A device for adjusting corneal transplants.

Abstract

The present invention relates to an apparatus for adjusting at least one corneal ring segment of the CAIRS type, comprising at least one base having a support surface for supporting the corneal ring. The support surface includes an annular groove, which is shaped to accommodate and shape the corneal ring segment. The apparatus optionally comprises a lid having at least one opening. The lid is positioned to engage with the base by covering at least the annular groove. In certain embodiments, the apparatus further comprises a blade holder for engaging on the base. The blade holder has a cap on which a blade is provided, and means for engaging the cap on the base, allowing the cap to rotate about the central axis of the annular groove. The blade extends opposite to a portion of the annular groove.

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of corneal transplantation, in particular to the field of transplantation adjustment used for the treatment of keratoconus, and more particularly to the field of transplantation adjustment by the technique known as CAIRS (Corneal Allogeneic Intrastromal Ring Segment).

BACKGROUND ART

[0002] Keratoconus is a progressive, non-inflammatory disease caused by external factors such as allergic reactions or responses to harsh environmental conditions (high-temperature arid climates, intense ultraviolet rays), or by genetic factors such as thin corneas. It is characterized by thinning and deformation of the cornea into a conical shape. Vision is blurred and distorted. Its prevalence varies by region, affecting up to 5% of the population in some parts of the world.

[0003] In the early stages of the disease, visual impairment can be corrected by wearing glasses or hard contact lenses, which compensate for corneal deformation to a certain extent. Alternatively, visual impairment can be corrected by polymerizing collagen fibers within the corneal stroma (intrastromal) to strengthen corneal tissue (a technique known as cross-linking). At more advanced stages, keratoconus is treated surgically.

[0004] One of the surgical techniques used involves inserting a ring-shaped or ring-segment-shaped implant into a tunnel created within the corneal stroma (interstitium) at the periphery of the cornea using manual techniques or a femtosecond laser. Once inserted into the cornea, the implant exerts tensile force on the collagen fibers. This causes the collagen fibers to separate from each other, reducing corneal deformation. As a result, the refractive properties of the cornea improve, and the patient's vision improves. The implant can be made from polymethyl methacrylate (PMMA)-based synthetic materials. However, the introduction of synthetic foreign bodies has side effects, potentially causing biological rejection and even expulsion. Recently, a new technique has emerged that uses ring-shaped or ring-segment-shaped allografts harvested from the corneal stroma of a donor cornea as an alternative to synthetic implants. This technique is abbreviated as CAIRS (Corneal Allogenic Intrastromal Ring Segment). These grafts are cut from the donor cornea during surgery. This is a delicate procedure requiring a high level of surgical expertise. The two main steps are as follows: - A process of cutting out a ring (ring-shaped tissue) from the periphery of the donor cornea using a femtosecond laser, scalpel, or cutting punch, and - A process of cutting out segments of the corneal ring of a desired length using a scalpel or femtosecond laser, depending on the patient's anatomical structure and medical condition.

[0005] The segments obtained in this way are inserted into pre-formed tunnels in the recipient's cornea. Generally, this procedure involves inserting two segments into two tunnels formed at opposite positions on the periphery of the recipient's cornea.

[0006] Although the number of steps is small, preparing the graft is time-consuming and requires meticulous care, which places a burden on the surgeon and increases the surgical time. Furthermore, the obtained segments are frequently unusable (too small in size, ruptured during various procedures, etc.), resulting in the need to repeat the surgery on a new donor cornea. However, the number of corneas available is far less than what is needed.

[0007] To facilitate graft handling, recent literature suggests that an open-air drying step may be added, but this also increases the preparation time for the graft. Furthermore, the development of ring-shaped or ring-segment cutting punches, such as those described in reference US-A-11426307, makes it possible to simplify and ensure the process of cutting the ring to a predetermined segment size. Despite these improvements, the preparation of corneal ring segments remains difficult, time-consuming, and cumbersome, and continues to require the use of multiple corneas if the procedure is performed incorrectly.

[0008] The present invention aims to overcome at least some of the aforementioned drawbacks, particularly by proposing an apparatus that facilitates the adjustment of at least one corneal ring segment of the CAIRS type. [Overview of the project]

[0009] For this purpose, an apparatus for adjusting at least one CAIRS-type corneal ring segment (S) according to the present invention is provided to include at least one base having a support surface for supporting a corneal ring. The support surface is provided with an annular groove, the annular groove having a central axis perpendicular to the support surface. The annular groove is shaped to accommodate and shape the corneal ring segment.

[0010] Accordingly, the base according to the present invention allows corneal rings or corneal ring segments to be dried not only by preserving their arc shape, but also by shaping the ring segments according to other dimensions (thickness and width). This makes the corneal ring segments easier to handle, easier to insert into the tunnel formed in the recipient's cornea, and more suitable for the patient's morphology and condition.

