Eye injection device

Abstract

An injection device for injecting a product into an eye, said device comprising an injection needle and a support on which the injection needle is fixed, said device being characterized in that it comprises a locating mark disposed in such a way that the latter can be placed in contact with a defined bearing region of the surface of the eye, before any contact of the injection needle with said surface, and can then be kept in contact with said bearing region during a stage of penetration of said injection needle through said surface of the eye.

Claims

1. An electroporation device for injecting a product into a ciliary muscle of an eye having a cornea having an edge, said device comprising: at least one injection needle to inject said product in an injection zone; a support on which the at least one injection needle is fixed or which is able to guide a sliding movement of the at least one injection needle; a locating mark fixed on the support and disposed, along an arc of a circle with a radius of greater than 5 mm and of less than 8 mm, in such a way that said locating mark can be placed in contact with a defined bearing region of a surface of the eye, before any contact of the at least one injection needle with said surface, and can then be kept in contact with said bearing region during a stage of penetration of said at least one injection needle through said surface of the eye, the bearing region being at least a part of the edge of the cornea of the eye, said penetration resulting from a rotation of the support about the locating mark when said at least one injection needle is fixed on the support; and an assembly of electrodes composed of first and second sets of electrodes designed to be connected electrically to first and second terminals, respectively, of an electrical generator in such a way as to create, within the injection zone, an electrical field that promotes electroporation, wherein, in a position of use preventing further penetration of said at least one injection needle, said at least one injection needle penetrates into the spherical envelope via a point of penetration and extends inside said spherical envelope to a depth less than 1.5 mm.

2. The device as claimed in claim 1, wherein the length of said arc of a circle is less than 20 mm.

3. The device as claimed in claim 1, wherein, in said position of use, said at least one injection needle extends inside said spherical envelope to a depth greater than 0.5 mm.

4. The device as claimed in claim 1, wherein the support comprises an abutment face extending substantially along a spherical envelope matching the sclera of the eye.

5. The device as claimed in claim 4, wherein the at least one injection needle and a straight line intersecting the abutment face perpendicularly at its center, or main axis of the abutment face extend in parallel planes, and in which, in a projection in one of these planes, the direction of the at least one injection needle forms an angle of greater than 50 with the main axis of the abutment face.

6. The device as claimed in claim 4, wherein the abutment face extends laterally over an angle sector of greater than 45 and less than 135.

7. The device as claimed in claim 4, wherein the abutment face does not extend over more than a quadrant of a hemisphere.

8. The device as claimed in claim 4, wherein the radius of curvature of said spherical envelope is greater than 9 mm, and less than 14 mm.

9. The device as claimed in claim 4, wherein the locating mark is a locating line in the shape of an arc of a circle having an axis, said axis passing through the center of said spherical envelope.

10. The device as claimed in claim 4, wherein the locating mark extends along a locating line in the shape of an arc of a circle, said at least one injection needle penetrates into the spherical envelope via a point of penetration and, in a plane passing through the center of said spherical envelope, via said point of penetration, and perpendicularly intersecting said arc of a circle, the distance between said point of penetration and the point of said arc of a circle through which said plane intersects said arc of a circle is greater than 1 mm and less than 3 mm.

11. The device as claimed in claim 4, in which said at least one injection needle penetrates into the spherical envelope via a point of penetration and, in a plane passing through the center of said spherical envelope, via said point of penetration, and perpendicularly intersecting said arc of a circle, the distance between said point of penetration and the point of said arc of a circle through which said plane intersects said arc of a circle is greater than 1 mm and less than 3 mm, said needle extending inside said spherical envelope to a depth (.sub.1) greater than 0.5 mm and less than 1.5 mm.

12. The device as claimed in claim 1, wherein the locating mark is formed by a locating line that can match the edge of the cornea of the eye.

13. The device as claimed in claim 1, wherein the locating mark is designed to bear on more than 5 mm of the edge of the cornea.

14. The device as claimed in claim 1, comprising one or more non-invasive electrodes designed to come into contact with the surface of the eye, and configured so as to match the shape of the surface of the eye.

