Bioengineered corneal implant

Abstract

A corneal implant includes an optical element configured to treat refractive errors, a peripheral skirt surrounding the optical element, and a plurality of openings extending through the peripheral skirt. The corneal implant is formed of a clear, flexible, biocompatible elastomer.

Description

Attorney Docket No. 0294-0006W01BIOENGINEERED CORNEAL IMPLANT FIELD OF INVENTION

[0001] The present disclosure is directed towards artificial corneal implants.BACKGROUND

[0002] Over an estimated 500,000 people are diagnosed as needing treatment for corneal blindness every year. Currently, corneal transplantation (keratoplasty) is the recommended course of treatment, as procedures using synthetic comeal implants (keratoprosthesis) face higher rates of failure and host rejection.

[0003] In any case, both the keratoplasty and keratoprosthesis procedures suffer from surgical constraints, inadequate visual outcomes, and, particularly in the case with synthetic implants, lack of implant durability. Presently, biocompatible sutures and / or adhesives are used to secure comeal implants and transplants to the eye of a patient, but these often result in poorly secured implants, visual artifacts, and impaired vision.

[0004] Therefore, what is needed is an improved artificial corneal implant which can simplify the implantation procedure, improve implant durability and retention, and improve visual outcomes. Accordingly, the present disclosure is directed to artificial corneal implants, and methods of implanting and using artificial comeal implants.SUMMARY

[0005] Generally, the present disclosure is directed to an improved artificial corneal implant which is intended to be used for applications in the eye replacing diseased or damaged corneas. Further, the implants are designed, in particular, to be used with mechanical fasteners and / or aided by a corneal cross-linking procedure, in order to shorten procedure times and improve long-term retention compared to present devices.

[0006] The corneal implant has an optical element, and a peripheral skirt surrounding the optical element. The optical element provided may be provided with a size and curvature in order to provide a desired optical effect in the cornea, i.e., treat refractive errors. The peripheral skirt is provided with a plurality of openings which may allow tissue in-growth, fixation with sutures, and / or fixation with mechanical fasteners to secure the implant in the eye.Attorney Docket No. 0294-0006W01

[0007] In some embodiments, the peripheral skirt is further provided with a plurality of tabs, which may also be used to secure the implant in the eye.

[0008] In some embodiments, the plurality of tabs are further provided with tab openings therethrough which may allow the corneal implants to be secured by mechanical fasteners.

[0009] The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the techniques described in this disclosure will be apparent from the description and drawings, and from the claims.

[0010] It is to be understood that the foregoing general description and the following detailed description of the present invention are merely exemplary and explanatory in nature, and are not to be taken in a limiting sense. Rather, they are given solely for the purpose of describing the broad principles of the invention.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] To complete the description and in order to provide for a better understanding of the techniques presented in this application, a set of drawings is provided. The drawings form an integral part of the description and illustrate an embodiment of the present application, which should not be interpreted as restricting the scope of the present application, but just as an example of how the device can be provided or used. The drawings comprise the following figures:

[0012] FIG. 1A depicts a schematic top view of a corneal implant according to embodiments herein.

[0013] FIG. IB depicts a cross-section of the corneal implant of FIG. 1A.

[0014] FIG. 2 depicts a top view of a corneal implant according to embodiments herein.

[0015] FIG. 3 depicts a top view of a corneal implant according to embodiments herein.

[0016] FIG. 4A depicts a top view of a corneal implant according to embodiments herein.

[0017] FIG. 4B depicts a cross-sectional view of the corneal implant of FIG. 4A.

[0018] FIG. 5A depicts a top view of a corneal implant according to embodiments herein.

[0019] FIG. 5B depicts a detailed / close-up view of a tab of the corneal implant of FIG. 5 A.

[0020] FIG. 5C depicts a detailed / close-up view of peripheral skirt openings of the corneal implant of FIG. 5 A.

[0021] FIG. 6 depicts a top view of a corneal implant according to embodiments herein.

[0022] FIG. 7 depicts a top view of a corneal implant according to embodiments herein.Attorney Docket No. 0294-0006W01

[0023] FIG. 8A depicts a top view of a corneal implant according to embodiments herein.

[0024] FIG. 8B depicts a cross-sectional view of the corneal implant of FIG. 8 A.

[0025] FIG. 9 depicts an example embodiment of a mechanical fastener used to secure corneal implants described herein.

[0026] FIG. 10 depicts a cross-section of a human eye with the corneal implant and a mechanical fastener in use.

[0027] FIGS. 11A and 11B depict cross-sections of a cornea of a human eye with the corneal implant and a mechanical fastener in use.

[0028] FIG. 12 depicts a flow chart of a method of selecting a corneal implant for use in a patient.

[0029] FIG. 13 depicts a top view of a corneal implant according to embodiments herein.

[0030] FIG. 14 depicts a cross-sectional view of a corneal implant according to embodiments herein.

[0031] FIG. 15A depicts a top view of a corneal implant according to embodiments herein.

[0032] FIG. 15B depicts a cross-sectional view of the corneal implant of FIG. 15 A.

[0033] FIG. 15C depicts a detailed / close-up, cross-sectional view of a portion of the optical element of the corneal implant of FIG. 15 A.

[0034] FIG 16 depicts a detailed / close-up, cross-sectional view of an example embodiment of placement of a corneal implant in a partial thickness procedure.

[0035] FIG 17 and 18 depict detailed / close-up, cross-sectional views of example embodiments of placement of a corneal implant in a full-thickness procedure.

[0036] Like reference numerals have been used to identify like elements throughout this disclosure.DETAILED DESCRIPTION

[0037] Embodiments disclosed herein are directed to corneal implants with particular constructions and geometries of peripheral skirts and peripheral skirt openings which are designed to simplify the surgical implantation procedure and improve visual outcomes. Preferred embodiments of the invention will be described by way of example, with reference to the above-mentioned drawings showing elements and results according to the present invention.

[0038] The term “corneal implant”, when used in the following description, is with reference to a unitary device which is designed to be surgically implanted into the stroma of a patient’s eye,Attorney Docket No. 0294-0006W01in order to repair visual problems associated with a diseased or damaged cornea. Such implants, according to the embodiments disclosed herein, generally comprise at least an optical element and a peripheral skirt.

[0039] The term “optical element”, when used in the following description, is with reference to a transparent, central element in the corneal implant which functionally replaces a diseased or damaged cornea. Whereas currently available corneal implants are non-refractive, the optical element of the corneal implant described herein is configured to treat refractive errors.

[0040] The term “peripheral skirt”, when used in the following description, is with reference to an annular portion of the implant, surrounding the optical element, and which is configured to be inserted into the stroma of a patient’s eye to retain the implant at the implantation site, and to retain the optical element at the desired position in the cornea.

[0041] The term “openings”, when used in the following description, is with reference to holes which pass all the way through the peripheral skirt and / or tabs of the peripheral skirt. The openings are advantageously provided to be multi-purpose, such that they may allow fluids, oxygen and nutrients to pass through the implant, allow tissues of the eye to grow therethrough, and may also be used for fixation during the implantation procedure.

[0042] The term “corneal cross-linking”, when used in the following description, is with reference to the phenomenon resulting in the formation of collagen fibrils forming chemical bonds amongst tissue layers of the cornea. In the presence of a photochemical reaction releasing singlet oxygen or reactive oxygen species, collagen is stimulated to form chemical bonds. These bonds form both within collagen fibers themselves, increasing the size and strength of individual fibers; and between fibers and lamellae, thus strengthening the stromal lamellae as a whole. Such a photochemical reaction may be induced by the ultraviolet irradiation of a photosensitizer such as riboflavin. Corneal cross-linking can thus be advantageously applied in order to improve the retention of corneal implants.

[0043] The present invention discloses novel constructions of artificial corneal implants which may be advantageously suited for enhanced fixation with mechanical fasteners and / or corneal cross-linking techniques, in order to improve implant retention and corneal implantation procedures generally. Further, the present invention discloses approaches to design features of artificial corneal implants, such as anterior surface geometry and posterior surface curvature, toAttorney Docket No. 0294-0006W01minimize interference with eye function and to create the desired optical power for patient vision refraction needs.

[0044] Retention of the implant at the desired position is critical, as movement of the implant can lead to rings, halos, shadows, lines, or blurriness in the visual field, or full failure of the implant. Embodiments of the invention disclosed herein are designed with critical dimensions and features which improve the long-term retention of the implant in the desired position.

