Abstract: Objective: To determine the application value of reflectance confocal microscopy in follow-up of actinic keratosis after 5-aminolevulinic acid photodynamic therapy. Methods: RCM scanning was performed in 16 patients with actinic keratosis at 1 month, 3 months and 6 months after 5-aminolevulinic acid photodynamic therapy. Histological examination was performed in patients with tumor tissue found by RCM. Results: RCM regular reexamination was performed in 16 patients, tumor cells were found in 1 case at 1 month after therapy, and tumor cells were found in 2 cases at 3 months after therapy. All 3 patients were diagnosed with actinic keratosis by histological examination again. No tumor cells were found in the other 13 patients after follow-up for 6 months. Conclusions: RCM has important application value in follow-up of actinic keratosis after photodynamic therapy.

Key words: RCM, actinic keratosis, photodynamic therapy