WO1998047422A2

WO1998047422A2 - Flexible oesophagoscope

Info

Publication number: WO1998047422A2
Application number: PCT/ZW1998/000005
Authority: WO
Inventors: Barry David Brighton; Andries Petrus Pienaar
Original assignee: Barry David Brighton; Andries Petrus Pienaar
Priority date: 1997-04-21
Filing date: 1998-04-20
Publication date: 1998-10-29
Also published as: AU8415498A; WO1998047422A3

Abstract

An oesophagoscope (10) comprises a hollow tube (12) of a length at least equal to the length of a patient's oesophagus, the tube having a distal portion (12.1) which is flexible and a proximal portion (12.2) which is inflexible, wherein the flexibility of the distal portion is variable. The flexibility may be varied by means of an elongate member (26) attached to a distal portion of the oesophagoscope and operated (30) from a proximal portion thereof. The distal end of the oesophagoscope may further comprise means adapted to dilate the oesophagus of a patient.

Description

AN ENDOSCQPtC APPARATUS

FIE P QF THg I ENTIO

This invention relates to medical and veterinary instruments More

particularly, the invention relates to an endoscopic apparatus suitable for use in examining the oesophagus of a human or other vertebrate patient, for removing a foreign body therefrom and for performing operations thereon.

BACKGROUND TO THE INVENTION

The first case, of oesophagoscopy was reported in 1868 by Kussmaul

(Kussmaul, A- Zur Geschichte der Oesophigo und Gastroskopie. Arch Klin Med 1868;6:45β), who used a rigid urethroscope with a 13-mm diameter to examine the oesophagus of a sword-swal lower It was not until the early part of the 20th century, however, that Chevalier Jackson (Jackson, C. Tracheobronchoscopy, esophagoscopy and gastroscopy, St Louis, Mo

Laryngoscope Co, 1907-13) designed modern end-illuminated oesophagoscopes and pioneered the use in oesophageal foreign body removal, stricture dilatation, and the diagnosis of oesophageal disease The open tube (rigid) σesophagσscopes otolaryngologists use today are little changed from those of Jackson, except for the introduction in the 1960's of rigid telescopes with Hopkins glass rod lens systems for improved visualization of the oesophageal lumen (Ward pH. Birch G, Calcaterra TC Advances in endoscopic examination of the respiratory system Ann Otoi Rhino! Laryngol 1974,83 754-80) The fundamental technology allowing the development of fiberoptic oendoscopy appeared in 1928, when J L Baird

patented the first fiberoptic cables for the transmission of light (1928 British patent 285, 738) Lamm (Lamm H Biegsame optische Gerate Z Instrumentenkd 1930, 50 579-81) suggested the use of this new technology for gastroscopic examination in 1930 In 1963 Hirschowitz (Hirschαwitz, Bl. A fiberoptic flexible esophagoscope Lancet 1963,2.388) pioneered the first clinically functional flexible oesophagoscope with straight-ahead viewing, a fiberoptic light source, and channels for instrumentation and suction

The JESBERG-ROBERTS oesophagoscope combines the advantages of the traditional Jβsberg oesophagoscope with the extra wide oval tube construction of the ROBERTS modification The re-inforced smooth sledrunner distal tip ensures safe introduction without causing trauma However, this oesophagoscope comprises a rigid tube of which the distal end tends to exert great pressure on the oesophagus in the region of thoracic vertebrae numbers 6 to 11 , If the operator is not careful, the oesophagoscope can cause the oesophagus to be perforated or torn, which could result in death if action is not taken very rapidly using very expensive procedures

Another type of oesophagoscope is marketed by KARL STORZ. This device comprises a flexible solid scope comprising a first fibre optics cable for transmitting light to a lens at the distal end thereof; a second fibre optics cable for transmitting light reflected back from objects in front of the distal end, to an eye piece at the proximal end a fluid channel for air inflation of the oesophagus and for the irrigation of the distal end; and an instrument channel for conveying an instrument to the distal end, which instrument is operable from the proximal end of the oesophagoscope.

This type of oesophagoscope has many advantages over the JESBERG- ROBERTS type of apparatus However, it is still subject to serious disadvantages One of them is that, in a resting position, the walls of the oesophagus are relaxed, causing the oesophagus to fall flat with its forward wall lying on the rearward wall. The oesophagoscope, being of a somewhat small diameter, is capable of pushing the walls away from each other as it is introduced into the oesophagus from the mouth. However, with the walls of the oesophagus being relaxed, they tend to come up right against the lens at the distal end of the oesophagoscope, obstructing or limiting vision. Although the apparatus has a channel through which air can be pumped into the oesophagus as the oesophagoscope is introduced into it, the air can escape to the stomach with the result that vision remains insufficient.

