A biopsy system comprising a core collector that remains radially centrally positioned within the outer cannula during tissue sample cutting.

Abstract

To provide a biopsy instrument and method that solve prior art drawbacks.SOLUTION: A core collector is shaped as a crescent in cross-section and has lateral sides formed into axially extending rows of axially spaced teeth. The arc angle of the crescent shape is sufficient to keep the core collector radially centered in a cannula by having the crescent's lateral sides bear against the inside of the cannula. The set of the core collector and the cannula can be used in a known biopsy system to replace the known cannula and core collector or can be used in a new core biopsy instrument.SELECTED DRAWING: Figure 1A

Description

Technical Field

[0001] This patent specification relates to a medical device for collecting a soft tissue sample containing a prostate tissue sample. Some embodiments relate to a core collector that remains centered radially relative to an outer cannula that cuts the tissue sample, and others include an apparatus for driving the outer cannula and the core collector for sampling the tissue, and relate to alternative core collector configurations.

[0002] This application claims priority to provisional patent application serial number 62 / 955,559, filed February 4, 2020, and incorporates the content of the provisional application by reference.

Background Art

[0003] When suspicious tissue is found in a patient's prostate or another area through imaging methods such as ultrasound, MRI, or X-ray imaging, or through manual examination, it may be desirable to perform a biopsy procedure to remove one or more samples of the tissue to help determine whether the tissue contains cancer cells or other cells of interest, or to obtain other information. Biopsies can be performed using open or percutaneous methods. In the case of prostate tissue, a core needle device is typically used, which is inserted into the prostate transrectally (TRUS) or transperineally (TPUS). There are complex prostate sampling devices that require two or more people for the procedure. There are also simpler devices, some of which can be discarded after use in one patient. U.S. Patents 5,546,957, 5,526,822, and 10,463,350, and U.S. Published Patent Application 2016 / 0166331 describe examples of biopsy devices. The contents of the aforementioned patents and published applications are incorporated herein by reference. The core biopsy device called the Bard Magnum appears to be commercially available from BD Bard in Tempe, Arizona, and similar devices are also available from other manufacturers.

[0004] Typically, known conventional core biopsy instruments use a set of outer cannulas surrounding a core collector. Initially, the core collector is inside the cannula so that only its sharp tip protrudes from the distal end. In this configuration, the cannula and core collector are inserted together into the tissue until the sharp tip is in or inside the area of ​​interest. The core collector then protrudes distally into the tissue, and the tissue protrudes into a notch proximal to the sharp tip. A mere moment later, the cannula protrudes distally to its initial position relative to the core collector. The cannula has a sharp distal end, which, in this distal movement, cuts some of the tissue that has entered the notch. The cannula and core collector can be withdrawn from the tissue, and the sample is removed after moving the cannula and core collector axially relative to each other to expose the notch.

[0005] Figure 17A shows the distal portion of a typical commercially available set consisting of a cannula 1710 with a sharp distal end 1710a and a core collector 1712 with a sharp distal tip 1712a and a notch 1712b. Figure 17B shows a complete commercially available set, though not in more detail, in which an engaging element 1712c is fixed to the proximal end of the core collector 1712. This element, or a similar engaging element, engages with the respective drive mechanisms, such as a spring-loaded mechanism, to first eject the core collector distally, and then the cannula distally. Figure 18 illustrates several relative positions of the cannula 1710 and core collector 1712 in the vicinity of the tissue to be harvested 1810. The first figure shows the initial position, in which the sharp distal end 1712a of the core collector 1712 protrudes from the cannula 1710, and the notch 1712b is inside the cannula 1710. In this example, tissue 1810 includes denser tissue such as the capsule 1810a and calcification 1810b. The following figure shows the midpoint of the distal movement of the core collector 1712. Notably, here the denser tissue deflects the core collector upward and bends the notch 1712b, preventing penetration into the denser tissue. The following figure shows the core collector 1712 fully extended distally from the cannula 1710. At this relative position of the cannula 1710 and core collector 1712, some tissue (not shown) enters the notch 1712b from above. The following figure shows the lateral cannula 1710 advanced partway distally across the notch 1712b of the core collector 1712, cutting some of the tissue into the notch 1712b. The last figure shows the final position of the cannula 1710 relative to the core collector 1712, in which case the distal movement of the cannula 1710 cuts the tissue within the notch 1712b. However, as shown, two undesirable effects occur due to the gap between the bottom surface of the cannula 1710 and the notch 1712b.One possibility is that the reduced space between the upper side of notch 1712b and the cannula 1710 during most of the distal movement of the cannula 1710 across notch 1712b may stretch and / or clump together or fragment the tissue sample, thereby reducing its value as a representative sample of the original tissue. Another possibility is that the volume of tissue recovered may be substantially smaller than the initial volume of the space between the inside of the cannula 1710 and the upper surface of notch 1712b as seen in the first figure. Figure 19 illustrates this reduction in sample volume, with the left-hand figure showing the potential volume 1910 for the tissue between the inside of the cannula 1710 and the upper surface of the notch 1712b, and the right-hand figure showing the volume 1912 reduced due to the gap between the lower portion of the cannula 1710 and the underside of the notch 1712b, and the upward displacement of the core collector 1712 in the notch 1712b, as described above. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] U.S. Publication No. 5,546,957 [Patent Document 2] U.S. Publication No. 5,526,822 [Patent Document 3] U.S. Publication No. 10,463,350 [Patent Document 4] U.S. Patent Publication No. 2016 / 0166331 [Overview of the project] [Problems that the invention aims to solve]

[0007] This patent specification relates to a biopsy instrument that eliminates some of the shortcomings of known biopsy instruments and provides other advantages as described in detail below. [Means for solving the problem]

