Title of Invention

SKIRTED CENTRAL OPTIC DEVICE

Abstract This present invention relates to Keratoprosthesis, an artificial cornea, and in particular, to an artificial cornea adapted to be safe and successful for long term application and use avoiding problems of extrusion, aqueous leak, retroprosthetic membrane formation and intraocular pressure rise. The artificial cornea of the invention is provided with features directed to promote retention and minimize post operative complications. Advantageously, the artificial cornea would favour attending to chronic corneal inflammatory condition, chemical burns and those with Stevens-Johnson syndrome or ocular pemphigoid and multiple graft failures.
Full Text FIELD OF THE INVENTION
This present invention relates to Kaeratoprosthesis (KPro), an artificial cornea, and in particular, to an artificial cornea adapted to be safe and successful for long term application and use avoiding problems of extrusion, aqueous leak, retroprosthetic membrane formation and intraocular pressure rise. Importantly, the artificial cornea of the invention is provided with features directed to promote retention and minimize post operative complications. Advantageously, the artificial cornea would favour attending to chronic corneal inflammatory condition, chemical burns and those with Stevens-Johnson syndrome or ocular pemphigoid and multiple graft failures.
BACKGROUND ART
The cornea is the clear window at the front of the eye that provides physical protection to the eye and is the part of the eye's focusing power required for sight. Several corneal diseases or trauma leading to opacification of the cornea is a major cause of blindness in the world population. According to the World Health Organisation (WHO) reports Corneal blindness affects more than ten million people world wide.
Corneal transplantation (i.e. penetrating Keratoplasty) which was first performed in 1909 has become the main rehabilitation procedure for such disorders. The successful rate for corneal transplantation has reached 90% for those patients whose ocular conditions are not complicated by factors such as tear deficiency, vascularization, inflammation, stem cell deficiency or uncontrollable intraocular pressure. However, the prognosis of standard corneal transplantation remains poor for patients with severe chronic inflammation of the ocular

SRI KANCHI KAMAKOTI MEDICAL TRUST
surface in which the anterior segment is in very poor condition and may lead to rejection or opacification of a donor cornea.
Keratoprosthesis (KPro) an artificial cornea is used to replace the opacified corneal tissue and provide a clear window for patients with severe corneal diseases. Various forms of such devices have been used for many years with varying degree of success.
Usually, artificial cornea is fixed to the front face of the optical member which usually involves a translucency ingredient without noxiousness and a natural (body) cornea or the same is inserted between the front layer of a cornea and back layer. Importantly, for such purposes the artificial cornea is provided with a support member to hold the optical member. Usually, the most common material used for obtaining artificial cornea include synthetic-resin ingredient such as polymethyl meth acrylate (PMMA) and silicon which have little noxiousness.
None of the Kaeratoprosthesis practiced today can be said to be absolutely successful in the long term and the problems of extrusion, aqueous, retroprosthetic membrane formation and intraocular pressure rise are yet to be solved.
Importantly, for effective application and use of artificial cornea it is important to develop of Kaeratoprosthesis, an artificial cornea, directed to meet the above requisites and would thus further favour attending to chronic corneal inflammatory conditions, chemical burns and those with Stevens-Johnson syndrome or ocular pemphigoid and multiple graft failures.
It is also found that while Kaeratoprosthesis is a possible option to replace opacified corneal tissue and provide a clear window for patients with severe corneal diseases, there have been complexities involving such artificial cornea to treat patients who are unable to retain donor

