JPS5846923A - Endoscope - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an endoscope and an endoscope equipped with operating tools such as forceps and treatment tools.

Viewing the inside of a living body's cavities or internal organs using an endoscope! In the treatment of body cavities and internal organs, tissue is removed or treated by inserting forceps or treatment instruments through the forceps holes that pass through the endoscope. These forceps and instruments include biopsy forceps,
Basket forceps, high-frequency snares, three-pronged forceps, alligator forceps, coagulators, cleaning tubes, detailed examination brushes, etc. 6
There are various shapes, but each requires a specific shape and size t for its purpose of use. Note that these forceps and treatment tools will be collectively referred to as "manipulation tools" hereinafter. However, on the other hand, in order to minimize the insertion resistance and pain experienced by the patient when inserting the endoscope into the body cavity of a patient, the outer diameter of the head and connecting portion of the endoscope is made as small as possible. Therefore, it is desirable that the diameter of the forceps hole through which the operating tool is inserted and guided into the body cavity be small.

Conventional endoscopes equipped with operating tools have been unable to simultaneously satisfy these contradictory requirements, and have been forced to make some compromises. For example, basket forceps are inserted into a forceps hole after being deformed within the elastic limit of the material, so the resistance during insertion is large. In addition, in side-viewing endoscopes, in order to enable these operating tools to be used while standing upright in a direction approximately perpendicular to the longitudinal direction of the endoscope, a forceps stand that is operated by a wire from the operating section is installed. Prepared for its head.

Providing such a movable part in the head of the endoscope increases the size of the head and the connecting part, and reduces the reliability of the device due to mechanical movement.The present invention overcomes these drawbacks of the prior art. The aim is to solve this problem and provide an endoscope that causes less pain to the patient during insertion.

Another object of the present invention is to provide a highly reliable endoscope that has a necessary shape and size in use, and can be inserted and removed without any resistance.

According to the invention, these objectives are achieved by an endoscope as follows. In other words, within this.

The viewing device includes a guide path that guides the operating tool inserted from one end to the other end, and a heating means provided near the other end of the guide path to heat the operating tool, and this operating tool is not in use. 1st suitable for
The heating means is configured to heat the operating tool that has been deformed into a second shape different from the first shape to a temperature higher than the reverse transformation temperature of the shape memory alloy to transform the operating tool into the first shape. It restores the shape.

The shape memory alloy of the operating tool may have a reverse transformation temperature substantially equal to the body temperature of the living body using the operating tool, and the heating means may heat the operating tool above the body temperature.

The conduit guiding the operating tool may be provided with cooling means for keeping the operating tool inserted therein below the reverse transformation temperature of the shape memory alloy.

Next, embodiments of the endoscope according to the present invention will be described in detail with reference to the accompanying drawings. Note that in this specification, the term "endoscope" includes not only endoscopes used in living bodies, but also industrial endoscopes used in internal cavities of devices and the like.

FIG. 1 is a partially cutaway side view of an endoscope according to the present invention, showing the portion of the endoscope that is inserted into the main cavity, that is, the head. This head has a cylindrical sheath 10t made of plastic or metal coated with plastic, through which an operating tool 12, such as forceps such as the illustrated basket forceps or a treatment tool, is passed through the end. A forceps hole 14 for performing suction is provided. Forceps hole 14
is connected to a 1 ft tubular conduit that guides the operating tool 12, and the sheath 1
A heating means 18 is provided at the connection between the forceps hole 14 and the guide path 16 so as to surround the guide path 16.

The heating means 18 is a resistance heating element made of a wire-wound resistor, a carbon solid resistor, etc. that surrounds the tubular guide path 16, and is connected to an external power source (not shown) via a lead wire 20''a'. Connected.

In addition, the sheath 10 is provided with mechanisms necessary for an endoscope, such as an objective lens 22 and an image bundle 24 made of optical fibers, and other mechanisms such as a light guide and air/water pipes are provided. The illustration is omitted to avoid complication of the figure.

As is well known, the basket forceps 12 are used to capture, for example, a knot in a body cavity and take it out of the body, and when in use, it takes the shape as shown in the figures. According to the invention, the basket forceps 12 are made of a so-called "shape memory alloy".

