JPH0277245A - Shape-memory action body - Google Patents

Abstract

PURPOSE:To cause an unnecessary waviness in the course of a restoration deformation to be small and to execute a safe use even in a narrow cavity by stagedly restraining the shape restoring action of a formed storage element. CONSTITUTION:A sheath 3 and a water feed port 13 are liquid-tightly communicated. A water feed tube is connected to the water feed port 13, and a heated physiological salt water can be supplied from a water feeding means. A tip part 4b of a wire 4 for gripping is storage-processed so as to be made into a loop shape in a high temperature phase, namely, in a heated condition. It is set so as to be in a linear shape in a low temperature phase. The sheath 3 is penetratingly inserted into a channel for a penetrating insertion and introduced into a body cavity, for example, a bile duct 17. It is inserted so as to be beyond a stone 18 to the stone 18 in the bile duct 17. In such a condition, a hot water is continuously supplied from the water feed port 13. The hot water is heated at a temperature higher than the shape restoration temperature (transformation temperature) of the wire 4 for gripping by several degrees, and moreover, it is set at the temperature harmless to an organism.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a shape memory operating body such as an instrument operated using a shape memory material.

BACKGROUND OF THE INVENTION For five years now, medical devices have been provided that utilize shape memory alloys to operate to restore shape within a body cavity. For example, Japanese Patent Application Laid-Open No. 62-82976 and USP 4,512
, 338, JP-A-62-
There is a thrombus removal device known from Japanese Patent No. 49841.

The common technical means for these methods is to memorize a complicated shape in a shape memory alloy wire and then deform it into a straight line. Then, after inserting it into a blood vessel, it is heated by a heating means and restored to its memorized shape.

[Problems to be Solved by the Invention] It is true that the above-mentioned conventional device can be inserted into a body cavity in a straight state and restored to a complicated shape after insertion, but the memorized shape is long and To some extent,
In the process of recovery and deformation from a straight state, the body cavity tends to undulate in an unnecessary range, resulting in unnecessary movement, which may cause damage to the body cavity wall, etc. This was particularly a problem within narrow body cavities.

The present invention has been made with attention to the above-mentioned problems, and its purpose is to have a relatively simple structure, but to reduce unnecessary waviness during the process of recovery deformation from a straight state, and to reduce unnecessary waviness even in a narrow cavity. An object of the present invention is to provide a shape memory operating body that can be used safely.

[Means and operations for solving the problems] In order to solve the above problems, the present invention provides a shape memory operating body that is operated using a shape memory element that restores a memorized shape by heating means, in which the shape memory element recovers its shape. This system provides a means to restrict the number of people in stages.

Therefore, in the process of restoring the memorized shape by the heating means, the shape memory operating body is restrained in stages and deformed sequentially, so that unnecessary waviness and the like can be suppressed as much as possible.

Therefore, even in a narrow cavity, a stable shape recovery operation can be performed without causing any damage to the surroundings.

[Embodiment] FIGS. 1 to 6 show a first embodiment of the present invention. This embodiment is an example applied to a stone removal tool 1. As shown in FIG. 1, the stone removal tool 1 consists of an operating section 2 and a sheath 3 that is inserted into a body cavity. The sheath 3 is formed from an elongated flexible resin tube or a tightly wound coil,
It can be inserted into the insertion channel of an endoscope, and even if the insertion portion of the endoscope is curved, it can be inserted through the insertion channel.

A grasping wire 4 made of a shape memory alloy is inserted into the inside of the sheath 3 . This grasping wire 4 is folded in two and is provided so as to be able to protrude and retract from the distal end of the sheath 3 with the folded portion 4a side as the distal end. An operating pipe 5a is fitted to the proximal end of the wire 4, and the drive transmission member 5
It consists of This drive transmission member 5 is connected to a slider 6, which will be described later.

