PROBLEM TO BE SOLVED: To provide a treatment instrument for endoscopes, even when projection/retraction from/to a flexible sheath are repeated, being unlikely to deform the shape of a treatment part, and capable of reliably capturing concretion and polyp.SOLUTION: A treatment instrument for endoscopes includes: a long cylindrical flexible sheath 2 an operation wire 3 forward/rearward movably inserted in a cylinder of the flexible sheath 2 a basket part 4 as a treatment part, provided at a distal end of the operation wire 3, binding tip ends and rear ends of a plurality of elastic wires 5a-5d composed of a stranded wire, and formed to project/retract from/to the tip end of the flexible sheath 2 so as to be elastically contracted or spread and an operation part 10 provided at the rear end of the flexible sheath 2 and reciprocating the operation wire 3 for projecting/retracting the basket part 4 from/to the tip end of the flexible sheath 2. The elastic wires 5a and 5c are defined as S (left twist) stranded wires, while the elastic wires 5b and 5d are defined as Z (right twist) stranded wires, where the direction in which the stranded wire is twisted is inverse of the S stranded wires.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2018,JPO&INPIT【課題】可撓性シースからの突没を繰り返しても処置部の形状が歪みにくく、確実に結石やポリープを捕獲することのできる内視鏡用処置具を提供すること。【解決手段】長尺円筒状の可撓性シース2と、可撓性シース2の円筒内に進退自在に挿通される操作ワイヤ3と、操作ワイヤ3の先端に設けられ、撚り線からなる複数の弾性ワイヤ5a~5dの先端と後端とを結束し、可撓性シース2の先端から突没して弾性的に収縮または拡開するように形成した処置部であるバスケット部4と、可撓性シース2の後端に設けられ、バスケット部4を可撓性シース2の先端から突没させるために操作ワイヤ3の進退操作を行う操作部10とを有し、弾性ワイヤ5a、5cをS巻の撚り線とし、弾性ワイヤ5b、5dをS巻とは逆方向のZ巻の撚り線とした。【選択図】図1
