Device for introducing a blunt-tipped cannula under a patient's skin

Abstract

Device for introducing a cannula with a rounded tip under the skin of a patient. The invention relates to a device for introducing a cannula (20) with a rounded tip (20a) under the skin of a patient for the purpose of injecting a biocompatible product, comprising a central body (1) equipped with a groove (2) extending in a sagittal direction (s) and having a sharp distal tip (2a) projecting from a distal end (1a) of said body for perforating said skin, said groove being arranged to allow the cannula (20) to slide along it beyond said distal tip towards at least one treatment area located under said skin, and a safety member (3) relative to which the body (1) is mounted in relative mobility between two stable positions, respectively for safety and for use.said organ comprising a distal extension (4) in which the sharp distal point (2a) is fully disposed – respectively fully protruding – in the safety position – respectively in the operating position. Figure 1a,

Description

Title of the invention: Device for introducing a cannula with a rounded tip under the skin of a patient

[0001] The invention relates to a device for introducing a cannula with a rounded tip under the skin of a patient for the purpose of injecting a biocompatible product, as well as an injection kit comprising such a device and at least one injection cannula with a rounded tip.

[0002] It applies in particular to injections of a filler product, in particular based on hyaluronic acid, under the skin of at least one part of a patient's body, for example the face and / or neck of said patient, in order to temporarily eliminate the effects of skin aging considered unsightly, such as for example wrinkles and sagging of the skin, and / or to revitalize said skin by hydrating the layers of the epidermis.

[0003] It can also be applied to autograft injections of autologous organic products previously taken from the patient, such as platelet-rich plasma (PRP), for example for fibroblastic and collagen stimulation of the skin with a view to correcting the unsightly effects due to its aging, or even fat, for example to correct loss of volume of the skin due to trauma such as an accident or a surgical operation.

[0004] To perform such an intervention, the practitioner generally uses an injection cannula which has a rounded tip and at least one lateral injection orifice arranged near said rounded tip. Indeed, this type of cannula is particularly suitable for filler products, which are generally quite thick, and makes it possible to minimize trauma to the tissues and vessels of the deep layers of the skin, such as hematomas, bruises or edemas, as well as nerve trauma.

[0005] During the intervention, the practitioner begins by perforating, with a needle having a sharp distal tip, an area of ​​the skin located not far from an area to be treated, in order to provide access to said area to be treated.

[0006] To facilitate this intervention, and in particular the introduction of such a cannula under the patient's skin, document WO-2016 / 020617 describes a device comprising a central body equipped with a groove which extends in a sagittal direction and has a sharp distal tip projecting from a distal end of said body for the perforation of said skin, said groove being arranged to allow the cannula to slide thereon beyond said distal tip towards at least one area to be treated located under said skin.

[0007] This arrangement allows the practitioner to save time compared to conventional injection techniques, because he does not have to locate the hole formed by perforation, since the device used for said perforation remains positioned in said hole and access to the area to be treated is materialized by the gutter, which is easily located. As a result, the practitioner therefore does not need to resort to practices that are traumatic for the patient, such as pinching the skin of said patient several times to locate the hole, risking making it bleed.

[0008] Furthermore, the number of manipulations of the perforation device is limited, which significantly reduces the risks of accidental puncture for the practitioner.

[0009] In particular, to improve the protection of the practitioner and / or the patient against accidental punctures, this device may be provided with a removable cap arranged to be fitted onto the distal end of its central body, in order to completely cover the sharp point of the gutter when said device is not in use, said practitioner removing said cap to release said point when perforating the skin of said patient and replacing it afterwards.

[0010] This solution is not entirely satisfactory, in that the cap is completely detached from the device when it is removed, which increases the risk of said cap falling and / or losing it.

[0011] The invention aims to improve the prior art by proposing in particular a device to enable the practitioner to more easily and more quickly insert an injection cannula under the skin, and therefore inject a product, said device being arranged to improve protection against the risk of accidental puncture throughout the procedure, in particular from the extraction of said device from its sterile packaging bag until the disposal of said device, and during its use on the patient, while being easy for the practitioner to handle.

[0012] To this end, according to a first aspect, the invention proposes a device for introducing a cannula with a rounded tip under the skin of a patient for the purpose of injecting a biocompatible product, said device comprising a central body equipped with a groove which extends in a sagittal direction and has a sharp distal tip projecting from a distal end of said body for perforating said skin, said groove being arranged to allow the cannula to slide thereon beyond said distal tip towards at least one area to be treated located under said skin, said device further comprising a safety member with respect to which the body is mounted in relative mobility between two stable positions, respectively a safety position and a position of use, said member comprising a distal extension in which the sharp distal tip is fully arranged - respectively fully protruding - in the safety position - respectively in the use position.

[0013] According to a second aspect, the invention proposes a kit for injecting a biocompatible product, said kit comprising such an introduction device, as well as at least one injection cannula with a rounded tip, the gutter being arranged to allow said at least one cannula to slide on it beyond its distal tip towards at least one area to be treated located under the skin of a patient.

[0014] Other features and advantages of the invention will appear in the following description, given with reference to the appended figures, in which:

[0015] [Fig. la],

[0016] [Fig.lb]and

[0017] [Fig. 1c] each represent in top view a device for introducing a cannula according to an embodiment of the invention, respectively in disassembled configuration ([Fig. 1a]), in safety position ([Fig. 1b]) and in use position ([Fig. 1c]);

[0018] [Fig.2a] and

[0019] [Fig.2b] each represent, in section along a median sagittal plane, respectively the safety organ ([Fig.2a]) and the body carrying the gutter ([Fig.2b]) of the device of the previous figures;

[0020] [Fig.3a] and

[0021] [Fig.3b] each represent, in section along a median sagittal plane, the device formed by assembling the member and the body of figures 2a and 2b, respectively in the safety position ([Fig.3a]) and in the use position ([Fig.3b]);

[0022] [Fig.4] represents an injection cannula with a rounded tip usable with the device previous figures,

[0023] [Fig.4a] being an enlargement of [Fig.4] centered on the circled area Z.

