WO1999043371A1

WO1999043371A1 - Device for producing foam in a syringe body

Info

Publication number: WO1999043371A1
Application number: PCT/FR1999/000320
Authority: WO
Inventors: Alain Monfreux
Original assignee: Alain Monfreux
Priority date: 1998-02-27
Filing date: 1999-02-12
Publication date: 1999-09-02
Also published as: AU2429599A; FR2775433A1

Abstract

The invention concerns a device characterised in that it comprises a liquid drawing tip (7) forming foam, said tip (7) comprising a connection (6) with a syringe body (2), a sampling end (11) adapted so that it can be placed in contact with the liquid for drawing it by suction by actuating the syringe plunger (3), and means (11) for causing the spontaneous formation of foam from the drawn liquid and the suction resulting from the actuating of the syringe plunger (3), comprising means for introducing gas in contact with the drawn liquid for forming the foam.

Description

1

DEVICE FOR PRODUCING FOAM IN A SYRINGE BODY

The invention relates to a device for the production, inside the body of a syringe, of a foam formed by gas bubbles in a surfactant liquid such as a composition intended for sclerotherapy comprising a surfactant sclerosing agent, this foam being intended to be administered parenterally for therapeutic and / or cosmetic purposes in the human or animal body. We know that the injection of a sclerosing agent in the form of a foam for sclerotherapy of spider veins or varicose veins has significant advantages (see "Sclerosing treatment of saphenous trunks and their large caliber collateral by the MUS method" A. MONFREUX, Phlébologie 1997, 50, n ° 3, 351-353). However, this technique requires the use of glass syringes in which the foam can be formed by sealing the syringe body after taking a dose of liquid and then pulling on the plunger, whereby air is introduced into the body. syringe at the contact between the glass plunger and the syringe body which is liquid tight but not perfectly airtight. A slight air leak can indeed be created between the plunger and the glass syringe body by manual action on the plunger.

This technique has several drawbacks: glass syringes pose hygiene problems and must be sterilized, and it is not possible to use disposable plastic syringes whose pistons are perfectly sealed; the formation of the foam requires manipulations and the acquisition of a certain turn of hand (force and speed of traction on the piston) to obtain a homogeneous foam in the syringe; the characteristics of the foam obtained depend on the hand of the practitioner, and the properties of the liquid and the syringe, and are therefore not optimized as a function of the subsequent therapeutic use of the foam. In particular, the foam is generally formed from relatively large bubbles and is not stable over time. However, it is often desirable, in particular in the case of sclerotherapy, to form a foam having bubbles as fine as 2 possible, and whose stability over time is as great as possible, so as to allow the maintenance of the foam in the vein area to be treated as long as possible.

The invention therefore aims to overcome these drawbacks by providing a device for producing a foam from a surfactant liquid in a syringe which can be either a disposable syringe or a glass syringe, simply and quickly, the foam having homogeneous characteristics, little dependent on the practitioner, and which can be optimized according to the therapeutic and / or cosmetic application envisaged. The invention aims more particularly to propose a device for obtaining a fine and stable foam in a syringe, and in particular a device suitable for sclerotherapy using a foam of sclerosing composition.

The invention further aims to provide such a device which is simple, inexpensive, which can be produced in disposable form, in particular in synthetic material, and packaged in sterile form.

To do this, the invention relates to a device for the production inside the body of a syringe of a foam consisting of gas bubbles in a surfactant liquid intended to be administered parenterally, characterized in that it comprises a liquid sampling nozzle with foam formation, this nozzle comprising:

means for connecting the nozzle to the body of a syringe,

- a sampling end adapted to be able to be placed in contact with the liquid and allow the liquid to be withdrawn under the effect of the suction resulting from the manual actuation of the syringe piston (in traction in the direction of its extraction out of the syringe body),

- Means, called foaming means, capable of causing the spontaneous formation of a foam from the withdrawn liquid and the suction resulting from the manual actuation of the piston of the syringe, these foaming means comprising means for introducing a gas in contact with the liquid withdrawn to form the foam.

Different embodiments can be envisaged for the foaming means. One can thus use any device allowing 3 make a foam from a surfactant liquid and gas under the effect of a suction. Throughout the present application, the term "gas" designates any gaseous phase. The gas used is suitable for being able to form a foam with the surfactant liquid. In most cases, atmospheric air can be used, but the invention is also applicable for obtaining a foam with other gases.

