GB2363334A

GB2363334A - An endoscope

Info

Publication number: GB2363334A
Application number: GB0014555A
Authority: GB
Inventors: Ismail Khan
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-06-14
Filing date: 2000-06-14
Publication date: 2001-12-19
Anticipated expiration: 2020-06-14
Also published as: GB2363334B; GB0014555D0

Abstract

An endoscope (1) has a shaft (17) having a first channel (10) for receiving a working tool and a second channel (4) for receiving a lens for observing the tool. The first channel portion (10) and second channel portion (4) enter the shaft (17) at separate locations so that the working tool and lens can be inserted into and removed from the shaft (17) independently of one another. Preferably, the distal end (3) of the shaft (17) is chamfered so that during operation of the endoscope (1) the working tool is in constant view of the lens.

Description

1 4 1 2363334 I An Endoscope The present invention relates to an endoscope

and in particular, but not exclusively, to a cystoscope.

Endoscopes are used to carry out a wide variety of surgical procedures, such as laparoscopy, urological and arthroscopy procedures. Cystoscopes are used to carry out urological procedures.

Known cystoscopes comprise a working tool and a lens located in a common channel having a single entry point through which the working tool and lens are inserted. A surgeon using a cystoscope can view the area in which surgery is being performed by means of the lens whilst simultaneously performing surgery using the working tool. The lens of the cystoscope requires constant irrigation for its operation. However, the location of a working tool in the same channel as the lens means that the passage of the working tool through the channel is often impeded, thus causing difficulty and delay in performing the surgery. The performance of the surgeon carrying out the surgical procedure is hindered as a result.

Furthermore, the location of the working tool and lens in a common channel having a single entry point means that the lens must be removed each time a change in working tool is required. This is a particularly time-consuming process.

The distal end, i.e. the end of the cystoscope from the surgeon, is profiled so that the inferior side of the cystoscope terminates at a considerable distance behind the superior side of the cystoscope. This profile results in the occurrence of a blind spot, so that the working tool is not directly in the field of view of the lens when it emerges from the

2 cystoscope. As a result time is wasted while the surgeon attempts to bring the tool into the field of view of the lens so that the operation being carried out is protracted.

Time is a crucial factor in surgical operations, particularly when a patient is under general anaesthetic, and unnecessary time-consuming processes should thus be avoided.

Some known cystoscopes have a deflector mechanism to control the position of the working tool so that the working tool is always in the field of view of the lens. The deflector mechanism is arranged at the distal end of the cystoscope and consists of a steel wire of approximately 1 cm in length that can be deflected from a position parallel to the longitudinal axis of the cystoscope to a position perpendicular to the longitudinal axis to enable the working tool to be deflected accordingly. Such deflector mechanisms can result in damage to the urethra when the cystoscope is withdrawn with the deflector mechanism in a deflected position.

An object of the present invention is to provide an endoscope in which the above disadvantages are overcome.

