Core needle biopsy device

Abstract

The present disclosure provides a biopsy device for performing a soft tissue biopsy on any major organ through the venous system, and a method for using the biopsy device, the biopsy device including a housing, an elongated tube having a first proximal end and a first distal end, the first distal end being positioned at a biopsy site of a target organ, the first proximal end including a first locking mechanism coupled to the housing, and a biopsy needle having a second proximal end and a second distal end, the biopsy needle being positioned within the elongated tube to obtain a biopsy sample of the target organ at the biopsy site, the second proximal end of the biopsy needle including a second locking mechanism coupled to the housing.

Description

Technical Field

[0001] The present disclosure relates to a biopsy device, and more particularly, to a biopsy device for obtaining a biopsy sample of a target organ. In particular, the present disclosure relates to a biopsy device comprising a flexible surgical instrument that can be inserted through a catheter into a peripheral vascular access site for performing a soft tissue biopsy.

Background Art

[0002] Current methods for performing a liver biopsy may include the inherent risk of serious complications, which often cause patients to choose to delay the biopsy procedure, subsequently delaying diagnosis and treatment intervention for liver dysfunction. Such methods may include open surgery, percutaneous liver biopsy (PLB), and transjugular liver biopsy (TJLB).

[0003] Open surgical liver biopsy directly removes liver tissue during a laparoscopic or surgical procedure. Open surgical liver biopsy in current treatment can be utilized when a surgical procedure is already being performed.

[0004] Percutaneous liver biopsy (PLB) may involve extracting a core sample of liver tissue using a biopsy needle inserted through the abdominal wall. In PLB, a hole is made in the liver capsule, and a high penetration depth is required to reach its parenchyma. This procedure can often provide a good biopsy sample, but this procedure is invasive and painful and may be associated with a significant risk of serious complications, including a significant risk of death (1 in 250). If the initial biopsy fails and additional biopsy samples are required, additional needle punctures may be necessary, increasing the risk of complications even further. Therefore, PLB patients may be placed under observation for several hours after the procedure to ensure no intraperitoneal bleeding due to puncture of the liver capsule or blood vessels.

[0005] TJLB involves accessing the liver by inserting a rigid metal catheter into the right or left jugular vein and guiding it through the right ventricle of the heart into the hepatic veins of the liver. A large-bore needle pointed downwards from the catheter is used to remove liver tissue from the center. A large number of samples are often required for satisfactory analysis.

[0006] Similar to PLB, TJLB avoids the risk of undetected bleeding into the peritoneum because any bleeding from the needle puncture returns to the hepatic vein. However, because TJLB involves guiding a rigid metal catheter through major organs and blood vessels, this procedure can lead to serious complications such as bleeding, arrhythmias, vascular perforation, pneumothorax, or death. While TJLB is sometimes considered safer than PLB, it carries the risk of new complications associated with the jugular vein access site.

[0007] Existing single-use disposable mechanisms for obtaining percutaneous biopsy tissue samples fire a spring-loaded stylet at high speed into the target lesion, immediately followed by the firing of a coring needle or cutting cannula to obtain a sample from the target lesion. The firing mechanism is configured so that the stylet and coring needle are integrated within the mechanism. While this may be sufficient for ultrasound-assisted percutaneous applications, it poses considerable risks for TJLB. There is an inherent risk that the mechanism may fire prematurely due to operator error or malfunction of the firing mechanism during insertion through the right brachiocephalic vein or superior vena cava if the firing mechanism is accidentally overloaded before insertion. Furthermore, performing TJLB multiple times to ensure sufficient sample collection for analysis poses significant risks to the patient.

[0008] Therefore, to reduce the risk of major complications associated with PLB and TJLB procedures, there is a need for transvenous biopsy devices that can be introduced into the patient's body, for example, via the ulnar cephalic vein / radial cephalic vein, into the peripheral venous system of the arm, and that can be flexibly guided through the venous system to perform soft tissue biopsies on target organs such as the liver.

[0009] Patent Document 1, published by the applicant on May 31, 2019 (its disclosure is incorporated herein by reference), describes a balloon-fixed biopsy device. However, while this was sufficient for most applications, several problems arose. The distal end of the balloon catheter is fixed to the hepatic vein when the balloon inflates, so insufficient force is generated by the recoil to penetrate the organ.

[0010] Given the current equipment used to obtain core specimens from soft tissue, it is desirable to provide an improved biopsy apparatus. [Prior art documents] [Patent Documents]

[0011] [Patent Document 1] International Publication No. 2019 / 103694A1 [Overview of the project]

[0012] One embodiment of the present disclosure relates to a biopsy device for performing a soft tissue biopsy on any major organ via the venous system. The biopsy device of the present disclosure is a system that is sufficiently flexible so that it can be guided manually and with existing tools, namely fluoroscopy for visualization and a simple guidewire. Once positioned, the biopsy device of the present disclosure can generate sufficient force, which can be transmitted to the distal cut end of the system to penetrate the organ and obtain a biopsy. Furthermore, the biopsy device of the present disclosure allows for the withdrawal of a portion of the system along with the soft tissue sample for examination and collection without completely withdrawing the system. If the previous sample is found to be insufficient, the withdrawn portion of the system can be reinserted later with minimal risk of additional sample collection.

