Treatment of nevus of Ota with 1064 nm picosecond Nd:YAG laser: A retrospective study

Abstract

Nevus of Ota has been successfully treated by lasers. Currently, 1064 nm picosecond Nd:YAG lasers have become available for the treatment of pigmented disorders. However, there are few studies concerning the application of 1064 nm picosecond Nd:YAG laser in nevus of Ota. This study aimed to evaluate the efficacy and safety of a 1064 nm picosecond Nd:YAG laser for the treatment of nevus of Ota. We conducted a retrospective analysis of Chinese patients with nevus of Ota who had been treated with a 1064 nm picosecond Nd:YAG laser. Those who had any other laser treatment during the period of picosecond laser treatment were excluded. Via a visual analog scale for percentage of pigmentary clearance in standard photographs, the treatment efficacy was assessed by three blinded physician evaluators. A total of 16 subjects were included in this retrospective study. The average age at the beginning of treatment was 16.87 years old (range of 4 months to 59 years), and all patients were of Fitzpatrick skin type IV. Total treatment ranged from 1 to 5 sessions.A 1064 nm picosecond Nd:YAG laser with a mean fluence of 1.8-4.3 J/cm 2 was used at 3-12 month intervals. The mean efficacy score for all 16 patients was 2.56 after one session, and the mean efficacy score of 13 patients who completed two sessions and nine patients who completed three sessions were 3.15 and 3.51, respectively.

Wavelength‐dependent threshold fluences for melanosome disruption to evaluate the treatment of pigmented lesions with 532‐, 730‐, 755‐, 785‐, and 1064‐nm picosecond lasers

“…The results of the calculated incident fluences were consistent with irradiation parameters that achieved favorable clinical results for pigmented lesions treated with picosecond lasers in patients with Fitzpatrick skin types III or IV 21,22,42–49 . Table 4 summarizes the calculated and clinical irradiation parameters and their results for the treatment of epidermal and dermal lesions.…”

“…For the 1064-nm picosecond laser, the calculated incident fluence for melanosomes distributed in the dermis was consistent with the clinical parameter I. 49 By contrast, the calculated fluence was slightly higher than the clinical parameters J 21 and K, 21 where excellent clearance was not achieved, suggesting that increasing the fluences from the clinical parameters may result in more effective disruption of abnormal dermal melanosomes. In addition, when compared to clinical parameters of nanosecond lasers, a spot size remained almost similar, but the calculated incident fluences of picosecond lasers were approximately twice lower than the incident fluence used in nanosecond laser treatments.…”

“…The results of the calculated incident fluences were consistent with irradiation parameters that achieved favorable clinical results for pigmented lesions treated with picosecond lasers in patients with Fitzpatrick skin types III or IV. 21,22,[42][43][44][45][46][47][48][49] Table 4 summarizes the calculated and clinical irradiation parameters and their results for the treatment of epidermal and dermal lesions. For the 532-nm picosecond laser, the incident fluence calculated for melanosomes located in the epidermis was mostly consistent with the clinical parameters A, 42 B, 43 and C. 22 The study C reported histological images of solar lentigines irradiated with a 532-nm picosecond laser at a spot size of 4 mm and a fluence of 0.5 J/cm², which matched with the calculated irradiation parameters.…”

Update on lasers in pediatric dermatology: how primary care providers can help patients and families navigate appropriate treatment options and timelines

“…1064 nm Q-switched Nd : YAG has also been shown to be well tolerated and effective in skin types V and VI, although there is risk of guttate hypopigmentation [23]. 755 nm picosecond Alexandrite and 1064 nm picosecond Nd : YAG have both been shown to be well tolerated and effective in treatment of Nevus of Ota [24,25]. 755 nm picosecond Alexandrite has demonstrated superiority to 755 nm Q-switched Alexandrite in terms of treatments needed, as well as posttreatment erythema and duration of postinflammatory hyperpigmentation after treatment [24][25][26][27].…”

“…755 nm picosecond Alexandrite and 1064 nm picosecond Nd : YAG have both been shown to be well tolerated and effective in treatment of Nevus of Ota [24,25]. 755 nm picosecond Alexandrite has demonstrated superiority to 755 nm Q-switched Alexandrite in terms of treatments needed, as well as posttreatment erythema and duration of postinflammatory hyperpigmentation after treatment [24][25][26][27]. Rates of recurrence after treatment are variable and depend on the number of treatments and clearance achieved, but clearance of 85% or higher is associated with a lower risk of recurrence [28 & ].…”