Abstract
Purpose :
To assess the effectiveness and safety of riboflavin–ultraviolet type A (UVA) rays induced cross-linking (CXL) of corneal collagen in reducing progression of keratoconus and in improving visual acuity in pediatric patients with progressive keratoconus
Methods :
Prospective nonrandomized open study comprised 58 eyes of 58 patients, aged between 8 to 16 years affected by documented progressive keratoconus, were treated by combined riboflavin–UVA rays collagen CXL. Radiant energy was 3 mW/cm2 or 5.4 joule/cm2 for a 30-minute exposure at 5 cm from the corneal apex. A complete ophthalmologic examination (uncorrected visual acuity [UCVA], best spectacle-corrected visual acuity [BSCVA]) was performed before treatment, at 3 months, 6 months, 1, 2 and 3 to 4 years afterwards. Patients had corneal topography, anterior segment ocular coherence tomography and Scheimpflug imaging
Results :
The mean age was 12.5 ± 1.9 years, 46 males. Ocular allergy was presented in 86.2% and family history of keratoconus in 31.0%. UCVA and BSCVA improvements were statistically significant (P<0.001) throughout the entire postoperative period (Figure 1). Mean ± SE baseline flattest keratometry (K1), steepest keratometry (K2), average keratometry and maximum keratometry were 47.95 ± 0.60 D, 53.29 ± 0.74 D, 50.42 ± 0.65 D and 60.16 ± 1.02 D respectively. At 3 to 4 years, these readings were 47.03 ± 0.63 D, 51.70 ± 0.76 D, 49.24 ± 0.66 D and 58.25 ± 1.05 D respectively, all statistically significant. Topographic corneal astigmatism showed reduction at 1 year after CXL, being similar at 2 and 3 to 4 years (p<0,001). There was a decrease in thinnest pachymetry in both exams, Visante OCT and Pentacam HR, between baseline and 3 months after CXL (mean change 21.45 mm, p<0,001). The variation in thinnest pachymetry between 3 months and 1, 2 and 3 to 4 years was not statistically significant and the mean thinnest pachymetry remained decreased from baseline (Table 1). Corneal haze was the main complication, presented in 50% at 3 months, remained similar at 6 months and 1 year, and decreased at 2 years (p<0,001).
Conclusions :
Cross-linking showed to be safe and effective in pediatric patients in 3-4 years follow-up. A good functional response in visual acuity and keratoconus stability was obtained after corneal CXL during this period.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.