SRI .KANCHI KAMAKOTI MEDICAL TRUST
corneal transplant. Importantly, the chances of necrosis are found to develop which in turn lead to complexities in anchoring the prosthesis onto the donor eyes with sutures.
Moreover, the artificial cornea is also required to be adapted such as to allow the patients visual potential to be achieved and also favour its suture onto the eye to treat afore discussed condition requiring Kaeratoprosthesis.
OBJECTS OF THE INVENTION
It is thus the basic object of the present invention to provide for Kaeratoprosthesis, an artificial cornea, which would be selectively adapted for use to replace the opacified corneal tissue and provide a clear window for patients with severe corneal diseases and would substantially avoid the complexities and problems associated with corneal transplantation involving the artificial cornea.
Another object of the present invention is directed to the development of the artificial cornea involving selective constitutional features skirt made of Titanium and optic made of PMMA which would be further adapted to be successful in the long term by way of providing for required bio-integration and substantially meeting the problems of extrusion, aqueous leak or retroprosthetic membrane formation or intraocular pressure rise experienced in application of Kaeratoprosthesis.
A further object of the present invention is directed to identifying and providing selecting constitutional features of artificial cornea directed to promote retention, minimize post operative complication like extrusion, aqueous leak and restore vision in patients who can not receive or are unlikely to have a beneficial outcome from a human donor graft.

SRI .KANCHI KAMAKOTI MEDICAL TRUST
Yet another object of the present invention is directed to development of selective artificial cornea for patients such as suffering from chronic corneal inflammatory condition, chemical burns and those with Stevens-Johnson syndrome or ocular pemphigoid and multiplies graft failure.
Yet another object of the present invention is development of Kaeratoprosthesis, which would meet the afore discussed requirements and compatibility and avoid the usual problems associated with allografting and also allow full visual field.
Another object of the present invention is directed to development of artificial cornea involving optical zone which would be sufficiently rigid to avoid optical aberrations and astigmatism from bulking, favour bio-integration (bio-compatible) and favour defense against intraocular infection, ephithereal down growth as well as avoid accompanying symptoms of eye rubbing and minor trauma.
Yet further object of the present invention is directed to development of selective artificial cornea involving artificial material which would be non-toxic and would not degrade in the lifetime of the patients.
Further object of the present invention to develop selective artificial cornea which would reduce the chance of necrosis and allow the prosthesis to be anchored to the donor eye with sutures.
A further object of the invention is directed to provide for selective artificial cornea wherein the optic is adapted to allow the patients' visual potential to be achieved to provide the desired long term comfort to the patient.

SRI .KANCHI KAMAKOTI MEDICAL TRUST
SUMMARY OF THE INVENTION
Thus according to the present invention there is provided an artificial cornea comprising
an anchoring opaque outer skirt obtained of Titanium and a central optic in the form of a collar stud with stepped configuration;
said outer skirt comprising of Titanium plate and dome shaped with a central opening and having a size of 1 lmm to 13mm selectively adapted to support itself on the outside of the cornea on the limbus on the eye ball providing greater stability and absorbing stress generated on the central optic supported with respect to said central opening in said outer skirt, a plurality of large polygonal openings in said skirt adapted to provide nutrition to the tissues above said outer skirt.
In accordance with a preferred aspect of the present invention there is provided an artificial cornea comprising
an anchoring opaque outer skirt obtained of Titanium and a central optic in the form of a collar stud with stepped configuration;
said outer skirt comprising of Titanium plate of 0.1 to 0.2 mm preferably 0.2mm thickness and dome shaped with a central opening defining a collar of 0.5 to lmm preferably 0.9mm width all around and having a size of 11mm to 13mm selectively adapted to support itself on the outside of the cornea on the limbus on the eye ball providing greater stability and absorbing stress generated on the central optic supported with respect to said central opening in said outer skirt, a plurality of large polygonal openings in said skirt adapted to provide nutrition to the tissues above said outer skirt.