It should be noted that the foaming means must be compatible with the connection of the sampling nozzle to a syringe, and must be able to operate by suction of the liquid and gas under the effect of the vacuum resulting from a traction exerted. on the syringe plunger. Advantageously and according to the invention, the foaming means comprise at least one pad of fibrous and / or porous and / or microperforated material, permeable to the surfactant liquid and to the gas, and adapted to be able to be brought into contact with the withdrawn liquid and with a source of gas, and to deliver, under the effect of the manual actuation of the piston of the syringe, the foam which spontaneously forms on passing through the tampon, in a conduit or a cavity communicating with the interior of the body d a syringe connected to the sampling tip by the connection means.

The inventor has in fact found that a simple pad of fibrous and / or porous and / or microperforated material makes it possible to form a foam of excellent quality in the syringe. This pad is adapted to be permeable to liquid, to gas, and to the foam formed, and is arranged to be able to be crossed by the withdrawn liquid and by the gas.

Advantageously and according to the invention, such a tampon can be formed of cotton - in particular a wad of hydrophilic cotton wool - or of a block of porous solid material - in particular a hard or soft solid foam -.

The buffer is adapted to be able to be traversed by the liquid, the gas and the foam formed, and this at least under the effect of the suction resulting from the actuation of the piston of the syringe.

Depending on the nature of the surfactant liquid and the gas used, the number, nature and dimensioning of the buffer (s) may vary. To be permeable to liquid, gas and formed foam, each pad includes a plurality of through passages (channels, perforations, pores, interstitial spaces between fibers, etc.). Advantageously and according to the invention, at least part 4 of these through passages has, in cross section, dimensions substantially greater than a minimum dimension making it possible to obtain the formation of a foam. These dimensions are in particular greater than the minimum critical diameter of the gas bubbles which can be formed in a foam of the surfactant liquid. It is known, in fact, that the gaseous bubbles which can be formed in a foam of surfactant liquid cannot have a diameter less than a critical minimum diameter which depends on the characteristics of the liquid and of the gas, and in particular on the surface tension of the liquid. in the presence of gas. To allow the formation of foam when passing through the buffer, the latter must have through passages allowing gas bubbles to pass, and therefore having dimensions greater than a minimum dimension corresponding to this critical minimum diameter, and below which foam does not form. In addition, the dimensions and the number of through passages must be adapted to allow the suction of liquid and gas through the tampon under the effect of the vacuum resulting from the manual actuation of the syringe plunger.

In general, a single tampon, homogeneous in its nature and dimensions, is sufficient to obtain an appropriate foam.

However, in order to improve the quality of the foam formed, it is also possible to provide several successive pads, the first having large through passages to form a coarse foam (with large bubbles), the following (s) refining the foam (reducing the size of the bubbles) and therefore having through passages of smaller dimensions. The average dimension of the through passages decreases in the direction of flow of the composition during sampling, that is to say from the sampling end to said means for connecting the sampling nozzle. These different buffers can be stacked in contact with each other, or even be integral to form one and the same multilayer block, or on the contrary be separated from each other by at least one free space. For example, a first pad may be provided at the level of the sampling end - in particular to form this sampling end - and another, finer, in said connection means.

In an advantageous embodiment, and according to the invention, the sampling tip comprises a tube, one end of which is in communication with the body of the syringe by means of the connection means. 5

Advantageously and according to the invention, the foaming means comprise a pad associated with the end of the tube which is opposite to the connection means, to form said sampling end. The tampon thus itself forms the sampling end. The tube and the connection means are sealed, so that a pull on the piston has the effect of drawing liquid if one part of the pad is immersed in the liquid, while another emerges and is in contact with the gas. , for example ambient air, and / or form the foam and entrain it in the tube towards the syringe body.

Advantageously and according to the invention, the tampon is spongy and suitable for spontaneously withdrawing by soaking in the liquid and capillary action a predetermined quantity of liquid. The tampon then acts not only as a foaming means, but also as a means of withdrawing and dosing the liquid. To do this, the tampon is advantageously formed of a wad of hydrophilic cotton wool and / or of a spongy porous solid foam such as a sponge of synthetic material or of soft natural origin at least in the soaked state. .