[0011] Preferably, the annular groove is U-shaped or V-shaped, having a flat or rounded bottom surface along a plane parallel to the axis perpendicular to the support surface. The support surface may be provided with at least one notch, which may open laterally into the annular groove, and which may be positioned to facilitate gripping of the corneal ring segment.

[0012] The base according to the present invention may further include a chamber extending below the support surface, and at least one conduit having a first end opening into the chamber and a second end on the opposite side opening into the annular groove through at least one orifice.

[0013] The at least one orifice may be located in the bottom wall or side wall of the annular groove. It is preferably 0.04 mm to 0.3 mm, and more preferably 0.15 mm.

[0014] The base according to the present invention may further include means for circulating air within the chamber, the at least one conduit, the at least one orifice, and the annular groove. Advantageously, the means for circulating air may include an end piece for connection to a pump.

[0015] Optionally, the apparatus according to the present invention comprises a lid having at least one opening, which is positioned to engage with the base by covering at least the annular groove, and which holds the corneal ring in place within the groove during the drying process.

[0016] In a particular embodiment of the present invention, the apparatus further comprises a blade holder for engaging on the base. The blade holder has a cap on which a blade is provided, and means for engaging the cap on the base, allowing the cap to be rotated about the central axis of the annular groove. In this case, the blade extends opposite to a portion of the annular groove (4). The cap or the base includes at least one marker and an angle scale centered on the central axis of the annular groove, allowing the blade holder to be positioned on the base at a predetermined angle about the central axis of the annular groove, so that the blade penetrates and cuts the corneal ring positioned in the annular groove to obtain at least one corneal segment.

[0017] Advantageously, the engagement means is arranged to allow the blade holder to be engaged on the base between a first position (in which the blade holder is partially engaged on the base, allowing the blade holder to rotate on the base to determine an angle by positioning the marker to face a desired angle scale) and a second position (in which the blade holder is fully engaged on the base, allowing the blade to cut through the corneal ring along a plane parallel to the central axis according to a predetermined angle). According to the present invention, one of the blade holder and the base includes at least one marker, and the other of the blade holder and the base includes at least an angle scale. Preferably, the base includes at least an angle scale and the blade holder includes at least one marker. In a particular embodiment of the present invention, the angle scale extends radially around the periphery of the studs around the annular groove. Optionally, the angle scale may be marked on a wheel mounted so as to be rotatable around the central axis of the base.

[0018] To facilitate and ensure cutting, the cap may have at least one window that allows the surgeon to view a portion of the support surface of the base when the blade holder is engaged with the base. Advantageously, the at least one window may be positioned so that the scale on the base is visible to the surgeon when the blade holder is engaged with the base. Optionally, the at least one window may be positioned so that the annular groove on the base is further visible to the surgeon when the blade holder is engaged with the base. Preferably, the at least one window may be positioned so that the alignment of the marker with respect to the scale on the base is visible to the surgeon.

[0019] In a particular embodiment, the blade holder may have at least two windows: a central window for viewing at least a portion of the annular groove of the base, and at least one lateral window positioned for viewing the scale. Thus, the apparatus according to the present invention allows a surgeon to quickly and safely prepare (adjust) at least one corneal ring segment having a desired size and shape, ready to be inserted into a pre-formed tunnel in the cornea of ​​a recipient patient. In practice, the surgeon positions the corneal ring within the annular groove of the base support surface, and then, as a first step, dries the corneal ring within the annular groove. The surgeon may optionally use a lid during this drying process. Drying the corneal ring within the apparatus according to the present invention not only allows for shaping (modeling) of the ring by the shape of the annular groove, but also allows for faster and more uniform drying thanks to better air circulation compared to drying in open air. After drying, and if necessary, the lid is removed. In the second step, the surgeon engages the blade holder with the base without manipulating the corneal ring at all, and rotates the blade holder relative to the base to align the marker with the desired angle scale (generally 0°). The first penetrating cut (penetrating incision) into the corneal ring is then performed by fully engaging the blade holder with the base according to the pre-selected angle scale. Subsequently, the surgeon repeats the operation of rotating the blade holder relative to the base to determine the second cutting angle and performing the second penetrating cut. This makes it possible to obtain segments of the desired length and residual segments from the corneal ring. The operation of determining the angle and cutting can be repeated as many times as necessary to obtain the desired number of segments. If the angle scale is marked (engraved) on a wheel mounted on the base so as to rotate around the central axis of the base, the determination of continuous cutting angles is particularly facilitated. In fact, the first through cut can be performed without aligning the marker to a specific scale, and the second through cut can be easily performed by aligning a certain angle scale (generally 0°) with the first through cut, and then positioning the marker on the blade holder to face the desired angle scale for the second through cut.This is particularly advantageous when the surgeon seeks to obtain multiple segments of a desired length. Thus, to cut a second segment of the desired length, the surgeon rotates the wheel to align the desired angle mark (generally 0°) with the previously made second through-cut, and then, without calculation, performs a third through-cut by aligning the marker on the blade holder with the desired angle mark value. This operation allows the surgeon to obtain two segments of the desired length, plus a remaining segment from the corneal ring. In this way, the surgeon can easily cut multiple segments of the desired length by repeating the aforementioned process. Alternatively, at the surgeon's discretion, the drying process may be performed after the corneal ring cutting process. After the corneal ring segments have been cut and dried, they are carefully removed from the annular groove and directly inserted into the tunnel formed in the recipient patient's cornea.