[0008] A biopsy instrument based on several embodiments comprises a tubular cannula extending along a longitudinal axis and having an inner wall and a sharp distal end; a core collector fitted inside the cannula for relative movement with the cannula along the axis and having a sharp distal tip and a cradle portion extending proximal to the sharp tip along the axis, wherein (a) the cradle portion of the core collector has a convex bottom surface and a concave bottom surface and the side walls form the cradle portion; and (b) the side walls withstand the inner wall of the cannula when inside the cannula, thereby preventing the core collector from entering the cannula. (c) The core collector is configured to maintain cardiac positioning and to maintain the bottom surface of the core collector against the inner wall of the cannula, and (d) the side wall of the core collector has a plurality of rows of teeth, each of which teeth are spaced apart from each other along the axis, and (d) the teeth are configured to engage with the tissue that has entered the cradle while the core collector is protruding distally from the cannula, and to prevent the tissue from being distorted when the cannula cuts the tissue sample from the surrounding tissue as the cannula moves distally on the cradle, thereby maintaining the structural integrity of the tissue sample along the axis.

[0009] According to several embodiments, the biopsy instrument further includes one or more of the following features: (1) the teeth are shaped to engage with the surrounding tissue so that the tissue sample is not compressed and / or stretched along the axis when the cannula moves along the cradle along the axis to cut the sample from the surrounding tissue; (2) each tooth of the side wall is offset relative to the teeth of other side walls such that some cross-sections include teeth of both rows, some include only one tooth of one of the multiple rows, and some include only one tooth of another of the multiple rows; and (3) in each of the cross-sections, the vertical distance between the top of the inner surface of the cannula and one tooth does not exceed half the diameter of the inner wall, thereby providing a cutting action when the cannula moves along the cradle, which facilitates maintaining the structural integrity of the sample compared to its integrity before being cut from the surrounding tissue.

[0010] According to several embodiments, the biopsy instrument comprises a tubular cannula extending along a longitudinal axis and having an inner wall and a sharp distal end; a core collector fitted into the cannula to move relative to the cannula along the axis and having a sharp distal tip and a cradle portion extending proximal along the axis from the sharp tip, wherein (a) the cradle portion of the core collector extends along the axis and has side walls forming the cradle portion and has a convex bottom and a concave upper surface; and (b) the side walls of the core collector extend above the intermediate surface of the inner wall that coincides with the axis and has a plurality of teeth (c) The cradle has a plurality of rows, wherein the plurality of teeth of each of the plurality of rows are spaced apart from each other along the axis, and several cross-sections of the cradle are offset such that some include teeth of both rows, some include only one tooth of one of the plurality of rows, and some include only one tooth of the other of the plurality of rows, and (c) the plurality of teeth are configured to engage with the tissue that enters the cradle while the core collector is protruding distally from the cannula, and to maintain the structural integrity of the tissue sample by preventing the tissue from being distorted as the cannula moves along the cradle to cut the tissue sample from the surrounding tissue.

[0011] According to several embodiments, the instrument described in the preceding paragraph further has one or more of the following features: (1) the plurality of teeth are configured to maintain the structural integrity of the tissue sample along the axis; (2) the plurality of teeth are configured to maintain the structural integrity of the tissue sample in a direction transverse to the axis; and (3) the plurality of teeth are configured to maintain the structural integrity of the tissue sample both along the axis and transverse to the axis.

[0012] According to several embodiments, the biopsy instrument comprises an axially extending tubular cannula having an inner wall and a sharp distal end, and an axially extending core collector having a sharp distal tip and a proximal portion extending proximally from the sharp tip, the core collector being shaped to fit into the cannula for relative movement between the cannula and the core collector, wherein the proximal portion of the core collector has a concave upper surface, a convex bottom and a lateral tip in some but not all of its cross-section. The core collector has a crescent shape, the crescent shape extending over a sufficiently large arc angle, the lateral tip contacts the inner wall, thereby maintaining the proximal portion radially centered within the cannula and the bottom contacting the inner wall of the cannula, thereby providing an open space for the tissue sample, and each of the lateral tips of the crescent-shaped proximal portion of the core collector has a row of multiple teeth spaced apart from each other in the axial direction.

[0013] According to some embodiments, the instrument of the preceding paragraph further includes one or more of the following features: (1) the bottom of the proximal portion of the core collector extends beyond half the circumference of the inner wall of the cannula; (2) the multiple teeth are smoothly polished; (3) the proximal portion of the core collector is machined from a solid rod; and (4) the instrument further includes a drive mechanism that engages with the cannula and the proximal end of the core collector to selectively drive the cannula distally so that the proximal portion of the core collector protrudes distally from the cannula by a selected distance, and then the sharp distal end of the cannula advances toward the sharp distal end of the core collector to cut a tissue sample extending into the open space.

[0014] According to several embodiments, the method includes providing an axially extending core collector having a crescent shape in at least some cross-sections and having two rows of multiple teeth formed on the lateral side of the crescent shape, with the multiple teeth of each row being axially separated from each other, and a cannula shaped to surround the core collector for relative motion between the core collector and the cannula, wherein the crescent shape extends over an arc angle sufficient to maintain the core collector radially centered within the cannula by the lateral side abutting against the inner wall of the cannula, and introducing the cannula and core collector into tissue and driving the core collector distally from the cannula and within the tissue for a selected length, thereafter driving the cannula distally over the core collector to cut the tissue sample while maintaining the core collector radially centered within the cannula, and removing the tissue sample collected in the open space between the cannula and the crescent-shaped core collector.

