Biopsy needle set with reduced deflection and improved targeting

Abstract

To provide a biopsy needle set with reduced deflection and improved targeting.SOLUTION: The biopsy needle set includes a biopsy needle with a tip that distally terminates in a laterally extending cutting edge spaced from a bottom surface of the needle. A proximal cradle of the needle has a floor below the central axis of the needle and a row of teeth extending upwardly from each side of the floor to about the central axis. Within each row, the teeth are spaced apart from one another, and the teeth of the two rows are staggered such that some cross-sections of the cradle include only one tooth and some do not. The outer surface of the cradle holds the biopsy needle in the center of a cannula and abuts the inner surface of the cannula so as not to bend, thereby better targeting the subject's tissue for sampling.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] This patent relates to needle biopsy devices and methods, including, but not limited to, devices for obtaining tissue samples of prostate tissue. [Background technology]

[0002] Notched biopsy needle sets have long been used to obtain tissue samples. Standard of Care (SOC) needle sets include a needle, sometimes called a stylet or core collector, with a sharp tip designed to penetrate tissue, followed by a proximal notch through which surrounding tissue can protrude, and a shaft. The needle set also includes a cutting cannula, which slides coaxially around the needle and has a sharp distal edge. Needle sets can be used with fully manual instruments, in which a medical professional manually pushes the needle into the tissue until the notch is within the target tissue, then manually pushes the cannula toward the needle tip to cut the tissue that has entered the notch and deposit it into the notch while withdrawing the needle set from the tissue. With semi-automatic instruments, the practitioner manually drives the needle into the tissue in the same manner, but then releases a spring-loaded cutting cannula to cut and deposit the tissue sample. Fully automated instruments spring-load both the needle and the cannula. The medical professional inserts the needle into the patient with the cannula covering the notch until the needle tip is near or in the target tissue, then releases the needle to fire distally into the tissue to be sampled, then fires the spring-loaded cutting cannula distally to cut the sample into the notch, then withdraws the needle set from the patient and retracts the cannula to expose and retrieve the tissue sample from the needle notch for initial evaluation and / or transport to a pathology laboratory.

[0003] One of the key requirements in such procedures is to obtain tissue samples that are as large in volume, cross-section, and length as possible, given the cross-section of the needle set, so that they faithfully represent the tissue being cut, while another is to ensure that the biopsy needle bends at its thinner, notched portion, avoiding missing the intended target tissue and / or disturbing the living tissue.

[0004] This patent document is directed to apparatus and methods that meet such needs and other needs and provide other improvements to biopsy needle sets and related methods. Summary of the Invention [Means for solving the problem]

[0005] According to some embodiments, a biopsy needle set comprises a biopsy needle extending along a central axis at an intermediate level between the top and bottom areas of the needle, said needle comprising a tip, a cradle proximal to the tip, and a shaft proximal to the cradle, the tip being at a distal end of the tip and including upper and lower facets that converge distally to form a laterally extending distal cutting edge, the cradle being between said central axis and the bottom area of ​​the needle and comprising an upwardly facing floor having sides flanking the central axis, and a row of teeth extending upward from each side of said floor to a level approximating the level of the central axis, the teeth in each row being spaced apart from each other along the central axis, and said laterally extending distal cutting edge being spaced apart from said bottom area of ​​the needle but below the level of said cradle floor.

