Abstract
A ruby laser has been clinically used for patients with pigmented cutaneous lesions to reject selectively over-deposited melanin granules (MG) in the skin. Previously using a medical ruby laser system with wave length 694 nm and pulse duration of 2 msec (Toshiba LRT-301A), we obtained excellent results in treatment on cases of nevus spitus, senile lentigo and seborrheic keratosis in which MG are present in the epidermis and dermis. On the other hand, we could not get adequate effects with this type of laser system on nevus pigmentosus and/or nevus Ota which include MG in the deep dermis. In the present study, we have applied modified Toshiba LRT-301A ruby laser system with shorter pulse duration of 200-400 microsec. on with various pigmented dermatoses. In cases of superficial pigmented diseases, such as nevus spilus, senile lentigo and seborrheic keratosis, the therapeutic effects obtained were similar to those of with ordinary type. In cases of both nevus pigmentosus and nevus Ota, however, more favorable effects could be obtained using the short pulse ruby laser system.