[0013] According to embodiments of the present disclosure, a biopsy device is provided for obtaining a biopsy sample of a target organ in a subject, the biopsy device comprising a housing and an elongated tube having a first proximal end and a first distal end, the first distal end being positioned at the biopsy site of the target organ, and the first proximal end comprising a first locking mechanism, the first locking mechanism being coupled to the housing.

[0014] According to some embodiments, the biopsy device may further comprise a biopsy needle having a second proximal end and a second distal end, configured to be positioned in an elongated tube for guidance to the biopsy site and to exit from the first distal end of the elongated tube to penetrate into the tissue of the target organ at the biopsy site and to obtain a biopsy sample of the target organ at the biopsy site, wherein the second proximal end of the biopsy needle comprises a second locking mechanism, the second locking mechanism being coupled to a housing. Optionally, the first locking mechanism comprises a swivel and a bayonet. Optionally, the first locking mechanism comprises opposing extensions configured to engage with the inside of an opening in the housing. Optionally, each of the opposing extensions comprises a shoulder configured to engage with the inside of an opening in the housing. Optionally, the first locking mechanism is freely rotatable around the elongated tube.

[0015] According to some embodiments, the biopsy needle comprises a coring needle and a stylet needle. A second locking mechanism may comprise a cartridge and a stylet lug. Optionally, the coring needle comprises one or more spiral cuts extending longitudinally around and along the coring needle. Optionally, the one or more spiral cuts have a constant pitch, or the one or more spiral cuts have a variable pitch.

[0016] According to some embodiments, the stylet needle has notches along its circumference and longitudinally along the stylet needle. Optionally, the notches are opposite each other. Optionally, the notches are less than 30% of the diameter of the stylet needle. Optionally, the notches are rotated 90 degrees axially.

[0017] According to some embodiments, the housing further comprises an advancement mechanism configured to advance a stylet needle to penetrate the tissue of a target organ at the biopsy site, and a firing mechanism configured to fire a coring needle to penetrate the tissue of a target organ at the biopsy site, thereby obtaining a biopsy sample of the target organ at the biopsy site. Optionally, the advancement mechanism is actuated by rotation. Optionally, the firing mechanism is configured to fire the coring needle only when the stylet needle has fully advanced. Optionally, the stylet needle has a recess at a third distal end.

[0018] According to some embodiments, a method for obtaining a biopsy sample of a target organ in a subject using a biopsy device, the method comprising the steps of providing a biopsy device, the biopsy device comprising a housing, an elongated tube having a first proximal end and a first distal end, the first distal end being positioned at the biopsy site of the target organ, the first proximal end having a first locking mechanism, the first locking mechanism being coupled to the housing, and a biopsy needle having a second proximal end and a second distal end, the biopsy needle being positioned within the elongated tube to guide it to the biopsy site A method is provided comprising the steps of: inserting the elongated tube percutaneously into a first blood vessel of the limb of the subject; and guiding the first distal end of the elongated tube from the first blood vessel through the vascular system of the subject into a second blood vessel of the target organ near the biopsy site. The method comprises: a biopsy needle having a first distal end of an elongated tube that exits to penetrate into the tissue of the target organ at the biopsy site and is configured to obtain a biopsy sample of the target organ at the biopsy site, the second proximal end of the biopsy needle having a second locking mechanism, the second locking mechanism being coupled to a housing; and guiding the first distal end of the elongated tube from the first blood vessel through the vascular system of the subject into a second blood vessel of the target organ near the biopsy site.

[0019] According to some embodiments, the first locking mechanism comprises opposing extensions configured to engage inside the opening of the housing. Optionally, coupling an elongate tube to the housing using the first locking mechanism can include compressing the opposing extensions and inserting the compressed opposing extensions into the opening of the housing. Optionally, the biopsy needle comprises a core needle and a stylet needle.

[0020] According to some embodiments, the method can further include pushing the stylet needle into the target organ at the biopsy site until the stylet needle is fully advanced and pushing the core needle into the target organ at the biopsy site.

Brief Description of the Drawings

[0021] To better understand the present disclosure and its practical applications, the following drawings are provided and referred to hereinafter in this specification. Note that the drawings are shown by way of example only and are not intended to limit the scope of the present invention in any way.

[0022] [Figure 1A] A biopsy device according to some embodiments of the present disclosure is schematically shown. [Figure 1B] An exploded view of a biopsy device according to some embodiments of the present disclosure is schematically shown. [Figure 2] Figures 2A, B schematically show a needle assembly according to some embodiments of the present disclosure. [Figure 3A] A needle assembly according to some embodiments of the present disclosure is schematically shown. [Figure 3B] A core needle of a needle assembly according to some embodiments of the present disclosure is schematically shown. [Figure 3C] A stylet needle of a needle assembly according to some embodiments of the present disclosure is schematically shown. [Figure 3D] The bending of a stylet needle without a notch according to some embodiments of the present disclosure is schematically shown. [Figure 3E] Schematically shows the bending of a notched stylet needle according to some embodiments of the present disclosure. [Figure 4] Schematically shows a mechanism by which a needle assembly is locked to a gun according to some embodiments of the present disclosure. [Figure 5] Figures 5A - D schematically show cross - sections of a biopsy device showing the process of locking a needle assembly and loading it into a gun according to some embodiments of the present disclosure. [Figure 6] Schematically shows a cross - section of a biopsy device with a needle assembly and catheter connected to a gun before firing according to some embodiments of the present disclosure. [Figure 7] Schematically shows a cross - section of a biopsy device with a needle assembly and catheter connected to a gun after firing according to some embodiments of the present disclosure. [Figure 8] Schematically shows a cross - section of a biopsy device with a needle assembly and catheter connected to a gun with the firing pin retracted according to some embodiments of the present disclosure.

