SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a choked flow pipe to in solving current guide tube, adopt the sacculus choked flow and bring the choked flow slow, fail safe nature low, repeatability poor and little scheduling problem of pipe inner chamber.
In order to solve the above technical problem, the utility model provides a choked flow pipe, it includes:
an inner conduit;
the flow blocking element with self-expansion performance is sleeved outside the inner catheter, and at least the near end of the flow blocking element is connected with the periphery of the inner catheter; and
the outer catheter is movably sleeved outside the inner catheter and used for limiting the expansion of the flow resisting element.
Optionally, in the catheter, the flow-impeding element comprises a scaffold, at least a proximal end of the scaffold is connected to an outer circumference of the inner catheter, and the scaffold has self-expansion properties.
Optionally, in the flow-impeding conduit, the flow-impeding element further comprises a flow-impeding membrane, the flow-impeding membrane being attached to the scaffold.
Optionally, in the flow-blocking duct, one end of the flow-blocking element is connected to the outer circumference of the inner duct, and the other end is a free end; or both ends of the flow blocking element are respectively connected with the periphery of the inner guide pipe.
Optionally, in the flow blocking catheter, a groove is formed in the outer periphery of the inner catheter, and the groove is matched with the flow blocking element in shape in a retracted state to accommodate the flow blocking element.
Optionally, the flow blocking conduit further comprises a control valve to drive relative movement between the outer and inner conduits.
Optionally, in the flow blocking catheter, the control valve includes a control valve body and a control slider connected with each other, the control slider is configured to be slidable in the axial direction, the control valve body is connected with the proximal end of the inner catheter, and the control slider is connected with the proximal end of the outer catheter; or the control valve body is connected with the proximal end of the outer catheter, and the control slider is connected with the proximal end of the inner catheter.
Optionally, in the flow blocking duct, the inner duct and/or the outer duct is a single-layer tube made of a polymer material.
Optionally, in the flow blocking conduit, the inner conduit and/or the outer conduit comprises at least a two-layer structure, wherein the first and/or second layer from the inside to the outside is a polymer layer.
Optionally, in the catheter, the inner catheter and/or the outer catheter comprise at least two layers, wherein the second layer from inside to outside comprises one or a combination of two or more of braided structure, coil, and cut hypotube.
Optionally, in the flow blocking conduit, the inner conduit and the outer conduit each comprise a three-layer structure.
Optionally, in the flow blocking catheter, the inner catheter comprises a first visualization ring located at a distal end of the inner catheter.
Optionally, in the flow blocking duct, the inner duct further includes a second developing ring, and the second developing ring is located on the inner duct at a position corresponding to a fixing point of the flow blocking element to the inner duct.
Optionally, in the flow-blocking duct, one end of the flow-blocking element is connected to the outer periphery of the inner duct, and the other end of the flow-blocking element is a free end.
Optionally, in the flow-impeding catheter, the flow-impeding element comprises at least one of a mesh structure, an open loop structure, and a helical structure, the flow-impeding element being made by braiding, winding, or cutting.
Optionally, in the flow-blocking catheter, the mesh structure is woven by 1 to 64 wires, the wires are selected from at least one of a plain wire, a developing wire and a composite wire, the plain wire is selected from at least one of a nickel-titanium alloy, a cobalt-chromium alloy, stainless steel and a polymer, the developing wire is selected from a developing metal, an alloy of a developing metal or a polymer material added with a developer, and the composite wire is formed by compounding a developing core wire and the plain wire.
Optionally, the flow-impeding catheter further comprises a fixation membrane fixedly attached to an exterior of the proximal end of the flow-impeding element and at least partially covering the flow-impeding element and a portion of the inner catheter.
