Skip to main content

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)

From: Corneal collagen cross-linking epithelium-on vs. epithelium-off: a systematic review and meta-analysis

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
  1. 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
  2. aCombined Placido disk corneal topography and anterior segment optical coherence tomography (Visante Omni, Carl Zeiss Meditec AG)
  3. bScheimpflug imaging analysis (Oculus Pentacam GmbH, Wetzlar, Germany)