Coupling interface between the laser source and the treated tissue

Abstract

The invention relates to a coupling interface between a laser source and tissue to be treated, characterized in that it comprises a ring (3) and a gel block (4), said ring (3) having a double-walled partition (31) and a window (33) transparent to the laser beam generated by the laser source, said window (33) being sealingly attached to the distal end of the ring so as to close said distal end, said gel block (4) being intended to be placed in the working housing of the ring.

Description

[Technical field]

[0001] The present invention relates to the technical field of surgery performed by lasers, and more particularly to the field of ophthalmic surgery, especially for the application of incisions in the cornea or the lens.

[0002] The present invention relates to a compatible interface for coupling a laser source to human or animal treated tissue, such as the cornea or lens.

[0003] By laser source is meant a light source capable of emitting a laser beam in the form of ultrashort pulses having a duration between 1 femtosecond and 100 picoseconds, preferably between 1 femtosecond and 1000 femtoseconds, in particular of the order of 100 femtoseconds. [Background technology]

[0004] It is well known in the state of the art to perform eye surgery, such as corneal or crystalline lens incision surgery, using a laser source.

[0005] A laser source is an instrument that can incise corneal tissue, for example, by focusing a laser beam on the corneal stroma, creating a series of adjacent small cavitation bubbles, and forming an incision line.

[0006] More precisely, during focusing of the laser beam on the cornea, when the intensity of the laser source exceeds a threshold called the optical destruction threshold, a plasma is generated by nonlinear ionization. Cavitation bubbles are then formed, which cause very localized destruction of the surrounding tissue. Thus, the volume actually removed by the laser source is very small compared to the destroyed area.

[0007] In order to couple a laser source to a patient's eye, it is known to use a conformal interface disposed between the patient's eye and the laser source.

[0008] Such a coupling interface allows to keep the eye in a stable and constant position, central and at a known distance from the laser source, avoiding any movement during the treatment.

[0009] 1. Coupling interfaces known in the prior art 1.1. First example of an existing coupling interface 1.1.1. General Description Figure 1 shows a first example of a coupling interface of the prior art. The coupling interface comprises a ring including a truncated cone 1 with an axis A-A'. The truncated cone 1 is open at both ends. The large base 11 of the truncated cone 1 is intended to receive the end of a laser source. The small base of the truncated cone 1 is intended to contact the eye 2. The coupling interface also includes: - an annular gas flow groove 12 extending around the periphery of the small base; a tubular access member 122 extending radially outwardly and enabling the annular groove 12 to be connected via a connecting nozzle 123 to an external suction device (not shown).

[0010] The annular groove 12 has a U-shaped cross section defined by two circular rims 124, 125 intended to be pressed against the patient's eye 2. Suction devices, as such known to the person skilled in the art, are capable of creating a vacuum in the annular groove 12 when the circular rims 124, 125 are applied to the eye 2. The generation of a vacuum in the annular groove 12 allows the coupling interface to be fixed on the eye 2 by a suction effect that lasts the entire duration of the treatment.

[0011] 1.1.2. Working principle of the first example of an existing coupling interface The principle of operation of such a coupling interface is as follows.

[0012] First, the practitioner places the ring of the coupling interface on the eye 2 .

[0013] Once the ring is correctly positioned and centered, the suction device is activated to create a vacuum in the space defined between the annular groove 12 and the eye 2, securing the coupling interface on the eye 2 by suction.

[0014] Once the ring is fixed on the eye 2, the cone 1 is filled with a liquid having a refractive index close to that of the cornea until the cornea is bathed. The liquid bathing the cornea in this way has the advantage of simplifying the trajectory of the laser beam through the cornea by optically eliminating the diopter of the cornea.

[0015] The laser source is then positioned over the coupling interface and a distal portion of the laser source is inserted and locked into the coupling interface to ensure that the eye 2 and the optical axis of the laser are aligned and maintained securely for the duration of the treatment.

[0016] 1.1.3. Disadvantages of the first example of existing coupling interfaces Such coupling interfaces have a number of drawbacks.

[0017] 1.1.3.1. Pressure applied to the interface to ensure a seal The efficiency of suction of the coupling interface on the eye 2 depends on the quality of the seal between the circular rims 124 , 125 and the eye 2 .

[0018] Therefore, complete contact must be obtained all around the contact line of each circular rim 124,125.

[0019] This is not necessarily simple as every patient's eye is different and the surface of the eye does not necessarily follow the slope between each of the circular rims 124,125.