"Shape memory alloy" is a well-known alloy that extinguishes the strain caused by plastic deformation when heated above a certain temperature (reverse transformation temperature). More specifically, a shape memory alloy formed into a certain shape is heated above the transformation temperature to form a high-temperature phase crystal structure called the beta phase or matrix phase, and then rapidly cooled below the transformation temperature to form malten. In this state, stress is applied to the alloy to deform it into a shape different from its original shape.The strain caused by this deformation is retained, but there is no point in heating it above the reverse transformation temperature. This distortion disappears and the original shape is restored.This is said to be due to the reverse transformation of the martensite structure to the parent phase.

Operation tool 12 such as basket forceps for an endoscope according to the present invention
is made of this shape memory alloy.

For example, the basket forceps 12 shown in FIG. 1 is formed into the shape shown in FIG. 1, and is heated above the transformation temperature and then rapidly cooled. The forceps 12 are inserted into the tubular channel 16 from the forceps insertion hole (not shown) in the operating section of the endoscope, and are temporarily deformed into a long shape into the forceps hole 14 in the head. It is desirable to insert it into the conduit 16. The basket forceps 12 thus deformed is heated to a temperature higher than the reverse transformation temperature of the shape memory alloy by energizing the heating means 18 provided near the forceps hole 14, and the basket forceps 1 is returned to its original shape, that is, in its used state.
Restore to the shape of 2.

The operating tool 12 is Ti-Ni, Ag-Cd.

Au-Cd, Cu-Al-Ni, Cu-Al-Zn
.

Shape memory alloys such as Cu-Zn and Ni-Al are used, although Ti-Ni and Cu-At-Zn are suitable.

In the case of an endoscope to be inserted into a body cavity of a living body, it is desirable to appropriately select the composition of the shape memory alloy of the operating tool 12 and set its reverse transformation temperature near the body temperature of the living body. There is a possibility that the response time for the operating tool 12 to restore its original shape due to natural heating due to body temperature will be longer, and the heating means 1
It is desirable to use 8. By using the heating means 18, it is possible to set a high reverse transformation temperature for restoring the shape of the operating tool 12 to its original shape.
The range of selection of the composition of the shape memory alloy, that is, the degree of freedom is increased. However, in the case of an endoscope used on a living body, it is undesirable to cause damage or pain to the living body due to the temperature increase caused by the heating means, so it is effective from the above points to heat the endoscope to a temperature slightly higher than the body temperature of the living body. . - 74% Cu, for example in the case of Cu-AL-Zn.

With a composition of 8% At and 18% Zn, the martensitic transformation start temperature can be set at 38°C. Therefore, according to the present invention, it is generally desirable to set the temperature so that reverse transformation occurs at a temperature slightly higher than normal temperature that does not cause damage or pain to living organisms, that is, 30 to 50°C. If the reverse transformation temperature is low, cool the operating tool 12 in advance and immediately insert it into the forceps insertion hole (
(not shown) into the tubular conduit 16. Tubular conduit 16
The endoscope may be configured so that the operating tool 12 is kept below the reverse transformation temperature of its shape memory alloy by cooling the operating tool 12 with a water pipe or the like.

Since such shape memory alloys also have so-called "pseudo-elastic" or "super-elastic" properties, the endoscope according to the present invention allows the operating tool 12\1-tubular conduit 16 to return to its original shape after insertion. It is also advantageous when pulling out in the original direction through the holder.

"Pseudoelasticity" or "superelasticity" means that even if the normal elastic limit is reached and stress is applied, distortion will occur as if it had undergone plastic deformation, but when the stress is removed, it will return to its original shape.
Refers to the property of not leaving any permanent distortion. Therefore, in the endoscope shown in FIG. 1, the basket forceps 12 made of such a shape memory alloy return to a usable shape, capture a stone in the body cavity, and then pass through the guide channel 16 in the opposite direction to the insertion. It is smoothly taken out from the forceps insertion hole (not shown) of the endoscope operating section by following the direction t. Such an operating tool 12 can withstand repeated use many times and has a long life.

As such an operating tool 12, in addition to the sket forceps, there are forceps for scraping out stones having shapes as shown in FIGS. 3(A), 3(B), and 3(C). It is made of a shape memory alloy such as Ti-Ni, and remembers the shape shown in the figure when in use, and when inserted into an endoscope, it is deformed into a planar shape as shown in Fig. 4.As a result, it quickly It can be smoothly inserted into the guide path 16, heated by the heating means 18 in the vicinity of the opening 14, and restored to its original shape, that is, the shape shown in FIG. 3, and ready for use.

