JPH0363043A - Laser probe - Google Patents

Abstract

PURPOSE:To prevent an optical fiber from breakage and a terminal face of inlet and outlet of a laser beam from burning by providing continuously a plurality of optical fibers consisting of different materials in the axial direction. CONSTITUTION:When a laser probe 1 is used by perforating it in a forceps channel of an endoscope, the min. carvature F is a part corresponding to a curved part of an apex part of the endoscope. In this case, the part corresponding to the curved part of the apex part is made of the 2nd optical fiber 3b of a flexible different material. Therefore, it is prevented from breakage in comparison with the 1st optical fiber 3a for guiding a middle and far IR laser light which is poor in flexibility. As the optical fiber main body 3 as a whole is prevented from breakage, it is possible to apply it to an endoscope and to radiate an onset part in a body cavity with an intermediate and far IR laser beam through an endoscope observation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laser probe that guides laser light emitted from a laser oscillator to an irradiated part.

[Prior Art] In the medical field, treatment is performed in which a laser probe is used to shine a laser beam onto a lesion such as a stone formed in a body cavity, and cauterize it to destroy and remove it. This involves connecting a laser probe with an inserted optical fiber facing the input optical system of a laser oscillator, pushing the laser probe through the forceps channel of the endoscope to the target site in the body cavity, and then The laser beam generated by the oscillator is focused by an input optical system onto the input end face of the optical fiber, and is then transmitted to the tip of the optical fiber, where it is emitted from the end face toward the lesion.

Currently, fluoride glass fibers, chalcogenide glass fibers, and the like are being developed as optical fibers for guiding laser light in the middle and far infrared regions.

An example of an optical fiber cable using such an optical fiber is the optical fiber cable disclosed in Japanese Patent Laid-Open No. 63-287804, which is a non-standard optical fiber cable that guides invisible laser light into a glass tube that guides visible laser light. A 1M optical fiber is pushed through to form an optical fiber cable, and visible and invisible laser beams are guided at the same time by guiding visible laser light through a glass tube, whereas invisible optical fibers cannot guide visible laser light. However, the operator can confirm the irradiation position of the invisible laser beam using the visible laser beam.

In addition, in the optical fiber device for power transmission disclosed in Japanese Patent Application Laid-Open No. 63-273805, two fibers with a hole-thickness are provided consecutively in the axial direction, making it easy to replace the optical fibers. This can be done in one operation, making the replacement work easier and reducing the replacement time.

[Problems to be Solved by the Invention] Among the above-mentioned problems, optical fibers for guiding far-infrared laser light generally have poor flexibility, and it is difficult to insert the optical fiber into a forceps channel of an endoscope to remove its curved portion. If the optical fiber is bent to a small radius, there is a problem that the optical fiber may break. Further, the melting point of the fluoride fiber is low, and when the laser beam is input to and output from the dirt on the end face of the fiber, the input/output end face is likely to be burnt out. Furthermore, the optical fiber device for power transmission disclosed in JP-A No. 63-273805 does not have any technical concept of providing optical fibers made of different materials, but simply has a structure in which end fibers of different thicknesses are provided, and the above-mentioned problems occur. Inevitable.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to prevent breakage of optical fibers and burnout of laser beam input/output end faces, expand the range of application, and improve durability. The object of the present invention is to provide a laser probe that can be used for various purposes.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a laser probe that guides laser light emitted from a laser oscillator to an irradiated part via an optical fiber, in which a plurality of light beams made of different materials are used. The fibers are provided continuously in the axial direction.

[Operation] In such a configuration, the laser beam generated by the laser oscillator is focused by the input optical system on the input end face of the optical fiber, is incident thereon, and is transmitted through several types of optical fibers to the tip. , and irradiates the irradiated portion from its output end face. By using optical fibers with excellent flexibility and heat resistance, even if the transmittance of laser light is slightly sacrificed, for parts of the optical fiber that require small bending radius or high heat resistance, This prevents the end fiber as a whole from being broken or burned out.

[Example] Hereinafter, an example of the present invention will be described with reference to FIG.

In the figure, 1 is a laser probe, which is formed by inserting an optical fiber body 3 into a flexible sheath body 2. The sheath body 2 is divided into two parts, a first sheath 2a and a second sheath 2b.
A positioning chip 4 connects both ends of each sheath 2a to
Connected by fitting into s 2 b 1. Further, a distal tip 5 connects one end of the second sheath 2b to the distal end of the second sheath 2b.
It is fitted and installed inside. Further, the rear end of the first sheath 2a is inserted into and connected to the west of the center hole 8 at the bottom of the connector 7 in the shape of a cylinder with a bottom in the laser oscillator 6.

