Biopsy forceps with tissue piercing member
A biopsy forceps device includes a control member; a yoke coupled to the member; jaws coupled to the yoke; and a capsule. In an open configuration, the jaws are separated to receive target tissue. In a closed configuration, cutting edges of the jaws are moved toward one another to cut tissue. The capsule slidably receives the yoke and a portion of the jaws. The jaws are constrained to the closed configuration when withdrawn proximally to a first position within the capsule. When the jaws are moved to a second position, portions of the jaws are freed from the constraint capsule and spread apart. When the yoke and the jaws are moved distally and the jaws move to the open configuration, a tissue contacting structure of the yoke extends distally to engage tissue between the jaws to anchor the engaged tissue again lateral movement as the jaws contact the tissue.
1. A biopsy forceps device, comprising:
a control member extending from a proximal end to a distal end;
a yoke coupled to a distal end of the control member, the yoke including a tissue contacting structure extending distally from a distal end of the yoke, wherein the tissue contacting structure is formed as a tissue penetrating spike;
first and second jaws coupled to the yoke, the first and second jaws being biased toward an open configuration, in which the first and second jaws are separated from one another to receive target tissue therebetween and being moveable to a closed configuration, in which cutting edges of the first and second jaws are moved toward one another to cut a portion of the target tissue from surrounding tissue, the first and second jaws defining a tissue receiving space therebetween to house the cut tissue; and
a capsule slidably receiving the yoke and a proximal portion of each of the first and second jaws, the first and second jaws being constrained to the closed configuration when withdrawn proximally to a first position within the capsule, and the first and second jaws being configured so that, when the first and second jaws are moved to a second position distal of the first position, distal portions of the first and second jaws are freed from the constraint of the capsule and spread apart from one another under their natural bias to the open configuration, the tissue contacting structure being positioned so that, when the yoke and the first and second jaws are moved distally and the first and second jaws move to the open configuration, the tissue contacting structure extends distally to engage a portion of tissue between the first and second jaws to anchor the engaged portion of tissue against lateral movement as the first and second jaws contact the tissue adjacent to the engaged portion of tissue,
wherein the yoke includes radially projecting portions that contact an inner surface of the capsule to center the yoke and the first and second jaws within the capsule, and
wherein the capsule includes a plurality of protrusions at a distal end of the capsule extending radially inward toward a longitudinal axis of the capsule to prevent the first and second jaws from sliding distally out of the capsule.
2. The device of claim 1 , wherein the first and second jaws include concave inner surfaces defining a hemispherical cup.
3. The device of claim 1 , wherein the first jaw is coupled to a first side of the yoke diametrically opposed, relative to a longitudinal axis of the capsule, to a second side of the yoke to which the second jaw is coupled.
4. The device of claim 3 , wherein the control member is non-rotatably coupled to the yoke and the yoke and the first and second jaws are rotatably received within the capsule so that, rotation of the control member rotates the yoke and the first and second jaws within the capsule.
5. The device of claim 1 , further comprising:
a handle which, during use of the device, remains outside a living body accessible to a user of the device, the handle including a first actuator operable to move the control member proximally and distally relative to the capsule and a second actuator to rotate the control member about a longitudinal axis of the capsule.
6. The device of claim 5 , further comprising:
a flexible elongated member extending from a proximal end coupled to the handle to a distal end coupled to the capsule, the elongated member receiving the control member therein.
7. The device of claim 6 , wherein the elongated member is sized to be slidably received within a working channel of an endoscope.
8. The device of claim 6 , wherein the elongated member is coupled to the capsule via a bushing.
9. The device of claim 6 , wherein the capsule is configured to rotate about the longitudinal axis of the capsule.
10. The device of claim 6 , wherein the elongated member is formed as a flexible coil.
11. The device of claim 1 , wherein an end effector including the first jaw, the second jaw, and the yoke has a length of less than 4 mm.
12. The device of claim 11 , wherein the end effector has a length no more than 3.5 mm.
13. The device of claim 1 , wherein the protrusions of the capsule are sized and shaped to meet the radially projecting portions of the yoke as the first and second jaws and the yoke move distally out of the distal end of the capsule.