Variable pulsed light is less painful than light-emitting diodes for topical photodynamic therapy of actinic keratosis: a prospective randomized controlled trial

BACKGROUND: Photodynamic therapy (PDT) of actinic keratosis (AK) using methylaminolaevulinate (MAL) is an effective and safe treatment option, but the procedure is painful. OBJECTIVES: To evaluate the efficacy and pain associated with variable pulsed light (VPL), a prospective, randomized, controlled split-face study was performed. METHODS: Topical MAL-PDT was conducted in 25 patients with AK (n = 238) who were suitable for two-sided comparison. After incubation with MAL, irradiation was performed with a light-emitting diode (LED) (50 mW cm(-2); 37 J cm(-2)) vs. VPL (80 J cm(-2), double pulsed at 40 J cm(-2), pulse train of 15 impulses each with a duration of 5 ms, 610-950 nm filtered hand piece) followed by re-evaluation up to 3 months. RESULTS: The pain during and after therapy was significantly lower with VPL irradiation [t (d.f. = 24) = 4.42, P < 0.001]. The overall mean +/- SD infiltration and keratosis score at 3 months after treatment was 0.86 +/- 0.71 (LED system) vs. 1.05 +/- 0.74 (VPL device) (no statistically significant difference; P = 0.292). Patient satisfaction following both treatment modalities did not significantly differ at the 3-month follow up (P = 0.425). CONCLUSIONS: VPL used for MAL-PDT is an efficient alternative for the treatment of AK that results in complete remission and cosmesis equivalent to LED irradiation but causes significantly less pain.