When a part of the skin has an abnormal growth or appearance compared to the skin around it, it is considered a skin lesion. There are two types of lesions: primary skin lesions, or abnormal skin conditions someone is either born with or acquires over their lifetime, and secondary skin lesions that result from irritated or manipulated primary skin lesions (e.g., from scratching a mole until it bleeds).
LLLT is effective for wound healing in nonhealing defects as well as for a number of skin conditions that cause lesions. For example, several studies have found that LLLT works well as an acne treatment and shows a significant reduction in active acne lesions after 12 sessions of treatment. Additionally, a combination of blue light and red light has been shown to create a special synergy with strong anti-bacterial and anti-inflammatory effects on skin lesions.