High intensity focused ultrasound device with a concave segment shaped transducers for treatment of ocular pathology

Abstract

A device for treatment of an ocular pathology characterized in that it comprises at least one eye ring (1) wherein the proximal end of said eye ring (1) is suitable to be applied onto the glove and means (2,17) to generate ultrasound beam fixed on the distal end of the eye ring (1), said means to generate ultrasound beam presenting a concave segment shape conformed along a single curvature corresponding to a single direction wherein the concavity is designed to be tuned towards the eyeglobe.

Claims

1. A device for treatment of an ocular pathology comprising; at least one eye ring wherein a proximal end of said eye ring is suitable to be applied onto an eye globe; and a generator fixed on a distal end of said eye ring for generating a high intensity focused ultrasound beam; said generator presenting a concave segment shape conformed along a unique curvature corresponding to a unique direction perpendicular to a revolution axis of said eye ring; wherein said generator includes multiple ultrasound transducers coupled to said eye ring, said transducers are elongated to outwardly radiate away from said axis of said eye ring, and said transducers are spaced away from each other; and wherein said concave segment shape is configured to be tuned towards said eye globe and configured to focalize said high intensity focused ultrasound beam in a straight line and generate an injury in a straight line, said straight line being perpendicular to said revolution axis of said eye ring for at least one transmission of said ultrasound beam.

2. A device according to claim 1 wherein said generator comprises a standing crown holding said transducers having a concave segment shape conformed along said unique curvature corresponding to said unique direction, said standing crown being fixed on said distal end of said eye ring in such a way that said transducers extend toward a revolution axis of said eye ring.

3. A device according to claim 2, wherein a width of each of said transducers is from 4.5 millimeters to 5 millimeters.

4. A device according to claim 1 wherein; said generator comprises a standing crown holding said transducers and at least two focusing acoustic elements extending under said respective transducers; each of said focusing acoustic elements has a concave segment shape conformed along said unique curvature corresponding to said unique direction; and said standing crown is fixed on said distal end of said eye ring in such a way that said focusing acoustic elements extend toward a revolution axis of said eye ring to focalize said high intensity focused ultrasound beam and generate injuries in said straight lines.

5. A device according to claim 4, wherein a width of each of said transducers is from 4.5 millimeters to 5 millimeters.

6. A device according to claim 4 wherein each of said transducers is a flat segment having a globally rectangular profile that extends sensibly parallel to said proximal and distal ends of said eye ring.

7. A device according to claim 1 wherein said concave segment shape is a cylindrical segment shape.

8. A device according to claim 1 wherein said concave segment shape is an elliptical segment shape.

9. A device according to claim 1, wherein said generator comprises a plurality of transducers arranged according to a treatment pattern.

10. A device according to claim 9, wherein said generator comprises a standing crown, said transducers being placed peripherally over said standing crown according to said treatment pattern.

11. A device according to claim 9, wherein said transducers are placed peripherally over a whole or a part of said standing crown.

12. A device according to claim 9, wherein said transducers are circumferentially placed over a whole or a part of a circumference of said standing crown.

13. A device for treatment of an ocular pathology comprising: at least one eye ring including a surface configured for direct placement onto an eye globe; and a high intensity focused ultrasound beam generator comprising multiple ultrasound transducers coupled to the eye ring, wherein the high intensity focused ultrasound beam generator presents a direction perpendicular to a revolution axis of said eye ring, where each of the transducers including a concave shape configured to face toward the eye, the transducers being elongated to outwardly radiate away from a central axis of the eye ring, and the transducers being spaced away from each other; the concave shape having a single curvature which is configured to focalize an ultrasound beam and configured to generate damage in a straight line, the straight line being parallel to a radial centerline of the single curvature.

14. A device according to claim 13 wherein the generator comprises a standing crown holding the transducers, the standing crown being fixed on a distal end of the eye ring such that the transducers extend toward the revolution axis of said eye ring.