[0020] Other features and advantages of the present invention will become apparent from reading the following description relating to certain non-limiting embodiments of the invention.

[0021] Refer to the attached drawing. [Brief explanation of the drawing]

[0022] [Figure 1] Figure 1 is a schematic perspective view of a base according to the present invention. [Figure 2a] Figure 2a is a schematic cross-sectional view along a plane passing through axis X in Figure 1, and is a perspective view detailing a stud that includes a support surface with an annular U-shaped groove having a rounded bottom. [Figure 2b] Figure 2b is a schematic cross-sectional view along a plane passing through axis X in Figure 1, and is a detailed perspective view of a stud including a support surface with an annular U-shaped groove having a flat bottom. [Figure 2c] Figure 2c is a schematic cross-sectional view along a plane passing through axis X in Figure 1, and is a detailed perspective view of a stud detailing a support surface having an annular V-groove with a flat bottom. [Figure 3]FIG. 3 is a schematic cross-sectional view along the plane passing through the axis X in FIG. 1, and is a perspective view of the device according to the present invention provided with the base with the lid engaged therewith. [Figure 4a] FIG. 4a is a schematic perspective view of the blade holder engaged with the base, which also shows a cross-section along the plane passing through the axis X in FIG. 1, wherein the marker of the blade holder is aligned with the 0 angle graduation on the base, and the base is entirely shown in a perspective view. [Figure 4b] FIG. 4b is a schematic perspective view of the blade holder engaged with the base, which also shows a cross-section along the plane passing through the axis X in FIG. 1, wherein the marker of the blade holder is aligned with the 45 angle graduation on the base, and the base is entirely shown in a perspective view. [Figure 5] FIG. 5 is a schematic plan view of the device according to the present invention provided with the base with the blade holder engaged therewith. [Figure 6] FIG. 6 is an exploded schematic cross-sectional view of the device according to the present invention along the plane passing through the axis X in FIG. 1, which is provided with the blade holder ready to be engaged with the base. [Figure 7] FIG. 7 is a schematic plan view of the device according to a specific embodiment of the present invention, which is provided with the base with the blade holder engaged therewith, wherein the base has a graduated wheel, and the blade holder has one central opening and at least one lateral opening. [Figure 8] FIG. 8 is a schematic perspective view of the blade holder engaged on the base according to a specific embodiment of the present invention, which also shows a cross-section along the plane passing through the axis X in FIG. 1, wherein the base has a graduated wheel, and the blade holder has one central opening and at least one lateral opening. [Figure 9] FIG. 9 is a schematic perspective view of a corneal ring segment prepared using the device according to the present invention. MODE FOR CARRYING OUT THE INVENTION

