Introduction/Objective. The aim of this study was to evaluate outcome of
corneal collagen cross-linking (CXL) in patients with progressive
keratoconus. Methods. This retrospective single-centered interventional
study included 52 eyes of 41 patients who underwent epithelium-off CXL
procedure at the age > 18 years. Corneal tomography data, uncorrected and
best spectacle-corrected distant visual acuity (UDVA and CDVA, respectively)
were analyzed at baseline and postoperatively over the initial 12 months
period. In addition, the natural course of corneal tomographic changes were
demonstrated at 1, 3, 6, 9 and 12 months after CXL procedure. Results. At
one year mean UDVA improved significantly from 0.15 ? 0.22 (0,3min - log MAR
- 0 max logMAR) at baseline to 0.06 ? 0.09 logarithm of minimum angle
resolution (log MAR) (0,1min log MAR-0 max logMAR) (p = 0.024). Mean CDVA
was 0.45 ? 0.39 0.45 ? 0.39 logMAR (0,8min log MAR- 0 max logMAR) at
baseline and 0.06 ? 0.13 log MAR (1min logMAR-0 max logMAR) at 1-year (p =
0.039). Maximum keratometry showed a significant flattening of 1.36D ? 1.53D
(p = 0.0032) at 1 year after CXL. Minimum keratometry significantly
decreased with a mean change of 1.15 ? 1.20 (p = 0.011). Mean anterior and
posterior best fit sphere (ABFS, PBFS) remained stable during the entire
follow up period. Mean reduction of corneal thickness after CXL was 47 ?
61?m (p = 0.003). At one year, 29 (56%) eyes showed K max regression; 22
(53%), stabilization; and 1 (2%), progression. Spearman correlation
coefficients were calculated to assess the correlation between difference in
preoperative corneal thickness, in PE CT and MCT, ?CT (PE CT-min CT) and
radius difference ?r (r1-r2). Spearman rs > 0.3 proved statistical
significance and correlation. Conclusion. In our study CXL effectively
prevented progression of keratoconus in 98 % of eyes at 1 year, while
improving visual acuity. The effect of CXL can be evaluated at the earliest
after six months; at that time stability of corneal shape was provided
following CXL procedure. The main limitation of this study is small number
of patients included.