Effect of Corneal Cross-Linking on the Tear Osmolarity in Progressive Keratoconus Patients

This study was conducted to assess the effect of corneal cross-linking on tear film osmolarity in patients with progressive keratoconus using the TearLab device.
66 eyes of 66 patients including 40 men and 26 women with age range of 15 to 35 years old with progressive keratoconus who were candidates for corneal cross-linking surgery, were evaluated in this prospective study. These indicated patients for corneal cross-linking surgery had no history of eye or systemic disease associated with ocular manifestations. They hadnt worn contact lenses since 3 weeks before study and also they hadnt used drugs (effective on tear layer) or contact lenses for 6 months after surgery except their treatment period. Tear osmolarity was measured preoperatively and 6 months after surgery using the TearLab device. After all, data analysis was performed by descriptive and analytical statistical methods.
The mean Osmolarity before the corneal cross-linking surgery is 303.82±15.50 mOsm/L and after the surgery is 306.64±14.49 mOsm/L. There is no significant difference in tear film Osmolarity before and after the corneal cross-linking (P=0.192).
Corneal cross-linking had no significant impact on tear film osmolarity in progressive keratoconus patients and we can’t consider dry eye as a side effect of corneal cross-linking.