Endoscope with bonded light guide

Abstract

A medical endoscope including: an elongated shaft with a distal end region having a non-circular cross-section and a shaft main section arranged proximally from the distal end region, an at least one light guide having a plurality of individual fibres disposed longitudinally through the shaft, wherein at least a portion of the plurality of individual fibres in the distal end region are bonded over a length of at least 50% of the distal end region with an inflexible adhesive.

Claims

1. A medical endoscope comprising: a main body; a rigid elongated shaft having a proximal end connected to a distal end of the main body, the elongated shaft having a distal end region with a non-circular cross-section and a shaft main section arranged between the distal end region and the distal end of the main body, and at least one light guide having a plurality of individual fibres disposed longitudinally through the shaft, wherein at least a portion of fibres of the plurality of individual fibres in the distal end region are bonded over a length of at least 50% of the distal end region with a single inflexible adhesive having a hardness so as to be grindable, the shaft main section has a round cross-section, the shaft main section has a greater circumference than a circumference of the distal end region, the at least one light guide within the distal end region is connected to a wall of the shaft with the inflexible adhesive; the inflexible adhesive has a Shore-D hardness of 75 or more; the inflexible adhesive is a two-component adhesive; and the inflexible adhesive seals the distal end region in one or more of a gas-tight manner and a liquid-tight manner.

2. The medical endoscope according to claim 1, wherein the distal end region has a length of 70-240 mm.

3. The medical endoscope according to claim 1, wherein the at least the portion of fibres of the at least one light guide in the distal end region are bonded over a length of at least 65% of the distal end region with the inflexible adhesive.

4. The medical endoscope according to claim 1, wherein the at least one light guide in the shaft main section passes through a tubing at least sectionally.

5. The medical endoscope according to claim 1, wherein the inflexible adhesive is an epoxy adhesive.

6. The medical endoscope according to claim 1, wherein the distal end region has a smaller diameter than a diameter of the shaft main section.

7. A method for assembling the medical endoscope according to claim 1, the method comprising: placing the inflexible adhesive within the distal end region of the shaft of the endoscope in at least one position, introducing the at least one light guide having the plurality of individual fibres into the shaft part, and one of curing the adhesive and allowing the adhesive to cure.

8. The medical endoscope according to claim 1, wherein the inflexible adhesive is an epoxy adhesive having a Shore-D hardness of 82.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Exemplary embodiments are shown schematically in the drawings, where:

(2) FIG. 1 illustrates a schematic side view of a urethroscope,

(3) FIG. 2 illustrates a section along line in FIG. 1 through the shaft main section of the shaft part,

(4) FIG. 3a illustrates a section along line IV-IV in FIG. 1 through a distal end region of the shaft part, wherein the shaft part has a working channel and an optics channel and the end region has a non-circular, oval cross-section, and

(5) FIG. 3b illustrates a section along a line IV-IV in FIG. 1 through a distal end region of an alternative shaft part, wherein the shaft part has two working channels and an optics channel and the end region has a non-circular, substantially triangular cross-section.

DETAILED DESCRIPTION

(6) FIG. 1 shows a side view of an endoscope 10 with a main body 11 and an elongated tubular shaft part 12 adjoining it distally, which is to be inserted into the patient's body. The main body 11 can, for example, comprise an eyepiece and an introductory part. The shaft part 12 and the main body 11 are connected to one another in a sealed manner in an unspecified manner, for example bonded, soldered or the like.

(7) In a connecting piece 13 on the main body 11, which is used to connect an external light guide, not shown, the proximal end of a light guide 18 shown in FIGS. 2 and 3 can be attached in the form of an optical fibre bundle which passes through the interior of the shaft part 12 in the longitudinal direction up to the distal end of the shaft part 12.

(8) In addition, an eyepiece socket 15 can extend from the main body 11, through which an optical system runs, which is also guided through the shaft part 12 to the distal end of the endoscope 10. At the proximal end of the optical system, an eyepiece can be provided on the eyepiece socket 15.

(9) The length of the shaft part 12 in an endoscope 10 of conventional design which, like the one shown, is configured as a urethroscope, is 400 to 500 mm, for example. The outer diameter of the shaft part 12, such as the outer diameter of the outer tube 19 of the shaft part 12, typically does not exceed a maximum of approximately 4 mm. In the case of such a diameter of the outer tube 19, it results that, substantially regardless of the wall thickness, there is a certain stiffness of the tube, which, when the tube is bent, leads to an elongation of the material on the outside and a compression of the material on the inside (based on the centre point of the bending radius).

(10) In the shaft part 12 of the endoscope 10 shown in FIG. 1, the distal end region 14 is formed with a smaller outer diameter and circumference than the shaft main section 16 arranged proximally therefrom. As a result, the distal end region 14 can be guided to the surgical site in a particularly gentle manner. The distal end region 14 has a length of approximately 10 cm.