The operating section 2 is formed by connecting an operating section main body 7 with a guide member 8 that fits and guides the slider 6, and the operating section main body 7 and the guide member 8 are connected via a connecting member 9. A guide groove 10 is formed in the guide member 8 to accommodate the rear end side of the drive transmission member 5. A ring-shaped finger rest portion 11 is formed at the rear end of the guide member 8. As shown in FIG. Further, the slider 6 is also formed with a finger rest portion 12.12. By moving the slider 6 back and forth, the gripping wire 4 can be moved forward and backward. Further, a water inlet 13 is formed on the side surface of the operation section main body 7, and this water inlet 13 communicates with the inside of the sheath 3 through a space inside the operation section 2. Further, an O-ring 14 is provided on the inner surface of the operating section main body 7 on the rear end side of the water supply port 13 . This O-ring 14 contacts the outer periphery of the drive transmission member 5 and seals it liquid-tightly. The sheath 3 is fitted onto the outer periphery of a cylindrical portion 15 formed at the front end of the operating section main body 7 and is fixed airtightly by adhesive or the like. Thus, the sheath 3 and the water supply port 13 are in liquid-tight communication. A water supply tube (not shown) is connected to the water supply port 13 so that heated physiological saline can be supplied from the water supply means. In this case, when the sheath 3 is formed from a tightly wound coil, it is preferable to fit a waterproof tube into either the inside or outside of the sheath 3.

The distal end portion 4b of the gripping wire 4 is subjected to high temperature heating (matrix phase), that is, it is memorized so that it forms a loop shape as shown in FIG. 3 in the heated state.

Then, in the low temperature phase, it is set to be linear.

Next, the operation of the calculus remover 1 having the above structure will be explained. First, as shown in FIG. 4, with the grasping wire 4 drawn into and housed inside the sheath 3, the sheath 3 is inserted into the insertion channel of the endoscope 16 and inserted into the body cavity, for example, as shown in FIG. 5-a. It is introduced into the bile duct 17 as shown in . Then, it is inserted into the stone 18 in the bile duct 17 so as to go over the stone 18. In this state, hot water is continuously supplied from the water supply port 13. This hot water is
It is heated to a temperature higher than the shape recovery temperature (transformation temperature) of the body, and is set at a temperature that is not harmful to living organisms. Therefore, the gripping wire 4 made of a shape memory alloy that comes into contact with the hot water transforms into a high-temperature phase, but since it is housed within the sheath 3, it remains restrained in a straight line.

Next, when the slider 6 is slid forward in the operating section 2, the tip of the grasping wire 4 is moved from the tip of the sheath 3 to the fifth -
b Push it out as shown in figure. Since this protruding portion is no longer constrained by the sheath 3, it immediately deforms into the memorized shape.

Then, it curves along the front surface of the stone 28. Furthermore, when the slider 6 is pushed forward, as shown in FIG. 5-b to FIG. 5-c and FIG. 5-d, it protrudes greatly and curves greatly. Then, as shown in Figure 5-d, the stone 28 extends from the front surface to the near side of the stone 28.
8 to securely capture the stone 28. Thus, the sheath 3 constitutes a means for stepwise restraining the shape recovery operation of the gripping wire 4, which is a shape memory element.

In this way, when the distal end 4b of the grasping wire 4 returns to its memorized shape, the entirety thereof does not deform and recover at the same time, but when the restraint by the sheath 3 is released from the distal end side, the distal end 4b
It gradually deforms into a memorized shape from the open tip side. Therefore, the stone 28 is curved and surrounded along the surface of the stone 28 without causing unnecessary undulations during the process of recovering its shape.

That is, as the distal end portion 4b of the grasping wire 4 protrudes from the distal end of the sheath 3, it deforms while drawing an arc as small as possible, as shown by the dotted line in FIG. 6-a. Therefore, in this grasping operation, there is no wasted movement, the stone 28 is not popped and missed, and the wall surface of the bile duct 17 is not damaged due to unnecessary undulations, and the grasping action is performed reliably and safely.

In addition, as shown in Fig. 6-b, in the conventional method in which the entire gripping tip 4b of the gripping wire 4 protrudes from the tip of the sheath 3 in advance, it is difficult to recover from the straight state to the memorized shape. , since the memory processing part recovers its shape uniformly, it recovers while drawing a large arc as shown by the dotted line.

In other words, it shows a large unnecessary undulation. Therefore, the stone 28 can be easily removed and the wall surface of the bile duct 17 can be easily damaged.

7 and 8 show a second embodiment of the present invention. The wire 4 in this embodiment is not moved back and forth, but its distal end 4b always protrudes from the distal end of the sheath 3, and its proximal end is liquid-tightly attached to a cap 19 fixed to the operating section main body 7. It is fixed with adhesive. Note that the cap 19 is freely attached to the operation section main body 7 by screwing. A backing 20 is inserted between the operating section main body 7 and the cap 19.

