Device for manipulating catheters

Abstract

A system includes: an outer member, an elongated cylindrical member extending distally from the outer member, and an inner member positioned coaxially with and attached to the cylindrical member. The inner member extends distally to the outer member and has a distal portion. A conduit is positioned within the outer conduit (e.g., a suction conduit), which provides a reinforcing member on the cylindrical member to restrict movement of the cylindrical member, such that when one of the inner or outer members moves relative to the other, axial compression of the cylindrical member is restricted by the inner wall of the outer conduit, resulting in lateral deflection of the distal portion of the inner member, thereby changing the direction of the outer conduit.

Description

[0001] This application claims priority to provisional application 63 / 111,122, filed on November 9, 2020. Technical Field

[0002] This application relates to medical devices, and more specifically, to medical devices for manipulating catheters to help traverse tortuous paths. Background Technology

[0003] The necessity of manipulating catheters through tortuous paths is widely recognized. Several methods exist to achieve this manipulation.

[0004] A coaxial conduit disclosed by the same inventors as this application in U.S. Patent No. 9,233,225 (hereinafter referred to as '225 Patent) provides a deflectable conduit having a deflection mechanism in the form of a cylindrical member for deflecting the conduit. The cylindrical member is attached at one end to an inner conduit and at the other end to an outer conduit. A reinforcing tube is placed on the cylindrical member to restrict axial movement of the cylindrical member such that when one of the inner or outer conduits is moved relative to the other, axial compression of the cylindrical member is restricted by the reinforcing member, thereby causing the distal portion of the inner conduit to deflect laterally.

[0005] While the catheter of the '225 patent advantageously achieves deflection in a low-profile, less complex, and consistent manner, further reduction in profile may be beneficial in certain applications. In some applications, designing a cylindrical member to allow its use with a variety of catheters may also be advantageous.

[0006] Current catheters also have difficulty navigating complex anatomical structures, such as those of the neurovascular system. This is due to the size difference between certain catheters (e.g., aspiration catheters) and smaller diameter guidewires or smaller diameter catheters into which they are inserted. These catheters often get stuck at the junction of blood vessels (a phenomenon known as the vessel wall effect) and / or the shoulder between the catheter and the inner guidewire or internal catheter may damage the vessel wall and potentially lead to dissection and subarachnoid hemorrhage.

[0007] It would be advantageous to provide a system that improves the navigation of catheters through tortuous vascular systems and avoids the possibility of them getting stuck at vascular junctions or causing trauma to the vessels. Such a system for certain applications would advantageously have a reduced profile to facilitate the passage of blood clots. Summary of the Invention

[0008] This invention provides a bidirectional deflectable device that offers a low (reduced) profile and can be used with a variety of catheters. Therefore, the device of this invention can be inserted into standard catheters or uniquely designed catheters and actuated to deflect such catheters, which can be achieved without altering the catheter structure.

[0009] The coaxial bidirectional deflectable device / system of the present invention helps navigate in tortuous vascular systems and reduces the likelihood of the catheter getting stuck at vascular junctions during insertion, and reduces the chance of trauma, such as the risk of vascular dislodgement or bleeding during insertion / navigation.

[0010] In one aspect, the present invention provides a deflectable device (e.g., a deflectable conduit) that is placed inside another separate external conduit and uses the device's deflection mechanism (i.e., a columnar member) to deflect the external conduit.

[0011] In another aspect, the present invention provides a system comprising a first device having: an outer member having a proximal portion and a distal portion; an inner member coaxially positioned within the outer member and extending distally to the outer member and having a distal portion; and an elongated cylindrical member attached to the inner member and extending externally to the inner member. The first device is slidably positioned within the lumen of an outer conduit such that the cylindrical member is positioned within the lumen of the outer conduit, wherein, when one of the inner member or the outer member moves relative to the other, axial compression of the cylindrical member is limited by the inner wall of the outer conduit, thereby causing a lateral deflection of the distal portion of the inner member to reorient (redirect) the outer conduit.

[0012] In some embodiments, the internal member has a central longitudinal axis, and the column member is radially offset relative to the central longitudinal axis.

[0013] In some embodiments, the external catheter is a suction catheter.

[0014] In some embodiments, the cross-section of the column member is non-circular.

[0015] In some embodiments, a marking strip is positioned on the internal member, and the columnar member is attached to the marking strip.

[0016] In some embodiments, the column member is attached to an external member at its proximal end and to an internal member at its distal end.

[0017] In some embodiments, the column member has a distal end adjacent to a softer distal segment of the inner member, and the inner member extends from the distal end of the column member by approximately 2 cm.

[0018] In some embodiments, a reinforcing member is positioned on the columnar member, which contacts the inner wall of the second conduit during deflection.

[0019] In some embodiments, the columnar member contacts the inner wall of the external conduit during deflection.

[0020] According to another aspect of the invention, a system is provided comprising: a) an outer member having a proximal portion and a distal portion; b) an inner member coaxially positioned within the outer member, the inner member extending distally toward the outer member and having a distal portion and a distal edge; and c) an elongated columnar member attached to the inner member and extending externally thereto. The columnar member is attached to the outer member at a first end and to the inner member at a second end. The second end of the columnar member is positioned proximal to the distal edge of the inner member, leaving an elongated extension of the inner member extending distally toward the columnar member. When the columnar member is constrained by an external structure, and one of the inner or outer members moves relative to the other, the distal portion of the inner member deflects laterally.

