terms "about" or "approximately" apply to all numerical values, whether or not explicitly indicated. These terms generally refer to a range of numbers that one of ordinary skill in the art would consider equivalent to the stated value (i.e., having the same function or result). In many instances, these terms may include numbers that are rounded to the nearest significant figure. As used herein, the terms "substantial" and "substantially" mean that, when comparing various parts with each other, the compared parts are equal or sufficiently close in dimension that one of ordinary skill in the art would consider them the same. As used herein, "substantial" and "substantially" are not limited to a single dimension but explicitly include a range of values ​​for the compared parts. A range of values, both above and below (e.g., "+ / -", higher / lower, or larger / smaller), includes variations that one of ordinary skill in the art would find to be a reasonable tolerance for the referenced parts.

[0118] Various embodiments of systems, devices, and methods have been described, and many features are similar in many of the different embodiments. To avoid redundancy, repeated descriptions of these similar features may not be made in some circumstances. However, it will be understood that descriptions of features appearing first apply to similar features described later, and thus each respective description is incorporated without such repetition.

[0119] From the foregoing, it will be understood that, although specific embodiments of the present disclosure have been described herein for purposes of illustration, various modifications can be made without departing from the scope of the disclosure. Accordingly, the present disclosure is not limited except as by the appended claims. [Explanation of symbols]

[0120] 100 Internal jugular vein 110 Sigmoid sinus 120 Transverse sinus 125 Arachnoid Granules 130 Superior sagittal sinus 150 Narrowed area 160 Upstream Location 170 bones 172 Brain 174 Cerebrospinal fluid 200 Delivery Catheter 210 Guidewire 300 Stent assembly 303 Post 304 Braided Fiber 305 Link 306 Average braid angle of inlet stent structure 312 308 bending area 310 Inlet Stent Zone 312 Inlet stent structure 314 Generally triangular in shape, generally triangular in cross section 330 First Transition Zone 332 First transitional stent structure 334 First Transition Zone Contour 336 average braid angle of first transitional stent structure 332 350 Second Transition Zone 352 Second Transitional Stent Structure 354 Second Transition Zone Contour 356 average braid angle of second transitional stent structure 352 360 Intermediate Transition Zone 362 Intermediate Transition Stent Structure 364 Intermediate Transition Zone Contour 370 First patent zone 372 First patent stent structure 373 Generally circular cross-sectional shape 374 Triangular shape, generally circular cross section 376 Average braid angle of first patent zone 370 380 Overlapping stent structure 382 Expanded stent structure 384 Recompressed stent structure 390 Second patent zone 392 Second patent stent structure 394 Mostly or generally circular cross-sectional shape 410 Exit Bandwidth 412 Exit Stent Structure 414 Rounded square cross section 416 Braid angle of exit stent structure 412 430 Transient Pressure Zone 432 Transitional Stent Structure 450 Radiopaque Marker P Increased cerebrospinal fluid pressure

Claims

1. 1. A stent assembly for implantation in a blood vessel, comprising: an inlet zone comprising at least one inlet stent structure, the inlet stent structure having an inlet radial force configured to self-expand and at least partially conform to a non-circular cross-sectional shape of the vessel; a patent zone having at least one patent stent structure positioned distal to the ostial stent structure, the patent stent structure being self-expanding and having a patent radial force greater than the ostial radial force, the patent stent structure being coupled to the ostial stent structure such that the ostial stent structure is configured to be positioned along the blood vessel upstream from a stenosis of a lumen, and the patent stent structure is configured to be positioned at the stenosis of the blood vessel lumen; A stent assembly comprising:

2. the ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the blood vessel; 10. The stent assembly of claim 1, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the blood vessel.

3. the inlet radial force of the inlet stent structure is approximately 0.0005 N / mm to 2 N / mm; 3. The stent assembly of claim 1 or 2, wherein the patent radial force of the patent stent structure is approximately 0.001 N / mm to 3 N / mm.