15. A device according to claim 13 wherein the generator is elongated in a direction facing the eye globe.

16. A device according to claim 13, wherein a width of each of the transducers is from 4.5 millimeters to 5 millimeters.

17. A device according to claim 13 wherein the concave shape is a cylindrical shape.

18. A device according to claim 13 wherein the concave shape is an elliptical shape.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic perspective view of the device for treatment of an ocular pathology by applying a high intensity focused ultrasound according to the invention,

(2) FIG. 2 is an elevation view of the device according to the invention positioned to an eye to be treated,

(3) FIG. 3 is a partial view in elevation of the eye ring of the device according to the invention,

(4) FIG. 4 is a top view of the transducers held by the eye ring of the device according to the invention,

(5) FIG. 5 is a top view of the device correctly positioned to the eye to be treated,

(6) FIG. 6 is an elevation view of the device correctly positioned to the eye to be treated shown in FIG. 5,

(7) FIG. 7 is an elevation view of the device during the generation of HIFU energy,

(8) FIG. 8 is a 3D representation of the injured areas by HIFU energy according to the invention,

(9) FIG. 9 is an elevation view of another embodiment of the device according to the invention positioned to an eye to be treated,

(10) FIG. 10 is an elevation view of a last embodiment of device according to the invention particularly adapted for increasing the rate of transport of a drug through eye tissue,

(11) FIGS. 11 to 17 illustrate different embodiments of means to generate an ultrasound beam of the present invention.

DETAILED DESCRIPTION

(12) We will disclose hereinafter a method and a device suitable for the treatment of glaucoma; nevertheless, it is obvious that the skilled person could adapt the method and the device for the treatment of any ophthalmologic pathology that necessitate surgery without departing of the scope of the invention.

(13) Referring to FIG. 1, the device according to the invention comprises an eye ring 1, having a sawn-off cone shape, wherein the proximal end of said eye ring is suitable to be applied onto the globe of the eye to be treated and (see FIG. 2) means 2 to generate high intensity focused ultrasound energy, said means being fixed on the distal end of the eye ring. Said means are connected to a control unit 3 including a burst generator and means specifying the parameters of the burst such as the frequency, the power and the duration of each burst, the number of bursts (i.e. the number of transducers to be activated), etc. . . . . The burst generator comprises at least a sine-wave signal generator at a determined frequency comprised between 5 and 15 MHz, and preferably between 7 and 10 MHz, an amplifier and a Power meter.

(14) Referring to FIGS. 1 and 2, the eye ring 1 consists in a sawn-off cone element opened at both ends wherein the small base is the proximal end and the large base is the distal end.

(15) Referring to FIG. 2, the proximal end of the sawn-off cone shaped eye ring 1 comprises an external annular flange 4 suitable to be applied onto the external surface of the eyeglobe, at approximately 2 mm of the limbus, the limbs being the junction between the cornea and sclera of the eyeglobe. The proximal face of the annular flange 4 presents a concave profile, the radius of curvature of he concave profile being substantially equal to the radius of curvature of the eyeglobe.

(16) Moreover, the proximal edge of the sawn-off cone shaped eye ring 1 comprises an annular groove 5 connected to a suction device 6 (FIG. 1) by at least one hose 7 passing through the sawn-off cone shaped eye ring 1 and emerging into the annular groove, said suction device 6 being advantageously controlled by the control unit 3.

(17) It is obvious that the suction device 6 can be independent without departing from the scope of the invention.

(18) When the sawn-off cone shaped eye ring 1 is applied onto the eye and the suction device 6 is operated, the depression into the annular groove 5 provides a deformation of the conjunctiva of the eye, said deformation forming an o-ring in the annular groove 5. The sawn-off cone shaped eye ring 1 is then closely interlinked in such a manner that said sawn-off cone shaped eye ring 1 will follow the micro movements of the eye during the whole treatment time taking less than 2 minutes, and maintaining the quality of the centred position of the device on the visual axis.

(19) The sawn-off cone shaped eye ring 1 is advantageously obtained in medical grade silicon which is a soft material compatible with the conjunctiva contact.

(20) It is obvious that the sawn-off cone shaped eye ring 1 can be obtained in any suitable material for medical purposes well known by the skilled person, and which has been verified as biocompatible, such as biocompatible PVC, without departing with the scope of the invention.