[0023] Here, particularly referring to the drawings in detail, it is emphasized that the details shown are by way of example and for the purpose of an exemplary description of embodiments of the present disclosure. In this regard, from the description accompanied by the drawings, it will be apparent to those skilled in the art how embodiments of the present disclosure can be implemented.

[0024] Generally, the same or overlapping or equivalent or similar structures, elements, or parts appearing in one or more drawings are assigned the same reference numerals, and optionally additional characters are assigned to distinguish similar entities or modifications of entities, repeated numbering, and / or description may not be done. References to previously presented elements are shown without necessarily further citing the drawings or descriptions in which they appear.

[0025] The dimensions of the components and features shown in the drawings are selected for convenience or clarity and are not necessarily shown to scale or in actual perspective. For convenience or clarity, some elements or structures are not shown, or are shown only partially, and / or are shown in different perspectives or from different viewpoints. [Modes for carrying out the invention]

[0026] In the following detailed description, many specific details are provided to provide a complete understanding of the invention. However, those skilled in the art will understand that the invention can be carried out without these specific details. In other examples, well-known methods, procedures, components, modules, units and / or circuits are not described in detail so as not to obscure the invention.

[0027] Embodiments of the present invention are not limited in this respect, but the terms “plurality” and “a plurality” as used herein may include, for example, “multiple” or “two or more.” The terms “plurality” or “a plurality” may be used throughout this specification to describe two or more components, devices, elements, units, parameters, etc. Unless expressly otherwise, embodiments of the methods described herein are not restricted to any particular order or arrangement. In addition, embodiments of the methods described or elements of embodiments of the methods may occur or be performed at the same time, simultaneously or in parallel. Unless specifically otherwise stated, the use of the conjunction “or” as used herein should be understood as comprehensive (any or all of the options described).

[0028] Embodiments of this disclosure describe a core needle biopsy device for peripheral access (e.g., transcephalic venous access) that overcomes the problem of insufficient force transmission from the handle to the cutting cannula and stylet at the biopsy site. The core needle biopsy device further includes a safety mechanism that prevents premature ejection of the coring needle, as well as providing separate locking mechanisms for the cannula and biopsy needle. Finally, this disclosure includes stabilizing the balloon-fixed catheter and enabling the advancement of the stylet needle and coring needle of the biopsy needle by coupling the balloon-fixed catheter with a mechanism that advances the stylet needle and coring needle.

[0029] In accordance with some embodiments of this disclosure, Figure 1A schematically shows a biopsy device 100, while Figure 1B schematically shows an exploded view of the biopsy device 100. The biopsy device 100 comprises a gun 300, a needle assembly 400, and an elongated tube 376. The biopsy device 100 is used to launch a biopsy needle 363 inserted into a patient via the elongated tube 376. For illustrative purposes, the elongated tube 376 may be described as a catheter 376 in this description, but it should be understood that other elongated tubes, such as a cannula, may be used. The catheter 376 comprises a proximal end 373 and a distal end 375. The distal end 375 of the catheter 376 is positioned at the biopsy site of the target organ. The target organ may be any organ, including liver parenchyma.

[0030] According to some embodiments of the present disclosure, the stylet needle 302 and the coring needle 304 are combined with a cartridge 308 and a stylet lug 310 as a needle assembly 400 (see Figures 2A and 2B). The catheter 376 is coupled to the gun 300 using a first locking mechanism comprising a swivel 374 and a bayonet 378. The swivel 374 is fixed to the proximal end of the catheter 376. The bayonet 378 comprises opposing extensions or forks 382, ​​each having a shoulder 384 at the tip of the fork 382. Preferably, there are two opposing extensions or forks 382. The bayonet 378 is freely rotatable around the swivel 374 fixed to the catheter 376.

[0031] According to some embodiments of the present disclosure, the gun 300 comprises a housing 312 formed by a left housing portion 312a and a right housing portion 312b. The housing 312 holds several components constituting a forward and firing mechanism, including a ratchet bolt 306, a pawl 316, a handle lever 318, a compression spring 320, a firing pin 322, a firing screw 324, a pawl release nut 326, and a rotary release knob 328. The forward and firing mechanisms are described in more detail below with reference to Figure 6. One or more self-tapping screws 330 hold the housing 312 together, and a larger self-tapping screw 332 passes through the left housing portion 312a, the handle lever 318, and the right housing portion 312b. Preferably, there are three self-tapping screws 330 holding the housing 312 together. Optionally, the self-tapping screws 330 are 3 mm screws, while the larger self-tapping screws 332 are 3.5 mm screws. Those skilled in the art will understand that the self-tapping screws 330 and 332 may be of any size, as long as they fasten the housing 312 and the handle lever 318 together.