4. the inlet radial force of the inlet stent structure is approximately 0.001 N / mm to 1.5 N / mm; 4. The stent assembly of claim 1, wherein the patent radial force of the patent stent structure is approximately 0.3 to 2.0 N / mm.

5. 5. The stent assembly of claim 1, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular cross-sectional shape when expanded into contact with a blood vessel.

6. 6. The stent assembly of claim 1, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to deform to a generally triangular cross-sectional shape when expanded into contact with a generally triangular cross-section of the blood vessel.

7. 7. The stent assembly of claim 1, wherein the inlet stent structure has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to conform to the blood vessel when expanded into contact with the blood vessel.

8. 8. The stent assembly of claim 1, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and has a generally circular cross-sectional shape when expanded into contact with the blood vessel.

9. 9. The stent assembly of claim 1, wherein the patent radial force of the patent stent structure is configured to limit constriction of the blood vessel when increased intracranial pressure occurs that may cause extrinsic compression or expansion of the arachnoid granulations.

10. 10. The stent assembly of claim 1, further comprising an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force.

11. 11. The stent assembly of claim 1, further comprising a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure.

12. 12. The stent assembly of claim 1, further comprising a transient pressure zone adjacent the patency zone and having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure.

13. 13. A stent assembly according to any one of claims 1 to 12, wherein the inlet stent structure comprises an inlet annulus having struts and the patent stent structure comprises a patent annulus having struts.

14. 13. A stent assembly according to any one of claims 1 to 12, wherein the inlet stent structure comprises a plurality of inlet annuli having struts, and the patent stent structure comprises a plurality of patent annuli having struts.

15. 13. The stent assembly of claim 1, wherein the inlet stent structure comprises a braided mesh and the patent stent structure comprises a patent annulus having struts.

16. an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force; a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure; a transient pressure zone associated with the patency zone, the transient pressure zone having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure; 16. The stent assembly of claim 1, further comprising:

17. the transitional stent structure is connected to a distal portion of the ostial stent structure and a proximal portion of the patent stent structure; 17. The stent assembly of claim 16, wherein the outlet stent structure is coupled to a distal portion of the patent stent structure and a proximal portion of the outlet stent structure.

18. 18. The stent assembly of claim 1, wherein the patent zone defines a first patent zone having a first patent stent structure, and the stent assembly further comprises a second patent zone having a second patent stent structure.

19. 20. The stent assembly of claim 18, wherein the first patent stent structure has a first expansion characteristic and the second patent stent structure has a second expansion characteristic.

20. 20. The stent assembly of claim 18, wherein the first patent stent structure has a first patent radial force and the second patent stent structure has a second patent radial force different from the first patent radial force.

21. 20. The stent assembly of claim 19, further comprising an intermediate transition zone having intermediate expansion characteristics different from the first expansion characteristic of the first patent stent structure and the second expansion characteristic of the second patent stent structure, such that the intermediate transition zone is softer than the first patent stent structure and the second patent stent structure.

22. 22. The stent assembly of any one of claims 1 to 21, wherein the ostium stent structure and first patent stent structure are configured to be positioned in the superior sagittal sinus and the second patent stent structure is configured to be positioned at least partially in the transverse sinus, and the stent assembly further comprises a transition zone having a transition stent structure with a lower radial force than the first patent stent structure or the second patent stent structure.

23. 23. The stent assembly of any one of claims 1 to 22, wherein the patent zone comprises at least one patent stent structure having a patent radial force configured to self-expand and expand to engage arachnoid granulations within the lumen of the blood vessel and restore flow within the lumen of the blood vessel.

