Laser skin resurfacing using a frequency-doubled Nd:YAG laser after application of a chromofilm
This study aimed to evaluate a new skin laser resurfacing technique using a 532 nm laser after previous application of a chromophore on the skin. For this study, a film (Chromofilm), based on transfer process was developed. This 4 layers film allows the control of all parameters (thickness, chromophore concentration, chromophore distribution) before its application on skin surface. The new laser skin resurfacing technique was evaluated on human skin before a surgical face lift procedure. The film was applied on photodamaged skin located in periauricular areas. On both sides four areas were treated. The laser irradiation was performed 15 h prior to undergoing face lift (4 areas), and 1 h before (4 areas). The laser irradiation was performed with a 532 nm Nd:YAG laser (Ophtalas FX2, Alcon Biophysic) connected to a scanner (HexascanR, Prein & Partners) with the following parameters: power 2 W, spot diameter 1 mm, hexagonal surface irradiation 7 mm and pulse duration ranging from 50 and 120 ms. Tissue samples were examined histologically to determine the depth injury using nitroblue- tetrazolium chloride (NBTC) staining, haematoxylin-eosin staining, Weigert's staining and Masson's staining. The results showed that the depth of injury was clearly dose- dependent. 50 ms pulse duration induced total epidermis ablation and fine dermal coagulation. 120 ms pulse duration induced dermal coagulation down to 120 micrometers. No residual of carbon film were observed on histologic sections. In conclusion, laser skin resurfacing using a 532 nm laser irradiation after application of carbon film transfer is an effective method for skin resurfacing.
This paper was published in SPIE Proceedings Vol. 3564