285 various pigmented skin lesions from 282 patients, using the square and uniform intensity ruby laser equipment for the past two years and ten months, have been treated. Laser effects on 44 skin specimens, which were excised through conventional operations, have also been studied histologically. The effect of laser therapy was graded as excellent (around 90% improvement), good (around 70% improvement), fair (around 50% improvement) and poor (under 30% improvement).
The effective rate of 6-month or more follow-up cases was 12/96 (12.5%) in pigmented nevus, 13/75 (17.3%) in nevus spilus, 3/5 (60.0%) in Becker's nevus, 3/7 (42.9%) in epidermal nevus, 9/17 (52.9%) in senile freckle and 9/12 (75.0%) in seborrheic keratosis, respectively.
As for a pigmented nevus, effective results may be rather expected when no or very few junctional nevus cell nests are in the lower epidermis, and when nevus cells are sparse and relatively limited in the upper dermis. As for a nevus spilus, tardy type seems to respond to the ruby laser treatment more satisfactorily than congenital type. Anyway, preliminary test irradiation is recommended and evaluated before further treatment of the whole lesion in both extensive pigmented nevus and nevus spilus.
Moderate to high effective rate may also be expected for epidermal nevus, senile freckle and seborrheic keratosis because of reliable epithelial peeling effect of ruby laser beam. Some discussion was also performed how to improve the effectiveness of ruby laser treatment.