24. 1. A stent assembly for implantation in a blood vessel, comprising: an inlet zone comprising at least one inlet stent structure, the inlet stent structure being self-expanding and having an inlet radial force that compresses with increasing external pressure on the vessel; a patent zone having at least one patent stent structure, the patent stent structure being self-expanding and having a patent radial force greater than the inlet radial force, the patent radial force being sufficient to maintain patency of the vessel when external pressure in the vessel increases; A stent assembly comprising:

25. the ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the blood vessel; 25. The stent assembly of claim 24, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the blood vessel.

26. the ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the blood vessel; 26. A stent assembly according to claim 24 or 25, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and a generally circular cross-sectional shape when expanded in contact with the blood vessel, whereby a portion of the blood vessel in contact with the patent stent structure at least substantially conforms to the generally circular cross-sectional shape of the patent stent structure.

27. the inlet radial force of the inlet stent structure is approximately 0.0005 N / mm to 2 N / mm; 27. The stent assembly of any one of claims 24 to 26, wherein the patent radial force of the patent stent structure is approximately 0.001 N / mm to 3 N / mm.

28. 28. A stent assembly according to any one of claims 24 to 27, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular cross-sectional shape when expanded into contact with a blood vessel.

29. 29. The stent assembly of any one of claims 24 to 28, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to deform to a generally triangular cross-sectional shape when expanded into contact with a generally triangular cross-section of the blood vessel.

30. 30. A stent assembly according to any one of claims 24 to 29, wherein the inlet stent structure has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to conform to the blood vessel when expanded into contact with the blood vessel.

31. 30. The stent assembly of any one of claims 24 to 29, wherein the patent radial force of the patent stent structure is configured to limit constriction of the blood vessel when external pressure on the blood vessel increases.

32. 32. The stent assembly of any one of claims 24 to 31, further comprising an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force.

33. 33. The stent assembly of any one of claims 24 to 32, further comprising a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure.

34. 34. The stent assembly of any one of claims 24 to 33, further comprising a transient pressure zone adjacent the patency zone and having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure.

35. 35. A stent assembly according to any one of claims 24 to 34, wherein the inlet stent structure comprises an inlet annulus having struts and the patent stent structure comprises a patent annulus having struts.

36. 36. A stent assembly according to any one of claims 24 to 35, wherein the inlet stent structure comprises a plurality of inlet annuli having struts, and the patent stent structure comprises a plurality of patent annuli having struts.

37. 37. The stent assembly of any one of claims 24 to 36, wherein the inlet stent structure comprises a braided mesh and the patent stent structure comprises a patent annulus having struts.

38. an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force; a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure; a transient pressure zone between the patency zone and the exit zone, the transient pressure zone having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure; 38. The stent assembly of any one of claims 24 to 37, further comprising:

39. the transitional stent structure is connected to a distal portion of the ostial stent structure and a proximal portion of the patent stent structure; 39. The stent assembly of any one of claims 24 to 38, wherein the outlet stent structure is coupled to a distal portion of the patent stent structure and a proximal portion of the outlet stent structure.

40. 40. The stent assembly of any one of claims 24 to 39, wherein the patent zone defines a first patent zone having a first patent stent structure, and the stent assembly further comprises a second patent zone having a second patent stent structure.

41. 41. A stent assembly according to any one of claims 24 to 40, wherein the first patent stent structure has first expansion characteristics and the second patent stent structure has second expansion characteristics.

42. 41. The stent assembly of claim 40, wherein the first patent stent structure has a first patent radial force and the second patent stent structure has a second patent radial force different from the first patent radial force.

43. 42. The stent assembly of claim 41, further comprising an intermediate transition zone having intermediate expansion characteristics different from the first expansion characteristic of the first patent stent structure and the second expansion characteristic of the second patent stent structure, such that the intermediate transition zone is softer than the first patent stent structure and the second patent stent structure.