15. The device as claimed in claim 1, in which the support has a concave, substantially spherical surface being designed to serve as abutment means that are able to limit the movement of the support during the stage of penetration, and being covered, at least in part, by an electrically conductive cover that serves as an electrode.

16. The device as claimed in claim 1, wherein said first set of electrodes comprises a plurality of invasive electrodes.

17. An electroporation device according to claim 1, comprising an invasive electrode which is able to be guided in a sliding movement on the support.

18. Method for injecting a product into a ciliary muscle of an eye using the device claimed in claim 1, said method comprising: a) placing the locating mark in contact with a bearing region of the surface of the eye, b) causing the penetration of said at least one injection needle in the eye while keeping said locating mark in contact with said bearing region, said penetration being achieved by sliding the at least one injection needle relatively to the support, the support having been immobilized by being pressed on the surface of the eye, c) injecting the product, d) generating an electrical field between said first set of electrodes and said second set of electrodes, the electrical field being adapted to promote said electroporation.

19. An electroporation device for introducing a product into a ciliary muscle of an eye, said device comprising: at least three invasive electrode needles, which extend parallel to each other along a direction, a support which is able to guide a sliding movement of the at least three needles along the axis of the at least three needles until a needle abutment position, the support comprising an abutment face extending substantially along a spherical envelope matching the sclera of the eye, a non-invasive electrode extending along said spherical envelope, a locating mark which can be placed in contact with a defined bearing region of a surface of the eye, before any contact of the needles with said surface, and can then be kept in contact with said bearing region during a stage of penetration of the needles through said surface of the eye, the bearing region being at least a part of an edge of a cornea of the eye, at least one injection needle, wherein, in a position of use preventing further penetration of said at least one injection needle, said at least one injection needle extends inside said spherical envelope to a depth of less than 1.5 mm.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) Other features and advantages of the invention will become clear upon reading the following detailed description and by examining the attached drawing, in which:

(2) FIG. 1 shows, in perspective, a first embodiment of an injection device according to the invention for injection, with electroporation, of a product into a ciliary muscle of an eye;

(3) FIG. 2 shows a plan view of this device;

(4) FIGS. 3 and 4 show, along the transverse median plane A-A and the transverse plane B-B shown in FIG. 2, cross sections of the device shown in FIG. 1;

(5) FIG. 5 shows, in perspective, a second embodiment of a device according to the invention;

(6) FIG. 6 shows the shape of an abutment face of a device according to the invention, in a preferred embodiment;

(7) FIG. 7 is a highly schematic depiction of a device according to the invention during a stage of penetration. In FIG. 7, it is possible to visualize the angle between the direction of penetration of an injection needle at the point of penetration into the eye and the direction of this injection needle;

(8) FIG. 8 shows, along a median transverse plane, a cross section of a device according to the invention in a third embodiment;

(9) FIG. 9 shows the quantity of hTNFr-Is that has been able to penetrate into cells depending on whether the injected dose has been injected at one injection point or at several injection points,

(10) FIG. 10 shows a detail of FIG. 3; and

(11) FIG. 11 shows a partial view of the device depicted in FIG. 10, as observed along the axis Dc.sub.0 by the observer Obs in FIG. 10.

(12) In FIGS. 10 and 11, the device has been shown in a position of use, that is to say at the end of the stage of penetration, the spherical envelope S schematically representing the sclera of an eye, and Co schematically representing the cornea of this eye.

(13) In FIG. 11, only the parts of the needles situated inside the spherical envelope S are shown, in broken lines.

(14) In the various figures, identical reference signs are used to designate identical or similar elements. In FIG. 5, the reference signs are complemented by a sign. In FIG. 8, they are complemented by a sign.

(15) Definitions

(16) The stage of penetration of an injection needle corresponds to the entire stage during which the injection needle penetrates normally into the eye.