[0021] The column-shaped member preferably terminates at the distal end of the softer distal section adjacent to the internal member.

[0022] In some embodiments, lateral deflection is achieved when the columnar member is constrained by the inner wall of an external conduit in which the columnar member is positioned.

[0023] In some embodiments, a marking band is positioned on an inner member spaced proximally from the farthest edge or elongated portion, and a columnar member is attached to the marking band.

[0024] According to another aspect of the present invention, a method for guiding a catheter through a vascular system is provided, comprising:

[0025] a) Inserting a first device into an external conduit, the first device having an internal member, an external member, and a columnar member connected to the internal member and / or the external member;

[0026] b) When the columnar member is bent within the lumen of the external conduit, one of the internal or external members moves relative to the other to achieve axial compression of the columnar member. The inner wall restricts the movement of the columnar member, causing the distal portion of the internal member to deflect laterally; and

[0027] c) Advance the external catheter on the distal portion of the deflection to change its direction.

[0028] The external conduit can be advanced independently on the device, or it can be advanced as a unit with the device.

[0029] In some embodiments, the columnar member is deflected to contact the inner wall of the external conduit and to provide anchorage for the first device.

[0030] In some embodiments, the external catheter is a suction catheter.

[0031] In some embodiments, the distal portion of the first device is manipulated via a columnar member to change the direction of the external catheter away from the ophthalmic artery junction.

[0032] In some embodiments, the method further includes the step of moving the columnar member to stabilize the exposed section of the internal member.

[0033] In some embodiments, the method further includes advancing a portion of the internal member extending distal to the columnar member through a blood clot in a blood vessel. In some embodiments, the method further includes passing a stent retrieval device or other clot removal device through the internal member after partially passing the internal member through the blood clot. Attached Figure Description

[0034] This document describes preferred embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0035] Figure 1 It is a side view of a prior art deflectable catheter disclosed in U.S. Patent No. 9,233,225;

[0036] Figure 2 yes Figure 1 A side view of the external conduit of the prior art, which shows a columnar member extending from it;

[0037] Figure 3 It is located inside an external catheter to form a deflectable catheter. Figure 1 Side view of the internal conduit of the prior art (the reinforcing tube has been removed for clarity);

[0038] Figure 4 yes Figure 3 An enlarged view of the distal portion of the deflectable conduit, with the lateral reinforcement (support) tube removed to show the column;

[0039] Figure 5 It has a transverse reinforcing tube. Figure 4 Enlarged view of the distal portion of the deflectable catheter;

[0040] Figure 6 This is a side view of the distal region of a deflectable device for deflecting an external catheter according to an embodiment of the present invention;

[0041] Figure 7 This is a side view of the distal region of an alternative embodiment of the deflectable device of the present invention, which has a lateral support tube;

[0042] Figure 8 This illustrates what happens when the inner member is pulled proximally relative to the outer member. Figure 6 The deflection of the device;

[0043] Figure 9 This illustrates what happens when the inner member is moved distally relative to the outer member. Figure 6 The deflection of the catheter;

[0044] Figure 10 It is inserted into the suction cannula. Figure 6 A side view of the device;

[0045] Figure 11 It shows Figure 10 The device and the deflection of the suction catheter, wherein the suction catheter acts as a support tube for deflection;

[0046] Figure 12A It is a perspective view showing how the aspiration catheter gets stuck at the junction of the ophthalmic artery and the neurovascular system;

[0047] Figure 12B It is similar to Figure 12A The view shows an aspiration catheter guided by a smaller distal access catheter;

[0048] Figure 12C and Figure 12D The present invention is shown Figure 6 The device is used to deflect the aspiration catheter within the neurovascular system; and

[0049] Figures 13A-13F It shows Figure 6 The use of the device in the process of removing blood clots, wherein:

[0050] Figure 13A The diagram shows the use of a guide wire to pass through the clot;

[0051] Figure 13B The distal end of the device is shown being moved distally to pass through the clot;

[0052] Figure 13C The device is shown in its proper position after the guidewire has been removed;

[0053] Figure 13D The deployment of the support retrieval device through the internal components is shown;

[0054] Figure 13E Aspiration via an external catheter is shown; and

[0055] Figure 13F The image shows the stent retrieval device moving proximally to remove the clot. Detailed Implementation

[0056] This invention provides a bidirectional deflectable device (catheter) with enhanced deflection to achieve and facilitate distal deflection in narrow and tortuous vascular systems. The device has a deflectable distal portion that is deflected due to the arrangement of an internal member, an external member, and a columnar member. The columnar member is attached to the internal and external members. The device is insertable into an external catheter (e.g., an aspiration catheter, intermediate catheter, or other catheter), such that the columnar member of the device is located within the lumen of the external catheter, such that the inner wall of the lumen of the external catheter provides a movement-restricting member for the columnar member. Because this restricting member (provided by the external catheter) limits axial movement of the column, the relative movement of the external and internal members results in lateral deflection of the distal portion of the device. This will be explained in more detail below.

[0057] In the device of the present invention, the distal ends of the columnar member and the inner member are spaced proximally by a sufficiently large distance. This results in a lower profile, enabling passage, for example, through clumps. This will also be described in more detail below.

