Patent Application
20200029993
The present invention relates to a tissue excision instrument for excising a part of body tissue including skin.
In medical sites, tissue excision instruments for excising or sampling a part of body tissue (hereinafter, referred to merely as “tissue” in this specification) have been used for the purpose of diagnosing, curing, or examining the tissue including skin of a living body.
For example, such a tissue excision instrument has a cylindrical blade edge, and a user excises a part of tissue with the blade edge (see, for example, Patent Document 1).
As illustrated in
However, when the annular blade edge is pressed against the tissue, pressing force caused by the pressing operation of the handle part 101 is dispersed circularly, so that the force of appropriate magnitude is required for resisting elasticity of the tissue, resulting in difficulty in operation.
In order to cope with this, a tissue excision instrument is proposed in which the tip flat surface of the blade edge of the blade part 102 perpendicular to the axial direction of the handle part 11 is inclined as illustrated in
However, in the case of the excision instrument illustrated in
Further, in the case of the excision instrument illustrated in
The present invention has been made in view of the problems of the conventional techniques, and the object thereof is to provide a tissue excision instrument having an improved cutting quality of the annular blade edge.
To solve the above problems, according to the present invention, there is provided a tissue excision instrument in which the tip of a cylindrical blade part is pressed against tissue to excise the tissue extracted and led into the cylinder of the blade part, wherein a plurality of curved parts having arc-shaped irregularities are uniformly formed on the circumference of an annular-shaped blade edge of the blade part. In this case, the curvatures of the arc-shapes of the respective curved parts are preferably the same.
By providing a pushing part that is axially moved inside a hollow of the blade part to protrude outside from the blade part, it is possible to easily remove a tissue slice adhering to the inside of the blade edge after excision.
Further, in a tissue excision instrument having a punching part configured to protrude from and retract into the inside of the blade edge, it is preferable to provide, around the end face of the punching part that faces the blade edge, a second blade part that contacts the inside of the blade edge when the punching part is moved down.
In the tissue excision instrument according to the present invention, when the blade part pressed against the tissue is rotated, a plurality of arch-shaped irregularities provided on the annular-shaped blade edge of the blade part act as arches, so that the tissue is finely excised, and operability is enhanced.
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The annular-shaped blade edge 3A has three curved parts 4 provided at equal intervals along the circumference. The curved parts 4 are irregularities which are formed along the axial direction of the blade part 3 by arc-shaped gentle curves, by which a plurality of arches are formed on the circumference of the blade edge 3A. In this case, the arches, i.e., the arc-shaped curved parts 4 preferably have the same curvature.
By providing the curved parts 4 that form the arches on the blade edge 3A, it is possible to form a smooth cut in the tissue by the arch which is a gentle curved portion of the curved part 4 extending from a peak 4p to a valley 4r of the curve when the blade edge 3A is pressed perpendicularly against a tissue surface. In order to form such an arch on the circumference of the blade edge 3A, it is necessary to determine the maximum number of the curved parts 4 to be provided on the blade edge 3A in accordance with the diameter of the annular ring of the blade edge 3A. In this example, the diameter of the annular ring of the blade edge 3A is 6 mm. In this case, up to four curved parts 4 can be provided. However, when the number of the curved parts 4 is equal to or larger than 4, the arch cannot be formed on the circumference of the blade edge 3A, that is, the blade edge has a corrugated shape as illustrated in
The handle part 1 is a part that a user holds when using the tissue excision instrument 10 and is a straight rod-like member made of metal or resin. The handle part 1 is subjected to knurling or satin treatment so as to prevent slipping of a hand of a user when he or she holds the handle part 1.
The blade holder 2 is a member which is integrated with the blade part 3. Specifically, at the time of manufacturing, the blade part 3 is loaded into a die, and then molten resin is injected to wrap the blade part 3, followed by solidification of the molten resin. In this case, the handle part 1 may also be made of the same resin and molded integrally with the blade holder 2 in the die.
In the thus configured tissue excision instrument 10, the cylindrical blade part 3 is pressed against the tissue, and the handle part 1 is rotated. With the rotation of the handle part 1, the blade part 3 is rotated. Then, in the blade edge 3A, by the arch formed by a part of each of the curved parts 4 extending from the peak 4p to the valley 4r, a cut having a uniform depth can be formed in the tissue along the circle of the blade edge 3A. At this time, by the plurality of arches provided at equal intervals, the rotation of the handle part 1 is transmitted smoothly to the blade part 3, enhancing operability.
