Table 2.
The pre- and postoperative mean values of patient
| Epi-on CXL | Epi-off CXL | P* | |
|---|---|---|---|
| UCVA (logMAR), mean±SD | |||
| Preoperative (n=15) | 0.7±0.3 | 0.7±0.1 | 0.52 |
| 1 month (n=15) | 0.7±0.3 | 0.7±0.2 | 0.51 |
| 3 months (n=15) | 0.6±0.2 | 0.5±0.2 | 0.25 |
| 6 months (n=15) | 0.7±0.2 | 0.6±0.3 | 0.24 |
| 12 months (n=15) | 0.6±0.1 | 0.5±0.1 | 0.27 |
| P† | 0.27 | 0.08 | |
| 18 months (n=15) | 0.6±0.1 | 0.5±0.2 | 0.57 |
| P† | 0.27 | 0.11 | |
| 24 months (n=5) | 0.6±0.1 | 0.5±0.2 | 0.61 |
| 30 months (n=3) | 0.6±0.1 | 0.5±0.2 | 0.63 |
| BCVA (logMAR), mean±SD | |||
| Preoperative (n=15) | 0.5±0.3 | 0.4±0.2 | 0.25 |
| 1 month (n=15) | 0.5±0.3 | 0.4±0.3 | 0.25 |
| 3 months (n=15) | 0.4±0.2 | 0.3±0.2 | 0.40 |
| 6 months (n=15) | 0.4±0.2 | 0.3±0.1 | 0.40 |
| 12 months (n=15) | 0.4±0.2 | 0.2±0.1 | 0.35 |
| P† | 0.04 | 0.02 | |
| 18 months (n=15) | 0.4±0.2 | 0.2±0.1 | 0.35 |
| P† | 0.04 | 0.01 | |
| 24 months (n=5) | 0.4±0.1 | 0.2±005 | 0.38 |
| 30 months (n=3) | 0.4±0.1 | 0.2±0.05 | 0.36 |
| Kmean (D), mean±SD | |||
| Preoperative (n=15) | 50.0±4.4 | 47.7±2.4 | 0.52 |
| 1 month (n=15) | 50.4±3.8 | 48.5±3.1 | 0.65 |
| 3 months (n=15) | 50.4±3.9 | 48.1±3.0 | 0.61 |
| 6 months (n=15) | 50.1±4.0 | 47.4±2.9 | 0.59 |
| 12 months (n=15) | 49.5±3.4 | 46.9±2.7 | 0.04 |
| P† | 0.06 | 0.005 | |
| 18 months (n=15) | 49.5±3.5 | 46.5±2.9 | 0.01 |
| P† | 0.06 | 0.005 | |
| 24 months (n=5) | 49.6±3.1 | 46.4±2.8 | 0.03 |
| 30 months (n=3) | 49.5±2.9 | 46.4±2.8 | 0.04 |
| Kmean (D), mean±SD | |||
| Preoperative (n=15) | 58.0±4.9 | 55.2±3.6 | 0.14 |
| 1 month (n=15) | 58.3±4.4 | 55.5±3.8 | 0.16 |
| 3 months (n=15) | 57.8±4.1 | 54.8±4.1 | 0.10 |
| 6 months (n=15) | 57.4±4.2 | 54.1±3.5 | 0.12 |
| 12 months (n=15) | 57±4.5 | 54±3.4 | 0.13 |
| P† | 0.05 | 0.005 | |
| 18 months (n=15) | 56.9±3.9 | 53.8±4.1 | 0.04 |
| P† | 0.05 | 0.005 | |
| 24 months (n=5) | 57.2±4.2 | 54.1±4.8 | 0.32 |
| 30 months (n=3) | 57.4±3.8 | 54.2±3.6 | 0.05 |
| CCT, mean±SD | |||
| Preoperative (n=15) | 435±36.8 | 453±21.7 | 0.14 |
| 1 month (n=15) | 428±45.2 | 423±44.1 | 0.05 |
| P† | 0.008 | 0.009 | |
| 3 months (n=15) | 434±42.3 | 418±36.2 | 0.04 |
| P† | 0.85 | 0.007 | |
| 6 months (n=15) | 435±39.2 | 416±28.3 | 0.04 |
| P† | 0.87 | 0.01 | |
| 12 months (n=15) | 436±40.1 | 434±29.4 | 0.04 |
| P† | 0.51 | 0.02 | |
| 18 months (n=15) | 434±37.3 | 439±33.2 | 0.02 |
| P† | 0.72 | 0.01 | |
| 24 months (n=5) | 430±36.2 | 440±30.6 | 0.10 |
| 30 months (n=3) | 430±37.2 | 441±31.8 | 0.16 |
*Mann-Whitney U-test, the comparison of Epi-on and Epi-off CXL in terms of reduction of Kmean, Kmax, and CCT, in terms of increase of UCVA and BCVA. †Wilcoxon test, the comparison of pre- and postoperative UCVA, BCVA, Kmean, Kmax, and CCT; at 12 months and at 18 months in Epi-on and Epi-off CXL. n=The number of patients at each follow-up, CCT (μ) (thinnest point)=Central corneal thickness, Kmean=Mean keratometry value, Kmax=Maximum keratometry value, D=Diopter, UCVA=Uncorrected visual acuity, BCVA=Best-corrected visual acuity, SD=Standard deviation, logMAR=Logarithm of the minimum angle of resolution, CXL=Corneal cross-linking, Epi-on CXL=Epithelium-on CXL, Epi-off CXL=Epithelium-off CXL, CXL=Corneal collagen cross-linking