To sum up, the utility model provides a choked flow pipe includes inner catheter, choked flow component and outer catheter, choked flow component have from expanding nature, its cover is located the outside of inner catheter, and choked flow component's at least near-end with the periphery of inner catheter is connected; the outer catheter is movably sleeved outside the inner catheter and used for limiting expansion of the flow resisting element. By the configuration, the expansion of the flow resisting element can be controlled by controlling the advance and retreat of the outer catheter or the inner catheter, the configuration conversion time is short, the positioning can be repeated in the operation process, and the operation is simple, convenient and time-saving; in addition, the flow resisting element blocks the blood flow through the expansion with controllable amplitude, so that the stimulation to the cerebral vessel wall is low, and the problem of easy rupture caused by the adoption of a balloon can be avoided; in addition, when the flow resisting element contracts, the thickness of the flow resisting element is thinner, so that the inner diameter of the flow resisting element can be increased on the premise of controlling the outer diameter of the flow resisting catheter, and the flow resisting catheter is suitable for larger thrombus or instruments.
Detailed Description
To make the objects, advantages and features of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments. It is to be noted that the drawings are in simplified form and are not to scale, but rather are provided for the purpose of facilitating and distinctly claiming the embodiments of the present invention. Further, the structures illustrated in the drawings are often part of actual structures. In particular, the drawings may have different emphasis points and may sometimes be scaled differently.
As used in this specification, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise, the term "proximal" generally being the end near the operator and the term "distal" generally being the end near the lesion in the patient. As used in this specification, "one end" and "the other end" and "proximal end" and "distal end" generally refer to the corresponding two parts, which include not only the end points.
The core idea of the utility model is to provide a choked flow pipe to in solving current guide tube, adopt the sacculus choked flow and bring the choked flow slow, fail safe nature low, repeatability poor and little scheduling problem of pipe inner chamber. The flow-blocking catheter includes: the flow blocking element has self-expansion performance, is sleeved outside the inner catheter, and at least the near end of the flow blocking element is connected with the periphery of the inner catheter; the outer catheter is movably sleeved outside the inner catheter and used for limiting expansion of the flow resisting element. By the configuration, the expansion of the flow resisting element can be controlled by controlling the advance and retreat of the outer catheter or the inner catheter, the configuration conversion time is short, the blood circulation of tissues is hardly influenced, the positioning can be repeated in the operation process, and the operation is simple, convenient and time-saving; in addition, the flow resisting element blocks the blood flow through the expansion with controllable amplitude, so that the stimulation to the cerebral vessel wall is low, and the problem of easy rupture caused by the adoption of a balloon can be avoided; in addition, when the flow resisting element contracts, the thickness of the flow resisting element is thinner, so that the inner diameter of the flow resisting element can be increased on the premise of controlling the outer diameter of the flow resisting catheter, and the flow resisting catheter is suitable for larger thrombus or instruments.
The following description refers to the accompanying drawings.
Referring to fig. 1 to 10g, wherein, fig. 1 is a schematic view of a choke catheter provided in a preferred embodiment of the present invention, fig. 2 is a schematic view of a cross section of an inner catheter provided in a preferred embodiment of the present invention, fig. 3 is a schematic view of a choke element provided in a preferred embodiment of the present invention after expansion, fig. 4 is a schematic view of a control valve provided in a preferred embodiment of the present invention, fig. 5 is a schematic view of a cross section of a choke catheter provided in a preferred embodiment of the present invention, fig. 6 is a schematic view of a choke catheter provided with a groove according to a preferred embodiment of the present invention, fig. 7 is a schematic view of a choke catheter provided with a fixed film according to a preferred embodiment of the present invention, fig. 8 is a schematic view of fixedly connecting both ends of a choke element respectively with an inner catheter provided in a preferred embodiment of the present invention, fig. 9 is a schematic view of a braided structure of a choke element provided in a preferred embodiment of the present invention, fig. 10a to 10g are schematic views of meshes of a support frame according to a preferred embodiment of the present invention.
