Photodynamic therapy is an exciting technique that uses the effects of light reacting in the presence of oxygen with a photosensitising cream to selectively destroy abnormal skin cells. It has proven to be a very useful technique in dealing with thin skin cancers and pre-cancerous changes, and also has the advantage of giving an excellent cosmetic result. It is now also being adapted for use in acne, sun damaged skin, fine lines and wrinkles.
How is photodynamic therapy performed?
A special photosensitising cream is applied to the area to be treated. It is left on for a period of time ranging from 30 minutes to a few hours, depending on what is being treated. During this time it is important to protect the skin from excessive exposure to light, particularly strong sunlight, with clothing or dressings.
Following this, a selected light, either red or blue light from a light emitting diode (LED), is shone on to the skin for between 8 and 20 minutes. Usually this is not uncomfortable, but when used to treat skin cancers or severe acne it can be uncomfortable for the duration of the LED skin therapy treatment and an air cooler and/or pain relief tablets can reduce this. Sometimes, when being used as a cosmetic treatment, lasers are used as the light source instead.
What care is needed after treatment?
Following the light or laser treatment the skin needs to be protected from sunlight for 24 to 48 hours until the photosensitising cream becomes inactive, as over exposure to sunlight can cause sunburn-like rashes. Following treatment the skin may be red, swollen, crusted and flaky for a few days, then heals leaving smooth skin.
What is Daylight PDT?
Daylight PDT involves applying the porphyrin cream to the skin and then 30 minutes afterwards sitting outdoors in sunshine to activate the cream. One advantage is that the slower, more gradual exposure to the light means that it is less uncomfortable during the procedure. The disadvantage is that it is dependent on the weather and can only be done optimally from April to October.
What is the outcome?
The advantage of this treatment is that it usually produces an excellent cosmetic result and so is also now being developed as a cosmetic treatment. It can also be an effective treatment for acne and enlarged oil glands.