JP2018102840A - Endoscope distal hood - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve visibility of an endoscopic image in an endoscope distal hood having an optical filter.SOLUTION: An endoscope distal hood 1 is mounted on a distal end 21a of an endoscope 2 including an imaging part 21c, and is composed of a substantially cylindrical member. The distal hood 1 includes: an endoscope mount part 11 to be mounted on the distal end 21a of the endoscope 2; and a hood part 12 formed at an opposite side of the endoscope mount part 11, along the axial center AX. The hood part 12 includes: an optical filter 13; a substantially plate-like support part 14 supporting the optical filter 13 so as to cover the imaging part 21c, with it mounted on the endoscope 2; and a sealing part (an O ring) 15 provided at a surface of the support part 14, at a distal end side of the endoscope 2 so as to enclose the optical filter 13 and sealing a part between the imaging part 21c and the optical filter 13.SELECTED DRAWING: Figure 3A

Description

  The present invention relates to a tip hood attached to a tip portion of an endoscope.

  Recently, photodynamic diagnosis (PDD) and photodynamic therapy (PDT) using photosensitivity substances that accumulate in cancer and photochemical reaction caused by laser light irradiation have attracted attention. Has been.

  PDD is a diagnostic method for identifying a lesioned part by irradiating a photosensitizer selectively accumulated in cancer cells with a laser beam having a specific wavelength, observing fluorescence emitted from the photosensitizer. PDT is a treatment method in which excited oxygen is generated by irradiating a photosensitive substance selectively accumulated in cancer cells with laser light of a specific wavelength, thereby killing the cancer cells. PDD is expected as a therapeutic method for accurately detecting the extent of a lesion under an endoscope, and PDT is expected as a minimally invasive cancer therapeutic method with very little damage to normal tissues.

  When performing PDD or PDT under the endoscope, a tip hood is attached to the tip of the endoscope, the endoscope is inserted to the vicinity of the lesion, and an endoscope forceps channel (treatment instrument guide tube) Then, a probe for emitting laser light is inserted. Point the probe tip toward the lesion, hold the lesion (the wall to be treated by the luminal organ) at or near the lesion with one end of the tip hood, and keep the posture and distance of the probe tip relative to the lesion properly. Irradiate light.

  By the way, when performing PDD and PDT using a general endoscope, it may be necessary to provide an optical filter in the imaging unit of the endoscope. For example, in PDD using protoporphyrin IX generated in vivo by administration of 5-aminolevulinic acid or the like as a photosensitizer, the fluorescence emitted from protoporphyrin IX is naturally reflected in the diffuse reflection of laser light used for irradiation or in vivo. In order to eliminate the influence of fluorescence (autofluorescence) emitted from other fluorescent substances contained in the optical filter, an optical filter that transmits only light having a wavelength of about 635 nm emitted from protoporphyrin IX is used. As a method of providing such an optical filter in an imaging unit of an endoscope, a method of attaching a tip hood having an optical filter to the endoscope has been proposed (see Patent Document 1). However, the tip hood having the conventional optical filter has a problem that body fluid or the like may enter between the optical filter and the imaging unit of the endoscope, thereby reducing the visibility in the endoscopic image.

JP 2007-20759 A

  The present invention has been made in view of such a situation, and an object thereof is to improve the visibility of an endoscopic image in an endoscope front end hood having an optical filter.

In order to achieve the above object, an endoscope tip hood according to the present invention includes:
A tip hood for an endoscope, which is attached to the tip of an endoscope having an imaging unit and is made of a substantially cylindrical member,
An endoscope mounting portion mounted on a distal end portion of the endoscope;
A hood formed on the opposite side along the axis of the endoscope mounting portion;
An optical filter section;
A substantially plate-like support part that supports the optical filter part so as to cover the imaging part in a state of being attached to the distal end part of the endoscope;
A sealing portion that is provided on a surface of the support portion on the distal end side of the endoscope so as to surround the optical filter portion and seals a portion between the imaging portion and the optical filter portion. .

