[Histological changes elicited by hair removal lasers].

Several different laser systems are currently used to remove unwanted hairs. In this study, we studied follicular changes following hair removal with ruby or alexandrite lasers at different fluences. Unwanted hairs were treated with a ruby laser (ICN, Photon Ics, UK) at 10, 14, 18 J/cm(2) or an alexandrite laser (Cynosure, USA) at 11, 14, 17 J/cm(2). A 3 mm punch biopsy was taken immediately after each laser exposure and one month later. Specimens were stained for histological observations. They were observed using immunohistochemistry to Factor VIII related antigen and PCNA, and also by the TUNEL method. Immediately after the laser exposure, moderate follicular damage was observed following treatment with either laser. One month later, cystic formation of hair follicles and foreign body giant cells were observed in skin treated with either laser. The similar influence of each laser treatment resulted in similar histological changes. In this study, the histological changes following treatment with a ruby or an alexandrite laser at the same fluence were considered to be similar.