Abstract: This treatment tool for biopsy includes a needle tube, which having a first aperture and a second aperture. The first aperture and the second aperture communicate with the tubular space. The second aperture is provided in a side surface of the needle tube at more proximal end side than the first aperture. In a cross-section of the second aperture, a distal end circular arc portion of an end surface of the second aperture has a distal end side inclined surface that is inclined so as to be positioned gradually outwards of a radial direction of the needle tube towards the distal end side, and a proximal end circular arc portion of the end surface of the second aperture has a proximal end inclined surface that is inclined so as to be positioned gradually outwards of the radial direction of the needle tube towards the proximal end side.

Abstract: A treatment instrument that is inserted in a freely advancing and retracting manner into the a channel of an ultrasonic endoscope that includes an ultrasonic scanning mechanism emitting and receiving ultrasound waves, the first dimple includes a first area which has a reflecting surface that reflects the ultrasound waves emitted from the ultrasonic scanning mechanism to the ultrasonic scanning mechanism; and a second area which is arranged contiguously to the first area at a proximal end side of the first area and which includes a wall surface on which the ultrasound waves that is emitted toward the first area in a direction to travel directly from the ultrasonic scanning mechanism cannot be incident.

Abstract: This treatment tool for biopsy includes a needle tube, which having a first aperture and a second aperture. The first aperture and the second aperture communicate with the tubular space. The second aperture is provided in a side surface of the needle tube at more proximal end side than the first aperture. In a cross-section of the second aperture, a distal end circular arc portion of an end surface of the second aperture has a distal end side inclined surface that is inclined so as to be positioned gradually outwards of a radial direction of the needle tube towards the distal end side, and a proximal end circular arc portion of the end surface of the second aperture has a proximal end inclined surface that is inclined so as to be positioned gradually outwards of the radial direction of the needle tube towards the proximal end side.

Abstract: A treatment instrument that is inserted in a freely advancing and retracting manner into the channel of an ultrasonic endoscope, includes a treatment member that has a distal end and a proximal end and an outer surface that is a circular cylindrical shape in which a plurality of dimples are formed indenting into the outer surface. The length component that is measured in the direction of the center axis of the treatment member and which is the distance between the rear edge, which is positioned closest to the proximal end, and the deepest part of the dimple is shorter than the length component that is measured in the direction of the center axis and which is the distance between the front edge which is closest to the distal end and the deepest part.