As shown in fig. 1 and 2, the first embodiment provides a flow blocking catheter, which includes: aninner catheter 100, a flow-impedingelement 300, and anouter catheter 200; the flow-blockingelement 300 has self-expanding properties, the flow-blockingelement 300 is sleeved outside theinner catheter 100, and at least the proximal end (the first end 310) of the flow-blockingelement 300 is connected to the outer circumference of the inner catheter 100 (e.g., by gluing, welding, or using a fixing film). Theouter catheter 200 is movably sleeved outside theinner catheter 100 to limit the expansion of theflow blocking element 300. In some embodiments, the flow-blockingelement 300 is configured such that, when theouter catheter 200 is moved in the proximal direction of theinner catheter 100, the flow-blockingelement 300 is released from its restriction, and the flow-blockingelement 300 expands (meaning expands radially) due to its self-expanding characteristic; theouter catheter 200 is moved toward the distal end of theinner catheter 100, so that the expansion of theflow blocking element 300 is restricted, and theflow blocking element 300 is contracted (i.e., restored by contraction in the radial direction). In other embodiments, the expansion and contraction of the flow-impedingelement 300 may also be controlled by movement of theinner catheter 100 relative to theouter catheter 200. In this embodiment, thefirst end 310 of the flow-obstructingelement 300 is disposed near the distal end of theinner catheter 100 to bring the flow-obstructing location closer to the location of the embolectomy or other instrument operation, reducing the effect on the proximal vascular blood flow, and in other embodiments, thefirst end 310 of the flow-obstructingelement 300 may be disposed in the middle or near the proximal end of theinner catheter 100.
In an exemplary embodiment, theinner catheter 100 and theouter catheter 200 are preferably circular tubes, theouter catheter 200 is sleeved outside theinner catheter 100, the difference between the inner diameter of theouter catheter 200 and the outer diameter of theinner catheter 100 can be 0.0001-0.1 inches, and theouter catheter 200 is preferably a single-layer tube made of one or more materials selected from the group consisting of polyether polyamide block copolymer (PEBA or Pebax), Polyamide (PA), and Polytetrafluoroethylene (PTFE). Theinner catheter 100 comprises at least one single polymer layer of a polymer material selected from one or more of Polytetrafluoroethylene (PTFE), High Density Polyethylene (HDPE), Pebax mixed with a coefficient of friction reducing additive, and polyolefin elastomer (POE). Theinner catheter 100 preferably comprises a three-layer structure, as shown in fig. 5, of afirst layer 101, asecond layer 102, and athird layer 103, respectively, from the inside out. Wherein, the material of thethird layer 103 may be one or more of nylon elastomer (such as Pebax), nylon and Polyurethane (PU); the material of thefirst layer 101 may be one or more of Polytetrafluoroethylene (PTFE), High Density Polyethylene (HDPE), Pebax mixed with a friction coefficient reducing additive, and polyolefin elastomer (POE); thesecond layer 102 is one or a combination of two or more of a braided structure, a coil and a cut hypotube (hypotube generally refers to a medical metal tube), and the material of thesecond layer 102 may be stainless steel, nickel-titanium alloy, cobalt-chromium alloy or polymer filament. To improve the mechanical transmission properties and the anti-ovality and anti-buckling capabilities of theinner catheter 100 and to reduce the force required for theresistive element 300 recovery. It should be understood that the materials of the various layers of theinner catheter 100 are not limited to the above materials, and those skilled in the art can select other materials with similar properties according to the prior art. In an alternative embodiment, as shown in fig. 2, theinner catheter 100 comprises only two layers, from inside to outside, afirst layer 101 and asecond layer 102, wherein thefirst layer 101 is mainly a polymer layer and is made of one or more of Polytetrafluoroethylene (PTFE), High Density Polyethylene (HDPE), Pebax mixed with a friction-reducing additive, and polyolefin elastomer (POE), thesecond layer 102 is mainly a metal layer, such as one or more of a woven structure, a coil, and a cut hypotube, and thesecond layer 102 is made of stainless steel, nitinol, or cobalt-chromium alloy. Preferably, a layer ofadhesive 104 is disposed outside the polymer layer, and the adhesive 104 penetrates the metal layer (i.e., part of the adhesive 104 penetrates the meshes of the metal layer and is adhered to the outside of the metal layer), so that the metal layer and the polymer layer are firmly embedded to improve the conductive performance and the anti-elliptical capability. Of course, in other embodiments, theouter conduit 200 is not limited to a single-layer tube, and theouter conduit 200 may also include a two-layer structure, a three-layer structure, or a more-layer structure, and the specific structural configuration thereof may refer to theinner conduit 100.