[0015] According to several embodiments, the method further includes one or more of the following steps: (1) driving the core collector, which contains the tissue sample inside, in a position aligned with a cartridge that is detachably fixed to a handle supporting the cannula and core collector, and which detachably latches the core collector to the cartridge, and removing the cartridge to which the core collector is latched from the handle; and (2) removing a structurally integrated tissue sample from the core collector after it has been removed from the handle.

[0016] According to several embodiments, the biopsy instrument comprises an axially extending core collector having a crescent shape in at least some cross-sections and comprising a convex lower surface and a concave upper surface, and comprising two axially extending rows of multiple teeth formed on the lateral side of the crescent shape, with multiple teeth in each row being axially separated from each other, and a tubular cannula having an inner wall and a sharp distal end, wherein (a) the cannula is positioned such that a selected length of the core collector extends distally from the cannula to a first relative position (b) The cannula is configured to receive the core collector in relative motion between the first position and a second position which is moved distally relative to and over the core collector, and (b) the crescent shape of the core collector extends over an arc angle sufficient to maintain the core collector radially centered within the cannula, due to the lateral side of the core collector contacting the inner wall of the cannula so that the convex bottom of the core collector does not move away from the inside of the cannula due to a force acting on the core collector transversely with respect to the axial length of the core collector.

[0017] In some embodiments, the apparatus of the preceding paragraph further includes one or more of the following features: (1) the arc extends over an angle that is at least a semicircle but less than a perfect circle, and (2) the arc extends over an angle that is close to a semicircle. [Brief explanation of the drawing]

[0018] [Figure 1A] Partial perspective view of the cannula and core collector. [Figure 1B] A partial side view of the core collector. [Figure 1C] Cross-sectional views of core collectors based on several examples. [Figure 1D]Schematic diagram illustrating that a core collector based on several embodiments maintains a centered position within a cannula as compared to what does not happen with a known combination of a core collector and a cannula. [Figure 1E] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1F] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1G] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1H] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1I] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1J] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1K] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1L] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 1M] Schematic diagram illustrating important advantages of a core collector and a cannula based on several embodiments as compared to a known combination of a core collector and a cannula. [Figure 2A] Partial schematic side view of a core biopsy instrument. [Figure 2B]Side view of the core collector. [Figure 2C] Perspective views of a core collector based on several embodiments. [Figure 2D] Perspective views of a core collector based on several embodiments. [Figure 2E] Perspective views of a core collector based on several embodiments. [Figure 3] A partial schematic side view showing a cartridge detachably fixed to a handle based on several embodiments. [Figure 4] A partial schematic side view showing a core collector advanced into the cannula based on several embodiments. [Figure 5] A partial schematic side view showing a core collector advanced distally from the cannula, based on several embodiments. [Figure 6] A partial schematic side view showing a cannula advanced distally on a core collector, based on several embodiments. [Figure 7] An enlarged schematic diagram showing the side view of the distal portion of the core collector and a cross-section of a cannula partially advanced on the core collector, based on several embodiments. [Figure 8] Perspective views of parts of the cannula and core collector shown in Figure 7, based on several embodiments. [Figure 9] Perspective views of cartridges based on several embodiments. [Figure 10] Enlarged perspective view of a cartridge based on several embodiments. [Figure 11] Side view of the proximal portion of the core collector and the interlocked drive rod, based on several embodiments. [Figure 12] Perspective view of the drive rod interlocking with the proximal portion of the core collector, based on several embodiments. [Figure 13A] Side view of the distal portion of a drive rod based on several embodiments. [Figure 13B] Plan view of the distal portion of a drive rod based on several embodiments. [Figure 13C] Perspective view of the distal portion of a drive rod based on several embodiments. [Figure 13D] Perspective view of the distal portion of a drive rod based on several embodiments. [Figure 14A] Cross-sectional view along plane D in Figure 4. [Figure 14B] Cross-sectional view along plane E in Figure 4. [Figure 14C] Cross-sectional view along plane F in Figure 7. [Figure 14D] A cross-sectional view along plane G in Figure 7. [Figure 14E] Cross-sectional view along plane H in Figure 7. [Figure 15] Perspective views of core biopsy instruments based on several examples. [Figure 16] (A) to (D) are schematic diagrams illustrating certain stages in the operation of a spring-loaded cannula and a spring-loaded core collector based on several embodiments. [Figure 17] (A) is a perspective view of the distal portion of a typical known set of core collector and lateral cannula with lateral tissue notch capture, and (B) is a schematic diagram showing the entire set. [Figure 18] A schematic diagram showing the firing sequence of a typical known core biopsy instrument. [Figure 19] Cross-sectional view of a typical known core collector notch at different relative axial positions of the cannula and core collector. [Modes for carrying out the invention]

[0019] The following provides a detailed description of several preferred embodiments. While several embodiments are described, the novel features described herein are not limited to any one embodiment or combination thereof, but encompass numerous alternatives, modifications, and equivalents. Furthermore, for the sake of complete understanding, numerous specific details are described below, although some embodiments can be implemented without some or all of these details. Additionally, for the sake of clarity, certain technical matters known in the related art are not described in detail to avoid unnecessarily obscuring the novel features described herein. It is evident that one or more individual features of the specific embodiments described herein can be used in combination with or in conjunction with features of other described embodiments. Furthermore, similar reference numbers and symbols in the various drawings represent similar elements.

