Patent Application
20170367728
This application claims the benefit of Chinese patent application No. CN 201610458021.7 filed Jun. 22, 2016, the entire disclosure of which is incorporated herein by reference.
Described are medical devices, in particular, membrane puncturing devices for endovascular surgery.
Aortic dissection occurs when a tear in the tunica intima of the aorta causes blood to flow between layers of the wall of the aorta, forcing the layers apart. Endovascular repair of aortic dissection in domestic and foreign vascular surgery centers has been carried out. A surgery needs to establish a channel approaching from the femoral artery, guide a guidewire to the breaking part of the dissection, implant a stent graft to the breaking part of the dissection, thereby covering the breaking part and expanding the true lumen to restore normal hemodynamics and achieve the purpose of repairing the dissection. However, the distance between an aortic rupture and a branch of the aortic arch (left clavicle artery, carotid artery, anonyma) is less than 1 cm; or in other cases, the aneurysm can overgrow over the aortic arch. The branch of the aortic arch will be covered during endovascular treatment, because this is needed to reconstruct the branch of the aortic arch.
Budd-Chiari syndrome refers to the obstruction of hepatic venous reflux resulting from stenosis or complete obstruction of the retrohepatic segment of the inferior vena cava and/or hepatic veins. The common types of Budd-Chiari syndrome include stenosis or obstruction of the inferior vena cava. Budd-Chiari syndrome can be further grouped into inferior vena cava simple diaphragm type, limited stenosis of the inferior vena cava, and limited obstruction of the inferior vena cava. Moreover, other types of Budd-Chiari syndrome include diffusion stenosis or obstruction of the inferior vena cava commonly caused by the formation of massive thrombosis and stenosis, or obstruction of hepatic veins. Interventional therapy with a small wound has been widely accepted as a solution for patients with incomplete or complete proximal membranous obstruction of the inferior vena cava, segmental stenosis of the inferior vena cava, no thrombus at locations distal of obstruction site, and unobstructed hepatic veins.
For this kind of interventional therapy involving passing through the diaphragm, the prior art interventional therapy includes puncturing a membrane of a stent, a site\s of stenosis, using a membrane puncturing needle directed by one or more guide wires, which thus allows the guide wires to pass through the membranes and direct further balloon expansion, and as a result the stent is implanted or the stenosis is eliminated. To note, it is important to ensure that the needle is directed accurately to the center of the membrane with appropriate strength when utilizing a membrane puncturing needle. If the needle is incorrectly directed to the periphery of the membrane instead of the center of the membrane, the needle may break the vessel. Moreover, as there is normally a long distance from the puncturing point to the membrane site. Due to insufficient support of the current medical devices, superior difficulty in adjusting the strength, lack of control of the accurate location, and length of puncturing needle, prior art treatment methods face challenges when puncturing the membrane via membrane puncturing needles. With regard to these challenges, utilization of prior art membrane puncturing needles may have disadvantages such as risks of breaking the membrane, long operation periods, relatively low success ratio, and high risks of accidental injury. During operation, inaccurate puncture and over-puncture may break veins, or even accidentally puncture into pleura or pericardium leading to unnecessary injury.
Considering the shortcomings membrane puncturing needles in the prior art, the present improved devices provide a membrane puncturing device with much better flexibility and vessel passability, which can achieve better results and allow for more safe and accurate membrane puncture.
The described membrane puncturing device includes a membrane puncturing needle, a double-layer sheath, and a positioning stent. The double-layer sheath includes an inner sheath sleeved outside the membrane puncturing needle and an outer sheath sleeved outside the inner sheath, wherein the inner sheath, the outer sheath, and the membrane puncturing needle can move along an axial direction relative to each other. The positioning stent is woven by at least one wire. The distal end of the positioning stent is connected to the inner sheath and the proximal end of the positioning stent is connected to the outer sheath. Expansion and contraction of the positioning stent can be controlled by relative movement between the inner sheath and the outer sheath.
In one embodiment, a radiopaque marker is included in the device. The radiopaque marker includes at least one of a radiopaque wire, a radiopaque ring, a radiopaque point. In some embodiments, the radiopaque wire is contained in at least one wire, the radiopaque ring is disposed on the positioning stent, the radiopaque point coated on the wire, and combinations thereof.
In another embodiment, the distal end of the positioning stent is fixed with the inner sheath by hot-melt adhesion and/or the proximal end of the positioning stent is fixed with the outer sheath by hot-melt adhesion.