[0006] According to some embodiments, the biopsy needle set may further include one or more of the following: (a) the distal cutting edge may be spaced apart from the bottom extent of the needle by a distance approaching one-third of the distance from the bottom extent of the needle to the level of the floor of the cradle; (b) the distal cutting edge may be located 15,000 inches plus or minus 5,000 inches from the bottom extent of the needle; (c) the upper and lower facets may comprise two side-by-side lower facets; (d) the lower facets may comprise two lower facets below the laterally extending cutting edge and converging into upper and lower edges extending proximally therefrom; (e) the upper and lower facets may comprise two lower facets each shorter along the central axis than the upper facet; and (f) the tines may be spaced apart such that some cross sections of the cradle are spaced apart from the tines. (g) the laterally extending distal cutting edge may be V-shaped in top view; (h) the laterally extending distal cutting edge may include two portions each extending along a respective straight line; (i) the laterally extending distal cutting edge may extend along a single straight line; (j) the laterally extending distal cutting edge may extend along at least one curve; and (k) the set may further comprise a hollow cutting cannula configured to slide distally and proximally over the biopsy needle along a central axis such that an outer bottom surface of the cradle and outer surfaces of the teeth abut against an inner surface of the cannula to hold the needle centered in the cannula to resist bending of the needle as a portion of the cradle extends distally from the cannula. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 10 is a left side view of a distal portion of a biopsy needle according to some embodiments. [Figure 2] FIG. 10 is a left-side close-up view of a distal portion of a biopsy needle, according to some embodiments. [Figure 3]FIG. 10 is a perspective view of a distal portion of a biopsy needle from a perspective of the left side of the needle, according to some embodiments. [Figure 4] FIG. 1 is a perspective view of a distal portion of a biopsy needle, according to some embodiments, from a perspective distal and to the left of the needle. [Figure 5A] FIG. 10 is a left side view of a portion of a biopsy needle according to some embodiments. [Figure 5B] 1 is an equivalent view of a portion of a prior art standard of care biopsy needle. [Figure 6A] FIG. 10 is a left perspective view of a portion of a biopsy needle according to some embodiments. [Figure 6B] 1 is an equivalent perspective view of a portion of a prior art standard of care biopsy needle. FIG. [Figure 7] FIG. 1 illustrates a comparison of using a standard of care (SOC) biopsy needle set and a needle set using a biopsy needle described in this patent specification, according to some embodiments. [Figure 8] FIG. 1 is a front view of a biopsy needle according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0008] A detailed description of exemplary preferred embodiments is provided below. While several embodiments are described, the novel subject matter described in this patent specification is not limited to any one or combination of the embodiments described herein, but instead encompasses numerous alternatives, modifications, and equivalents. In addition, while numerous specific details are set forth in the following description to provide a thorough understanding, some embodiments can be practiced without some or all of these details. Moreover, for the sake of clarity, certain technical material known in the relevant art has not been described in detail to avoid unnecessarily obscuring the novel subject matter described herein. It will be apparent that one or more individual features of specific embodiments described herein can be used in combination with features or other features of other described embodiments. Like reference numbers and characters in the various drawings indicate like elements.

[0009] FIG. 1 is a left side view of a portion of a biopsy needle 100, according to some embodiments, and FIG. 2 is an enlarged view of the distal portion of the biopsy needle. The needle extends along a central axis A and includes a tip 102, a cradle 104 proximal to the tip, and a shaft 106 proximal to the cradle. The central axis A is at the center of a cross section through the shaft 106. The bottom extent of the needle 100 is at level B, and the top extent of the needle 100 is at level C. The shaft 106 has a portion extending further to the right in FIGS. 1 and 2 (not shown in FIGS. 1 and 2) and has a proximal end configured to be attached, fixed, or removable to an instrument not shown in FIGS. 1 and 2 but described below. The biopsy needle 100 is typically part of a biopsy needle set that further includes a cutting cannula 108. The proximal portion of the cannula 108 is shown in FIG. 2. Cutting cannula 108 has a sharp distal end 108a and is configured to slide distally and proximally around biopsy needle 100. Cannula 108 extends further to the right and has a portion (not shown in FIG. 2) configured for attachment to an instrument as described below.

[0010] It should be clear that position terms such as upper, lower, top, bottom, etc. refer to the orientation of biopsy needle 100 as shown in Figures 1 and 2, and that different orientations of needle 100 relative to the observer will require these position terms to be adapted accordingly.