[0045] Referring now to FIG. 1A, a corneal implant 100 according to embodiment herein includes an optical element 101 and a peripheral skirt 102 surrounding the optical element 101. The peripheral skirt 102 includes a plurality of openings 103 extending through the peripheral skirt 102. The plurality of openings 103 are arranged in a first ring of openings 103a and a second ring of openings 103b. Each opening 103 in the first ring of openings 103a is arranged at a first distance R1 from the center of the corneal implant 100. Each opening 103 in the second ring of openings 103b is arranged a second distance R2 from the center of the corneal implant 100, with the second distance R2 being greater than the first distance R1.

[0046] Referring to FIG. IB, a cross-section through the center of the corneal implant 100 is shown. The optical element 101 has an optical outer diameter OD and an optical thickness OT. In the embodiment shown, the optical thickness OT is a constant thickness. However, in other embodiments, the optical element 101 may have a varying thickness. In embodiments, the optical element 101 may have an optical outer diameter OD of approximately 5.7 mm and an optical thickness OT of approximately 0.5 mm. The peripheral skirt 102 has a skirt outer diameter SD and a skirt thickness ST. In the embodiment shown, the skirt thickness SD is constant. However, in other embodiments, the skirt thickness SD may vary. In embodiments, the peripheral skirt 102 may have a skirt outer diameter SD of approximately 9.2 mm and skirt thickness ST of approximately 0.2 mm.

[0047] As shown in FIG. IB, the optical element 101 is curved or arched. For reference, optical element 101 is concave with respect to the native lens of a native eye when the corneal implant 100 is implanted. The peripheral skirt 102 may be a continuation of the curve or arch of the optical element 101 or may be angled with respect to the optical element 101. In the embodiment ofFIGS.1A-1B, each opening 103 includes an opening axis HA therethrough that may be substantially parallel to the optical axis OA, as shown in FIG. IB. However, as described below, in otherAttorney Docket No. 0294-0006W01embodiments, it may be desirable for the opening axes OA to be at an angle other than parallel to the optical axis OA.

[0048] In the embodiment of FIGS. 1A-1B, the plurality of openings 103 in the first ring of openings 103a are evenly spaced circumferentially around the peripheral skirt 102, at the first distance R1 from the center of the optical element 101. The plurality of openings 103 in the second ring of openings 103b are evenly spaced circumferentially around the peripheral skirt 102 at the second distance R2 from the center of the optical element 101. The openings 103 of the first ring of openings 103 a are circumferentially offset from the openings 103 of the second ring of openings 103b such that none of the openings 103 are radially aligned.

[0049] In this example embodiment, there are 16 openings 103 in the first ring of openings 103a and 16 openings 103 in the second ring of openings 103b. In some embodiments, there may be between 10 and 20 openings 103 in the first ring of openings 103a and / or the second ring of openings 103b. In some embodiments, there may be more openings 103 in the first ring of openings 103 a than in the second ring of openings 103b. In other embodiments, there may be fewer openings 103 in the first ring of openings 103a than in the second ring of openings 103b. In embodiments, the first and second distances R1 and R2 may be selected such that the first and second rings of openings 103a / l 03b may be disposed at any radial distance within the peripheral skirt.

[0050] As depicted in FIG. 1 A, the plurality of openings 103 may each have an approximately circular shape and may each have approximately the same diameter. In this example embodiment, the plurality of openings 103 may have a diameter of about 0.4 mm. In some embodiments, the plurality of openings may have a diameter in the range of about 0.2 mm to 0.5 mm. In some embodiments, the openings 103 in the first ring of openings 103 a may have a larger diameter than the openings 103 in the second ring of openings 103b. In some embodiments, the openings 103 in the first ring of openings 103a may have a smaller diameter than the openings 103 in the second ring of openings 103b.

[0051] FIG. 2 depicts a corneal implant 200 according to embodiments herein. Similar to the corneal implant 100, the corneal implant 200 includes an optical element 201 and a peripheral skirt 202 surrounding the optical element 201. A plurality of openings 203 extend through the peripheral skirt 202. In the embodiment of FIG. 2, the plurality of openings 203 are arranged in a first ring of openings 203a and a second ring of openings 203b. Each opening 203 in the first ring of openings 203a is arranged at a first distance R1 from the center of the corneal implant 200. Each openingAttorney Docket No. 0294-0006W01203 in the second ring of openings 203b is arranged a second distance R2 from the center of the corneal implant 200.

[0052] The plurality of openings 203 in the first ring of openings 203a are evenly spaced circumferentially around the peripheral skirt 202, at the first distance R1 from the center of the optical element 201. The plurality of openings 203 in the second ring of openings 203b are evenly spaced circumferentially around the peripheral skirt 202 at the second distance R2 from the center of the optical element 201. The openings 203 of the first ring of openings 203a are circumferentially offset from the openings 203 of the second ring of openings 203b, such that none of the openings 203 are radially aligned. The openings in the corneal implant 200 are elongated slots. The elongated slots may also be described as rectangular with curved circumferential ends. Further, because the elongated slots extend around the peripheral skirt 202, the elongated sides of the slots may be curved circumferentially. The arcuate shape of the openings may provide a larger opening for tissue in-growth.

[0053] In the embodiment of FIG. 2, there are seven openings 203 in the first ring of openings 203a and seven openings 203 in the second ring of openings 203b. In some embodiments, there may be between five and twenty openings 203 in the first ring of openings 203 a and / or the second ring of openings 203b. In some embodiments, there may be more openings 203 in the first ring of openings 203a than in the second ring of openings 203b. In other embodiments, there may be fewer openings 203 in the first ring of openings 203a than in the second ring of openings 203b. In embodiments, the first and second distances R1 and R2 may be selected such that the first and second rings of openings 203a / 203b may be disposed at any radial distance in the peripheral skirt 202.

[0054] FIG. 3 depicts a corneal implant 300 in accordance with embodiments herein. The corneal implant 300 is similar to the corneal implant 200 of FIG. 2 in that the corneal implant includes an optical element 301 and a peripheral skirt 302 with openings 303 disposed therethrough. As in the embodiment of FIG. 2, the openings 303 are elongated slots. In the embodiment of FIG. 3, a third row of openings 303c arranged at a third distance R3 from the center of the optical element 301 is added, as compared to the corneal implant 200. In the corneal implant 300, there are fourteen openings 303 in the first row of openings 303 a, fourteen openings 303 in the second row of openings 303b, and fourteen openings 303 in the third row of openings 303c. Due to the circumference at the first row of openings 303a being smaller than the circumferenceAttorney Docket No. 0294-0006W01at the second row of openings 303b, which is smaller than the circumference at the third row of openings 303 c, and the rows including the same quantity of openings 303, the openings 303 in the first row of openings 303a have a shorter arc length than the openings 303 in the second row of openings 303b and the openings 303 in the second row of openings 303b are have a shorter arc length than the openings 303 in the third row of openings 303c. However, this is not meant to be limiting, and the arc length may be the same or vary in a different manner. Further, in other embodiments, the quantity of openings 303 in each row of openings need not be equal. In other embodiments, the quantity of openings 303 the rows of openings 303a / 303b / 303c may comprise between five and twenty openings 303. In the embodiment of FIG. 3, the openings 303 of the first ring of openings 303a, the second ring of openings 303b, and the third ring of openings 303c are all offset from each other, such that none of the openings 303 are radially aligned.

[0055] FIGS. 4A and 4B depict a corneal implant 400 according to embodiments herein. The corneal implant 400 includes an optical element 401, a peripheral skirt 402 surrounding the optical element 401, and a plurality of tabs 404 extending radially outward from the peripheral skirt 402. The skirt 402 includes a plurality of openings 403 extending therethrough. In the embodiment of FIGS. 4A-4B, the plurality of openings 403 are arranged in a single ring of openings 403.