In still another embodiment, the positioning stent is woven by crossing-overlapping at least one wire. The wires peripherally adjacent to each other form diamond grid units. The obtuse angles of the diamond grid units range from 91 to 179 degrees, from 100 to 160 degrees, from 110-150 degrees, from 115-140 degrees, or from 120-135 degrees. The shape of the cross section of the wires is selected from the group consisting of round, ellipse, trapezoid, diamond, or rectangle. The wire is made from at least one of nickel-titanium alloy, 304 stainless steel, 316L stainless steel, L605 cobalt-chromium alloy, and MP35N alloy. The wire diameter of the at least one wire ranges from 0.005 inches to 0.02 inches. The lay of braiding of the positioning stent ranges from 0.6 mm to 1.5 mm. The maximum outer diameter of the positioning stent, when it is expanded, ranges from 5 mm to 40 mm. The positioning stent can be a spherical stent, a fusiform stent, a cylindrical stent, or a conical stent. Alternatively, the positioning stent is formed by forward braiding and backward braiding the at least one wire.
In another embodiment, the membrane puncturing needle has a puncturing tip for puncturing a membrane and the puncturing tip has a radiopaque marker. Moreover, the end opposite of the puncturing tip of the membrane puncturing needle has a scale marker. In some embodiments, the membrane puncturing device also has a limiting apparatus that is engaged with the end opposite of the puncturing tip of the membrane puncturing needle for limiting movement of the membrane puncturing needle. The membrane puncturing needle is hollow, and the hollow cavity can be used for allowing guidewires to pass there through. The membrane puncturing needle has an outer diameter ranging from 0.3 mm to 1.5 mm. Alternatively, the membrane puncturing needle is a flexible optical fiber.
In other embodiments, the membrane puncturing device also includes a locking apparatus that is connected to the proximal end of the inner sheath. The locking apparatus is for locking the distance between the distal end of the inner sheath and the distal end of the outer sheath.
The present devices have the following advantageous effects over the prior art. The presently described positioning stent is woven by at least one wire, such that the positioning stent is not breakable, has enhanced tensile strength, has excellent radial positioning capability and flexibility, and thus it will adapt well to vessels.
The woven positioning stent has a hollowed-out structure (the wires adjacent to each other peripherally form diamond grid units), and therefore, the stent does not influence blood flow when the membrane is punctured. And the helical and grid structures of the woven stent itself have an excellent anchoring effect to prevent shifting of the positioning stent when puncturing the membrane.
The positioning stent is gradually released so as to reduce damage on the inner wall of the vessel.
Meanwhile, the radiopaque marker disposed on the positioning stent (e.g., radiopaque wire, radiopaque ring, radiopaque point, and the like) may make the positioning stent clearly visible in the body.
In addition, the positioning stent may be connected to the double-layer sheath by hot-melt adhesion. That is to say, the hot-melt adhesion is performed on the inner and the outer sheaths themselves. In comparison with conventional glue adhesion, such hot-melt adhesion not only has high connection strength, great tensile strength, and excellent passability, but also has no potential risk from the addition of other components.
The radiopaque marker is disposed on the distal end of the membrane puncturing needle (puncturing tip) such that the distal end of the membrane puncturing needle can be clearly visible, thereby accurately puncturing the membrane. The scale marker is disposed on the proximal end of the membrane puncturing needle (the end opposite to the puncturing tip) to indicate membrane crossing length, and the limiting apparatus is arranged to control membrane crossing length, such that damage caused by over-puncture can be avoided, thereby accurately and safely puncturing the membrane. Further, the hollow cavity of the membrane puncturing needle allows the guidewire to pass there through, such that the guidewire can be further deployed after puncturing the membrane, so as to provide convenience for further operation.
The described membrane puncturing devices for endovascular surgery, such as diaphragm-type Budd-Chiari syndrome and opening a hole on a membrane covered stent in vivo, have excellent flexibility and vessel passability, which can meet various requirements and safely and accurately puncture the membrane. Meanwhile, since the positioning stent and the distal end of the membrane puncturing needle are radiopaque and the limiting apparatus and the scale marker are connected to the proximal end of the membrane puncturing needle, the membrane can be punctured accurately and safely.
Several aspects of the invention are described below in details with reference to appended drawing and specific embodiments for illustration. Members in the drawings are used to illustrate the principles of the present invention.
The structures and/or the materials in the examples of the present description, which are well known in the art, are not shown or described in detail. The features, structures, and/or characteristics may combine together in one or more embodiments. In addition, those skilled in the art would understand that the embodiments are set forth to provide a full understanding of the invention, rather than limit the protection scope thereof. Those skilled in the art would also understand that the components in the embodiments, as mentioned and as shown in the drawings, can be arranged or designed in different ways or at different scales.
As shown in
In some embodiments, the positioning stent 3 includes a radiopaque marker. In one embodiment, the radiopaque marker may include a radiopaque wire contained in at least one wire, a radiopaque ring disposed on the positioning stent (e.g., the radiopaque ring may be disposed on the distal and proximal ends of the stent, as C-type ring or round ring), a radiopaque point applied on the wire, and a combination thereof. The radiopaque marker may be other markers which are able to make the positioning stent radiopaque. The radiopaque feature of the positioning stent may be used for indicating the location of the positioning stent in the body so as to ensure that the membrane puncturing needle accurately punctures the membrane.
