Table 2.
Mean differences in the main outcomes and adverse events in randomized controlled trials after corneal collagen cross-linking (epi-on vs. epi-off)
| Study or subgroup | Epi-off CXL | Epi-on CXL | ||||
|---|---|---|---|---|---|---|
| Mean ± SD | n (%) | n | Mean ± SD | n (%) | n | |
| Kmax (D) | ||||||
| Lombardo et al. 2019a [48] | − 1.5 ± 4.9 | – | 12 | − 1.0 ± 3.7 | – | 22 |
| Iqbal et al. 2019b [50] | − 1.2 ± 1.0 | – | 91 | 0.9 ± 1.1 | – | 88 |
| Rossi et al. 2015b [60] | − 1.1 ± 2.1 | – | 10 | − 1.1 ± 1.0 | – | 10 |
| Soeters et al. 2015b [61] | − 1.5 ± 2.0 | – | 26 | 0.3 ± 1.8 | – | 35 |
| UDVA (logMAR) | ||||||
| Lombardo et al. 2019 [48] | − 0.3 ± 0.3 | – | 12 | − 0.3 ± 0.4 | – | 22 |
| Iqbal et al. 2019 [50] | − 0.3 ± 0.1 | – | 91 | 0.2 ± 0.1 | – | 88 |
| Rossi et al. 2015 [60] | − 0.1 ± 0.1 | – | 10 | − 0.1 ± 0.1 | – | 10 |
| Soeters et al. 2015 [61] | − 0.1 ± 0.4 | – | 26 | − 0.1 ± 0.4 | – | 35 |
| CDVA (logMAR) | ||||||
| Lombardo et al. 2019 [48] | − 0.0 ± 0.1 | – | 12 | − 0.1 ± 0.1 | – | 22 |
| Al Zubi et al. 2019 [49] | − 0.1 ± 0.1 | – | 40 | − 0.1 ± 0.1 | – | 40 |
| Iqbal et al. 2019 [50] | − 0.2 ± 0.2 | – | 91 | 0.1 ± 0.1 | – | 88 |
| Rush et al. 2017 [55] | − 0.2 | – | 64 | − 0.1 | – | 80 |
| Bikbova et al. 2016 [57] | − 0.0 ± 0.3 | – | 73 | − 0.1 ± 0.5 | – | 76 |
| Rossi et al. 2015 [60] | − 0.1 ± 0.0 | – | 10 | − 0.2 ± 0.1 | – | 10 |
| Soeters et al. 2015 [61] | − 0.1 ± 0.2 | – | 26 | − 0.1 ± 0.21 | – | 35 |
| Higher-order aberrations (µm) | ||||||
| Lombardo et al. 2019 [48] | − 0.1 ± 0.9 | – | 12 | 1.0 ± 1.1 | – | 22 |
| Godefrooij et al. 2017 [54] | − 0.2 ± 0.4 | – | 26 | 0.0 ± 0.5 | – | 35 |
| Comatic aberrations (μm) | ||||||
| Rossi et al. 2015 [60] | − 0.4 ± 1.2 | – | 10 | − 0.7 ± 1.3 | – | 10 |
| Demarcation Line (depth in µm at 1 month) | ||||||
| Bikbova et al. 2016 [57] | 287.0 ± 15.0 | – | 73 | 179.0 ± 18.0 | – | 76 |
| Soeters et al. 2015 [61] | 266.0 ± 64.0 | – | 26 | 0.0 | – | 35 |
| Central corneal thickness (µm) | ||||||
| Lombardo et al. 2019 [48] | 5.0 ± 21.0 | – | 12 | 7.0 ± 27.0 | – | 22 |
| Al Zubi et al. 2019 [49] | 5.4 ± 12.5 | – | 40 | 6.7 ± 15.5 | – | 40 |
| Bikbova et al. 2016 [57] | − 13.0 ± 37.2 | – | 73 | − 6.7 ± 38.6 | – | 76 |
| Rossi et al. 2015 [60] | 1.8 ± 14.6 | – | 10 | − 2.7 ± 37.3 | – | 10 |
| Corneal thinnest point (µm) | ||||||