[0011] FIG. 3 is a perspective view of the distal portion of biopsy needle 100 from the perspective of the needle's left side, according to some embodiments, showing cradle 104's upward-facing floor 104a, a left row of teeth 104b extending upward from the left side of floor 104a, and a right row of teeth 104c extending upward from the right side of floor 104a. As seen in FIG. 2, floor 104a is at level D below central axis A. Teeth 104b, like teeth 104c, extend to or approximately to the level of central axis A, i.e., to or approximately halfway through the diameter of biopsy needle 100 at the cross section of shaft 106. Teeth 104b of the left row of teeth are axially spaced apart from one another. Teeth 104c of the right row of teeth are also axially spaced apart from one another. For example, the teeth in a row can be axially spaced apart as shown in FIG. 1 and scaled to the dimensions of a particular biopsy needle. 1, each tooth is spaced from an adjacent tooth in the same row by two to three times the axial length of the tooth at the level of the cradle floor 104a. In this example, the most distal tooth is spaced from the tip 102 by at least the axial length of one tooth, and the most proximal tooth is spaced from the shaft 106 by at least the axial length of the tooth. As an example, for a cradle 104 with an axial length of 20 mm, one row can have three teeth and the other row can have four teeth.

[0012] Preferably, the left and right rows of teeth are staggered such that some cross sections through the cradle 104, such as cross section F, include teeth such as 104b or 104c, while some cross sections, such as G, do not include such teeth. For example, cross sections such as G do not include structure above the cradle floor 104a.

[0013] An important feature of biopsy needle 100 is the shape of the distal portion of tip 102, including how distal cutting edge 102a is elevated above level B of the bottom extent of biopsy needle 100 and how this cutting edge 102a is elongated (which can be flat or curved, such as somewhat concave or convex) in a direction parallel or nearly parallel to cradle floor 104a.

[0014] As seen in FIG. 2, tip 102 terminates distally in a sharp distal cutting edge 102a formed at the convergence of upper facet 102b and lower facet 102c. Cutting edge 102a is at level E above level B of the bottom extent of needle 100 but below level D of floor 104a of cradle 104. Level E of cutting edge 102a is preferably about one-third of the distance between levels B and D above level B, although this may vary somewhat. In a specific example, the distance is 15,000 inches (0.00381 cm), or ±5,000 inches (0.00127 cm).

[0015] FIG. 4 is a perspective view of a distal portion of biopsy needle 100, according to some embodiments, from a perspective of the distal and left side of the needle. The most distal of teeth 104c is not visible in FIG. 4. Cutting edge 102a has left and right portions 102a1 and 102a2 formed at the convergence of upper facet 102b with lower left and right facets 102c1 and 102c2. Lower facets 102c and 102c2 converge at edge 102d, with all three facets meeting at point 102c. In a top view of needle 100, cutting edge 102a is V-shaped. As seen in FIG. 2, angle α of upper facet 102b relative to central axis A is less than angle β of lower facet 102b relative to central axis A.

[0016] FIG. 5A is a left side view of a portion of biopsy needle 100, and FIG. 5B is an equivalent view of a portion of a prior art standard of care biopsy needle 500. In either case, the biopsy needle is typically part of a needle set that also includes a cutting cannula. Cutting cannula 108 is shown schematically in FIG. 5A, and a similar cutting cannula 508 is shown schematically in FIG. 5B. One important difference is that standard of care biopsy needle 500 does not have teeth in its notch 504a, while needle 100 has teeth 104b and 104c. Another important difference is that standard of care needle 500 terminates distally at point 502a, which is at level K of the base of needle 500, while needle 100 terminates distally at a laterally extending edge 102a (rather than a point) that is spaced from level B of the base extent of needle 100 and includes edges 102a1 and 102a2.