SRI .KANCHI KAMAKOTI MEDICAL TRUST
In the above disclosed artificial cornea the support Titanium plate is adapted to be anchored on the eye ball with prolene sutures passed through said multiple large polygonal openings in said skirt.
In accordance with an aspect of the invention, the said skirt is molded to have a radius of curvature 7.5mm. Importantly, the said skirt has fenestrations adapted to allow an intact 0.5 mm skirt in the periphery thereby reducing necrosis and allowing the prosthesis to be anchored on to the donor eye with sutures.
In accordance with another aspect of the invention, the central optic part is selectively obtained of anyone of transparent polymethyl meth acrylate (PMMA), sapphire and glass providing a refractive power adapted to compensate for the eye.
In accordance with a further aspect of the invention, the central optic is in the form of a collar stud with stepped configuration having a radius of curvature of 7.7 mm with the sides stepped with an inner 0.2 mm step adapted to flush with the bore in the skirt and a further 0.5mm step adapted to raise the same above the plane of the skirt.
Preferably, the central optic is in the form of a collar stud with stepped configuration having a bottom face radius of curvature of 7.0 mm to 9.0 mm preferably 7.7 mm with the sides stepped with an inner 0.1 mm to 1.5 mm preferably 0.5 mm step adapted to flush with the bore in the skirt and a further 0.2 mm to 1.0 mm preferably 0.5mm step adapted to raise the same above the plane of the skirt with an outer top face radius of curvature in the range of 5.0 mm to 8.0mm preferably 6.3 mm.

SRI ,KANCHI KAMAKOTI MEDICAL TRUST
The selective artificial cornea in accordance with the invention as disclosed above thus basically includes the skirt made of the titanium plate of 0.2mm. in thickness which is dome shaped with the central opening with a selective collar of 0.9mm. width all around to support the optical part.
The titanium support part is selectively between 11mm. to 13mm. in size. This enables the prosthesis to support itself on the outside of the cornea of limbus on the eye ball providing greater stability and absorbing all the stresses generated on the optical membrane.
The support titanium part is advantageously and selectively further provided with large polygonal openings which favour the provision nutrition to the tissues above the support plate. Moreover the support titanium plate is further adapted to be anchored on the eyeball with prolene sutures passed through multiple large openings provided.
Importantly, the above-disclosed Kaeratoprosthesis is specifically adapted to take care of chronic corneal inflammatory condition, chemical burns and Stevens-Johnson syndrome, ocular pemphigoid and multiple graft failure.
Advantageously, the Kaeratoprosthesis of the invention is found to provide for the required biointegration (bio-compatibility) and allow defence against intraocular infection and / or other discomfort (eye rubbing) / minor trauma and is found to be safe without problems of degradation during the lifetime of the patients.
As clearly apparent from the above, Kaeratoprosthesis of the invention basically comprises of the selective Titanium based anchoring skirt and the central optic selectively obtained so as to favour treating patient who are unable to retain donor corneal transplant. Importantly, the
materials used and the optic features are selectively provided to promote retention and optimizes patients outcome.

SRI .KANCHI KAMAKOTI MEDICAL TRUST
The outer skirt used in the artificial cornea of the invention is an opaque body selectively molded with defined radius of curvature and is adapted to have high potential for bio integration. Importantly, the skirt is provided with fenestrations which are selectively provided to reduce the chances of necrosis and allow the prosthesis to be anchored onto the donor eye with sutures.
The central optic is preferably obtained of transparent of poly methyl meth aery late (PMMA) or sapphire or glass providing an refractive power to compensate for the eye. It is possible in those conditions requiring removal of the lens and other ocular tissues the power of the optic can be modified to compensate for this. The selective optic core is adapted to allow the patients visual potential to be achieved. Advantageously, as discussed hereinbefore the optic in the artificial cornea of the invention is adapted and obtained preferably in the form of a collar stud of stated defined outer radius of curvature and inner radius of curvature and sides stepped and an inner stepped adapted to make it flushed with an corresponding bore in the skirt and a further step which raises it above the plane of the skirt.
The details of the invention, the objects and advantages are explained hereunder in greater details in relation to non-limiting exemplary illustration as per the accompanying figures.
BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
Figure 1 is an illustration of the Titanium skirt of the prosthesis with selective dimension obtained according to an embodiment of the invention;
Figure 2(a) is an illustration of the optic in the form of collar stud with stepped configuration used in the prosthesis according to an embodiment of the invention;

