System for Correcting an Irregular Surface of a Cornea and Uses Thereof

Abstract

Provided are systems and methods for correcting a corneal surface irregularity in a subject. The system generally comprises a infrared laser, for example, and infrared laser and a laser control unit, a corneal contacting unit, a gel solidifying unit and an electronic device tangibly storing algorithms to operate the units. In the methods, a polymerizable or thermo-reversible gel or polymerized resin is applied to the anterior corneal surface and solidified as a layer over the cornea. A first correcting cut is lasered into the stroma of an applanated cornea, the gel layer is then removed and a second correcting cut is lasered in the stroma of the applanated cornea. The lenticule formed intrastromaly by the first and second correcting cuts is removed such that the cornea has a corrected corneal curvature.

What is claimed is: 
     
         1 . A system for smoothing an irregular corneal surface of an eye, comprising:
 a laser unit comprising a pulsed laser emitter;   a laser control unit in electronic communication with the laser unit;   a corneal contacting unit in electronic communication with the laser control unit positionable proximate to a corneal surface;   a gel solidifying unit configured to initiate a polymerization or a thermo-reversible solidification of a gel composition; and   an electronic device comprising a processor and a memory tangibly storing an algorithm comprising processor-executable instructions to operate said units.   
     
     
         2 . The system of  claim 1 , wherein the laser emitter is configured to pulse laser radiation within a femtosecond range with a frequency of about 10 Hz to about 500 kHz. 
     
     
         3 . The system of  claim 1 , wherein the laser control unit is configured to control a duration, positioning and intensity of the emitted pulsed laser radiation. 
     
     
         4 . The system of  claim 1 , wherein the corneal contacting unit comprises:
 a first contact element having a concave contacting surface removably contactable with an anterior corneal surface with the gel composition applied thereon;   a second contact element having a concave contacting surface removably contactable with the anterior corneal surface without the gel applied thereon; and   a vacuum applicator disposed on the second contact element configured to produce a curvature of the anterior corneal surface corresponding to the concave contacting surface.   
     
     
         5 . The system of  claim 4 , wherein when a mean corneal index is about 1.4 Diopters, a difference of a corneal refractive index between the cornea and a solidified gel composition is less than about 0.5 Diopter. 
     
     
         6 . The system of  claim 1 , wherein the gel solidifying unit comprises:
 an ultraviolet light emitter configured for triggering a polymerization of a polymerizable gel composition,   a cooling unit configured for solidifying a thermo-reversible gel composition by cooling;   a liquid emitter configured to apply a catalyst on a solidified polymerized resin;   or a combination thereof.   
     
     
         7 . The system of  claim 6 , wherein the gel solidifying unit further comprises an applicator configured to apply the gel composition between the anterior corneal surface and the contacting surface of the corneal contacting unit. 
     
     
         8 . The system of  claim 1 , wherein the polymerizable gel comprises polyurethane methacrylate (PUMA). 
     
     
         9 . The system of  claim 1 , wherein the polymerizable gel comprises a polyester and a catalyst Methyl Ethyl Ketone Peroxide (MEKP). 
     
     
         10 . The system of  claim 1 , wherein the polymerizable gel is a hydrogel. 
     
     
         11 . The system of  claim 1 , wherein the thermo-reversible gel composition comprises a soluble collagen solution. 
     
     
         12 . The system of  claim 11 , wherein the collagen is porcine collagen, bovine collagen or a combination thereof. 
     
     
         13 . The system of  claim 1 , wherein the algorithm comprises processor-executable instructions to identify a curvature to achieve a final corrected corneal curvature. 
     
     
         14 . A method for performing a surgical procedure to correct a defect in eyesight of a subject, comprising the steps of:
 forming a solidified gel layer of a minimum thickness over an anterior corneal surface of an eye via the system of  claim 1 ;   lasering a first correcting surface cut on the cornea through the solidified gel layer;   removing the solidified gel layer;   contacting the anterior corneal surface of the eye with a second contact element;   applying a vacuum to form a second curvature defined by the contacting surface of the second contact element to the anterior surface of the cornea;   lasering a second surface cut when the vacuum is applied, said second surface cut intersecting the first correcting surface cut such that a lenticule is formed on the cornea; and   removing the lenticule from the cornea to form a corrected corneal curvature thereby correcting the defect in eyesight of the subject.   
     
     
         15 . The method of  claim 14 , wherein the forming a solidified gel layer step comprises:
 delivering via an applicator a minimum amount of a polymerizable gel, a polymerized resin or a thermo-reversible gel onto the corneal surface;   positioning a first contact element on the cornea such that the gel interfaces with a concave contacting surface of the first contact element and the anterior corneal surface of the eye; and   irradiating the polymerizable gel layer with ultraviolet radiation or cooling the thermo-reversible gel or chemically modifying the polymerized resin, thereby solidifying the gel.   
     
     
         16 . The method of  claim 15 , wherein prior to the positioning step, the method comprises:
 applying an algorithm to identify a first curvature corresponding to the first surface cut and a second curvature corresponding to the second surface cut;   selecting a first contact element having a contacting surface curvature corresponding to the first curvature; and   selecting a second contact element having a contacting surface curvature corresponding to the second curvature.   
     
     
         17 . The method of  claim 16 , further comprising:
 applying the algorithm to configure a laser to cut the cornea to produce a first cut surface with a curvature corresponding to the first curvature of the selected first contact element and a second cut surface with a curvature corresponding to the second curvature of the selected second contact element.   
     
     
         18 . The system of  claim 14 , wherein the lasering steps comprise:
 selecting a duration, positioning and intensity of laser radiation; and   pulsing the laser radiation within a femtosecond range with a frequency of about 10 Hz to about 500 kHz to produce the first and second cut surfaces.