Endoscopic tissue collecting instrument

Claim 2

1 . An endoscopic tissue collecting instrument, comprising: a needle shaft having a needle tip and a tissue retaining recess behind the needle tip; and an outer sheath slidably fitted over the needle shaft, and having a distal end defining a blade, wherein when the outer sheath is moved relative to the needle shaft to cut off a tissue retained in the tissue retaining recess with the blade, at least a part of the blade generates a cutting force oblique relative to both a longitudinal axis direction of the outer sheath and a circumferential direction thereof.

Claim 3

2 . The instrument according to claim 1 , wherein the part of the blade is non-perpendicular to the longitudinal axis direction of the outer sheath.

Claim 4

3 . The instrument according to claim 1 , further comprising: a cam system which rotates the blade in the circumferential direction while moving the blade in the longitudinal axis direction.

Claim 5

4 . An endoscopic tissue collecting instrument comprising: a needle shaft having a needle tip pointed forward, and a tissue retaining recess recessed laterally in an area close to the needle tip; and an outer sheath fitted over the needle shaft so as to be movable back and forth in a longitudinal axis direction relative to the needle shaft, the outer sheath having a blade at its distal end for cutting off a tissue retained in the tissue retaining recess, wherein the blade formed at the distal end of the outer sheath is oriented obliquely relative to a circumferential direction of the outer sheath.

Claim 6

4 . An endoscopic tissue collecting instrument comprising: a needle shaft having a needle tip pointed forward, and a tissue retaining recess recessed laterally in an area close to the needle tip; and an outer sheath fitted over the needle shaft so as to be movable back and forth in a longitudinal axis direction relative to the needle shaft, the outer sheath having a blade at its distal end for cutting off a tissue retained in the tissue retaining recess, wherein the blade formed at the distal end of the outer sheath is oriented obliquely relative to a circumferential direction of the outer sheath.

Claim 7

5 . The instrument according to claim 4 , wherein a radially inner edge of the distal end of the outer sheath is saw-toothed to define the blade.

Claim 8

6 . The instrument according to claim 4 , wherein the distal end of the outer sheath is obliquely cut to define the blade.

Claim 9

7 . An endoscopic tissue collecting instrument comprising: a needle shaft having a needle tip pointed forward, and a tissue retaining recess recessed laterally in an area close to the needle tip; and an outer sheath fitted over the needle shaft so as to be movable back and forth in a longitudinal axis direction relative to the needle shaft, the outer sheath having a blade at its distal end for cutting off a tissue retained in the tissue retaining recess, wherein when the blade is moved across the tissue retaining recess, the outer sheath is rotated about the longitudinal axis direction while being moved in the longitudinal axis direction.

Claim 10

7 . An endoscopic tissue collecting instrument comprising: a needle shaft having a needle tip pointed forward, and a tissue retaining recess recessed laterally in an area close to the needle tip; and an outer sheath fitted over the needle shaft so as to be movable back and forth in a longitudinal axis direction relative to the needle shaft, the outer sheath having a blade at its distal end for cutting off a tissue retained in the tissue retaining recess, wherein when the blade is moved across the tissue retaining recess, the outer sheath is rotated about the longitudinal axis direction while being moved in the longitudinal axis direction.

Claim 11

8 . The instrument according to claim 7 , wherein the outer sheath is movably passed through a support tube to be fixed to an entrance of a treatment instrument insertion channel of an endoscope, and a tab projecting from a basal end portion of the outer sheath is in engagement with a spiral groove formed in the support tube.

Claim 12

9 . The instrument according to claim 8 , further comprising: a slider knob for manipulation to move the tab in the longitudinal axis direction.

Claim 13

10 . The instrument according to claim 8 , further comprising: a rotating knob for manipulation to rotate the tab about the longitudinal axis direction.

Claim 14

11 . The instrument according to claim 8 , further comprising: an aspiration channel extending through the needle shaft, and communicating with a rear of the tissue retaining recess.