Endoscopic multiple sample bioptome with enhanced biting action

Technical Field The present invention relates to an endoscopic surgical instrument. In particular, the present invention relates to an instrument for extracting a plurality of biopsy tissue samples. Conventional Techniques Endoscopic biopsy procedures are typically performed using an endoscope and an endoscopic biopsy forceps device (Bioptom). An endoscope is a long flexible tube that carries a fiber lens and has a narrow lumen into which a bioptom is inserted. The bioptom typically comprises a long flexible coil, which has a pair of opposing jaws at the tip and a manual actuating means at the anterior end. The jaw opens and closes when the operating means is operated. At the time of sampling the biopsy tissue, the surgeon guides the endoscope to the biopsy site while looking at the biopsy site through the fiber lens of the endoscope. The bioptom is inserted through the narrow lumen of the endoscope until its opposing jaw reaches the biopsy site. Looking at the biopsy site through the fiber lens of the endoscope, the surgeon positions the jaw around the tissue to be sampled and manipulates the actuation means so that the jaw closes around the tissue. A sample of tissue is then excised and / or torn from the biopsy site while being captured between the jaws of the bioptom. With the jaw closed, the surgeon pulls the bioptom out of the endoscope to open the jaw and collects a biopsy tissue sample. Biopsy tissue sampling means often require the collection of several tissue samples from the same or different biopsy sites. Unfortunately, most bioptomies are limited to the removal of a single tissue sample, and this device is used endoscopically after removal of a single tissue sample and prior to use to remove another tissue sample again. Must be pulled out from. Most biopsimes are limited to single sample retrieval because of the limited space between the jaws of the biopsy forceps. Several attempts have been made to provide an instrument that allows several tissue samples to be removed before the instrument has to be withdrawn once. The problem with providing such instruments is that they are extremely small in size due to the narrow lumen of the endoscope. It must be combed and the instrument must be flexible in order to insert it into the endoscope cavity. Therefore, some known multi-sample biopsy instruments have been excluded from endoscopic utility due to their size and hardness. These include the "punch-suction" instruments disclosed in US Pat. No. 3989033 granted to Halpern et al. And US Pat. No. 4522206 granted to Whipple et al. Both of these devices have a hollow tube having a punch at the tip and a vacuum source connected to the front end of the hollow tube. The tissue sample is cut out at the punch and aspirated from the biopsy site via a hollow tube. However, it is generally recognized that it is virtually impossible to aspirate tissue samples through a long and narrow flexible bioptom. Efforts have been made to provide multiple sampling capabilities for instruments that must pass through the narrow lumen of the endoscope. These efforts are focused on providing a tubular storage space at the tip of the instrument to allow several tissue samples to be accumulated before the instrument is withdrawn from the endoscope. For example, US Pat. No. 4,617,53, granted to Lifton, discloses that a rigid tubular member is attached to the tip of a first flexible tube. The tubular member has a lateral opening, and a concentric tubular knife blade is slidably mounted inside the tubular member. A second flexible tube concentric with the first tube is connected to the knife blade to move the knife blade inside the tubular member with respect to the lateral opening. A third flexible tube with a plunger end is mounted inside the second flexible tube and a vacuum source (syringe) is connected to the front end of the third tube. To remove the tissue sample, place the lateral opening of the tubular member at the biopsy site, apply a vacuum with a syringe to pull the tissue into the lateral opening, and push the second flexible tube forward with a knife blade. Is done by moving across the lateral opening. As a result, the tissue sample is cut out and the tubular part Inside the material, it is trapped inside the tubular knife. A third flexible tube is then pushed forward to move the plunger end relative to the tissue sample and pushes the tissue sample forward into the tubular storage space at the tip of the tubular member. Approximately 6 samples can be stored in the tubular member, after which the instrument is withdrawn from the endoscope. Six samples are collected by removing the tip plug on the tubular member and pushing on a third flexible tube whose plunger end ejects the sample. This Lifton patented device has some obvious drawbacks. First, it is often difficult to obtain tissue samples laterally to this device. Second, to facilitate the acquisition of lateral samples, syringes are used to facilitate the pulling of tissue into the lateral opening. However, this originally means that the 2-step procedure (positioning and cutting) becomes 3 steps (positioning, suction, cutting). In addition, the use of syringes requires additional manpower. Third, the Lifton patent adds a fourth step to the biopsy procedure as it requires