Table 1. Characteristics of 6 randomized controlled trials included in analysis.
(K, keratometry; D, diopter; SE, spherical equivalent; epi-off, conventional CXL; epi-on, transepithelial CXL).
| Study (Year) |
Location (Follow-up) |
CXL Protocol | Inclusion criteria of progressive keratoconus | Postoperative Treatment | Postoperative Complications | Age (epi-off/epi-on) |
No. eyes (epi-off/epi-on) |
Male (epi-off/epi-on) |
UVA irradiance (mW/cm2)/ UVA wavelength (nm) |
Jadad score |
|---|---|---|---|---|---|---|---|---|---|---|
|
Mastropasqua et al. (2013) |
Italy (12 months) |
Epi-off CXL: riboflavin for 15mins, UVA irradiation for 30mins Epi-on CXL: riboflavin for 30mins, UVA irradiation for 30mins |
Mean central K-change of ≥1.5D in 3 topographies in 6 months | NA | NA | 23/23 | 20/20 | NA/NA | 3/370 | 2 |
|
Nawaz et al. (2015) |
India (6 months) |
Epi-off CXL: riboflavin for 30mins, UVA irradiation for 30mins Epi-on CXL: riboflavin for 30mins, UVA irradiation for 30mins |
>1D steep K-change in 12 months or >0.5D in 6 months | Topical moxifloxacin, predacetate drops. Oral nonsteroidal anti-inflammatory drugs and soft bandage contact lens applied in epi-off CXL group. |
NA | 23.95/22.35 | 20/20 | 15/17 | 3/765 | 3 |
|
Rossi et al. (2015) |
Italy (12 months) |
Epi-off CXL: riboflavin for 30mins, UVA irradiation for 30mins Epi-on CXL: riboflavin and UVA irradiation for 30mins |
Worsen topographic, pachymetric, or aberrometric in 6 months | Topical tobramycin, dexamethasone phosphate, lubricating drops and therapeutic contact lens in epi-off group, no contact lens and corticosteroid drops were instilled in epi-on group. | No ocular or systemic adverse events were observed. | 30.4/28 | 10/10 | 5/6 | 3/370 | 2 |
|
Soeters et al. (2015) |
Netherlands (12 months) |
Epi-off CXL: riboflavin for 30mins, UVA irradiation for 30mins Epi-on CXL: riboflavin for 30mins, UVA irradiation for 30mins |
Max/steep/mean K-change and/or topographic cylinder-change ≥0.5D in 6–12 months | Antibiotic drops, preservative-free artificial tears, nonsteroidal anti-inflammatory drops (first week), and topical steroids (from second week) were applied. Oral pain medication and bandage lensapplied in epi-off group. | Herpes simplex keratitis, sterile infiltrate, epithelial healing problems in epi-off group. No adverse events in epi-on group. 23% detected progression in epi-of group, and 14% retreated by epi-off CXL. |
24/24 | 26/35 | 19/28 | 3/NA | 4 |
|
Bikbova et al. (2016) |
Russia (24 months) |
Epi-off CXL: riboflavin for 30mins, UVA irradiation for 30mins Epi-on CXL: riboflavin for 10mins by iontophoresis, UVA irradiation for 30mins |
Steep K-change >1D in manifest cylinder, or >0.5D in manifest SE | Antibiotics and topical steroids for epi-off group. Corticosteroid for epi-on group. |
Slight stromal edema and epithelial healing problem in epi-off group. No adverse events in epi-on group. One patient detected progression in epi-on group. |
30/28 | 73/76 | NA/NA | 3/370 | 3 |
|
Lombardo et al. (2016) |
Italy (6 months) |
Epi-off CXL: riboflavin for 30mins, UVA irradiation for 30mins Epi-on CXL: riboflavin for 5mins by iontophoresis, UVA irradiation for 9mins |
Max K-change of ≥1D in 12 months | Ofloxacin, sodium hyaluronate, and fluorometholone acetate for both groups. Bandage lens applied in epi-off group. |
Tearing and photophobia was reported in epi-off group. | 29.4/31.05 | 12/22 | 8/18 | 3/370 for epi-off CXL 10/370 for epi-on CXL |
4 |
|
Lombardo et al. (2017) |
Italy (12 months) |
Epi-off CXL: riboflavin for 30mins, UVA irradiation for 30mins Epi-on CXL: riboflavin for 5mins by iontophoresis, UVA irradiation for 9mins |
Max K-change of ≥1D in 12 months | Ofloxacin, sodium hyaluronate, and fluorometholone acetate for both groups. Bandage lens applied in epi-off group. |
Cornea scars was reported in epi-off group. | 29.4/31.0 | 12/22 | NA | 3/370 for epi-off CXL 10/370 for epi-on CXL |
4 |