JP2007275612A - Snare for removing tissue - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a snare for removing a tissue improved for removing a cancer tissue and a precancer tissue in digestive tracks. <P>SOLUTION: A conductive pull wire 39 is mounted to a wire loop 36 by a connector 37. The free end of the wire loop 36 is connected to a ferrule 40 joined to the distal end of a sheath type case 38. The wire loop 36 can be permanently bent at points 42 and 44. By it, when the pull wire 39 is pushed toward the distal end, a formed loop is positioned on a plane making an angle of nearly 90 degree in relation to the longitudinal axis of the sheath type case 38. When the loop is stretched, this arrangement is particularly effective when removing a [polyp] formed by the use of a ligature tool in contrast to a conventional snare in which the loop is positioned on the same plane as the longitudinal axis of the sheath type case. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  Diagnostic and therapeutic gastrointestinal endoscopes are commonly used to access the gastrointestinal tract for the purpose of observing and removing tissue. Typical endoscopic treatment procedures include cutting, peeling and removal by various known mechanisms.

Techniques for collecting tissue for biopsy include the use of forceps (with or without coagulation), snares, and the use of needles and brushes for cytology. These techniques achieve many diagnostic and / or therapeutic purposes, but may be insufficient. For example, there is currently no satisfactory method for removal of flat malignant mucosal lesions or lesions in submucosa. In some cases, deep test strips may be required for diagnosis (eg, lymphoma or Menetrie disease), and in such cases current methods are limited. Techniques such as “lift-cut” excision and polypectomy after injection of saline or glucose solution into the submucosal tissue have been used, but in some cases the tissue may not lift In some cases, these methods are not always successful because the implantation actually makes the region flat and makes tissue removal more difficult. These methods, known as endoscopic mucosal resection, are becoming more and more common, especially in Japan, where there are many early gastric cancers.
U.S. Pat. No. 4,735,194

  Early esophageal cancer is a major problem worldwide. By appropriate screening tests, diagnosis can be made when the disease is confined to the mucosa or at the precancerous stage. There are known methods (eg, laser photocoagulation) for the destruction of early esophageal cancer, but it effectively and completely removes tissue from patients with early esophageal cancer and other conditions as described above. There is a need for a way to make it possible.

  It is an object of the present invention to provide an improved tissue removal snare for removal of cancerous tissue and precancerous tissue in the gastrointestinal tract.

  According to the present invention, abnormal tissue in the gastrointestinal tract that is either cancerous tissue or precancerous tissue is identified. The abnormal tissue is then drawn into the distal end of the ligating instrument by suction and tied up to form an abnormal tissue polyp. The ligature is then removed from the endoscope and a cutting instrument such as a wire snare is introduced through the endoscope and used to cut polyps of abnormal tissue from surrounding healthy tissue .

  The present invention relates to a tissue removal snare that can be applied to any part of the digestive tract including the esophagus, stomach, and small intestine. For purposes of illustration, the present invention will be described with respect to preferred embodiments relating to the removal of mucosal lesions of the esophagus. In practicing the present invention, conventional ligatures and snares can be used, but in a preferred embodiment, specially constructed snares are used, as described below.

Elastic band ligation is a technique used to suppress bleeding in the digestive tract. For example, in the treatment of hemorrhoids or esophageal varices, mucosal and submucosal tissues are captured by elastic ligation bands, resulting in sphincter of the lesion, loss of necrosis, and eventual fibrosis. U.S. Patent No. 5,053,009 to Steigmann discloses a single band ligation instrument that has been commercially successful as a Steigmann-Goff Clearvue ^™ single band ligature. This Steigmann patent is hereby incorporated herein by reference.

A ligation device such as the Steigmann-Goff Clearvue ^™ ligature is effective in the treatment of esophageal varices and hemorrhoids where bleeding or bleeding prone vessels are isolated by ligation bands. However, ligation has not been used so far for the purpose of treating cancer or precancerous symptoms present in the gastrointestinal tract, where abnormal tissues tend to be flat and the usual ligation techniques cannot be easily performed .

  FIG. 1 shows a bendable endoscope 10 with a type of ligature that can be used to practice the present invention. The endoscope 10 includes a suction route 11 and a fiber optic illumination route 12, both exiting a distal end 13 connected to a control box (not shown) for supplying suction and illumination. The eyepiece 14 provides a means to view the ligation procedure directly or on the video camera and later video monitor images. The trip wire 15 located in the biopsy route 16 has a weighted handle 17 and is fixed to the inner tube 18 by a notch 19. The ligation ring 20 is installed on the inner pipe 18 at the notch 19. The ligation ring 20 is installed on the inner tube 18 located in the outer tube 21. The outer tube 21 is securely fixed to the endoscope 10 by a screw connection 22.

  In use of this instrument, the ligation ring 20 is secured to the forward end of the tube 18. A trip wire 15 exiting through the biopsy route 16 is attached to a notch 19 at the rear end of the tube 18 and this assembly is placed inside a tube 21 that is securely attached to the endoscope 10. As shown in FIG. 1, the tube 18 is installed in the tube 21 by a ring 20 that projects just beyond the end of the tube 21. The trip wire 15 exiting from the rear end of the endoscope 10 is pulled by a weighted handle 17.

  After placing the endoscope overtube on the patient, the instrument is introduced into the gastrointestinal tract. The instrument is advanced under direct vision until the target lesion is visualized and the tube 18 surrounds the intended target. When complete 360 ° contact is made, the suction force is activated to draw the lesion into the tube 18. Once the lesion is completely within the tube 18, the trip wire 15 is pulled and the ring 20 is slipped and secured around the base of the target lesion.