[0058] A deflectable conduit is disclosed in U.S. Patent 9,233,225 by the same inventors as this application. This deflectable conduit has a deflection mechanism in the form of a cylindrical member for deflecting the conduit. The cylindrical member is attached at one end to an inner conduit (member) and at the other end to an outer conduit (member). A reinforcing tube is placed on the cylindrical member to restrict axial movement of the cylindrical member such that when one of the inner or outer conduits moves relative to the other, the axial compression of the cylindrical member is restricted by the reinforcing member, thereby causing the distal portion of the inner conduit to deflect laterally.

[0059] While the catheter of the '225 patent advantageously achieves deflection in a low-profile, less complex, and consistent manner, further reduction in profile may be beneficial in certain applications, such as for traversing the clot. In some applications, it may also be beneficial to design a columnar member that allows it to be used with a variety of catheters, i.e., the limiting member is not "built-in" into the device.

[0060] Marked as "Prior Art" Figure 1-5 Features of the catheter from patent '225 are shown to aid in understanding the invention. It will first be described... Figure 1-5 Then, the apparatus of the present invention will be discussed in detail. It should be understood that the following discussion... Figure 1-5 The discussion provided provides an overview, and further details can be found in U.S. Patent No. 9,233,225 (hereinafter referred to as '225 Patent), the entire contents of which are incorporated herein by reference.

[0061] exist Figure 1-5 In this system, the movement-limiting (reinforcing) component is part of the catheter (built into the catheter) to allow for the deflection of the catheter. Figure 6-11 In this invention, the movement restriction (reinforcement) member is provided by a separate external conduit, in which the device of the invention is disposed, and the device of the invention is used to deflect the external conduit.

[0062] Go to Figure 1 This illustrates a bidirectional coaxial deflectable microcatheter according to prior art patent '225. Catheter 10 includes an inner catheter (component) 12, an outer catheter (component) 24, and a distal portion 48 having a deflectable end.

[0063] The internal catheter 12 extends between the proximal end 16 and the distal end 58, and the diameter of its internal lumen is in the range of about 0.001” to about 1.993”, preferably with an inner diameter of about 0.017”. The proximal end of the internal catheter body 14 is connected to a hub 20 resting on a stress relief member 22. The hub 20 may also be fitted with a rotary hemostatic valve (RHV) 18 to provide access to the internal lumen of the internal catheter 12 for inserting accessories or introducing fluid through the side arm.

[0064] The internal catheter 12 includes a catheter body 14 having a rigid proximal section composed of a braided, reinforced polymer tube extending between a proximal end 16 and a distal end 58. This proximal section is coupled distally to a less rigid distal tube. The internal catheter body 14 also includes a laser-cut tube 76. Figure 4 The laser cutting tube 76 is connected to the distal tube at its distal end.

[0065] One embodiment has a lubricated inner liner extending from the proximal end to the distal end to help reduce the coefficient of friction, thereby facilitating the movement of the guidewire within the internal conduit.

[0066] Patent '225 discloses several embodiments of the internal conduit. In these embodiments, the columnar member extends almost to the end of the internal conduit.

[0067] The external conduit 24 has a lumen extending between a proximal end 28 and a distal end 44, with a diameter ranging from about 0.007” to about 1.999”, preferably with an inner diameter of about 0.027”. The external conduit body 26 has a relatively rigid proximal section 40 connected to a relatively flexible distal section 42. A hub (Luer connector) 34 is attached to the proximal end of the external conduit body 26, which rests on a stress-relieving member 38. Figure 2The hub 20 is attached with a rotary hemostatic valve (RHV) 32 having an end cap 30 and a side arm 31. The end (locking) cap 30 acts as a locking assembly for the deflectable catheter, while the side arm 31 is used to introduce fluid for lubrication and possible visualization. When the cap 30 is fully open, the internal catheter 12 can be moved axially at will, resulting in the deflection of the distal end 48 as described below. The cap 30 can be tightened at any point during the deflection process to clamp and hold the internal catheter 12 in place, thereby locking the distal end 48 in place.

[0068] The deflectable end 48 of the internal conduit 12 is covered by a transverse support tube 50, which covers the columnar member described below. Support tube 50 ( Figure 2 and Figure 5 The transverse support tube 50 is a helically wound flexible coil. A radiopaque marking strip 54 is provided on the distal side of the transverse support tube 50, which is adhered to the distal end 58 of the inner conduit 10 at end 56.

[0069] The outer conduit 24 may have a lubricating liner 128 extending from the proximal end 28 to the distal end 44 to aid the movement of the inner conduit during deflection by reducing the coefficient of friction between the inner diameter of the outer conduit and the outer diameter of the inner conduit. The conduit includes a laser-cut tube and a distal braid. A reinforcing layer is provided on top of the liner. The reinforcing layer is topped with polymers of varying stiffness to form three distinct sections, with stiffness decreasing from the proximal section 118 to the distal section 122. The outer conduit body 26 includes a marking band 138 inserted at the distal end of the outer conduit body 26 at a midpoint of the inner diameter.

[0070] Various embodiments of external conduits, such as those with continuous open-pitch coils, are disclosed in '225 patent.

[0071] The conduit 10 includes a cylindrical member (e.g., a wire or tube) extending distally to the outer conduit 24 (or 524) and attached to the inner conduit, and surrounded by a limiting (supporting) tube to restrict lateral movement of the cylindrical member. As shown, the cylindrical member includes a column 140, the proximal end of which rests on or in a slot of a marking band 138. The proximal portion of the column 140 is inserted into the inner diameter (i.e., the conduit body wall) at the distal end of the outer conduit body 26. The column 140 has a generally rectangular cross-section.

