JP6463218B2 - Laser therapy apparatus and photodynamic therapy apparatus for esophageal cancer - Google Patents

Description

  The present application relates to a laser therapy apparatus. In particular, the present application relates to a laser treatment apparatus for an endoscope.

  In the medical field, a light irradiator that irradiates light to a desired part of a patient or a subject is used for treatment or examination. In recent years, photodynamic therapy (hereinafter abbreviated as “PDT”) has attracted attention. PDT is a local treatment method using a photochemical reaction caused by light irradiation to a photosensitive substance. For example, a photosensitive substance that accumulates in a large amount in cancer cells is used, and the cancer cells are selectively destroyed by irradiating the affected area with laser light.

  Patent Documents 1 to 3 disclose the structure of the tip of a probe used for light irradiation. Patent document 1 is disclosing the optical fiber probe provided with a hemispherical glass lens. Patent document 2 is disclosing the optical fiber laser light guide probe which has the front-end | tip tip formed from nylon. Patent Document 3 discloses an optical fiber laser device in which a spherical lens is fixed to the tip of an optical fiber using a base.

Japanese Patent No. 2943094 JP-A-9-47518 Japanese Utility Model Publication No. 6-8910

  Provided is a laser treatment apparatus for an endoscope.

  A light irradiator according to a non-limiting exemplary embodiment of the present disclosure is a laser treatment apparatus for an endoscope, comprising: an optical fiber; a laser light generator connected to one end of the optical fiber; A cap formed of phenylsulfone, the cap having a hole portion for receiving the other end of the optical fiber, and a convex lens portion disposed along a direction in which the hole portion extends; And an adhesive material bonded to the other end.

  According to the present disclosure, a laser treatment apparatus for an endoscope is provided.

FIG. 1 is a perspective view illustrating an example of a laser treatment apparatus according to an embodiment of the present disclosure. FIG. 2 is a schematic diagram illustrating an example of an endoscope system. FIG. 3 is an enlarged view of the distal end portion 510 a of the insertion tube 510. FIG. 4 is an enlarged view of the tip of the probe 10. FIG. 5 is a diagram illustrating an example of a beam profile in the laser treatment apparatus 100. FIG. 6 is an enlarged view of the vicinity of the top of the convex lens portion 32. FIG. 7 is a graph showing the relationship between the distance d from the end face of the optical fiber 2 to the top 32t of the convex lens portion 32 and the energy density of the laser light at the position of the top 32t. FIG. 8 is a graph showing an example of changes in the output of laser light when blood is wiped after the blood is applied to the surface of the convex lens portion 32. FIG. 9 is a graph showing an example of a change in the output of laser light when blood is wiped after blood is applied to the surface of the GRIN lens in a conventional configuration having a GRIN lens. FIG. 10 shows an example of a probe in a laser therapy apparatus according to another embodiment of the present disclosure. FIG. 11 is a top view showing an example of the appearance of the tip of the probe 10A. FIG. 12 is a side view showing an example of the appearance of the tip of the probe 10A.

  First, an overview of one aspect of the present disclosure will be described.

[Item 1]
A laser treatment apparatus for an endoscope, which is an optical fiber, a laser light generator connected to one end of the optical fiber, and a cap formed from polyphenylsulfone, and receives the other end of the optical fiber A laser treatment apparatus comprising: a cap having a hole, and a convex lens disposed along the direction in which the hole extends; and an adhesive that couples the cap to the other end of the optical fiber.

  According to the configuration of item 1, a laser treatment apparatus for an endoscope is provided.

[Item 2]
Item 2. The laser treatment device according to Item 1, wherein an area of a portion of the surface of the convex lens portion from which the laser beam generated by the laser beam generator is emitted is larger than the diameter of the core of the optical fiber.

  According to the configuration of item 2, it is possible to suppress a decrease in output even when a body fluid (typically blood) adheres to the convex lens portion.

[Item 3]
When the distance from the other end of the optical fiber to the top of the convex lens portion is d and the numerical aperture of the optical fiber is NA, the relationship of 1.2 mm <d <2.4 mm and 0.2 <NA <0.3 is satisfied. Item 3. The laser treatment device according to item 1 or 2.

