Photodynamic Therapy (PDT) With Levulan Kerastick for Acne, Rejuvenation and Actinic Keratoses
Photodynamic therapy (PDT) is a two-step procedure involving the use of a photosensitizing agent plus a light source to treat various skin conditions, including skin cancer and actinic keratoses, acne, and photoaging. In step one, a photosensitizer (Levulan Kerastick) is applied to the skin, where it is taken up by the target cells. In step two, the photosensitizer is activated with a specific wavelength of light. The uptake of Levulan by only certain cells and the focusing of light only on the area to be treated imparts selectivity to the procedure.
Photodynamic therapy for acne
Levulan accumulates in sebaceous glands and the epidermis, as well as in P. acnes bacteria, allowing PDT to target acne. The use of PDT for acne is off-label but widely used by dermatologists. After incubating on the skin for 30-60 minutes, the Levulan is activated with a light source. At SOMA Skin & Laser we use the Vbeam pulsed Dye Laser. The resulting decrease in sebaceous gland activity and P. acnes bacteria can lead to significant acne improvement.
Photodynamic therapy for photoaging
The exact mechanism of photodynamic therapy for rejuvenation is not certain, but stimulation of collagen deposition is thought to be important. Photodynamic therapy for the treatment of photoaging is one of the most sought after and popular cosmetic procedures.
Photodynamic therapy for skin cancer and precancers
Cancer cells accumulate more Levulan than normal cells, allowing photodynamic therapy for the treatment of actinic keratoses, Bowen's disease, and basal cell carcinoma. Treatment of actinic keratoses is the only FDA-approved indication for Levulan. In most patients, a brisk phototoxic reaction occurs with erythema, edema, crusting, and erosion. This is considered necessary to clear these lesions.
How does PDT work?
Following light activation, porphyrins are excited to a higher energy state, which can result in generation of reactive oxygen species, such as singlet oxygen or free radicals. Porphyrins from Levulan are concentrated near mitochondria, leading to cell death of malignant or pre-malignant cells upon light exposure. For the treatment of acne, preferential accumulation of Levulan in sebaceous glands as well as reduction in Propionibacterium acnes, the bacteria implicated in acne, is thought to be the responsible mechanisms. For treatment of photoaging, increased collagen synthesis following photodynamic therapy may play a role.
Is photodynamic therapy covered by insurance?
The use of phototodynamic therapy for the treatment of skin cancers and pre-cancers is often covered by insurance. Photodynamic therapy for acne or rejuvenation is not reimbursed by insurance.
How much does photodynamic therapy cost?
For acne or rejuvenation, photodynamic therapy, including use of the Vbeam Pulsed Dye Laser, costs $550 per treatment.
During and after photodynamic therapy
During photodynamic therapy you may feel a burning or stinging sensation. We often use a fan or gentle misting of liquid nitrogen during the procedure. After the PDT procedure, you must entirely avoid the sun for several days, as severe reactions are possible since there is still photosensitizer on the skin. Erythema (redness) and edema (swelling) often occur, followed by peeling. There can be a burning sensation, pain, crusting, and blister formation. Hyperpigmentation is sometimes seen after PDT, usually resolving over several months. Hypopigmentation has also been reported.