(21) Referring to FIGS. 1 and 2, means 2 to generate a high intensity focused ultrasound beam consist in a standing crown 8 holding a plurality of transducers 9 wherein the external radius of said standing crown 8 is sensibly equal to the internal diameter of the distal end of the sawn-off cone shaped eye ring 1. The external edge of the standing crown 8 of transducers 9 comprises an annular groove 10 cooperating with an annular lug 11 extending in the sawn-off cone shaped eye ring 1 at the vicinity of it's distal end in such a way that he standing crown 8 is retained at the distal end of the sawn-off cone shaped eye ring 1. In this way, the standing crown 8 extends toward the revolution axis of said sawn-off cone shaped eye ring 1. Said transducers 9 are held in the proximal edge of the standing crown 8. Moreover, each transducer 9 is a segment having a concave profile, wherein the concavity is tuned towards the eyeglobe, and more particularly towards the ciliary body as shown in FIG. 2. The proximal edge of the standing crown 8 comprises an annular groove 12 in which extends the connecting cables of the transducers 9, not shown in FIG. 2.

(22) The transducers can be made either in piezocomposite material or in piezoceramic material or in other materials which complies with the production of the High Intensity Ultrasound. Said transducers can be focused by themselves and have a toric geometry, or a cylindrical geometry or a spherical geometry, or an elliptical geometry.

(23) As shown on FIG. 11, the use of transducers 9 having a toric shape allows obtaining a lesion volume 49 having a shape of an arc of circle which corresponds to the annular shape of the ciliary body 50.

(24) As shown on FIG. 12a, the radial radiuses 51 of curvature of transducers 9 having a toric geometry are all identical.

(25) However, as shown on FIG. 12b, the concentric radiuses 52 of curvature of transducers 9 having a toric geometry are all different.

(26) This implies that the ultrasound beams generated by the transducers 9 may focus on two different regions 53, 54 due to the two radiuses of curvature 51, 52 of the toric shape (see FIGS. 13a, 13b).

(27) To overcome this drawback, transducers 9 having a geometry presenting a single radius of curvature 51 are preferred (see FIG. 14).

(28) More precisely, the transducers 9 preferably present a concave segment shape conformed along a single curvature corresponding to a single direction 55 wherein the concavity is designed to be tuned towards the eyeglobe.

(29) As shown on FIG. 15, the lesion 49 obtained using transducers 9 having a single radius of curvature 51 is not an arc of a circle anymore, but a line segment. This line segment is inscribed in the annular shape of the ciliary body 50.

(30) Preferably, the single direction is perpendicular to the revolution axis of the eye ring. This allows obtaining a lesion volume conformed along a line segment parallel to the ciliary body.

(31) It has to be noticed that a transducer having a toric trapezoidal segment shape, due to a greater active surface, presents better conversion efficiency than a transducer having a rectangular geometry presenting a single radius of curvature. For a given electrical power, the acoustic power concentrated on a focal line is greater with a transducer having a toric segment shape than with a transducer having a geometry presenting a single radius of curvature. To overcome this drawback, the length of transducers having a geometry presenting a single radius of curvature is chosen greater than the length of corresponding transducers having a toric segment shape.

(32) Each transducer can be made of a single segment curved along a single curvature corresponding to a single direction a single radius of curvature so as to define the concave segment shape of the transducer.

(33) The transducers 9 can be flat and be used in combination with a focusing system like acoustic lens or acoustic reflectors, with a variety of Shapes and materials, extending under or in front of said flat annular transducers. Acoustic reflectors are well known in therapeutic ultrasound and are currently routinely used in external shockwave lithotripsy (Focusing water shock waves for lithotripsy by various ellipsoid reflectorsMller M.Biomed Tech (Berl). 1989 April; 34(4):62-72).

(34) In this case, the acoustic reflectors preferably have a geometry presenting a single radius of curvature for the reason explained above.

(35) Referring to FIGS. 4 and 17, the standing crown 8 of transducers 9 comprises two pairs of three transducers 9 separated by two inactive sectors 13. Each transducer 9 is a cylindrical segment able to treat 44 of the circumference of the ciliary body, with an internal diameter of 12.8 mm and an external diameter of 27 mm.

(36) The inactive sectors 13 correspond to two zones of the eye (called the naso-temporal axis zones) comprising nerve terminations and vascularisations. Thus the arrangement of transducers of the present invention allows avoiding the treatment of these zones.

(37) It will be understood that the dimensions and arrangement of the transducers is a function of the diameter of the eye to be treated and of the size of the ciliary body (which differ from one type of animal to the other). The dimensions of each transducer are defined so as to obtain a lesion volume comprised between 3 mm.sup.3 and 6 mm.sup.3. The dimensions of the lesions obtained with each transducer can be calculated using simulation software developed by INSERM U556 on the basis of the Bio Heat Transfer Equation.