[0020] Figure 1A illustrates the distal portions of the outer cannula 10 and core collector 12 in partial perspective views based on several embodiments. They differ considerably from known core collectors of the type shown in Figures 17A-B. The proximal portions of the cannula 10 and core collector 12 are not shown in this figure, but as is known in the art, they typically include attachments or fixtures for engaging with a drive mechanism for successively launching the core collector and cannula distally into the tissue, for example, in the form of an engaging element 1712c shown in Figure 17B. The core collector is typically longer than the cannula by at least the axial length of the core collector portion extending distally from the cannula, as seen in Figure 1A. In particular, the core collector 12 has an axially extending and curved bottom trough 12b defined as the space between two parallel, axially extending rows of multiple teeth 12c and 12d. Multiple teeth 12c are axially separated from each other by notches 12e. The distal teeth 12c are similarly separated from the tip portion 12a, and the proximal teeth 12c are similarly separated from the solid portion 12f of the core collector 12. Multiple teeth 12d are similarly axially separated from each other by notches 12g, and the distal and proximal teeth 12d are similarly separated from the tip portion 12a and the solid portion 12f, respectively.

[0021] Figure 1B shows the position of the core collector 12 and sections AA, BB, and CC, and Figure 1C shows their cross-sections. The left side of Figure 1C shows the portion where section AA intersects with both one tooth 12c and one tooth 12d, showing that the core collector 12 has a crescent shape and that the trough 12e is on the concave side of the shape. Teeth 12c and 12d are formed by the lateral tip of the crescent shape. In this cross-section, the crescent shape has a concave upper surface, a convex bottom and a lateral tip, and the crescent shape extends over a sufficiently large arc angle to maintain the core collector in a radially centered position within the cannula and to maintain the bottom of the core collector in contact with the inner wall of the cannula by the lateral tip contacting the inner wall of the cannula. The crescent shape preferably extends over an arc angle of approximately 180 degrees, although the angle can be somewhat larger or smaller. This shape provides an open space above the concave side of the crescent to hold the sample tissue and prevents the bottom of the core collector from rising and reducing the open space 12e.

[0022] In the center of Figure 1C, cross section BB is through the notch or gap 12g between tooth 12c and two adjacent teeth 12d, and in the right side of Figure 1C, cross section CC is through the notch or gap 12e between tooth 12d and two adjacent teeth 12c. It should be noted that, in the axial direction, each tooth 12c overlaps somewhat with tooth 12d. The core collector 12 can be machined from a solid rod made of a material such as 304SS (stainless steel). The teeth, or at least the tooth ends, are preferably polished smoothly to preserve the tissue sample with as little damage as possible and to facilitate the release of the tissue sample after the cannula 10 and core collector 12 have been withdrawn from the patient.

[0023] Figure 1D illustrates a significant advantage of the core collector 12's morphology. The left side of Figure 1D shows the potential space 12e for tissue sampling between the upper surface of the trough 12b and the inside of the cannula 10. The right side of Figure 1D shows that this potential space for tissue sampling remains nearly the same even when the core collector 12 is maximally deflected, and that only a small gap 14 can exist between the bottom of the core collector 12 and the inside of the cannula 10. This is because the teeth 12c and 12d are in contact with the portion of the cannula 10 where the spatial dimension decreases above the crescent shape, and therefore cannot go any further upward within the cannula 10. This is a striking contrast to the known cannula and core collector units shown in Figure 17. As a result, it is possible to extract tissue samples with a larger cross-section using a cannula of the same diameter compared to known instruments, and these samples have greater integrity and maintain a shape closer to their original shape in the surrounding tissue. Therefore, these samples can have improved clinical values ​​compared to samples extracted with known cannulas and core collectors of the type shown in Figure 17. In a test comparing the performance of cannula 10 and core collector 12 with commercially available cannulas and core collectors (from Bard Magnum Biopsy Gun) as shown in Figure 17, samples obtained using core collector 12 were larger, more consistent, and maintained better integrity.

[0024] The cannula 10 and core collector 12 can be used in place of the cannula and core collector in a known biopsy device, such as the Bird Magnum instrument described above, by using an appropriate attachment or mounting device on the proximal end of the cannula and core collector that engage with the drive mechanism of the known biopsy device. Alternatively, the core collector 12 can be used in place of the known core collector in a known device while the known cannula remains as is. Alternatively, the cannula 10 and core collector 12 can be used in a biopsy device as described below. When used in a device as described below, the core collector 12 replaces the core collector 110 described below.

[0025] As described above, maintaining the core collector centrally positioned within the cannula offers significant advantages compared to known biopsy devices. Some of these advantages are highlighted in Figures 1E to 1M below.

[0026] Figures 1E to 1G illustrate the interaction between a known biopsy device and conceptual tissue fibers, and Figures 1H to 1I illustrate a similar interaction using a core collector based on embodiments such as Figure 1A. Figure 1E shows the sharp tip 1712a of the core collector 1712 protruding distally from the cannula 1710 (see Figure 17A), passing over one conceptual fiber of tissue 200 and below the next fiber 200. At this stage, the figure is similar to that of Figure 1H, where the tip 12a of the core collector 12 protrudes distally from the cannula 10, passing under one conceptual fiber or strip of tissue 200 and above the next fiber 200. The differences from the known device become even clearer by comparing Figure 1F with Figure 1I. In Figure 1F, several conceptual fibers of the tissue are within the notches 1712b of the core collector 1712, but are not held in place by the core collector. In contrast, in Figure 1I, all fibers 200 are located in the space between two adjacent teeth 12c or two adjacent teeth 12d of the core collector 12, and are therefore not deformed along the longitudinal axis of the core collector 12. Comparing Figure 1G with Figure 1J, as seen in Figure 1G, when the known core collector is fully extended distally from the cannula 1710, all fibers 200 within the notch 112a are able to slide axially, whereas in Figure 1J, each of the fibers 200 in equivalent positions is constrained from axial deformation by the teeth 12c and 12d.