the tissue sample to be pushed into the storage space. Thus, the Lifton patent ultimately requires surgeons and assistants to bear a substantial burden, much of which is pushing the tube, a task of thinking that goes against classical biopsy sampling. Virtually all endoscopic instruments have a preferred mode of operation in which the gripping action of the tip of the device is made more effective by the gripping action of the anterior end of the device. The jaw of a classic biopsy forceps is closed by squeezing a manual actuating member in a syringe-like manner. A more convenient endoscopic multi-sample biopsy device is disclosed in US Pat. No. 5,171,255, granted to Rydell. Rydell offers mobile endoscopic instruments with a knife-shaped cutting tube at the tip. A coaxial metal bed is connected to the tension wire and operated in the same way as conventional biopsy forceps. When this metal bed is pulled into the cylinder, the tissue located between the metal floor and the cylinder is cut and pushed into the storage space inside the cylinder. This device is introspection Several samples are taken and held in the storage space before being withdrawn from the mirror. This Rydell device is effective in providing a multi-sample instrument in which each sample is obtained in a traditional two-step procedure (positioning and cutting), but it is still often a problem in lateral cutting. Limited to the method. Conventional biopsy forceps have a jaw that allows the tissue to be gripped anteriorly or laterally. Even this makes it difficult to position the jaw around the tissue to be collected. Lateral sampling is even more difficult. The parent application, U.S. Patent Application No. 08/189937, discloses an endoscopic multi-sample bioptom with a hollow outer member and an inner member that extends through it and is displaced in the axial direction. .. The front ends of the outer and inner members are connected to an actuator so that one can be displaced in the axial direction with respect to the other. The tip of the outer member is connected to one of a tube with a sharp tip edge and the jaw assembly, and the tip of the inner member is connected to the other. The jaw assembly includes a pair of opposing, preferably toothed jaw cups, each jaw cup connected to a base member by an elastic arm. This elastic arm is bent and presses the jaws in a direction away from each other. The base member is mounted inside the cylinder, and the jaw assembly and the cylinder move in the axial direction with respect to each other to pull the elastic arm into the cylinder and cause both of these jaw cups to perform a bite action. However, due to the shape of the elastic arms, these arms tend to bend inward as the tube moves over the arms, preventing complete closure of the jaw. As a result, the optimum bite action cannot be obtained. Description of the Invention Therefore, an object of the present invention is to provide an endoscopic multi-sample bioptom that is not limited to lateral tissue sampling. Another object of the present invention is to provide an endoscope multiple sample bioptom that is easy to operate. Another object of the present invention is to provide an endoscopic multi-sample bioctome that is not expensive to manufacture. Yet another object of the present invention is of conventional biopsy forceps. It is to provide an endoscopic multi-sample bioptom that has all the advantages and in addition can collect multiple samples. Yet another object of the present invention is to provide an endoscopic bioptom with a fully closed jaw. Yet another object of the present invention is to provide an endoscopic bioptom with a high degree of bite action. According to these purposes, described in detail below, the endoscopic bioptom of the present invention includes a relatively long flexible member having a lumen, which flexible member is axially flexible extending through the lumen. It has a sex wire. The flexible member and the front end of the wire are connected to a manual actuating means to allow one of the flexible member and the wire to be displaced axially with respect to the other. The tip of the flexible member is connected to the jaw assembly. The tip of the wire is connected to a slidable tube over the jaw assembly. The jaw assembly includes a pair of jaw cups facing each other, each jaw cup is connected to a base member by a thin arm, and each jaw cup has a sharp cutting edge. The thin arm of each jaw is an elastic member, including a portion bent away from the longitudinal axis of the tube to position the jaw cups substantially apart from each other. The base member of the jaw assembly is mounted inside the tube and the arm of the jaw is pulled into the tube by axial movement of one of the jaw assembly and the tube, or the tube is of the jaw. It is moved on the arm, which fits the jaw cup into a bite-acting state. A closing cam is provided on the jaw cup to ensure that the jaw is completely closed and in a bite-acting state. The closing cam is preferably an inclined surface on the outer surface of the jaw cup, which is engaged by a cylinder to further move the jaw cup into the closed state. In addition, to facilitate complete closure of the jaw cup, the closing cam prevents the tube from moving too far toward the tip on the jaw cup. Further to facilitate this complete closure, each