[0020] Therefore, to overcome such non-uniformities in the patient's eye, the ring of the coupling interface must be pressed hard to obtain a good seal between the groove 12 and the eye 2, which compromises the comfort and safety of the patient. Indeed, the force applied to the ring of the coupling interface to obtain an adequate seal tends to drive the circular rims 124, 125 into the conjunctiva.

[0021] The force applied to achieve a seal is sometimes so great that patient discomfort tends to be painful. Moreover, this pressure, even for a short period of time, can quickly increase the patient's intraocular pressure, potentially causing serious side effects in some at-risk patients (those with high myopia, a history of retinal detachment, or glaucoma).

[0022] 1.1.3.2. Vacuum Level A large level of vacuum must be applied to hold the coupling interface in place.

[0023] Indeed, the suction force must be large to resist micro-movements of the eye and its tendency to release the suction.

[0024] However, it is known that the suction force F is a function of the vacuum P and the surface S to which this vacuum is applied, i.e.: F=P×S

[0025] In conventional coupling interfaces, the surface area to which the vacuum is applied is small (i.e., limited to the surface of the eye between the two circular rims) and a significant value of vacuum must be applied to obtain a suction force F that can resist small movements of the eye and the tendency of the suction to release.

[0026] The importance of the applied vacuum sometimes leads to the appearance of conjunctival hemorrhage (exudation of red blood cells associated with subconjunctival suction). Although superficial ecchymoses are generally very limited and do not affect vision, they are always a concern for the patient and very unattractive, so it is desirable to limit their appearance.

[0027] 1.1.3.3. cost Some conventional coupling interfaces work with special surgical equipment. These have to integrate the suction system with pumps, nozzles and vacuum sensors. As each system is special, all these accessories have to be purchased. The present invention avoids such unnecessary expenses. In fact, this patient interface works with accessories already present in the operating room, in particular with phacoemulsification machines. The latter are equipped with a suction pump with vacuum sensor and an infusion line and already have sufficient nozzles. The inventors' experimental tests show that the novel coupling interface, the object of the present invention, works perfectly with phacoemulsification machines and brings substantial savings to the customer.

[0028] 1.2. Second example of an existing coupling interface In order to overcome the aforementioned shortcomings, WO2018154038 proposes a coupling interface, which includes: - a ring including a sidewall, a proximal end for contacting the tissue to be treated, and a distal end for receiving an end of a laser source; - a window transparent to the laser beam generated by the laser source, the window being hermetically mounted on the ring so as to close the distal end of the ring; - a suction through-channel extending between the inner and outer surfaces of the side wall, the suction channel being intended to be connected to a suction module for generating a vacuum in an interior space defined between the window, the side wall and the upper part of the eye; - a perfusion through-channel extending between the inner and outer faces of the side wall, the perfusion through-channel intended to be connected to a perfusion module to allow the injection of liquid into the interior space.

[0029] By generating a vacuum throughout the entire internal space of the coupling interface, the surface area over which the vacuum acts is significantly increased compared to the coupling interface shown in Figure 1, where the vacuum is only applied to the circular rim. This allows a lower vacuum level to be applied to the eye, helping to reduce side effects caused by too high a vacuum. The coupling operation is more comfortable for the patient.

[0030] While this interface has many advantages, the patient's eye may move by anywhere from a micron to tens of microns, but when making certain incisions it is desirable for the cornea to remain completely fixed.

[0031] DE 10 2005 040338 describes an adapter for mechanically coupling a laser therapy device to a patient's eye. The adapter described in DE 10 2005 040338 comprises a glass lens body having a lower surface adapted to the curvature of the human cornea and a holder surrounding this lens body.

[0032] WO2019 / 104256 describes a patient interface for an adjustable intraocular lens illumination system.

[0033] The object of the present invention is to provide a novel coupling interface that has the same advantages as the coupling interface described in WO2018154038 and allows complete fixation of the patient's eye (less than 10 microns of ocular movement). Summary of the Invention

