ORBITAL IMPLANT WITH THROUGH-THROUGH WINDOWS FOR SUTURATIONS

Abstract

The invention relates to an assembly comprising an orbital implant of substantially spherical shape intended to replace an eyeball after enucleation and / or evisceration and at least one suture thread, the implant consisting of a basic body (1) made of porous material, in particular which promotes colonization by the body, and a posterior or rear element (2) with through windows covering a part of the basic body, and the posterior element comprising a plurality of through windows through which the at least one suture thread passes for suturing the oculomotor muscles in and out of the space defined between the base body and the posterior element; the posterior element (2) with windows is fixed to the basic body and has at least a window, preferably a plurality of windows, in particular four windows (7); the windows have respective edges, in particular respective lower edges and are at least partially defined and delimited by the basic body.

Description

Title of the invention: Orbital implant comprising through windows for sutures

[0001] The present invention relates to a substantially ball-shaped orbital implant intended to replace an eyeball after enucleation and / or evisceration.

[0002] Already known from the prior art, and in particular from US 8,118,867, is an orbital implant comprising a ball made of a porous material intended to fill the orbital cavity and coupled, on the posterior or rear side, to an element substantially in the form of a half-shell, which partially covers the posterior part of the ball. The half-shell comprises through windows for the passage of suture threads for the oculomotor muscles. This half-shell is made of a non-porous degradable material, while the ball is made of a non-degradable porous material, for example porous hydroxyapatite.

[0003] These prior art orbital implants have several drawbacks. They are difficult to implant. In addition, they have a high rate of failure or rejection of the implantation, which often requires repeating the operation several times.

[0004] The present invention aims to overcome the drawbacks of the prior art by proposing a substantially ball-shaped orbital implant, which is easier to implant and which in particular has a lower, or even zero, failure or rejection rate.

[0005] According to a first aspect of the invention, an orbital implant of substantially spherical shape intended to replace an eyeball after enucleation and / or evisceration is constituted by a base body made of a porous material, in particular which promotes colonization by the organism, and a posterior or rear element with through windows covering a part of the base body, the posterior element comprising a plurality of through windows for the passage of suture threads for suturing the oculomotor muscles in and out of the space defined between the base body and the posterior element, is characterized in that the posterior element with windows is fixed to the base body, at least one window, preferably a plurality of windows, in particular four windows, having a respective edge, in particular a respective lower edge, at least partly defined and delimited by the base body.

[0006] By thus providing on the one hand to fix the window element to the basic body, in particular in the form of a ball, made of colonizable porous material in such a way that at least part of the edge, in particular the lower edge of the window(s), is formed by the basic body, it is ensured that the sutured muscle(s) are in good contact with the edge of the window and the part of the surface of the basic body under the window and will thus colonize properly, unlike the prior art where it was in contact with the non-colonizable material of the shell. Thus, the suture is better performed, the ball is more stable in the final position and the rejection rate of the insertion operation is lower.

[0007] According to a second aspect of the invention, which constitutes in itself an invention which can be carried out independently of the first object above, but also in combination therewith, an orbital implant of substantially spherical shape intended to replace an eyeball after enucleation and / or evisceration is constituted by a basic body made of a porous material, in particular which promotes colonization by the organism, and a posterior or rear element with through windows covering a part of the basic body, the posterior element comprising a plurality of through windows for the passage of suture threads for suturing the oculomotor muscles in and out of the space defined between the basic body and the posterior element, and by defining for the implant of substantially spherical shape a reference mark passing through its center, a vertical axis Z corresponding to the anterior-posterior axis and two axes XY in the equatorial plane,reference point with respect to which the angles of latitude and longitude of any point on the surface of the implant are defined, the angle of longitude of the most posterior or rear pole, called the upper pole, being 90° while the angle of longitude of a point at the equator is 0°, is characterized in that the window element comprises at least one first lower through window, which extends over a first lower range of longitudes, and at least one second upper opening, which extends over a second upper range of longitudes, and there is at least one meridian extending from the equator to the pole which crosses or passes through both the lower and upper windows.