[0017] 6A and 6B are otherwise similar to FIGS. 5A and 5B, respectively, but show the respective biopsy needles from a perspective distal and to the left of needle tip 102 and 502. FIG. 6B shows that the needle tip terminates distally at the point where side facets 502a and 502b meet top facet 502c. In contrast, as seen in FIG. 6A, tip 102 terminates distally at a laterally extending edge 102a (including edges 102a1 and 102a2) that is not a point. FIGS. 6A and 6B also show that cutting edge 102a is elevated from the bottom extent of needle 500, while point 502a is at the level of the bottom extent of needle 100.

[0018] These differences have important consequences for the intended use of the biopsy needle set, as explained below with respect to typical uses of the biopsy needle set.

[0019] Biopsy needle sets, such as those shown in FIGS. 5A, 5B, 6A, and 6B, are typically used as part of a biopsy instrument in which a medical professional obtains tissue samples to observe for signs of a condition, such as the presence and nature of malignant cells. These instruments can be manual, semi-automatic, or fully automatic. A manual instrument is described in U.S. Pat. No. 3,447,423, incorporated herein by reference. A biopsy needle, such as needle 500 (although possibly with a differently shaped distal end), is fixedly attached to a handle and extends distally therefrom, and a cutting cannula, such as cannula 508, is attached to the handle so as to slide distally and proximally around the needle. The medical professional manually inserts the needle distally into the patient's tissue until notched portion 504 enters the tissue of interest, and then manually pushes cannula 508 distally to cut the tissue protruding into notch 504. The medical professional then withdraws the needle and cannula from the patient and pulls the cannula proximally relative to the needle, exposing the tissue sample in the notch and removing it from the notch for evaluation. A semi-automated biopsy instrument is described in U.S. Pat. No. 4,907,599, incorporated herein by reference. It differs from manual instruments in that a spring-loaded cannula is released to fire distally over the needle to cut tissue protruding into the needle notch. An automated instrument is shown in U.S. Pat. No. 6,358,217 as one mode of operation, and differs in that both the needle and cannula are spring-loaded. The medical professional inserts the needle into the patient with the cutting cannula covering the needle notch until the distal end of the needle-cannula combination is near the target tissue, and then releases the spring-loaded needle to fire distally so that its notch or cradle can enter the target tissue. After the tissue is projected into the notch or cradle, the spring-loaded cutting cannula is fired distally to sever the tissue sample.

[0020] The biopsy needle 100 and cutting cannula 108 have proximal ends (not shown) that can be appropriately adapted to secure the proximal ends or portions of the needle and cannula to a biopsy instrument in the manner shown in the aforementioned Patents Nos. 3,447,423, 4,907,599 and 6,358,217.

[0021] The goal of a tissue biopsy medical procedure is to remove from a patient a tissue sample that is as large and as intact as possible given the size of the biopsy needle and cannula, i.e., that is, one that is as similar in shape and properties to how the tissue sample was in the living tissue. It is important to improve targeting of the tissue of interest by helping the needle remain centered in the cannula, improving the size and integrity of the tissue sample in medical procedures that use biopsy instruments.

[0022] The needle tip 102 and cradle 104 described in this patent specification have a laterally extending cutting edge 102a that is elevated from the level of the bottom area of ​​the needle, further contributing to improved targeting and tissue sample quality.