[0034] To this end, the present invention provides a coupling interface between a laser source and tissue to be treated, said coupling interface comprising: - a ring having a proximal end for contacting the tissue to be treated and an opposite distal end; and - Gel Block Equipped with The ring is A double-walled partition (31), the double-walled partition (31) ■ an inner (cylindrical) side wall having an upper end and a lower end; and ■ an outer (cylindrical) side wall having an upper end and a lower end; a double-walled partition, wherein a lower end of the inner sidewall is closer to the distal end than a lower end of the outer sidewall, and each upper end of the inner sidewall and each upper end of the outer sidewall are closer to the distal end than each lower end of the inner sidewall and each lower end of the outer sidewall; a perforated disk between the lower ends of the inner and outer sidewalls and including a bore therethrough; a window transparent to a laser beam produced by the laser source, the window being sealingly attached to each of the upper ends of the inner and outer side walls so as to close a distal end of the ring; a suction chamber around the perforated disk, the inner sidewall and the outer sidewall; ■ An action housing located at the center of the inner side wall and a window; and a suction channel extending between the inner and outer surfaces of the outer side wall so as to open into a suction chamber (between the inner and outer walls), the suction channel being intended to be connected to a suction module for generating a vacuum in an interior space defined between the suction chamber and the suction channel; and The gel block is intended to be placed in a working housing and comprises: · A side flank having a shape complementary to the shape of the inner sidewall and intended to contact the inner surface of the inner sidewall; · a substantially flat circular upper base intended to be in contact with the window; A circular, concave lower base that is intended to come into contact with the tissue to be treated It includes, The present invention proposes a coupling interface characterized by:

[0035] The gel block is advantageously removably mounted within the working housing. Furthermore, the gel block is slidable along the inner sidewall of the double-walled partition. Furthermore, the gel block is deformable.

[0036] The above-described coupling interface differs from existing interfaces, inter alia, in that it includes a ring including a double-walled partition, a window attached to an upper end of the double-walled partition, an operating housing bounded by the window and an inner sidewall of the double-walled partition, and a gel block removably mounted within the operating housing.

[0037] The combination of these features makes it possible to have a coupling interface which adapts to the shape of the patient's eye, unlike, for example, the adapter described in DE 10 200 5040 338 (which proposes the use of a glass lens body) where it is the patient's eye which is deformed (through the application of a large bearing force) to adapt to the shape of the underside of the glass lens body.

[0038] The use of gel blocks reduces the risk of the patient's eye moving during surgery. In fact, the friction coefficient of the interface between the eye and the gel block is greater than that of the interface between the eye and a liquid with a refractive index close to that of the cornea as proposed in WO2018154038. The use of gel blocks also reduces the risk of the cornea moving vertically (hydrogels limit vertical movement more than liquids). This is very important for non-penetrating corneal incisions (such as arcuate incisions for astigmatism correction).

[0039] However, the present invention is not limited to replacing the coupling liquid with a gel block. Indeed, in order to benefit from the advantages associated with the device described in WO2018154038, the inventors had to rethink the entire structure of the coupling interface according to WO2018154038.

[0040] In particular, the presence of the double-walled partition makes it possible to prevent the gel block from being aspirated through the suction channel, and also ensures that the gel block is centered when the patient interface is applied.

[0041] Moreover, the combination of the double-walled partition and the gel block allows to reduce the discomfort of the patient compared to the prior art solutions as shown in Fig. 1. Indeed, in the interface shown in Fig. 1, two circular rims 124, 125 (i.e. the inner rim 124 and the outer rim 125) are intended to contact the patient's eye, which requires the practitioner to press hard on the ring to ensure full contact between the patient's eye and each of these circular rims 124, 125. In the present invention, the gel block replaces the inner rim. Thus, the double-walled partition has a single rim intended to contact the patient's eye, - The deformability of the gel block ensures perfect contact between the gel block and the patient's eye, - perfect contact between the single rim of the double-walled partition and the patient's eye does not require the user to apply large bearing forces (it is easier to obtain perfect contact between the eye and a single circular rim (principle of the ring on a sphere where 360° contact is always obtained) rather than between the eye and two concentric rims as proposed in the prior art patient interface shown in Figure 1).

[0042] More specifically, to set the patient interface shown in Figure 1, it is the patient's eye that is deformed (through application of a large bearing force) to conform to the shape of the patient interface. Conversely, in accordance with the solution of the present invention, it is the patient interface that conforms to the shape of the patient's eye by using: - A double-walled partition with a single rim that contacts the patient's eyes; - Deformable movable gel block.

[0043] Such a coupling interface allows for fast and painless aspiration while ensuring immobility of the patient's eye. This coupling interface is compatible with the use of an aspiration module that can be integrated into devices commonly found in ophthalmic operating rooms, i.e. phacoemulsification devices or other aspiration modules with sufficient performance and the necessary sensors. Of course, the invention is also compatible with the use of non-integrated aspiration modules.

