Wavelength optimized cross-polarized wide-field imaging for noninvasive and rapid evaluation of dermal structures

Changes in the morphology of dermal collagen may indicate aging or pathological processes. At present, there is no technology for in vivo real-time assessment of collagen structures. Our goal was to introduce and validate polarization optical imaging for noninvasive quantitative evaluation of dermal collagen. Seventeen volunteers participated in the study. Cross-polarized 440 nm images were acquired noninvasively from facial skin of the study subjects. Collagen content and intensity histogram were computed from the optical images. Quantitative results showed a decrease in the collagen content with increasing age of the subjects. Analysis of the collagen image histogram parameters demonstrated decreasing mean pixel value and increasing full width at half maximum (FWHM) with increasing age. Polarization optical imaging has the potential for rapid noninvasive in vivo evaluation of human dermis. Cross-polarized imaging at different wavelengths emphasizes different features of human skin. (A) Skin photograph. (B) In vivo cross-polarized image at 440 nm. (C) In vivo cross-polarized image at 570 nm. (D) In vivo cross-polarized image at 690 nm.