44. 1. A stent assembly for implantation in a blood vessel, comprising: an entrance zone comprising at least one entrance stent structure, the entrance stent structure being self-expanding and configured to at least substantially conform to the non-circular cross-sectional shape of a portion of the blood vessel in contact with the entrance stent structure when the entrance stent structure expands; a patent zone having at least one patent stent structure configured to self-expand and expand to an expanded shape different from the non-circular cross-sectional shape of the blood vessel, whereby a portion of the blood vessel in contact with the patent stent structure at least substantially conforms to the expanded shape of the patent stent structure, the patent stent structure coupled to an ostial stent structure such that the ostial stent structure is configured to be positioned upstream from a stenosis along the blood vessel and the patent stent structure is configured to be positioned at a compromised point in the lumen; A stent assembly comprising:

45. the inlet stent structure has an inlet radial force; 45. The stent assembly of claim 44, wherein the patent stent structure has a patent radial force greater than the inlet radial force.

46. the ostium stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the blood vessel; 46. ​​The stent assembly of claim 44 or 45, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular shape when expanded into contact with the blood vessel.

47. the inlet radial force of the inlet stent structure is approximately 0.0005 N / mm to 2 N / mm; 47. The stent assembly of any one of claims 44 to 46, wherein the patent radial force of the patent stent structure is approximately 0.001 N / mm to 3 N / mm.

48. 48. A stent assembly according to any one of claims 44 to 47, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to bend to a generally triangular cross-sectional shape when expanded into contact with a blood vessel.

49. 49. A stent assembly according to any one of claims 44 to 48, wherein the inlet stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and is configured to deform to a generally triangular cross-sectional shape when expanded into contact with a generally triangular cross-section of the blood vessel.

50. 50. A stent assembly according to any one of claims 44 to 49, wherein the inlet stent structure has at least a generally triangular cross-sectional shape in an unconstrained expanded state and is configured to conform to the blood vessel when expanded into contact with the blood vessel.

51. 51. A stent assembly according to any one of claims 44 to 50, wherein the patent stent structure has at least a generally circular cross-sectional shape in an unconstrained expanded state and has a generally circular cross-sectional shape when expanded in contact with the blood vessel.

52. 52. The stent assembly of any one of claims 44 to 51, wherein the patent radial force of the patent stent structure is configured to limit constriction of the blood vessel when external pressure on the blood vessel increases.

53. 53. The stent assembly of any one of claims 44 to 52, further comprising an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force.

54. 54. A stent assembly according to any one of claims 44 to 53, further comprising a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure.

55. 55. The stent assembly of any one of claims 44 to 54, further comprising a transient pressure zone adjacent the patency zone and having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure.

56. 56. A stent assembly according to any one of claims 44 to 55, wherein the inlet stent structure comprises an inlet annulus having struts and the patent stent structure comprises a patent annulus having struts.

57. 57. A stent assembly according to any one of claims 44 to 56, wherein the inlet stent structure comprises a plurality of inlet annuli having struts, and the patent stent structure comprises a plurality of patent annuli having struts.

58. 58. The stent assembly of any one of claims 44 to 57, wherein the inlet stent structure comprises a braided mesh and the patent stent structure comprises a patent annulus having struts.

59. an exit zone comprising at least one exit stent structure positioned distal to the patent stent structure, the exit stent structure being self-expanding and having an exit radial force less than the patent radial force; a transition zone between the inlet zone and the patent zone, the transition zone having a transitional stent structure having a transitional radial force greater than the inlet radial force of the inlet stent structure and less than the patent radial force of the patent stent structure; a transient pressure zone associated with the patency zone, the transient pressure zone having a transient stent structure with a transient radial force configured to contract during a physiological spike in cerebrospinal fluid pressure; 59. The stent assembly of any one of claims 44 to 58, further comprising:

60. the transitional stent structure is connected to a distal portion of the ostial stent structure and a proximal portion of the patent stent structure; 60. The stent assembly of any one of claims 44 to 59, wherein the outlet stent structure is coupled to a distal portion of the patent stent structure.

61. 61. A stent assembly according to any one of claims 44 to 60, wherein the patent zone defines a first patent zone having a first patent stent structure, and the stent assembly further comprises a second patent zone having a second patent stent structure.