[0072] The internal conduit 12 and the external conduit 24 are aligned and connected together with the marking tape 54 and the adhesive or solder joint 56 on the distal portion.

[0073] The alignment (distal ends substantially flush) of the distal ends of column 140 and internal conduit 12 is shown in Figure 5 middle.

[0074] Figure 5 The distal portion 150 is shown, having a lateral support tube 50 in place, which forms a cap for the column. The lateral support tube 50 is a flexible coil helically wound with a closed pitch made of platinum / iridium. Figure 4 The distal portion 150 prior to the attachment of the support tube 50 is shown.

[0075] '225 patent' Figure 12A The distal portion of the internal conduit under axial tensile load is shown without the lateral support tube 50. When the internal conduit body is axially pulled in the proximal direction by a load, the internal structure will tend to shorten, resulting in compression of the column 140. (From '225 patent) Figure 12B The effect is shown when the inner conduit body is axially pushed by a load in the distal direction without the lateral support tube 50. As shown, this applies a torque to the end of the column, causing it to bend.

[0076] '225 patent' Figure 13A and Figure 13C This illustrates the distal deflectable end under axial tensile load when the lateral reinforcement (support) tube 50 is provided. With the lateral support tube 50 in place and an axial tensile load applied, the column 140 can no longer be axially compressed due to the reinforcement of the column by the tube 50. As a result, the entire distal end, including the main (guidewire) lumen, deflects.

[0077] '225 patent' Figure 13B and Figure 13D This illustrates the effect when the internal conduit body is axially moved by a load 155 in the distal direction, with the lateral support tube 50 provided. This causes the distal end to... Figure 12B The bend is shown.

[0078] '225 patent indicates that, Figures 12A-13D The diagrams show the movement of the internal catheter proximally or distally, and the same effect can be achieved by moving the external catheter distally or proximally, or by moving both the internal and external catheters in the desired direction.

[0079] The deflection of the catheter via the columnar member is described in the '225 patent as follows. The bidirectional deflection of the distal end of the coaxial microcatheter can be decomposed into two distinct motions: axial tensile deflection and axial thrust deflection. Axial tensile deflection can be modeled as an eccentrically loaded column, while axial thrust deflection can be modeled as an eccentrically loaded beam.

[0080] Regarding axial tensile deflection, when there is no lateral support tube at the distal end of the conduit, the column member is modeled as an unsupported, eccentrically loaded column. This means that when the inner conduit is moved axially proximally using a force in the proximal direction, the distal end of the column (rectangular NiTiNorm) will tend to move axially towards its proximal end, resulting in compression (buckling) of the column. With the lateral support tube present, when the inner conduit is pulled axially using a force in the proximal direction, the column will attempt axial compression (buckling); however, it will be constrained by the lateral reinforcement tube 50. Since this end will no longer fail axially (in terms of compression), it will fail laterally (deflection).

[0081] Regarding axial thrust deflection, when there is no lateral support tube at the distal end of the conduit, the columnar member is modeled as an eccentrically loaded beam. This means that when the inner shaft is pushed axially with force, it will apply a moment to the end of the beam (e.g., a rectangular NiTiNorm), causing it to bend.

[0082] As described in the '225 patent, axial pushing and pulling can be considered in terms of the xy-axis. The axial pushing and pulling forces will occur along the x-axis, and the bending (deflection) will terminate at the point (x,y). Thus, for the compression of the column, resulting in the end bending to the yl position, the distal end of which is traveling in the -xl direction toward its proximal end (-x2).

[0083] The deflection at the distal end is achieved by axial movement rather than by pulling downward at the distal end, so that the bending is achieved by axial movement rather than by pulling along the direction of bending.

[0084] In the device disclosed in '225 patent, a reinforcing member (support tube) is positioned on the columnar member, and when the reinforcing member is attached to the deflectable conduit, the reinforcing member is part of the deflectable conduit. Figure 6 and Figure 8-11 In this invention, the device (catheter) is placed inside an external catheter (e.g., a suction catheter), and a deflection mechanism (i.e., a columnar member) is used to deflect the external catheter. The wall of the external catheter serves as a reinforcing / movement-restricting member / support tube, which achieves deflection in the same manner as the support tube 50. Therefore, the restricting member is not part of the device (catheter), and the device of this invention can be used to deflect other independent catheters inserted therein.

[0085] Figure 6 An embodiment of the bidirectional microcatheter (device) of the present invention with a deflectable tip is shown. The distal segment of catheter 300 is shown. Figure 6The device includes an external conduit 302 (also referred to herein as external member 302) and an internal conduit 316 (also referred to herein as internal member 316), the internal conduit 316 being positioned within and extending distally from the lumen of the external conduit 302 such that it has an exposed distal end 316a extending distally from the distalmost edge of the external conduit 302. The exposed distal end 316a can range, for example, from a minimum of 1 cm to greater than 5 cm, although other exposed lengths may also be considered. This distal extension positions the cylindrical member distal to the external conduit while still positioning the cylindrical member at a sufficiently large distance from the distal end of the internal conduit 316, as described below.

