Evolution and principles of dermoscopy

Dermoscopy, also known as dermatoscopy or epiluminescence microscopy, is a non-invasive diagnostic technique that allows detailed visualization of skin structures invisible to the naked eye. The origin dates back to the Renaissance era; however, its clinical utility became evident in the 20 th century, particularly for differentiating benign and malignant tumors. Today, the advancements in dermoscopic technology, such as the integration of polarized and non-polarized techniques, have enhanced its diagnostic precision and management of various inflammatory dermatoses, pigmentary disorders, infectious conditions, and diseases of the hair, scalp, and nails. Superficial structures are better visualized with non-polarized dermoscopic technique which requires a liquid interface and direct contact between the dermoscope and the skin. Polarized dermoscopic technique, on the other hand, enables visualization of structures in the deeper layers of epidermis and papillary dermis and can be used in contact or non-contact mode, with or without a liquid interface. Modern developments like ultraviolet reflectance dermoscopy further aid in the management of various pigmentary disorders, superficial infections, and porphyrias.