[Multiphoton tomography].

In recent years, multiphoton tomography (MPT) and multiphoton microscopy have gained increasing importance as noninvasive examination techniques in dermatology. MPT imaging is based on the specific stimulation of biogenic fluorophores. The induction of second harmonic generation is also used for imaging of particular molecules. Additional fluorescence staining or fluorescence markers are not necessary-an important advantage for the in vivo examination of human skin. Multiphoton techniques are not only appropriate for clinical diagnostics but also for biomedical research. MPT provides an optical biopsy depth up to 200 µm with subcellular resolution depicting cellular and extracellular structures. In combination with fluorescence lifetime imaging, additional information about the microenvironment, the energetic state and the cellular metabolism can be obtained. This review presents recent developments of MPT for the in vivo evaluation of physiological and pathological changes of skin and diagnostics of dermal diseases.