Refractive, Topographic, Pachymetric, and Aberrometric Analysis After CXL in Pediatric Keratoconus in South Saudi Arabia
Purpose
To report refractive, topographic, pachymetric and aberrometric outcomes 12 months after corneal cross-linking (CXL) in pediatric keratoconus eyes.
Methods
Prospective, nonrandomized, noncomparative multi center clinical study. Forty-eight eyes, aged 9-16 years old, undergoing corneal collagen crosslinking between January 2012 and February 2013, with follow-up period of 1 year; till February 2014. Riboflavin-ultraviolet A (UVA)-induced CXL included instillation of 0.1% riboflavin–20% dextrane solution 30 minutes before UVA irradiation and every 5 minutes for an additional 30 minutes during irradiation. Main outcome measures: Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), spherical equivilant refraction(SE), corneal thickness (Pentacam), sphere and cylinder refraction, topography, and aberrometry, (OPD scan) were evaluated at baseline and at 1, 3, 6, and 12 months follow-up.
Results
Baseline UCVA, BSCVA were 0.17+/- 0.09 and 0.52+/-0.17; 12 month UCVA , BSCVA were 0.27+/- 0.08 and 0.72+/- 0.16, a statistically significant difference (P ‹ 0.05). SE refraction showed significant decrease of 0.41 D. Mean baseline SIM K flattest, steepest and SIM K average were 46.23, 50.13, and 47.89 D; at 12 months, 40.32, 46.31, and 43.01 D; a difference that was significant for all 3 indices (P ‹ 0.05). average pupillary power (APP) changed from 47.50 to 41.04 D at 12 months (P ‹ 0.05) and apical keratometry (AK) from 58.74 to 55.13 D (P ‹ 0.05). For a 3-mm pupil, reduction (P‹0.05) in total, corneal, higher-order, and astigmatic wavefront aberrations. Baseline pupil center pachymetry decreased (P<0.05) to 470.09=/-29.01 µm from baseline values of 490.68+/-30.69 µm. Endothelial cell counts did not change significantly (P >0.13).
Conclusion
Corneal cross-linking seems to be effective in improving UCVA and BSCVA in pediatric eyes with progressive keratoconus by significantly aborting disease progression, reducing corneal APP, AK, and corneal and total wavefront aberrations at 1 year postoperatively.