The diode laser emits laser energy in the 800 nm wavelength range and the absorption of the laser light by melanin is similar to the alexandrite laser [56]. A recent study has reported the use of the diode laser to treat persons with skin types V and VI skin types using two
treatment regimens [95]. The first treatment consisted of fluences ranging from 15 to 25 J/ cm2 and a pulse width of 30 ms. Mild crusting and hyperpigmentation were noted with these treatment parameters. Histological studies showed mild epidermal damage and occasional subepidermal separation at the dermal epidermal junction. Full thickness epidermal damage and thermal damage in the dermis were found in samples from subjects receiving higher levels of these fluences. The second laser had a pulse width of 100 ms and a fluence of between 20-30 J/cm2 [96]. The overall histological evaluations were similar with the longer pulse width with less epidermal damage when similar fluences were compared. Greppi treated eight subjects with skin types V-VI for pseudofolliculites barbe with 10 J/cm2 with a pulse width of 30 ms [97]. Treatments were given 4-6 weeks apart, and subjects received 7-10 treatments. Hypopigmentation was found in two subjects, and hyperpigmentation in three patients. Both types of pigment changes were resolved within eight months (Table 8.3).