Treatment accessory for endoscope

Abstract: The present invention relates to an accessory for an endoscope, comprising a tube, said tube being provided with a meshed member comprising a net at the distal end thereof, wherein a plurality of openings are defined as meshes of said meshed member, said net being connected to the distal end of said tube, covering an opening at the distal end of said tube and being retractable inside said tube through said opening.

Description: The present invention relates to a treatment accessory for an endoscope capable of aspirating liquids or other material. When using an endoscope it is usually important to ensure that the area around an affected area in a body cavity is clean and easily visible. As such, treatment accessories are provided for insertion in a channel of the endoscope which aspirate liquids, such as the cleaning liquid, dye, blood or the like, and which collect particles such as food residue and the like. A conventional treatment accessory for aspiration is a flexible tube with an aspiration opening at a distal end thereof. A conventional treatment accessory for collecting particles is provided, at a distal end thereof, with a basket-like collector which is formed from a plurality of wires. In operation, the collector is extended from a distal end of the channel and the collector expands resiliently to an open state, a particle to be collected is then positioned in the collector and the collector is drawn into the channel to capture the particle. Generally, the aspiration treatment accessory and the collecting treatment accessory must be used separately. Thus, the collecting treatment accessory must first be used to collect large particles, then, the collecting treatment accessory is removed and the accessory or the aspiration treatment accessory is inserted. Thereafter, for example, the aspiration treatment accessory is used to aspirate the liquid. Further, if the liquid to be aspirated still includes particles which are larger than the aspiration opening of the aspiration treatment accessory, the aspiration treatment accessory may become clogged and have to be removed and cleaned during the aspiration operation. The conventional collecting treatment accessory has the further problem. That is, since the collector is generally made of thin wires, the resilient force generated to expand the collector after being extended from the channel of the endoscope is relatively weak and may not be sufficient to overcome the stickiness of certain kinds of mucous or the like. Also, the formation of the collector using thin wires may require specialized tools-and due to the bundling of the wires to form the collector, the collector may be too large to fit into a narrow channeled endoscope. The cleaning of an affected area is particularly important when an affected area is to be treated by cauterization or the like. Cauterization is performed to stop various kinds of internal bleeding, such as bleeding from tumorous areas of the digestive tract or bleeding caused by treatment accessories or the like. Cauterization is performed using a treatment accessory provided with a laser probe, a heat probe, a high-frequency probe, a microwave probe or the like, mounted at the end of a flexible sheath. An accessory for an endoscope according to the preamble of claim 1 is known from US 4,650,466. This accessory is an angioplasty device comprising a woven tube of metal or plastic fibers and a retraction stylet that are attached at one end to a catheter tube. It is therefore an object of the present invention to provide an improved treatment accessory for an endoscope which has a simple structure and which is less likely to clog during aspiration. It is a further object of the present invention to provide an improved treatment accessory for an endoscope which has a simple structure and which, if clogged, can be operated to remove the clogging without removal from the endoscope. For the above objects, there is provided an accessory for an endoscop according to claim 1. According to the invention, there is provided an accessory for an endoscope, including a tube, a meshed portion is provided at the distal end of the tube, a plurality of openings being defined as meshes of the meshed member. The meshed portion may be another element connected to the tube, or a part of the tube which is formed to have meshes. In the former case, the meshed member comprises a net that is connected to the distal end of the tube, covering an opening at the distal end of the tube. The net is retractable inside the tube through the opening at the distal end of the tube. If the net is retractable, when aspiration is performed, the net is protruded from the tube, and therefore an object may not enter the tube. Further, if some substance clogs on the net, by reciprocally retracting and protruding the net, the substance may be removed from the net It should be noted that even if the net is not retractable, clogging may be prevented effectively. Optionally, the accessory as above is further provided with a connector portion provided at a proximal end of the tube, an external device being connected with the connector portion. To the connector portion, for example, a device for aspirating fluid, a device for dispersing coloring pigment, or the like can be connected. Preferably, the connector includes a mouthpiece coupled to the tube. According to one preferred embodiment the mouthpiece is provided coaxially with the tube. The distal end of the wire is connected to the net so that the net is movable between a position at which the net is retracted and another position at which the net is protruded from the distal end of the tube, in accordance with operation of the wire. Optionally, the mechanism comprises a stopper for arresting the wire at least one predetermined position along a movable range in the axial direction of the wire. Preferably, the predetermined position is a position at which the net is protruded from the distal end of the tube. Brief Description of the Drawings Fig. 1 is a sectional side view of a treatment accessory according to an embodiment of the invention; Fig. 1A shows a groove formed on the treatment accessory shown in Fig. 1; Fig. 2 is a sectional side view of the treatment accessory of Fig. 1 in different state; Fig. 2A shows a groove formed on the treatment accessory shown in Fig. 2; Fig. 3 is a schematic drawing showing use of the treatment accessory of Fig. 1; Fig. 4 is a side view of a distal end of the treatment accessory of Fig. 1 in use; and Fig. 5 is a side view of a distal end of the treatment accessory of Fig. 1 when dislodging clogging particles. Fig. 1 shows a treatment accessory 90 according to an embodiment of the invention. The treatment accessory 90 includes a flexible tube 911 and a cylindrical manipulation portion 720 coaxially attached at a proximal end of the flexible tube 911. The flexible tube 911 is made of, for example, nylon, HDPE (polyethylene), polyurethane resin or tetrafluoroethylene resin, and is designed to be flexible, at least at a distal end portion thereof. When using the treatment accessory 90, the flexible tube 911 is inserted through an insertion channel of an endoscope (not shown). As shown in Fig. 1, a proximal end of a wire 13 is also attached to the manipulation portion 720 and the wire 13 extends through the entire length of the flexible tube 911. In particular, the diameter of the wire 13 is sufficiently small with respect to the inner diameter of the flexible tube 911 to allow a liquid or the like to flow along the length of the flexible tube 911. Further, as shown in Fig. 1, a connection mouthpiece 24 which may be connected to an external apparatus (not shown) is formed at a proximal end of the manipulation portion 720 and a passage 25 is provided through the manipulation portion 720 to connect the connection mouthpiece 24 with the flexible tube 911. In this embodiment, the manipulation portion 720 includes an outer cylinder 21 to which the base end of the flexible tube 911 is connected and an inner cylinder 22 to which the base end of the wire 13 is connected and which is slidably arranged coaxially with the outer cylinder 21. Thus, the wire 13 is axially movable with respect to the flexible tube 911 by moving the inner cylinder 22 with respect to the outer cylinder 21. An O-ring 23 is mounted between the outer cylinder 21 and the inner cylinder 22 to provide a liquid seal. In this embodiment, the connection mouthpiece 24 is formed at a proximal side of the inner cylinder 22 and the passage 25 is provided through the inner cylinder 22 providing a fluid path to the flexible tube 911. As shown in Figs. 1 and 1A, an L-shaped groove 27 is formed on an outer surface of the inner cylinder 22 and a pin 28 protrudes inward from the outer cylinder 21 to engage with the groove 27. The groove 27 and the pin 28 are arranged such that, when the pin 28 is engaged with a lateral part 27a of the groove 27, the inner cylinder 22 is not axially movable. In this embodiment, a distal end portion of a flexible tube 911 is provided with at least one aspiration opening 912. In this case, the aspiration opening 912 is at the distal end of the flexible tube 911. The flexible tube 911 is also provided with an expandable and contractible mesh filter 914 mounted at the distal end portion of the flexible tube 911 such that the aspiration opening 912 is covered thereby. The mesh filter 914 is, for example, a mesh tube formed by braiding thin wires, for example, stainless steel, into a mesh. One end of the mesh tube is tightly bound to the distal end of the wire 13 and the other end is then folded back and tightly bound to a circumferential surface of the flexible tube 911 such that the aspiration opening 912 is covered by the mesh filter 914. The wire 13, the flexible tube 911, and the mesh filter 914 are arranged such that the mesh filter 914 may be expanded by extending the wire 13 from the distal end of the flexible tube 911, as shown in Fig. 1, and retracted into the flexible tube 911 (in this case, through the aspiration opening 912) by drawing the wire 13 into the flexible tube 911, as shown in Fig. 2. In use, the treatment accessory 90 is inserted through the channel of the endoscope with the mesh filter 914 drawn into the flexible tube 911 and then, when protruded from the channel and inserted into the liquid L or the like in a body cavity, the mesh filter 914 is extended from the distal end of the flexible tube 911 (as shown in Fig. 3). With this arrangement, even if particles, such as food residue and the like, in the liquid L are drawn toward the aspiration opening 912, since the mesh filter 914 has a relatively large area, the aspiration opening 912 is not clogged. Further, if particles clog the mesh filter 914 during the aspiration of the liquid L, the dogging can be eliminated by reciprocating movements of the wire 13 (i.e., the inner cylinder 22) along the axis to deform the mesh filter 914, as shown in Figs. 4 and 5, to dislodge any particles or the like. As described above, there is provided an improved accessory for an endoscope which has a simple structure and which is less likely to clog during aspiration. Further, a treatment accessory having a simple structure and which, if clogged, can be operated to remove the clogging without removal from the endoscope is provided.