[0027] Figures 1I and 1K illustrate the specific advantages of constraining the conceptual tissue fibers 200 from distortion due to movement compared to allowing the tissue fibers 200 to move along the notch 1712b as the cannula 1710 moves distally over the core collector 1712. Figures 1I and 1K show a known cannula 1710 at the midpoint of distal movement over the core collector 172 when the movement of the cannula 1710 cleaves the tissue that has entered the notch 1712b. As illustrated, the distal end of the cannula 1710 tends to press the conceptual tissue fibers 200 distally when they are cleaved, resulting in the undesirable consequence of distorting the tissue sample held within the cannula 1710. Furthermore, since the distal portion of the core collector 1712 may bend upward (in the orientation seen in Figures 1I and 1K), the space for the tissue sample within the cannula 1710 is reduced. For these two reasons, tissue samples may be distorted in both the axial and radial directions, reducing their clinical value.

[0028] In contrast, Figure 1M illustrates how the novel approach of the core collector 12 maintains the integrity of the tissue sample. Since the tissue fibers 200 are prevented from axially moving relative to the core collector 12, the distal cut end of the cannula 10 cuts the fibers essentially as if they were in living tissue, reducing axial distortion. Furthermore, as described above (see Figures 1C and 1D), the distal portion of the core collector 12 is prevented from bending, and the free space 12e inside the cannula 10 maintains its volume, thus maintaining the radial distortion of the tissue sample inside the cannula 10. As a result, with known core collector and cannula combinations, the tissue sample may be substantially different from what it would be if it were in living tissue (it may be stretched, its diameter may change at its location within the sample, or it may break in several places), whereas with the novel approach described in this patent specification, the integrity of the tissue can be substantially maintained, and the clinical value of the tissue sample can be significantly improved.

[0029] Figure 2A shows a biopsy instrument comprising a cannula and a core collector which can be as shown in Figures 1A-1D or alternatively as shown in Figure 2B. The instrument has a housing or handle 102, which is only schematically shown in Figure 2A. As shown in Figure 2A, a cylindrical cannula 104 extends distally and terminates at a sharp distal end 104a formed by a cutting cannula 104 along a plane angled with respect to the longitudinal central axis A. The cannula 104 has a proximal end held within a support block 104b, which moves within a channel inside the handle 102 or along one or more guide rods (not shown) for both distal and proximal movement along axis A. A holder block 106 is fixed within the handle 102 and is configured to detachably receive a cartridge 110 that holds the core collector 110. The drive rod 112 is mounted in a channel (not shown) within a holder 106 that extends along the central axis A, and the proximal portion 112a of the drive rod 112 can extend proximal from the proximal end of the handle 102, and can be terminated proximal by a handle or knob (not shown) for manually moving the rod 112 distally and proximal relative to the handle 102.

[0030] Figure 2B is a side view of the core collector 110, and Figures 2C-2E are different perspective views of the core collector based on several embodiments. The core collector 110 has a sharp distal end 110a which fits into a plane angled with respect to axis A and is preferably closed off along axis A through its distal end. Two rows of teeth 110b1 and 110b2 extend proximal from the distal end 110a of the core collector 110. In a cross section perpendicular to axis A, the portion of the core collector 110 having multiple rows of teeth is substantially semicircular in shape, defining a trough 111 (Figures 2B-2E) from which teeth 110a and 110b extend along a side wall. These teeth have proximal lateral portions that can be tilted proximal and sharpened to perform important functions further described below. The cylindrical portion 110c of the core collector 110 is located proximal to the two rows of teeth and has a side hole 110d that performs a function to be described in more detail below. The notch 110e is located proximal to the cylindrical portion 11d and is preferably an arc extending over less than 180 degrees in a cross section perpendicular to axis A. The proximal end 110f of the core collector 110 is also an arc, but preferably extends over an even larger angle exceeding 180 degrees, so that the notch 110e terminates at a raised portion formed distally and proximally by portions 110c and 110f.

