DEVICE FOR USE IN TYING KNOTS

Abstract: A thread guide device (2) is provided which is adapted to be removably or fixedly mounted on the distal end of an endoscope (1), or which is an integral part thereof. The device (2) has a pair of thread guides (3), for example in the form of longitudinally extending passages, which, when the device (2) is mounted on the endoscope (1), are laterally spaced from one another. The device (2) permits a knot (8) formed by threads (6) which have passed through the thread guides (3) to be viewed by the endoscope (1).

Description: DEVICE FOR USE IN TYING KNOTS This invention relates to a device for use in tying knots. It is particularly intended for use in tying knots in surgery, and more particularly in surgery carried out using an endoscope, notably a flexible endoscope, and use in endoscopy is particularly described below. It can, however, also be used in fields other than flexible endoscopy, for example in laparoscopy, in which case, rather than being disposed on the end of an endoscope it would be disposed on the end of a member, e.g. a rigid or flexible rod, which can be inserted down one of the channels formed for laparoscopic use. It has hitherto proved difficult to tie knots during flexible endoscopy. In effect, the surgeon is operating down a single longitudinally extending channel, and in endeavouring to tie a knot the surgeon encounters the problem that an effective knot generally requires the application of a force along a direction transverse to the channel of the endoscope. The present invention aims to provide a solution to that problem. According to the present invention there is provided a thread guide device which is adapted to be disposed on the distal end of an insertion member, for example an endoscope, the device having a pair of thread guide means which, when the device is disposed on the insertion member, are laterally spaced from one another. Where the insertion member is an endoscope, the device permits a knot formed by threads which have passed through the thread guide means to be viewed by the endoscope. The invention further provides an endoscope having a thread guide device as aforesaid mounted on the distal end thereof. The invention also provides an endoscope having a pair of laterally spaced thread guide means at the distal end thereof. In the accompanying diagrammatic drawings: Figure 1 is a perspective view of a thread guide device according to the invention mounted on the distal end of an endoscope; Figure 2 shows the device and endoscope of Figure 1, being used to tie a half hitch knot; and Figure 3 shows the device and endoscope of Figure 1 being used to tie a self-lock slipknot. Figure 1 shows an endoscope 1 having a thread guide device 2 mounted on the distal end thereof. The endoscope itself can be conventional, and the type illustrated has an image bundle 10, two illumination bundles 11, and two operating channels 12. It must be emphasised, however, that other forms of endoscope could be used instead. The device 2 takes the form of a short tube of circular cross-section, which surrounds the distal end portion of the endoscope 1. The device 2 may be mounted on the endoscope 1 either as a push fit, by providing the device 2 with an internal thread to engage the external thread provided on some conventional endoscopes, or in any other appropriate fashion. The device 2 has a pair of thread guide passages 3 which extend parallel to the longitudinal axis of the endoscope 1 and device 2 from one end of the device to the other. The passages are sufficiently large in cross- section to permit a thread of the type normally used in surgery to pass therethrough. As illustrated, the two passages 3 are preferably arranged substantially at 180° with respect to one another about the axis of the device 2, but though this is desirable from the point of view of enabling the maximum force to be exerted on the knot which is being tied, it is not essential. The way in which the arrangement shown in Figure 1 is used in practice can be seen from Figures 2 and 3. Figure 2 additionally shows part of a patient's tissue 4, including a U-shaped tissue portion 5 through which a thread 6 has been passed by the surgeon. It is desired to tie a knot 8 in the thread 6. At the start of the knot-tying procedure, the ends 7 of the thread 6 are outside the patient, generally emerging through the mouth or anus. Either before or after the thread guide device 2 is mounted on the endoscope l, a loose knot is tied outside the patient, using the ends 7, and each of the ends 7 is then passed through a respective one of the passages 3 in a direction from the distal end of the endoscope to the proximal end thereof. The endoscope with the thread guide device thereon is then introduced into the patient and moved towards the portion of tissues. As this is done the loose knot 8 slides along the thread ends until the distal end of the endoscope is adjacent the portion of tissue 5. The surgeon then pulls on the ends 7 in the direction of the arrows indicated thereon. This causes a force to be exerted on the loose knot 8 which has a lateral component and which therefore tends to tighten the knot. During this whole process the knot can be viewed through the viewing channel of the endoscope, since the knot is directly in front of the viewing channel of the endoscope, and the field of view is not in any way impaired by the thread guide device 2. The process just described serves to tie a single half hitch knot. It is common practice for a surgical knot to consist of more than one half hitch, say two or three, and this can be achieved using the arrangement shown in Figure 2 , with the endoscope 1 and thread guide device 2 being withdrawn from the patient and reinserted each time an additional half hitch is made. Figure 3 shows the use of the same arrangement as Figure 2, but to tie a self-lock slipknot 8a. Apart from the differences in the knots themselves, the procedure used is the same as that just described with reference to Figure 2 . The thread guide device shown in Figures 1 to 3 is a component which is distinct from the endoscope itself, and is removable therefrom. However, it would alternatively be possible to provide the distal end of an endoscope with a pair of thread guide means integral with, or permanently secured to, the endoscope.

Claims: CLAIMS : 1. A thread guide device which is adapted to be disposed on the distal end of an endoscope, the device having a pair of thread guide means which, when the device is disposed on the endoscope, are laterally spaced from one another, the* device permitting a knot formed by threads which have passed through the thread guide means to be viewed by the endoscope. 2. A device according to claim 1, wherein the thread guide means are so arranged that, when the device is disposed on an endoscope, they are diametrically opposed to one another on opposite sides of the endoscope. 3. A device according to claim 1 or 2, wherein the device is in the form of an annular member provided with the said thread guide means. 4. A device according to claim 3, wherein the said annular member is cylindrical. 5. A device according to claim 3 or 4 , wherein each of the said thread guide means is in the form of a passage extending through the annular member. 6. A device according to claim 5, wherein the said passages are parallel to one another and to the axis of rotational symmetry of the annular member. 7. An endoscope having a thread guide device according to any preceding claim mounted on the distal end thereof. 8. An endoscope according to claim 7, wherein the thread guide device is as claimed in any one of claims 3 to 6, and wherein the said annular member surrounds the distal end of the endoscope without impairing the field of view of the endoscope. 9. An -endoscope according to claim 7 or 8, wherein the thread guide device is removably mounted thereon. 10. An endoscope according to claim 7 or 8, wherein the thread guide device is fixedly mounted thereon. 11. An endoscope according to claim 7 or 8, wherein a thread guide device is an integral part thereof. 12. A thread guide device which is adapted to be mounted on the distal end of a surgical insertion member, the device having a pair of thread guide means which, when the device is disposed on the insertion member, are laterally spaced from one another.

Inventors: BROWN GEOFFREY JOHN, GONG FENG, MILLS TIMOTHY NOEL, SWAIN PAUL, BROWN, GEOFFREY, JOHN, GONG, FENG, MILLS, TIMOTHY, NOEL, SWAIN, PAUL
Applicants: BROWN GEOFFREY JOHN, GONG FENG, MILLS TIMOTHY NOEL, SWAIN PAUL, UNIV LONDON, UNIVERSITY COLLEGE LONDON
Application year: 1993
Main classification: A61B17
IPC codes: A61B17