Method and apparatus for the delivery of photo-chemical (cross-linking) treatment to corneal tissue

Abstract

Systems and methods for delivering and infusing formulations containing riboflavin or its analogues, or other ophthalmic formulations, into corneal tissue are disclosed. Systems and methods are further disclosed to cross-link the corneal tissue through exposure to UVA irradiation. The systems and methods for formulation delivery employ micro-needle array delivery devices.

1 . A method of treating ocular tissue comprising:
 providing a treatment apparatus comprising micro-needles; and   delivering a drug formulation to corneal ocular tissue through penetration of micro-needles into the corneal ocular tissue, and   wherein the drug formulation comprises riboflavin,   wherein the delivered formulation is capable of inducing crosslinking of corneal collagen tissue upon exposure to irradiation.   
     
     
         2 . The method of  claim 1 , wherein the riboflavin is delivered through the corneal ocular tissue trans-epithelially and beneath the Bowmans layer into the mid-stroma. 
     
     
         3 . The method of  claim 1 , wherein an auto-injector associated with the micro-needles provides a spring actuated force to press the micro-needles into corneal tissue. 
     
     
         4 . The method of  claim 3 , wherein a suction ring is placed on a surface of the cornea to center the auto-injector on a pupil and stretches and flattens the corneal surface to facilitate penetration of the micro-needles. 
     
     
         5 . The method of  claim 1 , wherein the micro-needles comprise solid micro-needles, hollow micro-needles, dissolvable micro-needles, or a combination thereof. 
     
     
         6 . The method of  claim 1 , wherein the micro-needles deliver at least 10 to 50 μL into the corneal ocular tissue in less than 60 seconds and the formulation diffuses through the stromal region of the cornea in 10 to 20 minutes. 
     
     
         7 . The method of  claim 1 , further comprising delivery of UVA to the corneal ocular tissue to crosslink corneal collagen tissue exposed to the delivered formulation. 
     
     
         8 . A method of treating ocular tissue comprising:
 providing a UVA applicator; and   delivering UVA irradiation from the UVA applicator to corneal ocular tissue exposed to a formulation comprising riboflavin, wherein the UVA irradiation crosslinks corneal collagen tissue exposed to the formulation.   
     
     
         9 . The method of  claim 8 , wherein the UVA applicator delivers a UVA irradiance of 25 to 35 mw/cm2 with a beam of about 8 to 9 mm in diameter. 
     
     
         10 . The method of  claim 8 , further comprising positioning a contact lens assembly over a cornea comprising the UVA applicator. 
     
     
         11 . The method of  claim 8 , wherein the irradiation comprises a UVA beam from the UVA applicator that matches a convex profile of the cornea so that the irradiation is over 80% uniform over its illumination region. 
     
     
         12 . A device for treating ocular tissue comprising:
 a micro-needle array disposed on a concave disk sized to fit over a corneal surface, wherein the micro-needles are configured to deliver formulation into a cornea upon penetration of the micro-needles into the corneal surface.   
     
     
         13 . The device of  claim 12 , further comprising a reservoir connected to the micro-needle array for providing formulation to hollow micro-needles of the micro-needle array. 
     
     
         14 . The device of  claim 13 , further comprising an actuator which forces the formulation from the reservoir into the micro-needle array for delivery into the cornea. 
     
     
         15 . The device of  claim 12 , wherein the micro-needle array comprises micro-needles coated with the formulation which comprises riboflavin. 
     
     
         16 . The device of  claim 12 , further comprising an auto-injector associated with the micro-needles that provides a spring actuated force to press the micro-needle array into corneal tissue. 
     
     
         17 . The device of  claim 16 , further comprising a suction ring for centering the auto-injector on a corneal surface configured to stretch the corneal surface so as to facilitate penetration of the micro-needle array. 
     
     
         18 . A device for treating ocular tissue comprising:
 a contact lens assembly comprising a contact lens that conforms to a corneal surface;   a skirt around the contact lens configured to sit on a region of the sclera surrounding the cornea; and   a UVA applicator associated with the contact lens assembly for providing UVA irradiation through the contact lens into the cornea.   
     
     
         19 . The device of  claim 18 , wherein the UVA applicator is connected to a UVA source external to the contact lens assembly. 
     
     
         20 . The device of  claim 18 , wherein the skirt comprises rubber.