Preferably, theinner catheter 100 includes afirst visualization ring 120, thefirst visualization ring 120 being located at the distal end of theinner catheter 100. Specifically, thefirst visualization ring 120 may be disposed at the distal end of thesecond layer 102 of theinner catheter 100. More preferably, theinner catheter 100 further comprises a second visualization ring (not shown) located at a position of theinner catheter 100 corresponding to the fixation point of the flow-obstructingelement 300 to theinner catheter 100. Further, when one end of theflow blocking element 300 is connected to the outer circumference of theinner guide tube 100 and the other end is a free end, theflow blocking element 300 further includes a third developing ring (not shown) at the free end of theflow blocking element 300, and the third developing ring is disposed to visually reflect the expanded state of the free end of theflow blocking element 300. Alternatively, the first developingring 120, the second developing ring and the third developing ring may be made of, but not limited to, platinum, iridium, tantalum, noble metal alloy, etc., or may be made of a polymer material containing a developer. The three visualization rings are provided to facilitate the operator to position theinner catheter 100 or to visually reflect the expanded state of theflow blocking element 300 during the operation. It should be understood that thefirst visualization ring 120 is located at the distal end of theinner catheter 100, and thefirst visualization ring 120 is not limited to being located at the distal end of theinner catheter 100, but may be located in an area near the distal end of theinner catheter 100. Further, the above examples merely exemplify the arrangement positions of the developing rings, and do not limit that the three developing rings are necessarily arranged at the same time, and any one or any two of the developing rings may be selectively arranged by those skilled in the art according to the actual situation.
Preferably, theflow blocking element 300 comprises a scaffold, at least the proximal end of which is connected to the outer circumference of theinner catheter 100, and a flow blocking membrane, and optionally, theflow blocking element 300 further comprises a flow blocking membrane, which is attached to the scaffold. In one example, the scaffold is a tubular body that is capable of being transitioned between a retracted state and an expanded state under the constraints of theouter catheter 200, it being understood that the scaffold is not limited to being switchable only between the retracted state and the expanded state, and in some cases, may be in an intermediate state between the retracted state and the expanded state (i.e., a semi-expanded state or a partially expanded state). The material of the support frame can be nickel-titanium alloy, 304 stainless steel, platinum-tungsten alloy, platinum-iridium alloy, cobalt-chromium alloy or developed metal, and the structure of the support frame can be obtained by winding, cutting or weaving. In this embodiment, the supporting frame comprises a plurality of mesh holes 340, and as shown in fig. 10a to 10g, the mesh holes 340 may be diamond-shaped (fig. 10a), square-shaped (fig. 10b), rectangular-shaped (fig. 10c), parallelogram-shaped (fig. 10d), polygonal-shaped (not shown), circular-shaped (fig. 10e), oval-shaped (fig. 10f), irregular-shaped (fig. 10g), and the like, and preferably diamond-shaped (fig. 10 a). The flow-blocking film can be attached to the inner surface or the outer surface of the support frame, and is preferably a polymer film, and the material of the flow-blocking film can be Polyurethane (PU), Polyethylene (PE), Expanded Polytetrafluoroethylene (EPTFE) or the like. It is to be understood that the material of the supporting frame and the flow-resisting film is not limited to the above materials, and those skilled in the art can select other materials with similar performance according to the prior art. As shown in fig. 9, in some embodiments, the supporting frame may have a mesh structure, and is woven by 1 to 64 wires, wherein the wires are selected from at least one of common wires, developing wires and composite wires, and the common wires may be selected from one or more of nickel-titanium alloy, cobalt-nickel alloy, stainless steel, polymer, and the like; the developing wire can be made of developing metals such as platinum, iridium, gold, tungsten and the like or alloys thereof, or can be made of polymer wires added with developers, and the developers are the developing metals or the developing alloys; the composite wire is made by compounding a developing core wire and a common wire and has a double-layer structure, wherein the developing core wire at the inner layer is made of one or more developing metals such as platinum, iridium, gold or tungsten or alloys thereof, and the common wire at the outer layer is made of one or more materials such as nickel-titanium alloy, cobalt-nickel alloy, stainless steel, high polymer and the like. The developingwire 330 improves the developing performance of theflow blocking element 300 and improves the trackability of theflow blocking element 300 in use. In other embodiments, the scaffold may also be an open-loop structure or a helical structure, or the scaffold may be composed of several of a lattice structure, an open-loop structure and a helical structure.