[0032] According to some embodiments of this disclosure, the ratchet bolt 306 slides freely within a channel formed in the housing 312 by closing the left portion 312a and the right portion 312b of the housing. Similarly, the pawl 316 also slides within a channel formed in the housing 312 by closing the left portion 312a and the right portion 312b of the housing and has a pawl locking tooth 346 that engages with the underside of the ratchet bolt 306. The handle lever 318 rotates around a shaft divided between the left portion 312a and the right portion 312b of the housing. The ratchet bolt 306 and the pawl 316 pass through the handle lever 318 and interact directly with the handle lever 318. The compression spring 320 is located within the rear of the ratchet bolt 306 and the housing 312. The firing pin 322 is axially aligned with the compression spring 320, the needle assembly 400 and the ratchet bolt 306. The firing screw 324 engages internally with a claw release nut 326 and externally with a firing pin 322. The release knob 328 is fitted into the rear of the housing 312, axially aligned, and secured to the firing screw 324.

[0033] According to some embodiments of the present disclosure, the housing 312 comprises a circular opening or socket 380, which receives the forks 382 of the bayonet 378. The forks 382 of the bayonet 378 are compressed together during insertion and then spring apart once inserted into the circular opening or socket 380. The shoulders 384 of each fork 382 hook into the inside of the housing 312, thus securing the bayonet 378 to the housing 312. The housing 312 further comprises facets 386 on the left side 312a and the right side 312b of the housing, which allow for a tighter alignment of the gun 300 to the trajectory of the catheter 376.

[0034] Figures 2A and 2B schematically show a needle assembly 400 according to an embodiment of the present disclosure. The needle assembly 400 comprises a biopsy needle 363 consisting of a stylet needle 302 and a coring needle 304, a cartridge 308, and a stylet lug 310. The biopsy needle 363 has a proximal end 365 and a distal end 303. The cartridge 308 and the stylet lug 310 constitute a second locking mechanism that locks the proximal end 365 of the biopsy needle 363 to the gun 300. In particular, the cartridge 308 locks the proximal end of the coring needle 304 to the gun 300, while the stylet lug 310 locks the proximal end of the stylet needle 302 to the cartridge 308 and the gun 300. The coring needle 304 passes through a channel in the cartridge 308, is aligned by their common axis, and is firmly bonded to the cartridge 308. The stylet needle 302 passes through the coring needle 304 and is firmly bonded to the stylet lug 310 located at the proximal end of the cartridge 308. The stylet lug 310 has channels 354 parallel to the direction of linear displacement. Preferably, there are two channels 354, which are 180 degrees apart and equally spaced. Each of the channels 354 has a raised cylindrical bump 358. The cartridge 308 has a plurality of longitudinal latch hooks 356 located within the proximal end of the cartridge 308, each of which is aligned with each of the channels 354 on the stylet lug 310 to prevent the raised cylindrical bumps 358 from sliding freely. The latch hooks 356 also serve to lock the stylet lug 310 and the stylet needle 302, preventing displacement relative to the cartridge 308 when the needle assembly 400 is inserted through the catheter 376.

[0035] Figures 3A, 3B, and 3C schematically show a needle assembly 400, a coring needle 304 of the needle assembly 400, and a stylet needle 302 of the needle assembly 400, respectively, according to several embodiments of the present disclosure. The coring needle 304 is a thin-walled stainless steel tube that slides freely on the stylet needle 302. The stylet needle 302 may be a 16g needle with a sample collection recess 360 at its distal end having a smaller cross-sectional area than the rest of the stylet needle 302. Both the coring needle 304 and the stylet needle 302 are too rigid to pass, for example, a bend in the patient's right brachiocephalic vein without puncturing the catheter 376 or damaging the distal tip of one or both needles. To pass a tight bend in the right brachiocephalic vein, the stylet needle 302 and the coring needle 304 must exhibit flexibility determined by four variables. To protect the sample collection recess 360 of the stylet needle 302, the distal end of the needle assembly 400 is given maximum flexibility.

[0036] According to some embodiments of the present disclosure, the coring needle 304 is adapted to be more flexible by introducing a spiral cut of length "a" along its axial length with a pitch length "b" between each spiral. Preferably, the width of the spiral cut may be 0.01 to 0.3 mm, ideally 0.1 mm. Length "a" may be any length extending along the coring needle 304. The spiral cut may be continuous along length "a" or segmented. Those skilled in the art will understand that length "a" does not need to extend all the way to the cartridge 308. Preferably, the starting point of the spiral cut at the distal end of the coring needle 304 is located 2.5 mm away from the inclined distal end of the coring needle 304. The pitch length "b" between each spiral may be any length, preferably 6 mm. The pitch length "b" may be constant or vary along the entire length "a" of the spiral cut. Preferably, the pitch length "b" is 2 mm at the distal end of the coring needle 304, increasing to 4 mm in the middle portion of the coring needle 304, and increasing to 6 mm at the proximal end of the coring needle 304. Those skilled in the art will understand that the pitch "b" of the coring needle 304 must be small enough so that each individual spiral segment does not take a linear orientation and each spiral conforms to the radius of the brachiocephalic vein when the coring needle 304 is guided through the catheter 376 near the brachiocephalic vein. If the spiral segments take a linear orientation, the ends of each spiral will be misaligned, and the relatively right-angle corners of each end may potentially wear the inside of the catheter 376. Also, those skilled in the art will understand that if the pitch "b" is too small, the sum of all the gaps between each spiral will be compressed during firing, effectively reducing the penetration depth of the coring needle 304.