[0024] In relation to these figures, a device is described below for introducing a cannula with a rounded tip under the skin of a patient for the purpose of injecting a biocompatible product, as well as an injection kit comprising such a device and at least one injection cannula with a rounded tip.

[0025] A method of injecting a biocompatible product into the context of an aesthetic procedure is also described, using a kit according to the invention.

[0026] The injection kit may also be used for injecting a biocompatible product as part of a medical or veterinary procedure, said product containing, for example, mainly an anesthetic. In particular, the injection kit may be a single-use medical device intended to be used by qualified personnel, in particular medical or paramedical personnel.

[0027] In the context of an aesthetic intervention, the product to be injected may be a filler product, for example based on hyaluronic acid, to temporarily correct the unsightly effects of skin aging. In particular, a product based on fluid hyaluronic acid may be used to smooth the skin in order to reduce wrinkles. Similarly, a product based on cross-linked hyaluronic acid, therefore thicker, may be used to restore volume to the skin and / or to stretch said skin, in order to counterbalance sagging due to a loss of elasticity of said skin and / or to correct an asymmetry, in the case where an area of ​​the skin shows greater sagging and / or loss of volume than its symmetrical area.

[0028] The product to be injected may also comprise an additive having anesthetic properties, for example based on lidocaine, in order to reduce the pain that the patient may feel during the injection, this pain being all the greater as said product is thick. The product to be injected may also comprise an additive having antioxidant properties, for example based on mannitol, as well as vitamins to revitalize the layers of the skin in the area to be treated.

[0029] The product to be injected may also be an autologous organic product previously taken from the patient, such as for example fat or platelet-rich plasma (PRP), for purely aesthetic purposes and / or to allow autograft injections, in particular to correct unsightly effects due to trauma such as an accident or a surgical operation.

[0030] The area to be treated may be located on the patient's face or neck, particularly on the parts of the face or neck most subject to unsightly effects of skin aging, such as wrinkles or sagging.

[0031] For example, the area to be treated may be located at the corner of the lips (subject to "bitterness folds"), at the outer corner of an eye (subject to "crow's feet" wrinkles), on a temple, on the forehead, and in particular at the level of the glabella (subject to "lion's wrinkles"), at the level of an orbital zone (where dark circles and / or bags may appear), the tear trough (located under an eye) of a cheekbone or a cheek (where sagging and / or loss of volume of the skin may be observed).

[0032] The area to be treated can also be located on other parts of the body particularly subject to such aging effects, such as the hands, but also the arms, thighs, buttocks, chest for women, particularly at the neckline, scalp, stomach, mucous membranes, or even feet.

[0033] Depending on the product to be injected and the desired aesthetic effect, the area to be treated can be located at various depths of the patient's skin. For example, for the correction of wrinkles, the area to be treated is generally located in a superficial layer of the skin, in particular the epidermis or the dermis. On the contrary, for the correction of sagging of the skin, a lack of volume, and a possible resulting asymmetry, the area to be treated is rather located in a deep layer of the skin, notably the hypodermis, or a more superficial, but intermediate layer.

[0034] In particular, the area to be treated may be located in the stratum granulosum, that is to say the last layer of nucleated cells of the epidermis. The area to be treated may also be located under the epidermis, in particular between the dermis and the bone, and more particularly between the deep dermis and the periosteum of the bone.

[0035] Before carrying out the intervention, the practitioner can determine the areas to be treated by a careful examination of the patient, in particular by means of suitable lighting, to identify any lack of volume and the asymmetries which may result from this, but also to identify the blood vessels which should be avoided so as not to cause trauma to the patient.

[0036] This examination includes local observations but also a global observation, particularly regarding the face, in order to correct unsightly effects in a harmonious way and thus guarantee a natural result for the patient. Once the areas to be treated have been identified, the practitioner can mark them using a hypoallergenic pencil.

[0037] Furthermore, to limit the risks of infection, the practitioner must obviously take hygiene measures, particularly before marking the areas to be treated. To do this, the practitioner can clean the skin to remove any impurities, particularly makeup, and apply an antiseptic solution to said skin.

[0038] For the injection of a product, the kit comprises at least one cannula 20 with a rounded tip 20a, said cannula having at least one injection orifice 21 which may in particular be arranged laterally near said rounded tip. In particular, the orifice 21 has a diameter of between 0.05 mm and 1 mm and is located approximately 2 mm from the rounded tip 20a.

[0039] As is known, the use of rounded-tip injection cannulas proves to be particularly advantageous in the context of a cosmetic procedure, in that they not only make it possible to avoid the sectioning of blood vessels and nerve trauma when they are introduced under the skin of a patient, and thus to limit trauma for said patient, but also to limit the risk of accidental puncture for the practitioner.

[0040] Depending on the product to be injected, the depth of the area to be treated and / or its location relative to the access hole, the dimensions of the cannula 20 may vary. In particular, the cannula 20 may have a reduced external caliber if the product is fluid and, on the contrary, a larger one if the product is thick. For example, the cannula 20 may have an external caliber of between 14G (14 gauges, which corresponds to a diameter of 2 mm) and 33G (0.2 mm), and in particular between 22G (0.7 mm) and 25G (0.5 mm).

[0041] The cannula 20 may also have a more or less significant internal caliber, notably chosen from four standard wall sizes: normal wall (for the English “regular wall”), thin wall (“thin wall” in English), extra-thin wall (“extra-thin wall” in English), ultra-thin wall (“ultra-thin wall” in English), said internal caliber notably having an influence on the pressure applied to the product during the injection.