(38) The transducers of a pair can be separated by 0.2 mm from each other along the internal diameter. The width of each transducer is less than 5 mm, and preferably equal to 4.5 mm. The length of each transducer 9 can be comprised between 7 mm and 9 mm, and preferably equal to 8.1 mm. The radial radius of curvature of each transducer 9 can be comprised between 9 mm and 11 mm, and preferably equal to 10.2 mm. The thickness of each transducer can be comprised between 0.1 mm and 0.4 mm and is preferably equal to 0.25 mm. For a piezoceramic transducer with a nominal frequency of 7 MHz, it will be used at its third harmonic. It will be noted that the standing crown 8 can comprise two or more transducers 9 distributed among the circumference in any manner without departing with the scope of the invention.

(39) The transducers 9 are successively activated by the control unit 3 to destroy the ciliary body over the whole or a part of its circumference, each transducer 9 providing an internal injury in a shape compatible with the shape of the ciliary bodies of an arc of circle (i.e. lesions in the form of straight lines within an octagon).

(40) In this embodiment, adapted to the treatment of glaucoma, the internal diameter of the proximal end of the sawn-off cone shaped eye ring 1 is sensibly equal to the corneal diameter plus 2 to 6 mm

(41) The internal diameter of the proximal end of the sawn-off cone shaped eye ring 1, depending on the patient corneal diameter, is comprised between 12 and 18 mm and the internal diameter of the distal end of the sawn-off cone element is comprised between 26 and 34 mm.

(42) Moreover, the height of the sawn-off cone shaped eye ring 1 is comprised between 8 and 12 mm. In this manner, by positioning correctly the sawn-off cone shaped eye ring 1 onto the eye to be treated, as described hereinafter, the whole or a part of the ciliary body of the eye will be injured by HIFU energy without the need to manipulate the device during the treatment.

(43) To apply correctly the sawn-off cone shaped eye ring 1 onto the eye, referring to FIG. 5, the surgeon must manipulate the sawn-off cone shaped eye ring 1 as far as the iris ring and the periphery of the cornea are centred in the distal opening of the sawn-off cone shaped eye ring 1 as illustrated in FIG. 5. If the white ring corresponding to the visible part of the sclera trough the opening of the proximal end of the ring, has a constant thickness, the centering is correct. When the sawn-off cone shaped eye ring 1 is centred on the pupil, the revolution axis of said sawn-off cone shaped eye ring 1 and the optical axis of the eye are merging, referring to FIG. 6. Consequently, the planes in which extend the distal edge and the proximal edge of the sawn-off cone shaped eye ring 1 are perfectly parallel to the planes of the eye such as iris plane, pupil plane or plane of the ciliary body, and the proximal edge of the sawn-off cone shaped eye ring 1 is at the plumb of the ciliary body. This allows a better positioning of the device according to the invention with regard to the lesions obtained (unlike the apparatus described in U.S. Pat. No. 4,484,569 and DE 44 30 720), and improves the reproducibility of the treatment.

(44) Moreover, the device can comprise two aiming wires 14 extending crosswise and diametrally from the internal edge of the standing crown 8 or another centering system like a circular pad supposed to be centred on the pupil. This allows facilitating the centering of the sawn-off cone element with regard to the eye. To centre the sawn-off cone shaped eye ring 1, it is necessary to, centre the intersection of the aiming wires 14 with the centre of the pupil.

(45) It will be understood that the device according to the invention can comprise other centering system known from the man skilled in the art for facilitating the centering of the sawn of cone.

(46) When the sawn-off cone shaped eye ring 1 is correctly centred onto the eye, the suction device 6 is activated to interlink said sawn-off cone shaped eye ring 1 with the eye. The depression into the annular groove 5 provides a deformation of the conjunctiva of the eye, said deformation forming an o-ring in the annular groove 5. This insures a proper maintain in position of the device during all the treatment.

(47) The sawn-off cone shaped eye ring 1 is then filled with a physiological saline degassed solution, referring to FIG. 7, the o-ring formed by the deformation of the conjunctiva of the eye in the annular groove ensuring the sealing. The physiological saline solution provides a cooling of the eye and the device during the generation of HIFU and an ultrasound coupling media that permits the propagation of ultrasound from transducers 9 to area of interest, i.e. the ciliary body. Note that the physiological saline solution moisturizes the cornea of the eye during the treatment.

