From the Guidelines
Low-level laser (light) therapy for skin treatment is most effectively achieved with a wavelength of 630 nm, using a light source such as an argon dye laser, copper vapour dye laser, or semiconductor diode laser, with a fluence rate of 10-500 mW cm2, as recommended by the British Photodermatology Group 1.
Key Considerations
- The choice of light source should be based on the proposed clinical indications, including the number and size of lesions, priorities for a portable compact source, flexibility, treatment times, and cost.
- Fluence rates greater than 50 mW cm2 may begin to affect oxygen availability, and rates over 400 mW cm2 may induce hyperthermic injury.
- The total effective fluence, taking into account incident spectral irradiance, optical transmission through tissue, and absorption by photosensitizer, is a concept proposed for more accurate dosimetry.
Effective Light Sources
- Several light sources are effective in promoting the non-melanoma skin cancer (NMSC) applications of ALA-PDT, including:
- Argon dye laser
- Copper vapour dye laser
- Semiconductor diode laser
- LED array
- Xenon arc
- Metal halide
- Tungsten/halogen
Treatment Parameters
- The administered ALA dose and vehicle
- The drug-illumination interval
- The wavelength/band, fluence rate or irradiance (mW cm2), and fluence or dose (J cm2) of externally delivered light
Clinical Applications
- Topical ALA-PDT is effective in the treatment of certain non-melanoma skin cancers, including actinic keratoses, Bowen's disease, and superficial basal cell carcinomas.
- PDT may prove advantageous where size, site, or number of lesions limits the efficacy and/or acceptability of conventional therapies.
- Experience with the modality in other skin diseases remains limited, but areas where there is potential benefit include viral warts, acne, psoriasis, and cutaneous T-cell lymphoma, as reported by the British Photodermatology Group 1.
From the Research
Low-Level Laser (Light) Therapy for Skin Treatment
Low-level laser (light) therapy (LLLT) is a technology used to treat various skin conditions, including:
- Wrinkles
- Acne scars
- Hypertrophic scars
- Burns
- Pigmentary disorders such as vitiligo
- Inflammatory diseases like psoriasis and acne 2 LLLT has been shown to stimulate healing, relieve pain and inflammation, and restore function by absorbing red and near-infrared wavelengths, which are then absorbed by mitochondrial chromophores in skin cells 2.
Mechanism of Action
The mechanism of action of LLLT involves the absorption of photons by mitochondrial chromophores, leading to:
- Increased electron transport
- Adenosine triphosphate (ATP) production
- Nitric oxide release
- Increased blood flow
- Reactive oxygen species increase
- Activation of diverse signaling pathways 2 This can lead to the activation of stem cells, allowing for increased tissue repair and healing 2.
Clinical Applications
LLLT has been used to treat various skin conditions, including:
- Skin rejuvenation
- Acne vulgaris
- Wound healing
- Body contouring
- Androgenic alopecia 3 Studies have shown that LLLT can be a safe and effective method for skin rejuvenation, treatment of acne vulgaris and alopecia, and body contouring 3, 4.
Safety and Efficacy
LLLT has been shown to be a safe and effective treatment modality for sensitive skin, with no adverse effects reported in several studies 4, 5. The treatment has also been shown to improve skin elasticity, reduce wrinkles, and increase patient satisfaction scores 4. However, more research is needed to fully understand the mechanisms of action and to establish the optimal treatment parameters for different skin conditions 3.