BLOCKING UNIT FOR A FALLOPIAN TUBE

Abstract: Blocking unit for blocking a Fallopian tube. In order to avoid local anaesthetic and difficulty when inserting such a blocking device into the Fallopian tube and, on the other hand, to ensure sufficient anchoring in the Fallopian tube, it is proposed, on the one hand, that the end of the blocking device should be widened and, on the other hand, that it should be such that said widening does not occur until after the insertion into the Fallopian tube. In other words, provision is made for retaining means, in which the widened end is accommodated in the reduced state, which retaining means are rendered inactive after insertion into the Fallopian tube. This can be achieved by, for exemple making these retaining means from a bioabsorbable material or an applicator.

Description: Blocking unit for a Fallopian tube The invention relates to a blocking unit according to the preamble of Claim 1. A blocking device of this type, which forms part of the unit, is known from European Patent Application 0,010,812. A problem when inserting such contraceptive devices is, on the one hand, that there must be sufficient safeguard that the device will be held in place in the Fallopian tube in all circumstances and, on the other hand, that the insertion is as simple as possible. In the case of the device according to the abovementioned European Patent Application the insertion is facilitated to some extent by the rounded shape of the free end, but this again, on the other hand, increases the risk of the blocking device coming away. Besides, it is necessary to administer (local) anaesthetic if the free end has considerably larger dimensions than the Fallopian tube, because the insertion can be very pain¬ ful. Due to the fact that the insertion of such blocking devices is not simple and that anaesthesia may be necessary, the use of such contraceptive devices is restricted to specialized centres. German Offenlegungsschrift 2,404,605 discloses a blocking device which consists of an elongated element whose free ends are each inserted into a Fallopian tube. This eliminates a number of problems as regards holding the device in place in the Fallopian tube, because when the blocking device is coming out of one Fallopian tube it will have to go further into the other Fallopian tube, which is counteracted by said other tube. However, it has been found that such a design does not give sufficient guarantee to permit the end to be made without a widened part. For that reason, this German Offenlegungsschrift 2,404,605 proposes making the ends widened, with all the above-described consequences which this entails with regard to fitting and positioning. The object of the present invention is to provide a blocking unit which does not have the abovementioned disadvantages. This object is achieved in the case of a blocking unit of the type described above by the characterizing measures of Claim 1. Providing the retaining means ensures that the free, widened end can have relatively small dimensions while it is being inserted into the Fallopian tube because of the presence of the retaining means. If the re- taining means are then taken away in some way which is known in the prior art, the free end can widen, for example through its own resilience, and become fixed in the Fallopian tube. Consequently, on the one hand, it is not necessary to administer an anaesthetic while, on the other hand, it is possible to widen the end fur¬ ther than according to the prior art, with the result that a more positive positioning of the free end is produced through engagement with the Fallopian tube. As already stated above, the retaining means can comprise all means known in the prior art, which can be operated externally by, for example, pulling on cords and other constructions. However, according to an advantageous embodiment of the invention, the retaining means comprise a bioabsorbable or biodegradable material, prefe¬ rably of such composition that they dissolve in body fluids, and more par- ticularly the fluids near the Fallopian tube, within a few hours of inser¬ tion. On the one hand, this means that a particularly simple construction will suffice while, on the other, there is total certainty that no harmful effect whatsoever can occur for the user. The widening of the free end and the release by the retaining means can be achieved by all means known in the prior art. A particularly simple embodiment comprises making the free end from a permanently elastic, foldable material. The free end is inserted, held by the retaining means in the folded position, into the Fallopian tube, and after the retaining means cease to be effective the material can unfold elastically. The retaining means can also comprise an applicator inside which the blocking device is disposed in the folded state. If said applicator is then placed in the Fallopian tube with the blocking device fitted therein, and the blocking device is subsequently released by moving the applicator out of the Fallopian tube, leaving the blocking device in place, optimum posi¬ tioning can be provided. The element to which the free end is attached can be of any type known in the prior art, but is preferably straight. In this case the element is slightly elastic, so that it adapts to the shape of the user's body. In another embodiment the retaining means preferably comprise cap-shaped parts. For easy insertion, these parts are provided with a round tip, so that provision is made for simple insertion into the Fallopian tube. It is endeavoured to make the free end relatively flexible and the part which faces more towards