Comparison of Picosecond and Q-switched Laser for Benign Pigmented Lesions Treatment

The Comparison of Picosecond 532 and 1,064 Nanometers Laser and Q-switched Nd:YAG 532 and 1,064 Nanometers Laser in the Treatment of Benign Pigmented Lesions: A Randomized Controlled Trial

The objective of this study is to evaluate the efficacy and safety of picosecond 532 and 1,064 nanometers laser in the treatment of benign pigmented lesions compared with q-switched 532 and 1,064 nanometers laser.

Benign pigmented lesions can be divided into epidermal lesions such as freckles, lentigines, solar lentigines or cafe au lait macules and dermal lesions such as Nevus of Ota or Hori's nevus.

Q-switched 532 and 1064 nm lasers were reported to be safe and effective in the treatment of these benign pigmented lesions. By using selective photothermolysis theory, both q-switched 532 and 1064 nm lasers target on melanin causes photomechanical destruction of the melanin. However, the occurrence of post inflammatory hyperpigmentation (PIH) were reported especially in patients with darker skin type.

Recently, picosecond 532, 755, 1064 nm laser was reported to treat benign pigmented lesions effectively. With their ultra short pulse duration (picosecond domain), it is ideally believed to be pure photomechanical effects without thermal injury to surrounding tissue. As a result, the incident of PIH should be reduced.

The investigators then aimed to compared the efficacy and efficacy of different pulse duration between nanosecond and picosecond laser in the treatment of benign pigmented lesions.

Inclusion Criteria:

• age >18
• having any benign pigmented lesions on both sides of the face or any tattoo on any part of body which would like to be removed
• Fitzpatrick skin phototype 3-5

Exclusion Criteria:

• Previously treated with any laser within 3 months before enrollment into the study
• Patients with lesions with any clinical suspicion of being pre-cancerous or skin malignancies of any kind
• Patients who have photosensitive dermatoses
• Pregnancy and lactation woman
• Patients with wound infections (herpes, other) on the day of treatment
• Patients with moderate and severe inflammatory acne, Immunosuppressed patients, history of vitiligo
• Patients with unrealistic concerns/expectations and inability to do the appropriate post-operative care