(17) Normal penetration of the injection needle is understood as a penetration substantially in the local direction of the injection needle at the point of penetration of this injection needle into the eye, that is to say at the point on the surface of the eye through which the injection needle passes this surface. Such a penetration corresponds to the movement for which an injection needle is designed, so as to avoid the insertion of the needle needlessly damaging the surface of the eye.

(18) The locating mark and the injection needle can be designed such that, throughout the stage of penetration of said injection needle into the eye, the local direction of the injection needle at the point of penetration into the eye forms, with the direction of its forward movement at said point of penetration, or direction of penetration, an angle that is always less than an angle of maximum spacing .sub.max of 15, preferably 10, or 5.

(19) The local direction of the injection needle at the point of penetration into the eye is defined by the tangent to the injection needle at the point of the eye through which the needle penetrates into the latter. In the case of a rectilinear needle, this direction is defined by the axis of the needle.

(20) The direction of the forward movement at the point of penetration is the direction of the speed vector of the region of the needle situated at said point of penetration. When the needle penetrates by means of a rotation of the support about a bearing point, this direction is thus defined by the tangent, at the point of penetration, to the circle centered on this bearing point and passing through said point of penetration.

(21) For example, with a rectilinear needle, normal penetration corresponds to a movement of the needle along the axis of the needle. The direction of penetration then forms a constant angle, throughout the stage of penetration, with the surface of the eye at the point of penetration of said injection needle. This angle can be 90, although normal penetration is not limited to this angle.

(22) The stage of penetration preferably lasts from the first contact of the injection needle with the surface of the eye until a position of use.

(23) The main axis of a surface is the direction perpendicular to a surface passing through its center.

(24) In the present description, the adjectives upper and lower are defined with respect to a vertical direction V as shown in FIGS. 1, 3 and 4.

(25) The adjectives right-hand and left-hand are defined with respect to the view in FIG. 2.

(26) A quadrant of a hemisphere designates a quarter of the surface of this hemisphere obtained by cuts in two perpendicular planes that intersect along the main axis of the hemisphere.

(27) In the present description, unless otherwise stated, comprising a should be understood as comprising at least one.

DETAILED DESCRIPTION OF AN EMBODIMENT

(28) The injection device 10 shown in FIGS. 1 to 4 comprises a support 12 on which are fixed three identical and rectilinear injection needles 14.sub.1, 14.sub.2 and 14.sub.3 oriented parallel to one another in a needle direction D.sub.needle.

(29) The three injection needles belong to one and the same plane, called the plane of the needles and designated P.sub.needles.

(30) In order to be secured on the support 12, the injection needles are sandwiched between a main part 12a of the support 12 and a blocking piece 12b, which is fixed on the main part 12a, for example by clipping, by adhesive bonding or by fusion of material.

(31) The needle 14.sub.2 extends at an equal distance between the needles 14.sub.1 and 14.sub.3. The distance d.sub.1 between the needle 14.sub.2 and the needles 14.sub.1 and 14.sub.3 can be greater than 3 mm or 3.5 mm or 4 mm and less than 6 mm or 5.5 mm. In particular, it can be about 4.5 mm (FIG. 2).

(32) Since the three needles are identical and are fixed in a described in detail, with reference to FIG. 4. For a given reference sign, the indices 1, 2 and 3 relate to the injection needles 14.sub.1, 14.sub.2 and 14.sub.3, respectively.

(33) The needle 14.sub.1 extends from a proximal end 16.sub.1, embedded in the support, to a distal end 17.sub.1 with a beveled tip, for facilitating the penetration of the needle into the eye, and opening out via an axial ejection orifice. The distal ends 17.sub.1, 17.sub.2 and 17.sub.3 of the three needles 14.sub.1, 14.sub.2 and 14.sub.3 extend substantially in an arc of a circle F.sub.17, as is shown in FIGS. 2 and 11. The needle 14.sub.1 is traversed in the normal way by a lumen 18.sub.1, which is designed for the transfer of product from the proximal end to the distal end. The external diameter of the needle 14.sub.1 is, for example, about 0.3 mm.