| Iqbal et al. 2019 [50] | − 8.9 ± 14.9 | – | 91 | − 6.7 ± 9.0 | – | 88 |
| Soeters et al. 2015 [61] | − 4.0 ± 8.0 | – | 26 | 0.0 ± 12.0 | – | 35 |
| ECD (cells/mm2) | ||||||
| Lombardo et al. 2019 [48] | − 30.0 ± 368.0 | – | 12 | − 33.0 ± 309.0 | – | 22 |
| Bikbova et al. 2016 [57] | 20.0 ± 91.0 | – | 73 | 17.0 ± 69.0 | – | 76 |
| Rossi et al. 2015 [60] | − 31.4 ± 66.6 | – | 10 | − 53.0 ± 202.4 | – | 10 |
| Soeters et al. 2015 [61] | − 59.0 ± 284.2 | – | 26 | 11.0 ± 338.9 | – | 35 |
| KC progression | ||||||
| Lombardo et al. 2019 [48] | – | 0 (0.0%) | 12 | – | 2 (9.1%) | 22 |
| Iqbal et al. 2019 [50] | – | 0 (0.0%) | 91 | – | 25 (28.4%) | 88 |
| Bikbova et al. 2016 [57] | – | 0 (0.0%) | 73 | – | 1 (1.3%) | 76 |
| Al Fayez et al. 2015 [59] | – | 0 (0.0%) | 36 | – | 19 (55.9%) | 34 |
| Soeters et al. 2015 [61] | – | 0 (0.0%) | 26 | – | 8 (22.9%) | 35 |
| Delay in epithelial healing | ||||||
| Iqbal et al. 2019 [50] | – | 17 (18.7%) | 91 | – | 0 (0.0%) | 88 |
| Rush et al. 2017 [55] | – | 1 (1.6%) | 64 | – | 0 (0.0%) | 80 |
| Bikbova et al. 2016 [57] | – | 4 (5.5%) | 73 | – | 0 (0.0%) | 76 |
| Soeters et al. 2015 [61] | – | 2 (7.7%) | 26 | – | 0 (0.0%) | 35 |
| Persistent stromal haze | ||||||
| Lombardo et al. 2019 [48] | – | 2 (16.7%) | 12 | – | 0 (0.0%) | 22 |
| Al Zubi et al. 2019 [49] | – | 4 (10.0%) | 40 | – | 0 (0.0%) | 40 |
| Iqbal et al. 2019 [50] | – | 2 (2.2%) | 91 | – | 0(0.0%) | 88 |
| Bikbova et al. 2016 [57] | – | 4 (5.5%) | 73 | – | 0 (0.0%) | 76 |
| Soeters et al. 2015 [61] | – | 1 (3.8%) | 26 | – | 0 (0.0%) | 35 |
| Sterile infiltrates | ||||||
| Soeters et al. 2015 [61] | – | 1 (3.8%) | 26 | – | 0 (0.0%) | 35 |
| Infection | ||||||
| Rush et al. 2017 [55] | – | 1 (1.6%) | 64 | – | 0 (0.0%) | 80 |
| Soeters et al. 2015 [61] | – | 1 (3.8%) | 26 | – | 0 (0.0%) | 35 |
CXL corneal collagen cross-linking; CDVA corrected distance visual acuity; D diopter; ECD endothelial cell density; KC keratoconus; Kmax maximum keratometry; logMAR logarithm of the minimum angle of resolution; n (%) absolute frequency (relative frequency); SD standard deviation; UDVA uncorrected distance visual acuity
aCombined Placido disk corneal topography and anterior segment optical coherence tomography (Visante Omni, Carl Zeiss Meditec AG)
bScheimpflug imaging analysis (Oculus Pentacam GmbH, Wetzlar, Germany)