The sponge pad swells with liquid when immersed in the liquid. Advantageously and according to the invention, the tampon is adapted to present, when dry, width dimensions smaller than those of a neck of a container of liquid (ampoule of injectable solution), so as to allow its introduction into such a container, and, when soaked with liquid, in width greater than those of a liquid container neck (ampoule of solution for injection) so as to prevent its untimely extraction from the container.

The sampling tip according to the invention can be provided with only this buffer forming the sampling end. As a variant, the sampling tip may comprise at least one other pad of fibrous and / or porous material, for example another pad incorporated in the connection means, in particular in a bottom cavity of a frustoconical female connection forming these means connection, or another buffer incorporated in a chamber disposed between a tubular sampling end and the connection means. Advantageously and according to the invention, in one embodiment of the invention, the sampling end piece includes a chamber interposed between the connection means and the sampling end, in communication with the connection means and the end of levy, and 6 containing at least one pad of fibrous and / or porous and / or microperforated material.

In an advantageous embodiment, and according to the invention, the means for connecting the sampling end piece comprise a cavity receiving the liquid withdrawn from the sampling end, and the foaming means comprise a gas inlet in the cavity. Advantageously and according to the invention, the cavity receives the liquid through an orifice opening into the cavity, and the cross section of the gas inlet is smaller than that of this orifice. Advantageously and according to the invention, the foaming means comprise at least one pad of fibrous and / or porous and / or microperforated material placed in the cavity.

Furthermore, advantageously and according to the invention, the sampling end is provided with a filter adapted to prevent the suction of solid impurities. The device according to the invention can be in the form only of the sampling tip, the container and the syringe being packaged and supplied separately. In this case, the device of the invention consists of the sampling tip. Thus, the invention relates to such a sampling tip. However, a device according to the invention can also advantageously comprise a container of liquid comprising a neck through which the sampling tip can be introduced, for example a self-breaking glass ampoule containing an injectable solution. As a variant or in combination, a device according to the invention may also advantageously comprise a syringe adapted to be able to be connected to the sampling tip.

The device according to the invention is advantageously in the form of a kit of different parts packaged together comprising on the one hand, a sampling tip provided with foaming means and which can be connected to a syringe body, and, on the other hand, a container containing the liquid used to form the foam in the syringe body and / or a syringe itself (body and plunger) made of glass or disposable. The device according to the invention is advantageously a complete device, in the form of a ready-to-use kit, for the parenteral administration of a foam consisting of gas bubbles in a 7 surfactant liquid.

In addition, advantageously and according to the invention, the device also comprises a needle, for the injection into the human or animal body, of the foam previously formed in the syringe body. This needle is provided with means for connection to the body of a syringe, in particular a frustoconical female connection. Advantageously and according to the invention, this needle comprises at least one solid element permeable to foam - in particular a pad of fibrous and / or porous and / or microperforated material - inserted in the connection means, and adapted to be able to be traversed by the foam before passing through the needle channel. Advantageously and according to the invention, the solid element is formed of a cotton pad -in particular of a wad of hydrophilic cotton batting-.

The invention is advantageously applicable for sclerotherapy. The device according to the invention is then characterized in that the liquid is a composition intended for sclerotherapy comprising a surfactant sclerosing agent. The device according to the invention is then a device intended for the administration by intravenous injection of a composition intended for sclerotherapy in the form of a foam.

The invention further relates to a device characterized in combination by all or some of the features mentioned above or below.

Other objects, characteristics and advantages of the invention will appear on reading the following description which refers to the appended figures in which:

FIG. 1 is a schematic view of a first embodiment of a device according to the invention,

FIG. 2 is a schematic view illustrating the device of FIG. 1 in use,

- Figure 3 is a schematic view in axial section of detail of the cje sampling tip of the device of Figure 1, - Figures 4a to 4e are schematic views in axial section illustrating respectively five successive stages of a method of use of a device according to a second embodiment of the invention,

- Figures 5, 6 and 7 are schematic sectional views 8 axial respectively illustrating three other embodiments of a device according to the invention,

- Figure 8 is a schematic view illustrating the device of Figure 1 in use for foam injection. FIGS. 9 and 10 are schematic views similar to FIGS. 1 and 2 showing another embodiment of a device according to the invention,

FIG. 11 is a schematic view showing the device of FIG. 9 during a foaming step in the syringe body,

- Figure 12 is a schematic view illustrating the device of Figure 9 in use for parenteral administration.