The optical fiber main body 3 is also divided into two parts, a first optical fiber 3a and a second optical fiber 3b, and one end of the first optical fiber 3a is provided in the connector 7 of the laser oscillator 6. Center hole 1 of fiber holder 9
0 and the other end is fixed to the first sheath 2a.
It is fixed by being pushed through the inside of the positioning chip 4. - On the other hand, one end of the second optical fiber 3b is similarly pushed through and fixed to the west of the positioning tip 4, and the other end is pushed through and fixed into the tip tip 5 provided at the tip of the second sheath 2b.
Fixed. That is, the first optical fiber 3a and the second optical fiber 3b are disposed continuously in the axial direction within the positioning chip 4 with their end faces facing each other. It should be noted that each end face of the first and second optical fibers 3a and 3b exposes the core portion within the cladding to improve the laser beam input and output characteristics.

Further, a threaded portion 11 is provided on a part of the outer periphery of the fiber holder 9 that holds one end of the first optical fiber 3a, and this threaded portion 11 is attached to a positioning ring 12 provided on the outside of the fiber holder 9. It is threadedly engaged with the threaded portion 13. Further, a plurality of screws 14 are screwed through the outer peripheral portion of the positioning ring 12 at right angles thereto, and the fiber holder 9 is positioned and fixed in the axial direction with respect to the positioning ring 12 by screwing in the screws 14. Furthermore, a plurality of screws 15 are screwed through the outer circumference of the connector 7 that holds the rear end of the sheath body 2 at right angles thereto, and the tips of the screws 15 are recessed in the outer circumference of the positioning ring 12. It is pressed against the screw receiving part 16 which has been rotated. Then, by screwing in the screw 15, the positioning ring 12 is pressed toward the stepped portion 17 protruding inside the connector 7, whereby the positioning ring 12 is pressed against the connector 7.
Two axial and radial ridge positions are fixed.

Then, the first optical fiber 3a of the optical fiber main body 3
An optical fiber for guiding medium to far-infrared laser light, such as a fluoride glass fiber, is used as the second optical fiber 3b, and an optical fiber made of a material different from that of the first optical fiber 3a is used as the second optical fiber 3b. . Here, the second optical fiber 3b is inside.

Although the far-infrared laser beam transmittance is inferior to that of the first optical fiber 3a, the replaceability is superior to that of the first optical fiber 3a.

In such a configuration, an input optical system (not shown) is disposed opposite the rear end surface of the first optical fiber 3a, that is, the input end surface 18 of the laser beam, but the attachment of the input end surface 18 to this input optical system is The position is the above positioning ring 12
Further, screws 14 and 15 screwed onto the connector 7 are used to adjust and fix the laser beam to the condensing position. Then, the laser probe 1 is inserted into a forceps channel of an endoscope (not shown) and inserted into the body cavity, and the output end surface 19 of the first optical fiber 3a is placed opposite to the lesion using the observation device of the endoscope. do. When the laser oscillator 6 is operated in this state, a laser light source (not shown) generates a laser beam, and this laser beam is focused by the input optical system on the input end face 18 of the first optical fiber 3a and is incident thereon. The light is further transmitted from the first optical fiber 3a to the second optical fiber 3b, and is irradiated from its output end face 19 toward the lesion.

Here, when the laser probe 1 is used by being inserted into a forceps channel of an endoscope, the bending R is minimized at a portion corresponding to the curved portion at the tip of the endoscope. At this time,
If the entire optical fiber is an optical fiber suitable for guiding mid- to far-infrared laser light, this optical fiber has poor flexibility, so there is a problem that the part corresponding to the above-mentioned curved part at the tip breaks. .

However, although the first optical fiber 3a for guiding medium to far-infrared laser light is used over almost the entire length of the laser probe 1, the part corresponding to the curved part at the tip is more flexible. A second optical fiber 3 with a rich sealant
Medium because I used b.

Breakage of the first optical fiber 3a for guiding far-infrared laser light, which has poor flexibility, can be prevented. In this way, the optical fiber main body 3 as a whole can be prevented from breaking.
It becomes possible to apply it to an endoscope, and it becomes possible to irradiate a lesion in a body cavity with mid- to far-infrared laser light in a trans-internal NvL manner.

Normally, the medical laser probe 1 has a total length of about 4 m.
On the other hand, the part that requires a small bending radius is the tip 1.
It is about 0 cm. In other words, the length of the second optical fiber 3b only needs to be 10 cm or more, which is short compared to the entire length of the optical fiber main body 3, even if it sacrifices the transmittance of mid- and far-infrared laser light. It's at a level that doesn't cause any problems.

2 and 3 show other embodiments of the invention.

This embodiment is the same as the optical fiber main body 3 in the above embodiment.
is divided into three parts from first to third optical fibers 3a to 3c, and the first optical fiber 3 serves as the third optical fiber 3C.
An optical fiber ribbon made of a different material from a is used. Here, the melting point of the fused glass, which is the material of the first optical fiber 3a for guiding medium and far-infrared laser light, is about 500°C, and the melting point of the material of the second and third optical fibers 3 b s 3 c is about 500°C. The melting point of quartz glass, which is considered to be one, is about 2000°C,
Although the third optical fiber 3 b s 3 c is inferior to the first optical fiber 3 a in transmittance of medium to far infrared laser light, it is superior in heat resistance to the first fiber 3 a.

Further, the rear end of the first fiber 3a is attached to a fiber holder 9.
The third optical fiber 3C is inserted into and fixed in the first center hole 10a of the fiber holder 9, and the third optical fiber 3C is inserted into the second center hole 10b of the fiber holder 9.
It is inserted inside and fixed. That is, the first optical fiber 3a and the third optical fiber 3C are disposed continuously in the axial direction within the fiber holder 9 with their end faces facing each other. Note that the other basic configurations are the same as those of the first embodiment.

If the laser beam is directly focused as it is, it will be as shown in Figure 3 (a).
It shows a power distribution characteristic as shown below, with power concentrated on the optical axis (center), where the power density is highest, and becomes extremely low toward the outside. On the other hand, when the laser beam passes through the end fiber, it is reflected and transmitted through the optical fiber west, and as shown in FIG. 3(b), the peak on the optical axis decreases, and the difference in power density of the entire beam decreases.

Therefore, as in this embodiment, the laser beam focused by the input optical system 91 is transmitted through the third end fiber 3C, which has better heat resistance, and then enters the first optical fiber 3a. By doing so, it is possible to prevent the incident end surface 18 of the first optical fiber 3a, which is used for guiding medium and far infrared laser light and has a low melting point, from being burnt out.

Furthermore, since the second optical fiber 3b with excellent heat resistance is provided on the tip side of the first optical fiber 3a, if dirt such as bodily fluids or cautery pieces adheres to the laser beam emission end face 19, this emission end face Even if the laser beam is emitted from the laser beam 19, it is possible to prevent the emission end face 19 from being burnt out due to heating caused by the emission loss.

Here, the portion of the optical fiber main body 3 that requires high heat resistance is about 1 cm from the input and output ends, that is, the lengths of the second and third optical fibers 3b and 3c only need to be 1 cO1 or more, and the optical fiber Overall length of main body 3 (about 4m)
This is short and medium compared to .

This is at a level where there is no problem even if the transmittance of far-infrared laser light is sacrificed.

Note that the present invention is not limited to the above embodiments. For example, in the second embodiment, second and third optical fibers 3b and 3c made of different materials from the main optical fiber 3a are arranged on the side facing the image end of the optical fiber main body 3; The optical fiber 3a and the optical fiber made of optical material may be arranged only on the input end side. Also,
The second optical fiber 3b and the third optical fiber 3c do not need to be made of the same material; the second optical fiber 3b may be made of a highly flexible material, and the third optical fiber 3c may be made of a material with excellent heat resistance. You can choose the material that is suitable for each required function. Furthermore, it is also conceivable to arrange another optical fiber between each of the first to third fibers 3a to 3c, if necessary.

[Effects of the Invention] As described above, according to the present invention, by arranging optical fibers made of the most suitable material for each part of an optical fiber with different required characteristics, breakage of the optical fiber and laser radiation can be prevented. It is possible to prevent burnout of the end face of the predecessor mountain village, expand the range of application, and improve durability.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of the main part showing one embodiment of the present invention, Figs. 2 and 3 show other embodiments of the invention, Fig. 2 is a cross-sectional view of the main part, and Fig. 3 ( (a) and (b) are characteristic diagrams of laser light, respectively. 1... Laser probe, 3... Optical fiber body, 3
a... First optical fiber, 3b... Second optical fiber, 3C... Third optical fiber 6... Laser oscillator.

Claims (1)

[Claims] A laser probe that guides laser light emitted from a laser oscillator to an irradiated part via an optical fiber, characterized in that a plurality of optical fibers made of different materials are continuously provided in the axial direction.