[0086] In this embodiment, the external conduit (component) 302 is a laser-cut stainless steel tube 303 with a non-laser-cut section 305 at its distal end 306, which has a laser-cut side hole 308. Other external conduit structures, such as those described in '225 patent, may also be used. Figure 6 Reference numeral 304 indicates the location where the laser-cut section ends and the non-laser-cut section begins. The outer conduit 302 is formed of a tube 303 covered with a polymer 310, which preferably covers the entire length of the laser-cut tube up to the end 304, thus exposing (uncovered) the non-laser-cut section 305 of the tube. An inner PTFE liner (not shown) extends the length of the tube 303 up to the end 304. This leaves the portion of the tube 303 below the non-laser-cut section 305 without a PTFE liner.

[0087] A marking tape 312 is partially inserted into the opening in the distal end 306 of the tube 303. If desired, the marking tape 312 can be welded, soldered, glued (or otherwise attached) to the appropriate position using the hole 308. The marking tape 312 can be inserted into the tube 303 up to the distal end 304, where it will impact the PTFE liner. The liner thus acts as a proximal stop for insertion into the inner liner. A post or column-shaped member 314 is rested (positioned) on top of the marking tape 312, which is inserted proximally into the tube 303 up to a point near the distal end 304. The post 314 can be welded, soldered, glued, or otherwise attached to the tube 303 or to the non-laser-cut section 305 using the hole 308 at its proximal end. The cross-section of the column-shaped member 314 can be circular or non-circular. The column-shaped member 314 can take various forms, such as wire or tube.

[0088] An internal conduit (component) 316 is positioned within an external conduit 303 and is inserted during manufacturing through a distal opening in a marking band 312, with its exposed distal region (segment) 316a extending distally to the marking band 312. The internal conduit 316 includes a lumen 323 terminating at the distal end of the conduit 316. The exposed distal region 316a has two parts: a more proximal region 316b to which a column 314 extends, and a more distal region 316c without the column 314. The proportions of these regions depend on the end of the column member. For example, the column member may have a length of approximately 1.5 cm. Other column lengths may also be considered. The length of segment 316c will depend on the position of the external member with the attached column member resting on the distal region 316a, i.e., the length of the column 314. As an example, if the length of the distal region 316a is 20cm and the length of the post 314 is 1.5cm, then the post 314 will be 18.5cm away from the distal end, therefore region 316c will be 18.5cm. Other lengths of segments 316a, 316b, and 316c, and other lengths of post 314, can be considered. Figure 7 In one embodiment, as an example, the columnar member terminates distally at a position less than half-marked relative to the external member 302, smaller than the distal segment 316a. The length of the distal region 316c, with its reduced lateral dimensions compared to the region 316b having the columnar member, is designed for passage through blood clots as described below, although other lengths are also conceivable. The internal catheter 316 can be constructed using methods such as those described in the '225 patent' or other methods. Furthermore, the internal catheter is merely one example of a usable internal catheter, as other internal catheter structures, such as those described in the '225 patent, can be used. However, modifications to this structure will be necessary to suit the novel and advantageous columnar structure and positioning of the present invention.

[0089] Figure 6 The internal conduit 316 employs a variable stiffness design, which utilizes an internal PTFE liner, a proximal braid resting on the PTFE liner, and an outer coating composed of polymers with varying stiffness. The polymer outer coating softens distally, making the distal section softer than the proximal section. At the very distal end of the internal conduit 316 is a platinum marking strip 321 covering the soft distal end. The internal conduit 316 may have a constant outer diameter, or alternatively, it may taper gradually along its length from proximal to distal until the marking strip 318, where the diameter decreases and becomes constant. The minimum length is preferably at least 1 mm, and the maximum length is preferably greater than 5 cm, although other lengths are also possible.

[0090] The exposed distal end 316a preferably always has the same flexibility; for example, the flexibility of segment 316c is preferably equal to the flexibility of region 316b. In this way, the column member 314 can be positioned (i.e., terminated distally) at any location along the length of this softer region, depending on the desired length of the contour-reducing segment 316c used to traverse the clot. The range of this soft distal segment 316a can be from about 15 cm to about 20 cm, although other lengths may also be considered. Proximal to the soft distal segment, the internal conduit has increased stiffness. This increased stiffness may begin only proximal to the distal segment 316a or even further proximal. In a preferred embodiment, the column member rests only in the softer distal segment 316a and not in the harder, more proximal region of the internal conduit 316.

[0091] A marking band 318 is positioned on the internal catheter 316 and marks the distal end of the proximal segment 316b of the exposed distal segment 316a. Below the marking band 318 is the distal end of a column (column-shaped member) 314. The column 314 may be welded, soldered, or bonded in place, or otherwise attached at its distal end to the marking band 318 and / or the outer surface of the internal catheter 316. At the distal end of the marking band 318 is an adhesive connector 320 to attach the marking band 318 to the distal segment 316a. The marking band 318 can be considered the boundary between the proximal region 316b (with the column-shaped member) and the distal region 316c (without the column-shaped member) of the exposed distal segment 316a. A marking band 321 located at the distal end 322 of the catheter 316 is distal to the marking band 318; the marking band 318 is distal to the marking band 312 attached to the external catheter 302. Note that although the post 314 is shown below the marking strip 318, it may also rest on top of the marking strip 318 and may be welded, glued, or soldered into place. The marking strip 318 may also have a cap (not shown) that covers the entire marking strip and is equal to or larger than the outer diameter of the outer conduit 302. Similarly, for this particular embodiment, the proximal end of the post 314 may be attached to the marking strip 312 and / or the outer conduit 302 using welding, soldering, gluing, or other forms of mechanical attachment. Thus, the post-shaped member 314 is attached to the outer conduit 302 at its proximal end and to the inner conduit 316 at its distal end.

