Long-pulsed dye laser versus long-pulsed dye laser-assisted photodynamic therapy for acne vulgaris: A randomized controlled trial

Background: Long-pulsed dye laser (LPDL)-assisted photodynamic therapy has been suggested to be superior to laser alone for acne vulgaris but no evidence is available. Objective: To evaluate the efficacy and safety of LPDL alone versus LPDL in photodynamic therapy with methylaminolevulinic acid (MAL-LPDL) for acne vulgaris. Methods: Fifteen patients received a series of 3 full-face LPDL treatments and half-face prelaser MAL treatments; the latter being randomly assigned to the left or right side. Results: Inflammatory lesions were reduced more on MAL-LPDL-treated than on LPDL-treated sides (week 4: 70% vs 50%, P =.003; week 12: 80% vs 67%, P =.004). Noninflammatory lesions reduced similarly. Patient satisfaction was slightly greater with MAL-LPDL versus LPDL treatments (scale 0-10: week 4: 7 vs 6, P =.034; week 12: 8 vs 7.5, P =.034). Fluorescence measurements detected photobleaching with MAL-LPDL (35.3%) and LPDL (7.3%) treatments (P <.001). Erythema, edema, and pustular eruptions intensified from MAL incubation. No patients experienced pigment changes or scarring. Limitations: The sample size was limited. The split-face design in this randomized controlled trial does not allow us to draw conclusions about the efficacy of the LPDL, only about the efficacy of MAL-LPDL compared with LPDL alone. Conclusions: MAL-LPDL is slightly superior to LPDL for the treatment of inflammatory acne.