Laserwelt.com

L - ight A - mplification by S - timulated E - mission of R - adiation LASER – light is monochromatic (only 1 wavelength), coherent (in time and space), parallel and can easily be focussed. Most often, lasers cause a thermal destruction of the target structure or the target chromophore (coagulation, carbonisation, vaporisation). With suitable wavelengths and short pulses the principle of selective photothermolysis is applied. This means that haemoglobin is the target chromophore for treating vascular lesions, melanin is the target chromophore for treating pigment lesions and coloured pigments are the target chromophores when removing tattoos. At the same time, maximum safety for the surrounding tissue should be guaranteed. When using lasers, the restricted penetration depth can often cause problems. Deeper vascular lesions can either be treated interstitially with the long-pulsed Nd:Yag laser using fibre or transcutaneously with the Nd:Yag laser using a prism. The CO² laser which is mostly absorbed in water is used for ablation of large-scale tissues (e.g. virus warts) and for cutting (“light scalpel” without leaving bloody wounds). The Er:Yag laser is used for very smooth ablation of superficial cell layers (“skin resurfacing”) with low shrinking effect. See Laser protection course!