[0042] Thus, with an ultra-thin wall, corresponding to an ultra-large internal caliber, the practitioner can inject a thick product without applying too much pressure to said product, which makes said injection easier and reduces pain for the patient. Furthermore, by applying less pressure, the molecules of the product are less subject to physical constraints and therefore less likely to be damaged.

[0043] Furthermore, the cannula 20 may have a variable length, depending on the depth and / or the location of the area to be treated with said cannula relative to the access hole. This length may in particular be between 13 mm and 110 mm, and more particularly between 25 mm and 90 mm.

[0044] The cannula 20 is advantageously flexible, in order to facilitate its guidance towards the area to be treated, then the positioning of its injection orifice 21 in said area to be treated. In particular, the flexibility of the cannula 20 is linked to the external caliber, and in particular to the ratio between said external caliber and the internal caliber, said flexibility being all the more important as said ratio, and therefore the thickness of the wall of the cannula 20, is reduced.

[0045] Furthermore, the cannula 20 may be at least partially made of stainless steel, in particular of SUS 304 alloy or of AISI 304 alloy (with crude chemical formula FeCri8Niio), the latter being particularly remarkable for its good performance in terms of flexibility, robustness, elasticity, resistance to corrosion and tolerance by the patient's body, and / or of a shape memory alloy.

[0046] In addition, the outer surface of the cannula 20 may have undergone a special treatment, for example based on silicone, in order to facilitate the sliding of said cannula under the patient's skin, and therefore to minimize trauma for said patient, in particular hematomas, bruises or edemas.

[0047] In a known manner, to inject the treatment product, the cannula 20 is mounted on a syringe or another type of container in which a quantity of said product is packaged.

[0048] To do this, the cannula 20 has a base 22 on which a proximal end 20b of said cannula opposite the rounded end 20a is mounted, for example by being fixed by means of an adhesive in a housing provided for this purpose on said base, said base being intended to be mounted on a tip of a syringe containing the product to be injected.

[0049] For example, the base 22 may be of the Luer-Lock® type, to be mounted respectively by screwing or by friction on the tip of the syringe, these types being advantageously universal to allow the use of the cannula 20 with all types of syringes or other containers. In particular, the base 22 comprises fins 25 to allow connection to the syringe-type container.

[0050] Furthermore, the base 20 may be made of a polymer material, for example polypropylene or a polypropylene copolymer, in particular ethylene-polypropylene. In general, the base 20 may be made of a non-flammable material, in particular pyrogen-free.

[0051] To enable the practitioner to quickly identify the external caliber and / or the internal caliber of the cannula 20, and thus select said cannula according to his needs, the base 22 of said cannula may comprise a marking identifying its external caliber and / or its internal caliber.

[0052] In particular, the identification marking consists of a coloring of the base 22, the coloring corresponding to the internal caliber and / or the external caliber of the cannula 20, as defined in particular by the standard NF EN ISO 6009.

[0053] In order to be able to introduce such a cannula 20 under the skin of a patient, the method provides a step of perforating an area of ​​said skin, in order to provide an access hole for the cannula 20 under said skin.

[0054] To do this, the injection kit comprises a device for introducing the cannula 20 under the patient's skin, said device comprising a central body 1 equipped with a gutter 2 which has a sharp distal tip 2a projecting from a distal end 1a of said body for perforating the skin.

[0055] In relation to the figures, the gutter 2 extends in a sagittal direction s, in particular contained in a median sagittal plane S which forms a plane of symmetry for the device, and in particular for the central body 1, the device being shown in section along said sagittal plane in figures 3a and 3b.

[0056] The gutter 2 further defines a transverse plane T which is perpendicular to the sagittal plane S and on which the gutter 2 extends to its distal tip 2a, in particular in a sagittal direction s defined at the intersection between the planes S, T, said transverse plane passing in particular in said distal tip, the device being represented in said transverse plane in figures 1a, 1b and 1c.

[0057] In particular, the length of the sharp distal tip 2a is limited to ensure penetration of said tip to a limited depth of the patient's skin, and thus avoid trauma to the tissues and vessels of the deep layers of the skin, such as hematomas, bruises or swelling, as well as nerve trauma.

[0058] The device further comprises a safety member 3 relative to which the body 1 is mounted in relative mobility between two stable positions, respectively a safety position (figures 1b, 3a) and a use position (figures 1c, 3b), said member comprising a distal extension 4 in which the tip 2a is entirely arranged - respectively entirely protruding - in the safety position - respectively in the use position.

[0059] This arrangement makes it possible to protect the practitioner against the risk of accidental puncture by the point 2a, in particular during handling of the device, but also the patient, in particular by allowing said practitioner to keep said point inside the safety member 3 until the very last moment before the perforation of the skin of said patient.

[0060] This arrangement also makes it possible to ensure optimal protection of the tip 2a during storage of the device, and in particular to avoid untimely release of said tip during said storage. Thus, the risk of accidental perforation by the tip 2a of an individual sterile package in which the device is packaged is limited, in order to guarantee the sterility of said device until its use.

[0061] In the embodiment shown, the distal extension 4 comprises a housing 5 which extends in the sagittal direction s and in which the body 1 is mounted to move in sagittal sliding.

[0062] Advantageously, the housing 5 has an internal geometry, in particular a frustoconical geometry, which is complementary to the external geometry of the body 1, in order to facilitate the sliding of said body in said housing.

[0063] In particular, in the embodiment shown, the distal extension 4 has a distal end 4a with which the distal end 1a of the body 1 is arranged to come into frontal alignment when the device is in the position of use, as shown in figures 1c and 3b.