(48) It is obvious that the physiological saline degassed solution could be substituted by any ultrasound coupling agent such as aqueous media or lipophilic media without departing of the scope of the invention.

(49) Then, the frequency and/or the power and/or the duration of each pulse are selected or already predetermined and the transducers 9 are successively activated by the control unit to destroy the ciliary body over the whole or a part of the circumference. Preferably, each transducer is elongated so that each transducer provides an internal injury in the shape of straight lines or arc of circle as represented in FIG. 8. Note that, in FIG. 8, the X-Y plane represents the free end of the eyeglobe and that the height represents the depth of the eye globe. The use of elongated transducers allows producing unpunctual lesions more extended than the punctual lesions obtained with the apparatuses described in U.S. Pat. No. 4,484,569 and DE 44 30 720. This improves the efficiency of the treatment sine less non-destroyed tissues remain (with regard to results obtained with the apparatuses described in U.S. Pat. No. 4,484,569 and DE 44 30 720).

(50) Note that the treatment according to the invention is advantageously an ambulatory treatment whose duration is about 2 minutes for the patient

(51) According to another embodiment of the invention, referring to FIG. 9, the device comprises in the same manner as preceding a sawn-off cone shaped eye ring 1 opened at both ends wherein the small base is the proximal end and the large base is the distal end and means 2 to generate a high intensity focused ultrasound beam, said means being fixed on the distal end of the sawn-off cone shaped eye ring 1. Said means 2 consist in a standing crown 8 holding a plurality of transducers 9 wherein the external radius of said standing crown 8 is sensibly equal to the internal diameter of the distal end of the sawn-off cone shaped eye ring 1. The external edge of the standing crown 8 of transducers 9 comprises an annular groove 10 cooperating with an annular lug 11 extending in the sawn-off cone shaped eye ring 1 at the vicinity of it's distal end in such a way that the standing crown 8 is retained at the distal end of the sawn-off cone shaped eye ring 1. In this way, the standing crown 8 extends toward the revolution axis of said sawn-off cone shaped eye ring 1.

(52) Said transducers 9 are held in the proximal edge of the standing crown 8. Moreover, each transducer 9 is a flat segment having a globally rectangular profile that extends sensibly parallel to the proximal and distal edge of the sawn-off cone shaped eye ring 1.

(53) Moreover, the device comprises a focusing acoustic lens 15 extending under said transducers 9, i.e. held by the standing crown 8 and extending between the proximal edge of the standing crown 8 and the proximal edge of the sawn-off cone shaped eye ring 1. Said focusing acoustic lens presents a cylindrical shape and a concave edge wherein the concavity is tuned towards the eyeglobe, and more particularly towards the ciliary body as shown in FIG. 9, to focalize HIFU onto the area of interest, i.e. the ciliary body of the eye.

(54) The standing crown 8 comprises an annular channel 16 in which extends the connecting cables of the transducers 9, not shown in FIG. 9.

(55) As disclosed previously, referring to FIG. 4, the standing crown 8 of transducers 9 comprises two pairs of three transducers 9 separated by two inactive sectors 13. Each transducer 9 is an annular segment of 44 with an internal diameter of 12.8 mm and an external diameter of 24.3 mm.

(56) It is obvious that means to generate high intensity focused ultrasound energy can consist in at least two transducers having a cylindrical segment shape, fixed on the distal end of the sawn-off cone element in such a way that said transducers extend toward the revolution axis of said sawn-off cone element.

(57) Moreover, said means to generate high intensity focused ultrasound energy can be substituted by means to generate high intensity dynamically focused ultrasound energy consisting in at least two annular array transducers having a toric segment shape, fixed on the distal end of the sawn-off cone element in such a way that said annular array transducers extend toward the revolution axis of said sawn-off cone element.

(58) The device according to the invention can be used for treatment of open angle glaucoma, but with a different approach than cyclodestruction. Indeed as described in WO 2008/024795, ultrasound can be used for their vibrating properties on small particles. In patients with too high intra ocular pressure, and with open angle glaucoma, the problem is that the trabecular meshwork is no longer efficient enough to allow aqueous humor to be drained properly to Schlemm's canal. Trabeculum permeability is lower than normally, due to the fact that trabecular spaces are blocked with small particles as pigments, cell debris, fibrin, etc. . . . .

