Non-coring needle with inverted sharp edge

Abstract

The lancing device includes a tube (10) formed with a needle tip (12). The needle tip (12) includes a bevel having a bevel length (BL) that extends at a bevel angle from the base of the heel (14) to a sharp distal radially outer edge of the needle tip (12). An inverted edge (17) is formed on the heel (14) of the bevel as an inverted edge angle. The bevel angle is an acute angle, and the inverted edge angle is an obtuse angle.

Description

[Technical Field]

[0001] The present invention relates generally to a novel needle sharp edge designed to prevent coated guidewires from being damaged by abrasion or spalling of the coating. [Background technology]

[0002] A chronic total occlusion (CTO) is an arterial blood vessel blockage (typically plaque) that impedes blood flow. CTO can occur in both coronary and peripheral arteries and generally results from the same underlying cause: atherosclerosis.

[0003] One of the main difficulties in crossing a total occlusion is that the clinician does not know exactly how stiff the plaque is until they guide a guidewire through the occlusion. If the occlusion is relatively new, the plaque is likely soft enough that the guidewire can penetrate it. However, over the course of weeks or months, the occlusion may fibrose and calcify, making the plaque much stiffer and making it difficult, if not impossible, for the guidewire to cross the occlusion. Inability to cross the occlusion is the primary failure mode for CTO recanalization.

[0004] If the guidewire is unable to pass through the occlusion, a support catheter and a crossing catheter are used to support the guidewire through the occlusion. Such a crossing catheter may have a blunt tip.

[0005] When CTO lumen crossing is not possible, techniques have been developed to enter the subintimal space and re-enter the true lumen after occlusion. This so-called subintimal recanalization is a useful procedure and is widely used. One advantage of subintimal recanalization is that dissection of the subintimal space is more likely to result in a smooth lumen and improved blood flow than a lumen created by passing through a calcified plaque. However, technical failure occurs in approximately 25% of patients who undergo percutaneous subintimal recanalization, primarily due to an inability to re-enter the distal true lumen.

[0006] During percutaneous subintimal recanalization, if the true lumen cannot be re-entered by guidewire manipulation, a true lumen re-entry device must be used. Currently, there are several specially designed re-entry devices on the market, most of which use a straight or curved needle to re-enter the true lumen after occlusion with a guidewire.

[0007] Most currently available guidewires are polymer-coated, sometimes hydrophilically coated, and many have both polymer and hydrophilic coatings. Such coatings significantly reduce friction and improve pushability. However, using such coated guidewires with sharp needles carries the risk of damaging the guidewire when it is withdrawn due to abrasion and / or peeling of the coating by the sharp needle edge. This risk is even more serious and dangerous if the abrasion or peeling of the guidewire coating occurs within the patient's vasculature.

[0008] Several non-coring features can be added to the needle tip and are known in the art. Techniques such as gentle mechanical milling, sandblasting, or electropolishing of the needle heel can be used to slightly round the sharp, very thin edge of the needle heel. The rounding radius is very small due to the thin wall thickness of the needle hypotube. However, in prior art, only the sharp inner edge of the needle is rounded; the outer edge remains sharp to penetrate tissue or plaque. Therefore, in prior art, the outer edge must be masked to avoid rounding. Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention seeks to provide a novel non-coring needle device and process that allows for the safe passage of polymer-coated and / or hydrophilic-coated guidewires through a sharp needle tip, eliminating the risk of abrasion or removal of the coating by the sharp edge of the needle. [Means for solving the problem]

[0010] The non-coring needle tip of the present invention can be applied to any type of needle tip and any type of catheter, or any other device that includes a sharp needle. The non-coring needle tip of the present invention can be a straight or curved needle tip.

[0011] Simple prior art needles are typically made from metal hypotubes that are bevel cut at a sharp angle, usually about 20°. Sometimes the bevel cut is done at two different angles and is called a lancet needle tip.

[0012] In the prior art, when a guidewire is pushed forward through a device with a beveled needle tip at its distal end, the guidewire does not encounter any sharp needle edges and can pass safely without damaging its coating. Wear or abrasion of the guidewire coating occurs on the back or heel side of the needle tip as the guidewire is pulled back through the needle and into the device, encountering the very sharp edge on the heel side of the needle tip.

[0013] The non-coring needle tip of the present invention is based on reversing the direction of the sharp needle edge on the needle heel. In addition to reversing the sharp edge direction on the needle heel, the inner diameter edge of the needle can be rounded.