[0023] Figure 7 shows a comparison of the use of a standard of care (SOC) biopsy needle set with a notched needle, such as that in Figures 5A and 5B, and a needle set using the biopsy needle 100 described in this patent specification. The images show the penetration of a needle set into a ballistic gel in which regularly spaced vertical lines of dye have been injected into the gel. In both cases, the needle set is attached to a well-known biopsy instrument, i.e., a Bard Magnum Gun, with a spring-loaded needle and cutting cannula. The dark upper and lower lines are dye and are initially nearly vertical. The top panel of each column of images shows the initial stage of penetration of the gel with the biopsy needle and cutting cannula surrounding the needle notch (images in the left-hand column) and the cradle (images in the right-hand column). At this stage, the cutting cannula covers the notch or cradle of the biopsy needle, as is typically done when using semi-automated and automated biopsy instruments. The top left image shows penetration using the SOC needle set, and the top right image shows penetration by the needle 100 and cannula 108. As shown, the dye line is somewhat more displaced in the left image, indicating more tissue displacement and disruption with the SOC needle set. The images in the second row from the top show a larger difference in performance as the needle is launched distally relative to the cannula. With the SOC needle set, the needle begins to bend upward, while needle 100 does not have this upward bend, indicating better targeting. The third and fourth rows of images from the top show a more dramatic difference, with the SOC needle bending much more, indicating poor targeting of the target tissue, while needle 100 follows a straight path. The bottom row of images shows the stage when the cutting cannula is launched distally over the tissue notch or cradle. The difference is very noticeable, with the gel being much more disrupted and displaced with the SOC needle set than with the needle 100 and cannula 108 set. Some of the reason for this difference may be that driving the cannula over the bent needle in the SOC set pulls the gel downward from its initial position. This does not occur with needles because the needle 100 did not undergo such bending and therefore driving the cannula 108 on the needle 100 did not pull the gel down or otherwise cause gel displacement as in the image on the left.

[0024] The better targeting of needle 100 is due in part to the configuration of cradle 104 with its teeth 104b and 104c relative to cannula 108. As described in detail with respect to similar structures in the parent patent applications incorporated by reference above, the outer surfaces of the teeth extending up from the underside and cradle floor of cradle 104 abut the inner surface of cannula 108 as cradle 104 moves distally from cannula 108 and into the tissue of interest, thereby keeping the portion of needle 100 protruding distally from cannula 108 straighter and keeping the portion of cradle 104 inside cannula 108 centered within the cannula.

[0025] Further improvement in targeting is believed to result from forming the distal end of tip 102 as a laterally extending cutting edge 102a rather than as a point as in the SOC needles of Figures 5B and 6B. Experiments with tissue as shown in Figure 7 showed better targeting, believed to be facilitated by less vertical displacement of the tissue as needle 100 moves distally into the tissue, compared to needle tips as in Figures 5B and 6B, with the cutting point at the level of the needle's bottom and the upper facet starting from that point.

[0026] As described in detail in the parent application, which is incorporated by reference, better quality tissue samples are obtained using needles with cradles such as cradle 104 compared to SOC needles with open notches. Expert declarations submitted in parent application Ser. No. 17 / 082,387 (to be issued as Patent No. 11,903,569) confirm that in patient testing, needles with teeth performed significantly and unexpectedly better than SOC needles with open notches. The better performance includes obtaining tissue samples with larger cross-sections, larger volumes, and less distortion, such as stretching, degradation, or bunching, compared to SOC needles.

[0027] Figure 8 shows a front view of the tip 102 of the biopsy needle 100 described above. With reference to the notation in Figure 2, the front view in Figure 8 shows (i) the level of the bottom of the needle 100 at B, (ii) the level of the cutting edge 102a at E (cutting edge 102a can include right portion 102a1 and left portion 102a2), (iii) the level of the cradle floor 104a at D, (iv) the central axis A along which teeth 104b and 104c extend, and (v) the level of the top of the needle 100 at C. In particular, the cutting edge 102a at level E is spaced from the bottom of the needle at level B but is below the level of the cradle floor at D, which is itself below the central axis A.

[0028] While the above describes embodiments in some detail for clarity, it will be apparent that certain changes and modifications can be made without departing from the principles thereof. There may be alternative ways of implementing both the process and apparatus described herein. As a non-limiting example, the distal cutting edge 102a may be shaped so that it is straight rather than V-shaped in top view, or may have another shape in top view, such as a laterally extending straight or curved line. Therefore, the present embodiments should be considered illustrative and not limiting, and the working bodies described herein should not be limited to the details given herein, but may be modified within the scope of the appended claims and their equivalents. [Explanation of symbols]