[0008] Preferably, the lower range of longitudes and the upper range of longitudes are distinct from each other, i.e. do not overlap, for example the first range being equal to [60°,70°] and the second range being equal to [75°,85°].

[0009] By thus providing at least two lower and upper windows to allow the passage of suture threads alternately, for example in a first direction through the lower window into the space defined between the base body and the window element, then through the upper window out of said space in another direction or vice versa but which may be in the same direction as the first direction, the ergonomics of introducing the suture threads are greatly improved for the surgeon, which he can thus carry out in a direction which in particular corresponds to a meridian.

[0010] According to yet another aspect of the invention constituting in itself an invention which can be implemented independently of each of the two other aspects above, but also in combination with one and / or the other of the two preceding aspects, an orbital implant of substantially spherical shape intended to replace an eyeball after enucleation and / or evisceration is constituted by a basic body made of a material porous, in particular which promotes colonization by the organism, and a posterior or rear element with through windows covering a part of the base body, the posterior element comprising a plurality of through windows for the passage of suture threads for suturing the oculomotor muscles in and out of the space defined between the base body and the posterior element, is characterized in that at least one through window, in particular the at least one upper window, has a triangular shape, one point of which is oriented towards the upper pole of the implant.

[0011] Providing such a geometry of at least one window, in particular several windows, in particular upper windows, gives the surgeon great ease in inserting and extracting the suture threads into and out of the space between the window element and the base body.

[0012] According to a preferred embodiment of the invention, the lower passage window(s) have an oblong or elongated shape, the lower edge(s) being the lengthwise edge(s) and extending along a peripheral edge of the outer surface of the base body.

[0013] Preferably, the peripheral edge along which the lower edges of the lower windows extend is defined by a plurality of circular arc sections, in particular four, distributed uniformly angularly along the periphery, each circular arc having its concavity facing upwards, and a corresponding plurality, in particular four, of edge sections forming flats, in particular rectilinear horizontal sections, arranged alternately with the circular arc sections.

[0014] Preferably, the cross-section or area, measured perpendicular to the Z axis, of at least one lower window is larger than the cross-section or area of ​​the at least one upper window associated with it.

[0015] Preferably the ball forming the basic body is a truncated sphere on top, in particular along a section plane parallel to the equatorial plane, in particular over a range of longitudes between 60° to 70° and 90°.

[0016] Preferably, the plate-shaped posterior element is concave with its concavity facing downwards, in particular in the form of a spherical cap, in particular having a radius of curvature substantially equal to the radius of the spherical part of the truncated sphere.

[0017] According to a preferred embodiment, the two materials respectively for the base body and the rear element, are based on the same material, in particular thermoplastic, in particular polyethylene (PE), in particular High Density Polyethylene (HDPE) or Ultra High Molecular Weight Polyethylene (UHMWPE), but having grains of different sizes, in particular between 1.0 mm and 1.5 mm for the base body and less than 1.1 mm for the rear element.

[0018] By way of example, a preferred embodiment of the invention will now be described. referring to the drawings, in which:

[0019] Figure 1 is a perspective view from above of an implant according to one embodiment of the invention;

[0020] Figure 2 is a top view of the implant of Figure 1;

[0021] Figure 3 is a side perspective view of the implant of Figures 1 and 2; and

[0022] Figure 4 is a sectional view of Figure 1.

[0023] The figures show an orbital implant according to the invention. The implant comprises a main or basic body 1 consisting of a ball substantially in the shape of a truncated sphere made of a porous and biocompatible material promoting cell colonization and therefore on the one hand the gripping of the ball in position when it is implanted in the eyeball, after enucleation and / or evisceration, and on the other hand the gripping of the oculomotor muscles with the implant.

[0024] In the application, the point of the implant intended to be the most rearward or posterior is defined as being the most superior point (as shown in the figures) and the vertical axis from bottom to top, in particular in the figures, is the anterior-posterior or front-rear axis.