[0056] In the embodiment of FIGS. 4A-4B, the single ring of openings 403 is spaced a radius R1 from the center of the optical element 401. In this embodiment, the radius R1 may be approximately 4.3 mm. In this embodiment, the radius R1 is such that the ring of openings 403 is spaced a distance DO from an outer edge of the optical element 401. In embodiments, the distance DO may be in the range of about 0.625 mm to about 1.2 mm. It is noted that although the embodiment of FIGS. 4A-4B shows a single row of openings 403, in other embodiments, a plurality of rows of openings may be included. However, in embodiments, the distance DO to the single row of openings 403 or to an inner row of openings if there are a plurality of rows may be at least 0.625 mm. It is believed that such a minimum distance provides for greater strength in the inner portion of the skirt, for improved durability of the corneal implant 400. As discussed above with respect to FIGS. 1A-1B, the opening axis HA of the openings 403 is substantially parallel to the optical axis OA. However, as also discussed above, this is not meant to be limiting, and in other embodiments, it may be desirable that the opening axis HA be at a non-parallel angle with respect to the optical axis OAto minimize halos, shadows, and / or lines in the patient’s vision due to light reflecting from an inner surface of the openings toward the optical axis OA.Attorney Docket No. 0294-0006W01

[0057] In the embodiment of FIGS. 4A-4B, the plurality of tabs 404 extend radially outward from the peripheral skirt 402. In this example embodiment, there are six tabs 404 which are evenly spaced circumferentially around the peripheral skirt 402. As depicted in FIG. 4A, tabs 404 define an outer tab radius RT. In the embodiment shown, the outer tab radius RT may be approximately 6 mm. In the embodiment of FIGS. 4A-4B, the optical element outer diameter OD is about 7.0 mm and the skirt diameter is about 9.0 mm. The peripheral skirt 402 is disposed at an angle 91 relative to the optical axis OA. In the embodiment shown, the angle 01 is approximately 60°. In the embodiment shown, the peripheral skirt 402 has a skirt thickness ST of about 0.28 mm.

[0058] In the embodiment of FIGS. 4A-4B the optical element has a thickness OT of about 0.6 mm, an anterior surface radius of curvature RCA of about 7.6 mm and a posterior surface radius of curvature of about 7.0 mm. However, these dimensions are not meant to be limiting, and ranges for these dimensions, as noted below, may be utilized. In particular, as discussed in further detail below, the anterior surface radius of curvature RCA (also known as the “base curve”) and the posterior surface radius of curvature (also known as the “power”) may be varied to provide multiple corneal implants for selection tailored to a particular patient.

[0059] FIGS. 5A-5C depict another example embodiment of a corneal implant 500. The corneal implant 500 includes an optical element 501, a peripheral skirt 502 surrounding the optical element 501, and a plurality of tabs 504 extending radially outward from the peripheral skirt 502. The peripheral skirt includes openings 503 extending therethrough. In this example embodiment, each of the plurality of tabs 504 include tab openings 505 extending therethrough. Similar to some embodiments described above, the embodiment of FIGS. 5A-5C includes two rows 503a, 503b of openings 503. In this embodiment, the inner row of openings 503a is disposed at a radius R1 of approximately 3.9 mm from the center of the optical element 501, the outer row of openings 503b is disposed at a radius R2 of approximately 4.2 mm from the center of the optical element 501, and the peripheral skirt outer diameter SD is approximately 8.8 mm. However, this is not meant to be limiting, and the features described below with respect to FIGS. 5A-5C may be utilized in any of the embodiments described herein, and features of other embodiments may be used with the embodiment of FIGS. 5A-5C (e.g., there may be fewer or additional rows of openings 503).

[0060] As shown in FIG. 5B, each of the tab openings 505 is an elongated, rounded slot. In particular, each tab opening 505 includes a tab opening length TOL defined between longitudinal ends of the straight portions of the tab opening 505. Each tab opening 505 further includes a tabAttorney Docket No. 0294-0006W01opening width TOW defined as the radial distance between inner and outer edges of the tab opening 505. In a non-limiting example, the tab opening length TOL may be approximately 0.44 mm and the tab opening height TOH may be approximately 0.16 mm. However, this is not meant to be limiting, and the tab opening length TOL and tab opening height TOH may be other values suitable for the purposes described herein. As noted above, in this example embodiment, the tab openings 505 have rounded ends 505a.

[0061] In this example embodiment, the tabs 505 are rounded. Thus, for example, not by way of limitation, the intersection 507 of each tab 505 with the outer edge of the skirt 502 may be curved. For example, and not by way of limitation, the curved intersection 507 may be concave as shown and may have a radius of curvature varying between 0.20 mm to 0.34 mm. Further, in the embodiment shown, an outer edge 508 of each tab 505 may be curved. For example, the outer edge 508 may be concave relative to the center of the corneal implant 500 and may have a radius of curvature of about 0.64 mm. However, this is not meant to be limiting, and other curves may be utilized.

[0062] In this example embodiment, as shown in FIG. 5C, the plurality of openings 503 are elongated, rounded slots. Each of the openings 503 includes an opening length OL defined between longitudinal ends of the straight portions of the opening 503 (i.e., not including the rounded ends). Each opening 503 further includes an opening width OW defined as the radial distance between inner and outer edges of the opening 503. In non-limiting example, the opening length OL may be approximately 0.60 mm and the opening height OH may be approximately 0.18 mm. However, this is not meant to be limiting, and the opening length OL and opening height OH may be other values suitable for the purposes described herein. As noted above, in this example embodiment, the openings 503 have rounded ends 503c.

[0063] FIG. 6 depicts another embodiment of a corneal implant 600 which is substantially similar to the corneal implant 300 described above with respect to FIG. 3. Thus, the corneal implant 600 includes an optical element 601 and a peripheral skirt 602 with openings 603 disposed through the peripheral skirt 602. However, the corneal implant 600 further includes a plurality of tabs 604 extending radially outwardly from the peripheral skirt 602. Further, each of the plurality of tabs 604 includes a tab opening 605 disposed therethrough. In this example embodiment, the tab openings 605 are generally circular in shape. The tab openings 605 may have a diameter suitable for the purposes described herein. In this example embodiment, the tabs 604 do not have a curvedAttorney Docket No. 0294-0006W01outer edge or rounded ends, as described above. Instead, the outer edge and side edges of the tabs 604 are generally linear. Further, the side edges are generally perpendicular to the outer edge and the side edges. In other embodiments, the tabs 604 may be provided with a curved, smooth transition to the peripheral skirt 602.

[0064] FIG. 7 depicts another embodiment of a corneal implant 700 which is substantially similar to the corneal implant 600 of FIG. 6. Accordingly, details of the corneal implant 600 (and of the corneal implant 300) are incorporated into the description of the corneal implant 700. Thus, the corneal implant 700 includes an optical element 701 and a peripheral skirt 702 with openings 703 disposed through the peripheral skirt 702. The corneal implant 700 further includes a plurality of tabs 704 extending radially outwardly from the peripheral skirt 702, with tab openings 705 disposed through corresponding tabs 704. However, in the embodiment of FIG. 7, the tab openings 705 are oval in shape, rather than the circular shape of the tab openings 605. In other embodiments, the tab openings 705 may be slotted, arcuate, or other shapes.

[0065] FIGS. 8A-8B depict another embodiment of a corneal implant 800. The corneal implant 800 includes an optical element 801 and a peripheral skirt 802 surrounding the optical element 801, with the peripheral skirt 802 including openings 803 disposed therethrough, as described in embodiments above. The optical element 801, peripheral skirt 802, and the openings 803 are similar to the embodiments described above, and can be any of the variations described. The corneal implant 800 further includes anchors 804 extending radially outwardly from the peripheral skirt 802. The anchors 804 include barbs 805 that are configured to anchor the corneal implant 800 in the stroma of a native cornea. The anchors 804 may include a pointed or beveled end 806 facing radially outwardly, and the barbs 805 extend radially inwardly and upwardly / downwardly relative to the peripheral skirt 802, as shown in FIG. 8B. Other designs of the anchors 804 and barbs 805 may be utilized that enable the anchors 804 to be inserted into the stroma of the native cornea and engage stromal layers above and below the pocket formed in the stroma as described below. The embodiment of FIGS. 8A-8B shows four anchors 804 distributed evenly around the circumference of the peripheral skirt 802, but this is not meant to be limiting, and fewer or more anchors 804 may be utilized.

[0066] FIG. 13 depicts another embodiment of a corneal implant 1300. Similar to the other embodiments described herein, the corneal implant 1300 includes an optical element 1301 and a peripheral skirt 1302 surrounding the optical element 1301. Although not shown in FIG. 13, theAttorney Docket No. 0294-0006W01corneal implant 1300 may include tabs as disclosed in other embodiments herein. The details of the corneal implant 1300, such as dimensions, radii of curvatures, etc. may be as described with respect to any of the embodiments herein. In the embodiment of FIG. 13, the peripheral skirt 1302 includes openings 1303. However, in the embodiment of FIG. 13, the openings 1303 are in the form of a lattice of openings 1303. The lattice of openings 1303 may be located as described in other embodiments herein. The lattice of openings 1303 maximizes flow of nutrients and oxygen between corneal tissue anterior and posterior to the peripheral skirt 1302.

