ABSTRACT

The basic Reflectance Confocal Microscopy (RCM) optical section image is comparable to high-magnification histopathology at about 330; the advantage of RCM compared with histopathology is that optical sections can be obtained in vivo, with no disruption of the skin. Output images are horizontal and parallel to the surface of the skin, visually sectioned in a manner resembling histopathologic specimens in Mohs micrographic surgery. RCM examination of melasma lesions and the adjacent skin was performed, and RCM images were acquired at three levels: the suprabasal layer, dermoepidermal junction, and dermis. RCM features of melasma in the epidermis revealed a hyperrefractile cobblestone pattern in the basal cell layer and occasionally in the lower stratum spinosum, compared with the normal surrounding area. The presence of this cobblestone pattern was correlated histologically to increased melanin content in the keratinocytes. RCM examination has also been used for the evaluation of treatment response in melasma.