(34) The injection needle 14.sub.1 comprises a protruding part 22.sub.1, that is to say protruding from the support, and an engaged part 24.sub.1, embedded in the support. The length l.sub.22 of the protruding part 22.sub.1 can be, for example, between 3.3 and 3.7 mm, an ideal length being 3.5 mm. The protruding parts of the three injection needles can have a substantially identical length.

(35) The protruding part 22.sub.1 of the needle 14.sub.1 is covered along part of its length by an insulating cover 34.sub.1. The insulating cover 34.sub.1 can continue along the engaged part of the injection needle 14.sub.1 and can even completely cover this engaged part.

(36) The proximal ends of the needles open into a common distribution channel 20 in fluid communication with the outside of the support. The distribution channel 20 thus allows product to be delivered from outside the support to the proximal ends of the injection needles, and then, by way of the lumens of these injection needles, to the distal ends of the injection needles. The diameter d.sub.20 of the distribution channel 20 can be greater than 0.5 mm or 0.6 mm and/or less than 0.9 mm or less than 0.8 mm, an ideal diameter being 0.7 mm.

(37) The device also comprises means (not shown) for plugging one or more of the needles or for plugging the inlet of the distribution channel 20.

(38) The injection needles protrude from the support 12 through an insertion face 26 of substantially spherical shape, that is to say carried by a spherical envelope, so as to remain spaced apart from the surface of the eye in the position of abutment of the support, such that the user can observe the point of penetration of the needle.

(39) The insertion face 26 is inclined with respect to the direction D.sub.needle, and it then joins an intermediate face 36 which is substantially flat, substantially parallel to the plane of the needles P.sub.needles and spaced apart by a defined distance d.sub.36 from this plane, in such a way that the distance between the locating mark, in the form of a band 50 which will be described later, and the points of penetration of the different needles into the spherical envelope S, corresponding substantially to the surface of the eye in the position of abutment of the support, is about 4 mm.

(40) At the opposite end from the insertion face 26, the intermediate face 36 is continued by an abutment face 40. The abutment face 40 extends along a spherical envelope S with center C and radius R, as is shown in FIGS. 4, 6 and 10. The radius R is about 14.75 mm and corresponds to the radius of the outer surface of the eye, in the region of the sclera, near the cornea.

(41) The main axis D.sub.40 of the abutment face 40 is the straight line intersecting the abutment face 40 perpendicularly at its center C.sub.40. The main axis thus passes through the center C of the spherical envelope S. It is included in the median plane A-A shown in FIG. 2 (see also FIG. 10).

(42) In the plane perpendicular to the plane of the needles P.sub.needles and including the needle 14.sub.1, the abutment face 40 extends over an angle sector 8 of, for example, greater than 30 and less than 40, for example about 36 degrees.

(43) In the plane of the needles P.sub.needles, the abutment face 40 extends over an angle sector of, for example, greater than 80 and less than 90.

(44) The abutment face 40 is delimited by two large sides, namely an upper edge 42 and a lower edge 44, which are substantially parallel and circular and which extend in planes substantially parallel to the plane of the needles P.sub.needles, and by two small sides, namely a right-hand lateral edge 46 and a left-hand lateral edge 48, which are also substantially parallel and circular and which extend in planes substantially parallel to the median plane A-A.

(45) As is shown in FIG. 6, in which the spherical envelope S is shown, the upper edge 42 and lower edge 44 thus extend along parallels P.sub.44 and P.sub.42 with radii R.sub.44 and R.sub.42, respectively, the parallels being defined with respect to an axis NS, while the right-hand and left-hand lateral edges 46 and 48 extend along parallels P.sub.46 and P.sub.48, with radii R.sub.46 and R.sub.48 respectively, defined with respect to an axis WE perpendicular to the axis NS and intersecting the latter at the center C.

(46) The radius R.sub.42 can be greater than 8 mm, or greater than 8.5 mm, or 8.8 mm, or 8.9 mm and/or less than 10 mm or less than 9.5 mm, or 9.2 mm, or 9.1 mm or even 9 mm. The radius R.sub.42 can in particular be 8.94 mm. The radius R.sub.44 is defined in such a way that the lower edge 44 can match the edge of the cornea.