[0044] Several models can be provided as the gel block, with the concave circular lower base of each gel block model having a radius of curvature that is different from the radius of curvature of the concave circular lower base of the other gel block models.

[0045] actual: - The gel block has limited deformability (elastic modulus between 0.1 and 1 MPa), - Eye size varies from patient to patient. It would be advantageous to have several models of the gel block in order to optimally fit the gel block to all eye sizes without having to constrain the patient's eye.

[0046] For this reason, we developed three gel block models: - the first model of a gel block with a circular concave lower base with a radius of curvature of 7.1 mm, - a second model of a gel block with a circular concave lower base with a radius of curvature of 7.6 mm, - The third model of the gel block with a circular concave lower base with a radius of curvature of 8.1 mm.

[0047] Of course, the reader will appreciate that more (or less) than three gel block models may be provided, and in either case, the practitioner may select the gel block model that is most suitable for a particular patient based on standard preoperative eye measurements.

[0048] Preferred, non-limiting aspects of the coupling interface are as follows: - the gel block may be made of a material having an elastic modulus between 0.1 and 1 MPa; - The height of the gel block may be substantially equal to the height of the inner side wall of the double-walled partition; - the double-walled partition and the gel block may be cylindrical in shape, the diameter of the gel block being substantially equal to the diameter of the inner side wall of the double-walled partition, for example between 11 and 14 millimeters; The lower base of the gel block may be concave, and the distance between the upper base and the lower base may be - in the range of 1 to 2.5 millimeters at the center of the lower base, · substantially equal to 4.5 and 6 millimeters around the lower base; - the lower base of the gel block may be concave, and the radius of curvature of the lower base is between 6.5 and 8.5 millimeters; - the height of the outer side wall may be greater than the height of the inner side wall such that the lower end of the inner side wall is closer to the window than the lower end of the outer side wall, and a perforated disk connecting each lower end of the inner side wall and the outer side wall has a substantially frustoconical shape such that the axis of the lumen is oriented along the longitudinal axis of the ring; - the surface area of ​​the perforated disc that is covered by the through-bore may be greater than the surface area of ​​the perforated disc that is not covered by the through-bore; - the ring may further include a frusto-conical flange open at the rim of maximum diameter, the flange being connected to the upper end of the outer sidewall by the rim of minimum diameter; - the ring may further have an annular collar integral with the rim of maximum diameter, the collar extending radially outwardly and including a flexible rubber layer on a surface thereof opposite the flange; The double wall partition, the flange and the annular flange may be integral.

[0049] The present invention also relates to a method of providing a coupling interface between a laser source and tissue to be treated, comprising: The coupling interface is - A ring: Double-walled partitions with an inner side wall and an outer side wall, a perforated disk between the lower ends of the inner and outer side walls; a window for transmitting a laser beam attached to each of the upper ends of the inner side wall and the outer side wall; a ring, wherein the inner and outer side walls, the perforated disk, and the window define a suction chamber of the ring, and the window and the inner side wall define a working housing of the ring; a gel block including a side flank, an upper base, and a lower base; The method comprises the steps of: - inserting the gel block into the working housing; - placing (centering) the ring containing the gel block over the tissue to be treated; - contacting, contacting the tissue to be treated with a lower end of the outer sidewall in a peripheral area of ​​the tissue to be treated; and contacting the tissue to be treated with a lower base of the gel block at a central region of the tissue to be treated; - activating a suction device to create a vacuum in a suction chamber between the inner side wall of the ring and the side flank of the gel block; - deactivating the suction device as soon as the desired vacuum threshold is reached; - A process that maintains a constant vacuum throughout the entire treatment period.

[0050] Once treatment is complete, the coupling interface is separated from the treated tissue by restoring atmospheric pressure in the suction chamber. [Brief description of the drawings]

[0051] Other characteristics and advantages of the present invention will become clearly apparent from the following description, given for illustrative and non-limiting purposes with reference to the attached figures, in which: [Figure 1]FIG. 1 is a schematic diagram of a prior art coupling interface. [Diagram 2] FIG. 2 is a schematic diagram of a coupling interface according to the present invention. [Diagram 3] FIG. 3 is a schematic diagram of a coupling interface according to the present invention. [Figure 4] FIG. 4 shows a method of mounting a coupling interface according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] The coupling interface according to the invention will now be described with the aid of figures, in which like elements are designated with the same reference numerals in the different figures.

