CUTANEOUS EFFECTS OF PULSED NITROGEN GAS-LASER IRRADIATION

[摘要] The effects of pulsed N gas laser emission (337.1 nm wavelength) were studied on human skin. The laser provides high-intensity monochromatic UVA [long-wave UV] radiation and can elicit delayed erythema in an actual exposure time of about 1 ms (105,000 pulses, each lasting 10 ns, delivered over 210 s). The effects of N laser irradiation were compared clinically and histologically with conventional erythemogenic UVA and UVB [shorter-wave UV] exposures from Xe arc or Hg arc lamps and were similar in many respects. The minimal erythema dose is comparable to that obtained using more conventional continuous light sources which have more than 100 times lower intensity. A phototoxicity comparison of oral and topically applied psoralens is presented, indicating that the laser may prove useful in comparing photosensitizing capacity of certain compounds.