(47) The radius R.sub.44 can be greater than 6 mm or 6.4 mm or even 6.5 mm and/or less than 7 mm, or 6.8 mm, or even 6.7 mm. A radius R.sub.44 of 6.58 mm is ideal.

(48) Seen from the front, the abutment face 40 thus has a substantially rectangular shape, of which the center C.sub.40 is half way between the lower edge 44 and the upper edge 42 and between the right-hand lateral edge 46 and the left-hand lateral edge 48.

(49) The corners 49.sub.d and 49.sub.g between the lower edge 44 and the right-hand and left-hand lateral edges 46 and 48, respectively, are preferably rounded in order to limit the risks of injury. The radius of curvature of the rounded corners can be 1 mm, for example.

(50) The distance between the right-hand and left-hand lateral edges 46 and 48, as measured in the direction WE, can be greater than 17 mm, 19 mm or 20 mm and/or less than 25 mm, 23 mm or 22 mm. It can be 21.11 mm, for example.

(51) The distance between the upper edge 42 and lower edge 44, as measured in the direction NS, can be greater than 1.9 mm, 2.2 mm, or 2.3 mm and/or less than 3 mm, 2.6 mm, or 2.5 mm. A height of 2.4 mm is ideal.

(52) In the embodiment shown, the lower edge 44 is delimited by a band 50 of flexible material, for example of silicone. The rest of the abutment face 40 is covered by an electrically conductive cover 52.

(53) As will be seen later in the description, the band 50 is a locating mark, and the cover 52 can serve as a non-invasive electrode.

(54) In the sectional plane of FIG. 4, the distance D.sub.50 between the band 50 and the point of penetration P.sub.1 of the injection needle 14.sub.1 into the spherical envelope S is preferably greater than 1 mm, greater than 2 mm, greater than 3 mm, greater than 3.5 mm and/or less than 6 mm, less than 5 mm, or less than 4.5 mm. This feature preferably applies to each of the needles, in each case considering a sectional plane containing the needle in question and extending parallel to the plane B-B. A distance of 4 mm is ideal.

(55) As is shown in FIG. 11, the band 50 constitutes a locating line that extends in an arc of a circle F.sub.50 whose radius R.sub.50 is substantially equal to the radius of the edge E of the cornea Co, that is to say preferably between 5 and 8 mm, preferably between 6 and 7 mm. The center of the arc of a circle F.sub.50 is designated C.sub.50. Its axis is designated D.sub.Co and passes substantially through the center C of the spherical envelope on which the abutment face 40 extends.

(56) In the position of use, the abutment face thus bears completely on the sclera of the eye, and the locating mark bears completely on the edge of the cornea.

(57) With i designating the index sign of the needle 14.sub.i, the following designations apply: P.sub.i is the point of penetration of the needle 14.sub.i into the spherical envelope S, corresponding virtually to the sclera of the eye; Pl.sub.i is the plane passing through the center C of the spherical envelope S, through the point of penetration P.sub.i and intersecting perpendicularly the arc of a circle F.sub.50 (the median sectional plane A-A thus corresponding to the plane Pl.sub.2); Q.sub.i is the point of the arc of a circle F.sub.50 through which the plane Pl.sub.1 intersects the arc of a circle F.sub.50; l.sub.1 is the distance between the points Q.sub.i and P.sub.i;

(58) .sub.i is the minimum distance between the surface of the spherical envelope S and the distal end 17.sub.i of the needle 14.sub.i, or depth .sub.i; .sub.i is the angle, with the center C as its apex, between the point Q.sub.i and the point of penetration P.sub.i.

(59) In the planes Pl.sub.1, Pl.sub.2 and Pl.sub.3, the spherical envelope S is thus intersected along a great circle, and the cornea Co, intersected through its center, has a cross section of substantially maximum area.