SRI .KANCHI KAMAKOTI MEDICAL TRUST
Figure 2(b) is an illustration of side profile of an integrated prosthesis obtained in accordance with the present invention.
DETAILED DESCRIPTION OF THE DRAWINGS:
Reference is now invited to accompanying figure 1 which illustrates the selective outer Titanium skirt (SK) configuration in the prosthesis according to the present invention. As illustrated in the figure the outer skirt (SK) of the prosthesis is an opaque, dome shaped configuration having 11 mm. diameter and 0.1-0.2 mm. preferably 0.2mm thick skirt made of titanium. The skirt is molded to have radius of curvature of 7.5mm. The central opening of the outer skirt is of 4mm. and defines and collar of 0.5-lmm preferably 0.9mm. height. Importantly, the skirt is further provided with fenestation and intact 0.5mm. skirt in the periphery. This is adapted to reduce the chances of necrosis and allow the prosthesis to be anchored on to the donor eye with sutures. The selective titanium based outer skirt as above is found to have high potential for bio-integration.
Reference is now invited to accompanying figure 2(a) which illustrates the central optic (CO) part in the prosthesis obtained in accordance with present invention having a stepped configuration. As shown in the figure the central optic (CO) part is a transparent poly methyl meth acrylate (PMMA) or sapphire for glass provided a refractive power to compensate for the eye. In such condition requiring removal of the lens and other ocular tissues, the power of the optic can be modified to compensate. The optic core is adapted to allow the patients visual potential to be achieved. The optic is adapted and developed as shown in the figure in the form of a collar stud. Preferably, the collar stud is provided with an outer radius of curvature of 6.0mm. (modified as per refractive status) and an inner radius of curvature of 7.7mm. The sides are stepped with an inner 0.2mm. step which makes it flush with the bore in the skirt and a further 0.5mm. step which raises it above the plane of the skirt.

SRI(KANCHI KAMAKOTI MEDICAL TRUST
Advantageously, the preferred selective titanium plate 0.2 mm in thickness is dome shaped with central opening with a collar of 0.9 mm width all around to support the optical part. The titanium support part is preferably between 11 mm to 13 mm in size. This enables the prosthesis to support itself on the outside of the cornea on the limbus on the eye ball providing greater stability and absorbing all the stresses generated on the optical member. Importantly, the support Titanium part is provided with large polygonal openings which are adapted to function to provide nutrition to the tissues above the support plate. The support Titanium plate is anchored on the eye ball preferably with prolene sutures passed through the multiple large openings provided.
It is thus possible by way of the above invention to provide for Kaeratoprosthesis, an artificial cornea, which would be selectively adapted for use to replace the opacified corneal tissue and provide a clear window for patients with severe corneal diseases and would substantially avoid the complexities and problems associated with corneal transplantation involving the artificial cornea. Advantageously, the present invention is directed to promote retention, minimize post operative complication like extrusion, aqueous leak and restore vision in patients who can not receive or are unlikely to have a beneficial outcome from a human donor graft. The artificial cornea of the invention would enable the patients' visual potential to be achieved to provide the desired long term comfort to the patient.