  In the distal end hood for an endoscope according to the present invention, the support part that supports the optical filter part is provided on the surface on the distal end part side of the endoscope so as to surround the optical filter part, and between the imaging part and the optical filter part. Since the sealing part which seals this part is included, it is suppressed that a bodily fluid etc. permeate into the part between an imaging part and an optical filter part. Therefore, the visibility of the endoscopic image (image captured by the imaging unit) can be improved.

FIG. 1A is a perspective view of a distal end hood for an endoscope according to an embodiment of the present invention. 1B is a front view of the distal end hood for an endoscope shown in FIG. 1A. 1C is a cross-sectional view taken along the line Ic-Ic of the endoscope front end hood shown in FIG. 1A. FIG. 1D is an enlarged cross-sectional view showing a main part of the endoscope distal end hood shown in FIG. 1A. FIG. 2 is a perspective view showing the vicinity of the distal end portion of the endoscope to which the endoscope distal end hood shown in FIG. 1A is attached. 3A is a side sectional view showing a state in which the endoscope distal end hood shown in FIG. 1A is attached to the distal end portion of the endoscope shown in FIG. FIG. 3B is a partial cross-sectional view showing an enlarged main part of FIG. 3A. FIG. 4A shows the position of the distal end of the endoscope to which the distal end hood for an endoscope shown in FIG. 1A is attached with respect to the diagnostic site of the luminal organ, and irradiates the laser beam from the probe inserted into the forceps channel. It is a figure which shows typically the state which carried out. FIG. 4B shows a probe inserted into a forceps channel by positioning the distal end portion of an endoscope to which a distal end hood for an endoscope according to another embodiment of the present invention is attached with respect to a diagnostic site of a luminal organ. It is a figure which shows typically the state which irradiated the laser beam.

  Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment An endoscope distal end hood according to an embodiment of the present invention is used by being attached to the distal end portion of an endoscope. The endoscope front hood can be suitably used for an endoscope used for photodynamic diagnosis (PDD) or photodynamic therapy (PDT). Below, the case where the presence range of the lesion (cancer) of the esophagus as a luminal organ is diagnosed by PDD using protoporphyrin IX as a photosensitizer will be described as an example.

  As shown in FIG. 1A, FIG. 1B, FIG. 1C, and FIG. 1D, the distal end hood 1 for an endoscope consists of a substantially cylindrical member as a whole, and the distal end portion 21 ( It has an endoscope mounting part 11 that is externally fitted to (see FIG. 2 and FIG. 3A), and has a hood part 12 on the tip side.

  The hood portion 12 has a tip opening edge portion 12a at the tip, and in this embodiment, the tip opening edge portion 12a has a circular shape. That is, the tip opening edge portion 12a is a circular opening cut by a plane substantially orthogonal to the axis AX. In the present embodiment, the axis AX is an axis of a substantially cylindrical member, and the endoscope mounting portion 11 and the hood portion 12 are located on the opposite sides along the axis AX. The proximal end of the hood portion 12 (in the vicinity of the endoscope mounting portion 11) penetrates inside and outside as a discharge port for preventing body fluid such as saliva and gastric fluid from accumulating inside the hood portion 12. A through hole 12b is formed. In addition, a concave groove, a mark, or the like is formed on the inner surface of the hood portion 12 as a mark for aligning the position around the axis AX with the distal end portion of the endoscope 2 (see FIGS. 2 and 3A). May be.

  An optical filter (optical filter portion) 13 is provided inside the hood portion 2. The optical filter 13 is supported by a plate-like filter support part (support part) 14. When the filter support unit 14 is attached to the distal end portion of the endoscope 2, the filter support unit 14 supports the optical filter 13 so as to cover an imaging unit 21 c (see FIGS. 2, 3 </ b> A, and 3 </ b> B) described later. It is a part or member. The through hole 12b described above is provided in a portion of the wall surface of the hood portion 12 that is close to the optical filter.

  One end and the other end of the filter support portion 14 are integrated with a portion of the hood portion 12 on the base end side (opposite the distal end opening edge portion 12a) (a boundary portion with the endoscope mounting portion 11). It is provided in connection with. The plate surface of the filter support portion 14 is set so as to be substantially orthogonal to the axis AX. In the present embodiment, the filter support portion 14 is formed so as not to cover illumination portions 21d and 21d (see FIG. 2) to be described later, and corresponds to a distal end opening 21b (see FIG. 2) of a forceps channel to be described later. A through hole 14a is formed in the portion.

  When performing PDD using protoporphyrin IX as a photosensitizer, laser light having a wavelength of about 405 nm is inserted into the forceps channel of the endoscope 2 and protrudes from the tip opening 21b of the forceps channel (wavelength around 405 nm). Diagnostic light) is emitted. And by this excitation with laser light, Protoporphyrin IX emits fluorescence with a wavelength of about 635 nm, and at the same time, a fluorescent substance present in normal tissue may emit fluorescence with a wavelength of about 500 nm (autofluorescence). Therefore, as the optical filter 13 provided in the tip hood 1 used in this case, the fluorescence of the protoporphyrin IX to be observed can be transmitted, and the diffused diagnostic light and the fluorescence emitted by the fluorescent substance other than the protoporphyrin IX can be blocked. In other words, a long-pass filter or a band-pass filter that transmits light in the vicinity of a wavelength of 635 nm and blocks light having a wavelength shorter than that is used.

  As the optical filter 13, an optical thin film formed on a base material made of transparent glass, resin, or the like, which is supported and fixed to the filter support portion 14, or a corresponding part of the filter support portion 14 may be used. Alternatively, the whole may be a transparent member, and an optical thin film may be formed on part or all of the corresponding filter support portion 14.

  An O-ring 15, which is an annular seal member, is provided on the surface of the filter support portion 14 on the distal end portion 21 a side of the endoscope 2 as a sealing portion that seals a portion between the imaging portion 21 c and the optical filter 13. The annular filter groove 14b (see FIGS. 1B and 1D) is formed in the filter support portion 14 so as to surround the outside of the optical filter 13, and the annular groove 14b An O-ring 15 is inserted and arranged. As the material of the O-ring 15, a material having rubber elasticity is preferably used, and specific examples include nitrile rubber, ethylene propylene rubber, fluorine rubber, and silicone rubber. Among these, silicone rubber can be suitably used from the viewpoint of excellent light resistance.

  The inner diameter d1 of the endoscope attachment portion 11 is set in relation to the outer diameter of the distal end portion of the endoscope 2 to which the endoscope attachment portion 11 is attached, and is preferably about φ4 to 12 mm. The inner diameter d2 of the hood portion 12 is not particularly limited, but is preferably approximately the same as the inner diameter d1.

  The dimension (protrusion length from the distal end surface of the endoscope) L1 in the longitudinal direction (direction along the axis AX) of the hood portion 12 shown in FIG. 1C depends on the treatment using the endoscope to which the hood portion 12 is attached. However, in this embodiment, it is preferably about 5 to 30 mm as used for PDD. The dimension L2 in the longitudinal direction (direction along the axis AX) of the endoscope mounting portion 11 is preferably set to about 2 to 20 mm.

  The endoscope mounting portion 11 and the hood portion 12 may be integrally formed of the same material at the same time, or may be formed as separate members and then integrated with each other. In the present embodiment, the endoscope mounting portion 11 and the hood portion 12 are separately molded and then fitted and fixed to be integrated. Further, a part of the endoscope mounting part 11 on the hood part 12 side and a part of the endoscope mounting part 11 on the opposite side to the hood part 12 are separate members, and the hood part 12 of the endoscope mounting part 11 is used. A part of the side may be integrally formed of the same material as the hood part 12 at the same time, and a part of the endoscope mounting part 11 opposite to the hood part 12 may be integrally formed therewith.

  The hood portion 12 may be made of a transparent or translucent material so that the inside thereof can be visually recognized, or may be made of a light-shielding material in order to suppress light leakage from the inside. . When the hood portion 12 is provided with light shielding properties, the hood portion 12 is made of a material that does not have light shielding properties, and an additional tape or the like having light shielding properties is applied around it, or a light shielding paint is applied. By applying, light shielding properties may be imparted.

  Moreover, the hood part 12 may have a part or all of the front end part side having flexibility. The endoscope mounting portion 11 may have flexibility similar to the hood portion 12 on the condition that the function of reliably fixing to the distal end portion of the endoscope is not impaired. As a material constituting the endoscope mounting portion 11 and / or the hood portion 12, polycarbonate resin, polyacetal resin, silicone rubber, ethylene propylene rubber, various thermoplastic elastomers, and the like can be used.

  Next, an endoscope (electronic endoscope) to which an endoscope tip hood according to an embodiment of the present invention is attached will be outlined with reference to FIG. The endoscope 2 includes an insertion portion 21 made of a flexible tubular member having a distal end portion 21a inserted into the body (inside a luminal organ such as the esophagus) and a proximal end portion (not shown) disposed outside the body. And an operation unit (not shown) arranged at the proximal end of the insertion unit 21 and the like. The operation part is provided with an operation knob or the like for deflecting the distal end part 21a of the insertion part 21 and its vicinity.

  Although not shown in the drawing, the treatment tool guide for inserting various endoscope treatment tools (in this embodiment, the laser probe 3 used as a light source for PDD) is omitted. A forceps channel as a tube, a wiring channel through which electrical wiring or the like to a CCD (imaging device) provided at the distal end of the insertion portion 21 is inserted, a fiber channel through which an optical fiber for illumination (light guide) is inserted, A suction channel for sucking a gas or a liquid, a water supply channel for injecting a chemical solution or the like, an air supply channel for sending air or the like are formed.

  The distal end portion 21a of the insertion portion 21 is provided with a distal end opening 21b communicated with the forceps channel, an imaging portion 21c, and illumination portions 21d and 21d that emit illumination light from the distal end of the optical fiber inserted into the fiber channel. Yes. Although not shown, the distal end portion 21a of the insertion portion 21 is also provided with a suction channel, a water supply channel, and a suction port, a water supply port, and an air supply port corresponding to the air supply channel. As shown in FIG. 3A, the imaging unit 21c includes an objective lens system 21c1 and a color filter type CCD (imaging device) 21c2.

  As shown in FIG. 3A, the distal end hood 1 for an endoscope according to the present embodiment is attached to the distal end portion 21a of the insertion portion 21 of the endoscope 2. The tip hood 1 is inserted by winding and affixing a sterilized elastic plastic tape (not shown) or the like in a state where the endoscope mounting portion 11 is externally fitted to the tip portion 21a of the insertion portion 21. It is fixed (attached) to the tip 21 a of the part 21.

  The laser probe 3 is inserted into the forceps channel from the operation unit side of the endoscope 2 in order to irradiate the diagnostic site in the hollow organ with the laser light for PDD. The laser probe 3 includes a flexible tube having a distal end and a proximal end, an optical fiber (light guide) inserted through the tube, and a laser beam provided at the distal end of the tube and transmitted by the optical fiber. And a laser beam emitting section that emits light. The proximal end of the optical fiber is connected to a semiconductor laser generator not shown.

  The tip of the laser beam emitting portion of the laser probe 3 inserted into the forceps channel is disposed in the vicinity of the tip opening 21 b on the tip surface of the insertion portion 21. In a semiconductor laser generator outside the figure, a laser beam having a wavelength (for example, a wavelength of 405 nm) optimum for PDD is generated to excite the fluorescence of protoporphyrin IX, and the laser beam is emitted from the laser beam emitting portion at the tip of the laser probe 3. It is emitted from.

  Next, an outline of the PDD using the endoscope distal end hood 1 according to the above-described embodiment will be described.

  First, the endoscope distal end hood 1 according to the present embodiment is attached to the distal end 21 a of the insertion portion 21 of the endoscope 2. That is, the distal end portion 21 a of the insertion portion 21 of the endoscope 2 is inserted from the proximal end portion side of the endoscope mounting portion 11 of the distal end hood 1, and the endoscope mounting portion 11 is externally attached to the distal end portion 21 a of the insertion portion 21. Fit.

