Efficacy of Iontophoresis-assisted AFL-PDT in Actinic Keratosis

For AFL pre-treatment, lidocaine/prilocaine (5%) cream (EMLA; Astra Pharmaceuticals, LP, Westborough, MA, USA) was applied to the treatment area under occlusion for 30 min

After the anaesthetic cream was removed, AFL therapy was performed using a 2940-nm Er:YAG AFL (Joule; Sciton Inc., Palo Alto, CA, USA) at 300-550 µm ablation depth, level 1 coagulation, 22% treatment density and a single pulse

Immediately after AFL treatment, an approximately 1-mm-thick layer of MAL (Metvix, PhotoCure ASA, Oslo, Norway) was applied to the lesion and on 5 mm of surrounding normal tissue.

In Group A, ionotophoresis was performed on MAL-applied sites. We used iontophoresis (vitaliont II®, ITC Inc, Korea) with a patch. The active electrode was the anode, and 0.50-mA/cm2 current was applied to each AK lesion for 10 min.

After incubation for 2 (Group A and B) or 3 hours (Group C), the dressing and cream were removed, and the area was cleansed with saline. The area was irradiated with a red light-emitting diode lamp (Aktilite CL 128; PhotoCure ASA, Oslo, Norway) with peak emission at 632 nm, placed 5 cm away from the skin surface, and a total light dose of 37 J/cm-2. All patients wore protective goggles during illumination.