(60) All the points of penetration P.sub.i of the needles 14.sub.i belong to one and the same circle F.sub.p. The distal ends 17.sub.1, 17.sub.2 and 17.sub.3 of said needles belong to one and the same circle F.sub.17. The circles F.sub.50, F.sub.p and F.sub.17 are coaxial with axis DC.sub.0. Whichever needle is considered, the distance between the center C and the distal end of said needle, R.sub.17, is substantially constant. The same applies to the depth .sub.i of said distal ends with respect to the surface of the spherical envelope S. Finally, whichever needle is considered, the angle is substantially the same.

(61) Whichever needle 14.sub.i is considered, the distance l.sub.i is greater than 1 mm, preferably greater than 1.5 mm, more preferably greater than 1.8 mm and less than 3 mm, preferably less than 1.5 mm, more preferably less than 1.2 mm, and the depth .sub.i is greater than 0.5 mm, preferably greater than 0.6 mm, more preferably greater than 0.8 mm, and less than 1.5 mm, preferably less than 1.3 mm, more preferably less than 1.2 mm. This embodiment is particularly ideal for an injection into the ciliary muscle of the eye.

(62) In another embodiment (not shown), whichever needle 14.sub.i is considered, the distance l.sub.i is greater than 2 mm, preferably greater than 3 mm, and less than 4.5 mm, preferably less than 4 mm, or less than 3.5 mm, and the distance .sub.i is greater than 6 mm, preferably greater than 8 mm, and less than 15 mm, preferably less than 13 mm. This embodiment is particularly ideal for an injection into the vitreous body.

(63) The angle , between the main axis D.sub.40 of the abutment face and the needle direction D.sub.needle of the needle 14.sub.2 is between 50 and 60 degrees, for example about 55 degrees (FIG. 10). Advantageously, such angles allow the locating mark 50 bearing on the edge of the cornea to be positioned ideally for an injection into the ciliary muscle.

(64) The angle , the distance d.sub.36 and the length of the needles are determined in such a way that the needles can penetrate into the eye to a depth of greater than 700 m and less than 3 mm in the position of abutment of the support. Advantageously, this depth permits particularly effective injection into the ciliary muscle.

(65) The device shown also comprises a handle 60 to facilitate its manipulation. The overall length L of the device is, for example, about 35 mm, and its overall width l is, for example, about 21 mm (FIG. 3).

(66) In the embodiment shown, the device also comprises means for electrically connecting one or more of the injection needles to the terminals of a generator of an electrical signal. For example, the two injection needles 14.sub.1 and 14.sub.3 can be electrically connected to a first of the terminals of this generator, while the central injection needle 14.sub.2 can be connected to the other terminal of this generator.

(67) The device can also comprise means for electrically connecting the cover 52 to one of the terminals of the generator.

(68) As is shown in FIG. 4, the support can in particular comprise conduits 62 permitting the introduction of pins for electrical connection to one or more of the injection needles, or to all the injection needles. The electrical current can preferably be transmitted by way of the distribution channel 20, for example if this channel comprises a wall 64 made of an electrically conductive material.

(69) In the preferred embodiment of the invention, the three needles 14.sub.1, 14.sub.2 and 14.sub.3 are electrically connected to a first terminal of the generator, while the cover 52 is connected to the second terminal of this generator.

(70) FIG. 5 shows a variant of the device described with reference to FIGS. 1 to 4. In this variant, the width of the intermediate face 36 is reduced in order to minimize the overall size and in order thereby to facilitate the positioning of the device between the two eyelids of a subject who is conscious. FIG. 5 also shows the pins 70 and 72 permitting the electrical connection, to the terminals of a generator, of a first set of electrodes formed by a cover 52 and a second set of electrodes formed by injection needles 14.sub.1, 14.sub.2 and 14.sub.3.

(71) The device shown in FIG. 5 also has a product reservoir 74 in fluid communication with a distribution channel (not shown) common to the three injection needles. Means (not shown) are also provided for transferring the product, for example a piston that can discharge the product out of the reservoir into the distribution channel.

(72) FIG. 8 shows a variant of a device according to the invention designed in particular for injection into the vitreous cavity of an eye.