The device according to the invention shown in FIG. 1 comprises a syringe 1 for parenteral administration, in particular by intravenous route, of injectable therapeutic and / or cosmetic compositions. This syringe 1 can be a glass syringe or a disposable syringe made of synthetic material, comprising a body 2 of cylindrical syringe and a piston 3 sliding in the body 2 of syringe, and provided with an actuating end extending outside the syringe body. Throughout the text, the term "piston" designates the movable assembly in the body 2 of the syringe acting as pumping means with manual actuation. In the case of a disposable syringe, the plunger 3 is formed of a flexible seal and a plunger rod extending axially from the seal to the outside of the syringe body 2. In the case of a glass syringe, the piston 3 is formed by a glass cylinder sliding in the body 2 of the syringe. The syringe body 2 comprises a male frustoconical end connector 4 drilled axially (the top of the truncated cone being oriented axially towards the outside of the syringe body 2). This male connector 4 is adapted to allow the connection of an injection needle 5 provided with a female frustoconical connector 8 of conjugate shape. It should be noted that the shapes and dimensions of these tapered syringe and needle connections 4, 8 are standardized and known per se.

The device according to the invention further comprises a nozzle 7 for withdrawing liquid with foaming. In a first mode of 9 embodiment shown in FIGS. 1 to 3, the sampling nozzle 7 comprises a tapered female connector 6 adapted to be able to be connected to the male connector 4 of the syringe body 2, of conjugate shape, by forming a separable tight connection. This female connector 6 is extended by a rigid hollow tube 9 whose length is adapted as a function of the depth of a container 10 containing the liquid to be sampled. The tube 9 carries, at its end 12 opposite to the connector 6, a pad 11 formed of a flock of cotton wool cotton wool. The tube 9 is hollow and defines an internal longitudinal conduit 24, one end 22 of which opens into the female connector 6 and is in communication with the body 2 of the syringe 1 to which the endpiece 7 is connected.

The tampon 11 is fixed to the end 12 of the tube 9, for example by tight windings, in the manner of cotton swabs applied to the two ends of the ear cleaning sticks of the cotton swab type (registered mark). The tube 9 is preferably made of synthetic material. The end 12 of the tube 9 with which the pad 11 is associated is provided with a filter 13 preventing the rise of any impurities (in particular cotton) in the tube 9.

It should be noted that the pad 11 is arranged so as to extend beyond the end 12 of the tube 9 over a sufficient height, so that this pad 11 can be partially immersed in the liquid to be sampled, while the end 12 of the tube 9 remains above the horizontal level of the liquid (Figure 3). In this way, when a pull is exerted on the piston 3 of the syringe (tending to extract it from the body 2) after having connected the sampling nozzle 7 to the body 2 of the syringe, the buffer 11 being partially immersed in the liquid, a foam spontaneously forms inside the body 2 of the syringe from the liquid withdrawn from the container 10 and atmospheric air entering the tube 9 via the buffer 11 through its emerging part. The cotton swab 11 therefore has the function of causing the spontaneous formation of foam from the liquid and atmospheric air withdrawn by the suction resulting from the actuation of the piston 3 of the syringe. This foam is delivered at the outlet of the tampon 11 in the conduit 24 of the tube 9 communicating with the inside of the body 2 of the syringe 1 connected to the sampling nozzle 7 by means of the sealed connection means 4, 6.

In this first embodiment, advantageously and 10 according to the invention, the sampling nozzle 7 is in the general form of a cannula. The buffer 11 associated with the free end 12 of the tube 9 forms a sampling end of the sampling nozzle 7.

In general, this end pad 11 is sufficient to obtain a good quality foam. It should however be noted that, according to a variant of the invention, a second pad, similar to the end pad 11, can be incorporated in the female connector 6, interposed between the opening opening of the conduit 24 of the tube 9 in the female connector 6, and the free end of the male connector 4 of the syringe body 2. This second pad is preferably thinner than the first pad 11, and has the function of refining the foam.

