DigiSkinDia

Background: 

According to WorldLifeExpectancy 2017 almost 95 thousand people worldwide will die annually from skin cancer; most of them be-cause of melanoma malignant. The malignant melanoma is a skin cancer that develops from melanocytes, which are the pigment-containing cells. The melanoma grows fast and easily metastasis. It is highly lethal in a case of not early diagnosed. Early diagnosis allows a cure rate of up to 90% thus accurate diagnosis methods are needed. Due to the rapid course of the disease time factor in discovering the malignant melanoma is crucial.

Considering a typical expanse of the skin cells in the basal layer of about 10 microns, resolu-tions of 1 micron or less are required for the representation of subcellular details. If these resolutions are given, an early diagnosis at the cellular level or a course assessment in a physiological environment is possible. Optically high-resolution non-invasive imaging meth-ods on a morphological-functional basis, such as in vivo multiphoton tomography (MPT), are suitable for this purpose. Subcellular morphological details of the tissue can be displayed without exogenous marker substances (label-free) based on molecules itself. In particular, the mechanisms of two-photon excited autofluorescence (2P-AF) and second harmonic gen-eration (SHG) are used. Additionally, the complementary detection of the fluorescence in a time-resolved fashion provides access to fluorescence lifetime imaging (FLIM) a further con-trast method with chemical selectivity. This combination of chemical-selective imaging and subcellular spatial resolution allows insight into the metabolism of cells and thus access to functional imaging. Based on these methods a significant clinical application is established, namely highresolution noninvasive and nondestructive imaging of living tissue – well known as nonlinear "optical biopsy".