The goal of this study is to establish the safety of high fluence LED-RL from 160 J/cm2 up to 640 J/cm2 in healthy subjects. The hypothesis is that high fluence LED-RL phototherapy is safe in human skin.

Skin fibrosis is involved in a variety of pathologic processes ranging from exuberant scar formation secondary to surgery or trauma, as in hypertrophic and keloid scars, to immune-mediated processes such as scleroderma and chronic graft-versus-host disease. As highlighted by quality-of-life studies, skin fibrosis imparts a significant socioeconomic burden due to the functional, aesthetic, and psychosocial impact it has on a patient's life. The effects of visible light, while common in the environment (visible spectrum accounts for 44% of total solar energy), remain undefined. An important safety feature of visible red light (600 nm to 700 nm) is that it does not generate pro-carcinogenic DNA damage as does ultraviolet (UV) light. Recently published clinical observations indicate that red light in combination with other modalities such as photosensitizers in combined red light photodynamic therapy can lessen skin fibrosis. However, preliminary in vitro data generated by the investigator's research group suggests that red light can function as a stand-alone treatment, eliminating the side-effects of chemical photosensitizers and the potential long-term harm of current UV therapy. Furthermore, commercially available light emitting diode-red light (LED-RL) units exist and are already FDA-cleared for other dermatological uses (such as rhytides and acne), thus clinical translation for use in skin fibrosis could occur relatively quickly following safety and efficacy demonstration. Developing high fluence LED-RL phototherapy as a treatment for skin fibrosis would represent an important advance in scarring conditions that lacks the serious systemic side effects associated with immunomodulatory agents (such as oral steroids); avoids the need for invasive, painful injections with anti-fibrotic agents (such as intralesional steroids, 5-fluorouracil and bleomycin); and eliminates the UV-induced DNA damage associated with skin cancer and photoaging that are associated with current UVA/UVA1 and UVB/narrowband UVB phototherapy. To the investigator research group's knowledge, no clinical trials have been performed to determine the safety of high fluence LED-RL for treatment of skin fibrosis. Therefore, the innovation of this approach is that the investigator research group intend to study high fluence LED-RL as a safe modality for treatment of skin fibrosis.

Inclusion Criteria:

• Healthy subjects of any sex, ethnicity and age
• Nondominant proximal anterior forearm is wide enough to ensure reproducible placement of LED-RL phototherapy or mock therapy hand-held unit
• Available and willing to attend all clinic visits
• Able and willing to give informed consent

Exclusion Criteria:

• Subjects using any photosensitizers (i.e. lithium, melatonin, phenothiazine antipsychotics, antibiotics)
• Subjects with diabetes mellitus (DM)
• Subjects with a history of skin cancer; basal cell carcinoma (BCC) or squamous cell carcinoma (SCC).
• Subjects with systemic lupus erythematous (SLE)
• Subjects with any other medical condition that could be compromised by exposure to the proposed treatment
• Subjects with light-sensitive conditions or on photosensitizing medications (All subjects will be tested for photosensitivity per manufacturer user guide instructions)
• Subjects with open wounds on the nondominant proximal anterior forearm
• Subjects with fibrotic skin disease or other skin conditions on the nondominant proximal anterior forearm
• Subjects with tattoos that cover the procedure site on the nondominant proximal anterior forearm