Fractional erbium: YAG laser‐assisted photodynamic therapy for facial actinic keratoses: a randomized, comparative, prospective study

Background Photodynamic therapy ( PDT ) with methyl aminolevulinate ( MAL ) is effective for treating multiple actinic keratoses ( AK s). Ablative fractional laser ( FL ) creates vertical channels that may facilitate MAL delivery and improve PDT response. Objective To evaluate the efficacy of FL ‐assisted PDT ( FL ‐ PDT ) in treating facial AK s in Korean patients. Methods A prospective randomized non‐blinded trial initially evaluated 271 facial AK s in 45 patients. All patients underwent one session of MAL ‐ PDT using a red light‐emitting diode lamp at 37 J/cm 2 , and 23 patients with 135 AK lesions were randomly assigned to pre‐treatment with a 2940‐nm ablative fractional erbium:Yag laser. Patients were followed up at 1, 2 and 4 weeks and every month until 6 and 12 months post‐treatment. Response, adverse events, cosmetic outcome and patient satisfaction were documented. Finally, a total of 236 facial AK s in 40 patients were enrolled and analysed in this study. Results FL ‐ PDT was significantly more effective than MAL ‐ PDT at treating all AK grades (86.9% vs. 61.2%; P  <   0.001). The efficacy of FL ‐ PDT was most pronounced in treating Olsen grade III AK s (69.4% vs. 32.5%; P  =   0.001). FL ‐ PDT also showed a lower lesion recurrence rate than MAL ‐ PDT (9.7% vs. 26.6%; P  =   0.004). Excellent or good cosmetic outcome was reported in >90% cases. Erythema and hyperpigmentation intensities were higher in the FL ‐ PDT group ( P  >   0.05). Side‐effects were more frequent in the FL ‐ PDT group, but these were mild and well tolerated ( P  >   0.05). Conclusion FL ‐ PDT is effective for treating AK s, especially moderate‐to‐thick lesions.