[0029] 100 Biopsy Needles 102 Needle Tip 102a Distal Cutting Edge, Level Cutting Edge 102a1 Left portion, right portion, distal cutting edge 102a2 Right portion, left portion, distal cutting edge 102b Upper facet, lower facet 102c Lower Facet 102c1 Lower left facet 102c2 Lower right facet 102d Vertical Edge 104 Cradle 104a Cradle Floor 104b Teeth, row of teeth 104c Teeth, row of teeth 106 Shaft 108 Hollow Cutting Cannula 108a sharp distal end 500 Standard of Care Biopsy Needles, Standard of Care Needles 502 needle tip 502a Side facet, point 502b Side Facet 502c upper facet 504 Notched part, notch 504a Notch 508 Cutting Cannula A center axis B Bottom range, level C Top range, level D level E level F cross section G cross section K-level

Claims

1. 1. A biopsy needle set comprising a biopsy needle (100), the biopsy needle extending along a central axis (A) at an intermediate level between a top region (C) and a bottom region (B) of the biopsy needle, the biopsy needle comprising: a tip (102), a cradle (104) proximal to the tip, and a shaft (106) proximal to the cradle; the cradle is between the central axis and the bottom extent of the biopsy needle and comprises an upwardly facing floor (104a) having sides flanking the central axis, and rows of teeth (104b, 104c) extending upward from each side of the floor to a level approximating the level of the central axis; The teeth in each row are spaced apart from one another along the central axis.

2. 2. The biopsy needle set of claim 1, wherein the teeth are axially staggered such that some cross sections of the cradle (G) include only one tooth of the row and some (F) include no teeth.

3. 2. The biopsy needle set of claim 1, wherein the tip comprises an upper facet (102b) and a lower facet (102c1, 102c2) at a distal end of the tip that converge toward each other distally to form a laterally extending distal cutting edge (102a, 102a1, 102a2).

4. 4. The biopsy needle set of claim 3, wherein the laterally extending distal cutting edge is spaced from the bottom extent of the biopsy needle but below the level of the floor of the cradle.

5. 2. The biopsy needle set of claim 1, wherein the distal cutting edge is at a level spaced apart from the bottom extent of the biopsy needle by a distance approaching one-third of the distance from the bottom extent of the biopsy needle to the level of the floor of the cradle.

6. 10. The biopsy needle set of claim 1, wherein the distal cutting edge is at a level spaced 15,000 inches (0.00381 cm) ±5,000 inches (0.00127 cm) from the bottom extent of the biopsy needle.

7. The biopsy needle set of claim 1 , wherein the upper and lower facets comprise two side-by-side lower facets (102a1 and 102a2).

8. 2. The biopsy needle set of claim 1, wherein the lower facet comprises two lower facets that converge to an upper and lower edge (102d) below the laterally extending cutting edge and extending proximally from the laterally extending cutting edge.

9. The biopsy needle set of claim 1 , wherein the upper and lower facets comprise two lower facets that are each shorter along the central axis than the upper facet.

10. 2. The biopsy needle set of claim 1, wherein the tines are arranged such that some cross sections of the cradle include only one of the tines and some include none of the tines.

11. 10. The biopsy needle set of claim 1, wherein the laterally extending distal cutting edge is V-shaped in top view.

12. 2. The biopsy needle set of claim 1, wherein the laterally extending distal cutting edge comprises two portions (102a1, 102a2) each extending along a respective straight line.

13. 10. The biopsy needle set of claim 1, wherein the laterally extending distal cutting edge extends along a single straight line.

14. The biopsy needle set of claim 1 , wherein the laterally extending distal cutting edge extends along at least one curve.

15. 10. The biopsy needle set of claim 1, further comprising a hollow cutting cannula configured to slide distally and proximally over the biopsy needle along the central axis such that an outer bottom surface of the cradle and outer surfaces of the tines abut an inner surface of the hollow cutting cannula to hold the biopsy needle centered in the hollow cutting cannula to resist bending of the biopsy needle when a portion of the cradle extends distally from the hollow cutting cannula.

Images