Referring to fig. 1 and 3, theouter catheter 200 may control the expansion of the flow-blockingelement 300 when moving along the axial direction of the inner catheter 100 (the expansion of the flow-blockingelement 300 may be understood to be the same as the expansion of the scaffold). Specifically, in the initial default state of the flow-blocking catheter, the outer catheterdistal end 210 overlies the flow-blockingelement 300, limiting expansion of the flow-blockingelement 300, such that the flow-blockingelement 300 is in a retracted state and is crimped between theinner catheter 100 and theouter catheter 200, facilitating transport of the flow-blocking catheter in the blood vessel. When theouter catheter 200 is moved proximally relative to the inner catheter 100 (i.e., theouter catheter 200 is withdrawn), the flow-blockingelement 300 is exposed from theouter catheter 200, and the flow-blockingelement 300 self-expands to adhere to the blood vessel wall, thereby blocking blood flow due to the attachment of a flow-blocking membrane to the scaffold of the flow-blockingelement 300. It is to be understood that the expanded configuration of the obstructingelement 300 is now adapted to the vessel wall and is not necessarily in a fully expanded state (i.e. possibly in a semi-expanded state). In other cases, of course, when theouter catheter 200 is withdrawn, thedistal end 210 of the outer catheter may not leave the flow-blockingelement 300, such that a portion of the flow-blockingelement 300 is no longer constrained by theouter catheter 200, and therefore, the portion of the flow-blockingelement 300 may naturally expand and conform to the blood vessel wall, thereby blocking blood flow, i.e., theouter catheter 200 may release a portion of the flow-blockingelement 300, rather than having to release all of the flow-blocking element 300 (i.e., the flow-blockingelement 300 may be in a partially expanded state). The flow-impedingelement 300 preferably has a certain compliance that can adapt to the morphology of the vessel wall in the expanded state (including the fully expanded state, the semi-expanded state, or the partially expanded state). So configured, some relatively weak vessel walls may be accommodated, which may reduce the pressure on the vessel wall caused by the expansion of theresistive element 300. Therefore, theflow blocking element 300 can reduce the stimulation to the cerebral vessel wall, reduce the occurrence of various complications such as vasospasm and the like in the operation process, and simultaneously thoroughly avoid the risk of secondary damage to the vessel caused by the rupture of the balloon or the balloon bonding section.
Further, after the blood flow is blocked, suction or thrombus retraction can be directly performed through the lumen of the inner catheter 100 (the lumen of theinner catheter 100 of the flow blocking catheter can also be passed through a suction catheter or a support catheter, suction of thrombus can be performed through the suction catheter, or thrombus removal can be performed through a thrombus removal stent in the support catheter). As shown in fig. 2, since the thickness of theflow blocking element 300 is smaller when in the retracted state, the ratio of the inner cavity of theinner catheter 100 in the cross section of the whole flow blocking catheter is much larger than that of the existing balloon flow blocking catheter, so that the flow blocking catheter with the same outer diameter can be adapted to medical devices such as a suction catheter, a support catheter or a stent with a larger lumen, and is suitable for treating larger thrombus, and simultaneously, the outer diameter of the whole flow blocking catheter is limited to smoothly enter a tortuous distal end blood vessel and form a smaller wound for a patient.