(11) At its distal end, the shaft part 12 or the distal end region 14 is sealed in a suitable manner, for example, with a window for optics in the optics channel 22 shown in FIGS. 2 and 3 and with a sufficiently tight bonding of the light guide(s) 18 shown in FIGS. 2 and 3. The bonding at the distal end is usually performed, for example, using an inflexible adhesive. The well-sealed shaft part 12 ensures that the optics arranged in the interior and the light guide(s) 18 are not impaired by water or steam penetrating when working with the endoscope 10 or during sterilization. Furthermore, the inflexible bonding in the distal end region 14 is continued over the entire length of the distal end region 14. This serves on the one hand to protect the light guide(s) 18 shown in FIGS. 2 and 3 and on the other hand to provide even better gas- and liquid-tight sealing of the shaft part 12.

(12) The cross-sectional illustration 17 of FIG. 2 shows that the shaft part 12 in a shaft main section 16 has a shaft wall 20 which has a round cross-section and which can be configured as a metal tube. The shaft main section 16 and the distal end region 14 are elastically deformable, i.e. reversibly flexible, and can therefore deform flexibly during the surgical procedure.

(13) The interior of the shaft part 12 enclosed by this shaft wall 20 accommodates two inner channels in the exemplary embodiment shown, the optics channel 22 and the working channel 30. Both the optics channel 22 and the working channel 30 can be configured as metal tubes, for example with corresponding walls 28 made of metal, for example, steel. The optics channel 22 encloses the optics, which transmits the viewed image from a lens arranged at the distal end of the shaft part 12 to the eyepiece. The working channel 30 is configured as a free channel in which an instrument (for example, a laser lithotriptor) can be advanced through a connection piece (not shown, the proximally provided laser generator of which is also not shown).

(14) In the interior of the shaft part 12, two light guides 18 are also laid, which can be configured as optical fibre bundles, and serve to illuminate the field of view. The light guides 18 are sheathed in the embodiment shown with a flexible shrinkage tubing 32 made of silicone, which protects the light guides 18 from damage caused by pressure and friction. Alternatively, it is also possible to protect the light guides 18 in each case by bonding with a flexible adhesive, such as a silicone adhesive. With such an adhesive, however, the possible interactions between different types of adhesive must be taken into account when assembling instruments.

(15) At the proximal end of the shaft part 12, the light guide 18 can be led out of the main body 11 via a light guide connection. There, an optical fibre connection cable can be connected to a cold light source, not shown.

(16) FIG. 3a and FIG. 3b each show a cross-section 17 through a distal, non-circular end region 14 of different shaft parts 12.

(17) It can be seen that the shaft part 12 shown in FIG. 3a has a substantially oval outer cross-section in a distal end region 14, while—as can be seen in the background of FIG. 3a—proximally from this end region 14 it has a shaft main section 16 with a round outer cross-section. The shaft part 12 shown in FIG. 3a is part of a 1-channel instrument, since the shaft part 12 clearly has a single working channel 30.

(18) It can also be seen that the shaft part 12 shown in FIG. 3b has a substantially triangular outer cross-section with rounded corners in its distal end region 14, while—as can be seen in the background of FIG. 3b—proximally from this end region 14 it has a shaft main section 16 with a round outer cross-section. The shaft part 12 shown in FIG. 3b is part of a 2-channel instrument, since the shaft part clearly has two working channels 30.

(19) Due to the oval or triangular outer cross-section of the distal end region 14, the distal end region 14 of the shaft part 12 shown in each case has a circumference which is significantly reduced compared to the shaft main section 16.

(20) In addition to the working channel(s) 30, the shaft parts 12 have an optics channel 22, into which optics can be drawn. A dilation nose 24 is also arranged on the shaft part 12. It can be seen that the light guides 18 substantially fill the entire free space within the shaft part 12. The light guides 18 are bonded with an inflexible epoxy adhesive for protection against breaking and protection against friction. For bonding, portions of the adhesive can be placed on the inside of the shaft wall 20 at a plurality of positions of the respective end region 14 and then the optics channel 22, working channel(s) 30 and the light guides 18 were introduced into the outer tube 19. The epoxy adhesive was then allowed to cure. The adhesive can be applied over the entire length of the distal end region 14 or a portion thereof.

(21) While there has been shown and described what is considered to be preferred embodiments of the invention, it will, of course, be understood that various modifications and changes in form or detail could readily be made without departing from the spirit of the invention. It is therefore intended that the invention be not limited to the exact forms described and illustrated, but should be constructed to cover all modifications that may fall within the scope of the appended claims.

LIST OF REFERENCE NUMERALS

(22) 10 endoscope 11 main body 12 shaft part 13 connecting piece 14 distal end region 15 eyepiece 16 shaft main section 17 cross-section shaft part 18 light guide 19 outer tube 20 shaft wall 22 optics channel 24 dilation nose 26 inflexible adhesive 28 wall of the working channel 30 working channel 32 shrinkage tubing