PhotoDynamic Rejuvenation, also referred to as Photorejuvenation, PhotoDynamic Therapy or PDT, is a process that obliterates abnormal cell tissue by use of a special topical solution called Levulan (or ALA) that is activated by a red or blue light, IPL Fotofacial, or laser. Rosacea, psoriasis, wrinkles and sun damage are all ideal candidates for Light Therapy treatments.