Abstract
Purpose: :
To evaluate the effect of cross-linking with riboflavin and ultraviolet light (C3RUVA) in hen corneas
Methods: :
After mechanical deepithelization, right corneas of 50 lohmann classic hens were crosslinked by application of 0,1% riboflavin-20% dextran solution and exposure to UVA light (360-380 nm, 3 mW/cm2) for 30 minutes. The left fellow control eyes were deepithelized.Time of epithelial closure with fluorescein stain and haze by the Fantes method were evaluated. At different time point, eyes were exenterated and corneal direct transmittance was measured with a scatterometer developed by us. Eyes were fixed for histology and transmission electronic microscopy (TEM) analysis.
Results: :
There were not differences among groups in the time of epithelial closure (48±12 hours) and in the grade of haze that was not observed.C3RUVA corneas presented better values of direct transmittance than deepithelized corneas and statistical significant differences (p<0,05) were observed at 1 week, 1, 3 and 6 months after surgery.The collagen fiber diameter observed by TEM in the C3RUVA corneas, was significantly increased by 15%, compared with the control fellow eyes (p<0,05). Although there were not differences among groups, in others parameters of light microscopy (cell death, proliferation and differentiation)
Conclusions: :
C3RUVA was well tolerated by hen's corneas with a increase in corneal transparency.The improve in the direct light transmittance observed in C3RUVA corneas could be related with the increase in the collagen fiber diameter.
Keywords: cornea: stroma and keratocytes • refractive surgery • radiation damage: light/UV