[0092] As shown, the internal conduit 316 extends distally to the post 314. That is, the post 314 has a distal terminal attached to the internal conduit 316, for example via the aforementioned marking strip 318, wherein the distal terminal terminates proximally to the distal edge of the internal conduit 316. In this way, the elongated longitudinal extension of the internal conduit 316 (referred to as the distal region 316c) extends distally to the post 314, such that it does not have a post 314 extending along it. In some embodiments, as an example, the internal conduit 316 with a section of variable stiffness may have a length from about 15 cm to about 20 cm. The marking strip 318 is used to attach the post 314 and is spaced apart from the distal edge of the internal conduit 316. The length / spacing (with the exposed distal section 316c) can be designed / changed to traverse clots of different sizes. Therefore, the system consisting of the external conduit marking strip 308, the marking strip 318, and the post member 314 can be relatively different from... Figure 6 The internal catheter shown is positioned to provide segments 316c of varying lengths (without columns).

[0093] The internal catheter 316 has a distal region that is softer than the proximal region, and this softer region includes at least the distal region (segment) 316a. In this way, the region 316b extending from the column 314 (adjacent to it) and the elongated region 316c without the column 314 are located within the softer region of the internal catheter 316a. In other words, the proximal and distal ends of the column 314 are adjacent to the softer distal region of the internal catheter. The region proximal to this softer (more flexible) region is harder and may not deflect. That is, the internal catheter has a soft distal segment, which can be, for example, about 15 cm to about 20 cm, and the column member can rest on any part of it (but remain distal to the next more proximal segment of the harder catheter). In some embodiments, the distal region 316c may be softer than region 316b.

[0094] Figure 7 Another alternative embodiment of the distal portion 324 of a bidirectional microcatheter with a deflectable tip is shown. This structure is similar to... Figure 6The distal section 300 of the conduit is the same, except for the lateral support tube 326 covering the column (column-shaped member) 334 and located proximal to the distal region 316c of the exposed distal section 316a. The lateral support tube 326 consists of a stainless steel coil 328 and is covered with impregnated silicone resin 330. The lateral support tube 326 has a proximal end 332 with a mating end 304 and a distal end 336 with an adhesive joint 337 at its distal end. The proximal adhesive joint (not shown) attaches the support tube 326 to the external conduit. The support tube 326 can act as a reinforcement / restriction member for the column 314. Although this embodiment has a built-in movement restriction tube, and therefore does not have the advantage of using a separate conduit as a reinforcement / restriction member, the proximal distance between the column 314 and the distal end of the internal conduit has the advantages of deflection and passage through clots of a separate conduit as described in the following usage method.

[0095] Figure 8 and Figure 9 It shows Figure 6 The use of the deflectable microcatheter 300. When the inner catheter 316 is pulled back relative to the outer catheter 302 or the outer catheter 302 is pushed forward relative to the inner catheter 316 (or the inner catheter 316 and the outer catheter 302 move in opposite directions as desired), the post 314 will desirably bend or compress at region 314a, causing the exposed distal end 316a to move downward (in the direction away from the bend of the post 314). When the inner catheter 316 is pushed relative to the outer catheter 302 or the outer catheter 302 is pulled back relative to the inner catheter 316 (or the inner catheter 316 and the outer catheter 302 move in opposite directions as desired), the post 314 attached to the inner catheter 316 will begin to bend around region 338, and the exposed distal end 316a will move upward (in the direction toward the bend of the post 314). Note that region 316c will bend and at least a portion of region 316b may also bend.

[0096] Figure 10 It shows Figure 6 The distal portion 300 of the bidirectional microcatheter is removably inserted into a separate external catheter in the form of a suction catheter 340. In this system, the suction catheter 340 acts as a lateral support tube.

[0097] The aspiration catheter 340 has an internal lumen 343 and a distal end 348 with a distal opening. The distal portion of the microcatheter 300 is positioned such that the column 314 is within the lumen 343 of the aspiration catheter 340, and the exposed distal region 316c of the distal segment 316a extends distally to the distal end 348 of the aspiration catheter 340, such that at least a portion (and preferably at least 50%) of the distal region 316b is exposed from the aspiration catheter 300. (In some embodiments, this would mean at least 1 cm of the distal region, or alternatively at least 2 cm, although the external length is also taken into consideration). Positioning the exposed distal region 316a in this way allows the aspiration catheter 340 to act as a lateral support tube to limit movement of the column 314. That is, the aspiration catheter acts as a reinforcing member during axial tensile and axial thrust deflection in the manner described above with respect to the built-in support tube 50. Therefore, the column member 314 of the present invention does not require a support tube that is part of the conduit 300 (built into the conduit 300), but can use a separate (independent) conduit into which the column member 314 is inserted to restrict the movement of the column member, thereby achieving the deflection as described herein. Note that this is achieved because the column 314 is located within the distal portion of the suction conduit 340.

[0098] In some embodiments, the conduit does not have a longitudinally extending section with a reduced profile, so the column terminates distally near the distal edge of the internal member, but the conduit does not include a reinforcing tube, instead relying on a suction or other external conduit inserted into which it acts as a reinforcing member for deflection.

