Daylight-PDT With MAL for AK and Photodamaged Skin

"In the Daylight photodynamic therapy arm the patients will apply a sunscreen to the whole face which is followed by lesion preparation of AKs. Following this, MAL will be applied in a thin layer to the whole face. Within 30 min after MAL application patients expose themselves to daylight for 2 hours.~5 photodynamic therapy treatment sessions (visits 1-5) will be performed within 18 months."

In the control group, cryosurgery as standard reference therapy will be performed at visit 1, and in case of non-cleared or newly occurred AKs at visits 2-5. Cryosurgery of AK lesions will be investigated as standard reference therapy. Single freeze-thaw cryosurgery is performed using an open spraying procedure with liquid nitrogen with nozzle size C. After formation of an ice-ball of the required size, freeze time starts. Freeze time should lie between 5 s and 10 s.