WO2005058147A1

WO2005058147A1 - Flexible protective sheath for an endoscope

Info

Publication number: WO2005058147A1
Application number: PCT/EP2003/051066
Authority: WO
Inventors: John B. Foster
Original assignee: Patents Exploitation Company B.V.
Priority date: 2003-12-18
Filing date: 2003-12-18
Publication date: 2005-06-30
Also published as: AU2003299257A1

Abstract

In an endoscopic device (1), a flexible protective sheath for a rigid or flexible endoscope (2) is defined by a tube (12) made of transparent elastomeric material and having an open first end (12a) for insertion of one end of the rigid or flexible endoscope (2); and by a cap portion (14) defining a view window and made in one piece with the tube (12).

Description

FLEXIBLE PROTECTIVE SHEATH FOR AN ENDOSCOPE

TECHNICAL FIELD The present invention relates to a protective sheath for rigid or flexible endoscopes. BACKGROUND ART

In diagnosis and surgery, rigid or flexible endoscopes are used, which can be inserted inside a patient's body to visualize a tissue portion of the body.

A known rigid or flexible endoscope comprises a rigid or flexible tubular body, one end of which is fitted integrally with a lens; an end member normally connected to one end of the rigid or flexible tubular body and having an eyepiece; and optical means, such as an optical fibre bundle, which extend inside the rigid or flexible tubular body up to the end fitted with the lens, and are connectable, in use, to an external light source for illuminating the monitored tissue. To keep the endoscope clean and sterile, flexible sheaths have been introduced, which comprise a flexible tube fitted integrally at one end with a transparent window which, in use, is placed over the endoscope lens. In flexible sheaths of the above type, the cross section of the tube is approximately equal to but no smaller than that of the tubular body of the endoscope, so that, when inserting the tubular body of the endoscope inside the sheath, air binds are frequently formed, thus preventing the endoscope lens from contacting the transparent window of the sheath, and so resulting in a blurred image. Precise endoscopic examination is also impaired if the various component parts are not perfectly clean or dry, in which case, condensation is likely to form. Moreover, flexible sheaths of the type described are known to be made of polyethylene material, which is relatively inflexible and has the drawback of forming creases when orienting the distal portion of the sheath, thus causing considerable discomfort to the patient and possibly also accidental lesions. The creases also constitute actual air pockets in which condensation can form.

To eliminate the above drawbacks, new sheaths have been devised, as described in Patent Application TO2001A000900, and which comprise an elongated flexible tube larger in diameter than the endoscope and made of a particular elastomeric material; a transparent window connected integrally to a first end of the tube; and an annular gripping member connected integrally to a second end of the tube and made of more rigid material than the tube itself.

Given the elasticity of the particular elastomeric material used, this type of sheath enables the tube to adhere perfectly (without creasing) to the tubular body of the endoscope, so that air is evacuated easily when inserting the tubular body.

Moreover, a sheath of this type ensures the transparent window substantially contacts the endoscope lens, thus preventing the formation of condensation and so enabling a clear, accurate endoscopic examination at all times.

Though technologically innovative and indeed solving the problems referred to above, this type of sheath has the drawback of the transparent window being glued to the tube, which inevitably results in the formation of a thickened portion of the sheath, with obvious disadvantages when inserting the sheathed endoscope inside the patient's body.

Another disadvantage of the sheaths described in Patent Application TO2001A000900 lies in the window of the sheath being designed for a specific type of endoscope lens. As such, the same type of sheath cannot be used for different endoscopes with different types of lenses, thus resulting in manufacturing drawbacks.

DISCLOSURE OF INVENTION

It is an object of the present invention to provide a protective sheath for a rigid or flexible endoscope, designed to provide a relatively straightforward, low- cost solution to the aforementioned drawbacks.

According to the present invention, there is provided a protective sheath for a rigid or flexible endoscope, as claimed in Claim 1.

