AN INSERTER
The present invention relates to an inserter for an intrauterine system, comprising a handle (3) having a longitudinal opening (8) at its first end, said opening (8) having a longitudinal axis parallel to the longitudinal axis of the inserter, a first end (8a) and a second end (8b), a movable slider (5) arranged in said longitudinal opening (8) and having a first end (5a) and a second end (5b), a plunger (2) attached to the handle (3) and having a longitudinal axis, and an insertion tube (6) having a first end, a second end and a longitudinal axis essentially parallel to the longitudinal axis of the plunger (2), the insertion tube (6) being, along said longitudinal axis, movably arranged around the plunger (2). The invention is characterised in that it further comprises a flange (4) arranged on the insertion tube (6) at its first end, and means for locking the slider (5) into a position showing the correct insertion depth for the intrauterine system, said means being adjustable with respect to the opening (8) of the handle.
The present invention is related to an inserter for positioning an intrauterine device or an intrauterine system in the uterus.
BACKGROUND OF THE INVENTIONVarious types of inserters have been developed for the positioning of mechanical and copper wire-containing intrauterine devices (IUDs) as well as of intrauterine systems having a drug containing cylinder (IUSs). In the following, IUD and IUS can be used interchangeably and when one is mentioned, it is to be understood that either of them can be used.
Most common inserters are constructed for introducing the device into the uterus in a contracted state. These inserters usually comprise an insertion tube having a relatively narrow diameter and a rounded, blunt end which will pass through the cervical canal easily and will not damage or injure the fundus upon contact therewith, and a plunger inside the insertion tube. Prior to insertion the device, whether an IUD or an IUS, is usually retracted into the insertion tube either by means of string(s) attached to the device and intended for the removal of the device from the uterus, or by pushing the device into the insertion tube by a plunger with inserters having a special window to adapt the device in the expanded shape (see for example GB 1 403 393). Then the insertion tube with the device therein is introduced through the cervical canal into the uterus. When the device is correctly positioned, it is released either by pushing the plunger towards the uterus or by holding the plunger steady and by retracting the insertion tube outwards. Once expulsed from the insertion tube within the uterine cavity, the device is supposed to resume its original expanded shape.
Simple rod-shaped inserters have been suggested for inserting relatively small or sufficiently flexible intrauterine devices in their original, expanded shape by using simple push-in technique. With these inserters the correct positioning and a secure attachment of an IUS or IUD on the inserter as well as a proper handling of the removal strings may be difficult. Therefore there is still need for an improved inserter.
European patent application EP1 691 740 relates to an inserter, with which the correct positioning and directional stiffness of the device in the inserter prior to and during insertion can be ensured, for instance, by shaping the forward end of the plunger such that the IUS assumes a specified constant configuration when drawn into the insertion tube. The IUS thus will not be twisted during insertion.
European patent EP 798 999 relates to an inserter, which allows the correct positioning of an IUS also in those cases in which the elongate member of a T-shaped device contains active material, which involves a diameter larger than that of an elongate member of a copper-wire IUD. The inserter comprises a plunger, a handle attached to the plunger, a string for the removal of the IUS, a cleft on the end of the handle to lock the string(s) in such a way that the IUS remains immobile in relation to the plunger, and an insertion tube around the plunger. The IUS is drawn into the insertion tube by pushing the tube over the device or by pulling on the removal threads where after the threads are manually locked in the cleft. The relative movement of the plunger and the protective tube is restricted by a stop member or stop members to ascertain that the correct configuration of the IUS is achieved. The stop members ensure that the front edge of the insertion tube is stopped in a configuration in which the hemispherical tips of the T-wings remain partly uncovered by the insertion tube but the wings nevertheless remain pressed against each other. These stop members are however fixed on the handle.
The inserters described in these documents overcome many of the problems encountered with the conventional inserters, but the string(s) still need to be handled and manually locked. Further, the inserters are designed primarily for the insertion of the conventional devices which are to be inserted in a compressed configuration. Therefore there is still need for an improved inserter, which can be used to insert in original expanded configuration intrauterine devices and systems having frames of various shapes.
OBJECT AND SUMMARY OF THE INVENTIONAn object of the invention is to provide a simple, easy to use inserter for the positioning of an intrauterine system in the uterus by solving at least partially at least some of the problems mentioned above. An object of the invention is particularly to provide an inserter having an improved system for securing the simple and correct positioning of the intrauterine system in the uterus.