[0053] The coupling interface is intended to be placed between a laser source and a treated subject 2. The subject 2 is for example an eyeball, more particularly a human or animal tissue to be treated, such as the cornea or the crystalline lens.

[0054] In the remainder of this specification, the invention will be described with reference to the treatment of the cornea of ​​a human or animal eye, although it will be apparent to those skilled in the art that the coupling interface according to the invention can be used in other applications.

[0055] 1. General description of coupling interfaces Referring to FIG. 2, the coupling interface includes: a ring 3 extending along a longitudinal axis A-A' and having a proximal end P and a distal end D; - a gel block 4 having a generally cylindrical shape.

[0056] The ring 3 comprises a double-walled partition 31 having an inner wall and an outer wall 311, 312, a perforated disk 32 (FIG. 3) at one end of the partition 31, a window 33 transparent to the laser beam at the other end of the partition 31, and a suction channel 34 opening between the walls 311, 312 of the partition 31. The double-walled partition 31 is arranged such that only the lower end 3121 of the outer wall 312 projects outside the ring 3. This lower end 3121 forms the proximal end P of the ring 3. In particular, the lower end 3121 of the outer side wall 312 constitutes a single ridge of the ring 3, which is intended to come into contact with the patient's eye 2 at its spherical periphery.

[0057] The window 33 is sealingly attached to the distal end D of the ring 3 to close the distal end D. The ring 3 is therefore only open at the proximal end P which is intended to be in contact with the patient's eye 2.

[0058] Partition 31, disk 32, and window 33 form two spaces in a ring: a circular suction chamber 35 in which a vacuum can be generated by connecting a suction unit to the suction channel 34, and - a working housing 36 configured to receive the gel block 4 and through which the laser light emitted by the laser source is applied to the tissue 2 to be treated; Determine.

[0059] To secure the coupling interface to the patient's eye 2 , the gel block 4 is mounted within the working housing 36 , the ring 3 and gel block 4 are placed over the patient's eye 2 , and a vacuum is created within the suction chamber 35 .

[0060] Prior to applying the vacuum, the patient's eye 2 - Gel block 4, and at the lower end 3121 of the outer side wall 312; It is brought into contact with the patient interface (forming a single ridge in contact with the patient's eye 2).

[0061] Thus, unlike existing coupling interfaces, attachment of the coupling interface to the eye 2 by the creation of a vacuum does not require a perfect bearing between two circular rims that define an annular groove.

[0062] With this novel design (i.e., the presence of a single circular rim 3121 and a deformable gel block 4), vacuum generation is simplified and more comfortable for the patient, since it is the coupling interface that conforms to the shape of the eye (through deformation of the gel block), and not the eye that conforms to the shape of the patient interface (as is the case with the device shown in FIG. 1).

[0063] Next, the coupling interface according to the present invention will be described.

[0064] 2. Detailed description of the coupling interface 2.1. ring With reference to Figures 2 and 3, a ring 3 with a double wall partition 31, a perforated disk 32, a transparent window 33 and a suction channel 34 is shown.

[0065] 2.1.1. Double wall partition The double walled partition 31 is generally cylindrical and open at both ends.

[0066] In particular, the double-walled partition 31 is composed of an inner side wall 311 and an outer side wall 312. Each side wall 311, 312 includes a respective upper end and a lower end. As mentioned above, the lower end 3121 of the outer wall 312 is intended to contact the patient's eye 2. The lower end 3121 of the outer side wall 312 may therefore advantageously be flared to best fit the shape of the eye 2. The flared lower end 3121 of the outer wall 312 may (for example) have an outwardly curved generally frustoconical shape that can be applied to the outer surface of the eye 2 in an atraumatic manner. With reference to FIG. 2, this flared lower end 3121 has a concave profile with a radius of curvature substantially equal to the radius of curvature of the eye 2 to allow tangential bearing.

[0067] 3, the lower end of the inner sidewall 311 is recessed toward the inside of the ring 3. Specifically, the lower end 3121 of the outer sidewall 312 protrudes outward, and the lower end of the inner sidewall 311 is offset toward the inside of the ring 3 along the longitudinal axis A-A'.

[0068] In particular, since the height h1 of the inner sidewall 311 is smaller than the height h2 of the outer sidewall 312, the lower end of the inner sidewall 311 is closer to the window 33 than the lower end 3121 of the outer sidewall 312.

[0069] The coupling interface therefore comprises a single circular ridge intended to come into contact with the patient's eye 2. The fact that the coupling interface comprises a single circular contact ridge (rather than two circular rims as proposed in conventional coupling interfaces as shown in FIG. 1 ) facilitates achieving full contact around the entire circumference of the contact line between the eye 2 and the ring 3.