  According to the configuration of item 3, a relatively small probe can be realized.

[Item 4]
4. The laser treatment apparatus according to any one of items 1 to 3, wherein the convex lens part has an aspherical shape.

  According to the configuration of item 4, the top hat beam can be formed relatively easily.

[Item 5]
The laser treatment apparatus according to any one of items 1 to 4, wherein the beam emitted through the convex lens portion of the cap is a top hat beam.

[Item 6]
6. The laser treatment apparatus according to any one of items 1 to 5, wherein the cap has a second hole that reaches a side surface of the optical fiber.

  According to the configuration of item 6, the optical fiber and the cap can be more strongly coupled.

[Item 7]
The optical fiber has a jacket that covers at least a part of the side surface of the optical fiber, and the other end of the optical fiber is an exposed portion that is not covered by the jacket. Item 7. The laser treatment device according to any one of Items 1 to 6, wherein the laser treatment device has a space surrounded by a side surface and a jacket, and the space is filled with an adhesive.

  According to the configuration of item 7, the optical fiber and the cap can be coupled more strongly.

[Item 8]
A photodynamic therapeutic device for esophagus comprising the laser therapeutic device according to any one of items 1 to 7.

  Hereinafter, an embodiment showing an example of a laser treatment apparatus of the present disclosure will be described in detail with reference to the drawings. The drawings schematically show the size and shape of each part, and the actual size and shape of each part do not necessarily match those in the drawing. In the following description, components having substantially the same function are denoted by common reference numerals, and description thereof may be omitted.

(First embodiment)
FIG. 1 illustrates an example of a laser therapy apparatus according to an embodiment of the present disclosure. A laser treatment apparatus 100 illustrated in FIG. 1 includes a laser light generator 20 that emits laser light, and a probe 10 that irradiates an irradiation target with the laser light generated by the laser light generator 20. The probe 10 includes an optical fiber 2 and a cap 30 attached to the tip of the optical fiber 2. The cap 30 has a convex lens portion 32. In the configuration illustrated in FIG. 1, the end of the optical fiber 2 to which the cap 30 is not attached is connected to the laser light generator 20. Laser light generated by the laser light generator 20 is emitted from the convex lens portion 32 of the cap 30 through the optical fiber 2.

  As the optical fiber 2, various optical fibers suitable for guiding the laser beam can be used. For example, the optical fiber 2 may be a single mode or multimode optical fiber, a graded index polymer optical fiber (GI / POF), a bundle fiber, or the like. There is no restriction | limiting in particular in the diameter of the core of the optical fiber 2, For example, it is about 400 micrometers. The optical fiber 2 may be of a type that can be sterilized by gamma rays.

  The laser therapy apparatus 100 can be used for PDT, for example. That is, the laser light generator 20 may be a device that generates laser light having a wavelength suitable for treatment by PDT (for example, a wavelength of 664 nm ± 2 nm). Hereinafter, an example in which the laser treatment device 100 is a photodynamic treatment device for esophageal cancer treatment will be described.

  At the time of laser beam irradiation using the laser treatment apparatus 100, the tip of the probe 10 (the end on which the cap 30 is attached) is directed to the irradiation target (in this case, the affected part or examination target site in the esophagus). Typically, the tip of the probe 10 is directed to an irradiation target in a state where the probe 10 is disposed in a channel for biopsy (or suction) of an endoscope. The laser treatment apparatus 100 can be a laser treatment apparatus for an endoscope.

  FIG. 2 shows an example of an endoscope system having an endoscope. An endoscope system 500 illustrated in FIG. 2 includes an endoscope 505, a processing device 550, and a display 560. In the illustrated example, the processing device 550 includes a light source 340. The light source 340 is, for example, a xenon lamp. A display 560 is connected to the processing device 550. The endoscope 505 includes an operation unit 520, an insertion tube 510 that can be bent and connected to the operation unit 520, and a cable 530 that connects the operation unit 520 to the processing device 550.

  As will be described later with reference to FIG. 3, the distal portion 510 a of the insertion tube 510 generally includes an illuminator for illuminating the affected area (or examination target site), and an imaging unit for imaging the affected area. Is placed. For example, the illuminator emits light generated by the light source 340 of the processing device 550 toward the affected area. The imaging unit acquires an image (typically a moving image) of the affected part. The image acquired by the imaging unit is displayed on the display 560 via the processing device 550. That is, the cable 530 may have a light guide for guiding the light generated by the light source 340 to the illuminator, and a signal line for transmitting an electrical signal output from the imaging unit to the processing device 550.

  The operation unit 520 includes an angle change knob for changing the direction of the distal end portion 510a, a button for switching illumination on and off, and the like. A practitioner such as a doctor operates the endoscope 505 while holding the operation unit 520. The operation unit 520 includes a biopsy port (also referred to as a forceps insertion port) 517a. The biopsy port 517a communicates with a biopsy (or aspiration) channel (not shown) provided in the insertion tube 510. By inserting the distal end of the probe 10 into the channel from the biopsy port 517a, the distal end of the probe 10 can be disposed on the distal end portion 510a of the insertion tube 510.

  FIG. 3 shows the distal end portion 510a of the insertion tube 510 in an enlarged manner. In the configuration illustrated in FIG. 3, an imaging unit 511, two illuminators 512, and an opening 514 communicating with the biopsy channel 517 are provided on the end surface of the distal end portion 510 a. The imaging unit 511 can include an imaging element such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) sensor and an objective lens. The illuminator 512 may include an illumination lens. As shown in FIG. 3, a nozzle 513 may be further provided on the end surface of the tip portion 510a. The nozzle 513 discharges water for cleaning the objective lens of the imaging unit 511 and the illumination lens of the illuminator 512, for example.

  When the laser treatment apparatus 100 is used, the probe 10 is inserted into the biopsy channel 517 via the biopsy port 517a. At the time of laser beam irradiation using the laser treatment apparatus 100, the distal end of the probe 10 is positioned at the distal end portion 510a of the insertion tube 510 as shown in FIG. When the practitioner changes the direction of the distal end portion 510 a of the insertion tube 510 using the operation unit 520, the optical fiber 2 disposed in the biopsy channel 517 is bent according to the insertion tube 510. Thus, the practitioner can point the tip of the probe 10 in a desired direction by operating the operation unit 520. That is, the practitioner can point the convex lens portion 32 of the cap 30 attached to the optical fiber 2 toward the irradiation target site.

  Hereinafter, a configuration example of the probe 10 will be described in detail with reference to FIGS. 4 to 9.

  FIG. 4 shows the tip of the probe 10 in an enlarged manner. FIG. 4 shows an example of the external appearance of a part of the cap 30 and the optical fiber 2 when viewed from the direction perpendicular to the axis of the optical fiber 2.

  In the configuration illustrated in FIG. 4, the cap 30 has a generally cylindrical shape. A hole 34 is formed in one cylindrical end 30 a of the cap 30. The hole 34 extends along a cylindrical axis. The cylindrical shaft is typically linear. The hole 34 does not penetrate the cap 30. The cap 30 is fixed to the optical fiber 2 by the adhesive 40 in a state where the tip of the optical fiber 2 is inserted into the hole 34. In a state where the cap 30 is coupled to the optical fiber 2, the cylindrical axis of the cap 30 and the axis of the optical fiber 2 substantially coincide with each other.

  The adhesive 40 is filled in a space formed between the outer surface of the optical fiber 2 and the inner surface of the hole 34 of the cap 30. As the adhesive 40, for example, an epoxy resin adhesive, an acrylic resin adhesive, or the like can be used. Typically, the end face of the optical fiber 2 is in close contact with the bottom of the hole 34 (the part where the end face of the optical fiber 2 inserted into the hole 34 faces).

  The material constituting the cap 30 may be at least transparent to the light emitted from the optical fiber 2. The transmittance for light emitted from the optical fiber 2 is, for example, 80% or more. Examples of the material constituting the cap 30 are polyphenylsulfone, polyamide (for example, nylon), polyethylene, polyolefin, polystyrene, acrylic resin, and epoxy resin. Here, polyphenylsulfone is used as a material constituting the cap 30. Since polyphenylsulfone is a biocompatible material and can be gamma-ray sterilized, it is beneficial to construct the cap 30 from polyphenylsulfone.

  Hereinafter, a typical example of the shape of the cap 30 will be described in detail.