jaw cup is preferably provided with a cutting edge located in a plane that intersects the plane on which the flexion of the jaw arm is located. Jaw cup In addition to facilitating complete closure of the endoscope in this way, the outer surface of the closed jaw will exhibit a smooth outer surface that is well tolerated by the inside of the endoscope. Other objects and advantages of the present invention will be apparent to those skilled in the art by detailed description relating to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial cross-sectional side view of the front end of the first embodiment of the present invention, and FIG. 2 is a partial perspective view of the tip of the first embodiment of the present invention with the jaw open. An enlarged side view, FIG. 3 is a magnified perspective top view of the tip of an embodiment of the present invention, FIG. 4 is a view similar to FIG. 2 showing a state in which the jaw is closed, and FIG. 5 is a first jaw assembly. Schematic diagram showing the open state of the solid, FIG. 5a is a schematic view showing the closed state of the jaw assembly of FIG. 5, FIG. 6 is a schematic view showing the open state of the second jaw assembly, FIG. 6a. 6 is a schematic view showing the closed state of the jaw assembly of FIG. 6, FIG. 7 is a schematic view showing the open state of the second embodiment of the jaw assembly of the present invention, and FIG. 7a is the jaw assembly of FIG. It is a schematic diagram which shows the closed state of a solid. Detailed Description of Preferred Examples With reference to FIGS. 1 to 4, the first embodiment of the multi-sample bioptom 10 includes a front handle 12 and a tip agonist 14. A long flexible coil 16 extending through a control wire 18 displaceable in the axial direction connects the handle 12 and the tip actuator 14. The coil 16 is preferably covered with a PTFE, FEP or polyolefin exterior 15 over substantially its entire length and a strain relief sleeve 17 covering the coil portion extending from the handle 12. The control wire 18 is preferably reasonably flexible, but inelastic in the axial direction, ideally made of 304 steel and having an outer diameter of about 0.018 inches (about 0. 46mm). The front handle 12 includes a central axis 20 and a displaceable spool 22. A knob ring 24 is provided at the front end of the shaft 20, and a cavity 26 in the longitudinal direction is provided at the tip of the shaft 20. A longitudinal slot 28 extends from the front end of the cavity 26 to the tip of the knob ring 24. The displaceable spool 22 is provided with a cross member 30 that penetrates the slot 28 of the central axis 20. The cross member 30 is provided with a central through hole 32 and a set screw 34 that engages in the radial direction. According to the first embodiment of the present invention, a short cavity 36 and a set screw 38 that engages in the radial direction are provided in the shaft 20 at the tip of the knob ring 24, and the cavity 36 is a slot 28 in the longitudinal direction. Communicate with. In this embodiment, the front end of the coil 16 extends within the central through hole 32 of the cross member 30 and is fixed there by a set screw 34. The front end of the control wire 18 is inserted through the slot 28 into the short cavity 36, where it is held by a set screw 38. From the above description, those skilled in the art will appreciate that the control wire 18 moves relative to the coil 16 due to the correlative movement between the shaft 20 and the spool 22. Such an operation activates the tip actuator 14 as described in detail below. Referring to FIGS. 2-4, the tip actuator 14 includes a tubular sleeve 40 (preferably having a sharp tip knife edge 42) and a jaw assembly 44. The jaw assembly 44 includes a pair of jaw cups 46a, 46b facing each other, each jaw cup preferably having a plurality of sharp teeth 48a, 48b arranged in the radial direction. Elastic, preferably thin arms 50a, 50b extend anteriorly from each jaw cup 46a, 46b. The tubular base member 52 connects the front ends of the arms 50a and 50b. As best shown in FIG. 2, the thin elastic arms 50a, 50b are bent away from each other at points 51a, 51b between the tubular base member 52 and the jaw cups 46a, 46b to provide the jaw cups 46a, 46b. Positioned in a direction away from each other, thereby each arm Position the tip of the base member in a plane that intersects the axis of the base member. The tubular base member 52 is attached to the tip of the flexible coil 16 by welding, soldering, crimping or any other suitable method. The sleeve 40 is connected to the tip of the control wire 18 by providing the tubular sleeve 40 with a lateral hole that engages with the bent end 18a of the control wire 18. As shown in FIGS. 2 to 4, the bent end 18a of the control wire 18 is welded into the hole 45 on the side surface of the sleeve 40. However, as described in detail in the parent application, the connection of the control wire to the sleeve is also possible by other methods. The tubular sleeve 40 is slidably mounted on the tubular base member 52 as shown in FIGS. 2 and 3, and can move in the axial direction on the elastic arms 50a and 50b as shown in FIG. It has become. According to the present invention, the jaw cups 46a and 46b are preferably provided with closing cams 47a and 47b on their outer