(59) The device according to the invention can easily produce a vibration obtained with the propagation of an ultrasonic beam, transmitted to the trabecular meshwork, which unlike the apparatus described in WO 2008/024795 can concern the whole circumference of the trabeculum at the same time, more rapidly and in only one step. Moreover, with the device according to the invention, thanks to the ring which allows centering and fixation on the eye globe, this technique can be substantially improved compared to the device described in WO 2008/24795.

(60) In the case where the device according to the invention is used to produce vibration, the power is lower and the duration of the energy generated by each transducer is shorter than previously explained, and is repeated periodically with many successive bursts. For instance, the duration of the energy generated by each annular transducer is less than 10 seconds, and more preferably less than 5 seconds, the application of is repeated 2 times or more.

(61) Indeed, in such case, the aim is no longer to produce lesions (i.e. destroy the target region as explained with reference to the ciliary bodies) but to produce vibration. So it is necessary to limit the duration of the energy generated in order to ensure that the target region (i.e. the trabeculum in the present case) is not burned.

(62) Another embodiment of the device according to the invention, used as a treatment of open angle glaucoma with the vibration technique applied on the trabecular meshwork, can be combined with a phacoemulsification machine. In fact when the particles like cell debris, fibrin, pigment or other, responsible for the loss of drainage efficiency of trabeculum, are delivered from their adherence to the trabecular meshwork, and are circulating in the aqueous humor it is Obvious that they will rapidly be cached again by trabeculum, reducing consequently the efficiency of the treatment by the vibration technique. The idea for this preferred embodiment, is to combine this treatment with a phacoemulsification Machine, and preferably during a cataract surgery, because during this surgery the anterior chamber and the liquid it contains, are completely washed with a balanced salt solution circulating in the irrigation/aspiration circuit, so that if the vibration technique is performed before the cataract surgery, all the debris delivered from their adherence on the trabecular meshwork, will be washed out of the anterior chamber, increasing the efficiency of the treatment. It is well known that cataract surgery is more frequent in older population. It is well known too that glaucoma is more frequent in the same population. For this reason, combined surgeries, including cataract and trabeculectomy are more and more frequent. The idea for this preferred embodiment, is to add a new feature to the phacoemulsification machines, already often equipped with vitrectomy features, which will be the glaucoma prevention by a systematic cleaning of the trabeculum with the ultrasound vibration technique, when a cataract surgery is performed in a patient with a too high intra ocular pressure (>15-18 mm Hg).

(63) It is obvious that the device according to the invention could be adapted for other ocular pathology such as for a cataract surgery by focusing the HIFU onto the crystalline lens rather than onto the ciliary body.

(64) The goal of the cataract surgery is to replace the natural crystalline lens by an artificial lens, when the natural crystalline lens has lost its transparency. In a first step, it is necessary to remove the natural lens surgically. According to the prior art, this extraction is performed by a phacoemulsification procedure. The surgeon uses a machine equipped with an ultrasonic hand piece. The tip of the hand piece sculpts the crystalline lens and simultaneously irrigates and sucks the lens debris.

(65) By adapting the device according to the invention by focusing the HIFU onto the crystalline lens rather than onto the ciliary body, the cataract surgery by a phacoemulsification procedure could be made easier, faster and more accurate. The device could be used advantageously before the surgery to modify the consistence of the crystalline lens and to reduce the adherence between the cortex and the capsular bag. This could be done in order to: reduce the dimension of the corneal incision, reduce the duration of the surgery and increase the quality of the extraction by reducing the quantity of residual cortex, which is responsible for postoperative capsular bag opacification.

(66) According to a last embodiment of the invention particularly adapted to facilitate penetration of pharmaceutical agents in the eye, referring to FIG. 10, the device comprises in the same manner as preceding a sawn-off cone element 1 opened at both ends wherein the small base is the proximal end and the large base is the distal end and means 9 to generate a scattered ultrasound beam, said means being fixed on the distal end of the sawn-off cone shaped eye ring 1.