  The shape of the cap 30 is typically symmetric with respect to the axis of the optical fiber 2. That is, the cap 30 can be generally cylindrical. However, the cylindrical ends of the cap 30 do not have to be flat. Here, the one end 30a of the cylindrical shape of the cap 30 is a plane, whereas the surface of the end 30b facing the end 30a is a convex curved surface. Since the surface of the end portion 30b has a convex curved surface shape, the convex lens portion 32 is formed on the cap 30. The convex lens portion 32 is disposed along the direction in which the hole portion 34 extends.

  The shape of the convex lens portion 32 when viewed along the direction in which the hole 34 extends typically has rotational symmetry. The rotationally symmetric axis in the convex lens portion 32 substantially coincides with the axis of the optical fiber 2. The convex lens portion 32 may have an aspheric shape. When the convex lens portion 32 has an aspherical shape, it is advantageous because a beam profile of a top hat can be obtained relatively easily. In the embodiment of the present disclosure, the beam emitted through the convex lens portion 32 of the cap 30 is a top hat beam.

  FIG. 5 shows an example of a beam profile in the laser treatment apparatus 100. FIG. 5 shows the energy of laser light obtained by a measuring instrument (power meter) disposed at a position 20 mm away from the top of the convex lens part 32 (the intersection of the surface of the convex lens part 32 and the extension of the axis of the optical fiber 2). An example of density is shown. In FIG. 5, the horizontal axis represents the distance R from the axis of the optical fiber 2. In the beam profile shown in FIG. 5, the energy density in a certain region (for example, a disk region having a diameter of 11 mm) is substantially constant. On the other hand, outside the certain region, the energy density decreases rapidly. As described above, according to the embodiment of the present disclosure, the top hat beam can be obtained relatively easily, so that uniform irradiation to the affected area can be realized. On the other hand, when the shape of the convex lens portion is a spherical lens shape, the beam profile is Gaussian, and the energy density changes smoothly with respect to the distance R from the axis of the optical fiber 2. That is, when the shape of the convex lens portion is a spherical lens shape, the beam emitted through the convex lens portion is not a top hat beam.

  Refer to FIG. 4 again. In the configuration illustrated in FIG. 4, the convex lens portion 32 is a part of the cap 30. That is, in this example, there is no clear boundary between the convex lens portion 32 and other portions (sometimes referred to as a main body portion) in the cap 30. If the convex lens portion 32 is formed as a part of the cap 30, there is no possibility that the convex lens portion 32 will drop off from other portions of the cap 30, which is beneficial.

  Further, in the embodiment of the present disclosure, by forming the cylindrical end portion of the cap 30 into a convex curved surface, a part of the cap 30 is used as the convex lens portion 32, so that blood adheres to the surface of the convex lens portion 32. However, blood can be easily removed. On the other hand, a conventional configuration in which a so-called GRIN lens (a lens configured so that the refractive index continuously changes along the axis) is fixed to the tip of an optical fiber using a ferrule (for example, a diagram in Patent Document 3). 1), the end face of the GRIN lens is located inside the end of the ferrule. For this reason, it is difficult to remove blood adhering to the end face of the GRIN lens.

When blood remains attached to the portion of the probe surface where the laser beam toward the outside of the probe passes (hereinafter sometimes referred to as “emission region” for convenience), by receiving the laser beam, The attached blood may char. Carbonized blood hinders the progress of the laser beam, and as a result, a sufficient amount of light may not be obtained. For these reasons, it is beneficial that the energy density of the laser light in the emission region is about 20 W / cm ² or less.

FIG. 6 shows the vicinity of the top of the convex lens portion 32 in an enlarged manner. As described above, the laser light generated by the laser light generator 20 (see FIG. 1) and incident on one end of the optical fiber 2 is emitted from the other end of the optical fiber 2. As schematically shown in FIG. 6, the laser light emitted from the other end of the optical fiber 2 travels while spreading in the cap 30 and is emitted from the surface of the convex lens portion 32. As can be seen from FIG. 6, in the embodiment of the present disclosure, the area of the portion of the surface of the convex lens portion 32 where the laser light is emitted (that is, the emission region) is larger than the diameter of the core of the optical fiber 2. Thus, by appropriately expanding the beam diameter between the end face of the optical fiber 2 and the convex lens portion 32, the energy density of the laser light in the emission region is appropriately reduced with respect to the energy density at the end face of the optical fiber 2. obtain. By reducing the energy density of the laser light in the emission region to about 20 W / cm ² or less, carbonization of blood adhering to the surface of the convex lens portion 32 can be suppressed.

FIG. 7 shows the relationship between the distance d from the end face of the optical fiber 2 to the top 32t of the convex lens portion 32 and the energy density of the laser light at the position of the top 32t. In FIG. 7, as an example, the measurement result of the energy density in the laser treatment apparatus 100 is indicated by a black circle. As shown in FIG. 7, in the embodiment of the present disclosure, the range of the distance d may be 1.2 mm <d <2.4 mm. At this time, the numerical aperture NA of the optical fiber 2 may be in a range of 0.2 <NA <0.3. The numerical aperture NA indicates the degree of spread of the laser light emitted from the optical fiber. The numerical aperture NA of the optical fiber 2 is, for example, not less than 0.24 and not more than 0.26. If the numerical aperture NA is larger than 0.2, it is beneficial because the irradiation area does not become too small. When the numerical aperture NA is smaller than 0.3, the top hat beam can be formed relatively easily. When the refractive index of air is 1, the numerical aperture NA can be obtained by the following equation (1). In formula (1), n ₁ and n ₂ represent the refractive index of the core and the refractive index of the cladding of the optical fiber 2, respectively.
NA = sin θ _A = n ₁ ² −n ₂ ² (1)

If the distance d from the end face of the optical fiber 2 to the top 32t of the convex lens part 32 is greater than 1.2 mm, the energy density of the laser light in the emission region can be reduced to about 20 W / cm ² or less, and the surface of the convex lens part 32 It is possible to suppress the carbonization of blood adhering to the surface. If the distance d is less than 2.4 mm, the outer diameter of the convex lens portion 32 does not become too large, and thus a small cap 30 can be realized. Accordingly, the probe 10 can be easily inserted into the biopsy port 517a (see FIG. 2) of the endoscope 505. The outer diameter of the convex lens part 32 may be 1.5 mm or less.

  In FIG. 7, a point corresponding to d = 0 (a point indicated by a black star) corresponds to an energy density measurement result in a conventional configuration (comparative example) using a GRIN lens. In the conventional configuration in which the GRIN lens is fixed to the end of the optical fiber, the area of the core on the end face of the optical fiber and the area of the emission region in the GRIN lens are substantially the same. That is, in the conventional configuration, the energy density of the laser light in the emission region is substantially equal to the energy density at the end face of the optical fiber 2. For this reason, the energy density of the laser beam in the emission region is relatively high. As a result, when blood adheres to the surface of the GRIN lens, blood carbonization tends to occur.

  FIG. 8 is a graph showing an example (Example) of a change in the output of the laser beam when blood is applied to the surface of the convex lens portion 32 and then the blood is wiped off. FIG. 9 is a graph showing an example (comparative example) of changes in the output of laser light when blood is wiped off after blood is applied to the surface of the GRIN lens in a conventional configuration having a GRIN lens. 8 and 9, the horizontal axis represents time, and the vertical axis represents the output of laser light emitted from the emission region. Specifically, first, the same amount of blood is applied to the surface of the convex lens portion 32 for the sample of the example, and the surface of the GRIN lens for the sample of the comparative example. Next, laser light is emitted from the optical fiber 2 in a state where blood is present on the emission region. If a rapid drop in output (80% drop here) is observed, the lens surface is wiped with cotton cotton or a cotton swab moistened with ethanol. Thereafter, the measurement is resumed. Both FIG. 8 and FIG. 9 show the measurement results for three samples.

  In the three examples shown in FIG. 8, the output is lowered after a while after the emission of the laser light from the optical fiber 2 is started. This is considered to be because a part of the blood on the emission region is carbonized. However, in these three examples, by wiping the surface of the convex lens portion 32, the output is restored to the same level as that immediately after the start of measurement. Furthermore, after the blood is wiped off, there is no reduction in output.