[0064] The distal end 4a of the extension 4 has a blunt, and in particular rounded, shape, as well as a flared shape in the transverse plane T, in order to ensure non-traumatic contact of said distal end against said skin when the sharp point 2a is fully inserted into said skin, such contact also having the advantage of being psychologically reassuring for said patient.

[0065] Furthermore, as shown in figures 1a, 1b, 2a, 2b, 3a and 3b, the housing 5 comprises a bottom in which a sagittal groove 6 is formed, the body 1 comprising a lower part 1d on which a sagittal rail 7 is formed which is mounted in relative sliding in said groove.

[0066] Two stops, respectively distal 8a and proximal 8b, are formed on the lower part Id of the body 1, being aligned in the sagittal direction s, and in particular with the rail 7. Similarly, the groove 6 has a proximal lug 9 arranged to come to bear against the distal stop 8a ([Fig.3a]) - respectively proximal 8b ([Fig.3b]) - in the safety position - respectively in use.

[0067] In relation to figures 1a to 1c, the safety member 3 - respectively the body 1 - comprises two distal blades 10 - respectively proximal blades 11 - which extend laterally on either side respectively of said member and of said body while being symmetrical with respect to the sagittal direction s, and more particularly with respect to the sagittal plane S, a distal blade 10 being mounted in relative mobility with respect to an adjacent proximal blade 11 between a position separated from - respectively brought closer to - said proximal blade to allow the arrangement of said device in a stable safety position - respectively of use.

[0068] The blades 10, 11 are formed in a single piece with the safety member 3 or the body 1, in particular by molding a plastic material, and each have a thickness that is sufficiently thin to give them elastic deformation properties, in order to allow their relative movement between the stable positions of the device.

[0069] In particular, one of the distal blades 10 and the proximal blades 11 each comprises a free end provided with a pivot 12 which is rotatably mounted in a complementary ball joint formed on respectively a free end of the other of the proximal blades 11 and the distal blades 10, in order to allow the relative movement of the body 1 with respect to the safety member 3 by rotation of said pivots in said ball joints.

[0070] In the embodiment shown, the pivots 12 are formed on the free ends of the proximal blades 11, and the ball joints 13 on the free ends of the distal blades 10. Alternatively, the pivots 12 may be formed on the distal blades 10 and the ball joints 13 on the proximal blades 11.

[0071] To move the device from the safety position to the use position, for example after removing it from its sterile packaging, the practitioner can pinch said device between his fingers, for example by placing two of his fingers on respectively a front face of a distal blade and a third finger on a proximal wall 1b of the body 1, or by pinching each pair of blades 10, 11 opposite each other with respectively one of his hands, in order to move the body 1 towards the member 3 so as to disengage the lug 9 from the proximal stop 8b, and this until said lug engages in the distal stop 8a, in order to lock the device in the use position.

[0072] To be able to return the device to the safety position, for example to change the perforation zone while limiting the risk of accidental puncture of said practitioner and / or the patient, the distal blades 10 - respectively proximal - are each provided with upper gripping surfaces 14 - respectively lower 15, which are arranged so as to allow an arrangement of the respective surfaces 14, 15 of two adjacent blades 10, 11 in vertical view when said device is in the position of use. Thus, the practitioner can grasp two facing surfaces 14, 15 by pinching them between two of his fingers to release the lug 9 from the distal stop 8a, and thus allow the device to return to the safety position by elastic return of the blades 10, 11.

[0073] Advantageously, the device is arranged to allow it to be switched between its safety and use positions several times, in particular of the order of five times, in order to allow the practitioner to carry out several injections on the same patient during the same intervention, by carrying out several perforations of the skin by means of said device. Thus, the practitioner can easily place the device in the safety position after having carried out injections in a first given zone, then replace said device in its use position to continue injections in a second zone, avoiding the risk of accidental pricking for him and / or for said patient between the treatment procedures of said first and second zones.

[0074] The area to be perforated may in particular be located on the patient's face, for example near an ear (retro-mandibular point), in a nasolabial area (at the modiolus, nasolabial point), at the zygomatic bone (zygomatic point), on a temple (temporal or frontal point) or above the glabella (glabellar point). Thus, the practitioner can reach several areas to be treated located on the patient's face and / or neck from the same hole made in said area to be perforated, which makes it possible to limit perforations of the skin, and therefore trauma for the patient. In particular, for an intervention on the face, the number of areas to be perforated may be between one and five for each side of said face.

[0075] The area to be perforated can also be located on any other part of the patient's body, in particular on a hand, an arm or a thigh, on a buttock, on the chest, in particular at the neckline, on the scalp, on the stomach, at the mucous membranes, or even on a foot.

[0076] To puncture the patient's skin, the practitioner, after having prepared said skin, grasps the device with his fingers to place it in the position of use, in particular by carrying out the manipulations presented above, and inserts the sharp distal tip 2a into said skin.

[0077] In particular, depending on the depth at which the area to be treated is located, the practitioner inserts the tip 2a into the skin at an angle relative to said skin, the value of which increases with said depth. Thus, when the area to be treated is superficial, the tip 2a can be inserted into the skin in a direction substantially tangential to said skin. Conversely, when the area to be treated is deep, the tip 2a can be inserted into the skin in a direction substantially perpendicular to said skin.

[0078] Once the patient's skin has been perforated, the method provides for placing the injection cannula 20 on the gutter 2, the sharp tip 2a of the device remaining planted in the skin. Then, the method provides for a subsequent step of sliding the injection cannula 20 beyond the sharp distal tip 2a, in order to introduce the rounded tip 20a under the skin.

[0079] To do this, the gutter 2 is arranged to allow the injection cannula 20 to slide on it beyond its distal tip 2a towards at least one area to be treated located under the patient's skin. In particular, the gutter 2 has an internal dimension which is greater than the external caliber of the injection cannula 20 which must slide on it.