[0031] Figures 3-6 are partially side and partially cross-sectional views of the core biopsy instrument 100 illustrating its operation in several embodiments. For clarity, the handle 102 is omitted from these figures, but it is present when the instrument is in use. Figure 3 shows the initial state, in which the cartridge 108 is mounted in the holder 106, and therefore the core collector 110 is in a channel within the holder 106 and held in place, as will be described in more detail below, and interlocked with the distal end of the drive rod 112. Figure 4 shows the state in which the drive rod 112 presses the core collector 110 distally, with its sharp distal end protruding distally from the cannula 104. For this purpose, the drive rod 112 can be manually pressed distally from the rear of the proximal portion of the handle 102. As will be described in more detail below, the surfaces into which the distal ends of the cannula 104 and the core collector 110 fit are angled in the opposite direction to the central axis A. The distal end 110a of the core collector 110 is fitted into the cannula 104 in a sliding manner, allowing tissue to enter the space between them. In this state, the physician inserts the cannula 104 and core collector 110 into the patient's tissue until the distal tip 110a of the core collector 110 is in a desired position relative to the tissue to be sampled, for example, just outside the patient's prostate, just inside the prostate, or into or just within the suspected lesion. This desired position can be determined based on clinical experience or intuition, or by using an imaging device such as an ultrasound probe that can be attached to the instrument 100 but does not need to be attached, or by using other imaging methods. Figure 5 shows the cannula 104 advanced distally relative to the cannula 104 so that all or at least some of the two rows of teeth are distal to the distal tip of the cannula 104.To this end, the spring action is released to drive the rod 112 distally, and thus the drive rod 112 can be spring-loaded to push the core collector 110 out of the cannula 104 over a desired distance that can be set by an appropriate stopper (not shown) for the drive rod 104 within the handle 102, as will be described in more detail below. In this state, the core collector 110 enters the tissue to be sampled (not shown), and the tissue sample enters the trough 111. The angle of the surface that fits the sharp distal end 110a of the core collector 110 contributes to pushing the tissue into the trough 111. This is because driving the distal end 110a of the core collector 110 into the tissue compresses the tissue on the open side of the trough 111 (the downstream side as seen in Figure 5), and this compressed tissue tends to jump into the trough 111. Figure 6 shows the state immediately after the core collector 110 has advanced distally to the state shown in Figure 5 (preferably in less than 1 second). To reach the state shown in Figure 6, the cannula 104 is also preferably spring-loaded, and its spring action is released immediately after the spring action for the core collector 110 is released, driving the cannula 104 distally along the core collector 110. This distal movement of the cannula 104 cuts the tissue sample that has entered the trough 111 of the core collector 110 from the surrounding tissue. In this cutting action, the two rows of teeth help to prevent the tissue sample from clumping together or coming out of the trough 111, as will be described in more detail below. Subsequently, both the cannula 104 and core collector 110, located in their respective positions as shown in Figure 6, are manually pulled proximally by, for example, the holder block 106 holding the drive rod 112 and cannula 104, until the cannula 104 and core collector 110 are in their respective positions as shown in Figure 4, and then the drive rod 112 is pulled further proximally until it positions the core collector 110 as shown in Figure 3.Next, as will be further explained below, the cartridge 108 holding the core collector 110 (which contains the tissue sample) is manually pulled off from the handle 102, chemically treated, and sealed for, for example, delivery to a laboratory. It should be noted that the tissue sample remains in the cartridge 108 and is not affected by handling. The orientation of the tissue sample relative to the living tissue from which the tissue sample was extracted is preserved because the core collector remains in the cartridge 106, and since the distal end of the cartridge 106 is known, the laboratory will have a clear indication of which end of the tissue sample is distal and which is proximal.

[0032] Figure 7 is a partial side view of the distal portion of the core collector 110 and a cross-sectional view of the distal portion of the cannula 104, and Figure 8 is a perspective view of the same portion of the cannula 104 and core collector 110. As shown in Figure 7, the distal end 110a of the core collector 110 fits into a surface B that is inclined in one direction with respect to the central axis A, and the distal end 104a of the cannula 104 fits into a surface C that is inclined in the opposite direction with respect to the central axis A. As shown in Figures 7 and 8, the distal end 104a of the cannula 104 is sharpened by gradually reducing the thickness of its wall distally until it reaches the inner diameter of the cannula 104.

[0033] Figure 9 is a perspective view of the cartridge 108, and Figure 10 is a perspective view of a part of the cartridge from different viewpoints based on several embodiments. The cartridge 108 has a channel 108a extending along the central axis A, and the channel is sized to receive the core collector 110 in a sliding fit manner, but to allow the core collector to move distally and proximal within the channel. The proximal portion of the cartridge 108 has a cage 108b comprising an opening through which the core collector 110 passes, and two elastic pins 108c that are sandwiched within the hole 110d (Figures 2A-2D) of the core collector 110 when the core collector is in the cartridge 108 in the position shown in Figures 9 and 10. The pin 108c is sufficiently elastic, allowing the drive rod 112 to push the core collector 110 distally, thereby disengaging it from the pin 108c, and also allowing the drive rod 112 to pull the core collector 110 proximal to the position shown in Figures 9 and 10, where the pin 108c can re-grip the core collector and maintain it in place when the cartridge 108 is pulled out from the handle 102. The cartridge 108 is equipped with a cantilevered projection 108d, etc., which snaps securely into a corresponding projection or recess (not shown) on the handle 102.

[0034] Figure 11 is a side view showing the interlock between the drive rod 112 and the core collector 110, and Figure 12 is a perspective view of the proximal end of the core collector 110 and the distal end of the drive rod 112, based on several embodiments. The drive rod 112 has a thicker distal end 112b that fits into a smaller arc notch 110e of the core collector 110, and a thinner portion 112c immediately proximal that fits into a larger arc notch 110f of the core collector 110. In operation, when the cartridge 108 has not yet been inserted into the handle 102, the distal end of the drive rod 112 is in the position shown in Figure 2a. When the cartridge 108 is inserted into the position shown in Figure 3, the drive rod 112 and the core collector 110 are in the interlocked position shown in Figure 11. When the cartridge 108 is removed by pulling it out of the handle 102, the drive rod 112 remains in its designated position within the handle 102, and the core collector 110 is released from its interlock with the drive rod 112.

[0035] Figure 13A is a side view of the distal portion of the drive rod 112, Figure 13B is a top view, and Figures 13C and 13D are two different perspective views. Part 112c of the drive rod 112 has a thinner band on one side of the reinforcing rib 113, and part 112b has a wider arc and a thinner rib 115, all of which act to interlock with the core collector 110.

[0036] Figures 14A-14E show cross-sections of the core collector 110 inside the cannula 104 in their respective planes perpendicular to the central axis A. Figure 14A is a cross-section along plane D in Figure 4 and shows how the reinforcing rib 113 (Figures 13B-13D) fits into portion 110f (Figure 12) of the core collector 110 when surrounded by the cannula 104 as shown in Figure 12. Figure 14B is a cross-section along plane E in Figure 4 and shows how the rib 115 (Figures 13B-13D) fits into portion 110f (Figure 12) of the core collector 110 inside the cannula 104 as shown in Figure 12. Figure 14C shows a cross-section along plane F in Figure 7 and shows the teeth 110b2 on the right side (as shown in Figure 14C) that extend above the left side wall of the trough 111 of the core collector 110 in that cross-section. Figure 14D shows a cross-section along plane G in Figure 7, and in that cross-section, the tooth 110b1 on the left side (as shown in Figure 14D) extends above the right side wall of the trough 111 of the core collector 110. Figure 14E shows a cross-section along plane H in Figure 7, in which case both side walls of the trough 111 are present and at the same height, where no teeth are present.