In this embodiment, the positioning stent 3 is woven through crossing-overlapping at least one wire. The wires peripherally adjacent to each other form a diamond grid unit. In some embodiments, the crossing-overlapping refers to the circumstance that wire a is above wire b when wire a contacts wire b at the first time, and when wire a contacts wire b at the second time, wire a pass below wire b and thus they cross with each other. The obtuse angle of the diamond grid unit ranges from 91 to 179 degrees, from 100 to 160 degrees, from 110 to 150 degrees, from 115 to 140 degrees, or from 120 to 135 degrees. In one embodiment, the obtuse angle of the diamond grid unit ranges from 120-135 degrees. The lay of braiding of the positioning stent (i.e., the straight-line distance between two cross points along the axial direction) is between 0.6 mm and 1.5 mm, and in some embodiments 1.0 mm (in the contracted state as shown in
In this embodiment, the positioning stent is formed without braiding at forward and backward directions (i.e., the wires firstly wind via front to back and then wind in reverse). Two ends (free ends) of the wires are located on two ends of the positioning stent, which can be fixed with the inner sheath 21 and the outer sheath 22. In other embodiments, the positioning stent 3 can be formed by forward and backward braiding the at least one wire, at this time, two ends (i.e., radial ends) of the positioning stent are not open, both of which are fixed with the inner sheath 21 and the outer sheath 22, respectively.
In this embodiment, the distal end of the positioning stent is fixed with the inner sheath 21 by hot-melt adhesion and the proximal end of the positioning stent is fixed with the outer sheath 22 by hot-melt adhesion. In some embodiments, the hot-melt adhesion means that, for example, the distal end of the inner sheath is heated and partially molten and then the distal end of the positioning stent is extended into the molten part of the distal end of the inner sheath, followed by being pressed and cooled, such that the distal end of the positioning stent can be fixed with the distal end of the inner sheath. In comparison with common connections using glue, the hot-melt adhesion does not need new adhesive materials, because it uses the sheath itself for adhesion instead. Therefore, the hot-melt adhesion has a high connection strength and no potential risk, which is rendered due to the introduction of other components for the clinic environment. Nevertheless, the positioning stent can be fixed with the inner sheath 21 and the outer sheath 22 respectively using other adhesion methods. For example, medically acceptable adhesives can be used to fix the positioning stent with the inner sheath and the outer sheath.
As shown in
The outer diameter of the membrane puncturing needle ranges from 0.3 mm to 1.5 mm. In one embodiment, the membrane puncturing needle is hollow, and the hollow cavity allows guidewires 6 to pass therethrough. In another embodiment, the membrane puncturing needle is a flexible optical fiber and it is used to puncture the membrane by laser.
The membrane puncturing device also includes a locking apparatus 4 connected with the proximal end of the inner sheath, for locking the distance between the distal end of the inner sheath and the distal end of the outer sheath. In some embodiments, he locking apparatus 4 is a fastening screw. The inner sheath can be locked and remain fixed by tightening such a fastening screw, such that the distance between the inner sheath 21 and the distal end of the outer sheath 22 can be fixed.
The membrane puncturing device also includes an inner sheath joint 51, an outer sheath joint 52, and a membrane puncturing needle joint 53. The inner sheath joint is connected with the proximal end of the inner sheath, the outer sheath joint is connected with the proximal end of the outer sheath, and the membrane puncturing needle joint is connected with the proximal end of the membrane puncturing needle. These joints are convenient for doctors to move the inner sheath, the outer sheath, and the membrane-puncturing needle when performing operations. In some embodiments, a washing hole 54 is disposed on the outer sheath joint 52, for washing and imaging in the double-layer sheath.
In addition, as shown in
Referring to
The membrane puncturing device can be disposable or can be packaged in bags, boxes, or other suitable containers after sterilizing by any suitable technique. For example, the disposable membrane puncturing device can be packaged with a protective coil for sale. After taking out the membrane puncturing device, it can be cleaned by normal saline.
Embodiments also provide a method for operating the above membrane puncturing device, including the following steps:
During an operation, the puncturing needle, scalpel and sheath and the like need to be sterilized prior to using membrane puncturing device. And since the guidewire and the protective coil for the guidewire are sold together, sufficient heparinized normal saline should be injected into the coil using the syringe prior to taking the guidewire out, so as to readily hydrate the guidewire's coating layer.
The terms as used herein should be considered as illustrative, but not restrictive. Those skilled in the art would understand that many modifications may be made without departing from the spirit thereof. Thus, the scope of the present invention should be defined by the accompanying claims. Unless defined otherwise, all terms used herein should be understood as having their broadest meaning.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201610458021.7 | Jun 2016 | CN | national |