Claims

The invention provides an endoscope as claimed in Claims 1 and 14 and an endoscope assembly as claimed in Claim 16. In a preferred embodiment of the invention the endoscope, e.g. a cystoscope, has means for connection to an irrigation source and this means preferably comprises an irrigation port having a tap. The first and second channel portions are preferably arranged parallel to one another. The first channel portion preferably has a diameter which is less than the diameter of the second channel portion. The shaft preferably has a chamfered distal end. In a preferred embodiment the angle of the chamfer of the distal end to the central longitudinal axis of the endoscope is from 45 0 to 5 0 0 inclusive, and is preferably substantially 45 0. In an alternative preferred 3 embodiment the first and second channel portions are separated from one another along at least a portion of their length. An embodiment of the invention will now be described with reference to the accompanying drawings, in which, Fig. 1 is a side view of a cystoscope according to the invention; Fig. 2 is a longitudinal sectional view of part of the cystoscope of Fig. 1; Fig. 3 is an end view of part of the eystoscope of Fig. 1, and Fig. 4 is a diagrammatic view of the end of the cystoscope of Fig. 1. In Fig. 1 and Fig.2, a cystoscope 1 has a proximal end 2 and a distal end 3. A lens and irrigation channel portion 4 extends from the proximal end 2 to the distal end 3, a lens 5 being insertable into the channel portion 4 at the proximal end 2 and movable along the channel portion 4 to the distal end 3. An eye-piece 6 is provided at the proximal end 2 to enable a surgeon operating the cystoscope to see through the lens 5. A locking mechanism 7 (not shown in detail) is provided in the vicinity of the eyepiece 6 to enable the lens 5 to be locked in position in the channel portion 4. Means for connecting the channel portion 4 to an irrigation source, e.g. in the form of an irrigation port 8, is located in the vicinity of the proximal end 2. The volume and rate of flow of liquid entering the eystoscope 1 through the irrigation port 8 is controlled by means of a tap 9 on the irrigation port 8. A channel portion 10 for holding a working tool (not shown) enters the cystoscope at a point proximal to the irrigation port 8 on the opposite side of the cystoscope 1 to the irrigation port 8 and has a means 11 for opening and closing the channel portion 10. A bung 12 at the proximal end 1 Oa of the channel portion 10 prevents irrigation liquid from leaking through the proximal end 1 Oa of the channel portion 10. The cystoscope 1 4 has an increased diameter housing portion 13 in the region of the irrigation port 8 and point of entry of the channel portion 10. Therefore, this housing portion 13 should remain outside the patient while surgery is being performed. A substantially circular guard 14 of approximately 4cm diameter is arranged at the distal end 14a of the housing portion 13 to protect the patient from injury by the housing portion 13. Preferably, the distal side of the guard 14 is concave and the proximal side is convex (not shown). A grip 15 is arranged in the vicinity of the proximal end 2 to enable the surgeon to hold the cystoscope 1 conveniently. The channel portion 10 enters the cystoscope preferably at an angle of from 12 1 to 18 0, preferably about 15 ', to the longitudinal axis of the cystoscope I but lies parallel and inferior to the channel portion 4 after entry. If the angle of entry of the channel portion 10 is less than 12 ', the proximal end I Oa of the channel portion 10 will be too close to other parts of the cystoscope 1, such as the grip 15. On the other hand, if the angle of entry is greater than 18 '1, it will be very difficult to insert a working tool into the channel portion 10, since the angle of entry will introduce a relatively sharp bend into the channel portion 10. The diameter of the channel portion 10 is preferably less than the diameter of the channel portion 4, as shown in Fig.3, since additional space is required in the channel portion 4 to enable irrigation liquid to flow around the lens 5. The approximate diameters of the channel portion 4 and channel portion 10 are 4.7mm (14 French) and 2.7mm (8 French) respectively. A substantial part of both the channel portion 4 and channel portion 10 are held within a substantially oval-shaped protective sheath 16, thereby forming a shaft 17. The channel portions 4 and 10 are separated from one another by a dividing wall 18 along at least part of their length in the region of the proximal end 2 of the cystoscope 1. This dividing wall 18 guides the lens 5 and working tool in their appropriate channel portions and separates the lens 5 and working tool so that they can be removed from the shaft 17 independently of one another. The length over which the channel portions 4 and 8 are divided is preferably from 4 to 6cm. Diametrically-opposed indentations (not shown) are preferably present in the wall of the shaft 17 as a result of the different diameters of the channel portions 4 and 10. These indentations also serves to guide the lens and working tool so that they remain in their appropriate channels. Preferably, the maximum diameter of the sheath 16 is 7.4mm (22 French). This diameter is particularly advantageous, since it renders the cystoscope suitable for carrying out up to twenty-five standard endourological procedures of both the upper and lower urinary tracts, without being so large as to cause unnecessary discomfort or injury to the patient on whom the cystoscope is to be used. The diameter of the sheath 16 may be reduced if the working tool and/or lens to be used is/are reduced, for example, in paediatric applications. The channel portion 4 extends beyond the channel portion 10 at the distal end 3 of the cystoscope 1, and the distal end 3 is preferably chamfered. This ensures that the working tool (not shown) is in the field of view of the lens 5 as the working tool emerges from the channel portion 10. Fig. 4 shows a diagrammatic view of the distal end 3 of the eystoscope 1. An angle c( of chamfer of the distal end 3 to the central longitudinal axis A-A of the cystoscope 1 is preferably no less than 45 0 and not more than 50 0 to ensure that the working tool (not shown) always remains in the field of view of the lens 5. The lens used with the cystoscope described above is preferably a 3C lens, i.e. the surface of the lens tapers at an angle of substantially 301 around its edge, in the form of an optic fibre of approximately 4min diameter. In use, a lens 5 is inserted into the irrigation and lens channel portion 4 of the cystoscope 1 at the proximal end 2 and moved along until it reaches the distal end 3. The lens 5 is locked in position by means of the locking mechanism 7. If the lens 5 is incorrectly positioned in the channel portion 4, the locking mechanism 7 will not lock. The shaft 17 of the cystoscope 1 is inserted into the area in which surgery is to be 6 performed. The working tool channel portion 10 is opened using the means I I and a working tool (not shown), such as a diathermy probe, guide wire, forceps, needle or biopsy forceps, is passed into the channel portion 10. The means I I is closed to hold the working tool in position. A working part of the working tool (not shown) which is used to carry out the required surgical procedure, emerges at the distal end 3, so that the working part is in the field of view of the lens 5. Irrigation of the lens 5 is carried out by opening the irrigation tap 9 on the irrigation port 8 to release liquid into the lens and irrigation channel 4. There is sufficient space around the lens 5 in the channel portion 4 to allow the liquid to circulate freely around the lens 5, so that the lens 5 is irrigated effectively. The volume and/or rate of flow of the liquid released into the channel portion 4 is controlled using the irrigation tap 9. If a change of working tool is required, the means I I is opened and the working tool is withdrawn from the working channel portion 10 without removing the cystoscope I from the patient on whom surgery is being performed. A second working tool is inserted in the channel portion 10, so that the working part of the working tool emerges from the distal end 3 of the cystoscope I in the field of view of the lens 5. The lens 5 remains in the channel portion 4 and the cystoscope remains in situ during changeover of the working tool. Considerable time is saved by changing the working tool in situ. Since removal of the lens 5 to change the working tool is also unnecessary, further time will be saved during changeover of the working tool. The separation of the lens 5 and working tool channel portions 4 and 10 along at least a part of their length eases the passage of the working tool through the shaft 17. The chamfering of the distal end 3 reduces the risk of occurrence of a blind spot in the field of view of the lens 5, so that the surgeon using the cystoscope is not hindered by a limited view of the area on which surgery is being performed. Furthermore, a deflector mechanism is not required in the cystoscope of the present invention. This is particularly advantageous, since deflector mechanisms can cause considerable damage to the urethra and/or bladder neck during withdrawal of the eystoscope. It will be appreciated that variations of the embodiment described above will be possible. For example, the lens used could be a 01, 121, 25' or a 701 lens. Similarly, the maximum diameter of the sheath 16, the diameter of the working channel portion 10, the diameter of the lens and irrigation channel portion 4 and the angle of entry of the working tool may be varied according to the particular application of the cystoscope. For example, a working-channel portion 10 can have a diameter in the range 1.3mm3Amm (4 FrenchFrench) and the lens and irrigation channel portion 4 may have a diameter in the range 4.Omm-6.0mm (12 French- 18 French). Furthermore, the lens and irrigation channel portion 4 and the working channel portion 10 may be separated by a dividing wall 18 along their whole length. However, this makes it more difficult to clean the cystoscope after use and adds to the production costs of the cystoscope. If the channel portions 4 and 10 are separated from one another along their whole length, the distal end of the lens and irrigation channel portion 4 and the distal end of the working channel portion 10 should be flush with one another, the distal end of the channel portion 10 being arranged axially behind the distal end of the channel portion 4. Similarly, there may be no dividing wall separating the channel portions 4 and 10. It is also possible to provide a cystoscope in which the working tool and lens are located in a common channel in which a distal end of the common channel is chamfered so that the working tool always emerges from the distal end in the field of view of the lens. If the working channel portion 10 enters the shaft 17 at an angle such that the lumen of the channel portion 10 is reduced considerably, it may be necessary to remove material 8 from the inside wall of the channel portion 10 to ensure that a working tool may be passed along the channel. Although the embodiment described above relates specifically to a cystoscope, the invention relates to any endoscope, such as a laparoscope, arthroscope or hysteroscope. CLAIMS:

1. An endoscope comprising a shaft, having a first channel portion for receiving a working tool and a second channel portion for receiving a lens for observing the working tool, the first channel portion and the second channel portion entering the shaft at separate locations so that the working tool and lens can be inserted into and removed form the shaft independently of one another.

2. An endoscope as claimed in Claim 1, wherein the second channel portion has means for connection to an irrigation source.

3. An endoscope as claimed in Claim 2, wherein the connection means is an irrigation port having a tap.

4. An endoscope as claimed in any one of the preceding claims, wherein the first channel portion is provided with means for opening and closing thereof.

5. An endoscope as claimed in any one of the preceding claims, wherein the first and second channel portions are arranged parallel to one another in the shaft.

6. An endoscope as claimed in any one of the preceding claims, wherein the shaft has a chamfered distal end.

7. An endoscope as claimed in Claim 6, wherein the angle of chamfer of the distal end to the central longitudinal axis of the endoscope is from 45 0 to 5 0 0 inclusive.

8. An endoscope as claimed in Claim 7, wherein the angle of chamfer is substantially 45 0.

9. An endoscope as claimed in any one of the preceding claims, wherein the first and second channel portions are separated form one another along at least a portion of their length.

10. An endoscope as claimed in any one of the preceding claims, wherein the diameter of the first channel portion is less than the diameter of the second channel portion.

11. An endoscope as claimed in any one of the preceding claims, wherein the first and second channel portions are located in a common sheath.