Claims: An accessory (90) for an endoscope, comprising a tube (911), said tube (911) being provided with a meshed member (914) comprising a net (914) at the distal end of said tube (911), wherein a plurality of openings are defined as meshes of said net (914), said net being connected to the distal end of said tube (911), covering an aspiration opening (912) at the distal end of said tube (911), characterized in that said net is retractable inside said tube (911) through said aspiration opening (912), wherein the distal end of a wire (13) is connected to said net so that said net is movable between a position at which said net is retracted inside said tube and another position at which said net is protruded from the distal end of said tube (911), in accordance with operation of said wire. The accessory (90) according to claim 1, further provided with a connector portion provided at a proximal end of said tube (911), an external device being connected with said connector portion (24). The accessory according to claim 2, wherein said connector portion includes a mouthpiece (24) coupled to said tube (911), said mouthpiece (24) receiving a connecting portion of said external device. The accessory according to claim 3, wherein said mouthpiece (24) is provided coaxially with said tube (911) or is substantially perpendicular to the axis of said tube (911). The accessory according to any one of the preceding claims, comprising a stopper (28) for arresting said wire (13) at at least one predetermined position along a movable range in the axial direction of said wire (13). The accessory according to claim 5, wherein said predetermined position is a position at which said net is protruded from the distal end of said tube (911).

Inventors: OUCHI TERUO, OUCHI, TERUO, Ouchi, Teruo, c/o Asahi Kogaku Kogyo K. K.
Applicants: PENTAX CORP, PENTAX CORPORATION
Application year: 1997
Main classification: A61B18
IPC codes: A61B17, A61M25, A61B18, A61B19