  2-8 show how mucosal resection is performed in the esophagus according to the present invention. The endoscope 10 is introduced into the esophagus at a position close to the area to be excised (FIG. 2). After the endoscope is placed, a conventional dye that a spray catheter 30 (FIG. 3) is introduced via the aspiration route 11 and the area 31 in question turns brown upon contact with tissue cells containing, for example, glycogen It is stained with Lugor iodine. Cancer and precancerous cells do not contain glycogen and therefore do not accept the dye. In this way, the abnormal tissue 31 can be identified endoscopically. After the area of interest has been stained, the spray catheter 30 is removed and an infusion catheter 32 (FIG. 4) is introduced via the endoscope's aspiration route 11. Inject saline (eg, 0.9% NaCl) into the stained area to lift it from the surrounding tissue of the esophagus (FIG. 5). Other materials such as glucose solutions can be used to lift the abnormal area.

  The infusion catheter 32 and endoscope 10 are removed from the patient's esophagus and a single fire ligature is secured to the distal end of the endoscope as shown in FIG. The endoscope is then reintroduced into the patient's esophagus so that the distal end of the ligature is close to the raised abnormal area (FIG. 6). A suction force is applied through the suction route 11 to draw the abnormal area into the ligature tool. Next, the trip wire 15 is pulled and the ligation ring 20 is applied around the base of the anomalous region so that when the ligature is removed, a tied mushroom-like polyp 34 is formed ( FIG. 7).

  The endoscope 10 is removed from the patient, and the ligature tool is removed from the endoscope. Insert the endoscope into the esophagus again. When a tied “polyp” is in view, a normal snare with wire loop 36 and sheath case 38 can be introduced through the biopsy route 16 of the endoscope. A snare is placed so that the wire loop surrounds the artificially created polyp (FIG. 8). When the wire loop 36 is drawn into the sheath mold case 38, the polyp is cut from the esophagus and cauterized. The polyp may be physically collected by a snare through an endoscope or released into the patient's digestive tract.

  The snare used in FIG. 8 may be conventional and may be, for example, a monopolar electrosurgical device that simultaneously cuts and cauterizes tissue such as polyps. In general, such snares include a wire loop that can be drawn into the sheath case, thereby allowing the loop to tighten around the polyp. By supplying the voltage, the polyp is cut and the wound is cauterized simultaneously.

  A snare distal end particularly adapted for use with the present invention is shown in FIG. The outer sheath of the snare is shown at 38 and the wire loop is shown at 36. A conductive pull wire 39 is attached to the loop 36 by a connector 37 that may be corrugated and soldered to the wire 39 and the adjacent end of the loop 36. Unlike a conventional snare, the free end of the wire 36 is connected to a small ferrule 40 that is joined to the distal end of the sheath case 38 by, for example, an adhesive. Wire loop 36 may be soldered to ferrule 40. Such an arrangement allows the loop 36 to be permanently bent at points 42 and 44 so that when the wire 39 is pushed distally (as shown in FIG. 9), the loop formed is sheathed. The mold case 38 is positioned on a plane having an angle close to 90 degrees with respect to the longitudinal axis. In contrast to a conventional snare where the loop is located in the same plane as the sheath case longitudinal axis when the loop is stretched, the arrangement of FIG. 9 is shown in FIGS. It is particularly effective in removing “polyps” formed by the use of one ligature. The handle at the proximal end of the snare may be conventional and therefore not shown.

  While preferred embodiments of the invention have been described above, the methods and apparatus described above are merely illustrative of the principles of the invention and depart from the spirit and scope of the claims. It will be understood that other methods and devices can be devised by those skilled in the art without departing.

It is a fragmentary longitudinal cross-sectional view of the endoscope ligation instrument of the present invention. FIG. 2 is a schematic diagram of a mucosal resection procedure according to a preferred embodiment of the present invention. FIG. 2 is a schematic diagram of a mucosal resection procedure according to a preferred embodiment of the present invention. FIG. 2 is a schematic diagram of a mucosal resection procedure according to a preferred embodiment of the present invention. FIG. 2 is a schematic diagram of a mucosal resection procedure according to a preferred embodiment of the present invention. FIG. 2 is a schematic diagram of a mucosal resection procedure according to a preferred embodiment of the present invention. FIG. 2 is a schematic diagram of a mucosal resection procedure according to a preferred embodiment of the present invention. FIG. 2 is a schematic diagram of a mucosal resection procedure according to a preferred embodiment of the present invention. FIG. 3 is a cross-sectional view of the distal end of a snare according to a preferred embodiment of the present invention.

Explanation of symbols

10 Endoscope
11 Suction route
20 Ligation ring
30 spray catheter
31 Abnormal tissue
32 infusion catheter
34 Polyp
36 wire loop
37 connectors
38 sheath type case
42, 44 points

Claims (7)

An elongate sheath case, a elongate member configured to transmit force in a distal direction, and a loop coupled to the distal end of the elongate member;
The tissue is configured such that when the elongate member is pushed in the distal direction, the loop is positioned on a plane having an angle of approximately 90 degrees with respect to the longitudinal axis of the sheath case. Removal snare.   2. The tissue removal snare according to claim 1, wherein the elongate member exists in the sheath type case.   2. The tissue removal snare according to claim 1, wherein the elongated member has a wire.   The tissue hoof according to claim 3, wherein the wire is electrically conductive and is attached to the loop by a connector.   5. The tissue removal snare according to claim 3, wherein a free end of the loop is connected to a distal end of the sheath type case.   When the long member is pushed distally and the loop is positioned in a plane at an angle of approximately 90 degrees with respect to the longitudinal axis of the sheath case, the loop is permanently at one or more points. 6. The tissue removal snare according to any one of claims 1 to 5, wherein the snare is bent to assist the loop.   7. The tissue removal snare according to claim 6, wherein the wire is permanently bent at two points.

Images