12. An endoscope as claimed in Claim 11, wherein the sheath is substantially ovalshaped.

13. An endoscope as claimed in Claim 11 or 12, wherein the diameter or maximum diameter of the sheath does not exceed 7.4min.

14. An endoscope having a shaft for receiving a working tool and a lens, the shaft having a chamfered distal end, so that the working tool emerges from the shaft behind the lens, whereby the working tool is in constant view of the lens during operation of the endoscope.

15. An endoscope substantially as herein described with reference to any one of the accompanying drawings.

16. An endoscope assembly comprising an endoscope as claimed in any one of the preceding claims and having a working tool located in the first channel portion and a lens located in the second channel portion.

17. An endoscope assembly as claimed in Claim 16, wherein the working tool is a guide wire, forceps, a diathermy probe, a needle or a biopsy forceps.

11

18. An endoscope assembly as claimed in Claim 16 or 17, wherein the lens is an optic fibre.

19, An endoscope assembly as claimed in any one Claims 16 to 18, wherein the lens is a substantially 30 degree lens.

20. An endoscope assembly substantially as herein described with reference to any one of the embodiments shown in the accompanying drawings.

1 i..- Amended claims have been filed as follows 1 A eystoscope comprising a shaft having a first channel portion for receiving a 5 working tool and a second charmel portion for receiving a lens for observing the working tool, the first channel portion and the second channel portion entering the shaft at separate locations adjacent the proximal end of the cystoscope so that the working tool and lens can be inserted into and removed from the shaft independently of one another 10 characterised in that the first channel portion has an entry length adjacent the proximal end of the cystoscope that is inclined at an oblique angle to a straight exit length extending therefrom to the distal end of the eystoscope, in that the second channel has a straight entry length adjacent the proximal end of the eystoscope in line with a straight exit length at the distal end of the cystoscope, 15 and in that the inserted working tool can be manipulated without the need for a deflector mechanism 2. A cystoscope as claimed in Claim 1 wherein the second channel portion has means for connection to an irrigation source.

3. A cystoscope as claimed in Claim 2 wherein the connection means is an irrigation port having a tap, and wherein the first channel portion is provided with means for opening and closing thereof.

25) 4. A cystoscope as claimed in any one of the preceding Claims wherein the second channel portion and the straight exit length of the first channel portion are arranged parallel to one another in the shaft.

5. A eystoscope as claimed in any one of the preceding Claims wherein the shaft has 30 a chamfered distal end.

KI I ANZ/101:,,k: 1)12001 tb 6. A eystoscope as claimed in Claim 5 wherein the angle of chamfer of the distal end to the central longitudinal end of the cystoscope is from 45' to 50' inclusive.

7. A cystoscope as claimed in Claim 5 or Claim 6 wherein the angle of chamfer is substantially 45'.

8. A eystoscope as claimed in any one of the preceding Claims wherein the first and second channel portions are separated from one another along at least a portion of their length.

9. A eystoscope as claimed in any one of the preceding Claims wherein the diameter of the first channel portion is less than the diameter of the second channel portion.

10. A eystoscope as claimed in any one of the preceding Claims wherein the first and second channel portions are located in common sheath.

11. A cystoscope as claimed in Claim 10 wherein the sheath is substantially ovalshaped in cross-section.

20. A cystoscope assembly substantially as herein described with reference to and/or as illustrated in any one of the several figures of the accompanying drawings.

KI iANZI 10 1:,1: 912001

20 12. A eystoscope as claimed in Claim 10 or Claim 11 wherein the diameter or maximum diameter of the sheath does not exceed 7.4mm.

13. A cystoscope substantially as herein described with reference to and/or as illustrated in any one of the several figures of the accompanying drawings.

14. A cystoscope assembly comprising a cystoscope as claimed in any one of the preceding Claims and having a working tool located in the first channel portion and a lens located in the second channel portion.

KIIA.N2JlO):,,L: 912001 k 15. A cystoscope assembly as claimed in Claim 14 wherein the working tool can negotiate the entry length of the first channel and extend into and through the exit length of the first channel.

Z:

5 16 A cystoscope assembly as claimed in Claim 14 or Claim 15 wherein the working too] is removable and exchangeable for another.

I.T. A cystoscope assembly as claimed in any one of Claims 14 to 16 wherein the working tool is a guide wire, forceps, a diathermy probe, a needle or a biopsy forceps. 10 18. A cystoscope assembly as claimed in any one of Claims 14 to 17 wherein the lens comprises an optic fibre.

19. A cystoscope assembly as claimed in any one of Claims 14 to 18 wherein the lens 15 comprises a substantially 30' lens.