[0023] Referring to Figures 1 to 9, the present invention relates to an apparatus for preparing at least one segment S1, S2 of a CAIRS-C type corneal ring. The apparatus according to the present invention comprises at least one base 1, which is shown in particular in Figures 1, 2a, 2b, 2c and 3. According to one embodiment of the present invention, the base 1 of the apparatus is configured to rest on a work surface and includes a central annular element 1.2 having two surfaces of rotation about a central axis X, namely an outer surface 1.2a and an inner surface 1.2b that are equidistant from each other. These outer surface 1.2a and inner surface 1.2b are connected to each other by a flat upper surface 1.2c that is perpendicular to the central axis X and parallel to the work surface. The inner surface 1.2b defines a cylindrical housing capable of receiving a cylindrical stud 1.3 having a circular cross-section. In this case, the central annular element 1.2 is surrounded by a circular rim 1.1 positioned around the central annular element 1.2 so as to be opposite to the outer surface 1.2a, forming an annular trough 1.4 between them. In particular, the stud 1.3 shown in Figures 2a, 2b, and 2c has a tubular shape with one end closed by a partition. The partition has an upper surface that forms the support surface 2 of the corneal ring C. The stud 1.3 partitions a cavity 3 located below the support surface 2. When the stud 1.3 is inserted into the central annular element 1.2, the center of the support surface 2 is located on the central axis X. The stud 1.3 is inserted into the central annular element 1.2 such that the support surface 2 of the stud 1.3 is flush with the flat upper surface 1.2c of the central annular element 1.2, forming a substantially continuous circular surface. Here, the term "below" refers to the edge, surface, part, etc. located immediately adjacent to the work surface, and the term "above" refers to the edge, surface, part, etc. located on the opposite side. The support surface 2 of the stud 1.3 has an annular groove 4 having a central axis perpendicular to the support surface 2 and coinciding with the central axis X. The annular groove 4 is formed to accommodate and shape the corneal ring C. Therefore, the width of the groove 4 is defined according to the dimensions of the corneal ring C intended to be placed within the groove 4, and the groove 4 is slightly wider than the corneal ring C in order to provide clearance (gap) between the corneal ring C and the inside of the groove 4. In this illustrated example, the width of the groove 4 is at least 0.55 mm, and preferably 1.1 mm or more.In this case, the diameter of the groove 4 is 5 mm on the smaller diameter side and 6.6 mm on the larger diameter side. Furthermore, the bottom surface of the groove 4 is shaped to model the corneal ring C during the drying process. Preferably, it is a U-shape with a flat bottom surface as shown in Figure 2b, or a U-shape with a rounded bottom surface as shown in Figure 2a, or a V-shape as shown in Figure 2c. Those skilled in the art can determine the diameter, width, and depth of the groove 4 according to the dimensions (diameter, width, thickness) of the corneal ring to be received. Generally, the width of the groove 4 is between 0.55 mm and 1.1 mm, and its depth is between 0.4 mm and 1 mm. The support surface 2 is provided with at least one notch 5 that opens laterally into the annular groove 4. The notch 5 is positioned to facilitate gripping the corneal ring C or corneal ring segments S1, S2. Those skilled in the art know how to determine the shape, dimensions, and number of notches 5 necessary to facilitate the passage of surgical instruments. In particular, the depth of each notch 5 is slightly greater than the depth of the groove 4, and its length is slightly longer than the width of the groove 4. This allows the corneal ring or corneal ring segment to be grasped, for example, by using a clamp or hook and sliding one branch of the clamp through one of the notches 5 against the bottom surface of the groove 4 below the corneal ring or corneal ring segment (with the other branch of the clamp gripping the opposite side), or by inserting the hook below the corneal ring or corneal ring segment. In this case, each notch 5 is more or less rectangular or oval, with a width of about 0.6 mm and a length and depth at least equal to the width and depth of the groove 4. The base 1 further has a chamber 3 extending below the support surface 2. In this case, the support surface 2 is formed by studs 1.3. The studs 1.3 are hollow. The base also has several conduits 4.2, the first ends of which open into the chamber 3, and the second ends of which open into the annular groove 4 via orifices 4.1. The orifices 4.1 are arranged at equal intervals on the bottom wall and / or side wall of the annular groove 4. Those skilled in the art will know how to adjust the number (one may suffice), shape, and dimensions of the orifices depending on the dimensions of the annular groove 4.In this case, the orifice is circular in cross-section, has a diameter between 0.04 mm and 0.3 mm, and is evenly distributed across the bottom and side walls of the annular groove 4. The base 1 of the apparatus according to the present invention may also have a chamber 3, a conduit 4.2, an orifice 4.1, and means for circulating air within the annular groove 4. According to a particular embodiment of the present invention, the means for circulating air includes an end piece 6 for connection to a pump (not shown). Here, “pump” means any device, manual, pneumatic, or electric, that enables the blowing in or sucking in air. As an example, the connecting end piece 6 may be connected to a bulb (poire) or a conventionally used electric pump, such as the “ACP system” type pump sold by Moria, for example. In this case, air is blown in by the pump, distributed through the connecting end piece 6 into the chamber 3, flows through the conduit 4.2 from the orifice 4.1 into the annular groove 4, and dries the corneal ring or corneal ring segment placed within the annular groove 4. Those skilled in the art can determine the flow rate, pressure, and duration of the supplied air to improve drying without the corneal ring or corneal ring segment moving out of the annular groove 4 or deteriorating. As an example, a pump providing airflow of 200 mmHg may be used. The base 1 can be manufactured from any material, preferably a sterilizable material. The support surface 2 and the annular groove 4 are manufactured from a non-stick material, such as polytetrafluoroethylene (i.e., Teflon®). This may be the material constituting the studs 1.3 or the material for the upper covering of the studs. Drying the corneal ring or corneal ring segment by placing it in the annular groove of the apparatus not only allows for a reduction in drying time but also allows for obtaining corneal segments S1, S2 that are shaped (modeled) as arc-shaped as shown in Figure 9, respectively. The cross-section in the thickness direction of the segments S1, S2 is U-shaped with a flat bottom, U-shaped with a rounded bottom, or V-shaped. These shapes facilitate insertion of the corneal segment into a tunnel formed in the cornea of ​​the recipient patient.