[0037] It should be noted that, for example, as shown in Figures 7 and 8, the teeth in these two examples are offset from each other. In this case, in a cross-section perpendicular to the central axis A, tooth 110b1 is present but tooth 110b2 is not, and if tooth 110b2 is present, tooth 110b1 is not. This makes it possible to facilitate the entry and retention of tissue into the trough 111 compared to a trough that extends over an arc and lacks teeth, such as the arcs in Figures 14C and 14D.

[0038] Furthermore, as shown in Figure 8, for example, the distal portion of the tooth can be tilted proximally, and in some embodiments, the proximal portion of the tooth can also be tilted somewhat proximally. In other embodiments, it is not necessary for the proximal portion of the tooth to be tilted proximally, or it is possible to tilt it in a different direction.

[0039] It should be noted that the teeth can be cut to have sharp edges on their proximal sides. Inclining the distal sides of the teeth reduces the portion of the trough 111 sidewall occupied by the teeth, thus facilitating the entry of tissue into the trough. Inclining the proximal sides of the teeth proximal and / or forming them with sharp edges facilitates the cutting action of the tissue sample in the trough 111 as the cannula 104 moves distally along the core collector 110.

[0040] Figure 15 is a perspective view of the core biopsy instrument 100, which shows an example of the handle 102, cannula 104, and the distal portion of the core collector 110 protruding distally from the cannula 104. Figure 15 shows a knob 101 on the proximal side of the handle, which is attached to the proximal end of the drive rod 112 and is used to manually pull the rod proximal and push it distal as needed. Furthermore, the knob 101 can be connected to a spring (not shown) in the handle 102, which is compressed when the knob 101 is pulled proximal until the spring is latched in a compressed state. When released, these springs drive the core collector 110 and cannula 104 distally as described above. Figure 15 also shows a manual switch 103, which, when pressed down, releases the spring from the latched state when it is compressed, driving the rod 112 distally. The spring that drives the cannula 104 distally can be released by a delay actuated by the forward movement of the rod 112 when the spring is released by operating the switch 103. In a specific and non-limiting example, the approximate dimensions of the handle 102 are 9.0 inches in length, 2.2 inches in width, and 1.3 inches in height. In this example, the cannula 104 protrudes approximately 6 inches distally from the handle 102.

[0041] In one operating mode, after the instrument 100 reaches the state shown in Figure 6, or after reaching the state in Figure 6 and returning to the state in Figure 4, the cannula 104 can be withdrawn from the patient. For another tissue sample, another tissue sample can be taken using the same instrument or an unused replica as described above. Alternatively, after reaching the state in Figure 6, or after returning to the state in Figure 4, the cannula 104 can be left in the patient or moved to a new orientation and / or depth in the patient, and only the core collector 110 can be retracted into the cartridge 108, the cartridge can be removed from the handle 102 and replaced with a new cartridge and a new core collector, and the procedure described above can be repeated to take a new tissue sample. The cartridge can be removed and replaced multiple times while the cannula 104 remains in the patient, thereby taking multiple tissue samples.

[0042] Figures 16A–16D illustrate a series of operations of a spring-loaded drive mechanism for a cannula 104 and core collector 110, based on several embodiments. For clarity, the handle 102 is omitted, but it surrounds the illustrated components except for the portion of the cannula 104 and core collector 110 protruding distally from the handle, and the portion of the drive rod 112 extending proximal to the handle. Figure 16A shows a spring 122, which is compressed and held between a block 120 attached to the handle 102 and a block 112d attached to the drive rod 112, and is movable distally and proximal along the central axis. A latch 118 holds the spring 122 in the compressed position shown in Figure 16A. Figure 16B shows the latch 118 rotated to release the spring 122, which is extended distally. The latch 118 can be released by operating a manual trigger, such as a trigger 103 (Figure 15). Figure 16C shows the spring 122 fully extended, in which position the block 112d is in contact with the proximal end of the latch 116 and rotates the latch 116 to the position shown in Figure 16C, releasing the spring 124 and driving the block 104b and cannula 104 distally. If it is desired to increase the time between when the core needle 110 reaches the end of its distal movement and when the cannula 104 begins its distal movement, a desired delay (not shown), such as a mechanical damper or buffer, can be introduced between the block 112d and the proximal end of the latch 116. Figure 16D shows the positions of the illustrated parts after the cannula 104 and core collector 110 have reached the end of their distal movement.

[0043] Although the above has been explained in some detail for clarity, it is clear that certain modifications and alterations can be made without deviating from the principle. Many alternative embodiments may exist to realize both the processes and apparatus described herein. Therefore, these embodiments should be interpreted as illustrative and not restrictive, and the substance of the gist described herein is not limited to the details given herein and can be modified within the scope of the claims and equivalents.

Claims

1. In biopsy instruments, A tubular cannula that extends along its longitudinal axis and has an inner wall and a sharp distal end, - A core collector fitted into the cannula to move relative along the axis and comprising a sharp distal tip and a cradle portion extending proximal from the sharp tip along the axis, It has, The cradle portion of the core collector has a convex bottom surface and a concave upper surface that has side walls forming the cradle portion. The side wall is configured to contact the side wall of the cannula when it is inside the cannula, thereby maintaining the core collector in a central position within the cannula and maintaining the bottom surface of the core collector in contact with the inner wall of the cannula. The side wall of the core collector has a plurality of rows of teeth, the teeth of the plurality of rows extending upward from the cradle portion separating the rows, and the teeth of each row are separated along the axis by notches extending downward to the level of the cradle portion. The teeth are configured to engage with the tissue that has entered the cradle portion while the core collector is protruding distally from the cannula, and to prevent the tissue from distorting when the cannula cuts the tissue sample from the surrounding tissue as the cannula moves distally on the cradle portion, thereby maintaining the structural integrity of the tissue sample along the axis. Biopsy equipment.