[0037] According to some embodiments of the present disclosure, the stylet needle 302 is adapted to be more flexible by introducing a notch of length "c" from its distal end at a pitch "d" between the notches. The length "c" may be any length extending along the stylet needle 302. Those skilled in the art will understand that the length "c" does not need to extend too close to the sample collection recess 360 of the stylet needle 302. The pitch "d" may be any length. Preferably, the pitch "d" of the notches may be 0.5 to 5 mm, ideally 2 mm.

[0038] According to some embodiments of this disclosure, Figure 3D schematically illustrates the bending of a stylet needle 302 without a notch, while Figure 3E schematically illustrates the bending of a stylet needle 302 with a notch. Because the sample collection recess 360 has a smaller cross-sectional area than the rest of the stylet needle 302, the proximal end 362 of the sample collection recess 360 represents the fixed end of the cantilever compared to the free end that penetrates the target organ, thereby causing the maximum bending moment and stress concentration to occur at the proximal end 362 of the sample collection recess 360 due to the abrupt change in cross-sectional area in response to any force applied to the distal end of the stylet needle 302 (see Figure 3D). Therefore, a notch is introduced into the stylet needle 302 to reduce the tendency for the maximum bending moment in the stylet needle 302 to occur at the proximal end 362 of the sample collection recess 360 (see Figure 3E). Preferably, the notches are opposite pairs of notches rotated 90 degrees axially and spaced by a pitch "d" with respect to a distance "c". Preferably, the notches are about 0.1 mm wide and have a depth of 30% or less of the diameter of the stylet needle 302. The notches allow the stylet needle 302 to adopt a progressive rate of change in curvature within the more flexible spiral-cut coring needle 304, and as both advance through the catheter 376, the bending force is effectively distributed along the stylet needle 302 without being concentrated at the proximal end 302 of the sample collection recess 360, so that each notch itself becomes a stress concentration point. Therefore, those skilled in the art will understand that the length "a" and pitch "b" of the coring needle 304 are adjusted for stylet needles 302 of various gauges.

[0039] In accordance with some embodiments of the present disclosure, Figure 4 schematically illustrates a mechanism by which a needle assembly 400 is locked to a gun 300. The cartridge 308 of the needle assembly 400 comprises a plurality of cartridge pegs 334. Preferably, there are two cartridge pegs 334 that are diametrically opposed to each other. The ratchet bolt 306 of the gun 300 comprises an alignment slot 336. The cartridge pegs 334 are aligned with the alignment slot 336 in the ratchet bolt 306. The needle assembly 400 is locked to the gun 300 by linear displacement followed by rotational displacement, as indicated by the arrows. Preferably, the rotational displacement is 60 to 70 degrees, and ideally 65 degrees. The ratchet bolt 306 of the gun 300 further comprises a raised projection 338 on the circular portion of the alignment slot 336, which effectively narrows the width of the alignment slot 336 and provides tactile feedback to confirm that the needle assembly 400 is secured to the gun 300. Preferably, there are two raised projections 338. When the needle assembly 400 is inserted into the gun 300 and twisted, the needle assembly 400 locks into place and the cartridge 308 is displaced simultaneously with the ratchet bolt 306. At this point, the stylet lug 310 is not yet engaged with the firing pin 322.

[0040] In accordance with some embodiments of the present disclosure, Figures 5A–5D schematically show cross-sections of a biopsy apparatus 100 illustrating the process of locking and loading a needle assembly 400 into a gun 300. Figure 5A shows the gun 300 with the needle assembly 400 inserted, ready to initiate lever operation by the handle lever 318. Figure 5B shows the gun 300 with the needle assembly 400 inserted, with the handle lever 318 fully rotated. Figure 5C shows the gun 300 with the needle assembly 400 inserted, with the ratchet bolt 306 preloading the compression spring 320 and the stylet lug 310 held by the longitudinal latch hook 356 of the cartridge 308. Figure 5D shows the gun 300 with the needle assembly 400 inserted, with the stylet lug 310 released from the longitudinal latch hook 356 of the cartridge 308.