A typical inserter for an intrauterine system according to the present invention, comprises
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- a handle having a longitudinal opening at its first end, said opening having a longitudinal axis parallel to the longitudinal axis of the inserter, a first end and a second end,
- a movable slider arranged in said longitudinal opening and having a first end and a second end,
- a plunger attached to the handle and having a longitudinal axis,
- an insertion tube having a first end, a second end and a longitudinal axis essentially parallel to the longitudinal axis of the plunger, the insertion tube being, along said longitudinal axis, movably arranged around the plunger,
- a flange arranged on the insertion tube at its first end.
The inserter is characterized in that it further comprises
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- means for locking the slider into a position showing the correct insertion depth for the intrauterine system, said means being adjustable with respect to the opening of the handle.
A typical inserter for an intrauterine system according to the present invention, comprises
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- a handle having a longitudinal opening at its first end, said opening having a longitudinal axis parallel to the longitudinal axis of the inserter, a first end and a second end,
- a movable slider arranged in said longitudinal opening and having a first end and a second end,
- a plunger attached to the handle and having a longitudinal axis,
- an insertion tube having a first end, a second end and a longitudinal axis essentially parallel to the longitudinal axis of the plunger, the insertion tube being, along said longitudinal axis, movably arranged around the plunger,
- a flange arranged on the insertion tube at its first end.
The inserter is characterized in that it further comprises
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- means for locking the slider into a position showing the correct insertion depth for the intrauterine system, said means being adjustable with respect to the opening of the handle.
The invention therefore provides an easy to use inserter, by which only few simple steps are needed to prepare for the insertion and to securely install and position an intrauterine system into the uterus.
The longitudinal opening on the handle can have be also quite narrow and does not need to be symmetrically positioned on the handle and with respect to the longitudinal axis
The inserter comprises a flange arranged on the insertion tube at its first end. The aim of this flange is to keep the intrauterine system in a correct position and to protect it prior to insertion. The flange also functions as part of the means regulating the movement of the insertion tube.
The inserter may further comprise means for holding and guiding the strings during the insertion so that no manual handling of said strings will be needed. The inserter may also comprise locking means for reversibly locking the strings to immobilize the intrauterine system in relation to the plunger, said locking means being controllable by the slider and/or by the insertion tube.
The inserter according to the invention is suitable for the positioning of intrauterine devices and intrauterine systems having different sizes and shapes. The inserter is especially suitable for installing intrauterine devices having a flexible frame with continuous curved shape, for example annular, circular, oval, spiral, toroidal, triangular, shield-like, almond-like, diamond-like, elliptical or polygonal shape.
In the present description and claims, by first ends are typically meant the ends that are closer to the uterus during the insertion of the intrauterine system. Second ends are the ends opposite to the first ends. Moreover, the terms IUS or IUD and removal strings are used when describing the preferred embodiment of the present invention, but these are not to be construed as limiting the claims.
A part of the handle comprises an opening having a first end and a second end and running in the longitudinal direction of the plunger. The handle also preferably has at its first end a channel in which the insertion tube can slide in the longitudinal direction.
The handle can have many shapes and is designed for easy handling of the inserter even by using only one hand. The plunger attached to the handle is advantageously hollow or has a groove or bore running in the axial direction thus allowing the string(s) to slide freely in it, without any risk of them getting jammed between the plunger and the insertion tube. To enable the optimal and secure positioning of the intrauterine system in the inserter the forward end of said plunger is shaped to the form of a a slot or an extension to adapt the reservoir of the intrauterine system. Thus the IUS will not drop or be twisted during insertion procedure and assumes a specified constant configuration when released.
The forward part (part directed towards the uterus) of the inserter is preferably made of a flexible material to avoid perforation of the uterus, and can be straight or curved so as to conform to the anatomy of the uterus. The first end of the insertion tube comprises a flange and both are made of a relatively flexible material, but are preferably stiffer than the plunger.
The slider mechanism is preferably inside the handle and comprises at least one elongated element, which can be moved in the longitudinal direction of the insertion tube. According to an embodiment of the invention the slider comprises a means to move the slider, which preferably is a part of the slider. According to another embodiment of the invention the slider comprises at least two elements, preferably parallel, which are combined on at least one point by a transversal member. The transversal member may form means, for example a knob or switch, by which the slider can be moved. The handle can comprise one or more means to adapt the slider elements and to facilitate the movement of the slider, for example a support, a shoulder, a holder, a saddle, a groove or a slot. The slider may also comprise at least one structural element, for example an extension, which is capable to generate the necessary operation of the possible locking means to keep the strings immobilized during storage or during preparatory steps before insertion and/or to release the string(s) when the slider is moved to the backward position.