Further, when it is desired to change the flow-blocking position to reposition or remove the flow-blocking catheter, theouter catheter 200 may be operated to move proximally relative to the inner catheter 100 (i.e., to withdraw the outer catheter 200) until the distal end of theouter catheter 200 abuts against the flow-blockingelement 300, as shown in fig. 3. And continues to push theouter catheter 200 distally until the flow-obstructingelement 300 is constrained to the collapsed state. On the basis of fig. 3, when theouter catheter 200 is withdrawn proximally, the state of the flow-blockingelement 300 is reversible, i.e. the flow-blockingelement 300 may expand again by itself. The repeatable contractibility of the flow-impedingelement 300 facilitates the re-delivery positioning of the flow-impeding conduit. Therefore, the flow blocking catheter provided by the embodiment can conveniently realize repeated operation and accurate positioning, and can also conveniently withdraw the blood vessel after thrombus removal.
As shown in fig. 4, the flow blocking conduit further comprises acontrol valve 400, thecontrol valve 400 being configured to drive theouter conduit 200 to move relative to theinner conduit 100. In one embodiment, thecontrol valve 400 includes acontrol valve body 410 and acontrol slider 420, wherein thecontrol valve body 410 is provided with a slidinggroove 430 along an axial direction, and thecontrol slider 420 is matched with the slidinggroove 430 and can slide along the direction of the slidinggroove 430. Further, one end of thecontrol valve body 410 has acatheter insertion opening 440, and the proximal end of theinner catheter 100 is inserted into thecontrol valve 400 through thecatheter insertion opening 440 and fixedly connected to thecontrol valve body 410, while the proximal end of theouter catheter 200 is connected to thecontrol slider 420, for example, by gluing or snapping. With such a configuration, the sliding of theslider 420 is controlled to control the movement (e.g., withdrawing or pushing) of theouter catheter 200 relative to theinner catheter 100, and thecontrol valve 400 controls the expansion or retraction state of theflow blocking element 300, so as to simplify the operation, save the operation time, and conveniently realize the repetitive operation. Optionally, the proximal end of theouter catheter 200 includes a diffusion stressedtube 220, and the diffusion stressedtube 220 may be flared towards the proximal end, i.e. the distal end of the diffusion stressedtube 220 has the same diameter as theouter catheter 200, while the proximal end of the diffusion stressedtube 220 has a larger diameter than theouter catheter 200. With this configuration, the diameter of the portion of theouter guide pipe 200 for connection with thecontrol slider 420 is increased, and the flareddiffusive stress pipe 220 disperses the driving force of thecontrol slider 420 to theouter guide pipe 200, thereby improving the reliability of control of theouter guide pipe 200 by thecontrol slider 420. In other embodiments, the outer conduit may be connected to thecontrol valve body 410, theinner conduit 100 may be connected to thecontrol slider 420, or other direct or indirect connection methods may be adopted, which is not limited in the present invention.
Referring to fig. 6, in a preferred embodiment, theinner catheter 100 is provided with agroove 110 at the periphery, and thegroove 110 matches with the shape of theflow blocking element 300 in the retracted state to accommodate theflow blocking element 300. Wherein said matching of shapes includes the case where the size of therecess 110 is the same as the size of the obstructingelement 300 in the retracted state and the size of therecess 110 is larger than the size of the obstructingelement 300 in the retracted state. Alternatively, therecess 110 is an annular recess around theinner catheter 100, and the obstructingelement 300 may be embedded in therecess 110 when the obstructingelement 300 is in the fully retracted state. Preferably, the length of therecess 110 is greater than or equal to the length of the obstructingelement 300 in the retracted state, so that the obstructingelement 300 can be completely accommodated in therecess 110. The provision of thegrooves 110 allows the gap between theouter catheter 200 and theinner catheter 100 to be smaller, thereby further reducing the proportion of catheter in the cross-section of the entire flow-obstructing catheter and increasing the proportion of lumen of theinner catheter 100. The provision of thegrooves 110 may maintain a uniform outer diameter throughout the catheter, preventing the flow-impedingelement 300 from being damaged when the catheter passes through a tortuous blood vessel during transport in the blood vessel. Furthermore, the radial distances of the fixed points of the flow-obstructingelement 300 and theinner catheter 100 relative to the axial direction of theinner catheter 100 are substantially equal, which facilitates the concentricity of the flow-obstructingelement 300 without eccentricity when expanding, increases the adherence uniformity of the flow-obstructingelement 300, and thus reduces the risk of leakage.