[0024] Optionally, as shown in Figure 3, for example, the apparatus according to the present invention may include a lid 7 positioned to engage with the base 1 so as to cover at least a corneal ring or corneal ring segment placed within the annular groove 4. This allows the corneal ring or corneal ring segment to be held in place within the groove 4. In this case, the lid 7 is rotationally symmetrical and has a circular upper wall 7.1 having a central axis X2, and a tubular wall 7.2 extending downward from the periphery of the upper wall 7.1. When the lid 7 is engaged on the base 1, the central axis X2 of the lid 7 coincides with the central axis X of the base 1, the upper wall 7.1 of the lid 7 faces the support surface 2 of the base 1, and the tubular wall 7.2 of the lid 7 faces the outer surface 1.2a of the central annular element 1.2 of the base 1. Preferably, the upper wall 7.1 of the lid 7 is provided with openings 8 that allow control of the drying and shaping development (progress) of the corneal ring or corneal ring segment. These openings also allow for air circulation. A person skilled in the art can determine the shape, position, and dimensions of the opening. In this case, for example, there may be 10 openings (although one may suffice), which are rectangular or oval in shape and positioned on the radius of a circle whose center lies on the central axis X.

[0025] In certain embodiments of the present invention, as particularly shown in Figures 4 to 8, the apparatus further comprises a blade holder 10. The blade holder 10 includes a cylindrical cap 11 having a central axis X3, the cylindrical cap 11 having a closed-face forming upper end 11.1 partially opened by at least one window 12, and an annular lower end 11.2, both ends of which are connected by (lateral) edges 11.3. The joint between at least one window 12 and the edge 11.3 forms a shoulder 14. The cylindrical cap 11 further includes a blade 13 extending along a direction substantially parallel to the central axis X3 and fixed so as to face a portion of the annular groove 4 of the base 1, and having the function of penetrating and cutting the corneal ring C. In this case, the blade holder includes a cap on which the blade is provided, and means for engaging the cap onto the base, allowing the cap to rotate about the central axis of the annular groove. In this case, the blade extends facing a portion of the annular groove 4. The cap or base includes at least one marker and an angle scale centered on the central axis of the annular groove, and the blade holder is positioned on the base at a predetermined angle about the central axis of the annular groove, so that the blade penetrates and cuts the corneal ring, which is positioned in the annular groove, to obtain at least one corneal segment. In this case, the blade 13 is secured by a tubular support 13.1 that protrudes from the center of the closing surface forming upper end 11.1 of the cap 11. Those skilled in the art will know how to determine the width, height, and tip shape of the blade 13 so that the cutting edge of the blade 13 enters the annular groove 4 and reaches its bottom. As an example, the cutting edge of the blade 13 has a shape complementary to the shape of the annular groove 4. In other words, if the bottom of the annular groove 4 is flat or rounded U-shaped, the cutting edge of the blade 13 can be straight or rounded, and if the bottom of the annular groove 4 is V-shaped, the cutting edge of the blade 13 can be V-shaped.Furthermore, the cap 11 includes reciprocating engagement means for the cap 11 with respect to the base 1, which are formed by the edge 11.3 of the blade holder 10 and the outer surface 1.2a of the central annular element 1.2 of the base 1, respectively, allowing the cap 11 to rotate around a corresponding central axis X, X3. The reciprocating engagement means 11.3, 1.2a are arranged to allow the blade holder 10 to engage with the base 1 between a first position (in which the blade holder 10 is partially engaged with the base 1, allowing the blade holder 10 to rotate on the base 1 to adjust the cutting angle) and a second position (in which the blade holder 10 is fully engaged with the base 1, allowing the blade 13 to cut through a corneal ring or corneal segment positioned in the annular groove 4 of the base 1 according to a predetermined angle). Those skilled in the art may provide positioning means for the blade holder 10 with respect to the base 1 on the base 1 and / or on the blade holder 10. As a non-limiting example, the trough 1.4 may be provided with at least one spring. When the blade holder 10 is partially engaged on the base 1, the spring is not compressed and the blade 13 is not in contact with the support surface 2. To cut the corneal ring C, the surgeon applies pressure to the cap 11 of the blade holder 10, compressing the spring and fully engaging the blade holder 10 on the base 1. This allows the cutting to be performed. Those skilled in the art may design or arrange the positioning means such that, in a first position, the blade 13 of the blade holder 10 does not come into contact with the support surface 2 when the surgeon determines the cutting angle, and in a second position, the blade 13 penetrates and cuts through the corneal ring. Either the cap 11 or the base 1 has at least one marker 15a, 15b, and the other cap 11 or base 1 has an angle scale 16 centered on the central axis X of the annular groove 4. This allows the blade holder 10 to be positioned by rotation on the base 1, and the cutting angle to be adjusted around the central axis X of the annular groove 4.In a particular embodiment of the present invention, the cap 11 has a first marker 15a marked on the closing surface 11.1 so as to face the window 12, and a second marker 15b provided on the shoulder portion 14 to complement the first marker. These markers 15a and 15b are aligned with each other to indicate the position of the blade 13. The angle scale 16 is centered on the central axis X. The angle scale 16 extends radially around the periphery of the studs 1.3 around the annular groove 4. In this case, the angle scale 16 is located on the upper surface 1.2c of the central annular element 1.2 of the base 1 and is positioned along the radius of the circle forming the outer contour of the upper surface 1.2c, which is centered on the central axis X. Optionally, as shown in Figures 7 and 8, for example, the angle scale 16 may be marked on a wheel 1.5 that is rotatably mounted on the central annular member 1.2 around the central axis. In this case, the wheel 1.5 has a flat upper surface 1.5c marked with an angle scale 16, and an opposite lower surface 1.5d connected by two sides 1.5a and 1.5b. A person skilled in the art can assemble the wheel 1.5 and the central annular element 1.2 such that the wheel is not only rotatable about a central axis X, but the flat upper surface 1.5c of the wheel forms a continuous surface, preferably a substantially flat surface, with the upper surface 1.2c of the central annular element 1.2 and the support surface 2 of the stud 1.3. As an example, the central annular element 1.2 may have an L-shaped annular guide portion 1.6 formed as a recess in the upper surface 1.2c of the central annular element 1.2, and the guide portion 1.6 can rotatably accommodate the wheel 1.5. In this case, rotation is possible simply by sliding the surfaces 1.5a and 1.5d inside the guide portion 1.6 and sliding the surface 1.5b relative to the stud 1.3. Those skilled in the art know how the shape of the guide portion 1.6 and the shapes of its complementary surfaces 1.5d, 1.5a, and 1.5b should be defined to enable the wheel to rotate and to obtain stability in the position of the wheel 1.5 at a position selected by the surgeon. In this case, the guide portion 1.6 has an inner rim 1.6a that forms a rail into which a complementary rim 1.5e, cut into the surface 1.5a of the wheel 1.5, is fitted.Those skilled in the art can provide means for fixing the position.

