Table 3.
Different protocols for radiation intensity and duration of Ultraviolet A (UV-A) radiation with equal total energy.67,68
| Irradiation Intensity UV-A fluence (365 nm) (mW/cm2) | Irradiation time | Total energy level (mW/cm2) | Riboflavin impregnation |
|---|---|---|---|
| 3 | 30 min (conventional) | 5.4 | Every 2 min for 30 min, then every 5 min during fluence |
| 6 | 15 min | 5.4 | Every 2 min for 20 min |
| 9 | 10 min (ACXL) | 5.4 | Every 2 min for 20 min, then once after 5 min |
| 18 | 5 min (ACXL) | 5.4 | Every 2 min for 20 min, then every 2 min during fluence |
| 43 | 2 min, 40s (ACXL) | 5.4 | Every 2 min for 30 min |
ACXL, accelerated corneal collagen cross-linking; min, minutes; nm, nanometer; mW/cm2, milliwatts per square centimeter.