Analysis of the therapeutic effects on skin rejuvenation for the different treatment conditions of 1064nm Nd: YAG Laser: Simulation and phantom study

Abstract

In this study, we analyzed internal and external skin temperatures as well as penetration depths for the different treatment conditions regarding the 1064 nm Nd:YAG laser to find the optimum treatment condition for skin rejuvenation. We transmitted the laser into a skin mimicking phantom with laser fluence conditions of 26, 30 and 36 J/cm2, and spot diameter conditions of 8 and 10 mm. We also selected the pulse duration as 30 ms, and measured internal-external skin temperatures and penetration depths. To examine the distribution of internal-external skin temperatures, we performed a heat transfer analysis based on the finite element method. Skin layers were designed as three-dimensional models to predict skin temperatures more accurately. We employed the same laser conditions of fluence and spot diameter while performing actual and simulation analyses. Consequently, we found that laser conditions for a spot diameter of 8 mm with a fluence of 36 J/cm2 and a spot diameter of 10 mm with a fluence of 26 and 30 J/cm2 demonstrate the greatest effectiveness toward skin rejuvenation. Moreover, the penetration depths and the range of thermal distribution increased as the fluence and spot diameter increased. In particular, the spot diameter influenced the therapeutic effects more seriously than the fluence. © 2014 National Taiwan University.