Once the foam has formed inside the body 2 of the syringe, it suffices to dissociate the sampling nozzle 7 and to replace it with a needle 5 for the injection of the foam using the syringe 1 in the human or animal body (Figure 8). In the second embodiment shown in FIGS. 4a to 4e, the sampling nozzle 7 comprises, at the end of the tube 9, a pad 14 formed of a spongy porous material suitable for spontaneously sampling and dosing by soaking in the liquid and capillary action, a predetermined amount of liquid. Thus, the tampon 14 has, in this embodiment, a double function: on the one hand, it allows the withdrawal of a predetermined dose of liquid, on the other hand, it allows, as in the first embodiment described above, the spontaneous creation of the foam inside the body of the syringe. This pad 14 can be formed from a block of soft, porous solid foam with open cells, spongy, natural or synthetic, associated with the end 12 of the tube 9, for example by gluing and / or sinking of this end 12 of the tube 9 in the foam block 14.

Figures 4a to 4e show the process used to produce the foam in the syringe body 2 with a device according to this second embodiment of the invention. Initially, the tampon 14 is dry and has a width less than that of the neck 15 of the container 10, which, in the example shown, is a self-breaking ampoule of injectable composition. After having broken the ampoule 10 to open the neck 15, the sampling tip 7 can be introduced into the ampoule 10, the tampon 14 being dry and suitable for 1 1 being able to pass through the neck 15, and being immersed in the liquid. In this way, the pad 14 is soaked with liquid essentially by capillary action, no traction being exerted on the piston 3. If this is deemed useful, a slight traction can nevertheless be exerted on the piston to facilitate absorption of the liquid in the buffer 14. In doing so, the volume of the buffer 14 increases. In particular, its width increases to a value which is preferably greater than that of the neck 15, so that this tampon 14, once soaked, can no longer be inadvertently extracted from the container 10. Furthermore, in lifting the syringe 1, the tampon 14 can be emerged outside the liquid, a predetermined dose of liquid being withdrawn inside this cancellous tampon 14 (FIG. 4d). In the subsequent step (FIG. 4e), it suffices to exert traction on the plunger 3 of the syringe, which causes the admission of air through the pores of the spongy material of the tampon 14, and the formation of 'a foam inside the body 2 of the syringe. It should be noted that the ampoules 10 of commercial injectable solution have standardized dimensions, so that the dimensions of the tampon 14 can be adapted to those of these ampoules 10, in particular of their neck 15.

It should be noted that one can also use, as a variant, the first embodiment of FIGS. 1 to 3 according to the method shown in FIGS. 4a to 4e to form the foam in the body 2 of the syringe. The pad 11 is then immersed (formed of a wad of hydrophilic cotton wool) in the liquid in order to soak it with a dose of liquid by capillary action (without exerting traction on the piston), then the pad 11 is emerged. out of the liquid, then a pull is exerted on the piston 3 to introduce air passing through the pad 11 and forming the foam in the tube 9.

In the embodiment shown in FIG. 5, the sampling nozzle 7 consists of a female frustoconical connection 6 for connection to a body 2 of the syringe, and of a pad formed by a block of porous, soft or 16 foam 16 tough. The end of the female connector 6 is directly associated with the foam block 16, in particular by gluing and / or welding and / or sinking. In this embodiment, the sampling tip 7 therefore does not include a tube. It suffices to partially immerse the block of foam 16 which acts as the end of 12 sampling, and exerting traction on the piston 3 to form a foam inside the female connector 6 and in the body 2 of the syringe. As a variant, if the pad 16 is spongy, it is also possible to proceed as in the embodiment of FIGS. 4a to 4e by immersing the pad 16 in the liquid beforehand, and by exerting traction on the piston 3 only after having emerged the soaked tampon 16.

In the embodiment of Figure 6, the female connector 6 of the nozzle 7 is extended by a pad formed of a block of foam 17 cut at a point at least substantially in the extension of the taper of the female connector 6. A reinforcing tube 18 is provided extending from the female connector 6 with which it communicates inside the foam block 17 to facilitate assembly and consolidate it. This tube 18 may for example be formed by a portion of metal injection needle, or by a hollow tube made of synthetic material.