the uterus stiffer. For this purpose, the free end is made of a relatively thin material, while the part of the blocking device facing the uterus is made of a thicker material. This produces a construction which, on the one hand, is sufficiently stiff to remain in position and, on the other hand, causes no damage to the Fallopian tube. Optimum positioning of the blocking device can be obtained by making it double. Such a design consists of two blocking devices of the type described above, interconnected in line with each other. In the case of such a construction the various parts are preferably of hollow design, so that an open connection between the two Fallopian tubes exists, on the one hand, but there is no connection between the Fallopian tubes and the uterus, on the other. Consequently, pressure variations arising through an egg being released are absorbed by the opposite Fallopian tube. In order to facilitate the insertion and monitoring of the correct posi- tion of such a double design, the central part is provided with indicator means between the two blocking devices. In this way the person placing the double construction can feel whether the central part is actually lying in the centre between the two Fallopian tubes. These indicator means preferably comprise a thickened part. Such a thickened part will likewise be gripped by the adjacent tissue material, with the result that further positioning of the blocking device is pro¬ vided. However, it is also possible to design the blocking device individually for each Fallopian tube. In this case said blocking device, in addition to the widened free end, preferably consists of a free end which connects thereto and is widened in the other direction, and which should be situated in the uterine cavity. At least one of these widened free ends is prefera¬ bly funnel-shaped. An essentially cylindrical part can be present between the widened ends, which part serves for fixing in the Fallopian tube. The invention will be explained in greater detail below with reference to exemplary embodiments shown in the drawing, in which: Fig. 1 shows a first embodiment of the device according to the inven¬ tion, shown in cross-section, fitted in the Fallopian tubes; Fig. 2 shows a perspective view of the device according to Fig. 1, in which the retaining means to be used here are shown separated therefrom; Fig. 3 shows the device according to Fig. 2, with the retaining means fitted; Fig. 4 shows in perspective a further embodiment of the device according to the invention; Fig. 5 shows a further variant of the device according to Fig. 4; and Fig. 6 shows diagrammatically a device for inserting the device accord- ing to Fig. 5. In the figures a first double embodiment of the blocking device accord¬ ing to the invention is indicated in its entirety by 1. It consists of opposite elongated parts 2, which are connected by a central part 8 in which a thickened part is disposed. Free ends 3 connect to the elongated parts 2. The double embodiment is provided with a passage 12 extending over the full length. The free ends 3 have a substantially larger radius than the elongated part 2 and central part 8. The transition from this region with larger radius to the central part is conical. As can be seen from Fig. 1 , the wall thickness of the free ends 3 is considerably smaller than that of the elongated part 2 or the central part 8. The positioning of the blocking device 1 according to the invention relative to the Fallopian tubes 6 and uterus 7 can also be seen from Fig. 1. The free end 3, which is relatively wide and is made of thin flexible material, provides a seal between the device and the Fallopian tube. The elongated part 2 and the central part 8 provide fixing. Moreover, a further seal is provided through the isthmus gripping the elongated part, giving additional security in this way. Correct positioning can be checked by feeling for the presence of thickened part 9. Fig. 2 also shows caps 4, provided with a rounded end 5. Said caps are made of bioabsorbable material, i.e. a material which can be readily absorbed by the body fluids at the position of the uterus or Fallopian tube. The caps 4 have external dimensions corresponding approximately to the diameter of the central part 8. Inside the caps 4 there is a receptacle for accommodating the folded free ends 3. This is shown in Fig. 3. For this purpose, it is, of course, necessary that at least the free ends 3 are made of a readily folding, springy, elastic material. In general, the blocking device will be made of a plastic which behaves neutrally with respect to the body and has the above-described properties permanently. The above-described device functions as follows: The blocking device is supplied in the state shown in Fig. 3. A gynae¬ cologist or other expert then inserts the blocking device into the uterus 7 of the user and into the Fallopian tubes 6. The correct positioning can be checked by, inter alia, checking the position of thickened part 9. Inser¬ tion of the free ends 3 into the Fallopian tubes 6 is relatively simple, due to the small external diameter of caps 4. It is not necessary to admi¬ nister an anaesthetic in this case, because this operation causes little pain to the user. Immediately after the insertion, the bioabsorbable material of caps 4 is dissolved, so that the free ends unfold and provide a locking relative to the Fallopian tube or wall of the uterus. The bioabsorbable material is removed in a harmless manner, known in the prior art. Due to the soft nature of the end 3, the device can be removed easily if necessary, without causing damage to the