Pentacam topographic changes after collagen cross-linking in patients with keratoconus


1 Department of Ophthalmology, Isfahan University of Medical Sciences, Isfahan, Iran

2 Nosocomial Infection Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

3 Medical Students' Research Center, Isfahan University of Medical Sciences, Isfahan, Iran


Background: Corneal cross-linking (CXL) with riboflavin and ultra-violet A is less invasive in comparison with other procedures such as penetrating keratoplasty. Hence, we planned this study to evaluate the efficacy of CXL in disease progression and to compare keratoconus indices before and 1 year after cross-linking by Pentacam.
Materials and Methods: In this prospective clinical trial, we enrolled 37 eyes of 37 patients suffering from keratoconus who were candidates for CXL. All eyes were examined before and one 1 year after surgery with a slit lamp and Pentacam for corneal topography. To compare the mean of each Pentacam parameter and index before and 1 year after the surgery, we used paired t-test.
Results: There were 23 males and 14 females. The mean age was 21.5 years 18-30 years). At the 12 th month examination, the corneal thickness had decreased (P = 0.0068) and the Index of Height Decentration (IHD) had increased (P = 0.016). There were no statistically significant differences in other indices and parameters 1 year after CXL.
Conclusion: Most of the parameters and indices had not changed during 1 year after CXL. The procedure seems to be effective in stopping the disease progression at least for 12 months after surgery.


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