[0070] 2.1.2. Perforated Disc The perforated disc 32 allows the connection of the inner and outer side walls 311, 312 of the double-walled partition 31. The perforated disc 32 comprises through lumens 321 or recesses intended to cooperate with the sclera of the patient's eye 2 when the coupling interface is placed on the patient's eye 2, and a vacuum is generated in the suction chamber 35, the conjunctiva is slightly sucked into these recesses, thus forming an integral assembly that reduces the risk of non-aspiration.

[0071] In the embodiment shown in Fig. 3, the perforated disk 32 has a substantially frustoconical shape such that the axis of the lumen of the disk 32 is directed towards the inside of the ring 3. Of course, the perforated disk 32 may have other shapes. For example, the perforated disk 32 may have the form of a truncated torus. In this case, the radius of curvature of the perforated disk 32 is selected in the range of 5 to 10 millimeters in order to optimize the fit of the disk 32 to the patient's eye 2.

[0072] The number and shape of the through lumens 321 may vary depending on the intended application. Preferably, the surface area of ​​the disc 32 that is covered by the lumens 321 is greater than the surface area of ​​the disc 32 that is not covered by the lumens 321. This allows for maximizing the ocular surface to which suction is applied, and therefore minimizing the level of vacuum (i.e., strength of vacuum) required to securely hold the coupling interface in position on the patient's eye 2.

[0073] 2.1.3. window Referring to FIG. 2, a window 33 transparent to the beam produced by the laser source is sealingly mounted at the top end of each of the inner and outer side walls 311 , 312 of the double-walled partition 31 .

[0074] The window 33 is disk-shaped. Of course, the window 33 may have other shapes (square, rectangular, oval) depending on the intended application.

[0075] Window 33 can be designed from a variety of materials such as glass or plastic (polycarbonate, poly(methyl methacrylate), etc.).

[0076] In the embodiment shown in Figures 2 and 3, the window 33 and the double-walled partition 31 are made of two separate parts. Nevertheless, in some embodiments, the window 33 and the double-walled partition 31 can be made in one piece (monoblock). This can limit the risk of leakage at the junction between the double-walled partition 31 and the window 33.

[0077] If the window 33 and the double-walled partition 31 are two separate parts of the ring 3, the window 33 may be attached to the double-walled partition 31 by gluing, welding, or other technique that allows the window 33 to be hermetically attached to the double-walled partition 31.

[0078] The window 33 may be anti-reflective or have any other type of optical treatment to enhance the transmission of the laser beam according to its wavelength.

[0079] 2.1.4. Suction Channel The ring 3 also comprises a tubular through-channel 34 formed in the outer side wall 312 of the double-walled partition 31. This channel, called the "suction channel", opens between the inner and outer walls 311, 312 of the double-walled partition 31 and extends radially outwardly, perpendicular to the axis A-A'.

[0080] The suction channel 34 allows to connect a remote device to the coupling interface via the nozzle, in particular to a suction device that creates a vacuum in a suction chamber 35 defined between the window 33, the inner and outer side walls 311, 312 and the perforated disk 32.

[0081] The presence of a single channel 34 limits the footprint of the coupling interface and reduces the number of nozzles and connectors.

[0082] 2.1.5. Other optional elements of the ring In addition to the above elements, the ring 3 may include a frusto-conical flange 39 connected by its smallest diameter rim to the upper end of the outer sidewall 312 .

[0083] Such flange 39 is open at its rim of greatest diameter and is integral with an annular collar 37 extending radially outwardly of the flange 39 .

[0084] Advantageously, this annular collar 37 comprises a layer 38 of flexible rubber on its surface opposite the flange 39, which allows the laser source to be easily fixed to the coupling interface by suction. Indeed, even if several solutions (mechanical, magnetic, etc.) are conceivable for fixing the laser source to the coupling interface, it is preferable to use a vacuum fixing means in order to limit the risk of "snaking" during this fixing process.

[0085] 2.2. Gel Block The coupling interface also comprises a gel block 4 intended to cooperate with the ring 3 .

[0086] 3, the gel block 4 is generally cylindrical in shape. The gel block 4 includes: - a side flank 41 having a shape complementary to the shape of the inner side wall, - a substantially flat circular upper base 42; - Concave circular lower base 43.