[0026] Those skilled in the art know how the markers 15a, 15b and the angle scale 16 should be manufactured so that they are fully legible. Thus, they can be marked, printed, engraved, and / or embossed. The intervals of the angle scale 16 can, for example, be set at 5° intervals and may be accompanied by numerical markings at 15° intervals from 0° to 345°. For a corneal ring with a diameter D of 7.75 mm, an angle α of 5° corresponds to a corneal segment length l = 0.34 mm (l = πD × α / 360). The length of the lines of the angle scale 16 may differ depending on whether the angle scale 16 is accompanied by angle numerical markings. In this case, the angle scale 16 accompanied by angle numerical markings is represented by lines that are substantially longer than the lines representing the angle interval scale 16. Preferably, if the angle scale 16 is marked on the upper surface 1.2c of the central annular element 1.2, a person skilled in the art will ensure that when the blade holder 10 is engaged on the base 1, the blade 13 does not face any of the orifices 4.1 opening into the annular groove 4 at any of the positions indicated by the angle scale 16. Furthermore, as described above, the cap 11 has at least one window 12, preferably formed to face the markers 15a, 15b, so that when the blade holder 10 is engaged on the base 1, a portion of the flat surface 1.2c of the base 1 marked with the angle scale 16 is visible. Optionally, the window 12 is positioned so that the annular groove 4 of the base 1 is also visible when the blade holder is engaged on the base. Preferably, as shown in Figure 7, the cap 11 has at least two windows (in this case four), for example, one lateral window 12.1 (in this case three) that allows the surgeon to view the angle scale 16, and a central window 12.2 that allows the surgeon to view (and optionally hold or manipulate) the corneal ring or corneal ring segment positioned within the annular groove 4.To facilitate and make more precise positioning of the blade holder relative to the base, a first marker 15a, marked on the closing surface 11.1, faces the central window 12.2, and a second marker 15b, complementing the first marker, is located on the shoulder portion 14 facing the side window 12.1. These markers 15a and 15b are aligned with each other to indicate the position of the blade 13.