[0067] FIG. 14 depicts another embodiment of a corneal implant 1400. Similar to the other embodiments described herein, the corneal implant 1400 includes an optical element 1401, a peripheral skirt 1402 surrounding the optical element 1401, and openings 1403 disposed through the peripheral skirt 1403. Although not shown in FIG. 14, the corneal implant 1400 may include tabs as disclosed in other embodiments herein. The details of the corneal implant 1400, such as dimensions, radii of curvatures, materials, etc. may be as described with respect to any of the embodiments herein. In the embodiment of FIG. 14, the openings 1402 are disposed at non-parallel angles with respect to the optical axis OA. In particular, FIG. 14 shows two examples of the opening axis HA of the openings 1402 disposed at non-parallel angles 04 with respect to the optical axis OA. As shown on the left side of FIG. 14, the opening axis HA may be non-parallel to the optical axis OA and angled away from the center of the optical element 1401. As shown on the right side of FIG. 14, the opening axis HA may be non-parallel to the optical axis OA and angled towards the center of the optical element 1401. The angles 04 may be any non-parallel angle. Although the openings 1402 in FIG. 14 are shown with angles 04 towards and away from the center of the optical element 1401, this is merely to show the possible angles, and generally all of the openings 1402 will be angled either towards or away from the center of the optical element 1401, but not both. Having the opening axes HA disposed at non-parallel angles relative to the optical axis OA minimizes reflections from sidewalls of the openings back towards the native lens of the eye.

[0068] FIGS. 15A-15C depict another example embodiment of a corneal implant 1500. The corneal implant includes an optical element 1501 and a peripheral skirt 1502 with a plurality of openings 1503 disposed therethrough. The plurality of openings 1503 are arranged in a first ring of openings 1503a and a second ring of openings 1503b. Each opening 1503 in the first ring of openings 1503a is arranged at a first distance or first radius R1 from the center of the cornealAttorney Docket No. 0294-0006W01implant 1500. Each opening 1503 in the second ring of openings 1503b is arranged a second distance or second radius R2 from the center of the corneal implant 1500. In this embodiment, the first row of openings 1503a is an inner row and the first radius R1 is approximately 3.65 mm from the center of the optical element 1501, the second row of openings 1503b is an outer row and the second radius R2 is approximately 3.83 mm from the center of the optical element 501, and the peripheral skirt outer diameter SD is approximately 9.0 mm. However, this is not meant to be limiting, and the features described below with respect to FIGS. 15A-15C may be utilized in any of the embodiments described herein, and features of other embodiments may be used with the embodiment of FIGS. 15A-15C (e.g., there may be fewer or additional rows of openings 1503).

[0069] In this embodiment, as shown in FIG. 15 A, the plurality of openings 1503 in the first row of openings 1503a each have an approximately circular shape and each have approximately the same diameter of about 0.4 mm. The first distance R1 is measured from the center of the optical element 1501 to the center of each of the plurality of the openings 1503 in the first row of openings 1503a.

[0070] In this embodiment, as shown in FIG. 15 A, the plurality of openings 1503 in the second row of openings 1503b are approximately a rounded triangle shape. Each of the openings 1503 in the second row of openings 1503b includes an opening length OL defined between longitudinal ends of the outermost edge 1506 of the opening 1503 (i.e., not including the rounded ends). The opening length OL may also be described as a circumferential length of the outermost edge 1506 of the opening 1503 in the second row of openings 1503b. Each opening 1503 in the second row of openings 1503b further includes an opening width OW defined as the radial distance between the outermost edge 1506 and an innermost point or apex 1508 of the opening 1503. The second distance R2 is measured from the center of the optical element 1501 to the outermost edge 1506 of each of the plurality of openings 1503 in the second row of openings 1503b. In a non-limiting example, the opening length OL may be approximately 0.80 mm and the opening width OW may be approximately 0.75 mm. However, this is not meant to be limiting, and the opening length OL and opening width OW may be other values suitable for the purposes described herein.

[0071] In this embodiment, as shown in FIG. 15A, there are 16 openings 1503 in the first row of openings 1503a and 16 openings 1503 in the second row of openings 1503b. In other embodiments, the quantity of openings 1503 in each row of openings may be a different number and the quantity of openings 1503 in each row of openings need not be equal.Attorney Docket No. 0294-0006W01

[0072] In this embodiment, the thickness of the peripheral skirt 1502 is tapered, becoming gradually thinner as the distance from the center of the optical element 1501 increases. The inner skirt thickness 1ST, defined as the thickness of the peripheral skirt 1502 closest to the optical element 1501, is greater than the outer skirt thickness OST, defined as the thickness of the peripheral skirt 1502 furthest from the optical element 1501. In this example embodiment, the 1ST may be approximately 0.25 mm and the OST may be approximately 0.18 mm.

[0073] As shown in FIG. 15B-15C, in this embodiment, the optical element 1501 includes an annular tissue capture ledge 1504 (also referred to as a circumferential capture lip or retention flange) that overhangs a more central portion of the peripheral skirt 1502 to define an undercut tissue-receiving region 1505, wherein peripheral corneal tissue, upon implantation, is received beneath the tissue capture ledge 1504 and retained between the tissue capture ledge 1504 and the peripheral skirt 1501 to resist dislodgement or recession from the optic edge of the patient’s eye.

[0074] In this embodiment, the optical element 1501 has an undercut diameter UD defined between innermost edges 1510 of the undercut tissue-receiving region 1505. Further, the undercut tissue-receiving region 1505 has a skirt overhang width SOW, defined between the innermost edge 1510 of the undercut tissue-receiving region and an outermost edge 1512 of the tissue capture ledge 1504, of approximately 0.23 mm. In some embodiments, the SOW may be in the range of 0.1 mm to 0.4 mm.

[0075] In this embodiment, as shown in FIG. 15B, the positioning of the peripheral skirt 1502 against the optical element 1501 is such that the posterior surface 1514 of the optical element 1501 and the posterior surface 1516 of the peripheral skirt 1502 are continuous with one another. This gives the posterior surface of corneal implant 1500 a smooth, continuous surface, enabling corneal implant 1500 to lay on a surface of equal or similar curvature (e.g., a native corneal stromal bed) with full contact when used in a partial-thickness tissue replacement. In other words, the smooth, continuous posterior surface described and shown does not include steps or bumps or similar offsets or protuberances.

[0076] Specific dimensions have been provided in the embodiments described above. However, as explained above, these are not meant to be limiting. Thus, for the dimensions noted, the following ranges may be utilized: the optical element outer diameter OD, approximately 5.2 mm to approximately 7.0 mm; the peripheral skirt outer diameter SD, approximately 8.0 mm to approximately 9.5 mm; the optical element thickness OT, approximately 0.51 mm toAttorney Docket No. 0294-0006W01approximately 0.94 mm; the peripheral skirt thickness ST, approximately 0.14 mm to approximately 0.4 mm; the angle 01 of peripheral skirt relative to the optical axis OAmay be such that the peripheral skirt matches the curvature of the stroma of the eye. A diameter of openings in the peripheral skirt is in the range of approximately 0.2 mm to approximately 0.5 mm. Further, to correct a refractive error range of -10 Diopter (near sightedness) to +6.0 Diopters (far sightedness), for example, the anterior surface radius of curvature RCA is in the range of approximately 6.85 mm to approximately 8.53 mm, or approximately 7.41 mm to approximately 8.25 mm; the posterior surface radius of curvature RCP is in the range of approximately 5.00 mm to approximately 10.50 mm, or approximately 5.50 mm to approximately 8.50 mm.

[0077] Further, in embodiments hereof, the peripheral skirt of the implant contains a plurality of openings. The plurality of openings may comprise between two and forty-two openings. The plurality of openings may be generally arranged in a semi-circle, a ring of openings, two rings of openings, or three rings of openings. In embodiments comprising two or three rings of openings, the openings of one ring may be radially staggered or offset from openings of other rings, or the openings may alternatively be radially aligned. The openings in the peripheral skirt enable tissue ingrowth through the openings to provide secure attachment to the cornea. In particular, as described in more detail below, the peripheral skirt is disposed in the stroma of a native cornea. The openings in the peripheral skirt enable stromal tissue from above and below the peripheral skirt to extend through the peripheral skirt openings to secure the implant to the native cornea.

[0078] The tabs and tab openings described in some of the embodiments enable a fastener to extend through the tabs / tab openings to secure the implant to the native cornea, as described in more detail below.