In the embodiment shown in Figure 7, and unlike the embodiments described above, the sampling end is not formed by a pad of fibrous and / or porous material. Indeed, in this embodiment, the free end 12 of the tube 9, preferably provided with an anti-impurity filter 13, itself constitutes the sampling end of the sampling nozzle 7 intended to be immersed in the liquid. The female frustoconical connector 6 of the sampling nozzle 7 is not strictly sealed and comprises at least one orifice 19 passing through the gas inlet disposed near the junction of the female connector 6 with the tube 9,. In the embodiment shown, a single orifice 19 is provided and is generally sufficient. If necessary, several orifices 19, preferably regularly distributed around the axis of the female connector 6, can be provided.

Preferably, this orifice 19 has an at least substantially convergent / divergent shape so as to create a Venturi effect. The orifice 19 opens into a cavity 20 of the female connector 6 containing a pad 21 of fibrous and / or porous material (fluff of hydrophilic cotton batting, soft or hard foam, etc.). This orifice 19 therefore constitutes an inlet for gas (atmospheric air) into the cavity 20, which receives the liquid through an orifice 22 of the tube 9 also opening into the cavity 20. The cross section of the orifice 19 is less than that 13 of the orifice 22 emerging from the tube 9, that is to say at the cross section of the conduit 24 of the tube 9. For example, the diameter of the conduit 24 of the tube 9 can be of the order of a millimeter while that of the cross section (smallest cross section) of the orifice 19 is of the order of a tenth of a millimeter, or even less, depending on the nature and density of the pad 21. When the free end is plunged 12 of the tube 9 in the surfactant liquid to be sampled, and that a pull is exerted on the piston 3 of the syringe, it is found that a foam forms inside the body 2 of the syringe. This foam is in fact formed in the buffer 21 and is delivered into the cavity 20 immediately opposite the open end of the male connector 4 of the syringe.

This embodiment also has the advantage of better protection of the buffer 21 incorporated in the female connector 6, against contamination by contact with foreign bodies after unpacking. In addition, the qualities of the foam formed can be adjusted, not only as a function of the characteristics of the pad 21 (fineness or density), but also as a function of the number of air intake orifice (s) 19, the dimensions given respectively to the sections of each air intake orifice 19 and of the tube 9, and to the shape of each air intake orifice 19.

In the embodiment shown in Figures 9 and 10, the sampling nozzle 7 comprises a chamber 25 interposed between the frustoconical female connector 6 and the sampling end 12. This chamber 25 contains at least one pad 26 of fibrous and / or porous and / or microperforated material (flock of hydrophilic cotton wool, block of solid foam, etc.).

The chamber 25 is extended axially opposite the female connector 6 by a tube 9 whose free end 12 forms the sampling end 12. This end is tapered male so as to act as a tapered male connector capable of receiving the connector female 8 of an administration needle 5. The chamber 25 is in communication with the female connector 6 and with the tube 9. It is preferably made of transparent synthetic material, and can be provided with graduations in the manner of a pipette.

To use this device, the sampling end 12 is immersed in the liquid contained in a container 10. The length of the tube 9 is adapted to the height of the container 10 to allow reaching the bottom of the 14 container 10. A syringe 1 is connected to the sampling nozzle 7 and traction is exerted on the piston 3. The liquid rises in the tube 9 and fills the chamber 25, the pad 26 soaking up the liquid. When it is found that the chamber 25 is full of liquid or when the level of the liquid in the chamber 25 reaches a desired predetermined height, the free end 12 of the liquid is removed, then traction is again exerted on the piston 3 , whereby air is admitted through the sampling end 12 into the tube 9, into the chamber 25, and through the pad 26, which causes the formation of a foam in the female connector 6 and in the syringe body 2 (FIG. 11). To administer the foam thus produced, the sampling nozzle 7 can be replaced by an injection needle 5, with or without a permeable solid element for refining the foam, as shown in FIG. 8 with reference to the first mode of production.

However, the embodiment of FIGS. 9 to 12 also makes it possible to connect a needle 5 to the end of the sampling nozzle 7, as shown in FIG. 12, so that the foam crosses the tampon 26 during administration, before passing through the needle 5. In fact, it can be seen that by going back through this same buffer 26, the foam is transformed, by refining, into a stable and homogeneous spumescent foam. In this embodiment, the pad 26 therefore acts on the one hand as a foaming means during sampling to form the foam in the body 2 of the syringe, and, on the other hand, as a means for refining the foam during parenteral administration.