(73) The device shown in a median cross section in FIG. 8 comprises a support 12 and a single injection needle 14.

(74) The support 12 comprises abutment means, in this case an abutment face 40 that extends along a spherical envelope S. The spherical envelope S corresponds substantially to the surface of the eye in the position of abutment of the support, in which the abutment face 40 is in contact with the surface of the eye. The center C of this spherical envelope thus corresponds substantially to the center of the eye ball.

(75) The length of the injection needle introduced into the eye is much greater than that of the device described above, designed for an injection into the ciliary muscle. This length is preferably between 10 and 13 mm, for example about 12 mm. Such a length of the injection needle would not be able to penetrate, unless the injection needle is curved, by rotation about the band 50, without damaging the surface of the eye if the injection needle 14 were fixed on the support.

(76) It is for this reason that the injection needle 14 is not fixed on the support but instead can slide in a through-orifice 82 of the support between a retracted position (not shown) and a needle abutment position, or deployed position, as shown in FIG. 8.

(77) In order to determine the needle abutment position, the injection needle 14 comprises needle abutment means 80 which can limit the length by which the protruding part 22 of the injection needle 14 projects from the support 12.

(78) The distance D.sub.50 between the locating mark 50 and the point of penetration P of the injection needle 14 into the spherical envelope S is, for example, about 4 mm.

(79) In the embodiment shown, the injection needle 14 has a length such that, in the needle abutment position, its distal end is near the center C.

(80) In one embodiment, the device also comprises means for driving the needle from its retracted position to its deployed position. Advantageously, the deployed position can thus be achieved quickly and effectively, for example by simple manipulation of an actuating button.

(81) The embodiment in FIG. 8 is particularly advantageous for needles that have to penetrate into the eye by a length of greater than 5 mm, greater than 7 mm, or greater than 10 mm and/or less than 15 mm.

(82) To use a device of the kind described in FIGS. 1 to 6, the operator can proceed by the following steps:

(83) First, the operator couples the device to a source of product, for example a syringe filled with product. He then electrically connects the first and second sets of electrodes to the two terminals of an electrical generator. The device is then ready to be applied to the eye into which an injection of product is desired.

(84) To position the device, as shown in FIG. 7, the operator places the locating mark 50 on the edge E of the cornea of the eye O, taking care to ensure that the tips of the injection needles do not come into contact with the eye. The placement on the edge of the cornea advantageously permits a stable but also very precise positioning.

(85) While keeping the locating mark 50 in contact with the edge of the cornea, the operator then causes the injection needles to penetrate through the surface of the eye by rotating the support 12 about the locating mark 50 (arrow F). The three needles penetrate substantially simultaneously through this surface.

(86) As is shown in FIG. 7, at the point of penetration P.sub.1 of the needle 14.sub.1 into the eye O, the direction of penetration V.sub.14 of the needle 14.sub.1 forms an angle .sub.1 with the needle direction D.sub.needle. The arrangement and shape of the needles 14.sub.1, 14.sub.2 and 14.sub.3 allow their respective directions of penetration to form, at their respective points of penetration, angles .sub.1, .sub.2 and .sub.3 with the needle direction D.sub.needle that are substantially equal to . The length of the injection needles and/or their shape are preferably determined in such a way that, throughout the stage of penetration, in this case until the abutment position of the support, this angle remains less than 15, preferably 10, or 5, regardless of the degree of engagement reached.

(87) The shape of the abutment face, in particular the fact that it does not extend over more than one quadrant of a hemisphere, facilitates the positioning of the device and the manipulation thereof during the stage of penetration of the injection needles.

(88) The operator continues the movement of penetration until the abutment face 40, in an abutment position of the support, comes to fit the sclera.

