The most successful treatment of darker skin types has been reported when careful consideration of the epidermal tissue response to the treatment has been taken into account [3,4]. The use of test spots to select the best fluence and pulse duration for each individual has been reported to be helpful in reducing side effects. If test spots are used, it is recommended to choose a nonobvious location that matches the skin color, sun exposure, and hair density of the area to be treated [81]. Then use two to four fluences starting with a lower fluency setting and longer pulse duration, and gradually increasing the fluences and shortening the pulse durations. It may take up to 48 hours for the full cutaneous response to develop, before the most appropriate treatment can be chosen. In regions with higher hair density, lower fluences have been found to prevent pooling of the heat. However, others have claimed a poor correlation between the area tested with test spots, and the area actually being treated [82]. It has been suggested that the lack of correlation between test spots and treatment area is due to pretreatment sun exposure.
In many reports of laser hair removal with lighter skin color, the best results are often seen in those patients who develop perifollicular edema. However, in patients with darker skin, if perifolliclar erythema and edema lasts for longer than a few minutes or hours, this may be a sign that the fluence will need to be lowered to prevent epidermal thermal damage [5]. An increase in pain levels has also been used to monitor epidermal damage [61].
The safest hair removal systems to treat Fitzpatrick types, IV-VI are the long-pulsed Nd:YAG (1064 nm) and the long-pulsed (>100 ms) diode laser (810 nm) [83]. The use of aggressive cooling is important with the treatment of skin types VI with the diode laser [84]. In darker-skinned individuals selected for laser treatment, reports of side effects are found to have been minimized, if individuals with a history of keloids or hypertropic scarring are treated cautiously [85].
The highest satisfaction of all individuals undergoing laser treatment has been reported for those who have a clear understanding of the outcome of the long-term reduction in hair afforded by this treatment [86]. The lower fluence required for safe treatment of patients with darker skin types may mean that more treatments are required to reach the desired outcome [87, 108]. It is believed that treatments every four to eight weeks will insure the highest results. In treating subjects with darker skin, it is best to avoid crusting, blistering, or scabbing after treatment [75]. In the event that these side effects do occur, topical antibiotic or corticosteroids have been used [5].