[0080] For example, for a small caliber cannula 20, in particular of the order of 25 gauge (G), or with an outer diameter (OD) of the order of 0.5 mm, the gutter 2 must have an internal dimension of at least 0.65 mm. Similarly, for a large caliber cannula 20, in particular of the order of 14 G, or with an outer diameter of the order of 2.1 mm, the gutter 2 must have an internal dimension of at least 2.26 mm.

[0081] In relation to the figures, the gutter 2 has an open proximal end 2b which is accessible from the proximal wall 1b of the central body 1. Thus, in a particularly intuitive manner, the method can provide for arranging the cannula 20 on the gutter 2 by introducing the rounded end 20a of said cannula into the proximal end 2b, then sliding said rounded end over the entire length of the gutter 2.

[0082] Furthermore, the gutter 2 has an upper slot 30 which is surrounded by an upper wall 1c of the central body, said slot extending over at least part of the length of said gutter, and preferably over the entire length.

[0083] Advantageously, the slot 30 can have a spacing greater than the external caliber of the cannula 20. Thus, to be able to slide the cannula 20 on the gutter 2, the practitioner can place the rounded end 20a at the bottom of the gutter 2, which facilitates the guiding of said cannula towards the area to be treated by sliding on said gutter.

[0084] Alternatively, the slot 30 may have a spacing less than the external caliber of the cannula 20. In this case, the gutter 2 may exert a slight guidance of the cannula 20 by sliding its rounded end 20a against the edges of the slot 30.

[0085] In the embodiment shown, the gutter 2 has a geometry of a longitudinal section of a cylinder, in particular a semi-cylindrical geometry produced by means of a half-needle cut longitudinally at least over part of its length. Thus, the gutter 2 has a geometry of shape complementary to that of the injection cannula 20, which makes it easier to slide said cannula on said gutter.

[0086] In particular, the internal diameter of the gutter 2 depends on the proportion of diameter at which the cylinder section is made, said diameter being all the greater the smaller said proportion. Thus, when the gutter 2 has a semi-cylindrical geometry, its internal diameter corresponds to the spacing of the slot 30 and is greater than the external caliber of the cannula 20, which makes it possible to arrange said cannula on said gutter by arranging the rounded end 20a against the bottom of said gutter.

[0087] Thus, the practitioner can save time compared to conventional injection techniques, because he does not have to locate the hole formed by perforation, since the device used for said perforation remains positioned in said hole and access to the area to be treated is materialized by the gutter 2, which is easily located. As a result, the practitioner therefore does not need to resort to practices that are traumatic for the patient, such as pinching the skin of said patient several times to locate the hole, risking it bleeding, or to perform an additional perforation of said skin in the event of loss of visibility of the previous hole.

[0088] Furthermore, thanks to the guidance of the cannula 20 by the gutter 2, the practitioner fumbles less during the introduction of said cannula, which also proves to be less traumatic for the patient.

[0089] In addition, the operations of handling the perforation device are limited, which makes it possible to limit the risks of accidental puncture for the practitioner and the risk of loss of sterility of the sharp point 2a of said device.

[0090] Depending on the depth of the area to be treated and / or its location relative to the access hole, the cannula 20 may be introduced under the skin in various angular directions relative to said skin. In particular, the cannula 20 may be introduced in a direction substantially tangent to the surface of said skin, in particular if the product is to be injected into a single area or into several areas substantially located on the same progression path. On the contrary, the cannula 20 may be introduced in a direction substantially perpendicular to the surface of the skin, in particular if the product is to be injected into several areas located in distinctly different directions. In addition, the thickness of the skin and / or its texture may also influence the angle of introduction of the cannula 20.

[0091] Consequently, to correctly guide the cannula 20 towards the area(s) to be treated, the gutter 2, and therefore the device, must be oriented in the angular direction of introduction of said cannula when inserting the sharp point 2a into the skin, the practitioner must also maintain said device in said orientation at least until the rounded end 20a of said cannula is introduced under said skin.

[0092] To do this, the distal blades 10 in the close position are arranged to each form, with the adjacent proximal blade 11, a lateral arm 16 for gripping and manipulating the device in the position of use.

[0093] In the embodiment shown, the arms 16 have, due to the configuration of the blades 10, 11, an elongated shape, and extend symmetrically on either side of the sagittal plane S, each arm 16 also having a surface 17 for holding the finger in the position of use of the device.

[0094] In particular, the elongated shape of the gripping arms 16 and their lateral arrangement on either side of the gutter 2 allows the practitioner to easily grasp the device by holding only one of said arms by its finger holding surface 17, in particular on a front central portion 18 and on an opposite rear portion 19 formed respectively on the distal blade 10 and the proximal blade 11, for example by pinching said arm between his thumb and index finger.

[0095] Thus, the hand of the practitioner holding the device in the position of use can be easily positioned away from the sagittal direction s of the gutter 2 and the sagittal plane S, and therefore from the guide axis of the cannula 20, and this without forcing said practitioner to adopt with said hand an uncomfortable and potentially painful position in the long term for his wrist. As a result, the practitioner can easily position and slide the cannula 20 on the gutter 2 using his other hand, without his two hands interfering with each other.

[0096] In particular, the stop 8a and the lug 9 make it possible to lock the device in the position of use, which makes it possible for the practitioner to avoid having to permanently pinch the blades 10, 11 between his fingers, and thus to guarantee said practitioner greater freedom of movement to manipulate said device in said position of use.

[0097] In relation to [Fig. 1e], the lateral arms 16 each extend in a transverse direction D which forms with the sagittal direction s an angle a of between 30° and 85°, and in particular 65°.