Open tube oβsophagoscopy has been the workhorse for oesophageal examination by the otolaryngologist since Jackson's era. In contrast, since its inception in the 1960s, fiberoptic oendoscopy has largely been exploited by gastroeπterologists.

In the human body, the spinal column is curved backwards in the region of the thoracic vertebrae before forming a forward curve in the region of the lumber vertebrae. The oesophagus is located against the vertebrae and thus follows a correspondingly curved route before it enters the stomach.

When a bone or some other foreign object gets stuck in the upper reaches (or cervical portion) of the oesophagus, it can be removed without great difficulty, using conventional oesophagoscopes. However, when it gets stuck in the bottom third (or thoracic portion) of the oesophagus, it can create a life threatening condition. The conventional approach in removing such bones and foreign objects is to use an oesophagoscope, but because of the aforementioned curves in the oesophagus a serious danger exists that it may be perforated or torn during manipulations of the oesophagoscope by a surgeon, causing stomach fluids which are normally strongly acidic, to enter the cavity behind the heart and lungs of the patient This is a serious and potentially life threatening situation

According to Bacon, C K and Hendrix, R A Open Tube versus Flexible Esophagoscopy in Adult Head and Neck Oendoscopy, Ann Otoi Rhino! Laryngol 101-1992 147, the most dangerous of all oesophageal procedures is dilatation Dilatation of an oesophageal stricture with either endoscope significantly increases the chances of perforation. Blind dilatation, forceful dilatation, and dilatation through malignancies all increase the risk of perforation especially when done with open tube oesophagoscopes

There accordingly exists a need for an oesophagoscope which reduces the risk of perforation of the oesophagus of a patient when introduced thereinto, particularly in the lower thoracic portion thereof

SUMMARY OF THE INVENTION

According to the invention, there is provided an oesophagoscope comprising a hollow tube of a length at least equal to the length of a patient's oesophagus, the tube having a distal portion which is flexible and a proximal

portion which is inflexible, wherein the flexibility of the distal portion is variable.

In one embodiment of the invention, the distal portion conveniently comprises a plurality of segments flexibly connected to one another in end-to-end relationship. In this way, the segments could be flexibly connected to permit bending of the distal portion in a desired direction, preferably the anterior

direction.

The oesophagoscope may also comprise a hollow channel for passing instruments such as biopsy forceps, needles, double action jaws, a scalpel, or the like, through the channel to the distal end of the distal portion

In order to render the distal portion variably flexible, the oesophagoscope may comprise flexibility adjustment means adapted to influence the flexibility at the connections at which the segments are connected to one another. The flexibility adjustment means may conveniently be operable from the free end of the proximal portion

In an alternative embodiment of the invention the distal portion is of unitary flexible construction The oesophagoscope may comprise bending means capable of bending the distal portion m a desired direction, the bending means being operable from the free end of the proximal portion

The oesophagoscope in accordance with the invention may comprise an image transmitting means for transmitting an image from the distal end to the proximal end of the oesophagoscope Typically the transmitting means comprises a first fibre optics cable for transmitting light to the distal end of the distal portion, and a second fibre optics cable for transmitting back to an eye piece located at the free end of the proximal portion, light or images reflected from objects located ahead of the distal end of the distal portion thereby permitting a user to view said objects

In addition or as an alternative, the oesophagoscope in accordance with the invention may comprise a further tube for carrying irrigation water and/or air to the distal end of the distal portion The oesophagoscope in accordance with the invention may comprise dilating means adapted to cause the distal end of the distal portion to diiate.

The distal end of the distal portion may be provided with a tubular projection projecting longitudinally from the distal end of the distal portion, for dilating the oesophagus ahead of the distal end of the distal portion Conveniently, the diameter of the tubular projection is variable and the oesophagoscope in accordance with the invention may comprise means for causing the diameter of the tubular projection to be varied

Alternatively, the distal end of the oesophagoscope in accordance with the

invention is adapted to be dilated in such a way as to cause the diameter of the distal portion to be variable Generally the diameter of the distal portion can be increased so as to be capable of dilating the oesophagus

In order to prevent pinching of the oesophagus, the oesophagoscope in accordance with the invention may comprise a disposable or sterilisable sheath covering all movable portions and presenting a smooth outer surface.

For this reason, the sheath is preferably manufactured from a suitable plastic, rubber or other polymeric material having a high co-efficient of friction between its inner- surface and the outer surface of the distal portion, whilst having a low co-efficient of friction between its outer surface and the inner surface of the oesophagus

In order to cater for different ages of different patients, oesophagoscopes in accordance with the invention may be provided in different sizes having different diameters and different lengths.

In accordance with another aspect of the present invention, there is provided

- an oesophagoscope comprising a tubular projection at its distal end, of which the diameter is variable: and

- means for causing the diameter of the tubular projection to be varied.

