The OCT can provide cellular resolution (~1m in lateral and axial directions) images. A cellular resolution OCT has the characteristics of non-invasive, non-radioactive, labelfree, real-time and high tissue penetration depth that are highly valuable for clinical use. This technology allows visualization of important structural features such as the epidermis and dermis and the epidermal-dermal junction. OCT has the advantage of generating cross-sectional images, like the orientation of pathology slides.

The ApolloVue S100 Image System is intended to be used as a non-invasive imaging tool in the evaluation of external human skin tissue microstructure by providing two-dimensional, crosssectional (B-scan) and en face (E-scan) real-time visualization for assessment by physicians to support in forming a clinical judgment. For the ApolloVue S100 Image System image, both cross-sectional view and en face view can be obtained to assist physicians' diagnosis. With both views, physicians can obtain important spatial information in regards to the skin. Besides, the ApolloVue S100 Image System is equipped with an image guiding system which provides a high-resolution dermatoscope like image, for the positioning of skin sites for optical biopsies.

In this protocol, it is proposed to study the optical imaging features of healthy human skin and nevi and the evaluation of usability. We propose to recruit 60 subjects for such a trial. Healthy volunteers will be approached and consented to this protocol. The volunteers will be imaged.