BRIEF DESCRIPTION OF THE DRAWING

A non-limiting embodiment of the invention will be described by way of example with reference to the accompanying drawing, which shows a partly sectioned side view of an endoscopic device comprising a flexible protective sheath in accordance with the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Number 1 in the accompanying drawing indicates as a whole an endoscopic device. Device 1 comprises a known rigid endoscope 2 used, for example, for artoscopy, cystoscopy, laparoscopy, otorhinoscopy, etc., and in turn comprising a rigid tubular body 3, a first end 3a of which is fitted integrally with a view window 4 with a lens 5, and a second end 3b of which is fitted integrally with an end member 6 normally comprising an eyepiece 7 and a connector 8 connectable to a light source. First end 3a is normally connected to end member 6 by an optical fibre bundle or a series of in-line optical prisms (not shown) located inside tubular body 3, and which, in use, provide for illuminating and viewing a region close to end 3a. Second end 3b of tubular body 3 has a fitting 9 comprising two radial projections 10 for the purpose described later on.

Device 1 also comprises a protective sheath 11 for housing tubular body 3.

Sheath 11 comprises a tube 12; an annular gripping member 13 fitted integrally to a first end 12a of tube

12; and a cap portion 14 located at and formed in one piece with a second end 12b of tube 12.

Cap portion 14, in use, constitutes a window for view window 4 fitted to tubular body 3, and, in particular, is positioned contacting, and molds itself over, lens 5.

For which purpose, cap portion 14 must be made of material which is both transparent, to allow a clear view of the monitored tissue through cap portion 14, and is elastic and deformable enough for cap portion 14 to mold itself correctly over lens 5 fitted to tubular body 3.

Tube 12 and cap portion 14 are the same thickness, and are made of materials selected from the group comprising silicone rubber, polyurethane rubber, butadiene-styrene rubber, styrene-ethylene rubber, PVC, polyurethane, polyethylene, silicone, and mixtures of these. In a preferred embodiment, tube 12 and cap portion

14 are made of an elastomeric material known by the trade name Elastosil®, the properties of which enable correct production of tube 12 and cap portion 14 by injection.

Tube 12 is slightly larger in diameter than tubular body 3, so that air is evacuated when inserting tubular body 3. Annular gripping member 13 has an inner annular groove 15 sized to house projections 10, in accordance with a mechanism described in Patent Application

TO2001A000900. In actual use, tubular body 3 is inserted inside sheath 11, which is gripped by the user at gripping member 13, and is drawn along so that projections 10 engage and are locked axially inside groove 15. Sheath 11 will be long and elastic enough for cap portion 14 to substantially contact and mold itself over lens 5.

The advantages of sheath 11 lie in the absence of a thickened portion caused by gluing, and the universal nature of cap portion 14 with respect to different types of lenses 5.

Moreover, sheath 11 is cheaper and easier to produce than known sheaths by comprising two as opposed to three component parts, and by involving no gluing.

Claims

1) A protective sheath (11) for a rigid or flexible endoscope (2), the sheath (11) comprising a tube (12) made of rigid or flexible material and having an open first end (12a) for insertion of one end of said rigid or flexible endoscope (2) ; and a window (14) located at a second end (12b) of said tube, and which is positioned, in use, over a view window (4) of said rigid or flexible endoscope (2) ; said sheath (11) being characterized in that said tube (12) and said window (14) are formed in one piece from transparent material.

2) A sheath as claimed in Claim 1, characterized in that said window is a cap portion (14) . 3) A sheath as claimed in Claim 1 or 2, characterized in that said material is selected from the group comprising: silicone rubber, polyurethane rubber, butadiene-styrene rubber, styrene-ethylene rubber, PVC, polyurethane, polyethylene, silicone, and mixtures of these.

4) A sheath as claimed in Claim 1 or 2, characterized in that said silicone material is Elastosil®.

5) A sheath as claimed in any one of the foregoing Claims, characterized in that said tube (12) and said window (14) are the same thickness.

6) A sheath as claimed in any one of the foregoing Claims, characterized by comprising an annular gripping member (13) fitted to said first end (12a) of the tube (12) .

7) An endoscopic device (1) comprising a rigid or flexible endoscope (2) having, at a first end (3a), a view window (4) with a lens (5) ; said device (1) being characterized by comprising a sheath (11) as claimed in one of the foregoing Claims.

8) A device as claimed in Claim 7, characterized in that said window (14) of said sheath (11) molds itself, in use, over said lens (5) .