Device for the Placing of a Partial Catheter in a Body Cavity

The invention concerns a device comprising an auxiliary catheter and a fastening element with a blocking device for the placing of a partial catheter in a body cavity.

The invention chiefly concerns an instrument for the placing of a partial catheter in the form of a spirally coiled metal wire in a urethra in men and especially in the part of the urethra that is located in the prostate. It will also be possible to apply the device according to the invention for the placing of partial catheters in other body cavities such as the oesphagus, the biliary passage, the intestine, or the trachea.

Equipment for the placing of partial catheters in e.g. the biliary passage is known. A considerable disadvantage in the equipment already known is that it does not comprise an independent device for securing the partial catheter during the placing procedure. A further disadvantage in the equipment already known is that the equipment ends where the partial catheter begins, so that a very flexible partial catheter and particularly a spirally coiled metal wire catheter is very unstable during the process of placing.

The purpose of the present invention is to eliminate these disadvantages.

This purpose is achieved in accordance with the invention by means of an instrument which is characteristic in that a flexible auxiliary catheter, preferably made of a plastic material, which is partly slotted at one end, is introduced into the partial catheter, and that the partial catheter is secured in its position in relation to the auxiliary catheter by means of a fastening element, preferably made of stainless steel, which is led through the auxiliary catheter up to the slotted part, where a spirally coiled part of the fastening element clutches in the auxiliary catheter as a consequence of the slotting of the auxiliary catheter.

The auxiliary catheter and the fastening element are adjusted to each other in such a way that the fastening element sticks out of the catheter at the opposite end from the slotting, whereby the auxiliary catheter and the fastening element can be manipulated in relation to each other by rotary movements or pulling/pushing movements.

If the interior of the fastening element is suitably shaped, a movement of the fastening element will imply that it is detached from the partial catheter, after which the auxiliary catheter together with the fastening element can be pulled out of the partial catheter and after that out of the urethra.

When the equipment is used in accordance with the invention for the placing of a spirally coiled metal wire catheter in the urethra in a man, the placing procedure is carried out mainly under local anesthesia of the urethra and under indirect visualization of the position of the partial catheter by means of ultra-sound or radioscopy. In the last-mentioned case the auxiliary catheter and the fastening element can be provided with one or more radiopaque markers.

In the following the invention will be described in greater detail with reference to the drawing, where

FIG. 1 shows a perspective picture of a preferred embodiment of a partial catheter.

FIG. 2 shows a perspective picture of a preferred embodiment of the auxiliary catheter.

FIG. 3 shows a perspective picture of a preferred embodiment of a blocking device for the fastening element in relation to the auxiliary catheter in the partial catheter.

FIG. 4 shows a perspective picture of a preferred embodiment of the fastening element.

FIG. 5 shows a perspective picture of all the assembled parts of a preferred embodiment of the device in accordance with the invention.

In the drawing 1 indicates a tapered end coil of a spirally coiled metal wire catheter 2, preferably made of stainless, acid-resisting steel with a coating of gold. 3 and 4 indicate rods bent radially to the centre of the catheter and connected by a longitudinal, preferably 20 mm long rod 5. The rods 3 and 4 are preferably shifted 180 degrees in relation to each other. 6 indicated final turns in the lower end of the spiral which forms an attachment number on the catheters 2. 7 and 8 indicate partial, longitudinal slots in the upper end of the auxiliary catheter, preferably made in such a way that the one slot 7 is seven mm long and more than 20 mm shorter than the other slot 8, and that the two slots 7 and 8 are shifted 180 degrees in relation to each other, whereby it becomes possible for the two rods 3 and 4 to slide down into the slots. When the upper rod 3 slides down to the bottom of a preferred embodiment of the slot 7, further introduction of the auxiliary catheter 9 into the partial catheter 2 is stopped. 10 indicates a conical form of the lower end of the auxiliary catheter 9. 11 shows a funnel in the form of a stepped truncated cone, where the external taper of the cone is the same as the taper of the internal wall of the conical form 10 of the lower end of the catheter 9. 12 shows a spirally coiled form of the upper end of the fastening element, preferably made of one continuous piece of stainless steel wire. The spirally coiled part 12 is preferably made as five counter-clockwise turns with an outer diameter allowing the spirally coiled part 12 to be moved freely backwards and forwards in the lumen of the auxiliary catheter. The turns of the spirally coiled part 12 have a pitch and a internal diameter enabling the spiral to be screwed up around the lower part of the longitudinal rod 5 of the partial catheter 2 by axial rotation of the fastening element 13. If the length of the auxiliary catheter 9 is adjusted to the length of the fastening element 13, a 900 degrees screwing movement in order to connect the spiral 12 and the rod 5 will imply that the rod 3 is drawn tightly to the bottom of the slot 7, where it is stopped, while at the same time the fastening element 13 sticks five mm out of the conical opening 10 of the auxiliary catheter 9. 14 indicates a disc-shaped handle preferably made of a plastic material cast around the lower end of the fastening element 13. After the mounting further rotation of the fastening element 13 is prevented by the funnel 11 being pressed partly into the interior of the conical part 10 of the auxiliary catheter 9, so that the disc-shaped handle 14 is blocked. The blocking is further secured by the fact that after the mounting much more than five mm of the funnel 11 protrudes from the conical part 10 of the auxiliary catheter 9, so that rotation of the handle is blocked.