surfaces, respectively. Each closing cam is preferably an inclined abutting portion that rises from the surface of the jaw cup toward the tip. Further, the teeth 48a, 48b (ie, apex or valley) of each jaw cup are preferably further described below as shown in FIG. 4 when the jaw is closed and with reference to FIGS. 5-7. As described in detail, the teeth are arranged in a plane angled with respect to the plane of the flexed portion of the arm so that the teeth are fully engaged with each other. As can be seen in FIG. 3, the cross sections of the jaw cups 46a and 46b are eccentric, and the widest position of the cross section is indicated by line segment 49. On the tip side of line segment 49, the jaw cup is substantially hemispherical, and on the front side of line segment 49, the jaw cup is semi-elliptical. The closing cam or the raised portions 47a and 47b are preferably located on the front side of the widest portion of the jaw portion, that is, on the front side of the line segment 49. Further, the side walls of the jaw cups 46a and 46b are inclined in the direction of the arms 50a and 50b to provide a smooth connection from the jaw cup to the arm. From the above description, and with reference to FIGS. 1 to 4, when the spool 22 and the shaft 20 are displaced from each other in the axial direction, the tubular sleeve 40 and the jaw assembly 44 are similarly axial to each other. Those skilled in the art will understand that the displacement in the linear direction, that is, the displacement from the position shown in FIG. 2 to the position shown in FIG. 4 and vice versa. In addition, the spool 22 and the shaft 20 are positioned as shown in FIG.It will be appreciated that when in place, the tubular sleeve 40 and the jaw assembly 44 are approximately located at the positions shown in FIG. 2, i.e., with the jaw open. Therefore, when the spool 22 is moved in the direction of the knob ring 24 or in the opposite direction, the tubular sleeve 40 and the jaw assembly 44 are moved to the positions shown in FIG. 4, that is, the jaw is closed. It will be further understood by those skilled in the art. Further, it will be appreciated that moving the knob ring 24 relative to the spool 22 is preferable to vice versa. This is because, in this case, unlike the opposite case, the tubular sleeve 40 is moved with respect to the jaw assembly 44. This is desirable to keep the jaw assembly moving from the tissue sample while the jaw is closed. In either case, when both the arms 50a and 50b are pulled out by the tubular sleeve 40, the arm can be connected to the tubular base member 52 rather than at each bend, as seen in FIG. Tends to flexibly move. This shape of the arm is compensated by a special arrangement of the teeth of the jaw, as can be understood from the description below. Next, referring to FIGS. 5 and 5a, the jaw assembly 101 includes a first jaw cup 102a and a second jaw cup 102b. Each jaw cup is connected to the tubular base member 104 by corresponding elastic arms 103a, 103b, respectively. The arms 103a and 103b are bent in a direction away from each other (a direction away from the longitudinal axis of the base member) at points 104a and 104b where these arms reach the base member 104. The jaw cups 102a and 102b are provided with cutting edges 105a and 105b, respectively, which may include a row of teeth or may be merely sharp edges. When the sleeve (not shown) is moved over the jaw assembly, the arms 103a, 103b flexibly move at points 104a, 104b and the jaws 102a, 102b are aligned as shown in FIG. 5a. ,in addition The more cutting edges engage with each other. It will be appreciated by those skilled in the art that in this arrangement, the arms 103a, 103b move to a position where they are substantially parallel when the jaw is closed. Therefore, the cutting edges of each jaw should be arranged so that the cutting edges are located in a plane substantially parallel to the jaw arm. Referring again to FIGS. 2-4, in that the shape of the tip-acting body 14 and the tip-acting body 14 aligning with the base member 52 due to the connection of the coil 16 and the tension wire 18. It is difficult to provide the necessary flexions 51a and 51b for the jaw arms 50a and 50b. This is because a certain amount of space is required between the base member and the bent portion of the arm to accommodate the connecting portion (18a, 45) between the tension wire 18 and the tubular sleeve 40. Next, referring to FIGS. 6 and 6a, the same jaw assembly 101 is provided with bent portions 104a'and 104b' on its arms 103a and 103b at a point on the tip side with respect to the tubular base member 104. Be done. Regardless of the position of these bends, when the sleeve (not shown) is moved on the jaw assembly, the elasticity of these arms causes the arm to bend at the connection with the base member 104. As shown in FIG. 6a, when the arms 103a and 103b are bent, the jaw cups 102a and 102b are closed, but the cutting edges 105a and 105b are not completely engaged. The reason is that the cutting edges 105a, 105b are arranged so that they are located in a plane substantially parallel to the tips of the arms 103a, 103b, while the arms 103a, due to the bends 104a', 104b', This is because 103b is not aligned parallel to each other. There are two disadvantages if the cutting edges are not fully engaged. That is, incomplete cutting action and exposed sharp edges can damage the interior of the endoscope. Therefore, the shape of the cutting edge must be changed to make the cutting edge of the jaw fully engageable. 