[0014] Additionally, even with obtuse angles on both the heel and needle puncture sides, rounding any angled lines or edges on the needle inner circumference can avoid abrasion or peeling of the guidewire coating.

[0015] The present invention will be more fully understood and appreciated from the following detailed description taken in conjunction with the drawings in which: [Brief explanation of the drawings]

[0016] [Figure 1] Diagram of needle bevel angle of prior art [Figure 2] Diagram of needles with different bevel angles according to the prior art [Figure 3A] 1 is a diagram of a needle tip having outer and inner cutting edges according to the prior art; [Figure 3B] 1 is a diagram of a needle tip having outer and inner cutting edges according to the prior art; [Figure 4A] FIG. 1 is a simplified schematic diagram of the mechanical removal or trimming of the sharp heel base of a prior art needle. [Figure 4B] FIG. 1 is a simplified schematic diagram of the mechanical removal or trimming of the sharp heel base of a prior art needle. [Figure 5A] Illustrates acute and obtuse angles of a needle tip that are rounded in one embodiment of the present invention. [Figure 5B] Illustrates acute and obtuse angles of a needle tip that are rounded in one embodiment of the present invention. [Figure 6A] Schematic cross-section of a standard needle tip of the prior art [Figure 6B] 1 is a schematic cross-sectional view of a needle tip with the sharp edge of the needle heel inverted in one embodiment of the present invention; [Figure 7] Schematic of a needle tip of the present invention with an inverted heel angle and rounded internal heel and needle puncture sides. [Figure 8] 1 is a schematic cross-sectional view of a prior art needle tip and a polymer-coated guidewire inside the needle. [Figure 9] Schematic cross-sectional view of the needle tip and polymer-coated guidewire inside the needle of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] A simple prior art needle 1, shown in Figure 1, is typically made from metal hypotube 10 with an acute bevel cut 11. The bevel angle can vary, as shown in Figure 2, but most typical needles have an acute angle of 15-30°. Sometimes the bevel cut is made at two different angles, and is called a lancet needle tip.

[0018] 3A and 3B, which show a standard bevel needle tip 12 of the prior art. The tip can be divided into region A, which is the piercing section 13 of the needle tip, and region B, which is the heel side 14 of the needle tip.

[0019] The piercing section 13 occupies approximately 180° of the forward section of the needle tip 12, and the heel section 14 occupies the other, more proximal 180° section of the needle tip 12. The outer circumferential angle of the piercing section 13 is an acute angle designed to cut tissue or plaque, and the inner circumferential angle of the piercing section 13 is an obtuse angle. The outer circumferential angle of the heel section 14 is an obtuse angle, and the inner circumferential angle of the heel section 14 is an acute angle.

[0020] When a guidewire is pushed forward through the hypotube 10 of a device or apparatus having a beveled needle tip 12 at its distal end, the guidewire does not encounter any sharp needle edges and can pass safely forward without damaging its coating. Wear or abrasion of the guidewire coating occurs on the back or heel side 14 of the needle tip as the guidewire is pulled back through the needle and into the device, encountering the very sharp edge of the heel side of the needle tip during retraction.

[0021] In the prior art, when needle tip 12 includes non-coring, such non-coring is based on trimming the inner periphery 16 of heel section 14 using a mechanical milling tool 4 (FIG. 4) or using different methods including electropolishing or sandblasting on certain heel regions.

[0022] 5A-5B. In embodiments of the non-coring needle tip 12 of the present invention, needle non-coring is based not only on rounding or rounding any internal sharp edges of the needle heel section 14, but also on reversing the direction of the sharp needle edge 17 on the needle heel side. In addition to reversing the sharp edge direction on the needle heel side, the needle heel inner diameter edge can be rounded. In other words, the bevel angle of the needle tip is acute, while the reverse edge angle of the reverse edge 17 is obtuse.

[0023] Reference is now made to Figure 6A, which shows a cross section of a standard prior art needle in which the edge 16 of the heel 14 is formed as an inward-facing acute angle.

[0024] 6B, which shows a cross-sectional view of needle tip 12 of tube 10 of one embodiment of the present invention. Sharp edges 17 of heel section 14 are reversed so that they face outward. Because sharp edges 17 face radially outward, any guidewire passing through needle tip 12 will not encounter a sharp angle in both the forward and backward directions.