[0041] According to some embodiments of the present disclosure, the ratchet bolt 306 comprises a gear rack 342 having multiple teeth. The gear rack 342 having multiple teeth is part of the ratchet bolt 306 and determines the range of linear displacement of the ratchet bolt 306. The handle lever 318 comprises flexible fingers 340. The flexible fingers 340 of the handle lever 318 engage with the gear rack 342. The handle lever 318 can be rotated counterclockwise when gripped. Preferably, the handle lever 318 rotates over an arc of up to 15 degrees. Each gripping or rotating motion of the handle lever 318 produces a linear displacement of the ratchet bolt 306, thereby preloading the compression spring 320 of the gun 300. Preferably, the linear displacement of the ratchet bolt 306 is equal to at least one pitch of the gear rack 342 and at most two pitches of the gear rack 342. The sum of the linear displacements, or the preload applied to the compression spring 320, is equal to the firing stroke of the coring needle 304. Optionally, the stroke is 30 mm. Those skilled in the art will understand that the stroke length can be increased or decreased by the number of teeth on the gear rack 342 and the corresponding length of the ratchet bolt 306. Each rotational movement of the handle lever 318 and the subsequent linear displacement of the ratchet bolt 306 causes a relief angle 344 on each tooth of the ratchet bolt 306, which deflects the pawl locking tooth 346 on the pawl 316 sufficiently, so that the pawl locking tooth 346 prevents engagement with the ratchet bolt 306. When the handle lever 318 is released, the cantilever spring 348, which is integrated with the handle lever 318, returns the handle lever 318 to its original position, ready for repeating the lever operation. At the same time, the pawl locking teeth 346 on the pawl 316 immediately re-engage with the ratchet bolt 306, maintaining the preload on the compression spring 320.Figures 5A and 5B show the ratchet bolt 306 as a simply supported beam, meaning that the ratchet bolt 306 is constrained at both ends by channels within the housings 312a and 312b and slides within them. However, those skilled in the art will understand that if the linear displacement of the ratchet bolt 306 continues, the ratchet bolt 306 will detach from the distal end 350 of the housing (see Figure 5C) and, when engaged by the rotational inertia of the flexible finger 340 on the handle lever 318, will appear as a cantilever itself. Therefore, to limit this rotational degree of freedom, the pivot point 352 on the cantilever spring 348 provides a tangential radial sweep that maintains a sufficient contact point with the ratchet bolt 306 and resists the moment of rotational inertia.

[0042] According to some embodiments of the present disclosure, the stylet lug 310 further comprises a small stylet lug peg 364, and the firing pin 322 further comprises a keyhole slot 366. Preferably, there are two small stylet pegs 364. As the ratchet bolt 306 approaches its full preload displacement, the small stylet lug pegs 364 on the stylet lug 310 align with the keyhole slot 366 of the firing pin 322. When the total displacement of the ratchet bolt 306 and cartridge 308 is within 2 mm of the maximum preload, the stylet lug 310 fully engages with the firing pin 322 (see Figure 5C).

[0043] According to some embodiments of this disclosure, the firing pin 322 comprises a double starting angle screw 368 and two opposing flat sections 370 along its length. The firing pin 322 cannot provide linear displacement until the firing screw 324 rotates, as the two opposing flat sections 370 along its length prevent rotation within the square alignment slot 372 of the housing 212. During the final movement of the handle lever 318 (see Figure 5B) and the linear displacement of the ratchet bolt 306, the firing pin 322 strikes the stylet lug 310 and moves away from the latch hook 356 of the ratchet bolt 306. Comparing the enlarged views of Figure 5D and Figure 5C, it is shown that the latch hook 356 is now proximal to the raised cylindrical bump 358. Once the needle assembly 400 is locked into the gun 300 and loaded, the operator can now connect the catheter 376 to the gun 300.

[0044] In accordance with some embodiments of the present disclosure, Figure 6 schematically shows a biopsy apparatus 100 in which the needle assembly 400 and catheter 376 are connected to the gun 300 before firing with the compression spring 320 fully preloaded and the claw 316 fully deformed. After the catheter 376 is connected to the housing 312, the operator advances the stylet needle 302 into the target organ by rotating the advancement mechanism, as detailed below. The advancement mechanism may be a release knob 328, which is a rotatable advancement mechanism. Other advancement mechanisms may also be available. As the catheter 376 moves when the stylet needle 302 is advanced, the bayonet 378 counteracts the equivalent counteracting force generated by the advancement and penetration of the stylet needle 302 into the patient's tissue. This is because the catheter 376 is connected to the gun 300 by the bayonet 378 independently of the stylet needle 302 and the coring needle 304. The direct connection of the catheter 376 to the gun 300 by the bayonet 378 also offers several advantages, including stabilization of the proximal end of the catheter 376 and allowing the operator to advance the stylet needle 302 without holding it on the catheter 376.

[0045] According to some embodiments of the present disclosure, the release knob 328 rotates within a perimeter channel 388 in the assembled housing 312 (see Figure 1B). During assembly, the release knob 328 aligns with a number of flat sections 390 on the shaft of the firing screw 324 (see Figures 1B and 5D). Preferably, there are three flat sections 390. As the release knob 328 is pressed into the housing 312, one or more snap-in pawls 392 having undercuts interfere with the outer circumference of the perimeter channel 388. Preferably, there are four snap-in pawls 392. When a moderate force is applied, the snap-in pawls 392 are deflected, aligning the release knob 328 and allowing it to slide further along the firing screw 324. The undercuts of each snap-in pawl 392 remain in their aligned static positions within the perimeter channel 388 or return to their original positions. The firing screw 324 can now rotate only together with the release knob 328. The launch screw 324 has a left-hand thread 394. The inner diameter provides clearance for the launch screw 324 but has a key 396 that protrudes from the inner diameter and engages with the double-start angle thread 368 of the launch screw 324. Preferably, there are two keys 396. Clockwise rotation of the release knob 328 advances the launch screw 324, the launch pin 322, the stylet lug 310, and the stylet needle 302 into the target organ. Preferably, a full one-turn clockwise rotation of the release knob 328 advances the launch screw 324 6 mm into the target organ, while the claw release nut 326 is displaced 1.75 mm, the amount of which is equal to the pitch of the left-hand thread 394 of the launch screw 324.