Referring to fig. 3, in a preferred embodiment, one end of the flow-resistingelement 300 is connected to the outer circumference of theinner catheter 100, for example, by gluing or welding, and the other end of the flow-resistingelement 300 is a free end. Optionally, the first end 310 (e.g., proximal end) of the flow-blockingelement 300 is attached to the outer surface of theinner catheter 100, and the second end 320 (e.g., distal end) is free, such that when the flow-blockingelement 300 is in the expanded state, thesecond end 320 is spaced from the distal end of theinner catheter 100 by a distance of 0-500mm, it being understood that thesecond end 320 does not extend beyond the distal end of theinner catheter 100, i.e., the flow-blockingelement 300 is positioned closer to the operator than the distal end of theinner catheter 100.
As shown in fig. 7, the catheter may further include a fixingfilm 500, and the fixingfilm 500 may be attached to the outer portion of the proximal end of theflow blocking element 300, at least partially covering theflow blocking element 300 and partially covering theinner catheter 100. The fixing means of the fixingfilm 500 to theflow blocking element 300 and theinner catheter 100 may be gluing, heat shrinking, or the like, and the fixing capability between theflow blocking element 300 and theinner catheter 100 may be enhanced by the fixingfilm 500. Optionally, thefixation membrane 500 has an axial length between 1mm and 10 mm. It should be noted that, in some embodiments, the flow-resistingelement 300 may be first fixed (e.g., bonded or welded) to theinner catheter 100, and then the fixingfilm 500 may be used as a second reinforcing fixing, further reinforcing the reliability of the fixing; in other embodiments, the flow-resistingelement 300 and theinner catheter 100 may be fixed by the fixingfilm 500 only by a size fit or an interference fit, which is not limited by the present invention.
Referring to fig. 8, in another preferred embodiment, both ends of the flow-obstructingelement 300 are respectively connected to the outer circumference of theinner catheter 100, for example, by gluing, welding or using a fixing film. Optionally, the two ends of theflow blocking element 300 are spaced at a certain distance, so configured, when theflow blocking element 300 is in the expanded state, theflow blocking element 300 is in a shuttle shape, which can better fit the blood vessel wall to achieve the effect of blocking the blood flow, and in addition, under the impact of the blood flow, the form of theflow blocking element 300 is more stable, and the risk of leakage can be further reduced. Of course, in some other embodiments, the two ends of theflow blocking element 300 may be disposed adjacent to each other or overlapped with each other, and the expansion state of the correspondingflow blocking element 300 may be an Ω shape, which may also achieve better effect, therefore, the present invention does not limit the distance between the two ends of theflow blocking element 300.
To sum up, the utility model provides a choked flow pipe includes inner catheter, choked flow component and outer catheter, choked flow component have from expanding nature, its cover is located the outside of inner catheter, and choked flow component's at least near-end with the periphery of inner catheter is connected; the outer catheter is movably sleeved outside the inner catheter and used for limiting expansion of the flow resisting element. By the configuration, the expansion of the flow resisting element can be controlled by controlling the advance and retreat of the outer catheter or the inner catheter, the configuration conversion time is short, the positioning can be repeated in the operation process, and the operation is simple, convenient and time-saving; in addition, the flow resisting element blocks the blood flow through the expansion with controllable amplitude, so that the stimulation to the cerebral vessel wall is low, and the problem of easy rupture caused by the adoption of a balloon can be avoided; in addition, when the flow resisting element contracts, the thickness of the flow resisting element is thinner, so that the inner diameter of the flow resisting element can be increased on the premise of controlling the outer diameter of the flow resisting catheter, and the flow resisting catheter is suitable for larger thrombus or instruments.
The above description is only for the preferred embodiment of the present invention and is not intended to limit the scope of the present invention, and any modification and modification made by those skilled in the art according to the above disclosure are all within the scope of the claims.