[0098] This angular range offers a good compromise to both facilitate the holding of the device by two-finger gripping of one of its arms 16 and limit the size of the axis of the gutter 2 by the hand holding said device.

[0099] Indeed, for optimal holding of the device by bi-digital gripping, the transverse direction D of the arms 16 must not be too far from the sagittal plane S, so as not to move the axis of the force to be provided to prick the skin too far away from the direction s of the gutter 2. In particular, when the angle a is greater than 85°, the device is unsuitable for holding by bi-digital gripping, because such holding generates a cantilever effect which is hindering the perforation of the skin.

[0100] Furthermore, the smaller the angle a, the closer the skin pricking force is to the direction s, but in return the hand encumbers the direction s of the gutter 2 more, which proves to be troublesome for guiding the cannula 20. In particular, when the angle a is less than 30°, the ergonomics of the device is compromised in that the practitioner's hands get in each other's way, which forces said practitioner to adopt an uncomfortable and potentially painful posture with the hand holding the device, for example by placing said hand substantially flat relative to the patient's skin and at an unnatural angle relative to his wrist.

[0101] Advantageously, the angle a is between 45° and 80°, and more particularly between 65° and 80°, which gives the device optimal ergonomics.

[0102] Furthermore, for an angle a of between 30° and 40°, the shape of the arms 4 can be adapted to further free the direction s of guidance of the cannula. In particular, the blades 10, 11 in the user position can be arranged to give the arms 16 a curved shape along their transverse direction D, the radius of curvature of said shape also being sufficiently large, in particular greater than 20 mm, to facilitate gripping of the arms 16.

[0103] Furthermore, each blade 10, 11 has a proximal end secured near the proximal wall 1b of the central body 1, the front central portion 18 of each arm 16 having a center C which extends at a distance e of approximately 10 mm from the proximal end of the blade 10, said center corresponding to the epicenter of the pressure exerted by the finger when the practitioner grasps the arm 16. It will be noted that the length of each arm 16 does not significantly influence the ergonomics and therefore does not significantly influence the position of the epicenter C.

[0104] In particular, the front central portion 18 of each finger holding surface 17 is located, in particular at the level of its epicenter C, at a distance d of between 8 mm and 30 mm from the distal end 1a of the central body 1, such a range of values ​​corresponding to the average thicknesses of a finger.

[0105] Thus, when the practitioner holds the device by placing his index finger on the front central portion 18 of the digital holding surface 17 of an arm 16 and his thumb on the rear portion 19 of said surface, then pricks the skin while thus holding said device, his index finger is placed between the skin and said arm, in particular when the sharp point 2a is inserted at an angle substantially perpendicular to said skin, and this without hindering said insertion. Furthermore, if the distance d is sufficiently small, the index finger can be as close as possible to the skin, and in particular resting between the gripping arm 16 and said skin, which gives better stability to the device and makes it easier to hold during the introduction of the cannula 20 under the skin.

[0106] In particular, the distance d is between 10 and 25 mm, and in particular equal to 13 mm, which gives the device optimal ergonomics. When the distance d is located below 8 mm, the device is unsuitable for a two-digit grip of an arm 16, in that the finger resting on the front central portion 18a would hinder the perforation of the skin. Furthermore, a distance d located beyond 30 mm does not allow the practitioner to rest his finger against the skin during perforation, and therefore has a negative impact on the precision of said perforation.

[0107] To prevent the practitioner's fingers from slipping on the digital holding surfaces 17, said surfaces each have at least one portion 18 on which extends a succession of raised patterns 26 to aid digital gripping. In Figures 1a to 1c, the patterns 26 extend along the transverse direction D of an arm 16. Alternatively, the patterns 26 may have another configuration, in particular by extending along another direction, for example perpendicular to the transverse direction D.

[0108] In relation to figures 3a and 3b, the distal extension 4 has a lower part 27 which extends under the transverse plane T along a limited height h, in particular less than 2 mm.

[0109] Thus, by limiting the extent of material of the device under the direction s of the gutter 2, and therefore under the sharp point 2a, said device can be oriented so as to insert the sharp point 2a in a direction tangential to the surface of the skin, in order to be able to introduce a cannula 20 in such a direction.

[0110] However, it happens that the practitioner wishes to slide the device along the skin prior to perforation, for example in order to consider the precise location of said perforation, and a height h that is too low would make this manipulation more delicate, in that the practitioner could inadvertently perforate the skin in an inappropriate place.

[0111] The height h can also have a greater value, but must not exceed 2 mm, otherwise the device would be unsuitable for tangential perforation of the skin.

[0112] To improve access to the gutter 2, and therefore facilitate the arrangement of the cannula 20 on said gutter, the upper wall 1c of the body 1 has a clearance zone 28 which extends on either side of said gutter.

[0113] In relation to figures 1a to 1c, the central body 1 has a V-shaped geometry, the upper wall thus forming a flared groove in the center of which the gutter 2 is arranged.

[0114] Furthermore, the gripping arms 16 extend on either side of the sagittal direction in a direction D substantially parallel to the transverse plane T defined by the gutter 2, so as not to hinder access to the gutter 2 via the upper clearance zone 28.

[0115] Similarly, the proximal wall 1b of the central body 1 is surrounded by a rear clearance zone 29 arranged to allow the use of an injection cannula. 20 of short length, in particular by avoiding the risks of collision between the proximal wall 1b of the body 1 and the base 22 of said cannula when the latter is slid onto the gutter 2, then introduced under the patient's skin.

[0116] Once the cannula 20 has been introduced under the skin, the method provides for removing the device in order to extract its sharp tip 2a from said skin, while leaving the cannula 20 introduced under said skin. In particular, the method may provide for removing the device by sliding the gutter 2 relative to the cannula 20 introduced under the skin.