[0027] Therefore, in order to cut the corneal ring C pre-positioned in the annular groove 4 of the support surface 2 of the base 1, the surgeon engages the blade holder 10 by aligning the markers 15a, 15b of the blade holder 10 with the angle scale 16 of the base 1, which is normally marked "0" and visible through at least one window 12.1, 12.2. The surgeon then fully engages the blade holder 10 until the blade 13 contacts the bottom surface of the annular groove 4. At this position, the blade 13 makes the first through cut of the corneal ring C. As a second step, the surgeon slightly lifts the blade holder 10 and returns it to the partially engaged position to fully disengage the blade 13 from the corneal ring C, and then rotates it until the markers 15a, 15b face the selected angle scale 16. The blade holder 10 is then fully engaged again on the base 1, and the second through cut is made when the blade 13 again contacts the bottom surface of the annular groove 4. This makes it easy to obtain a corneal segment S1 of the desired length and a segment Sr corresponding to the remainder of the corneal ring C. All these operations can be repeated by selecting the angle scale 16 to correspond to the desired length of the corneal segment S2, positioning the markers 15a and 15b opposite the angle scale 16, then fully engaging the blade holder 10 again onto the base 1, so that the blade 13 contacts the bottom surface of the annular groove 4 again. This makes it easy to obtain a corneal segment S2 of the desired length. This makes it possible for the surgeon to obtain two segments S1 and S2 of the desired length (S1 and S2 may or may not be the same length) and a third segment Sr corresponding to the remainder of the corneal ring C. In other words, the lengths of the three segments S1, S2, and Sr define the circumference of the corneal ring C. If the angle scale 16 is marked on the wheel 1.5, these operations for producing the corneal segments are even easier.In fact, the surgeon can align the selected angle scale (typically the "0" scale) with the markers 15a and 15b on the blade holder by rotating the wheel 1.5, which corresponds to the second cut. Then, the blade holder is rotated until the markers 15a and 15b face the desired angle scale, and a third cut is made. This procedure can be repeated as many times as needed without any calculations. As a result, the surgeon can easily cut a number of segments S1, S2, ... of the desired length from the corneal ring C by repeating the aforementioned process, and obtain the remaining segment Sr.

[0028] Accordingly, the apparatus according to the present invention, as shown in Figure 9 for example, allows a surgeon to obtain at least one corneal segment S1, S2 of a desired length from the corneal ring C while limiting the manipulation of the corneal ring C and the corneal ring segment. In fact, once the corneal ring C is placed in the annular groove 4, the subsequent cutting is performed without any manipulation of the corneal ring or corneal ring segment. After the drying and cutting steps are performed, the segment only needs to be collected, and the segment is ready to be directly implanted into the cornea of ​​the recipient patient.

[0029] Accordingly, the apparatus according to the present invention allows for the rapid drying, shaping (modeling), and cutting of at least one corneal segment S1, S2 of a desired length from the corneal ring C, while limiting the scope of operation. Furthermore, the resulting corneal segments S1, S2 are perfectly fitted to the recipient patient's eye in terms of shape and length, and are easily inserted into the tunnel formed in the recipient patient's eye. The apparatus according to the present invention also allows the surgeon to perform the drying and cutting steps independently of each other in any desired order.

[0030] Naturally, the present invention is not limited to the embodiments described, but encompasses any modifications that fall within the field of the invention as defined in the claims.

[0031] In particular, the studs 1.3 may be detachable and replaceable to fit the diameter of the corneal ring C without requiring any other elements of the base 1 to be modified, or they may be integrally molded with the base. Accordingly, those skilled in the art may provide the cover 7 as a general-purpose cover that covers the annular groove 4 regardless of its diameter. Naturally, the blade holder 10 must be selected to be compatible with the annular groove 4 of the support surface 2, so that the corneal ring C can be cut by the blade 13.

[0032] The orifices 4.1 of the annular groove 4 may be provided only on the bottom wall of the annular groove 4, only on the side wall of the annular groove 4, or on both the bottom wall and the side wall of the annular groove 4. All orifices 4.1 may have the same diameter, or they may have different diameters depending on their location. Those skilled in the art know how to determine the number, shape, location, size, and density of the orifices depending on the diffusion of air to be achieved within the annular groove 4. In particular, the orifices may be substantially circular, oval, rectangular, square, slotted, or mesh-like.

[0033] According to embodiments of the present invention, air may be blown in, or it may be aspirated.

[0034] Base 1 includes an air circulation means having an end piece for connection to a pump. However, it is also possible that Base 1 is not connected to a pump, and the air circulation between Chamber 3, Conduit 4.2, and Orifice 4.1 is passive. In this case, air can enter Chamber 3 through a passage provided in the circular rim 1.1.

[0035] Base 1 includes an air circulation means, but alternatively, the air circulation means may be provided on the lid 7. In this case, an end piece for connecting to a pump is located in the center of the lid 7. Air blown or drawn in by the pump is supplied through the end piece and through the lid 7 to the support surface 2. The air then passes through the orifice 4.1 of the annular groove 4 and through the conduit 4.2 to reach the chamber 3, from where it is discharged through an opening provided for that purpose. When the lid 7 is used for air diffusion, those skilled in the art will know how the lid 7 should be adapted.

[0036] The upper surface 1.5c of the wheel 1.5 forms a continuous surface, preferably a substantially flat continuous surface, with the upper surface 1.2c of the central annular element 1.2 and the support surface 2 of the stud 1.3. However, the upper surface 1.5c of the wheel 1.5 may be concave or convex with respect to the upper surface 1.2c of the central annular element 1.2 and the support surface 2 of the stud 1.3.

[0037] According to embodiments of the present invention, the corneal ring C is first dried on the base 1 and then cut by engaging the blade holder 10 with the base 1. However, the surgeon may also choose to perform these steps in the reverse order. That is, the corneal segment C may be cut first using the blade holder 10, followed by the drying and shaping steps. Alternatively, the surgeon may distinguish between the steps and use the apparatus according to the present invention to perform only the drying and shaping of the corneal ring segment or the corneal ring, or only the cutting thereof.