[0079] In embodiments hereof, the comeal implant may advantageously be formed of a clear, flexible, biocompatible ophthalmic grade elastomer. For example, and not by way of limitation, the comeal implant may be formed of a cross-linked polyisobutylene (xPIB) polymer in a unitary construction. xPIB is a class of polymer that has been found to hold numerous improvements over acrylics and other materials commonly used in corneal implants. xPIBs exhibit enhanced flexibility, and minimal visual artifacts, including less glistening, and less hazing, compared with acrylics and other presently used polymers. A unitary corneal implant composed of xPIB therefore enhances long-term durability and stability of the implant. In another example, and not by way of limitation, the comeal implant may be formed of cross-linked poly(styrene-Z> / oc£-isobutylene-Z> / oc£-styrene)Attorney Docket No. 0294-0006W01(“STBS”). STBS is a biostable thermoplastic elastomer often used for stents and metallic coatings. STBS is particularly suitable for ophthalmic applications due to its combination of being highly inert, biocompatible, and stable.

[0080] Other ophthalmic grade elastomeric materials may also be used. In the example embodiments described above, the materials have a refractive index of about 1.52. Materials with other refractive indexes may be utilized, which may change the dimensions noted above, provided that the artificial corneal implant matches the mechanical properties of the cornea, such as, but not limited to the elasticity, tensile strength, and viscoelasticity thereof. Accordingly, the artificial corneal implants described herein may have a Young’s modulus (measure of elasticity) in the range of about 0.5 MPa to about 1.0 MPa and a tensile strength of about 1.5 MPa to about 2.0 MPa.

[0081] In embodiments, the corneal implant may be formed by injection molding, cast molding, or other methods to form a clear, flexible, biocompatible elastomer in the shapes shown herein. In a non-limiting embodiment, a blank of the corneal implant is formed, such as by injection molding, and features, such as openings, are formed via CNC machining, laser etching, and similar processes. In a non-limiting example, the corneal implant may be formed using materials and techniques described in U.S. Patent Nos. 7,794,498 and 8,585,940, which are incorporated by reference herein in their entirety.

[0082] Surface modification (treatment, texturization, functionalization, or coating) of one or more of the surfaces of the corneal implant may include, for example and not by way of limitation: plasma treatment (e g., radio frequency (RF) plasma, oxygen plasma, nitrogen plasma); UV / ozone treatment; corona discharge; chemical etching; or deposition or grafting of one or more coatings. Coatings may be applied by, for example, UV-initiated reaction, surface-initiated radical polymerization, graft-to or graft-from techniques, silanization, vapor deposition, dip-coating, spray-coating, layer-by-layer assembly, adsorption, or covalent coupling. In some embodiments, the surface modification increases hydrophilicity and / or wettability and may comprise a hydrophilic and / or zwitterionic material, including phosphorylcholine-containing polymers (e.g., 2-methacryloyloxyethyl phosphorylcholine (“MPC”) or copolymers thereof), poly(ethylene glycol) (PEG) and derivatives, poly(2-hydroxyethyl methacrylate) (pHEMA), polyvinylpyrrolidone (PVP), polyacrylamide, hyaluronic acid, heparin, or combinations thereof. In some embodiments, such coatings reduce protein adsorption, cell adhesion, biofouling, inflammation, haze, and / or microbial adhesion while maintaining optical clarity. In otherAttorney Docket No. 0294-0006W01embodiments, the surface modification decreases hydrophilicity (i.e., increases hydrophobicity) and may comprise hydrophobizing chemistries such as fluorinated or alkylated silanes, silicone-containing coatings, or other hydrophobic coatings. Surface treatments and coatings may be provided to improve adhesion or mechanical fixation of the implant, promote stromal and / or epithelial tissue ingrowth, modulate wound healing, enable or enhance corneal cross-linking and / or bonding, improve biocompatibility, reduce friction, tune permeability or diffusion, reduce infection risk, improve optical clarity, and / or achieve other desired effects.

[0083] In operation, the implant may be used according to implantation methods which may include any of the following as steps: anesthetizing the eye in preparation for operation, removing or partially removing the epithelium of the eye, cutting and removing some or all of the diseased or damaged cornea from the eye, forming a pocket in the stroma to receive the peripheral skirt of the implant, positioning the peripheral skirt in the formed pocket, centering the implant in the desired position of the surgical site, inserting mechanical fasteners and / or sutures through openings and / or tab openings in the implant to secure the implant, irradiating the implant or implantation site to induce corneal cross-linking, and resealing the epithelium in place over the implant.

[0084] The implant is configured to be generally held in place in the eye by the peripheral skirt. The stromal layer of the cornea in which the peripheral skirt is placed is an organized layer composed of a stack of many lamellae. The lamellae comprise long collagen fibrils running parallel to each other, and approximately parallel to the surface of the epithelium. Thus, the stromal layer can be understood as a stack of horizontal layers largely made up of collagen fibers.

[0085] The peripheral skirt, therefore, will sit in the formed pocket in the stroma, generally parallel to the collagen fibers of the tissue, and holding the implant in place. Once in the desired position, the implant may be further secured by mechanical fixation of the implant itself, such as insertion of mechanical fasteners through the peripheral skirt, or by suturing the Bowman’s membrane and / or epithelium back in place over the implant, or with dissolvable glues.

[0086] In embodiments of the invention, the implant may be further secured with a mechanical fastener inserted into at least one of the openings of the peripheral skirt and / or the tabs of the peripheral skirt. In embodiments of the invention, the implant may be further secured by inducing corneal cross-linking in and around the openings of the peripheral skirt. In some embodiments, the implant may be further secured in place by a combination of the aforementioned techniques.Attorney Docket No. 0294-0006W01

[0087] Fig. 9 depicts a mechanical fastener 900 that can be used to secure a corneal implant according to embodiments described herein. The mechanical fastener 900 includes a shaft portion 910 and a head portion 920. The mechanical fastener 900 is defined by a first end 901 and a second end 902, and has a central longitudinal axis LI. The mechanical fastener 900 has an overall height Hl extending from the first end 901 to the second end 902.

[0088] The shaft portion 910 is generally cylindrical, having a diameter DI and a height H2. The shaft portion 910 further includes a plurality of barbs 912 and an insertion bevel 914. The insertion bevel 914 is formed at an angle 93 relative to the orthogonal plane of the central longitudinal axis LI of the shaft portion 910.

[0089] The head portion 920 extends from the shaft portion 910 to the first end 901 of the mechanical fastener 900 and has a height H3. The height H3 of the head portion 920 is equivalent to the overall height Hl of the mechanical fastener 900, less the height H2 of the shaft portion 910. The head portion 920 shares the diameter DI of the shaft portion 910 where the head portion 920 intersects the shaft portion 910, and the head portion 920 has a larger diameter D2 at the first end 901 of the mechanical fastener 900.

[0090] Embodiments of the implants described herein may be advantageously suited for use with a mechanical fastener according to FIG. 9. For example, in some embodiments of the implants described herein, the plurality of openings and / or plurality of tab openings may have a diameter of approximately 0.4 mm. Furthermore, in embodiments of the mechanical fastener 900, the diameter D2 of the head portion 920 of the mechanical fastener 900 may be approximately 0.5 mm, and the diameter DI of the shaft portion 910 of the mechanical fastener 900 may preferably be approximately 0.33 mm. In such cases, the plurality of openings or plurality of tab openings are advantageously configured for use with such mechanical fasteners. Accordingly, the plurality of openings and / or plurality of tab openings in a corneal implant may be selected such that a shaft portion of a mechanical fastener passes therethrough, while a head portion of the mechanical fastener will abut the peripheral skirt or plurality of tabs. In this manner, embodiments of the corneal implant described herein may be fixed into place, in part, via insertion of mechanical fasteners into any of the plurality of openings and / or the plurality of tab openings.

[0091] However, the mechanical fasteners described herein are not intended to be limiting. Embodiments of the present invention may be used with any mechanical fasteners which are suitable for use with the corneal implant embodiments disclosed herein. Further, as noted above,Attorney Docket No. 0294-0006W01sutures may be utilized to secure the corneal implant instead of or in addition to mechanical fasteners

[0092] FIG. 10 depicts a cross-section of a human eye with the corneal implant 100 of FIG. 1 and a mechanical fastener 900 in use.

[0093] FIG. HA and 11B depict a cross-section of a cornea of a human eye with the corneal implant 100 of FIG. 1 and a mechanical fastener 900 in use. The mechanical fastener may be inserted into one of the plurality of openings 103, until the mechanical fastener 900 abuts the peripheral skirt 102, as depicted in FIG. 11B.