[0025] The ball 1 is truncated in its upper part, in particular over a range of upper longitudes extending from approximately 60° to 90°. A cavity 3 with a flat bottom parallel to the equatorial plane and hollowed out towards the inside of the ball is defined on the top of the truncated ball, being delimited by an inner peripheral lateral wall 4 whose upper edge is defined by four circular arc sections distributed uniformly angularly around the cavity, each circular arc extending over approximately 80° to 85° with its concavity facing upwards, and by four edge sections 5 forming rectilinear horizontal flats arranged alternately with the circular arc sections and which extend, measured along the peripheral edge, each over approximately 5 to 10°.

[0026] On the other hand, this implant comprises an element 2 in the form of a curved plate with through windows made of a non-porous and preferably colonizable material. The plate 2 is curved with its concavity facing downwards and is fixed to the base body 1, in particular by overmolding. This fixing by overmolding is carried out by four tabs 6 of the plate at the level of the flats 5 of the side wall.

[0027] The plate 2 is curved with its concavity facing the cavity 3 so as to be at a distance from the bottom of the cavity delimited by the wall 4. The plate 2 and the upper edge of the wall 4 together delimit four lower through-windows 7 of substantially oblong or elongated shape, the respective lower edges of greater length of which are defined by the arcuate edge sections of the upper edge of the wall 4, which are therefore distributed uniformly around the periphery of the wall 4, while the upper long edges 8, substantially rectilinear, are delimited and defined by plate 2.

[0028] Furthermore, there are formed in the plate 2, between the upper edges 8 of the lower windows 7 and the upper or rear pole 10, four upper windows 9 in the form of right triangles whose respective 90° apexes each point towards the rear upper pole 10. Each through window 9 has a lower edge 11 parallel to the upper edge 8 of a respective lower window 7 and two substantially rectilinear edges 12, 13 originating from this lower edge 11 and meeting at the respective 90° apex of the triangle, close to the pole 10.

[0029] When a meridian M, namely a quarter circle, is drawn along the outer surface of the implant between the upper or posterior pole P and the equatorial plane E of the ball which intersects or passes through an upper window 9, then this meridian also intersects or passes through an associated lower window 7 which is directly below the window 9 along this meridian M. Preferably, the converse is also true.

[0030] The radius of the sphere, which is also the radius of the ball, can be between 5 mm and 12 mm.

[0031] The dimensions of the lower windows are such that a greatest dimension in length (measured in the horizontal direction) may be between 6 mm and 7 mm and a greatest dimension in width (measured along a meridian) may be between 1.5 mm and 2.5 mm.

[0032] The dimensions of the upper windows are such that a greatest dimension in length (measured in the horizontal direction) may be between 3 mm and 4 mm and a greatest dimension in width (measured along a meridian) may be between 2 mm and 2.5 mm.

[0033] The radius of the arcuate edge sections of the upper edge of the wall 4 may be between 1 mm and 2 mm, while the length (measured in the horizontal direction) of the intermediate flats 5 interfacing with the tabs 6 of the plate 2 may be between 3 mm and 4 mm, and the height of the wall 4 in the vertical direction at these flats may be between 2 mm and 3 mm, so that the fixing interface between a tab of the plate and the base body may be between 6 mm2 and 12 mm2.

[0034] To manufacture the implant, it is possible in particular to produce the plate-shaped element 2 and the truncated ball separately, for example by molding with molds of suitable shape, then the two elements are placed in a mold to mold them together, with the interposition of a part whose volume corresponds to the space that it is desired to obtain between the two parts.

[0035] The base body may in particular be made of high-density porous polyethylene, while the window plate 2 may also be made of HDPE, but however with a grain size different from the grain size of the HDPE used for the first element. In fact, a grain is chosen for ball 1 which is such that the HDPE is porous, while the grain of the HDPE chosen for plate 2 is such that plate 2 is not porous but colonizable. Thus, when the assembly is placed again in a mold and plate 2 is overmolded to ball 1, good fixation is obtained by fusion of the grains at the level of the tab-flats interface, the grains being certainly of different sizes but having between them a good affinity of materials which can therefore be well linked intimately in contact with each other.