  When the endoscope mounting portion 11 is inserted into the distal end portion 21a of the insertion portion 21, the endoscope distal end hood 1 is appropriately rotated relatively around the axis AX so that the optical filter 13 is inserted into the insertion portion 21. The position in the rotational direction is adjusted so as to correspond to the imaging portion 21c on the distal end surface (or the through hole 14a corresponds to the distal end opening 21b). In addition, when there exists a mark on the inner surface of the hood part 12, you may match the position of a rotation direction using this mark.

  Next, as shown in FIG. 3B, the distal end portion 21a (tip end surface) of the insertion portion 21 is brought into pressure contact with the filter support portion 14 of the hood portion 1, and the O-ring 15 is compressed toward the annular groove 14b. In this state, a plastic tape (not shown) is wound and pasted on a portion including a joint portion between the endoscope mounting portion 11 and the distal end portion 21a of the insertion portion 21, and the distal end hood 1 is attached to the distal end portion 21a of the insertion portion 21. Secure to.

  Protoporphyrin IX is inserted into the insertion part 21 of the endoscope 2 to which the tip hood 1 is attached, where 5-aminolevulinic acid or the like has been previously administered (oral administration, intravenous injection, etc.) to cause a lesion (cancer cell). Is inserted from the patient's mouth that has been selectively accumulated, and the distal end portion 21a of the insertion portion 21 is inserted to the site to be diagnosed (diagnosis location 4) while monitoring the image captured by the imaging portion 21c. .

  In this state, as shown in FIG. 4A, a part of the distal end opening edge 12a of the hood part 12 is abutted against a part of the periphery of the diagnosis location 4, the posture of the distal end part 21a of the insertion part 21 is adjusted, and the hood The distal end opening edge 12 a of the portion 12 is arranged in the vicinity of the diagnosis location 4. Next, the laser probe 3 that emits laser light having a wavelength of about 405 nm is inserted into the forceps channel, and the tip of the laser light emitting portion of the laser probe 3 is projected from the tip opening 21 b on the tip surface of the insertion portion 21.

  Next, laser light L having a wavelength of about 405 nm is emitted from the light emitting portion of the laser probe 3, and the irradiated portion is imaged by the imaging portion 21 c while irradiating the diagnostic location 4, and the obtained endoscopic image is monitored. At this time, when cancer cells are generated in the diagnosis location 4, protoporphyrin IX selectively accumulated in the cancer cells emits red fluorescence having a wavelength of about 635 nm. The imaging unit 21c of the endoscope 2 captures an endoscopic image through the optical filter 13 that transmits light having a wavelength of around 635 nm and blocks light having a wavelength of less than 635 nm. The fluorescence of protoporphyrin IX can be observed by eliminating the influence of autofluorescence of normal cells. Therefore, it can be diagnosed that the part where the light is observed in the diagnosis part 4 is a part where cancer cells are generated. When the diagnosis location 4 is wider than the laser light irradiation range, the portion of the front opening edge 12a of the hood 12 that contacts the periphery of the diagnosis location 4 is shifted along the inner wall surface of the diagnosis location 4. The same operation may be repeated.

  In the above-described embodiment, the annular groove 14b and the O-ring 15 are provided on the surface of the filter support portion 14 on the distal end portion 21a side of the endoscope 2 so as to surround the optical filter 13, and the O-ring 15 is disposed in the annular groove 14b. In a compressed state, the distal end hood 1 is attached to the distal end portion 21 a of the endoscope 2. Since the portion between the imaging unit 21c and the optical filter 13 is hermetically sealed by the O-ring 15, intrusion of body fluid or the like into the portion between the imaging unit 21c and the optical filter 13 is suppressed. Therefore, the visibility of the endoscopic image (image captured by the imaging unit 21c) can be improved. Note that a gap space may exist between the imaging unit 21c and the optical filter 13 as long as the gap space is sealed from the outside.

Second Embodiment Next, a modification of the above-described embodiment will be described with reference to FIG. 4B. In this modification, components that are substantially the same as those in the above-described embodiment will be denoted by the same reference numerals, description thereof will be partially omitted, and differences will be described.