BRIEF DESCRIPTION OF THE DRAWir fr

The invention will now be described by way of an example, with reference to the drawings in which;

- Figure 1 shows a side elevational view of an oesophagoscope in accordance with the invention;

Figure 2 shows a cross-sectional view of the oeseophagoscope of Figure 1 ; and

Figure 3 shows an oesophagoscope in accordance with the invention, in use.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to Figure 1 , there is shown an oesophagoscope 10 comprising a hollow tube 12 of a length at least equal to the length of a patient's oesophagus, the tube 12 having a distal portion 12.1 which is flexible and a proximate portion 12.2 which is inflexible The distal portion 12.1 is sub-divided into a plurality of short tube members 14. 16, 18, 20, 22 and 24 which are arranged in end-to-end relationship and held together by means of a cable 26 connected to the tube member 14 located at the distal end 28 of the distal portion 12.1. In order to vary the

5 flexibility of the distal end, the cable means could, for instance, comprise a plurality of cables (not shown), similar to the cable 26, threaded through suitable passages (not shown) provided in the tube members 14 to 24 such

that the distal portion 12.1 of the tube 12 can be bent in any desired direction by simply increasing the tension in the corresponding cable for that direction

I0 located on that side of the tube and releasing the tension on the cable for the opposite direction located on the opposite side of the tube 12. The tension of the cable 26 may be variable by means of tensionmg means which may take the form of an adjustable screw 30.

15 A handle 32 is provided for manipulation of the oesophagoscope 10 by an operator, so that the distal end 28 of the distal portion 12.1 can be introduced into a patient's oesophagus via the patient's mouth, whereafter the flexibility of the distal portion 12, 1 may be decreased before it is introduced into the thoracic portion of the oesophagus by operating the tensioning means 30.

0 Referring to Figure 2, the oesophagoscope 10 is in the form of a hollow tube 12 accommodating a further tube or channel 34 for carrying an image transmitting means in the form of a pair of fibre optics cables, the first fibre optics cable 40 for transmitting light to the distal end 28 of the distal portion 12.1 and the second fibre optics cable 42 for transmitting back to an eye piece (not shown) locatable at the proximate portion 12 2, any images reflected from objects located ahead of the distal end 28 of the distal portion

12 1

A further hollow channel (not shown) may be provided inside the tube 12 of the oesophagoscope 10, so as to permit an instrument such as a biopsy forceps, a needle, a set of double action jaws, a scalpel or the like to be passed therethrough to the distal end of the distal portion

Similarly, a further channel may be provided for carrying irrigation water and/or air to the distal end of the distal portion.

Referring to Figure 3, there is shown an oesophagoscope 10 in accordance

with the invention, after it has been inserted into the oesophagus of a patient from above It will be noticed that, in the area of the thoracic vertebrae numbers 6 to 11 the spinal column of the patient curves towards the front, presenting a concave line Since the oesophagus is located against- the spinal column, it follows a similar route which is curved concavely. By being flexible, the distal end 12.1 of the tube 12 is adapted to follow the route of the oesophagus on its way to the stomach far better than is the case with conventional oesophagoscopes. In this way, perforations of the oesophagus can at least be reduced, if not eliminated altogether

Claims

1 An oesophagoscope comprising a hollow tube of a length at least equal to the length of a patient's oesophagus, the tube having a distal portion which is flexible and a proximal portion which is inflexible, wherein the flexibility of the distal portion is variable

2. An oesophagoscope as claimed in claim 1 , which comprises

flexibility adjustment means adapted to adjust the flexibility of the distal portion

3. An oesophagoscope as claimed in claim 2, in which the flexibility adjustment means comprises an elongate member extending along the length of a portion of the tube between the proximal portion and a distal region of the distal portion to permit the flexibility of the distal portion to be varied.

4 An oesophagoscope as claimed in claim 3, wherein the flexibility adjustment means is a cable attached to the distal portion and operable from the free end of the proximal portion by means of a cable extending and retracting device attached to the cable

5 An oesophagoscope as claimed in any one of the preceding claims, wherein the distal portion comprises a plurality of segments arranged in end-t╧â-end relationship to one another.

6 An oesophagoscope as claimed in claim 5, wherein the segments are arranged to facilitate bending of the distal portion in an anterior direction

7 An oesophagoscope as claimed in any one of claims 1 to 4, wherein the distal portion is of unitary flexible construction.