  On the other hand, in two of the three comparative examples shown in FIG. 9, the output drops to almost zero after a while after the emission of the laser light from the optical fiber 2 is started. This is considered to be because almost all of the blood on the emission region has been carbonized. For these two samples, the output did not recover even after wiping the blood. This is considered to be due to the fact that the carbonized blood is firmly attached to the surface of the GRIN lens and that the surface of the GRIN lens does not protrude with respect to the end face of the ferrule, so that sufficient wiping cannot be performed. Of the three comparative examples, the remaining one shows some recovery in output due to wiping off blood, but the output is greatly reduced compared to the level immediately after the start of measurement.

  As described with reference to FIG. 4, in the embodiment of the present disclosure, the convex lens portion 32 is formed as a part of the cap 30, and the surface of the convex lens portion 32 is a convex curved surface. Thereby, even if blood adheres to the surface of the convex lens part 32, the blood on the surface of the convex lens part 32 can be easily removed. In addition, by appropriately setting the distance from the end face of the optical fiber 2 to the top 32t of the convex lens portion 32, the energy density of the laser light in the irradiation region can be appropriately reduced. Thereby, the carbonization of the blood on the surface of the convex lens part 32 can be suppressed, and the output fall resulting from adhesion of blood can be suppressed. As is clear from the above description, in the embodiment of the present disclosure, the cap 30 is fixed to the optical fiber 2 via the adhesive 40, so that it is not necessary to fix a lens such as a GRIN lens using a ferrule. . Therefore, complicated assembly and alignment of a plurality of parts are not required, and the probe can be easily manufactured. In addition, since an expensive GRIN lens is not used, a relatively inexpensive probe can be provided.

(Second Embodiment)
FIG. 10 shows an example of a probe in a laser therapy apparatus according to another embodiment of the present disclosure. A probe 10A shown in FIG. 10 includes an optical fiber 2A and a cap 30A fixed to the tip of the optical fiber 2A via an adhesive 40.

  11 and 12 are a top view and a side view, respectively, showing an example of the appearance of the tip of the probe 10A when viewed from a direction perpendicular to the axis of the optical fiber 2A. Here, FIGS. 11 and 12 are respectively shown as a top view and a side view of the probe 10A, but are not intended to limit the orientation of the probe 10A when the probe 10A is used.

  10 to 12, the optical fiber 2A includes an optical fiber main body 2b including a core and a clad, and a jacket 2a that covers the side surface of the optical fiber main body 2b. However, the jacket 2a does not cover the side surface near the end of the optical fiber 2A.

  In this example, the hole portion 34A of the cap 30 is gradually cut from a portion having a diameter that is substantially the same as or slightly larger than the outer diameter of the jacket 2a and an end portion on the side where the optical fiber 2A is inserted toward the convex lens portion 32. A portion where the area decreases and a portion having a diameter that is substantially the same as or slightly larger than the outer diameter of the optical fiber main body 2b are included. As shown in the drawing, a portion of the hole 34A having a diameter that is substantially the same as or slightly larger than the outer diameter of the optical fiber main body 2b is a portion of the optical fiber 2A that is not covered with the optical fiber main body 2b by the jacket 2a. (Hereinafter may be referred to as “exposed portion”).

  In the second embodiment, a hole 36a reaching the side surface of the optical fiber 2A is formed on the side surface of the cap 30A. In this example, the hole 36a is provided at a position overlapping the exposed portion of the optical fiber 2A (see FIG. 11). As shown in FIG. 10, an adhesive 40 is present inside the hole 36a. In FIGS. 11 and 12, illustration of the adhesive 40 in the hole 36a is omitted in order to avoid complicated drawings.

  In the hole 34A, a portion other than the exposed portion of the optical fiber 2A is disposed in a portion having a diameter that is substantially the same as or slightly larger than the outer diameter of the jacket 2a. As described above, at least a part of the portion other than the exposed portion in the optical fiber 2A is disposed in the hole portion 34A of the cap 30A, so that the exposed portion in the optical fiber 2A and the hole portion of the cap 30A are disposed inside the cap 30A. A space 36b surrounded by the inner surface of 34A and the jacket 2a of the optical fiber 2A is formed. This space 36 b is filled with the adhesive 40.