To ensure the correct positioning of the intrauterine system in the uterus, the slider is adjusted to correspond to the depth at which intrauterine system will be inserted, said depth being beforehand determined by using a sound or a probe. The slider comprising said means for locking it, which means are adjustable with respect to the opening of the handle can be for example a self-locking button slider and movable in a stepwise way controlled for example by an indentation, a cogwheel or a rack and pinion mechanism positioned inside the handle. The outer side of the handle has clear depth markings to facilitate the adjustment of the slider.
The slider and/or the insertion tube may additionally comprise at least one structural element, for example an extension, which is capable to generate the necessary operation of the locking means to keep the strings immobilized during storage or during preparatory steps before insertion or to release the string(s) when the slider is moved to the backward position.
According to an embodiment of the invention relating to the kit comprising also an intrauterine system, a therapeutic component of the intrauterine system is connected to the frame in at least one point. Moreover, the intrauterine system can be connected to the inserter for example via at least one connection part. The connection part is preferably designed such that it enhances the retention of the device on the inserter prior and during the insertion of the device.
The connection part can be for example a hollow knob, adapted to receive a pin, one of these parts being arranged on the intrauterine system and the other on the inserter. Another option is to use a traditional ball joint. A person skilled in the art is readily able to find a suitable solution for this connection part.
Also in view of this, and according to an embodiment of the invention, the first end of the plunger comprises at least one connection slot for receiving the connection part of the intrauterine system. The first end of the plunger may also comprise two diagonally symmetrical connection slots for receiving the connection part of the intrauterine system. It is naturally possible that there are more than two connection slots, such as three, four, five or six slots. The connection part then preferably comprises suitable parts fitting to these connections slots.
According to another embodiment of the invention, the first end of the plunger comprises at least one frame slot for receiving the frame of the intrauterine system. The first end of the plunger may also comprise two diagonally symmetrical frame slots for receiving the frame of the intrauterine system. The number of frame slots can also be higher, such as three, four, five or six. The frame slots can be parallel to the longitudinal axis of the plunger or non-parallel to it. The frame slots can for example be straight or slightly curved with respect to the outer surface of the plunger, in order for allowing the frame to be released. The frame slots are preferably narrow enough to prevent the therapeutic component from slipping out and long enough to allow the movement of the therapeutic component and the stretching/compression of the frame during the insertion step. The plunger or at least the first end of the plunger is large enough for containing the therapeutic component. The frame slot(s) together with connection parts and the flange assure that the intrauterine system will be securely fitted and in the correct configuration during the insertion.
According to a further embodiment of the invention, the first end of the insertion tube comprises at least one frame slot for receiving the frame of the intrauterine system. The first end of the insertion tube may also comprise two diagonally symmetrical frame slots for receiving the frame of the intrauterine system. The number of frame slots can also be higher, such as three, four, five or six. The frame slots can be parallel to the longitudinal axis of the insertion tube or non-parallel to it. The frame slots can for example be straight or slightly curved with respect to the outer surface of the insertion tube, in order for allowing the frame to be released. The frame slots are preferably narrow enough to prevent the therapeutic component from slipping out and long enough to allow the movement of the therapeutic component and the stretching/compression of the frame.
The inserter according to the present invention may also comprise locking means for reversibly locking the intrauterine system in relation to the plunger, said locking means being controllable by the slider and/or the insertion tube. This means that the locking means can also be controlled by a part of the slider and/or of the insertion tube, such as an extension of either or both of them. The locking means is any arrangement which, induced by the movement of the slider, of the means to move the slider or of the insertion tube, can immobilize the removal string(s) to held IUS in stable position and again unlock the string(s) after insertion to release the IUS. Particularly, the invention relates to a locking means which comprises an object capable of reversibly preventing the movement of the string(s) by at least partly moving or pivoting from the original position, for example rotating around a shaft or an axle, and vertically or horizontally attached to the handle. The object may have several shapes and may be for example round or rod-shaped, wedge, polygonal or rectangular with rounded or sharp corners. The surface of the object preferably comprises one or more extensions having variable size and shape, for example a knob, a rib or a switch.