[0094] FIG. 12 shows a method 1200 for selecting a corneal implant for use in a patient. The corneal implant may be a corneal implant such as one of the corneal implants described above, or a similar corneal implant. The corneal implant to be used will be selected among a predetermined number of different corneal implants. For example, in an embodiment, the predetermined corneal implants may have different “base curves” and different “powers”. The “base curve” is the radius of curvature of the anterior or outer surface of the optical element (RCA) of the corneal implant. The variation of “power” of the corneal implant is based on the variation of the radius of curvature of the posterior or inner surface of the corneal implant (RCP), for a given set of radius of curvature of the anterior surface of the optical element (RCA), optical element thickness (OT), and material refractive index (z. e. , the refractive index of the material of the optical element). Thus, for example, the corneal implant may be selected among corneal implants with a quantity of different base curves, a quantity of different powers, and a quantity of different optical elements thicknesses. For example, and not by way of limitation, corneal implants may be made with four (4) different base curves. For each base curve (anterior surface radius of curvature RCA), the power (posterior surface radius of curvature RCP) and the optical element thickness OT may be varied to achieve desired refractive power of the corneal implant. For example, in an embodiment, corneal implants with sixty-five different refractive powers ranging from 6.00D to -10.00D may be utilized with a combination of the anterior surface radius of curvature RCA 0.741 mm, 0.769 mm, 0.797 mm, or 0.825 mm in combination with the posterior surface radius of curvature RCP ranging from between 0.8178 mm to 0.5745 mm and the optical element thickness OT ranging from 0.51 mm to 0.94 mm. However, this is not meant to be limiting, and it may be desirable to have more or fewer than sixty-five corneal implants for the pre-selected quantity of corneal implants.Attorney Docket No. 0294-0006W01

[0095] In a step 1202 of the method 1200, a patient’s eye biometry and pre-surgical vision are measured. The patient’s eye biometry includes, but is not limited to, eye length (distance from eye’s front surface to retina), curvature of front surface of the eye, curvature of back surface (retina) of the eye, eye thickness (distance from front surface to back surface of the eye), and power of the crystalline lens of the eye. In embodiments of the method 1200 to cure corneal blindness, without necessarily correcting for refractive error, the corneal implant is selected to achieve normal eyelid movement and normal eye film breakup time. In such embodiments, closely matching the corneal implant anterior radius to the pre-surgical anterior radius is desired. Thus, in the step 1202, the pre-surgical corneal radius may be measured by Keratometry devices such as Keratometers, or photokeratoscopy devices. In other embodiments in which refractive error is corrected, in the step 1202 of the method 1200, in addition to measuring eye biometry, the pre-surgical vision is measured / obtained. The patients’ pre-surgical vision may be obtained by the patient’s whole eye refraction records, if available. If not available, the patient’s pre-surgical vision may be measured for whole eye refraction by refraction devices such as Phoropters, or Optical trial lens set, or Retinoscopy if these refraction devices cannot be used. Further, if whole eye refraction cannot be measured by the above instruments, then the patient’s eye biometry may be measured by instruments such as ultrasound instruments such as UBM, or optical instruments such as OCT. With the biometry measured data, the whole eye refraction may be estimated by optical modeling, such as optical ray tracing using Zemax software.

[0096] In a step 1204 of the method 1200 the measurements are received by a computer program product. In a step 1206 of the method 1200, the computer program product determines the optimal base curve and power of the corneal implant for the patient. In particular, the optimal base curve of the corneal implant is selected based on the diseased or damaged cornea anterior radius measured in step 1202. Further, the optimal power of the corneal implant is selected based on the whole eye refraction determined in step 1202.

[0097] In a step 1208 of the method 1200, the corneal implant is selected among the predetermined quantity of corneal implants based on the determined optimal base curve and power determined in step 1206. For example, and not by way of limitation, the corneal implant is selected based on the pre-determined quantity of corneal implants with the base curve closest to the optimal base curve and the power closest to the optimal power. In an embodiment, the pre-determined quantity of corneal implants may have refractive power that ranges from +6.00D to -10.00D.Attorney Docket No. 0294-0006W01Further, the anterior surface radius of curvature RCA may range from about 0.741 mm to about 0.825 mm, the posterior surface radius of curvature RCP may range from about 0.8178 mm to about 0.5745 mm, and the optical element thickness OT may range from about 0.51 mm to about 0.94 mm.

[0098] EXAMPLE

[0099] In an example of the method 1200, a patient’s right eye has a diseased cornea. A corneal topography instrument is used to measure an anterior surface map of the eye. The map shows a steep radius of curvature of 7.70 mm and a flat radius of curvature of 7.90 mm, with these two radii of curvature being 90 degrees apart in meridians, indicating that the patient’s right eye has an astigmatic diseased cornea.

[0100] Then, a swept-source optical coherence tomography instrument (SS-OCT) is used to measure the cornea further. In the example, the measurements obtained an anterior corneal surface of 7.80 mm radius of curvature along the 45 degrees meridian from the steep curvature based on the corneal topography measurement, a 6.50 mm radius of curvature of the posterior surface of the cornea along the same meridian, and a corneal thickness of 0.55 mm.

[0101] Based on the above measurements, an optical calculation estimates that the above cornea has a power of 42.30 diopters (that is population average for spherical power), and 1.22 diopters of astigmatic error from anterior cornea (that should be corrected).

[0102] Accordingly, using an artificial corneal implant of xPIB material described above with its given xPIB material refractive index (about 1.52), the artificial corneal implant is selected having a spherical anterior surface radius of curvature of 7.69 mm, a spherical posterior surface radius of curvature of 7.01 mm, and a thickness of 0.60 mm.

[0103] Such an artificial corneal implant corrects the diseased native cornea blindness and provides refractive correction.

[0104] In certain embodiments, a corneal implant may be implanted using a partial-thickness (lamellar) approach in which a corneal bed and a circumferential intrastromal pocket are prepared, the implant is positioned such that an optical element is received in the bed region, the peripheral skirt is received within the intrastromal pocket, and the implant is fixed in place.

[0105] FIG. 16 depicts a partial cross-section of a cornea of a human eye with the exemplary positioning of the corneal implant 1500 of FIG. 15A implanted using a partial -thickness surgical approach, wherein a layer of corneal tissue posterior to the optical element 1501 is maintained.Attorney Docket No. 0294-0006W01FIG. 16 also shows sutures 1518 securing the corneal implant 1500 to the stroma. Although shown with sutures 1518, the corneal implant 1500 may be secured using mechanical fasteners and / or other securing mechanisms, as described above.

[0106] In some embodiments, the procedure may be subsequently converted to a true fullthickness configuration sometime after the implant has been positioned and / or secured and / or healed in place, by removing posterior corneal tissue underlying the optical element 1501 to create a through-opening that communicates with the anterior chamber of the eye.

[0107] FIG. 17 depicts a partial cross-section of a cornea of a human eye with the exemplary positioning of a corneal implant 1500 of FIG. 15A implanted using a full -thickness surgical approach, wherein a layer of corneal tissue posterior to the optical element 1501 may be removed after the implant has sufficiently healed (e.g., stromal tissue has regrown through openings 1503).

[0108] FIG. 18 depicts a partial cross-section of a cornea of a human eye with the exemplary positioning of a corneal implant 100 of FIG. 1 A implanted using a full-thickness surgical approach, wherein a layer of corneal tissue posterior to the optical element 101 is removed prior to the implantation of the corneal implant 100. As depicted in FIG. 18, the layer of corneal tissue is removed prior to implantation in the described full-thickness surgical approach in order to make room for the posterior of the optical element 101 since the posterior surface of optical element 101 is not continuous with the posterior surface of the peripheral skirt 102 in the corneal implant 100 of FIG. 1A. In this embodiment, the corneal tissue can be removed in a stepwise fashion. First, a partial thickness trephination of the central cornea is performed to the desired depth of the intrastromal pocket. The intrastromal pocket may then be formed at this depth, then the remaining thickness of the central cornea is trephined to complete the preparation of the full-thickness approach for the corneal implant 100 of FIG. 1A. Such a process may be performed for similar embodiments which do not have optical element posterior surfaces which are continuous with peripheral skirt posterior surface, such as in FIGS. 4A-4B and 8A-8B.

[0109] More particularly, in some embodiments a partial-thickness corneal bed is formed in the cornea to receive the optical element of the implant. The corneal bed may be created using a mechanical cutting instrument (e.g., a trephine, including a vacuum trephine) and / or using a laser system (e.g., a femtosecond laser). When performed with a laser, the corneal cut may include circular, arcuate, and / or lamellar components, and may optionally form one or more sidewall profdes (e.g., vertical, angled, stepped, undercut, dovetail, or other interlocking geometries). TheAttorney Docket No. 0294-0006W01bed is formed at a depth selected to provide partial-thickness preparation (e.g., about 50% to about 90% of corneal thickness), although other depths may be used depending on anatomy and implant design.