[0087] The gel block 4 is intended to be placed within the working housing 36 of the ring 3. Specifically, the side flank 41 of the gel block 4 is intended to contact the inner surface of the inner sidewall 311, the upper base 42 is intended to contact the window 33, and the lower base 43 is intended to contact the patient's eye 2.

[0088] To this end, the lower base 43 has a recess defined by a radius of curvature selected in the range of 5 to 10 mm, preferably in the range of 6.5 to 8.5 mm, thereby optimizing the fit of the lower base to the patient's eye 2.

[0089] Advantageously, the gel block 4 may be a hydrogel or other biocompatible, sterilizable, transparent, flexible material with optical properties compatible with the propagation of a femtosecond laser. For example, the hydrogel may comprise a mixture of fluorosilicone and hydrophilic monomers. Different hydrogel variants may be used, such as hydrogels with a water content of more than 70%, between 50% and 70%, or between 30% and 50%. This makes it possible to obtain gel blocks with different lubricating and optical properties, as well as different compressibility values.

[0090] In either case, the gel block 4 is sized and shaped so that it cooperates closely with the action housing 36 .

[0091] In particular, the height H of the gel block 4 is preferably substantially equal to or slightly greater than the height h1 of the inner side wall 311. This makes it possible to limit the risk of the gel block moving towards the suction chamber 35 during vacuum generation and the risk of the gel block being compressed between the tissue and the window during vacuum generation. Thus, the risk of the gel block being off-centered is reduced. This allows the coupling interface to be pressed against the eye 2 to be treated. between the gel block 4 and the window 33, and / or between the gel block 4 and the patient's eye 2 Avoid the presence of air bubbles.

[0092] It is also preferred that the diameter of the gel block 4 is substantially equal to or slightly smaller than the diameter (11 to 14 mm) of the inner side wall 311. This ensures mobility along the axis A-A' and facilitates insertion of the gel block into the working housing.

[0093] Finally, in order for the gel block 4 to hold the patient's eye 2 in place, the distance between the upper and lower bases of the gel block 4 is: - in the center of the circular lower base, it may be in the range of 1 to 2.5 mm; - at the lower base periphery it may be substantially equal to 4.5 and 6 millimeters.

[0094] 3. Operating Principle The operating principle of the coupling interface according to the invention will now be explained in more detail with reference to the coupling interface shown in FIGS. 2 and 3 and the method shown in FIG.

[0095] The suction channel 34 is assumed to be previously connected to a suction device (not shown) via a nozzle.

[0096] In a first step 100 , the practitioner inserts the gel block 4 (under sterile conditions) into the working housing 36 and presses the gel block 4 into the bottom of the housing until the distal flat portion of the gel block adheres to the window 33 .

[0097] In a second step 200, the practitioner places the ring 3 and gel block 4 over the eye 2 such that the center of the eye is aligned with the assembly of the ring and gel block 4. When the coupling interface (ring + gel block) is centered over the patient's eye, the practitioner brings the lower end 3121 of the outer sidewall 312 into contact with the periphery of the patient's eye 2, or more precisely, with the surface of the eyeball covered by the conjunctiva.

[0098] Once the coupling interface is properly centered on the patient's eye 2, the practitioner activates the suction device (step 300). Activation of the suction device allows the creation of a vacuum in the suction chamber 35, which applies suction. This vacuum causes the conjunctiva covering the sclera of the eye 2 to be sucked by the through lumen 321 of the perforated disc 32, thereby limiting the movement of the eye 2 relative to the coupling interface. The orientation of the through lumen 321 (whose axis of symmetry is oriented along the axis A-A') allows the application of a tangential force to the patient's eye 2 that tends to fixate the eye 2, facilitating fixation of the eye 2.

[0099] The eye 2 presses on the one hand against the lower end 3121 of the outer side wall 312 and on the other hand against the gel block 4. Due to its malleability the gel block adapts perfectly to the shape of the patient's eye 2.

[0100] Once the coupling interface is adhered to the eye 2, the practitioner controls the docking of the laser source onto the coupling interface (step 400) while keeping the suction device activated. Advantageously, the fixation of the laser source (which may be mounted, for example, on an articulated arm as described in WO2019 / 145487) to the coupling interface is performed by suction to limit unintended movement of the coupling interface.

[0101] 4. conclusion Surgical procedures performed in ophthalmology that use laser sources (especially femtosecond lasers) typically use a system for holding the eye, which must be active throughout the entire period of the patient's exposure to the laser beam.