When the slider mechanism is pressed down and moved to adjust the correct insertion depth a part or an extension of the slider is pressed against at least one extension of the object thus changing its orientation enough relative to the original position to cause release of the string(s). As soon as the slider is released, the strings will lock again.
Preferably the object has a slot or pinhole through which the string(s) run. The locking means may also comprise at least one counterpart against which the string(s) are pressed by the object and thus reversibly immobilized in the locking position. The counterpart has a suitable shape adapted to fit at least some part of the surface of the object. An extension, or extensions of the object can be used to keep the object and the counterpart in a fixed configuration until the IUS is released. The counterpart preferably has a suitable design to keep the string(s) in proper direction, for example a slot or pinhole through which the string(s) run. Further, the object and said at least one counterpart have preferably a suitable length and diameter to fit inside the handle.
As an alternative or in addition to the locking means, the outer surface of the insertion tube or the handle can have means to hold the strings until the intrauterine system has been inserted.
According to one embodiment of the invention, the locking means thus comprises
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- a main part,
- a first extension of the main part having an abutment surface,
- a counterpart adapted to form a blocking together with the main part,
wherein the locking means is rotatably mounted on the inserter.
According to another embodiment of the invention the main part comprises an opening or a slot in a diagonal direction through essentially the whole diameter of the main part, adapted to receive at least one removal string of the intrauterine system.
According to yet another embodiment of the invention, the locking means comprises
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- a main part,
- a first extension of the main part having an abutment surface,
- a second extension of the main part having a wedge-like shape,
- a counterpart adapted to form a blocking together with the main part,
wherein the second extension is adapted to form a blocking together with the counterpart and the locking means is rotatably mounted on the handle of the inserter.
According to one embodiment of the invention, the main part has essentially the shape of a cylinder, or it is of triangular shape, or of any other suitable shape.
According to one embodiment of the invention the insertion tube comprises an extension adapted to abut on the abutment surface of the first extension of the main part of the locking means.
According to one other embodiment of the invention the locking means comprises a main part comprising a first extension and a second extension arranged, in their initial position, to be essentially in contact with each other to from a blocking, wherein a part of the slider, the insertion tube or a part of the insertion tube is arranged to protrude into the main part of the locking means so as to separate the first and second extensions from each other.
According to yet one other embodiment of the invention the locking means comprises
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- a first locking part and a second locking part movably mounted on the inserter and arranged, in their initial position, to be essentially in contact with each other to form a blocking, and
- a first protrusion and a second protrusion arranged on the inner surface of the outer insertion tube,
wherein the first and second protrusions are arranged to move the first and second locking parts when moving the outer insertion tube.
The locking means could also be welding, gluing, cutting, knot or adhesion. The strings could thus be for example attached to the body of the inserter by welding (for example by heating), gluing with glue or attaching with an adhesive agent (such as sticker). The insertion tube would then release the attachment when contacting the slider. Other options could be a knot or other mechanical hindrance, when the slot provided for the strings is larger in the releasing position. The insertion tube could also comprise a blade that cuts the strings away from the inserter.
It is obvious to a person skilled in the art that, in accordance with the above description, the locking means can be of any other kind than those specifically listed above as well as a combination thereof.
During the preparatory steps the string(s) are hold tightly or locked but they are released automatically, when the slider is moved for example to adjust the insertion depth or when the second end of the insertion tube meets the slider or when the inserter is drawn out after insertion in order to release the IUS. As compared to previous inserters there is no need to manually handle the removal strings during the preparatory steps and during insertion, which increases security and hygiene and eliminates the possibility of user-made mistakes. Moreover, during the insertion the plunger and the medical device are protected by the insertion tube up to the cervix, which also increases hygiene. The invention further relates to a kit comprising an intrauterine system and an inserter according to the present invention. The intrauterine system can be any intrauterine system known in the art. Any details and embodiments listed above naturally apply mutatis mutandis to the kit according to the invention.
The present invention also relates to a method for positioning an intrauterine system in a uterus of a patient, wherein the method uses an inserter according to the present invention. The method comprises the steps of
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- sounding the depth of the uterus to obtain the correct positioning depth,
- moving the slider mechanism towards the second end of the opening until its position corresponds to said positioning depth, as shown by the depth markings of the handle,
- introducing the inserter into the uterus of the patient until the flange on the insertion tube abuts the cervical opening,
- introducing the plunger with the intrauterine system further into the uterus until the insertion tube meets the slider while moving backwards away from the uterus, which shows that the intrauterine system is in its correct location,
- removing the inserter from the uterus of the patient.