[0046] According to some embodiments of the present disclosure, when the release knob 328 is turned clockwise, for example, a full five turns, two linear displacements proceed simultaneously, advancing the launch pin 322, the stylet lug 310, and the stylet needle 302. During the final turn, the pawl release nut 326 continues to apply compressive force to the angled heel 398 of the pawl 316. The angled heel 398 is essentially a small cantilever, its length and thickness adjusted according to the polymer from which it is molded so that it deforms and displaces linearly. This linear displacement presses the neck of the pawl 402 against a raised circular stop 404 on the handle lever 318, with either side of the handle lever 318 straddling the ratchet bolt 306. These raised circular stops 404 serve two purposes. First, they return the handle lever 318 completely, ensuring that the flexible finger 340 is released from the ratchet bolt 306. Secondly, the neck of the claw 402 is further compressed against the raised circular stop 404, and the horn of the claw 406 makes firm contact with the gap channel 408 of the handle lever 318. The neck of the claw 402 is now a simply supported beam, and the maximum deflection occurs at the center of the beam. That is, the claw locking teeth 346 plastically deform away from the gear rack 342 on the ratchet bolt 306. The stylet needle 302 is now fully advanced by the advance mechanism of the gun 300.

[0047] According to some embodiments of the present disclosure, the operator operates the firing mechanism by pressing the handle lever 318 after the last rotation of the release knob 328, thereby firing the ratchet bolt 306. Pressing the handle lever 318 causes the pawl lock teeth 346 to disengage from the gear rack 342 and releases all preload on the compression spring 320, thus firing the ratchet bolt 306. Once the ratchet bolt 306 is fired, the cartridge 308 and coring needle 304 coupled to the ratchet bolt 306 are fired towards the patient's target organ, so that the sample is collected in the sample collection recess 360.

[0048] According to some embodiments of the present disclosure, Figure 7 schematically shows a cross-section of a biopsy apparatus 100 with a needle assembly 400 and catheter 376 connected to a gun 300 after firing. During firing of the ratchet bolt 306, the stylet needle 302 is restrained by a small stylet lug peg 364 on a stylet lug 310, which is grasped by a keyhole slot 366 on a firing pin 322. The coring needle 304 enters the target organ, scrapes, and captures a tissue sample in the space between the sample collection recess 360 and the inside of the coring needle 304.

[0049] According to some embodiments of the present disclosure, Figure 8 schematically shows a cross-section of a biopsy apparatus 100, which includes a needle assembly 400 and a catheter 376 connected to a gun 300 with the firing pin 322 retracted. After firing, the release knob 328 must be rotated counterclockwise until it can no longer be rotated. This can be confirmed by the appearance of the proximal end of the firing pin 322 protruding from the firing screw 324, as shown in Figure 8. The firing pin 322 has released the stylet lug 310. The needle assembly 400 can now be rotated and withdrawn from the gun 300, and the gun 300 is now ready to receive another set of needle assemblies 400.

[0050] A method for performing a biopsy using a biopsy apparatus 100 comprising a gun 300, a needle assembly 400, and a catheter 376 is described below according to some embodiments of the present disclosure. An operator, such as a physician, can insert the catheter 376, to which a swivel 374 and a bayonet 378 are attached, into a first blood vessel of the patient. The operator guides the distal end 375 of the catheter 376 through the vascular system to a second blood vessel near the biopsy site of the target organ. Once the catheter 376 is secured in the second blood vessel of the target organ, the needle assembly 400 is inserted through the catheter 376 to a depth where the distal end of the stylet needle 302 approaches the target organ but has not yet penetrated it. The operator can then introduce the gun 300 into the proximal end 365 of the biopsy needle. The operator can connect the gun 300 to the needle assembly 400 by fully inserting the needle assembly 400 into the handle 300 and locking the needle assembly 400 to the gun 300 by rotating the needle assembly 400 counterclockwise (see Figure 4).

[0051] The operator can squeeze and release the handle lever 318 of the gun 300 several times until the stylet lug 310 is released from the longitudinal latch hook 356 of the cartridge 308 and the handle lever 318 can no longer be squeezed (see Figures 5A-5D). This indicates that the firing mechanism of the gun 300 is fully loaded and ready to fire. At this point, the gun 300 should be aligned with the trajectory of the needle assembly 400. The facets 386 on both sides of the gun housing 212 allow for closer alignment with the patient's arm. At this point, the operator can attach the catheter 376 to the gun 300 (see Figure 6). The operator can snap-lock the bayonet 378, which is swung around the proximal end of the catheter 376 and inserted into the gun 300. This stabilizes the proximal end of the catheter 376 and ensures that the gun 300 maintains a fixed relationship with the catheter 376 when the stylet needle 302 advances and the coring needle 304 is fired, by directly connecting the catheter 376 to the gun 300.

