Only seven years after the construction of the first laser by Maiman in 1960, the dermatologist Professor Leon Goldman/USA reported about the first therapeutic laser application in patients with vascular lesions and tattoos in his book Biomedical Aspects of the Laser. In the seventies and early eighties, mainly the argon and carbon dioxide laser were used because of their thermal destructive effects. Most important indications were port-wine stains, telyangiectasias, and the removal of tattoos. A mile stone in laser therapy was the principle of selective photo thermolysis published by Anderson and Parish in Science in 1983. The use of a wave length with high absorption in the target structure and a very short exposure time shorter than thermal relaxation time of the target structure and a sufficiently high energy density allowed the destruction of the target within the skin without damage to the surrounding tissue. Target structures were, for example, ectatic vessels of port-wine stains, tattoo pigment, or melanin-pigmented cells. Nowadays, lasers are an indispensable therapeutic tool in dermatology. They can be used for the treatment of vascular lesions such as port-wine stains, childhood hemangiomas and telyangiectasias, epidermal and organoid nevi, melanin pigmented lesions, tattoos, or benign tumors, inflammatory lesions, virus papillomas, sun-damaged skin, wrinkles, and for epilation. Analogous to the many indications for laser therapy, the number of applied lasers is also very high. Lasers used for selective photo thermolysis are pigmented lesion dye lasers (PLDL,510 nm), flash-lamp pumped pulsed dye lasers (FPDL, 585 nm), long-pulsed tuneable dye lasers (LPDL, 585–600 nm), Q-switched ruby lasers (694 nm), Q-switched Nd:YAG lasers (1064 nm), frequency doubled Q-switched Nd:YAG lasers (532 nm), Alexandrite lasers (755 nm), and diode lasers (800 nm). Apart from these laser units, argon lasers (488 and 514 nm), copper vapour lasers (515 and 578 nm), Krypton lasers (589 nm), and frequency doubled Nd:YAG lasers (532 nm) are also routinely used. Cw-Nd:YAG lasers (1064 nm) are mainly applied if unspecific coagulation of the tissue is warranted. Lasers for vaporisation and ablation include cw-CO2 lasers, pulsed CO2 lasers, CO2 lasers with scanner, and Erbium:YAG lasers. Since not every indication and laser can be covered in one single issue of the journal, topics and authors were selected according to areas of interest. This issue includes articles on ablative therapy with the Erbium:YAG laser, treatment of vascular lesions, analysis of different cooling devices, a study on laser epilation, and the therapy of neurofibromatosis. Two non-dermatological papers on “Indocyanine Green Therapy for Hypopigmented Choroidal Melanoma” and on “Optical Tomography for the Imaging of Rheumatoid Arthritis” describe techniques which are also important in dermatology. In summary, I believe that this issue of Medical Laser Application will be of interest to readers since the articles emphasise laser therapy with regard to the scientific point of view instead of more commercially orientated cosmetic aspects. This issue will help to define the important role of lasers in dermatotherapy.
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