This embodiment is particularly advantageous in that it minimizes the number of manipulations of the practitioner and is simple and inexpensive. In addition, here again, the pad 26 enclosed in a chamber 25 is well protected from contamination.

Furthermore, in a variant of the invention, the device comprises at least one pad formed of a microperforated solid material (filter, grid, plate, etc.). Indeed, instead of a cotton ball or other fibrous material fluff, and a block of foam or other porous material, one can also consider using any other microperforated material capable of forming foaming means . By microperforated material is meant any material comprising a plurality of through passages as mentioned above, capable of forming 15 and / or to refine a foam when it is traversed by the surfactant liquid and the gas and / or by a foam already formed. As examples of microperforated material, it is possible to use a filter, a membrane, a grid or a metal or plastic plate, provided with a plurality of submillimetric perforations, or a plurality of such juxtaposed elements.

In all embodiments, the sampling nozzle 7 according to the invention therefore comprises foaming means arranged outside the body 2 of the syringe 1, upstream of the end orifice of the connector 4 male of the syringe body 2 in the direction of the flow of the liquid from the outside towards the inside of the syringe body 2 when a pull is exerted on the piston 3.

As seen in FIG. 8, the device according to the invention can also incorporate a needle 5 for parenteral injection of the foam previously formed inside the body 2 of the syringe. This needle 5 is provided with a female connector 8 for its connection to the male connector 4 of the syringe body 2. The needle 5 further comprises a pad 23 of fibrous and / or porous material, and / or microperforated, permeable to foam, inserted in the female connector 8, so that this pad 23 is crossed by the foam leaving the body 2 syringe, before it passes through the channel of needle 5 proper. This pad 23 can be formed of cotton - in particular a flock of hydrophilic cotton wool - or any other fibrous and / or porous material (soft or hard foam ...) and / or microperforated. The dimensions of the pores and / or the density of the material forming this pad 23 are adapted to allow the passage of the foam without breaking it through the pad 23, but while refining it, that is to say by reducing the size of the foam gas bubbles.

There is thus surprisingly obtained, at the end of the needle 5, an extremely fine, dense and stable spumescent foam.

This is in particular the case when the liquid used is a sclerosing composition comprising a surfactant sclerosing agent, for example VEINOSCLEROL® marketed by the KREUSSLER PHARMA Laboratory, ROISSY, France, or AETOXYSCLEROL® marketed by the DEXO Laboratory, NANTERRE, France, or other . The invention is particularly applicable in the field of sclerotherapy and makes it possible to produce and inject 16 extremely simple, fast and inexpensive, with high reliability, a fine and stable foam of sclerosing composition by intravenous injection.

It should be noted that the device according to the invention can be made entirely of synthetic material (with the exception of needle 5) and be disposable and for single use (sampling tip 7 and / or syringe 1 and / or needle 5 and / or liquid container 10), or on the contrary be at least partially reusable. Thus, in the embodiment of Figures 4a to 4e, it is possible to provide that the container 10 contains more than a single dose of liquid, the assembly formed of the container 10 and the sampling tip 7 can be reused several times, with several different syringes, for several injections. Obviously, all precautions must be taken to preserve the sterility of the whole.

In addition, the device according to the invention can also incorporate or be used with a reusable glass syringe. Furthermore, the different embodiments and uses of the invention described above can be combined with one another.

The invention is also applicable with compositions other than sclerosing compositions, and more generally for the parenteral administration of any cosmetic and / or therapeutic composition in the form of a foam consisting of gas bubbles in a surfactant liquid.

Claims

17

1 / - Device for the production, inside the body (2) of a syringe (1), of a foam consisting of gas bubbles in a surfactant liquid intended to be administered parenterally, characterized in that it comprises a nozzle (7) for withdrawing liquid with foaming, this nozzle (7) comprising:

- means (6) for connecting the endpiece (7) to the body (2) of a syringe,

- one end (1 1, 14, 16, 17, 12) of sampling adapted to be able to be placed in contact with the liquid and allow the sampling of the liquid under the effect of the suction resulting from the manual actuation of the piston (3 ) syringe (1),

- means (11, 14, 16, 17, 21), called foaming means, capable of causing the spontaneous formation of a foam from the withdrawn liquid and from the suction resulting from the manual actuation of the piston (3 ) of the syringe (1), comprising means (11, 14, 16, 17, 19) for introducing a gas in contact with the liquid withdrawn to form the foam.