An example of the method for positioning the intrauterine system is given hereafter. To insert the IUS only few steps are needed. To prepare for the insertion the sterile package is carefully opened. The IUS is in a correct configuration relative to the inserter and there is no need to align the intrauterine system or for example to rearrange or correct the frame. The IUS is positioned at the forward end of the plunger with the reservoir of the intrauterine system protected by the extension of the plunger and the frame locating outside the plunger in the expanded configuration, secured and protected by the flange. The removal string(s) attached to the intrauterine system are preferably immobilized by the locking means, by the means on the surface of the insertion tube, or by both, to keep the IUS at a steady and correct position until it is released in the uterus. The removal strings do however not necessarily need to be immobilized.
Prior to the insertion procedure the depth of the uterus is measured by sounding. The slider mechanism or the means to move the slider is moved to correspond to the correct sounding depth. In the simplest form the slider is equipped with a self-locking press down and slide back button to adjust the correct sounding depth.
Then, the handle is hold tightly and the inserter is introduced into the uterus until the flange touches the cervical opening. At this point the insertion tube starts moving backwards and the flexible plunger with the intrauterine system will go forwards into the uterus. The insertion is continued until the insertion tube meets the slider, when also the removal string(s), if locked, are released by the locking means or by the means on the insertion tube. At this point IUS is in the correct location, as determined beforehand by using a sound as described above.
The inserter thus allows easy and secure positioning of an IUS. The use of the slider mechanism is straightforward and the locking means to hold the string(s) and the IUS immobile long enough as well as the predetermined distances the insertion tubes can be moved in each step guarantee an accurate positioning of the IUS during insertion and its accurate release.
DETAILED DESCRIPTION OF THE DRAWINGIn the following description, the term slider and the corresponding reference number are used to designate both the slider itself and the means to move the slider attached to the slider. The term slider is used for convenience of reading.
In this case the forward part of the handle 3 forms an opening 8, having the first end 8a and the second end 8b, which opening runs in the direction of the plunger 2 and has at the first end a channel 9 in which the insertion tube 6 slides in the longitudinal direction. The front surface of the means to move the slider 5a is set on the depth marking corresponding the depth of the uterus, i.e. the insertion depth, as determined before hand by using a sound or a probe.
Claims
1. An inserter for an intrauterine system comprising
- a handle (3) having a longitudinal opening (8) at its first end, said opening (8) having a longitudinal axis parallel to the longitudinal axis of the inserter, a first end (8a) and a second end (8b),
- a movable slider (5) arranged in said longitudinal opening (8) and having a first end (5a) and a second end (5b),
- a plunger (2) attached to the handle (3) and having a longitudinal axis,
- an insertion tube (6) having a first end, a second end and a longitudinal axis essentially parallel to the longitudinal axis of the plunger (2), the insertion tube being, along said longitudinal axis, movably arranged around the plunger (2),
- a flange (4) arranged on the insertion tube (6) at its first end, characterized in that the inserter further comprises
- means for locking the slider (5) into a position showing the correct insertion depth for the intrauterine system, said means being adjustable with respect to the opening (8) of the handle.
2. An inserter according to claim 1, characterised in that the flange (4) is arranged to at least partially protect the intrauterine system before its insertion.
3. An inserter according to claim 1, characterised in that the means for locking the slider (5) comprises a self-locking button movable in a stepwise way.
4. An inserter according to claim 1, characterised in that it further comprises means for holding and guiding the removal strings of the intrauterine system during its insertion.
5. A kit comprising an intrauterine system and an inserter according to claim 1.
Type: Application
Filed: Sep 11, 2009
Publication Date: Jul 14, 2011
Inventors: Heikki Lyyikäinen (Naantaki), Iikka Jutila (Raadelmaantie), Calvo Alonson (Piispanristi), Harri Jukarainen (Vadelmakatu), Taina Tjäder (Littoinen), Andrew Macleod (Cambridgeshire), Michael Noble (London Greater), David Whitaker (London Greater)
Application Number: 13/119,399
International Classification: A61M 31/00 (20060101);