[0052] The interaction between the needle assembly 400 and the catheter 376 ensures that the stylet needle 302 is positioned relative to the target organ or slightly penetrating it. The operator can then advance the needle stylet 302 into the target organ by rotating the release knob 328 at the rear of the gun 300 clockwise, with a full rotation advancing the stylet needle 302 6 mm. After five full rotations, during the sixth rotation, the stylet needle 302 is fully advanced and the ratchet bolt 306 is ready to fire. After the stylet needle 302 is fully advanced, the operator squeezes the handle lever 318, releasing the coring needle 304 via the ratchet bolt 306 and firing it into the target organ (see Figure 7). At any time before this release, the needle stylet 302 can be retracted and repositioned. After firing, the operator can retract the release knob 328 by rotating it counterclockwise until it can no longer be rotated (see Figure 8). This releases the internal firing mechanism from the needle assembly 400. The needle assembly 400 can then be removed by rotating it clockwise. The gun 300 is ready to accept another set of needles if additional biopsy samples are needed.

[0053] This specification discloses various embodiments. Features of a particular embodiment may be combined with features of other embodiments. Thus, a particular embodiment may be a combination of features of multiple embodiments. The foregoing description of embodiments of the present invention is presented for illustrative and explanatory purposes. It is not intended to be exhaustive or to limit the invention to the exact forms disclosed. Those skilled in the art should understand that many modifications, variations, substitutions, alterations, and equivalents are possible in light of the above teachings. Accordingly, it should be understood that the appended claims are intended to include all such modifications and alterations that fall within the true spirit of the invention.

[0054] While certain features of the present invention are illustrated and described herein, many modifications, substitutions, alterations, and equivalents will be conceivable to those skilled in the art. Therefore, it should be understood that the appended claims are intended to include all such modifications and alterations that fall within the true spirit of the present invention.

Claims

1. A biopsy device for obtaining a biopsy sample of a target organ in a subject, wherein the biopsy device is Housing and An elongated tube having a first proximal end and a first distal end, The first distal end is positioned at the biopsy site of the target organ, and the first proximal end is equipped with a first locking mechanism, the first locking mechanism being a long, slender tube coupled to the housing, A biopsy needle having a second proximal end and a second distal end, The biopsy needle is positioned within the elongated tube for guidance to the biopsy site, and exits from the first distal end of the elongated tube to penetrate into the tissue of the target organ at the biopsy site, thereby obtaining a biopsy sample of the target organ at the biopsy site. Equipped with, The biopsy needle has a second locking mechanism comprising a cartridge and a stylet lug attached to the second proximal end of the biopsy needle, wherein the cartridge and the stylet lug are coupled to and housed within the housing. Biopsy device.

2. The biopsy apparatus according to claim 1, wherein the first locking mechanism comprises a swivel and a bayonet.

3. The biopsy apparatus according to claim 2, wherein the first locking mechanism comprises opposing extensions configured to engage with the opening of the housing.

4. The biopsy apparatus according to claim 3, wherein each of the opposing extensions comprises a shoulder portion configured to engage with the opening of the housing.

5. The biopsy apparatus according to any one of claims 1 to 4, wherein the first locking mechanism is freely rotatable around the elongated tube.

6. The biopsy apparatus according to any one of claims 1 to 4, wherein the biopsy needle comprises a coring needle and a stylet needle.

7. The biopsy apparatus according to claim 6, wherein the coring needle is provided with one or more spiral cuts extending longitudinally around and along the coring needle.

8. The biopsy apparatus according to claim 7, wherein the one or more spiral cuts have a constant pitch.

9. The biopsy apparatus according to claim 7, wherein one or more spiral cuts have a variable pitch.

10. The biopsy apparatus according to claim 6, wherein the stylet needle has a notch along its circumference and longitudinally along the stylet needle.

11. The biopsy apparatus according to claim 10, wherein the notches are located on opposite sides.

12. The biopsy apparatus according to claim 10 or 11, wherein the notch is less than or equal to 30% of the diameter of the stylet needle.

13. The biopsy apparatus according to any one of claims 10 to 12, wherein the notch is rotated 90 degrees in the axial direction.

14. The aforementioned housing further, A forward-moving mechanism configured to advance the stylet needle in order to penetrate into the tissue of the target organ at the biopsy site, A launching mechanism configured to launch the coring needle to penetrate into the tissue of the target organ at the biopsy site, thereby obtaining a biopsy sample of the target organ at the biopsy site, A biopsy apparatus according to any one of claims 6 to 13, comprising:

15. The biopsy apparatus according to claim 14, wherein the forward movement mechanism is operated by rotation.

16. The biopsy apparatus according to claim 14 or 15, wherein the firing mechanism is configured to fire the coring needle only when the stylet needle has fully advanced.

17. The biopsy apparatus according to any one of claims 6 to 16, wherein the stylet needle has a recess at the third distal end of the stylet needle.

Images