PubMed2001
The laser depilation system, cleared by the Food and Drug Administration since 1995, is evolving rapidly. However, the parameters in the hair removal function of these devices emphasize use for white people with fair skin (Fitzpatrick types I, II, or III). The characteristics of oriental skin and hair are black, coarse hairs in darker skin (Fitzpatrick types IV or V). As seen, the higher the skin melanin content, the more difficult to remove hair by laser. The authors report 146 oriental patients (156 body sites) who underwent treatment with the long-pulse alexandrite laser (wavelength, 755 nm) depilation system since November 1997. Percentage of hair removal (clearance rate) was assessed, and the histological change from laser pulse damage was observed. After two treatments, the clearance rates in the axillae and the leg were 61% and 62% respectively in the 15 to 20-J group (N = 47), and were 66% and 67% respectively in 21 to 25-J group (N = 64). After five treatments, 59 patients (37 axillae and 22 legs, all of which received 21-25 J per square centimeter of laser energy treatment during the course) had an average clearance rate of 91% (axillae) and 86% (leg), and the clearance rates have been maintained near 90% after long-term follow-up (average follow-up, 17 months). Minimal and transient complications are noted. In conclusion, using a combination of longer wavelength (but still in the optimal window of 630-870 nm), long pulse duration (10-40 msec), high fluence (but limited up to 25 J per square centimeter), multiple treatments, and concomitant direct cooling applied to the skin of oriental patients (Fitzpatrick types IV and V) with black, moderately coarse hair shafts achieves satisfying long-term hair removal results.