8. An oesophagoscope as claimed in any one of the preceding claims, which comprises bending means capable of bending the distal portion in a desired direction, the bending means being operable from the free end of the proximal portion

9 An oesophagoscope as claimed in claim 8, in which the bending means is included in the flexibility adjustment means.

10 An oesophagoscope as claimed in any one of the preceding claims which comprises an image transmitting means for transmitting an image from the distal end to the proximal end of the oesophagoscope

11 An oesophagoscope as claimed in claim 10, in which the image transmitting means comprises:

a first fibre optics cable for transmitting light to the distal end of the distal portion; and

a second fibre optics cable for transmitting images reflected from objects located ahead of the distal end of the distal portion back to an eye piece located at the free end of the proximal portion, thereby permitting a user to view said objects

12 An oesophagoscope as claimed in any one of the preceding claims, which comprises a further tube for carrying irrigation water and/or air to the distal end of the distal portion.

13 An oesophagoscope comprising a hollow tube of a length at least equal to the length of a patient's oesophagus, the tube having a distal portion which is flexible and a proximal portion which is inflexible, the oesophagoscope comprising dilating means adapted to cause the distal end of the distal portion to dilate

14. An oesophagoscope as claimed in claim 13, In which the distal end of the distal portion is provided with a tubular projection projecting axially from the distal end of the distal portion, for dilating the oesophagus ahead of the distal end of the distal portion.

15 An oesophagoscope as claimed in claim 14, in which the diameter of the tubular projection is variable.

16. An oesophagoscope as claimed in claim 15, which comprises means for causing the diameter of the tubular projection to be varied.

17 An oesophagoscope as claimed in claim 16, wherein the distal end of the oesophagoscope is adapted to be dilated in such a way as to cause the diameter of the distal portion to be variable.

18 An oesophagoscope as claimed in claim 17, wherein the diameter of the distal portion is incraasable so as to be capable of dilating the oesophagus.

19 An oesophagoscope as claimed in any one of the preceding claims which comprises a disposable sheath covering all movable portions and presenting a smooth outer surface.

20 An oesophagoscope as claimed in any one of claims 1 to 19, which comprises a sterilisable sheath covering all movable portions and presenting a smooth outer surface.

21 An oesophagoscope as claimed in claim 19 or claim 20, wherein the sheath is manufactured from a suitable material having a high co-efficient of friction between its inner surface and the outer surface of the oesophagoscope, whilst having a low co-efficient of friction between its outer

surface and the inner surface of the oesophagus.

22 An oesophagoscope as claimed in claim 21 , wherein the sheath is manufactured from a plastics, rubber, or other polymeric material

23. An oesophagoscope as claimed in any one of the preceding claims, which is provided in different sizes having different diameters and different lengths selected to suit a particular patient.

24 A method of treatment or diagnosis of the human animal body

comprising the steps of:

inserting an oesophagoscope as claimed in any one of the

preceding claims into the oesophagus of a patient; and

performing a medical procedure inside the patient by means of the oesophagoscope

25. A stiffening device for an oesophagoscope having at least a flexible distal portion the stiffening device including an elongate member arrangable to extend between a proximal portion and a distal region of the distal portion of the oesophagoscope to increase the stifness of the distal portion

26 A stiffening device for an oesophagoscope as claimed in claim 25, wherein the elongate member is located within a tube of the oesophagoscope and extends for at least a portion of the length of the tube.

27 A stiffening device for an oesophagoscope as claimed in claim 25 or claim 26, which is operable from a first end region corresponding to the proximal portion of the oesophagoscope by means of an extending and retracting device

28 A stiffening device for an oesophagoscope as claimed in any one of claims 25 to 27, in which the elongate member is provided with oesophagoscope attachment means remote to the first region so as to be attachable to oesophagoscope at the distal region of the distal end thereof.

29 A dilating device for an oesophagoscope having at least a flexible distal portion, the dilating device including dilating means adapted to cause the distal end of the distal portion to dilate

30 A dilating device for an oesophagoscope as claimed in claim 29, the dilating means including a tubular projection attachable to the distal portion of the oesophagoscope for projecting axially from the distal portion, for dilating the oesophagus ahead of a distal end of the distal portion.

31 A dilating device for an oesophagoscope as claimed in claim 30, in which the diameter of the tubular projection is variable.

32 A dilating device for an oesophagoscope as claimed in any one of claims 29 to 31 , including means for causing the diameter of the tubular projection to be varied

33 A dilating device for an oesophagoscope as claimed in claim 32, in which the means for causing the diameter of the tubular projection to be varied is included in the stiffening device as claimed in any one of claims 25

to 28

34. An oesophagoscope, substantially as hereinbefore described and illustrated

35. A method of treatment or diagnosis of the human animai body, substantially as hereinbefore described and illustrated.

36. A stiffening device for an oesophagoscope, substantially as hereinbefore described and illustrated.

37, A dilating device for an oesophagoscope, substantially as hereinbefore described and illustrated.

38. A new oesophagoscope, a new method of treatment or diagnosis of

the human animal body, a new stiffening device, or a new dilating device substantially as hereinbefore described.