[0117] After having extracted the gutter 2 from the patient's skin, the practitioner must redistribute the device to the safety position, in order to retract the tip 2a into the distal extension 4. To do this, the practitioner can in particular pinch between his thumb and his index finger the respective gripping surfaces 14, 15 of two facing blades 10, 11, in order to allow a return of the device to its safety position by elastic return of said blades.

[0118] Advantageously, the device is arranged to allow the practitioner to tilt it from its use position to its safety position using only one of his hands, in order to allow said practitioner to simultaneously hold the cannula 20 introduced into the skin with his other hand.

[0119] After removing the device, the practitioner has both hands to finish positioning the cannula 20, in particular by sliding said cannula under the skin until its injection orifice 21 reaches an area to be treated, in order to be able to inject the product into said area.

[0120] To facilitate the positioning of the injection orifice 21 in the area to be treated, in particular when the latter is located at a significant depth and / or at a significant distance from the access hole, the cannula 20 may have graduations 23 provided at regular intervals along its length, for example every centimeter.

[0121] Furthermore, the base 22 of the cannula 20 may comprise on its periphery a marking 24 for locating the injection orifice 21 which is aligned with said injection orifice, which allows the practitioner to correctly orient said injection orifice when the latter is positioned in the area to be treated.

[0122] In relation to [Fig.4], the reference marking comprises a point 24 provided on the periphery of the base 22, said point being produced in a color sufficiently visible to contrast with the color of said base.

[0123] Alternatively, the reference marking 24 may have another pattern, in particular in the form of an arrow. It may also be produced in relief on the base 22, for example during the molding of said base, and possibly colored with a different shade from said base.

[0124] To limit the pain felt by the patient during the procedure, the method may provide a step prior to the perforation of the skin, in which an anesthetic product is applied at least on and / or in the area to be perforated, which makes it possible to limit both the pain due to said perforation and the pain due to the introduction of the cannula 20. In particular, the anesthetic product may be applied locally in the form of a cream and / or a patch, for example an Emla® type patch.

[0125] Furthermore, the method may provide for treating several areas in succession, by accessing them from the same access hole. In particular, for injecting the same product into several areas to be treated, the method may provide for moving a cannula 20 already introduced into the patient's skin to another area to be treated after injecting said product into a first area.

[0126] In particular, the method may provide for a radial movement between the area which has just been treated and a new area to be treated in order to carry out a new injection into said new area.

[0127] Furthermore, the method may provide for repeating at least once such a radial movement from the treated area to another area to be treated and a subsequent step of injecting product into said other area. Thus, the practitioner can treat an entire area of ​​the face, for example the forehead, a temple or a cheek, or an entire area of ​​a part of the body, for example a buttock or the chest, and this from a single access hole.

[0128] To correct sagging skin that extends widely over an area of ​​the face, for example on the forehead, a temple or a cheek, a known technique consists of injecting the product by bolus, that is to say, depositing several small doses of product over the entire area by making several movements in the area, in order to stretch the skin over the entire area while restoring volume.

[0129] In particular, the practitioner can carry out several bolus injections by making several radial movements, in particular in a fan shape, in the same area, then massaging. The practitioner can also use a particular technique called "nappage" which is generally carried out in a layer of the hypodermis, in order to smooth the surface and plump the skin in depth.

[0130] By radially moving the cannula 20 already inserted into the hypodermic layer from an already treated area of ​​said layer to another area to be treated, said cannula remains in particular at a constant depth. Thus, the practitioner ensures that all the coating injections are carried out in the same layer, and in particular at the same depth in said layer.

[0131] As a result, the practitioner can easily plump up a layer under the skin with a constant thickness of product, which helps ensure the homogeneity and harmony of the final result.

[0132] Furthermore, the method may provide for moving the cannula 20 backwards during the bolus injection of the product, i.e. following a retrograde movement, in order to distribute said product over a significant depth range and / or over a wider area, which allows a more harmonious and therefore more natural result. Alternatively, the method may provide for moving the cannula 20 forwards, following an antegrade movement, during the bolus injection of the product.

[0133] Once the injections are complete, the practitioner removes the cannula 20 and can massage the treated area, in order to distribute the product evenly and give a more homogeneous and therefore more natural appearance to the correction made. The patient can then see immediately visible and lasting results.

[0134] In the embodiment shown, the gutter 2 is formed as a separate piece attached to the central body 1, in particular made of metal, and more particularly made of stainless steel such as the SUS 304 alloy and / or the AISI 304 alloy.

[0135] Similarly, the body 1 and the safety member 3 may each be formed by injection of a suitable material, in particular a plastic material, the plastic materials used for said body and said member respectively being able to be identical or different, depending on the desired physical constraints. In particular, the plastic material(s) may comprise a polymer that is harmless to the human or animal body, in particular by being implantable, for example made of acrylonitrile butadiene styrene (ABS), polypropylene or a polypropylene-based copolymer, such as ethylene-polypropylene. In general, the body 1 and the safety member 3 may be made of a non-flammable material, in particular one that is pyrogen-free.

[0136] Advantageously, the blades 10, 11 are formed in a single piece with the member 3 or the body 1, in particular during an injection process as described previously.

[0137] The gutter 2 can then be attached to the body 1, for example by gluing said gutter to said body or by overmolding said gutter by said body.

[0138] In relation to [Fig. 1a], the device comprises a half-needle 31 whose distal portion 31a is cut along its length to form the gutter 2, the uncut proximal portion 31b being arranged to be glued or overmolded to the body 1 to allow the association of said gutter with said body.