  In this modification, as the hood portion 12, the tip opening edge portion 12 a has an elliptical inclined edge portion that is inclined at a predetermined angle θ with respect to the axis AX of the tip hood 1. That is, the tip opening edge portion 12a has an elliptical inclined edge portion obtained by cutting a substantially cylindrical member along a plane oblique to the axis AX at a predetermined angle θ, It has become. Although it does not specifically limit as inclination-angle (theta), Preferably it is 20-60 degrees.

  According to this modification, the hood part 12 has the tip opening edge part 12a which consists of the inclined edge part which inclines with the predetermined angle (theta) with respect to the axial center. Therefore, the endoscope is adjusted by adjusting the posture of the distal end portion 21a of the endoscope 2 so that the inclined edge abuts around the diagnosis location 4 (the wall surface portion to be diagnosed of the luminal organ). The posture of the two distal end portions 21a can be stabilized. In addition, in order to make the front-end | tip opening edge part 12a contact | abut along the periphery of the diagnostic location 4, you may suck | inhale the gas in the front-end | tip hood 1 via an intake channel.

  In this modification, an alignment mark portion may be provided at a position corresponding to the most protruding portion of the tip opening edge portion 12a on the inner surface of the hood portion 12. With this configuration, when the distal end hood 1 is mounted on the distal end portion 21a of the endoscope 2, the landmark portion is used as a landmark around the axis of the distal end hood 1 with respect to the distal end portion 21a of the endoscope 2. The alignment can be easily performed.

  In this modification, it is preferable that the hood part 12 has a light shielding property. By comprising in this way, it can suppress that light leaks from the inside of the food | hood part 12 to the exterior. That is, the laser light L emitted from the laser light emitting portion of the laser probe 3 or its reflected light can be prevented from leaking from the hood portion 12 to the outside. For this reason, it is possible to effectively prevent the laser light from being irradiated to a portion that is not intended to be irradiated. Further, at least the tip opening edge portion 12a may have flexibility. By configuring in this way, it becomes easier to bring the tip opening edge 12a of the hood 12 into close contact with the periphery of the diagnosis location 4.

  In the above-described embodiment, the hood portion 12 is a substantially cylindrical member. However, the hood portion 12 may be a substantially frustoconical cylindrical member that is widened or tapered. Further, the hood portion 12 may have a cylindrical shape other than a cylinder.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above-described embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention. For example, in the above-described embodiment, in order to perform PDD using protoporphyrin IX as a photosensitive substance, as the optical filter 13, a long-pass filter that transmits light having a wavelength of about 635 nm and blocks light having a wavelength shorter than that is used. Alternatively, the case where a band-pass filter is used has been described. However, the tip hood for an endoscope of the present invention can also be used for an endoscope for performing other diagnosis / treatment such as PDT. Can be appropriately selected according to the diagnosis and treatment to be performed.

DESCRIPTION OF SYMBOLS 1 ... Endoscope hood for endoscopes 11 ... Endoscope mounting part 12 ... Hood part 12a ... Edge opening edge part 13 ... Optical filter (optical filter part)
14 ... Filter support part (support part)
14a ... through hole 14b ... annular groove 15 ... O-ring (sealing part)
2 ... Endoscope 21 ... Insertion part 21a ... Tip part 21c ... Imaging part 21c1 ... Objective lens system 21c2 ... CCD
3 ... Laser probe 4 ... Diagnosis location of luminal organ

Claims (1)

A tip hood for an endoscope, which is attached to the tip of an endoscope having an imaging unit and is made of a substantially cylindrical member,
An endoscope mounting portion mounted on a distal end portion of the endoscope;
A hood formed on the opposite side along the axis of the endoscope mounting portion;
An optical filter section;
A substantially plate-like support part that supports the optical filter part so as to cover the imaging part in a state of being attached to the distal end part of the endoscope;
A sealing portion that is provided on a surface of the support portion on the distal end side of the endoscope so as to surround the optical filter portion and seals a portion between the imaging portion and the optical filter portion. Endoscope hood for endoscope.

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