Evolution of Ultraviolet Delivery: Accelerated and Pulsed Protocols
Modern devices have moved beyond the original "Dresden Protocol," which required thirty minutes of continuous light exposure. By 2026, Accelerated Cross-Linking (A-CXL) is the clinical standard, based on the principle of "reciprocity"—delivering higher power for a shorter duration to achieve the same total energy dose (fluence).
Irradiance Levels: While standard devices used 3 mW/cm², modern accelerated systems can deliver up to 30 mW/cm², reducing the treatment time from half an hour to as little as three minutes.
Pulsed Light Technology: To address the "oxygen depletion" that occurs during high-intensity treatment, 2026 devices often utilize a pulsed beam (e.g., one second on, one second off). This "rest phase" allows oxygen to diffuse back into the corneal stroma, ensuring the chemical reaction remains efficient throughout the procedure and achieving a deeper effect.