[0025] The inverted edge 17 may have an acute angle of 15 to 45 degrees relative to the outer surface of the tube 10, i.e., the inverted edge angle is an obtuse angle of 105 to 135 degrees; alternatively, an obtuse angle of 105 to 130 degrees; alternatively, an obtuse angle of 105 to 125 degrees; alternatively, an obtuse angle of 105 to 120 degrees; alternatively, an obtuse angle of 105 to 115 degrees; alternatively, an obtuse angle of 105 to 110 degrees; alternatively, an obtuse angle of 100 to 135 degrees; alternatively, an obtuse angle of 100 to 130 degrees; alternatively, an obtuse angle of 100 to 125 degrees; alternatively, an obtuse angle of 100 to 120 degrees; alternatively, an obtuse angle of 100 to 115 degrees; alternatively, an obtuse angle of 100 to 110 degrees.

[0026] Referring now to Figure 5A, the bevel extends from the base of the heel to the needle tip and has a length BL. The inverted edge 17 has a length REL from the beginning of the heel at the base of the bevel at the needle tip to half of the bevel length BL; alternatively, the length of the inverted edge 17 may be less than half of the bevel length BL; alternatively, the length of the inverted edge 17 may be more than half of the bevel length BL; or alternatively, the length of the inverted edge 17 may be less than half of the bevel length BL and more than one-third of the bevel length BL.

[0027] Needles of the present invention can be manufactured with an inverted edge 17 by any suitable manufacturing process. The present invention can also be implemented by modifying existing needles to form an inverted edge 17. For example, to reverse the direction of the prior art heel section edge 16, one must first remove the sharp edge 16 using a mechanical tool or by any other means to obtain a straight wall in the heel section 14, and then begin to reverse the angular direction using a small mechanical milling or grinding tool or any other metal removal method known in the art. This procedure changes the shape of the heel section of the needle tip 12 and increases the needle tip open length, as seen in FIG. 7.

[0028] In another embodiment of the present invention, as seen in Figure 6B, any angled lines or edges on the inner needle surface, including even obtuse angles, on both the heel side and needle puncture side are rounded to form rounded edges 19 to avoid abrasion or peeling of the guidewire coating. The radius of the rounded edges 19 can be, but is not limited to, within the range of 0.1 to 0.5 mm.

[0029] Referring now to Figure 8, a guidewire 3 has a polymer coating 5 and is inserted into a prior art needle. The polymer coating 5 can be abraded and scraped off by the sharp edge 16 of the needle. In contrast to the prior art, in an embodiment of the present invention as shown in Figure 9, the polymer coating 5 of the guidewire 3 is not abraded at all by the everted edge 17.

Claims

1. 1. A lancing device comprising: a tube (10) formed with a needle tip (12), the needle tip (12) being a straight needle tip having a straight needle lumen passing therethrough, the needle tip (12) including a bevel having a bevel length (BL) extending at a bevel angle from the base of a heel (14) to a sharp distal radially outer edge of the needle tip (12); and An inverted edge (17) which is composed of a flat surface on the heel (14) and rounded edges on both the heel side and the needle puncture side, and the inverted edge angle between the extension of the outer wall of the needle on the heel side of the bevel and the flat surface on the heel (14) is an obtuse angle. Equipped with Puncture device.

2. 2. The lancing device according to claim 1, wherein the inverted edge angle is an obtuse angle of 100 to 135 degrees.

3. 2. The lancing device according to claim 1, wherein the inverted edge angle is an obtuse angle of 100 to 130 degrees.

4. 2. The lancing device according to claim 1, wherein the inverted edge angle is an obtuse angle of 100 to 125 degrees.

5. 2. The lancing device according to claim 1, wherein the inverted edge angle is an obtuse angle of 100 to 120 degrees.

6. 2. The lancing device according to claim 1, wherein the inverted edge angle is an obtuse angle of 100 to 115 degrees.

7. 2. The lancing device according to claim 1, wherein the inverted edge angle is an obtuse angle of 100 to 110 degrees.

8. 2. The lancing device of claim 1, wherein the bevel has a bevel length, and the inverted edge (17) has a length extending from the beginning of a heel at the base of the bevel at the needle tip to a maximum of half of the bevel length.

9. 2. The lancing device of claim 1, wherein the bevel has a bevel length and the inverted edge (17) has a length that extends from the beginning of a heel at the base of the bevel at the needle tip to more than half of the bevel length.

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