Tattoo Removal in Micropigs with Low-energy Pulses from a Q-switched Nd:YAG Laser at 1064nm

摘要

Treatment of pigmental lesions in skin with visible or near-infrared nanosecond (ns) laser pulses often causes significant collateral tissue damage because the current approach uses pulses with energy of 300mJ or larger. Additionally, this requires large Q-switched laser systrems. To overcome these disadvantages, we have investigated a different approach in delivering ns laser pulses for cutaneous lesion treatment. Tattoo removal in an animal model with a focused laser beam from a Q-switched Nd:YAG laser has been investigated in two Yucatan micropigs tattooed with blue, black, green and red pigments. The tattoos were treated with a focused beam of 12ns pulses at 1064nm, with different depth under the skin surface, while the micropig was translated to achieve an effect of single pulse per ablation site in the skin. With the pulse energy reduced to a range from 38 to 63mJ, we found that nearly complete clearnance was achieved for blue and black tattoos while clearnance of red and green tattoos was incomplete. Analysis of the skin appearance suggested that the pulse energy can be decreased to below 20mJ which may lead to further reduction of the collateral tissue damage and improve the clearance of red and green tattoos.