[0038] In this case, the marker 15 is provided on the blade holder 10 and the angle scale 16 is provided on the base 1, but the reverse is also possible. That is, the marker 15 may be marked on the base and the angle scale 16 may be marked on the blade holder 10. Those skilled in the art will know how the markers and angle scales should be adapted. In this case, the blade holder 10 has two markers 15a, 15b, but it may have only one of them. A marker may also be marked on the base 1 if it is deemed useful by those skilled in the art. For example, it may be marked to align with the angle scale "0" and / or the most frequently used angle scale.

[0039] The means for reciprocally engaging the blade holder 10 on the base 1 includes a positioning means. This allows the surgeon to "feel" where the blade holder 10 is positioned between a partially engaged position and a fully engaged position. In this case, the positioning means includes a spring. However, it may also be a piston, a notch or stopper mechanism, and / or a color marking.

[0040] Alternatively, the blade 13 may be retractable (and extendable) so that it is in a retracted position while the blade holder 10 is rotating to determine the angle, and then in an extended position for penetrating and cutting the corneal ring C or corneal ring segment S after the angle has been determined. As an example, the blade may be equipped with a push button or lever which allows the blade to be extended (to the extended position) and / or retracted (to the retracted position) after the blade holder 10 has engaged with the base 1.

Claims

1. A device for adjusting a CAIRS-type corneal ring segment (S), The device comprises at least one base (1) provided with a support surface (2) for supporting a corneal ring (C), The support surface (2) includes an annular groove (4), The annular groove (4) has a central axis (X) perpendicular to the support surface (2), The annular groove (4) is shaped to accommodate and form the corneal ring or the corneal ring segment. A device characterized by the following features.

2. The annular groove (4) has a U-shape or V-shape, with a flat or rounded bottom surface, along a plane parallel to the axis perpendicular to the support surface (2). The apparatus according to feature 1.

3. The support surface (2) is provided with at least one notch (5), The at least one notch (5) opens laterally into the annular groove (4), The at least one notch (5) is positioned to facilitate gripping of the corneal ring or the corneal ring segment. The apparatus according to feature 1.

4. The aforementioned base (1) is A chamber (3) extending below the support surface (2), At least one conduit having a first end opening into the chamber (3) and a second end on the opposite side opening into the groove via at least one orifice (4.1), The apparatus according to claim 1, characterized by including the following:

5. The at least one orifice (4.1) is located in the bottom wall or side wall of the annular groove (4). The apparatus according to feature 4.

6. The at least one orifice (4.1) is 0.04 mm to 0.3 mm, preferably 0.15 mm. The apparatus according to feature 4 or 5.

7. The base includes means for circulating air within the chamber (3), the conduit, the at least one orifice (4.1), and the annular groove (4). The apparatus according to any one of 4 to 6.

8. The means for circulating the air includes an end piece (6) for connecting to a pump. The apparatus according to feature 7.

9. A lid (7) is provided with an opening (8) and is positioned to engage with the base (1) by covering at least the annular groove (4), and holds the corneal ring or the corneal ring segment in a predetermined position within the annular groove (4). The apparatus according to any one of claims 3 to 7, further comprising the above.

10. Blade holder (10) Furthermore, The blade holder (10) is A cap (11) on which a blade (13) is provided, Means (11.3, 1.2a) for reciprocating engagement of the cap (11) onto the base (1), It has a cap (11) that allows the cap (11) to rotate around the central axis (X) of the annular groove (4), The blade (13) extends opposite to a part of the annular groove (4), One of the blade holder (10) and the base (1) includes at least one marker (15a, 15b), and the other of the blade holder (10) and the base (1) includes an angle scale (16) centered on the central axis (X) of the annular groove (4), and the blade holder (10) can be positioned on the base according to a predetermined angle around the central axis (X) of the annular groove (4). The blade (13) penetrates and cuts through the corneal ring (C) to obtain at least one corneal segment. The apparatus according to any one of claims 1 to 9.

11. The angle scales (16a, 16b) extend radially on the base (1) around the studs (1.3) surrounding the annular groove (4). The apparatus according to claim 9 or 10, which is dependent on any one of claims 4 to 8.

12. The angle scales (16a, 16b) are marked on a wheel (1.5) mounted on the base (1) so as to rotate around the central axis (X). The apparatus according to feature 11.

13. The cap (11) has at least one window (12) that allows a portion of the support surface to be visible when the blade holder (10) is engaged with the base (1). The apparatus according to any one of claims 10 to 12.

14. The cap (11) has at least two windows (12.1, 12.2), one of which allows the angle scale (16) to be viewed, and the other which allows at least a portion of the annular groove (4) to be viewed. The apparatus according to feature 13.

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