Endoscopic treatment tool

Patent metadata

Field	Value
Publication number	US-9301800-B2
Application number	US-201113025562-A
Country	US
Kind code	B2
Filing date	Feb 11, 2011
Priority date	Aug 13, 2008
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

The present invention relates to a flex-knife that enables a technique such as tissue excision to be carried out more easily, and is provided with: a rod-shaped high frequency knife which is endoscopically inserted into a body cavity and is for performing cutting procedures; a wire, the high frequency knife connected to the front end thereof; a sheath consisting of an insulating material, into which the wire is inserted; a main body, the back end of the sheath being connected thereto; and a slider to which the back end of the wire is fixed and which is disposed to the main body to enable sliding in the axial direction; wherein the high frequency knife has a large diameter part at its distal end, the large diameter part having an outer diameter that is larger than the inner diameter of the sheath.

First claim

What is claimed:

1. A treatment tool comprising:
a cutting section which is adapted to be endoscopically inserted into a body cavity and performs cutting procedures by transforming high frequency current, the entirety of the cutting section being conductive;
a wire connected to the cutting section at a distal end of the wire;
a sheath comprising an insulating material, the wire being inserted into the sheath;
a main body, a back end of the sheath being connected to the main body; and
a slider to which a back end of the wire is fixed and which is disposed to the main body to enable sliding in an axial direction of the sheath,
wherein the cutting section has a large diameter part at a distal end of the cutting section and a small diameter part proximal to the large diameter part, the large diameter part having an outer diameter such that the large diameter part is not capable of being accommodated in the sheath when the cutting section is maximally retracted along the axial direction toward the back end of the sheath,
wherein the large diameter part includes at least a first portion and a second portion, the first portion at least partially including a circular cross-section formed in a direction orthogonal to a longitudinal axis of the cutting section at a distal end of the small diameter part and the second portion at least partially including a first rounded surface conductively connected to a circumference of the first portion, the second portion being disposed at a distal end of the first portion,
wherein a tubular distal member having insulating properties is disposed on a distal end of the sheath, the tubular distal member including an insertion portion that is inserted into the sheath and a tip that is exposed outside the sheath,
wherein the tip at least includes a second rounded surface, a radius of curvature of the second rounded surface being larger than that of the first rounded surface, and
wherein when the cutting section is maximally retracted along the axial direction toward a proximal end of the sheath, a proximal surface of the second portion contacts with a distal end of the tip such that the large diameter is restricted to not to be accommodated in the sheath, the first rounded surface being more distal than the second rounded surface.

2. The treatment tool according to claim 1 , wherein the first rounded surface of the second portion has a semispherical shape formed such that an apex of the semispherical shape is located on the longitudinal axis of the cutting section.

3. The treatment tool according to claim 2 , wherein
the first portion is cylindrical and is provided to a proximal end side of the semispherical shape of the second portion so that an axis of the cylindrical first portion is parallel to an axis of the cutting section.

4. The treatment tool according to claim 1 , further comprising:
the tubular distal member which has a through hole along the axis of the cutting section,
wherein a diameter of the through hole is smaller than the outer diameter of the large diameter part.

5. The treatment tool according to claim 4 , wherein the outer diameter of the large diameter part is smaller than an outer diameter of the tip of the tubular distal member.

6. The treatment tool according to claim 5 , wherein the outer diameter of the large diameter part is half the size of the outer diameter of the tip of the tubular distal member.

7. The treatment tool according to claim 4 , wherein an outer diameter of the tubular distal member is larger than an outer diameter of the sheath.

8. The treatment tool according to claim 1 , wherein the large diameter part has an outer diameter that is larger than an inner diameter of the sheath, the large diameter part projects out in the radially outward direction approximately 0.1-0.15 mm more than the outer peripheral surface of the small diameter part, and the small diameter part has a diameter of approximately 0.3-0.5 mm.

Assignees

• Suzuki Tetsu
• Yahagi Naohisa
• Olympus Corp

Inventors

• Suzuki Tetsu
• Yahagi Naohisa

Classifications

• A61B1/005

  Flexible endoscopes · CPC title

• A61B2018/00601

  Cutting · CPC title

• A61B2018/00482

  Digestive system · CPC title

• A61B2018/1475

  Electrodes retractable in or deployable from a housing · CPC title

• A61B2018/1417

  Ball · CPC title