  The hole 36a and the space 36b described above can store the adhesive 40 that couples the optical fiber 2A and the cap 30A. When the probe 10 is assembled, for example, the adhesive 40 is applied to the side surface of the distal end portion (typically an exposed portion) of the optical fiber 2A. And the front-end | tip part of the optical fiber 2A in the state to which the adhesive material 40 was apply | coated is inserted in the hole 34A of cap 30A. At this time, the excess of the adhesive 40 applied to the side surface of the tip of the optical fiber 2A is pushed toward the hole 36a or the space 36b, and at least a part of the space in the hole 36a and the space It satisfies at least a part of 36b.

  By providing a hole 36a reaching the side surface of the optical fiber 2A on the side surface of the cap 30A and filling the inside of the hole portion 36a with the adhesive 40, the optical fiber 2A and the cap 30A can be more strongly coupled. Even if air bubbles are mixed in the adhesive 40, the air bubbles can be released into the hole 36a together with the excess of the adhesive 40, and the optical fiber 2A and the cap 30A can be more strongly coupled. For example, a tensile strength of 20N or more can be realized. As used herein, “tensile strength” means the amount of force required to separate an optical fiber from a cap by pulling the optical fiber in a direction along the axis while the cap of the probe is fixed. In addition, the number, arrangement, shape, and size of the hole 36a can be arbitrarily set.

  Like the hole 36a, the space 36b is filled with the adhesive 40, so that the jacket 2a of the optical fiber 2A and the exposed portion of the optical fiber body 2b can be integrally joined to the cap 30A. Therefore, the optical fiber 2A and the cap 30A can be more strongly coupled. Even if bubbles are mixed in the adhesive 40, the bubbles can escape into the space 36 b together with the surplus of the adhesive 40.

  As described above, by providing the hole 36a and the space 36b, in assembling the probe 10A, the surplus portion of the adhesive 40 is pushed out into the hole 36a and the space 36b. Therefore, although the adhesive 40 remains between the end face of the optical fiber 2A and the bottom of the hole 34A, a uniform layer is formed by being pushed out into the hole 36a and the space 36b, and distortion of the beam profile is suppressed. Can do. As a result, loss of light quantity and / or deterioration of irradiation characteristics can be suppressed.

  The laser treatment apparatus according to the embodiment of the present disclosure is useful for PDT performed using an endoscope. The laser treatment apparatus of the present disclosure can be used for treatment of esophageal cancer, laryngeal cancer, and the like, for example.

2 Optical fiber 2a Jacket 20 Laser light generator 30 Cap 32 Convex lens part 34 Hole part 36a Second hole part 100 Laser treatment apparatus

Claims (8)

A laser treatment apparatus for an endoscope,
Optical fiber,
A laser light generator connected to one end of the optical fiber;
A cap formed of polyphenylsulfone having a hole for receiving the other end of the optical fiber, and a convex lens portion disposed along the extending direction of the hole;
A laser treatment apparatus comprising: an adhesive for coupling the cap to the other end of the optical fiber.   2. The laser treatment device according to claim 1, wherein an area of a portion of the surface of the convex lens portion from which the laser light generated by the laser light generator is emitted is larger than a diameter of a core of the optical fiber.   1.2 mm <d <2.4 mm and 0.2 <NA <0.3, where d is the distance from the other end of the optical fiber to the top of the convex lens portion, and NA is the numerical aperture of the optical fiber. The laser treatment apparatus according to claim 1 or 2, satisfying the relationship:   The laser treatment apparatus according to claim 1, wherein the convex lens portion has an aspherical shape.   The laser treatment apparatus according to claim 1, wherein the beam emitted through the convex lens portion of the cap is a top hat beam.   The laser treatment device according to claim 1, wherein the cap has a second hole portion that reaches a side surface of the optical fiber. The optical fiber has a jacket covering at least a part of the side surface of the optical fiber;
The other end of the optical fiber is an exposed portion not covered by the jacket;
The laser treatment apparatus has a space surrounded by the exposed portion, an inner surface of the hole in the cap, and the jacket,
The laser treatment apparatus according to claim 1, wherein the space is filled with the adhesive.   A photodynamic therapy device for esophagus comprising the laser therapy device according to claim 1.

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