(89) The inventors have shown that human eyes all have very similar dimensions and shapes and, in particular, that the distance between the ciliary muscle and the edge of the cornea of an eye is substantially the same regardless of the individual concerned. The shape and arrangement of the injection needles, of the locating mark and of the abutment face are determined such that, in the abutment position of the support, the operator is guaranteed that the ejection orifices of the injection needles open into the ciliary muscle. In the abutment position of the support, the operator then knows that the injection needles are perfectly positioned and that the product will be properly injected into the ciliary muscle. He then immobilizes the device in this position. The bearing of the abutment face 40 on the sclera and the bearing of the locating mark 50 on the edge of the cornea guarantee a good stability of the device.

(90) The arrangement of the invasive electrodes, in this case the injection needles 14.sub.1, 14.sub.2 and 14.sub.3, with respect to the non-invasive electrode, in this case the cover 52, makes it possible to create an electrical field particularly effective for electroporation.

(91) The operator can then begin the injection of the product by acting on the piston of the syringe.

(92) The operator then sends a suitable electrical signal, for example suitable electrical impulses, by means of the electrical generator, in such a way as to create, within the injection zone, an electrical field that promotes electroporation.

(93) The increase in the local pressure in the area of the injection points is reputed to promote the introduction of the injected product into the cells, particularly in the case of transfection. A person skilled in the art therefore generally considers it preferable to limit the number of injection points, if possible by using only a single injection needle. Surprisingly, however, the inventors have found that multiplication of the injection points promotes the penetration of the product, as can be deduced from FIG. 9. A device with three needles proves particularly effective.

(94) FIG. 9 shows in fact that the result of injecting a volume of 10 l containing 30 g of plasmid coding for a TNF soluble receptor is inferior to that of injecting a volume of 30 l also containing 30 g of said plasmid (hydrodynamic effect), itself inferior to the result of injecting three volumes of 10 l, each containing 10 g of the plasmid, simultaneously from three injection needles.

(95) This demonstrates that multiple injection, that is to say simultaneously through several injection points, is preferable to a single injection of an equal dose of plasmid.

(96) When the injection of the product has been completed, the operator electrically disconnects the electrodes and the generator and then withdraws the injection needles from the eye.

(97) The use of the device shown in FIG. 8 differs from that described for the device shown in FIGS. 1 to 6 in that the positioning of the support can be carried out independently of the penetration of the injection needle 14 into the eye.

(98) First, as has been described above, the operator places the locating mark 50 on the edge of the cornea of the eye, then places the abutment face 40 on this surface, the injection needle 14 being in a retracted position, for example fully withdrawn from the through-orifice 82.

(99) With the support in the abutment position of the support, the operator can then deploy the injection needle from the support and cause the distal end to penetrate into the eye, and he can then push this injection needle as far as the needle abutment position shown in FIG. 8, where the needle abutment means 80 bear on the support 12.

(100) This embodiment of the invention has the advantage of avoiding any accidental contact of the injection needle with the surface of the eye. In addition, it permits penetration of a substantial needle length into the eye.

(101) The other steps of injection and/or of generation of an electrical signal that promotes electroporation are identical to those described above.

(102) The removal of the device shown in FIG. 8 is also particularly advantageous. This is because the operator, when withdrawing the injection needle 14 from the eye, can make use of the guiding action resulting from the sliding of the injection needle 14 in the through-orifice 82, acting as a slide rail for the injection needle 14. The risk of damage to the eye is then particularly low.

(103) As will now be clear, the device according to the invention permits very precise positioning on the surface of the eye, before penetration of an injection needle and/or of an invasive electrode. It also allows said needle(s) and electrode(s) to be guided during the stage of penetration.

(104) Of course, the invention is not limited to the embodiments described and shown, which have been provided by way of illustration.

(105) In particular, the injection needles might not constitute invasive electrodes. The abutment face might also not carry a non-invasive electrode.

(106) Likewise, in other embodiments, the needles might not be injection needles and might instead serve only as invasive electrodes.

(107) In particular, the various embodiments could be combined. It would be possible in particular to use retractable needles or, more generally, needles that are able to slide on the support, with devices designed for treatment of a ciliary muscle, that is to say with relatively small needles.

(108) Finally, the shape of the device is not limited to the one shown. The device could in particular be adapted for injection of product or electroporation in muscles other than the ciliary muscle.