[0036] Obviously, other manufacturing methods can be provided, and in particular other methods for connecting the two elements together, for example by gluing, welding or the like.

[0037] In addition, other materials can be chosen for the ball as for the plate, in particular for the ball hydroxyapatite (HA), preferably natural but also synthetic, porous aluminum oxide, porous zirconium, porous polyurethane and any other biocompatible porous material capable of fibrovascular colonization.

[0038] For the plate, in addition to non-porous polyethylene, hydroxyapatite (HA), preferably natural but also synthetic, aluminum oxide, zirconium, polyurethane and any other biocompatible material can also be used.

Claims

Claims

1. Orbital implant of substantially spherical shape intended to replace an eyeball after enucleation and / or evisceration consisting of a base body (1) made of a porous material, in particular which promotes colonization by the organism, and a posterior or rear element (2) with through windows covering a part of the base body, the posterior element comprising a plurality of through windows (7) for the passage of suture threads for suturing the oculomotor muscles in and out of the space defined between the base body and the posterior element, characterized in that the posterior element (2) with windows (7) is fixed to the base body, at least one window, preferably the plurality of windows (7), in particular four windows (7), having a respective edge, in particular a respective lower edge, at least partly defined and delimited by the base body.

2. Implant according to claim 1, characterized in that the respective edge at least partly defined and delimited by the basic body is a lower edge.

3. Implant according to claim 2, characterized in that one or more lower through-windows have an oblong or elongated shape, the lower edge(s) being the lengthwise edge(s) and extending along a peripheral edge of the outer surface of the base body.

4. Implant according to claim 3, characterized in that the peripheral edge along which the lower edges of the lower crossing windows extend is defined by a plurality of circular arc sections, in particular four, distributed uniformly angularly along the periphery, each circular arc having its concavity facing upwards, and a corresponding plurality, in particular four, of edge sections forming flats, in particular rectilinear horizontal sections, arranged alternately with the circular arc sections.

5. Implant according to one of claims 1 to 4, characterized in that the orbital implant comprises at least one first lower through-window, which extends over a first lower range of longitudes, and at least one second upper window, which extends over a second upper range of longitudes, and there is at least one meridian extending from the equator to the upper pole that passes through or passes through both the lower and upper windows.

6. Implant according to claim 5, characterized in that the lower range of longitudes and the upper range of longitudes are distinct from each other, i.e. do not overlap, for example the first range being equal to [60°, 70°] and the second range being equal to [75°, 85°].

7. Implant according to one of claims 1 to 6, characterized in that at least one through window has a triangular shape, one point of which is oriented towards the upper pole of the implant.

8. Implant according to claim 7, characterized in that the at least one triangular-shaped crossing window is an upper window.

9. Implant according to one of the preceding claims, characterized in that the basic body is a sphere truncated on top, in particular along a section plane parallel to the equatorial plane, in particular over a range of longitudes between 60° to 70° and 90°.

10. Implant according to one of the preceding claims, characterized in that the plate-shaped posterior element is concave with its concavity facing downwards, in particular in the form of a spherical cap, in particular having a radius of curvature substantially equal to the radius of the spherical part of the truncated sphere.

11. Implant according to one of the preceding claims, characterized in that the two materials respectively for the basic body and the posterior element, are based on the same material, in particular thermoplastic, in particular polyethylene (PE), in particular High Density Polyethylene (HDPE) or Ultra High Molecular Weight Polyethylene (UHMWPE), but having grains of different sizes, in particular between 1 mm and 1.5 mm for the basic body and less than 1.1 mm for the posterior element.

12. An implant according to one of the preceding claims and suture threads passing through the plurality of through windows into and out of the space defined between the base body and the posterior element.

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