Understanding Sun Damage

Australia has one of the highest rates of skin cancer in the world, and many of us accumulate years of sun exposure before we begin to notice its effects.

Sun damage occurs when ultraviolet (UV) radiation penetrates the skin and causes changes to skin cells, collagen, blood vessels, and DNA. While some effects are visible, others develop silently beneath the surface for years before becoming apparent.

Common signs of sun-damaged skin include:

Many people view sun damage as purely cosmetic, but it is also a marker of cumulative cellular injury and can increase the likelihood of developing skin cancer over time.

Actinic keratoses (AKs) are rough, scaly patches that develop on chronically sun-exposed areas such as the face, scalp, ears, chest, and hands.

These lesions are considered precancerous because they have the potential to progress into squamous cell carcinoma, a common form of skin cancer.

While some AKs are visible, many more may exist beneath the skin surface in what dermatologists call “field cancerisation”—areas of skin that have sustained widespread sun-induced DNA damage.

This is where Photodynamic Therapy (PDT) can be particularly effective.

Photodynamic Therapy (PDT) is a non-surgical treatment used to target sun-damaged skin and precancerous cells while minimising damage to healthy tissue.

The treatment involves three key steps:

A specialised cream is applied to the treatment area. This medication is preferentially absorbed by abnormal sun-damaged and precancerous cells.

The cream is left on the skin for a period of time, with an occlusive dressing that blocks any light from penetrating the cream. Allowing it to accumulate within damaged cells.

The area is then exposed to a specific wavelength of light.

When activated, the medication produces reactive oxygen molecules that selectively destroy abnormal cells while sparing much of the surrounding healthy tissue.

PDT offers several advantages:

For many patients, PDT serves as both a therapeutic and preventative treatment for chronically sun-damaged skin.

Following treatment, it is common to experience:

These effects are part of the treatment process as damaged cells are eliminated and the skin begins to regenerate.

Over time, patients often notice:

While PDT is highly effective at targeting abnormal sun-damaged cells, combining treatments can sometimes provide enhanced outcomes.

Fractional CO₂ laser resurfacing is one modality that may be used alongside PDT in selected patients.

CO₂ laser creates thousands of microscopic treatment channels within the skin. This stimulates wound healing, collagen remodelling, and skin renewal.

Benefits of fractional CO₂ laser treatment may include:

Research and clinical experience suggest that combining these treatments may provide complementary benefits.

The CO₂ laser can:

By targeting both abnormal cells and the structural damage caused by years of UV exposure, combination therapy can offer a more comprehensive approach to skin restoration.

Not every patient requires combination treatment, and suitability depends on individual skin type, sun damage severity, medical history, and treatment goals.

Even after successful treatment, ongoing sun protection is critical.

Key strategies include:

Sun damage is more than a cosmetic concern—it reflects cumulative injury to the skin that can contribute to premature ageing and increase the risk of skin cancer.

Photodynamic Therapy is an effective treatment for widespread sun damage and precancerous lesions, helping to target both visible and hidden cellular changes. In selected patients, combining PDT with fractional CO₂ laser resurfacing may further enhance skin rejuvenation and improve overall treatment outcomes.