62. 62. A stent assembly according to any one of claims 44 to 61, wherein the first patent stent structure has first expansion characteristics and the second patent stent structure has second expansion characteristics.

63. 62. The stent assembly of claim 61, wherein the first patent stent structure has a first patent radial force and the second patent stent structure has a second patent radial force different from the first patent radial force.

64. 63. The stent assembly of claim 62, further comprising an intermediate transition zone having intermediate expansion characteristics different from the first expansion characteristic of the first patent stent structure and the second expansion characteristic of the second patent stent structure, such that the intermediate transition zone is softer than the first patent stent structure and the second patent stent structure.

65. 64. The stent assembly of any one of claims 44 to 63, wherein the ostium stent structure and first patent stent structure are configured to be positioned in the superior sagittal sinus and the second patent stent structure is configured to be positioned at least partially in the transverse sinus, and the stent assembly further comprises a transition zone having a transition stent structure with a lower radial force than the first patent stent structure or the second patent stent structure.

66. 1. A method of treating symptoms caused by a stenosis along a dural venous sinus, comprising: (a) positioning the stent assembly in the dural venous sinus such that an entrance zone of the stent assembly is at a location upstream from a point of lumenal compromise in the dural venous sinus relative to blood flow through the dural venous sinus, and (b) a patent zone of the stent assembly is at the stenosed portion of the dural venous sinus; expanding an ostial stent structure in the ostial zone at the upstream location to have a triangular cross-sectional shape that at least substantially approximates a generally triangular cross-sectional shape of the dural venous sinus, the ostial stent structure having an ostial radial force; expanding a patent stent structure in the patent zone at the stenosed portion of the dural venous sinus such that the patent stent structure increases a cross-sectional area of ​​the stenosed portion of the dural venous sinus, the patent stent structure having a patent radial force greater than the inlet radial force; A method comprising:

67. 67. The method of claim 66, wherein the inlet stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and the step of expanding the inlet stent structure includes the step of self-expanding the inlet stent structure so that the inlet stent structure at least substantially approximates the triangular cross-sectional shape of the upstream location.

68. 68. The method of claim 66 or 67, wherein the entrance stent structure is coupled to the patent stent structure before positioning the stent assembly in the dural venous sinus so that a single stent assembly is positioned along the upstream location and the narrowed portion of the dural venous sinus.

69. 69. The method of any one of claims 66 to 68, wherein the symptom is papilledema.

70. 69. The method of any one of claims 66 to 68, wherein the symptom is pulsatile tinnitus.

71. 69. The method of any one of claims 66 to 68, wherein the symptom is a headache.

72. the ostial stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the ostial stent structure includes self-expanding the ostial stent structure such that the ostial stent structure at least substantially approximates the triangular cross-sectional shape of the upstream location; 72. The method of any one of claims 66 to 71, wherein the patent stent structure has a circular cross-sectional shape in an expanded, unconstrained state, and expanding the patent stent structure comprises self-expanding the patent stent structure so that the patent stent structure at least substantially approximates a triangular cross-sectional shape of the narrowed portion of the dural venous sinus.

73. 73. The method of claim 72, wherein, upon expansion, the triangular cross-sectional shape of the ostium stent structure is different from the triangular cross-sectional shape of the patent stent structure.

74. 74. The method of any one of claims 66 to 73, wherein the step of positioning the stent assembly in the dural venous sinus further comprises positioning an exit zone of the stent assembly at a location downstream from the narrowed portion of the dural venous sinus with respect to blood flow through the dural venous sinus, the exit zone having an exit stent structure with an exit radial expansion force greater / less than the patent expansion force.

75. 75. The method of claim 74, further comprising expanding an outlet stent structure of the outlet zone at the downstream location so that the outlet stent structure has a cross-sectional dimension that approximates a cross-sectional dimension at the downstream location.

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