[0139] To facilitate the reliable positioning of the gutter 2 in the body 1 during gluing, an excess thickness, preferably 3 to 5 mm in length, may be provided in the proximal part of the upper wall forming a flared groove. This excess thickness may be pierced with a hole capable of receiving the tubular portion 31b of the needle 31, so that the latter is retained and positioned in a constrained and reliable manner during gluing. The excess thickness must be of small thickness, preferably less than 15 / 10ths of a millimeter so that it does not interfere when the practitioner inserts the cannula 20 into the hole made by the device.

[0140] Furthermore, the upper wall 1c comprises a distal groove 32 which extends in longitudinal alignment with the receiving hole of the tubular portion 31b, and in which a proximal portion of the gutter 2 is intended to be arranged.

[0141] The device thus manufactured can then be packaged with at least one cannula 20 with a rounded tip 20a to form an injection kit. To do this, the device and the cannula 20 of the same kit can be packaged in the same transparent sterile bag, in particular based on polypropylene and / or polyethylene, said bag can also be flexible or rigid and / or comprise at least one portion based on peelable paper.

[0142] Furthermore, the kit thus packaged can be stored in a box containing other kits also packaged in sachets, in order to be protected from humidity and light during their storage.

[0143] In particular, the central body 1 of the device may have a coloring identical to that of the base 22 of the cannula 20, which makes it possible to identify said device and said cannula as belonging to the same injection kit. As a result, the practitioner can identify, among several kits packaged in sachets, the kit he needs just by looking at the color of the base 22 and the central body 1.

[0144] The device can also be packaged alone, in particular in a bag such as as described above, in order to be marketed alone, in particular for sale to laboratories.

[0145] Furthermore, after packaging in a sachet, the device or the device / cannula kit 20 are sterilized, for example by means of a sterilization process using ethylene oxide (ETO), ionizing radiation or steam.

[0146] In addition, the sachet may include information for the practitioner, such as a batch number, the dimensions of the cannula 20 and / or the device, a concept restricting use to qualified practitioners, a reference to the notified body and / or a marking of conformity to a standard, in particular the CE standard.

[0147] In particular, the sachet may include information useful for safe use of the device or device / cannula kit 20 contained therein, for example a sterilization date and / or an expiry date. Furthermore, if the sachet is in poor condition and / or opened, the practitioner can immediately know that the device or kit contained in said sachet must be destroyed for the safety of the patient.

Claims

Claims

1. Device for introducing a cannula (20) with a rounded tip (20a) under the skin of a patient for the purpose of injecting a biocompatible product, said device comprising a central body (1) equipped with a groove (2) which extends in a sagittal direction (s) having a sharp distal tip (2a) projecting from a distal end (la) of said body for perforating said skin, said groove being arranged to allow the cannula (20) to slide thereon beyond said distal tip towards at least one area to be treated located under said skin, said device being characterized in that it further comprises a safety member (3) relative to which the body (1) is mounted in relative mobility between two stable positions, respectively a safety position and a use position,said member comprising a distal extension (4) in which the sharp distal tip (2a) is fully arranged - respectively fully protruding - in the safety position - respectively in the use position.,

2. Device according to claim 1, characterized in that the distal extension (4) comprises a housing (5) which extends in the sagittal direction (s) and in which the body (1) is mounted to move in sagittal sliding.

3. Device according to claim 2, characterized in that the housing (5) has an internal geometry which is complementary to the external geometry of the body (1).

4. Device according to one of claims 2 or 3, characterized in that the housing (5) comprises a bottom in which a sagittal groove (6) is formed, the body (1) comprising a lower part (Id) on which a sagittal rail (7) is formed which is mounted in relative sliding in said groove.

5. Device according to any one of claims 1 to 4, characterized in that the body (1) comprises a lower part (Id) on which are formed two stops, respectively distal (8a) and proximal (8b), aligned in the sagittal direction (s), the distal extension (4) having a proximal lug (9) arranged to come to bear against the distal stop (8a) - respectively proximal (8b) - in the safety position - respectively in use.

6. Device according to any one of claims 1 to 5, characterized in that the safety member (3) - respectively the body (1) - comprises two distal blades (10) - respectively proximal (11) - which extend laterally on either side respectively of said member and of said body while being symmetrical with respect to the sagittal direction (s), a distal blade (10) being mounted in relative mobility with respect to an adjacent proximal blade (11) between a position spaced apart - respectively brought together - from said proximal blade to allow the arrangement of said device in a stable safety position - respectively of use.

7. Device according to claim 6, characterized in that one of the distal blades (10) and the proximal blades (11) each comprises a free end provided with a pivot (12) which is rotatably mounted in a complementary ball joint (13) formed on respectively a free end of the other of the proximal blades (11) and the distal blades (10), in order to allow the relative movement of the body (1) with respect to the safety member (3) by rotation of said pivots in said ball joints.

8. Device according to one of claims 6 or 7, characterized in that the distal blades (10) in the close position are arranged to each form, with the adjacent proximal blade (11), an arm (16) for gripping and manipulating the device in the position of use.

9. Device according to claim 8, characterized in that the gripping arms (16) each extend relative to the sagittal direction (s) in a transverse direction (D) which forms with said sagittal direction (S) an angle (a) of between 30° and 85°.

10. Device according to any one of claims 1 to 9, characterized in that the gutter (2) has an open proximal end (2b) which is accessible from a proximal wall (1b) of the central body (1), said proximal wall being surrounded by a rear clearance zone (29).

11. Device according to any one of claims 1 to 10, characterized in that the gutter (2) has an upper slot (30) which extends over at least part of the length of said gutter and which is surrounded by an upper wall (le) of the central body (1).

12. Kit for injecting a biocompatible product, said kit comprising an introduction device according to any one of claims 1 to 11 as well as at least one injection cannula (20) with a rounded tip (20a), the gutter (2) being arranged to allow said at least one cannula to slide on it beyond its distal tip (2a) towards at least one area to be treated located under the skin of a patient.

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