As shown in FIG. 8, the shape memory portion of the wire 4, that is, the tip portion 4b protruding from the sheath 3, is coated with a plurality of resin coating layers 21, 22, 23, 24 in multiple layers to serve as a shape memory element for gripping. This constitutes a means for restraining the shape recovery operation of the wire 4 in stages. These resin coating layers 21, 22, 23, and 24 are made shorter on the distal end so that the thickness of the entire layer becomes thinner toward the distal end. It is formed in stages so that it becomes shorter on the sides.

Therefore, when this calculus remover 1 is introduced into the bile duct 17 to capture a calculus as described above, there is no need to move the wire 4 back and forth. That is, resin coating layer 2
1, 22, 23, and 24 in stages, the thickness of the coated layer becomes thinner toward the tip. Therefore, the shape recovery operation of the gripping wire 4 is sequentially deformed starting from the distal end side where the restraining force is smaller. Therefore, similarly to the above, when the distal end portion 4b of the grasping wire 4 returns to its memorized shape, the entirety does not deform and recover at the same time, but gradually deforms into the memorized shape from the distal end side.

, and in the process of recovering its shape, it curves and surrounds the stone 28 without causing any unnecessary undulations. That is, the tip 4b of the grasping wire 4 is connected to the sheath 3.
As it protrudes from the tip, it deforms while drawing an arc as small as possible, as shown in Figure 6-a. Therefore, in this grasping operation, there is no wasted movement, the stone 28 is not popped and missed, and the wall surface of the bile duct 17 is not damaged due to unnecessary undulations, and the grasping action is performed reliably and safely.

FIGS. 9 and 10 show a third embodiment of the present invention. In this embodiment, the distal end portion 4b of the gripping wire 4 is constructed in the same manner as in the first and second embodiments, but furthermore, the left and right wire portions of the wire 4 folded in half at the deformable distal end portion 4b are Thin wire rods 25, such as so-called tegus, are stretched at approximately equal intervals between 4c and 4c. In this embodiment, the distance between the left and right wire portions 4c, 4c is slightly larger than that of the above embodiment.

According to the configuration of this embodiment, the wire rod 25 and the left and right wire portions 4c, 4c form a bag shape, and when deformed as shown in FIG. be able to.

In addition, in this third embodiment, instead of stretching the wire rod 25, a net-like material may be stretched.

74511 and FIG. 12 show a fourth embodiment of the present invention. This embodiment has the same overall configuration as the first and second embodiments, or is different in the memorized shape of the tip 4b of the gripping wire 4. That is, the first
As shown in FIGS. 1 and 12, the inner loop 27a and the left and right outer loops 27b, 27b constitute multiple loops, and the diameter of the inner loop 27a is larger than the diameter of the outer loops 27b, 27b on the left and right outer sides. It is also formed small. Other configurations and methods of use are the same as those of the first and second embodiments.

Therefore, with the shape described above, the stone 18 taken in when the distal end portion 4b of the grasping wire 4 is heated and deformed into the memorized shape as shown in FIGS. 11 and 12 is difficult to fall off. Further, it can be used for stones 18 of different sizes.

Note that in this type of configuration, the number of loops is not limited to that of the above embodiment, and may be any number of loops. If the space for trapping stones is drum-shaped, similar effects can be achieved.

FIG. 13 shows a fifth embodiment of the present invention. In this embodiment, the shape stored in the tip end 4b of the gripping wire 4 is formed into a drum-like spiral as a whole, as shown in FIG. Further, the central axis direction of the helix is arranged to be perpendicular to the longitudinal direction of the sheath 3. The tip 4b of the gripping wire 4 is a straight line along the long direction of the sheath 3 before being transformed into a high temperature phase. Further, the leading end 4d of the gripping wire 4 is rounded into a spherical shape by melting or welding. If the distal end 4d is thus rounded into a spherical shape, the distal end will not damage the inner wall of the body cavity.

FIG. 14 shows a sixth embodiment of the present invention. In this embodiment, like the fifth embodiment, the shape stored in the tip 4b of the gripping wire 4 is formed into a drum-shaped spiral as a whole, as shown in FIG. , is different in that the helical center axis direction is made to coincide with the longitudinal direction of the sheath 3.

