What is an Actinic Keratosis?
Actinic Keratoses (AKs) are rough, scaly patches on the skin, caused by cumulative excessive exposure to the sun, which can sometimes progress into dangerous skin cancers. Many doctors believe that AKs and squamous cell carcinomas (skin cancer) are really the same condition at different stages of a continuum.
How long has Photodynamic Therapy (PDT) been around?
Photodynamic therapy has been utilized for more than 20 years. It was approved by the Food and Drug Administration for the treatment of Actinic Keratoses in 1999.
What is ALA?
ALA is short for Aminolevulinic acid, which is a clear solution that is applied to the skin during the treatment. ALA occurs naturally in the body and it is involved in the synthesis of hemoglobin. ALA is preferentially absorbed by abnormal precancerous skin cells and therefore causes minimal to no damage to normal tissue.
How does PDT work?
After absorption by the abnormal precancerous cells, ALA is converted to a natural photosensitizer called Protoporphyrin IX (Pp IX). The skin is then illuminated with a visible blue light source and this begins the Photodynamic process of singlet oxygen production. The release of the singlet oxygen from Pp IX destroys the targeted precancerous cells.
What can I expect?
- You will be given a series of two (sometimes three) treatments, about two weeks apart.
- The technician will do an aggressive acetone scrub, using cotton squares, on the area to be treated. Then ALA will be applied and allowed to incubate for 60-90 minutes. After the incubation period, you will wash off the ALA and will then be exposed to visible blue light for approximately 17 minutes, which activates the photosensitizing agent to destroy the targeted precancerous cells.
- Subsequent treatment sessions may need longer incubation times depending on your response and tolerance to redness and peeling.
- After the treatment is completed you must remain completely out of the sun for 24-48 hours because any visible sunlight or ultraviolet exposure can further activate the process and cause an excessive reaction. Sunscreens will NOT protect from visible light, which has the ability to further activate the process and result in excessive reactions.
- You may get a sunburn-like reaction and experience some mild discomfort. Red, chapped, flaking, or peeling skin may continue for 7-10 days after the treatment.
- You will be given more details in the Consent Form and Aftercare Instructions at the time of your first appointment
- If you have a history of cold sores (aka: fever blisters, herpes simplex), you may be given preventative treatment with anti-viral medications to prevent an outbreak.
- You should not undergo photodynamic therapy if you have a history of any photosensitizing condition