[0110] In some embodiments, an intrastromal lamellar pocket is formed to receive a peripheral skirt of the implant, and may extend circumferentially around the corneal bed (e.g., approximately 360°). The pocket may be formed by manual lamellar dissection using one or more lamellar instruments (e.g., spoon blade, beaver blade, curved spatula / DALK dissector, Melies dissector, Tooke blade), and / or may be formed in whole or in part by a laser system (e.g., a femtosecond laser) configured to create a lamellar plane and / or circumferential channel at a depth selected to accommodate the implant’s peripheral skirt. In some embodiments, implantation positions corneal tissue such that an anterior flap and a posterior flap contact opposing surfaces of the peripheral skirt of the implant.[OHl] The implant is then inserted such that the optical element is positioned at the corneal bed and the peripheral skirt is received in the intrastromal pocket. In some embodiments, the corneal bed and / or pocket are irrigated prior to implant insertion. In some embodiments, an anti-fibrotic agent is applied to the corneal bed prior to implantation (e g., mitomycin C at about 0.1 mg / mL to about 0.3 mg / mL for about 10 to about 120 seconds), followed by irrigation.

[0112] Following placement, the implant is secured in place using one or more fixation members. In some embodiments, fixation includes one or more sutures (e.g., monofilament nylon, optionally placed as simple interrupted sutures, and optionally passed through one or more openings in the implant). In some embodiments, fixation includes one or more mechanical fasteners, such as a barbed fastener, tack, anchor, clip, staple, or rivet, optionally deployed through one or more openings in the implant. Fixation may be performed before, after, or in combination with subsequent procedural steps, depending on surgeon preference and the specific implant configuration.

[0113] Following the implant fixation, a contact lens may be placed on the eye, covering the implant and surrounding corneal tissue, to reduce postoperative complications such as inner eyelid irritation and support healing.

[0114] In embodiments in which the procedure is converted to a true full-thickness configuration, posterior corneal tissue underlying the optical element is removed after the implant is inserted and / or secured. This removal creates a full-thickness opening in the cornea thatAttorney Docket No. 0294-0006W01communicates with the anterior chamber, thereby establishing a full -thickness optical opening aligned with the optical element. In some embodiments, removal of posterior corneal tissue includes removal of posterior stroma, Descemet’s membrane, and corneal endothelium underlying the optical element. The posterior tissue removal may be performed using a laser (e.g., a femtosecond laser) and / or using mechanical cutting instruments (e.g., scissors, blade, punch, trephine, dissector). In some embodiments, the posterior tissue removal is performed after the implant is secured; in other embodiments, it is performed before completion of fixation. In some embodiments, the implant is configured to cover and / or seal the resulting full-thickness opening such that aqueous humor flow through the opening is reduced relative to the absence of the implant.

[0115] These exemplary procedures are provided to illustrate representative implantation workflows and are not intended to be limiting; variations in cutting modality, pocket creation, fixation approach, timing of steps, and tissues removed may be employed while remaining within the scope of the disclosed methods. Further aspects of the disclosed methods are discussed below.

[0116] In some embodiments, a method of implanting a corneal implant in an eye of a patient comprises: forming a partial-thickness corneal bed in a cornea of the eye; forming an intrastromal lamellar pocket in the cornea that extends circumferentially around the corneal bed; inserting the corneal implant such that an optical element of the corneal implant is positioned at the corneal bed and a peripheral skirt of the corneal implant is received within the intrastromal lamellar pocket; and securing the corneal implant in place.

[0117] In some embodiments, in the method of any of the preceding or following embodiments, securing the corneal implant in place comprises using one or more sutures and / or one or more mechanical fasteners to secure the corneal implant.

[0118] In some embodiments, in the method of any of the preceding or following embodiments, forming the parti al -thickness corneal bed comprises cutting the cornea with a trephine. In some embodiments, the trephine is a vacuum trephine.

[0119] In some embodiments, in the method of any of the preceding or following embodiments, forming the partial-thickness corneal bed comprises cutting the cornea with a laser. In some embodiments, the laser comprises a femtosecond laser.

[0120] In some embodiments, in the method of any of the preceding or following embodiments, cutting the cornea with the laser forms at least one of: a circular cut, an arcuate cut, a lamellar cut, or a combination thereof.

[0121] In some embodiments, in the method of any of the preceding or following embodiments, cutting the cornea with the laser forms a sidewall geometry comprising at least oneAttorney Docket No. 0294-0006W01of: a vertical profile, an angled profile, a stepped profile, an undercut profile, a dovetail profile, or an interlocking profile.

[0122] In some embodiments, in the method of any of the preceding or following embodiments, forming the partial-thickness corneal bed comprises cutting to a depth of about 50% to about 90% of corneal thickness.

[0123] In some embodiments, in the method of any of the preceding or following embodiments, the intrastromal lamellar pocket extends about 360 degrees around the corneal bed.

[0124] In some embodiments, in the method of any of the preceding or following embodiments, forming the intrastromal lamellar pocket comprises manually dissecting corneal stroma with a lamellar dissection instrument.

[0125] In some embodiments, in the method of any of the preceding or following embodiments, the lamellar dissection instrument comprises at least one of: a spoon blade, a beaver blade, a curved spatula, a DALK dissector, or a Tooke blade.

[0126] In some embodiments, in the method of any of the preceding or following embodiments, forming the intrastromal lamellar pocket comprises forming at least a portion of the intrastromal lamellar pocket with a laser.

[0127] In some embodiments, in the method of any of the preceding or following embodiments, the laser comprises a femtosecond laser configured to form a lamellar plane and / or a circumferential channel at a depth selected to receive the peripheral skirt of the corneal implant.

[0128] In some embodiments, in the method of any of the preceding or following embodiments, the method further comprises applying an anti-fibrotic agent to the corneal bed prior to inserting the corneal implant.

[0129] In some embodiments, in the method of any of the preceding or following embodiments, the anti-fibrotic agent comprises mitomycin C.

[0130] In some embodiments, in the method of any of the preceding or following embodiments, applying mitomycin C comprises applying mitomycin C at a concentration of about 0.1 mg / mL to about 0.4 mg / mL for about 10 seconds to about 120 seconds, and irrigating the cornea thereafter.

[0131] In some embodiments, in the method of any of the preceding or following embodiments, the method further comprises flushing the corneal bed and the intrastromal lamellar pocket with a sterile irrigating solution prior to inserting the corneal implant.

[0132] In some embodiments, in the method of any of the preceding or following embodiments, securing the corneal implant in place comprises placing the one or more fixation members as one or more sutures.Attorney Docket No. 0294-0006W01

[0133] In some embodiments, in the method of any of the preceding or following embodiments, the one or more sutures are placed as simple interrupted sutures.

[0134] In some embodiments, in the method of any of the preceding or following embodiments, the one or more sutures comprise at least three sutures.

[0135] In some embodiments, in the method of any of the preceding or following embodiments, securing the corneal implant in place comprises passing a suture needle through one or more openings formed in the corneal implant.

[0136] In some embodiments, in the method of any of the preceding or following embodiments, the one or more sutures comprise monofdament nylon.

[0137] In some embodiments, in the method of any of the preceding or following embodiments, the method further comprises burying one or more suture knots in corneal tissue.

[0138] In some embodiments, in the method of any of the preceding or following embodiments, inserting the corneal implant comprises positioning corneal tissue to form an anterior flap and a posterior flap that contact opposing surfaces of the peripheral skirt of the corneal implant.

[0139] In some embodiments, in the method of any of the preceding or following embodiments, the method comprises, sometime after inserting the corneal implant and securing the corneal implant in place, removing corneal tissue located posterior to the optical element such that a full-thickness opening is formed in the cornea underlying the optical element.

[0140] In some embodiments, in the method of any of the preceding or following embodiments, removing corneal tissue comprises removing posterior stroma, Descemet’s membrane, and corneal endothelium underlying the optical element.

[0141] In some embodiments, in the method of any of the preceding or following embodiments, removing corneal tissue is performed after securing the corneal implant in place.

[0142] In some embodiments, in the method of any of the preceding or following embodiments, removing corneal tissue is performed before completing securing the corneal implant in place.