SRI.KANCHI KAMAKOTI MEDICAL TRUST We Claim:
1. An artificial cornea comprising
an anchoring opaque outer skirt obtained of Titanium and a central optic in the form of a collar stud with stepped configuration ;
said outer skirt comprising of Titanium plate and dome shaped with a central opening and having a size of 11mm to 13mm selectively adapted to support itself on the outside of the cornea on the limbus on the eye ball providing greater stability and absorbing stress generated on the central optic supported with respect to said central opening in said outer skirt, a plurality of large polygonal openings in said skirt adapted to provide nutrition to the tissues above said outer skirt.
2. An artificial cornea comprising
an anchoring opaque outer skirt obtained of Titanium and a central optic in the form of a collar stud with stepped configuration;
said outer skirt comprising of Titanium plate of 0.1 to 0.2 mm preferably 0.2mm thickness and dome shaped with a central opening defining a collar of 0.5 to 1mm preferably 0.9mm width all around and having a size of 1 lmm to 13mm selectively adapted to support itself on the outside of the cornea on the limbus on the eye ball providing greater stability and absorbing stress generated on the central optic supported with respect to said central opening in said outer skirt, a plurality of large polygonal openings in said skirt adapted to provide nutrition to the tissues above said outer skirt.

SRI ,KANCHI KAMAKOTI MEDICAL TRUST
3. An artificial cornea as claimed in anyone of claims 1 or 2 wherein the support
Titanium plate is adapted to be anchored on the eye ball with prolene sutures passed
through said multiple large polygonal openings in said skirt.
4. An artificial cornea as claimed in anyone of claims 1 to 3 wherein the skirt is molded
to have a radius of curvature 7.5mm.
5. An artificial cornea as claimed in anyone of claims 1 to 4 wherein the said skirt has
fenestrations adapted to allow an intact 0.5 mm skirt in the periphery thereby reducing
necrosis and allowing the prosthesis to be anchored on to the donor eye with sutures.
6. An artificial cornea as claimed in anyone of claims 1 to 5 wherein the central optic
part is selectively obtained of a transparent polymethyl meth acrylate (PMMA),
sapphire and glass providing a refractive power adapted to compensate for the eye.
7. An artificial cornea as claimed in anyone of claims 1 to 6 wherein the central optic is
in the form of a collar stud with stepped configuration having a radius of curvature of
7.7 mm with the sides stepped with an inner 0.2 mm step adapted to flush with the
bore in the skirt and a further 0.5mm step adapted to raise the same above the plane of
the skirt.
8. An artificial cornea as claimed in anyone of claims 1 to 6 wherein the central optic is
in the form of a collar stud with stepped configuration having a bottom face radius of
curvature of 7.0 mm to 9.0 mm preferably 7.7 mm with the sides stepped with an
inner 0.1mm to 1.5 mm preferably 0.5 mm step adapted to flush with the bore in the
skirt and a further 0.2 mm to 1.0 mm preferably 0.5mm step adapted to raise the same

. SRI ,KANCHI KAMAKOTI MEDICAL TRUST
above the plane of the skirt with an outer top face radius of curvature in the range of 5 mm to 8 mm.
9. An artificial cornea substantially as herein described and illustrated with reference to the accompanying figures.


Documents:

2048-CHE-2006 FORM-13 01-09-2009.pdf

2048-CHE-2006 FORM-13 01-09-2009.pdf

2048-che-2006-abstract.pdf

2048-che-2006-claims.pdf

2048-che-2006-correspondnece-others.pdf

2048-che-2006-description(complete).pdf

2048-che-2006-drawings.pdf

2048-che-2006-form 1.pdf

2048-che-2006-form 26.pdf

2048-che-2006-form 5.pdf


Patent Number 246644
Indian Patent Application Number 2048/CHE/2006
PG Journal Number 10/2011
Publication Date 11-Mar-2011
Grant Date 08-Mar-2011
Date of Filing 07-Nov-2006
Name of Patentee SRI KANCHI KAMAKOTI MEDICAL TRUST
Applicant Address SATHY ROAD, SIVANADAPURAM, COIMBATORE 641035, TAMILNADU
Inventors:
# Inventor's Name Inventor's Address
1 DR. JAGADEESH KUMAR REDDY C/O SRI KANCHI KAMAKOTI MEDICAL TRUST SATHY ROAD, SIVANADAPURAM, COIMBATORE 641035, TAMILNADU
PCT International Classification Number A61F 1/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA