In-vivo diagnostic with optical coherence tomography: Use in dermatology

Optical low coherence tomography (OCT) is a newly developed bioengineering method for noninvasive in-vivo investigation of human skin, especially of the epidermis. Based on the principle of a Michelson interferometer, OCT allows the detection of the path length of an infrared light beam after backscattered inside the skin sample by comparison with a reference beam. The depth resolution is limited by the coherence length of the light source, which is about 15 micrometer. OCT supplies cross-sectional images of the skin with a penetration depth of about 0.5 to 1.5 mm. The stratum corneum can be distinguished from the living epidermis and the upper dermis. We investigated healthy skin of several localizations, inflammatory diseases, intra- and subepidermal blisters and epidermal tumors. First images are presented to demonstrate the possibilities of this promising new method.