Photodynamic therapy is a very safe and effective treatment which has been used in dermatology for many years primarily to treat sun damage and early skin cancers (superficial basal cell carcinomas and squamous cell carcinomas). It can also be used to treat acne in certain patients who cannot tolerate other medications.
At Complete Skin Specialists we have many years of experience using photodynamic therapy. We can modify and tailor this treatment to suit the degree of sun damage and area needing to be treated to get the best results.
It is an excellent option for treating larger areas of sun damage such as
- Sun damaged lips (actinic chelitis)
- Hands and Forearms
- Lower legs
PDT is a very clever approach to removing sun damaged cells which uses a combination of a very specific cream (methyl amino levulinic acid – Metvix) which is then activated by light. Specifically a red light (Actilite) but more
recently natural sunlight can be used.
When applied to your skin, the Metvix cream is selectively taken up into the sun damaged and skin cancer cells. It is then converted in to a natural chemical in the cell, which is very sensitive to light. When the correct form of light is applied to the skin the chemical then selectively destroys the abnormal cells. The healthy cells are spared making this treatment very safe but very effective.
We use a combination of approaches allowing us to tailor the treatment to suit you best.
We offer three types of PDT:
- Conventional PDT
- Daylight PDT
- Laser enhanced PDT
Is PDT safe?
Metvix cream is highly selective for cancerous and precancerous cells. This means that it has an excellent safety profile. The risk of scarring or pigmentation changes in the skin are extremely low as healthy tissue and cells are not affected.
It is not used if you are pregnant or breast feeding.
What are the benefits of PDT?
The key benefits of PDT are:
- It is highly effective
- It is very safe
- Minimal downtime
- Ability to treat large areas at a time (Field treatment)
- Excellent cosmetic results
- Improvement in the signs of skin aging
- Removal of precancerous skin lesions to reduce the risk of future skin cancer development.
What is the treatment procedure for photodynamic therapy?
At Complete Skin Specialists we have a number of modified versions of this treatment to maximize your results.
We will choose a treatment protocol which will take into account
- what we are trying to treat (skin cancer vs sun damage)
- The size of the area to be treated
- Location (face hands chest)
- Number of skin problems (pigmentation, capillaries etc)
With photodynamic therapy, one or more lesions can be treated at the same time. In most cases, the treatment protocol consists of 3 steps:
- Lesion preparation: to better assist absorption of the active chemical, the surface of the lesion is gently scraped to remove dead skin, crust or similar.
- Cream application: The photoactive cream is applied to the lesion and surrounding skin.
- Light source exposure: Red light PDT, Daylight PDT and Laser Enhanced PDT
Red light PDT
This is generally used for smaller areas and skin cancers.
The Metvix cream is applied under a dressing. This needs to be left on for 3 hours to allow the cream to absorb properly. During this time you are free to go home or leave our rooms and return.
After the 3 hrs we remove the dressing and shine the red light over the treatment area for 7 minutes. Local anaesthetic injections are sometimes used prior to the red light to help with discomfort.
For skin cancers, a second cycle of treatment is routinely repeated 2-4 weeks later.
This is a newer application for PDT, specifically for the treatment of extensive sundamage (field therapy). It can be used for large areas such as the face, scalp,
You will be supplied with some creams to use in the 2 weeks leading up to treatment to prepare the skin.
Your skin will be prepared with a cleansing regime that allows for better penetration of the medication.
A sunscreen of SPF 30 will be applied to the face followed by Metvix which will then be applied to the area being treated and left in place for 30 minutes.
You then sit outside in the daylight for 2 hours.
The cream is then washed off and sunscreen applied. Sun protection is very important for the next 48 hours.
Treatment is effective in both sunny weather and cloudy weather, all we require is daylight. It cannot be done on a rainy day.
The red and blue wavelengths in daylight activates the chemical just like the red light does – but the activation is much more gentle over a longer period of time and is virtually pain free.
The end reaction is like a moderate sunburn – peaking in severity 2-4 days after treatment, usually by the end of one week most of the peeling is complete.
Clearance of 70-80% of sunspots can be expected. This treatment is an excellent option for patients who do not want to use other topical agents including liquid nitrogen cryotherapy, and other topical treatments that are currently available.
Laser Enhanced PDT
We are able to improve your results by combining PDT with either our fractional CO2 laser or V beam (pulsed dye) laser.
The CO2 laser is used to create tiny channels in skin which is thicker such as the back or the hand or scalp. This improves the penetration of the Metvix cream to enhance it’s effectiveness.
We can also combine it with our V bam laser to treat capillaries and redness in one session to give you a better overall cosmetic result.
What can I expect after the treatment?
Following PDT, the treated areas will appear quite red with peeling for up to one week. Temporary swelling around the lips and eyes can occur for a few days. You may also notice that any brown spots temporarily darken, and then peel off leaving normal skin behind (this may take up to 10 days to occur).
This is considered a normal and desirable reaction to achieve clearance of these lesions.
Longer term how much improvement can I expect?
Improvement in the skin can continue for up to 3 months following treatment.
The results are variable, and depend on the degree of damage your skin has endured over the years. However, most patients are happy with the results after just one treatment.
Expected improvements include
- Significant clearance (70-80%) of actinic keratoses (rough dry red scaly skin patches)
- Improved smoothness of the skin
- Improvement in mottled brown pigmentation
- Fine wrinkles and some redness
PDT does not improve
- Coarse/deep wrinkles
- Capillaries (telangiectasia)
- Enlarged oil glands
- Seborrhoeic keratoses (warty lesions)
Will I need more than one treatment?
Typically you will only require one or two treatment sessions. However, depending on the degree of your sun damage may suggest that you have the treatment done on a every one to two years. No one treatment can clear sun damage completely and permanently. Unfortunately we also accumulate more over time requiring maintenance.