Another embodiment of the endoscope according to the present invention is shown in FIG. This is an example of a side-viewing endoscope, unlike the direct-viewing endoscope shown in FIG. 1, and the same components as shown in FIG. 1 are designated by the same reference numerals.

The head of this endoscope is divided into two chambers by a partition 30. The right side of the partition 30 in the figure is completely waterproof, and the operation tool 32 such as the biopsy forceps shown as an example can be used with a conductive mirror or prism 34 and an imaging lens 36.
, as well as an image node (y doshi 24) consisting of optical fibers.
is accommodated. In addition, a lower light guide 3B is shown as an example of a mechanism necessary for an endoscope, and this extends through 30 partitions to the upper window 40 of the left chamber as shown in the figure. The left end of 16 forms an opening 4'2 in the partition 30 and is provided with heating means 18 as shown.This may be the same as the embodiment shown in FIG. In other words, an opening 44 is formed in the upper part of FIG. 5, and this has a rectangular shape long in the longitudinal direction of the endoscope when viewed from the upper part of the figure.Other mechanisms necessary for the endoscope are as follows. The illustration is omitted to avoid complicating the figure.

In use, a self-erecting forceps or instrument 32, such as a cannulation tube or biopsy forceps as shown, is bent upwardly through the opening 42 at the left end of the tubular conduit 16 and extends through the rectangular opening. Go outside from 44.

The neck 46 of the biopsy forceps 32 shown as an example is made of a coiled shape memory alloy or a straight or tubular shape memory alloy as shown in the figure, and stores the shape of the used state as shown in the figure. . 'f That is, it is formed into the shape shown in the figure, heated above the transformation temperature, and rapidly cooled.

If necessary, it is cooled to make it straight as in the case shown in FIG. 4, inserted into the tubular conduit 16 through the forceps insertion hole of the endoscope operating section, and heated to a temperature higher than the reverse transformation temperature by the heating means 18. The embodiment shown in FIG. 5 then returns to its original shape as shown in the figure and becomes ready for use. In the embodiment shown in FIG. Since there is no need for mechanisms such as wires to operate the endoscope, the size of the endoscope itself is reduced, and the number of mechanically moving parts is reduced, which improves the reliability of the device.

By configuring the endoscope according to the present invention as described above, it is possible to smoothly take in and out an operating tool having a necessary shape and large width when in use. Therefore, the diameter of the endoscope can be made thinner relative to the required shape and size of the operating tool, thereby reducing the pain caused to the patient. Furthermore, even when a self-erecting operating tool is used in a side-viewing endoscope, the reliability of the device is improved because the number of mechanically movable parts can be reduced.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional side view showing an embodiment of the endoscope according to the present invention; FIGS. 2, 3, and 4 are views showing the shape of the operating tool used in the endoscope according to the present invention; The figure is a partial sectional view showing another embodiment of the endoscope according to the present invention. Explanation of main symbols 12... Operating tool, 16... Tubular conduit 18...
Heating means, Patent applicant Fuji Photo Film Co., Ltd. Fuji Photo Kohki Co., Ltd. Figure 1 4 Figure 5 Figure 3 (A) (B) (C) Figure 4 Figure 2

Claims (1)

[Claims] 1. Guides an operating tool inserted from one end to the other end (including a guide path and a heating means provided near the other end of the guide path for heating the operating tool, the operating tool The heating means includes a shape memory alloy that memorizes a first shape suitable for a usage condition, and the heating means heats the operating tool transformed into a second shape different from the first shape to a temperature higher than the reverse transformation temperature of the shape memory alloy. 2. The endoscope according to claim 1, wherein the shape memory alloy has a reverse transformation temperature higher than that of the operating tool. 1 to use
5. An endoscope, wherein the temperature is substantially equal to the body temperature, and the heating means heats the operating tool to a temperature higher than the body temperature. 3. 9. In the endoscope according to claim 1, the guide path includes cooling means for keeping the operating tool inserted into the guide path at a temperature equal to or lower than the reverse transformation temperature of the shape memory alloy of the operating tool. An endoscope comprising: