Background: Diode and long-pulse 1064 Nd:YAG lasers, because of their long wavelengths and extended pulse durations, have gained popularity over the last several years for photoepilation in individuals with dark skin phenotypes.
Objective: To analyze the clinical efficacy and histologic features of a new 810-nm diode laser in the treatment of unwanted hair in individuals with Fitzpatrick skin types II-IV.
Methods: Twenty-four female subjects (mean age, 33; range, 17-53) were treated three times at monthly intervals with the MeDioStarâ diode laser (Zeiss-Meditech, Jenna, Germany): wavelength 810 nm, spot size 12 mm, pulse duration 50 msec; fluence 25-35 J. Patients had skin types II-IV and light to dark brown hair. Hair counts were carried out using handheld magnifiers at baseline and at months 1, 2, 3, and 6. Six individuals had biopsies taken after treatment and at 3 and 6 months.
Results: A mean hair removal efficiency of 74% and 79% was noted at 3 and 6 months, respectively, and was best in those individuals with skin type III. Hair counts after treatment and at last follow-up were significantly lower when compared with the baseline counts (P<0.0001). Histologic analysis revealed a range from early catagen induction to complete follicular destruction.
Conclusions: This study supports the clinical photoepilatory efficiency of a new 810-nm diode laser in producing 70% clinical hair removal efficiency at 6 months. Histopathologic evaluation suggests that this decrease in hair counts is probably secondary to heat trauma to the follicular epithelium, resulting in complete follicular destruction and stopping of anagen phase.