Note that the present invention is not limited to the above embodiments. For example, as a means for suppressing the shape memory A element from being deformed sequentially from the tip side, the shape memory alloy may be heat-treated so that the transformation temperature becomes lower toward the tip side, or the composition may be changed. Further, the shape memory element may have a tapered shape that becomes thinner toward the distal end, and in this case, the heat capacity becomes smaller toward the distal end, and deformation becomes faster.

Further, the heating means may be one that supplies hot water or may be one that uses electricity.

Furthermore, the application of the present invention is not limited to a stone removal tool, but also a thrombus removal tool 3 as shown in FIG.
1 or a blood vessel dilator 41 as shown in FIG. In the figure, 32.42 is a sheath, and this sheath 32,
Wires 34 and 44 protrude from the tip of 42. Also, 35.45 is a blood vessel.

In the case of the thrombus removal device 31, the wire 3 made of a shape memory alloy
A spiral shape is memorized at the tip of 4.

Further, in the case of the blood vessel dilator 41, a spiral shape is memorized at the tip of the wire 44 made of a shape memory alloy.

In the case of such a thrombus removal device 31 and a blood vessel dilator 41, the memorized shape must be more complicated than that of the stone removal device 1 of the above embodiment, but in such a case, the present invention is particularly suitable for the H effect. It is.

[Effects of the Invention] As explained above, the shape memory operating body of the present invention is provided with means for restricting the shape recovery operation of the shape memory element in stages, and the shape memory operation is suppressed in the process of recovering the memorized shape by the heating means. The body is restrained in stages, suppressing unnecessary undulating movements as much as possible. Therefore, especially in narrow cavities,
The treatment can be performed reliably without causing any damage to the surrounding area and by performing stable shape recovery operations.

4. Brief explanation of the drawings.

Fig. 1 is a side view of a stone remover showing the first embodiment;
The figure is a side sectional view of the operation part of the stone remover according to the first embodiment, FIG. 3 is a perspective view of the tip of the stone remover according to the first embodiment, and FIG. 4 is the same as the first embodiment. FIGS. 5A and 5B are side sectional views of the distal end portion of the example stone remover; FIGS.

Figures 5-c and 5-d are explanatory diagrams of the operation of the grasping wire in the stone remover of the first embodiment, respectively, and Figure 6-a is an explanatory diagram of the operation of the grasping wire in the stone remover of the first embodiment. Figure 6-b, an explanatory diagram of the principle operation of the gripping wire, is this first
FIG. 7 is an explanatory diagram of the principle operation of another system for comparison with the principle operation of the grasping wire in the stone remover according to the second embodiment of the present invention, and FIG. 7 is a side sectional view of the stone remover according to the second embodiment of the present invention. ,
FIG. 8 is an enlarged side sectional view of the vicinity of the tip of a stone remover according to the second embodiment, FIG. 9 is a plan view of the tip of a stone remover according to the third embodiment of the present invention, and FIG. 11 is a side view of the tip of a stone remover according to the fourth embodiment of the present invention, and FIG. 12 is a side view of the tip of a stone remover according to the fourth embodiment of the present invention. FIG. 13 is a side view of the distal end of the stone remover according to the fifth embodiment of the present invention, FIG. 14 is a perspective view of the distal end of the stone remover according to the fifth embodiment of the present invention, and FIG. 14 is a side view of the distal end of the stone remover according to the fifth embodiment of the present invention. FIG. 15 is a perspective view of an example of use of the thrombus remover, and FIG. 16 is a perspective view of an example of use of a blood vessel dilator.

DESCRIPTION OF SYMBOLS 1... Stone remover, 2... Operation part, 3... Sheath, 4... Grasping wire, 17... Bile duct, 18...
Stone, 31... thrombus removal device, 41...-vascular dilator,
32°42...Sheath, 34.44...Wire.

Applicant's agent Patent attorney Tsuboi 4 Figure 1 Figure 2 Figure 3 Figure 4 Figure 115-a Figure 5-b Figure 15-
Figure C Figure 5-d Figure 5-a
Figure 6-b' @ Figure 9 Figure 10 Figure 112

Claims (1)

[Claims] A shape memory operating body operated using a shape memory element that recovers a memorized shape by heating means, characterized in that the shape memory operating body is provided with means for restricting the shape recovery operation of the shape memory element in stages.