Photodynamic Therapy

Photodynamic Therapy is a relatively new and exciting type of treatment that has potential medical and cosmetic benefits.  Photodynamic therapy is primarily used to treat certain types of skin cancers or precancerous sunspots but can also be used for rejuvenation of sun damaged skin and in the treatment of acne, rosacea and psoriasis.

How Does it Work?

Photodynamic therapy involves two stages.  Firstly a chemical known as a photosensitiser is applied to the skin.  The photosensitiser is then activated with a light source. 

The photosensitiser is selectively absorbed by cancerous or damaged skin cells.  It is allowed to incubate on the skin for a period of thirty minutes up to three hours.  The light source that is used consists of an LED light.  This has over one thousand small globes that emit light at a precise wavelength.  Two different wavelengths can be used - blue light with a wavelength of 410nm and red light with a wavelength of 630nm.  Blue light is the most potent activator of the photosensitiser but does not penetrate very deeply into the skin.  Red light penetrates more deeply into the skin.  Often both wavelengths will be used for maximum benefit.

What Types of Skin Cancers Can be Treated?

Photodynamic therapy can be used to treat superficial basal cell carcinoma, nodular basal cell carcinoma up to 1mm deep, squamous cell carcinoma in-situ (Bowen's disease) and solar keratoses (sunspots).  Photodynamic Therapy is considered the best treatment for certain skin cancers in particular situations eg. large areas of Bowen's Disease on the lower legs.  It gives a good cosmetic result (better than surgery) and a high cure rate.  It is also now considered the best treatment for field treatment of solar keratoses (sunspots).  Sunspots are potentially precancerous lesions and field treatment refers to treating an entire area eg. face or scalp rather than just isolated lesions.  Photodynamic Therapy gives a superior cosmetic result and cure rate than cryotherapy (freezing).  In addition, it treats the microscopic spots that are invisible to the naked eye.  There is evidence emerging to suggest that this treatment reduces the risk of developing future skin cancers.

What are the Cosmetic Uses?

Photodynamic Therapy can be used for rejuvenation of sun damage skin.  This is similar to a chemical peel but the results are more targeted to the areas of sundamage.  In addition, there is also the medical benefits of increased reduction of sunspots and future skin cancer risk.

Photodynamic Therapy is used in the treatment of inflammatory acne.  The blue light targets proprionibacterium acnes, the germ responsible for causing infection in acne sufferers.  Using the blue light alone without the photosensitiser can improve acne but this improvement is magnified when using the photosensitiser as well.   Photodynamic Therapy has also been used in the treatment of rosacea and psoriasis.

What are the Risks?

This is considered a safe procedure.  However, it can be painful.  Pain is managed by the use of local anaesthetic (Including nerve blocks), oral analgesics and / or injections of pain killers and happy gas. 

Side effects from PDT are due to the treated area being sensitive to light. The photosensitivity usually lasts about 24 to 48 hours. Side effects may include:

• Burning/stinging sensation
• Swelling and redness
• Crusting
• Itchiness
• Peeling and blisters
• Skin infections

The treated skin area may blister and ulcerate as the treated cells die off. This generally takes about one week but can take longer in the treatment of skin cancer.  Although the photosensitiser concentrates in cancerous and damaged cells, it can also make healthy cells more sensitive to light. 

How Much Does it Cost?

Treatement costs vary depending on the size of the area treated, the reason for treatment and the time required under the LED light.  Treatment cost for isolated sunspots start at $100 and increase to $750 for full facial treatment.