[0099] The internal lumen of aspiration catheters used to treat stroke often has a large pore size, varying from less than 0.030” to greater than 0.088”. Aspiration catheters 340 are typically constructed similarly to microcatheters with a PTFE liner 342, a reinforcing structure 344, and a polymer cover 346. The reinforcing structure 344 can be a braid, coil, laser-cut tube, or a combination of structures. The polymer cover 346 can be a variety of hardness gauges that gradually soften distally. Note that this is one type of construction for aspiration catheters, and other variations in the construction of aspiration catheters can also be considered. Furthermore, this is just a single example of a columnar member 314 being inserted into an off-the-shelf device or a standalone device to make that device deflectable. This concept can be applied to other catheters and devices that may not be covered under the general term aspiration; for example, an internal catheter with a columnar member 314 attached can be inserted into other catheters or tubular members to achieve deflection in the manner described herein when that catheter or tube acts as a reinforcing member for the columnar member 314.

[0100] Figure 11 It shows that the following is as follows Figure 8The distal portion 300 of the bidirectional microcatheter is shown deflected. However, the column 314 is now located within the aspiration catheter 340. When the column 314 at region 314a contacts the PTFE liner 342 of the external aspiration catheter (or, in embodiments without a liner, directly contacts the inner wall of the external aspiration catheter), the aspiration catheter 340 will deflect as shown. This may also result in deflection of the exposed distal section 316a of the internal catheter 316 and the guidewire 350 extending through the lumen of the internal catheter 316. Note that due to the large variations in the possible inner diameter and stiffness of the aspiration catheter design, the overall dimensions of the bidirectional catheter, including the column 314, will differ as the pore size of the aspiration catheter increases.

[0101] When used with aspiration catheters (or other independent catheters), the advantages of the deflectable catheter 300 with columnar member 314 can be referenced. Figure 12A and Figure 12B This is understandable. The purpose of the aspiration catheter 340 is to revascularize patients with ischemic stroke. One of the challenges in treating stroke is the intricate anatomy of the neurovascular system. Figure 12A A portion of the neuroanatomical structure 400, comprising the internal carotid artery (cavernous) 402, the ophthalmic artery 404, and the posterior communicating artery 406, is shown. This portion of the navigational anatomy presents a problem for larger ducts that tend to become stuck at the ophthalmic artery junction 408 due to the so-called vessel wall effect. Figure 12A As shown, due to the large lumen relative to the guidewire, the aspiration catheter 340 failed to follow the guidewire 350.

[0102] To overcome this, the company introduced distal access catheters, or distal auxiliary catheters, which are smaller catheters placed within large-pore aspiration catheters. In this setup, such as... Figure 12B As shown, the coaxial system allows the aspiration catheter 340 to be guided on the guidewire 350 by a smaller distal access catheter 352. However, a shoulder 354 remains between the catheters, which may damage the vessel wall and potentially lead to dissection and subarachnoid hemorrhage.

[0103] In addition to distal access or auxiliary catheters, the company has introduced larger guidewires and tapered microcatheters as possible solutions. The problem with these designs is that they lack the ability to truly change the direction of the entire distal end of the aspiration catheter. This problem is solved by inserting any of the bidirectional microcatheters described above into the lumen of the aspiration catheter. Using the bidirectional catheter of this invention, the user will be allowed to manipulate the guidewire and change the direction of the distal end of the aspiration catheter.

[0104] In addition to using aspiration catheters to treat stroke, interventional neuroradiologists sometimes use other clot retrieval tools, such as stent retrievers. These devices are sometimes used in conjunction with aspiration catheters; however, they require catheters with small inner / outer diameters to deliver and deploy through the clot. Because the clot should be traversed with the smallest possible catheter, companies have introduced tapered distal assist catheters as described above. While these designs provide a smaller distal profile for traversal, they still have the small shoulder problem associated with coaxial systems as described above. The bidirectional catheter of the present invention, with its exposed distal tip, allows for a small cross-section as well as full aspiration tip and guidewire control.

[0105] Figure 12C and Figure 12D A bidirectional microcatheter is shown, with its distal segment located within the aspiration catheter 340 and delivered on the guidewire 350. (See diagram) Figure 12C As shown, due to the size difference, a shoulder 354 exists between the distal segment 300 of the microcatheter and the aspiration catheter 340. Without assistance, this system would likely be able to... Figure 12A It contacts the ophthalmic artery junction 408 in a similar manner. However, as... Figure 12D As shown, manipulating the distal end of the bidirectional catheter via the columnar member 314 of the present invention causes the distal end 348 of the aspiration catheter 340 to change direction toward the center of the artery away from the junction 408. Note that the distal segment may also have a larger diameter to minimize the shoulder 354 transitioning to a smaller diameter 316a to pass through the clot.

[0106] Once the coaxial suction system reaches the clot, the initial step will be to pass through the clot to place a support retrieval device for clot removal. Figures 13A-13F The general steps for treatment are shown. Figure 13A The illustration shows the initial passage of a guidewire 350 through a clot 412 in a blood vessel 409 having an inner wall 410. For this step, a column 314 can be used to stabilize the distal exposed segment 316a by moving an internal catheter 316 (not shown) until region 314a of the column 314 contacts the wall 410. Once the guidewire 350 has passed through the clot 412, the column 314 is flattened, and the exposed distal region 316c of the exposed distal end 316a is pushed forward through the clot 412 (as shown). Figure 13B (As shown). Then as... Figure 13C Remove guidewire 350 as shown, and as... Figure 13D The deployment shown includes a stent retrieval device 358 with a delivery wire 356. The bidirectional microcatheter is then removed, and aspiration is achieved through the internal lumen 343 of the aspiration catheter 340 (see arrow 360), as... Figure 13EAs shown. Under suction, the support retriever 358 is then pulled into the clot using the conveying wire 356 (see arrow 380), and the entire coaxial system is then... Figure 13F Pull them together as shown to remove and remove the clot from the body. It should be noted that... Figures 13A-13F The steps for removing clots are merely an example, as access can be improved with fewer or more steps using the deflectable internal conduit / column member of the present invention. It is understood that, due to the absence of column 314, the lower profile of the distal segment 316c of the exposed distal region 316a of the internal conduit 316 facilitates passage through the clot.

