Q-switched ruby laser in cosmetic dermatology

The q-switched ruby laser has shown promising results in the treatment of blue and black tattoos. The red light of the ruby laser, 694 nm wavelenght, selectively absorbed by dark pigments, is converted into heat and pigments are immediately vapourized. Energy levels range between 4,5 and 12 J/cm(2). Short exposure time (nanoseconds) does not exceed the thermal relaxation time of the target structures. Thus, thermal damage of the surrounding tissue is minimal (selective photothermolysis). Not only exogenous pigment as tattoo ink but also physiological pigmented structures as melanocytes, melanosome loaden keratinocytes, and melanophages are affected by this type of laser application. Therefore the ruby laser represents a new option in the treatment of a variety of benign pigmented lesions in cosmetic Dermatology (e.g. actinic lentigo, simple lentigo, ephelides, melasma, speckled nevus, news of Ota, and Becker's news). The benefit of this source can be seen in efficient clearing of the lesions without scarring. As a side effect transient hypopigmentation may occur. Ruby laser treatment of melanocytic lesions cannot be recommended because unpigmented news cells do not absorb red light and persist unaltered. They still bear the potency of further transformation, as into malignancy.