Table 1.
Visual, refractive, tomographic, aberrometric, and densitometric parameters at baseline and 12 months postoperatively in eyes treated with central corneal regularization combined with corneal cross-linking and in eyes treated with corneal cross-linking as a single procedure
| CXL-Plus group (n = 28) |
CXL group (n = 28) |
p-value (CXL-Plus vs. CXL 0) | p1 (CXL-Plus 0 vs. 12) | CXL-Plus group (n = 28) |
CXL group (n = 28) |
p1 (CXL 0 vs. 12) |
p2 (CXL-Plus vs. CXL 12) | |
|---|---|---|---|---|---|---|---|---|
| Baseline | 12 months follow-up | |||||||
| Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | |||||
| Sex(% female) | 28.57% | 14.29% | 0.329 | |||||
| Age(years) | 27.07 (9.14) | 25.82 (9.25) | 0.613 | |||||
| UDVA(logMAR) | 0.70 (0.35) | 0.65 (0.39) | 0.616 | 0.0002 | 0.36 (0.29) | 0.46 (0.37) | 0.067 | 0.265 |
| BSCVA(logMAR) | 0.23 (0.19) | 0.20 (0.18) | 0.547 | 0.006 | 0.10 (0.15) | 0.06 (0.11) | 0.0009 | 0.260 |
| Refractive values | ||||||||
| MRSE (D) | −1.96 (2.76) | −0.92 (1.80) | 0.101 | 0.023 | −0.54 (1.63) | −0.05 (1.87) | 0.082 | 0.301 |
| Manifest Sphere (D) | −0.43 (2.34) | 0.37 (2.08) | 0.182 | 0.118 | 0.41 (1.53) | 1.65 (1.90) | 0.020 | 0.010 |
| Manifest Cylinder (D) | −3.06 (2.24) | −2.57 (2.49) | 0.442 | 0.020 | −1.91 (1.17) | −3.40 (2.11) | 0.184 | 0.002 |
| Corneal Thickness (μm) | 478.82 (20.42) | 470.36 (17.03) | 0.098 | |||||
| Curvature Values | ||||||||
| Cylinder (D) | 3.84 (1.79) | 3.64 (1.88) | 0.685 | 0.240 | 3.24 (1.98) | 4.03 (2.22) | 0.481 | 0.166 |
| K1 (D) | 43.88 (3.19) | 44.68 (1.62) | 0.242 | 0.006 | 41.64 (2.67) | 43.20 (2.29) | 0.007 | 0.023 |
| K2 (D) | 47.71 (3.79) | 48.32 (2.51) | 0.481 | 0.006 | 44.88 (3.63) | 47.23 (3.08) | 0.152 | 0.012 |
| Kmax (D) | 54.41 (5.22) | 54.36 (3.74) | 0.967 | < 0.0001 | 48.57 (4.49) | 53.70 (4.52) | 0.554 | 0.0001 |
| Aberrometric Values | ||||||||
| Cornea Total | ||||||||
| RMS total (μm) | 2.95 (1.03) | 2.62 (0.97) | 0.223 | < 0.0001 | 1.62 (0.82) | 2.72 (1.35) | 0.752 | 0.0005 |
| RMS LOA (μm) | 2.84 (0.99) | 2.52 (0.94) | 0.220 | < 0.0001 | 1.57 (0.80) | 2.61 (1.31) | 0.769 | 0.0007 |
| RMS HOA (μm) | 0.79 (0.30) | 0.71 (0.28) | 0.307 | < 0.0001 | 0.40 (0.19) | 0.73 (0.36) | 0.817 | 0.0001 |
| RMS Coma-like (μm) | 0.75 (0.29) | 0.68 (0.28) | 0.364 | < 0.0001 | 0.31 (0.21) | 0.65 (0.36) | 0.648 | < 0.0001 |
| Anterior corneal surface | ||||||||
| RMS total (μm) | 3.30 (1.17) | 2.97 (1.06) | 0.274 | < 0.0001 | 1.70 (0.93) | 2.98 (1.34) | 0.975 | 0.0001 |
| RMS LOA (μm) | 3.18 (1.12) | 2.85 (1.03) | 0.256 | < 0.0001 | 1.65 (0.92) | 2.88 (1.29) | 0.924 | 0.0001 |
| RMS HOA (μm) | 0.90 (0.34) | 0.81 (0.30) | 0.298 | < 0.0001 | 0.40 (0.21) | 0.79 (0.36) | 0.822 | < 0.0001 |
| RMS Coma-like (μm) | 0.85 (0.33) | 0.76 (0.30) | 0.316 | < 0.0001 | 0.32 (0.22) | 0.72 (0.36) | 0.417 | < 0.0001 |
| Posterior corneal surface | ||||||||
| RMS total (μm) | 0.80 (0.31) | 0.75 (0.26) | 0.516 | 0.692 | 0.83 (0.25) | 0.81 (0.29) | 0.419 | 0.783 |
| RMS LOA (μm) | 0.76 (0.29) | 0.72 (0.26) | 0.589 | 0.675 | 0.79 (0.24) | 0.77 (0.28) | 0.492 | 0.775 |
| RMS HOA (μm) | 0.23 (0.09) | 0.22 (0.07) | 0.527 | 0.662 | 0.24 (0.08) | 0.23 (0.09) | 0.644 | 0.662 |
| RMS Coma-like (μm) | 0.21 (0.09) | 0.19 (0.07) | 0.417 | 0.489 | 0.23 (0.14) | 0.20 (0.08) | 0.318 | 0.350 |
| Densitometric Values | ||||||||
| 0.0–2.0 mm | 19.00 (1.46) | 18.47 (2.04) | 0.269 | < 0.0001 | 24.49 (5.43) | 25.70 (6.89) | < 0.0001 | 0.469 |
| 2.0–6.0 mm | 16.83 (1.08) | 16.41 (2.39) | 0.401 | 0.001 | 18.53 (2.40) | 18.69 (2.65) | 0.001 | 0.814 |
BSCVA= best spectacle-corrected visual acuity; coma-like= primary and secondary coma aberration; CXL= corneal cross-linking; CXL-Plus= central corneal regularization combined with CXL; HOA= higher order aberrations; K1= flattest meridian, K2= steepest meridian, Kmax= steepest radius of anterior curvature; LOA= lower order aberrations; MRSE= mean refractive spherical equivalent; RMS= root mean square; UDVA= uncorrected distance visual acuity. The results are expressed as means (standard deviation). The level of statistical significance was set at p ≤ 0.05. P-value = the difference between CXL-Plus and CXL values at baseline. p1 = the difference within a group between baseline values and postoperative values at 12 months. p2 = the difference between CXL-Plus values and CXL alone values 12 months postoperatively