(67) Such a technique as described in WO 2007/081750, could be particularly useful to avoid intra vitreal injection of pharmaceutical agents, for treating chronic or acute eye diseases. But the cited invention doesn't describe a device adapted to the eye globe intended to facilitate the manipulation, and with a large area surface covered by high intensity ultrasound. The present embodiment of the invention as described above, could facilitate the manipulation with the use of a centering and fixation ring, and increase the efficacy of the treatment thanks to as larger area covered by the ultrasound beam.

(68) Said means 17 consist in a standing crown 8 holding a plurality of transducers 9 wherein the external radius of said standing crown 8 is sensibly equal to the internal diameter of the distal end of the sawn-off cone shaped eye ring 1. The external edge of the standing crown 8 of transducers 9 comprises an annular groove 10 cooperating with an annular lug 11 extending in the sawn-off cone element 1 at the vicinity of it's distal end in such a way that the standing crown 8 is retained at the distal end of the sawn-off cone shaped eye ring 1. In this way, the standing crown 8 extends toward the revolution axis of said sawn-off cone shaped eye ring 1.

(69) Said transducers 9 are held in the proximal edge of the standing crown 8. Moreover, each transducer 9 is an annular segment suitable to generate a scattered ultrasound beam into the sawn-off cone shaped eye ring 1, said sawn-off cone shaped eye ring 1 being filed with a coupling media 18 such as physiological saline degassed solution containing a pharmaceutical formulation and/or micro carriers.

(70) In this non limited example, said transducers 9 has a globally rectangular profile that are inclined globally toward the centre of the proximal edge of the sawn-off cone shaped eye ring 1.

(71) It is obvious that means to generate a scattered ultrasound beam can be means to generate high intensity non focused ultrasound energy consisting in at least two transducers having an annular or rectangular flat segment shape, fixed on the distal end of the sawn-off cone element in such a way that said transducers extend toward the revolution axis of said sawn-off cone shaped eye ring 1.

(72) Said transducers 9 are circumferentially placed over the whole orb part of the circumference of the standing crown 8.

(73) When the sawn-off cone shaped eye ring 1 is applied onto the eye, the iris ring and the cornea perimeter are globally centred in the distal opining of the sawn-off cone shaped eye ring 1. Then, the suction device 6 is activated to interlink said sawn-off cone shaped eye ring 1 with the eye. The depression into the annular groove 5 provides a deformation of the conjunctiva of the eye, said deformation forming an o-ring in the annular groove 5.

(74) The sawn-off cone shaped eye ring 1 is then filled with a physiological saline degassed solution containing the appropriate pharmaceutical agents, the o-ring formed by the deformation of the conjunctiva of the eye in the annular groove ensuring the sealing.

(75) Then, the frequency and/or the power and/or the duration of pulses are selected or already predetermined and the transducers 9 are successively or simultaneously activated by the control unit to increase the porosity of the cornea and of the sclera of the eye and to homogenise the pharmaceutical agent in the coupling media, by mixing it, that enhance the transport rate of the pharmaceutical agents across the cornea an scleral tissues reaching the anterior and posterior segments of the eye and avoiding intra ocular injections.

(76) Note that the device according to the invention could be used in case of any medical treatment of eye diseases with local drug administration. Usually this kind of treatment is administered topically with eye drops. The problem is that eye drops must be administered many times per day, which is a constraint and often leads to the patient's demotivation, even if new drugs formulations have recently reduced in some cases to once a day the number of eye drops administrations. Other kinds of treatments require intra-vitreal injections of the drugs directly in the eye.

(77) Using high intensity ultrasound to facilitate drug penetration in biologic tissues according to the invention leads to increased action duration, a reduction of the doses administered and a better efficacy.

(78) The device according to the invention could be used for example to avoid intra-vitreal injections of antibiotics, anti viral drugs, anti inflammatory drugs, chemotherapy agents or new molecules like anti-angiogenics for the treatment of diabetic macular edema or of age related macular degeneration. The intra-vitreal injections are of potential high risk. The geometric shape of our device could allow its filling with a liquid containing an active drug. A particular model of the device designed to produce a non focused ultrasound beam, with a low power which doesn't generate lesions in the tissues could allow the penetration of active drugs in the intraocular structures.

(79) Moreover, note that the standing crown 8 holding means 9 to generate a scattered ultrasound beam is advantageously removable and can be substituted by a standing crown 8 holding means 2 to generate HIFU beam as disclosed in FIGS. 2 and 9.

(80) This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The scope of the subject matter described herein is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.