7 and 7a show the jaw assembly 144 according to the present invention. Jaw Assembly 144 includes a first jaw cup 146a and a second jaw cup 146b. Each jaw cup is connected to the tubular base member 152 by corresponding elastic arms 150a, 150b, respectively. These arms are bent in a direction away from each other (a direction away from the longitudinal axis of the base member) at points 151a and 151b on the tip side with respect to the base member 152. The jaw cups 146a and 146b are provided with cutting edges 148a and 148b, which are arranged so as to be located in a plane that is not parallel (bent) to the tips of the respective arms 150a and 150b. ing. In particular, each cutting edge is arranged so as to be located in a plane that intersects the plane on which the tip of the jaw arm is located. When the sleeve (not shown) is moved over the jaw assembly, the arms 150a, 150b flex at the connection with the base member 152, and the jaws 146a, 146b align with each other as shown in FIG. 7a. The cutting edges 148a, 148b are substantially completely engaged with each other. Referring again to FIGS. 2 and 4, the jaw assembly 44 is provided with cutting teeth 48a, 48b, which are arranged in the plane just described so that the jaw is closed. It will sometimes be understood that the teeth are virtually completely meshed. In addition, the closing cams 47a, 47b will be found to reinforce the complete meshing of the jaw teeth, especially at the tip of the jaw. In addition, these closing cams act to prevent the sleeve 40 from moving too far toward the tip on the jaw cup. This is an important safety advantage when the sleeve 40 should be detached from the tension wire 18. This is because the closing cam prevents the sleeve from falling out of the bioptom and becoming missing in the patient's body. It will be appreciated by those skilled in the art that the bioptoms of the present invention will be used in substantially the same manner as described herein in the parent application described above. The parent application is referred to as an integral part of the present specification. However, the biop of the present invention Tomes have an advanced bite effect. Similar to the parent application Bioptom, the jaw assembly can be connected to a tension wire and a tubular sleeve connected to a coil, but not vice versa. This linking action can be performed in several different ways. Several different types of actuating means (eg, forceps grips) can be used in a manner different from the spool and knob ring arrangements shown herein. The jaw can be manufactured by several methods including stamping, laser cutting and the like. In a currently preferred embodiment, the jaw is formed from a 410 stainless steel sheet as a flat blank using a die-type punch. The formed blank is placed in a mold having a concave surface corresponding to the outer surface of the jaw cup and a recess in the concave surface corresponding to the closing cam. A punching tool having a convex surface corresponding to the inner surface of the jaw cup and a convex surface corresponding to the inner surface of the closing cam is pressed against the flat blank, and the jaw cup is cold-formed from the flat blank. In the present specification, some examples of the endoscopic multi-sample bioptom are described and illustrated. Although specific examples relating to the present invention have been described, it is not intended that the present invention be limited to these examples. The present invention is as broad as this technique allows, and the specification is intended to be read as such. Therefore, although the specific shape of the jaw cutting edge is disclosed, it will be understood that other types are also available. In particular, the cutting edge may be a toothed portion, a sharp edge without a toothed portion, or a combination of both. The teeth can be arranged in the radial direction or in another manner. Further, although the tip of the tubular sleeve is illustrated and described as having a knife-like sharp edge, a sleeve without a sharp edge can also be used with the jaw assembly of the present invention. In addition, although a particular shape has been described for the closing cam, it will be found that other shapes can be used. For example, instead of a closing cam that rises outward from the surface of the chin In addition, the jaw itself can be arranged so as to increase its diameter so that the outer diameter of the closed jaw cup is larger than the inner diameter of the cylinder at the position where the cam should be provided. In other words, the jaw cup can be arranged in a bulbous shape to enhance the closure of the cup by the tube and prevent the tube from moving too much on the jaw. In addition, the invention has described the advantage of allowing multiple biopsies without removal from the surgical site, but if desired, the device of the invention is used to perform one biopsy at a time. You can also do it. It will be appreciated by those skilled in the art that various modifications can be made to the inventions disclosed herein without departing from the spirit and claims of the present invention.