[0143] In some embodiments, in the method of any of the preceding or following embodiments, removing corneal tissue comprises cutting with a mechanical cutting instrument.

[0144] In some embodiments, in the method of any of the preceding or following embodiments, the mechanical cutting instrument comprises scissors, a blade, a punch, a trephine, or a dissector.

[0145] In some embodiments, in the method of any of the preceding or following embodiments, the corneal implant is configured to cover and / or seal the full-thickness openingAttorney Docket No. 0294-0006W01such that aqueous humor flow through the opening is reduced or eliminated relative to the absence of the corneal implant.

[0146] In some embodiments, a method of implanting a corneal implant to create a fullthickness optical opening comprises: forming a partial-thickness corneal bed in a cornea; forming an intrastromal lamellar pocket extending circumferentially around the corneal bed; inserting the corneal implant such that an optical element is positioned at the corneal bed and a peripheral skirt is received within the intrastromal lamellar pocket; securing the corneal implant in place; and removing posterior corneal tissue underlying the optical element to form a full -thickness opening that communicates with an anterior chamber of an eye.

[0147] In some embodiments, in the method of any of the preceding or following embodiments, removing the posterior corneal tissue occurs after inserting the corneal implant and / or after securing the corneal implant in place.

[0148] In some embodiments, in the method of any of the preceding or following embodiments, securing the corneal implant in place comprises using one or more sutures to secure the corneal implant.

[0149] In some embodiments, in the method of any of the preceding or following embodiments, securing the corneal implant in place comprises deploying one or more mechanical fasteners.

[0150] In some embodiments, in the method of any of the preceding or following embodiments, the one or more mechanical fasteners comprise at least one of: a barbed fastener, a tack, an anchor, a clip, a staple, or a rivet.

[0151] In some embodiments, in the method of any of the preceding or following embodiments, deploying the one or more mechanical fasteners comprises placing the one or more mechanical fasteners through one or more openings formed in the corneal implant.

[0152] In some embodiments, in the method of any of the preceding or following embodiments, removing posterior corneal tissue comprises cutting with a laser.

[0153] In some embodiments, in the method of any of the preceding or following embodiments, removing posterior corneal tissue underlying the optical element to form a fullthickness opening that communicates with an anterior chamber of an eye is performed after securing the corneal implant in place.

[0154] In some embodiments, in the method of any of the preceding or following embodiments, removing posterior corneal tissue underlying the optical element to form a fullthickness opening that communicates with an anterior chamber of an eye is performed before completing securing the corneal implant in place.Attorney Docket No. 0294-0006W01

[0155] In some embodiments, in the method of any of the preceding or following embodiments, the full-thickness opening is centered under the optical element.

[0156] In some embodiments, in the method of any of the preceding or following embodiments, the corneal implant covers and / or seals the full-thickness opening such that aqueous humor flow through the opening is reduced relative to the absence of the corneal implant.

[0157] Reference may be made to the spatial relationships between various components and to the spatial orientation of various aspects of components as depicted in the attached drawings. However, as will be recognized by those skilled in the art after a complete reading of the present disclosure, the devices, components, members, apparatuses, etc. described herein may be positioned in any desired orientation. Thus, the use of terms such as “above,” “below,” “upper,” “lower,” “top,” “bottom,” or other similar terms to describe a spatial relationship between various components or to describe the spatial orientation of aspects of such components, should be understood to describe a relative relationship between the components or a spatial orientation of aspects of such components, respectively, as the components described herein may be oriented in any desired direction. When used to describe a range of dimensions and / or other characteristics (e.g., time, pressure, temperature, distance, etc.) of an element, operations, conditions, etc., the phrase “between X and Y” represents a range that includes X and Y.

[0158] For example, it is to be understood that terms such as “left,” “right,” “top,” “bottom,” “front,” “rear,” “side,” “height,” “length,” “width,” “upper,” “lower,” “interior,” “exterior,” “inner,” “outer” and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration. Further, the term “exemplary” is used herein to describe an example or illustration. Any embodiment described herein as exemplary is not to be construed as a preferred or advantageous embodiment, but rather as one example or illustration of a possible embodiment.

[0159] Further, the present disclosure may repeat reference numerals and / or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and / or configurations discussed.

[0160] Similarly, when used herein, the term “comprises” and its derivations (such as “comprising,” etc.) should not be understood in an excluding sense, that is, these terms should not be interpreted as excluding the possibility that what is described and defined may include further elements, steps, etc. Meanwhile, when used herein, the term “approximately” and terms of its family (such as “approximate,” etc.) should be understood as indicating values very near to thoseAttorney Docket No. 0294-0006W01which accompany the aforementioned term. For values given, a deviation of 5% from the exact value should be accepted, because a skilled person in the art will understand that such a deviation from the values indicated is inevitable due to measurement inaccuracies, etc. The same applies to the terms “about” and “around” and “substantially”.

[0161] While specific aspects are described herein, it will be understood that the disclosed devices are capable of further modifications and this application is intended to cover any variations, uses, or adaptations of the aspects.

Claims

Attorney Docket No. 0294-0006W01CLAIMS1. A corneal implant comprising:an optical element, wherein the optical element is configured to treat refractive errors; a peripheral skirt surrounding the optical element; anda plurality of openings extending through the peripheral skirt,wherein the corneal implant is formed of a clear, flexible, biocompatible elastomer.

2. The corneal implant of claim 1, wherein the elastomer is a cross-linked polyisobutylene polymer.

3. The corneal implant of claim 1, wherein the elastomer is cross-linked poly(styrene-Z> / ocA-i sobutyl ene-b lock-sty rene) .

4. The corneal implant of any one of claims 1 to 3, further comprising a plurality of tabs extending radially outward from the peripheral skirt.

5. The corneal implant of claim 4, further comprising a plurality of tab holes extending through the plurality of tabs.

6. The corneal implant of any one of claims 1 to 5, wherein the plurality of openings extending through the peripheral skirt are substantially parallel to an optical axis of the optical element.

7. The corneal implant of any one of claims 1 to 5, wherein the plurality of openings extending through the peripheral skirt are disposed at a non-parallel angle with respect to an optical axis of the optical element.

8. The corneal implant of any one of claims 1 to 7, wherein the peripheral skirt is disposed at an angle of about 60° with respect to an optical axis of the optical element.

9. The corneal implant of any one of claims 1 to 8, wherein an anterior surface of the optical element has a radius of curvature between approximately 6.85 mm and approximately 8.53 mm.Attorney Docket No. 0294-0006W0110. The corneal implant of any one of claims 1 to 8, wherein an anterior surface of the optical element has a radius of curvature between approximately 7.41 mm and approximately 8.25 mm.

11. The comeal implant of any one of claims 1 to 10, wherein a posterior surface of the optical element has a radius of curvature between approximately 5.00 mm and approximately 10.50 mm.

12. The corneal implant of any one of claims 1 to 10, wherein a posterior surface of the optical element has a radius of curvature between approximately 5.50 mm and approximately 8.50 mm.

13. The corneal implant of any one of claims 1 to 12, wherein the optical element includes an undercut tissue-receiving region.

14. The corneal implant of claim 13, wherein an annular tissue capture ledge overhangs a portion of the peripheral skirt to define the undercut tissue-receiving region.

15. The corneal implant of claim 14, wherein the undercut tissue-receiving region has a skirt overhang width between approximately 0.1 mm and approximately 0.4 mm, wherein the skirt overhang width is defined between an innermost edge of the undercut tissue-receiving region and an outermost edge of the tissue capture ledge.

16. The corneal implant of claim 15, wherein the skirt overhang width is between approximately 0.15 mm and approximately 0.3 mm.

17. The corneal implant of any one of claims 1 to 13, wherein a posterior surface of the optical element and a posterior surface of the peripheral skirt are continuous and smooth such that a posterior surface of the corneal implant is smooth and continuous.

18. A method of selecting a corneal implant for use in a patient, the method comprising:receiving data regarding a patient’s eye biometry;determining an optimal base curve, power, and optical thickness of a corneal implant based on the data; andselecting a corneal implant among a predetermined quantity of corneal implants based on the determined optimal base curve, power, and optical thickness.Attorney Docket No. 0294-0006W0119. A method of implanting a comeal implant in an eye of a patient, the method comprising: preparing a comeal bed in a cornea of the eye;forming an intrastromal lamellar pocket in the cornea that extends circumferentially around the corneal bed;inserting the corneal implant such that an optical element of the comeal implant is positioned at the corneal bed and a peripheral skirt of the corneal implant is received within the intrastromal lamellar pocket; andsecuring the comeal implant in place.

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