Sarah, our Physician Assistant, discusses the pre-treatment for PDT or Photodynamic Therapy. She explains how the solution of levulon is absorbed into the skin. PDT treats cancerous spots and prevents precancer before it turns to skin cancer. The solution is put on the patient for an hour and a half during which time the solution soaks to the skin. Later during the blue light therapy, the patients skin reacts to the blue light. PDT is a preventative treatment. It treats precancer spots and prevents turning from basal cell carcinoma to squamous cell carcinoma.