Quantitative analysis of intrinsic skin aging in dermal papillae by in vivo harmonic generation microscopy.
Chronological skin aging is associated with flattening of the dermal-epidermal junction (DEJ), but to date no quantitative analysis focusing on the aging changes in the dermal papillae (DP) has been performed. The aim of the study is to determine the architectural changes and the collagen density related to chronological aging in the dermal papilla zone (DPZ) by in vivo harmonic generation microscopy (HGM) with a sub-femtoliter spatial resolution. We recruited 48 Asian subjects and obtained in vivo images on the sun-protected volar forearm. Six parameters were defined to quantify 3D morphological changes of the DPZ, which we analyzed both manually and computationally to study their correlation with age. The depth of DPZ, the average height of isolated DP, and the 3D interdigitation index decreased with age, while DP number density, DP volume, and the collagen density in DP remained constant over time. In vivo high-resolution HGM technology has uncovered chronological aging-related variations in DP, and sheds light on real-time quantitative skin fragility assessment and disease diagnostics based on collagen density and morphology.
Department of Dermatology, National Taiwan University Hospital and College of Medicine, National Taiwan University, Taipei 10002, Taiwan ; Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan ; yihualiao@ntu.edu.tw.
Yi-Hua
YH
Liao
Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan.
Wei-Cheng
WC
Kuo
Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan ; Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan.
Sin-Yo
SY
Chou
Department of Electrical Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
Cheng-Shiun
CS
Tsai
Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan ; Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei 10617, Taiwan.
Guan-Liang
GL
Lin
Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan.
Ming-Rung
MR
Tsai
Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan.
Yuan-Ta
YT
Shih
Department of Electrical Engineering, National Cheng Kung University, Tainan 70101, Taiwan.
Gwo-Giun
GG
Lee
Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan ; Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan ; Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taipei 10617, Taiwan ; Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei 10617, Taiwan ; Research Center for Applied Sciences and Institute of Physics, Academia Sinica, Taipei 11529, Taiwan.
Chi-Kuang
CK
Sun
(100.2000) Digital image processing; (170.0170) Medical optics and biotechnology; (170.1610) Clinical applications