A tissue slice extracted and led into the cylinder of the blade part 3 and excised there adheres to the inside of the blade edge 3A. Then, the tissue excision instrument 10 is separated from the tissue. In this manner, the tissue slice can be excised from the tissue and sampled.
The thus configured tissue excision instrument 10 is used for an operation such as removal of a mole or sampling of a part of tissue as an inspection sample.
In the tissue removal process using the above tissue excision instrument 10, there may be a case where it is necessary to insert tweezers or the like into the blade part 3 in order to remove the excised tissue slice adhering to the inside of the blade edge 3A. Such a removal operation takes labor and, in particular, when the diameter of the annular ring of the blade edge 3A is small, the removal operation is very troublesome.
The following describes an embodiment of the tissue excision instrument capable of quickly removing the tissue slice adhering to the inside of the blade edge.
A tissue excision instrument 20 illustrated in
The pushing member 7 is a resin integral molding and constituted of a rod-like shaft body 11, a pushing part 12, and a lock part 13 as illustrated in
The cover part 6 has two lock holes 15 and 16 one of which is engaged with the protrusion 14 of the lock part 13 when the pushing member 7 is inserted into the cylinder.
The blade part 5 is formed integrally with the cover part 6. Specifically, at the time of molding, the blade part 5 is loaded into a die, and then molten resin is injected to wrap the blade part 5, followed by solidification of the molten resin.
The annular-shaped blade edge 5A has a plurality of curved parts 9 provided at equal intervals along the circumference. The diameter of the annular ring at the tip of the blade edge 5A in this example is set to 3 mm. When the diameter of the annular ring is set to such a small value, the maximum number of the curved parts 9 each having an arc-shaped gentle curve is set to about three (
Normally, as illustrated in
To collect the tissue slice adhering to the inside of the blade edge 5A, the protrusion 14 is pushed and, at the same time, the rear end of the pushing member 7 is pushed in such a way that the pushing member 7 is moved toward the blade edge 5A against the spring force of the spring member 8. As a result, the locking state between the protrusion 14 of the lock part 13 and the lock hole 15, which is held by the elastic force of the lock part 13 itself, is released, and the lock part 13 moves inside the cover part 6. Then, when the protrusion 14 reaches the lock hole 16, the lock part 13 is returned in a direction separated from the shaft body 11 by its own elastic force, and the protrusion 14 is locked into the lock hole 16.
When the pushing member 7 is moved until the protrusion 14 is locked into the lock hole 16, the pushing part 12 protrudes outward from the tip of the blade part 5 as illustrated in
The following describes an embodiment of a puncher 30 which is a tissue excision instrument used for punching a hole in a blood vessel during medical operation.
The outer case 17 has, on both side faces thereof, a finger hook 32 having a hole through which a finger of an operator is inserted. The blade part 18 has an annular-shaped blade edge 18A at the tip thereof, and the blade edge 18A has three curved parts 21 provided at equal intervals along the circumference. As illustrated in
The punching part 19 having a columnar body has a circular-cone-shaped pointed head part 19A at the tip thereof. The end portion of the punching part 19 on the side opposite to the pointed head part 19A is fixedly supported to the outer case 17 by a pin 31. The blade part 18, together with the punching part 19, is also supported by the outer case 17 by means of the pin 31.
The blade part 18 has an elongated hole 18B extending in the longitudinal direction thereof, and the pin 31 is slidably fitted into the elongated hole 18B. The pin 31 is biased by a spring 24 and is normally locked to the lower portion of the elongated hole 18B. In this state, as illustrated in
In this state, an operator presses the entire puncher 30 against a blood vessel to cause the tip of the punching part 19 to rush into the blood vessel while breaking through the blood vessel surface with the pointed head part 19A. Then, when the operator manually pushes down the upper end of the blade part 18 against the biasing force of the spring 24 while holding the outer case 17 at the finger hook 32, the blade part 18 is moved until the pin 31 is locked to the upper portion of the elongated hole 18B and, as illustrated in
While the embodiments of the present invention have been described, the present invention is not limited to the above embodiments. Various modifications can be made based on the technical idea of the present invention, and the present invention does not exclude such modifications. For example, the curvatures of the arc-shapes of the respective curved parts 4 need not be the same as long as the arches are ensured. Further, the blade edge may be internally sharpened such that the diameter of the inner peripheral surface thereof is reduced more toward the tip relative to the diameter of a blade part body.
The present invention relates to a tissue excision instrument used for medical purposes, such as diagnosis, curing, or examination of a living body and has industrial applicability.
