The evaluation of the photoaging of the human skin by three-dimensional polarization sensitive spectral domain optical coherence tomography

Noninvasive evaluation of dermal degeneration is important for a diagnosis of photoaging. Polarization sensitive optical coherence tomography (PS-OCT) can measure the distribution of phase retardation caused by birefringence property of collagen. The PS-OCT has been reported as the technology of in vivo investigation of collagen structure in the skin. PS-spectral domain (SD)-OCT provides a three-dimensional phase retardation volume, and it provides an en face distribution map of the slopes of cumulative phase retardation. In this research, we measured the lateral orbital area and forehead of 7 young (age = 24.7±1.1) and 6 elder (age = 72.5±1.4) volunteers by a custom-built 840 nm fiber based PS-SD-OCT. This system can measure the skin birefringence three-dimensionally (5.5 sec for a 3-D volume). There was a significant difference in mean of the distribution of phase retardation slopes of the lateral orbital area between young and old cohorts (young: 0.356±0.0255 degree/μm; elder: 0.256±0.0118 degree/μm). However, there was no significant difference in forehead. On the other hand, the shapes of histogram was not normal distribution. Therefore, we calculated skewness and kurtosis of the distributions of slopes for the analysis. In the orbital area, there were also significant differences between young and old cohorts in skewness (y: 0.813±0.135; e: 1.51+/- 0.177) and kurtosis (y: 2.85±0.483; e: 5.23±0.862). In forehead, there was a significant difference between young and old cohorts in skewness (p=0.0289) in contrast with mean (p= 0.065).© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.