Advances in optical coherence tomography imaging for dermatology.

Optical coherence tomography (OCT) is a non-invasive imaging technique, which has previously demonstrated potential for use in dermatology. The purpose of this study is to demonstrate how improvements in image quality, speed, and functionality enable qualitative and quantitative information to be obtained from in vivo human skin. We developed a portable fiber-optic based OCT imaging device that requires only 1 second to simultaneously provide high-resolution images of skin structure, collagen birefringence, and blood flow. Images of normal human skin were acquired in vivo, and features compared with clinical and histologic observations. The layered structure and appendages of skin were apparent in conventional OCT images, and correlated well with corresponding histology. Polarization-sensitive OCT images simultaneously revealed birefringent regions within the dermis corresponding to the location of collagen fibers, as confirmed with polarized light microscopy. Properties of collagen-rich tissues including tendon and scar tissues were quantified. Location of blood flow was also displayed alongside structural and polarization-sensitive images. Significant improvements in OCT technology have been made since its early application in dermatology. In particular, combining the previously described structural and Doppler imaging functions with polarization-sensitive imaging increases the utility of the technique for rapid, non-invasive investigations in the skin.