[0102] In practice, in the event of unexpected and uncontrolled movements of the eye, there is a risk that the beam will reach areas where it is not intended to act, resulting in more or less severe lesions of intraocular structures.

[0103] The coupling interface described above allows for optimal holding of the eye and provides the practitioner with precise knowledge of the eye's position in space in order to precisely target the laser beam.

[0104] The reader will appreciate that many modifications may be made to the invention described above without materially departing from the novel teachings and advantages set forth herein.

Claims

1. A coupling interface (2) between a laser source and the tissue to be treated, said coupling interface comprising a ring (3) having a proximal end (P) for contacting the tissue to be treated (2) and an opposite distal end (D), and - Gel block (4) Equipped with The ring (3) A double-walled partition (31), said double-walled partition (31) comprising an inner sidewall (311) having an upper end and a lower end; and an outer sidewall (312) having upper and lower ends; a double-walled partition (31), wherein the lower end of the inner sidewall (311) is closer to the distal end (D) than the lower end (3121) of the outer sidewall (312), and the upper ends of the inner and outer sidewalls (311, 312) are closer to the distal end (D) than the lower ends of the inner and outer sidewalls (311, 312); a perforated disk (32) between the lower ends of the inner and outer side walls (311, 312) and including a through bore (321); a window (33) sealingly attached to the upper ends of the inner and outer side walls (311, 312) so as to close the distal end (D) of the ring (3) and transparent to the laser beam generated by the laser source, said window (33) comprising: a suction chamber (35) around the perforated disk (32), the inner sidewall (311) and the outer sidewall (312); a working housing (36) disposed at the center of the inner side wall (311); a window (33) defining a suction channel (34) extending between the inner and outer faces of the outer side wall (312) so as to open into a suction chamber (35), said suction channel (34) being intended to be connected to a suction module for generating a vacuum in the interior space defined by the suction chamber (35); and The gel block (4) is intended to be removably mounted within a working housing (36), slidable along the inner side wall of the double-walled partition, and has the following features: a side flank (41) having a shape complementary to the shape of the inner sidewall (311) and intended to contact the inner surface of the inner sidewall (311); a substantially flat circular upper base (42) intended to be in contact with the window (33); and a lower base (43) intended to come into contact with said tissue to be treated (2); It includes, A coupling interface comprising:

2. 2. The coupling interface according to claim 1, characterized in that the height (H) of the gel block (4) is substantially equal to the height (h1) of the inner side wall (311) of the double-walled partition (31).

3. 2. A coupling interface according to claim 1, wherein the double-walled partition (31) and the gel block (4) are cylindrical in shape and the diameter of the gel block (4) is substantially equal to the diameter of the inner side wall (311) of the double-walled partition (31), for example between 11 and 14 millimeters.

4. The lower base (43) of the gel block (4) is concave, and the distance between the upper base (42) and the lower base (43) is: - in the middle of the lower base (43) between 1 and 2.5 mm; - substantially equal to 4.5 and 6 millimeters around the circumference of the lower base (43); 2. A coupling interface according to claim 1, characterized in that

5. 2. The coupling interface of claim 1, wherein the lower base (43) of the gel block (4) is concave, and the radius of curvature of the lower base (43) is in the range of 6.5 to 8.5 millimeters.

6. 2. A coupling interface according to claim 1, wherein the height (h2) of the outer side wall (312) is greater than the height (h1) of the inner side wall (311) such that the lower end of the inner side wall (311) is closer to the window (33) than the lower end (3121) of the outer side wall (312), and the perforated disk (32) connecting the lower ends of the inner and outer side walls (311, 312) is substantially frusto-conical in shape such that the axis of the through bore (321) is oriented towards the longitudinal axis (A-A') of the ring (3).

7. 2. The coupling interface according to claim 1, characterized in that the surface area of ​​the perforated disk (32) covered by the through bore (321) is greater than the surface area of ​​the perforated disk (32) not covered by the through bore (321).

8. 2. A coupling interface according to claim 1, wherein the ring (3) further comprises a frusto-conical flange (39) opening at its maximum diameter rim and connected to an upper end of the outer side wall (312) by its minimum diameter rim.

9. 2. A coupling interface as claimed in claim 1, wherein the ring (3) further comprises an annular collar (37) integral with the rim of maximum diameter, the collar (37) extending radially outwardly and including a flexible rubber layer (38) on a surface thereof opposite the flange (39).

10. The coupling interface of claim 1, wherein the double-walled partition (31), the flange (39) and the annular collar (37) are integral.

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