tube. Fig. 4 shows a variant of an embodiment, in which a "half" blocking device is being used, i.e. a single blocking device, which is indicated by 20. It has been found that, with the combination of cap 4 and the outward springing free end, the fitting is so simple and locking in the Fallopian tube is so good that the added fixing of the position of the blocking device by interconnecting two such blocking devices is not always neces¬ sary. Loop 21 is present for removal of the device. Fig. 5 shows a further embodiment of the device according to the inven- tion. Like the embodiment shown in Fig. 4, this is a single blocking device. It is indicated in its entirety by 30 and comprises an essentially cylin¬ drical central part 31, a flared part 32 which is intended for placing in the Fallopian tube, and a flared part 33 which should be situated in the uterine cavity after insertion. Engagement means 34 are fitted on said flared part 33. They are used for the subsequent removal of the device if, for example, fertility has to be restored. The central part in this embodiment is of such cylindrical design that the sphincter muscle present in the Fallopian tube grips this smooth part 31 and fixes the device in this way. Further adhesion can be provided by making part 31 thinner, winding a thread around it and placing hydrogel on it, which causes intergrowth with the surrounding tissue. For detection of the device, for example by X-ray or ultra-sound scan, certain parts of the device shown in Fig. 5 can be of special design. For example, the ends can be provided with a ring which reacts to said detec¬ tion means. It is also possible to fit a spring or the like which facilitates the removal in a funnel shape of both parts 32 and 33. Such a spring can com¬ prise a memory metal, which becomes active at the temperature of the human body, in order to facilitate removal in a funnel shape. This is important in particular if the device is made of a weak material, such as a silicone material. Fig. 6 shows diagrammatically an aid for fitting the device shown in Fig. 5. It consists of an applicator 36 which is provided with a plunger 37 which is movable relative thereto. The applicator is provided with a stop 38. Device 30 is supplied folded in this applicator. The doctor then inserts the applicator into the Fallopian tube as far as the stop 38, so that a certain indication is obtained that the applicator 36 has been inserted to sufficient depth. Thereafter, plunger 37 is held in place and applicator 36 is moved back, as shown diagrammatically in Fig. 6b. The end position is shown in Fig. 6c, in the case of which the device is free. It can be seen from Fig. 6 that the device is inserted from the uterus side. However, it is also possible to insert the device according to the in¬ vention operatively from the side of the Fallopian tube through the abdomi- nal cavity. In such a case the device 30 has to be fitted in applicator 36 exactly the other way round. Although the invention has been described above with reference to pre¬ ferred embodiments, it must be understood that numerous modifications can be made thereto without going beyond the scope of the present application, as described in the appended claims. For example, the retaining means can comprise means which react to temperature or moisture. It is also possible to provide the device with means which influence fertility. For example, copper or a hormone-releasing material may be pre¬ sent.

Claims: Claims 1. Blocking unit, comprising a blocking device (20) for a Fallopian tube, having an elongated part (2) with at least a widened free end (3, 32), which end must be placed in the Fallopian tube (6), characterized in that during the fitting retaining means are present at the end (3), which retaining means limit the external dimensions of the free end of the elon¬ gated part and are fitted in such a way that they are removable. 2. Blocking unit according to Claim 1 , in which at least the free end (3, 32) is made of a permanently elastic, foldable material. 3. Blocking unit according to one of the preceding claims, in which the elongated part is provided with a second widened free end (33), which lies opposite the first widened free end (32) and must be placed in the working position in the uterus. 4. Unit according to Claim 3, in which an essentially cylindrical part (31) is provided between the widened ends. 5. Blocking unit according to one of the preceding claims, in which the retaining means comprise a bioabsorbable material. 6. Blocking unit according to one of the preceding claims, in which the element is essentially straight before its insertion. 7. Blocking unit according to one of the preceding claims, in which the retaining means are cap-shaped means (4) . 8. Blocking unit according to one of the preceding claims, in which the free end is made of a relatively thin material, and the part of the device which is to face the uterus is made of a relatively thick material. 9. Blocking unit according to one of the preceding claims, in conjunc¬ tion with Claim 3, in which the retaining means comprise an applicator (36) for accommodating the blocking device. 10. Blocking unit according to Claim 9, in which the applicator (36) is provided with stop means (38). 11. Blocking arrangement, comprising two blocking units according to one of Claims 1 - 10, disposed essentially in line with each other, and con¬ nected by a central part (8) .

Inventors: DOORSCHODT BENEDICT MARIE, DOORSCHODT, BENEDICT, MARIE
Applicants: DOORSCHODT BENEDICT MARIE, DOORSCHODT, BENEDICT, MARIE
Application year: 1995
Main classification: A61F6
IPC codes: A61F6