2. The biopsy instrument according to claim 1, wherein the teeth are configured to engage with the tissue to prevent the tissue sample from being compressed and / or stretched along the axis when the sample is cut from the surrounding tissue as the cannula moves along the axis on the cradle portion.

3. The biopsy instrument according to claim 2, wherein several cross-sections include teeth of both rows, several cross-sections include only one tooth of one of the multiple rows, and several cross-sections include only one tooth of the other of the multiple rows, the teeth of each of the multiple teeth of the side wall are offset relative to the multiple teeth of the other side wall, and in each of the cross-sections, the vertical distance between the upper part of the inner surface of the cannula and one tooth is less than approximately half the diameter of the inner wall, thereby causing a cutting action as the cannula moves over the cradle portion, which facilitates maintaining the structural integrity of the sample compared to its integrity before being cut from the surrounding tissue.

4. In biopsy instruments, A tubular cannula that extends along its longitudinal axis and has an inner wall and a sharp distal end, - A core collector fitted into the cannula for relative movement along the axis and comprising a sharp distal tip and a cradle portion extending proximal from the sharp tip along the axis, It has, The cradle portion of the core collector extends along the axis and has a concave upper surface that includes a convex bottom and side walls forming the cradle portion. The side wall of the core collector extends above the intermediate surface of the inner wall, which coincides with the axis, and has a plurality of rows of teeth, each of the plurality of teeth in the plurality of rows extends upward from the cradle portion separating the rows, and the teeth in each of the rows are separated from each other along the axis by notches that extend downward to the level of the cradle portion, and several cross-sections of the cradle portion are offset such that several cross-sections include multiple teeth in both rows, several cross-sections include only one tooth in one of the plurality of rows, and several cross-sections include only one tooth in the other of the plurality of rows. The aforementioned multiple teeth engage with the tissue that has entered the cradle portion while the core collector protrudes distally from the cannula, thereby preventing the tissue from being distorted as the cannula moves along the cradle portion and cuts the tissue sample from the surrounding tissue, and thereby maintaining the structural integrity of the tissue sample. Biopsy equipment.

5. The biopsy instrument according to claim 4, wherein the plurality of teeth are arranged in a manner that maintains the structural integrity of the tissue sample along the axis.

6. The biopsy instrument according to claim 4, wherein the plurality of teeth are configured to maintain the structural integrity of the tissue sample in a direction transverse to the axis.

7. The biopsy instrument according to claim 4, wherein the plurality of teeth are configured to maintain the structural integrity of the tissue sample both along the axis and in directions transverse to the axis.

8. A tubular cannula that extends axially and has an inner wall and a sharp distal end. An axially extending core collector comprising a sharp distal tip and a proximal portion extending proximal from the sharp tip and shaped to fit inside the cannula for relative movement with the cannula, It has, The proximal portion of the core collector has a crescent shape in some, though not all, cross-sections, comprising a concave upper surface, a convex bottom, and a lateral tip, and the crescent shape extends over a sufficiently large arc angle to maintain the proximal portion radially centered within the cannula and to cause the bottom to contact the inner wall of the cannula by the lateral tip contacting the inner wall, thereby providing an open space for the tissue sample. Each of the lateral tips of the crescent-shaped proximal portion of the core collector has a row of teeth that are axially separated from each other by a notch, and the notch extends downward to near the level of the upper surface of the core collector, separating the multiple rows of teeth. Biopsy equipment.

9. The biopsy instrument according to claim 8, wherein the bottom of the proximal portion of the core collector extends beyond half the circumference of the inner wall of the cannula.

10. The biopsy instrument according to claim 8, wherein the plurality of teeth are smoothly polished.

11. The biopsy instrument according to claim 8, wherein the proximal portion of the core collector is machined from a solid rod.

12. The biopsy instrument according to claim 8, further comprising a drive mechanism that first selectively drives the core collector distally so that the proximal portion of the core collector protrudes distally from the cannula by a selected distance, and then drives the cannula so that the sharp distal end of the cannula advances toward the sharp distal end of the core collector and drives the cannula to cut a tissue sample extending into the open space, the cannula and the proximal end of the core collector.

13. - A core collector that extends in the axial direction and has a crescent shape in at least some cross-sections and comprises a convex lower surface and a concave upper surface, The crescent shape has two rows of axially extending teeth formed on its lateral side, and the multiple teeth in each row are axially separated from each other by notches that extend downward to near the upper surface of the crescent shape. Core collector and A tubular cannula having an inner wall and a sharp distal end, It has, The cannula is configured to receive the core collector for relative movement between a first relative position where the selected length of the core collector extends distally from the cannula and a second position where the cannula moves distally relative to the core collector from the first position. The crescent shape of the core collector extends over an arc angle sufficient to maintain the core collector in a radially central position within the cannula, by preventing the convex lower side of the core collector from moving away from the inside of the cannula due to a force acting on the core collector in a direction transverse to the axial length of the core collector. Biopsy equipment.

14. The biopsy instrument according to claim 13, wherein the arc extends over an angle that is less than a perfect circle but at least a semicircle.

15. The biopsy instrument according to claim 13, wherein the arc extends over an angle that approaches a semicircle.

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