[0107] In summary, according to a method of the present invention, a method for guiding a catheter through a vascular system is provided, the method comprising: inserting a first device into an external catheter, the first device having an inner member, an outer member, and a cylindrical member connected to the inner member and / or the outer member; moving one of the inner member or the outer member relative to the other when the cylindrical member is bent within the lumen of the external catheter to achieve axial compression of the cylindrical member, the inner wall restricting the movement of the cylindrical member such that a distal portion of the inner member is laterally deflected; and advancing the external catheter independently of or together with the device on the deflected distal portion to change the direction of the external catheter.

[0108] Note that the catheter of the present invention can be used to deflect a variety of other devices or tubular components, and is not limited to aspiration catheters.

[0109] While the foregoing description contains numerous details, these details should not be construed as limiting the scope of this disclosure, but rather as examples of preferred embodiments. Those skilled in the art will contemplate many other possible variations within the scope and spirit of this disclosure as defined by the appended claims.

[0110] Furthermore, those skilled in the art will understand that, without departing from the scope of the invention, elements and features shown or described in one embodiment may be combined with elements and features of another embodiment, and further features and advantages of the subject matter currently disclosed will be understood based on the provided description.

[0111] Throughout the above description, terms such as “approximately,” “about,” “roughly,” and “substantially” should be understood as allowing variation within any numerical range or concept associated with them. The intention is that the use of terms such as “approximately,” “about,” “substantially,” and “roughly” should be understood as including approximately 25% variation, or allowing manufacturing tolerances and / or design deviations.

[0112] The enumeration of numerical ranges by endpoints includes all numbers within that range.

[0113] Although terms such as “first,” “second,” and “third” may be used herein to describe various operations, elements, components, regions, and / or sections, these operations, elements, components, regions, and / or sections should not be limited by the use of these terms, as these terms are used to distinguish operations, elements, components, regions, or sections relative to each other. Therefore, unless explicitly stated otherwise, a first operation, element, component, region, or section may be referred to as a second operation, element, component, region, or section without departing from the scope of the invention.

[0114] Each claim is incorporated herein by reference as a further disclosure and represents an embodiment of the present disclosure. Furthermore, the phrases “at least one of A, B, and C” and “A and / or B and / or C” should be interpreted as including only A, only B, only C, or any combination of A, B, and C.

Claims

1. A system for manipulating a catheter, comprising: a) A first device, the first device having i) An external member having a proximal portion and a distal portion; ii) An internal member, which is coaxially positioned within the external member and extends distally to the external member and has a distal portion; iii) an elongated columnar member, said columnar member being attached to the inner member and extending outside the inner member; and b) An external conduit, independent of the first device and having a lumen, the first device being removably insertable into the external conduit and slidably positioned within the lumen of the external conduit, such that the cylindrical member is positioned within the lumen of the external conduit, the cylindrical member having a distal end terminating at the proximal edge of the distal edge of the internal member. c) Wherein, when one of the internal member or the external member moves relative to the other, the axial compression of the columnar member is restricted by the inner wall of the external conduit, thereby causing the distal portion of the internal member to deflect laterally to change the direction of the external conduit.

2. The system of claim 1, wherein, The internal component has a central longitudinal axis, and the columnar component is radially offset relative to the central longitudinal axis.

3. The system of claim 1 or 2, wherein, The external catheter is a suction catheter.

4. The system of claim 1 or 2, wherein, The cross-section of the column-shaped member is non-circular.

5. The system of claim 1 or 2, wherein, The system also includes a marking strip positioned on the internal member, and the columnar member is attached to the marking strip.

6. The system of claim 1 or 2, wherein, The columnar member is attached to the outer member at its proximal end and to the inner member at its distal end.

7. The system of claim 1 or 2, wherein, The internal component extends 2 cm from the distal end of the columnar component.

8. The system of claim 1 or 2, wherein, The distal end of the columnar member is adjacent to the softer distal section of the internal member.

9. The system of claim 1 or 2, wherein, A reinforcing member is positioned on the columnar component, and the reinforcing member contacts the inner wall of the external conduit during deflection.

10. The system of claim 1 or 2, wherein, The columnar component comes into contact with the inner wall of the external conduit during deflection.

11. The system of claim 1 or 2, wherein, The internal component has a distal segment that is softer than the proximal segment.

12. The system of claim 1 or 2, wherein, Lateral deflection is achieved when the columnar member is constrained by the inner wall of the external conduit in which the columnar member is positioned.

13. The system of claim 11, wherein, The column-shaped member is attached to the outer member at a first end and to the inner member at a second end.

14. The system of claim 13, wherein, The second end of the columnar member is positioned near the farthest edge of the inner member to leave an elongated extension of the inner member extending toward the far side of the columnar member.

15. The system of claim 14, wherein, The second end of the columnar member terminates near the softer distal section of the internal member.

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