2 / - Device according to claim 1, characterized in that the foaming means comprise at least one pad (11, 14, 16, 17, 21, 26) of fibrous and / or porous and / or microperforated material, permeable to liquid surfactant and gas, and adapted to be able to be brought into contact with the withdrawn liquid and with a gas source (11, 14, 16, 17, 19) and to deliver, under the effect of manual actuation of the piston ( 3) from the syringe (1), the foam which spontaneously forms on passing through this tampon (11, 14, 16, 17, 21, 26), in a conduit (24) or a cavity (20, 25) communicating with the inside of the body (2) of a syringe (1) connected to the nozzle (7) for sampling by the means (6) of connection.

3 / - Device according to claim 2, characterized in that a pad (11, 21, 26) is formed of cotton -in particular of a wadding of cotton wool hydrophilic-. 4 / - Device according to one of claims 2 and 3, characterized in that a pad (14, 16, 17, 26) is formed of a block of porous solid material - in particular a hard or soft solid foam.

5 / - Device according to one of claims 1 to 4, characterized 18 in that the sampling end piece (7) comprises a tube (9, 18), one end of which is in communication with the body (2) of the syringe by means of the connection means (6).

6 / - Device according to claims 2 and 5, characterized in that the foaming means comprise a pad (1 1, 14, 17) associated with the end of the tube (9, 18) opposite the means (6) of connection , to form said sampling end.

It - Device according to one of claims 2 to 6, characterized in that the pad (14) is spongy and adapted to spontaneously withdraw by soaking in the liquid and capillarity a predetermined amount of liquid.

8 / - Device according to claim 7, characterized in that the pad (14) is adapted to present in dry width dimensions smaller than those of a neck (15) of a container (10) of liquid, so to allow its introduction into such a container (10), and, once soaked with liquid, in width dimensions greater than those of the neck (15) so as to prevent its untimely extraction from the container (10).

9 / - Device according to one of claims 1 to 8, characterized in that the nozzle (7) for sampling comprises a chamber (25) interposed between the means (6) for connection and the sampling end, in communication with the connecting means (6) and the sampling end, and containing at least one pad (26) of fibrous and / or porous and / or microperforated material.

10 / - Device according to one of claims 1 to 9, characterized in that it comprises a container (10) of liquid.

1 1 / - Device according to one of claims 1 to 10, characterized in that it comprises a syringe (1).

12 / - Device according to one of claims 1 to 1 1, characterized in that the means (6) for connection comprise a cavity (20) receiving the liquid withdrawn from the withdrawal end, and in that the foaming means comprise a gas inlet (19) in the cavity (20). 13 / - Device according to claim 12, characterized in that the cavity (20) receives the liquid through an orifice (22) opening into the cavity (20), and in that the cross section of the inlet (19) of gas is less than that of this orifice (22). 19

14 / - Device according to one of claims 12 and 13, characterized in that the foaming means comprise a pad (21) placed in the cavity (20).

15 / - Device according to one of claims 1 to 14, characterized in that the sampling end is provided with a filter (13) adapted to prevent the suction of solid impurities.

16 / - Device according to one of claims 1 to 15, characterized in that it is in the form of a kit of different parts packaged together comprising a sampling tip (7) and a syringe (1) and / or a container (10) of liquid.

17 / - Device according to one of claims 1 to 16, characterized in that it further comprises a needle (5) for injecting the foam provided with means (8) for connection to the body (2) of a syringe (1), and in that this needle (5) comprises at least one solid element (23) permeable to foam - in particular a pad (23) of fibrous and or porous material and or microperforated- inserted in the means (8 ) of connection and adapted to be able to be crossed by the foam before its passage in the channel of the needle (5).

18 / - Device according to claim 17, characterized in that the solid element (23) is formed of a cotton pad -in particular of a wad of hydrophilic cotton wool-.

19 / - Device according to one of claims 1 to 18, characterized in that the liquid is a composition intended for sclerotherapy comprising a surfactant sclerosing agent.