Efficacy and Safety of 577-nm Yellow Laser in the Treatment of Pigmented Epidermal Lesions.

OBJECTIVES: Freckles and lentigines are common pigmented problems which not only cause substantial cosmetic morbidity but also create psychosocial concern. The available modalities for the treatment of pigmented lesions are often unsatisfactory for patients, require a long treatment period, and often cause skin irritation. With the advent of lasers, safe and effective treatment options for epidermal pigmentation have become more varied for different Fitzpatrick skin types. We aimed to evaluate the efficacy and safety of 577-nm yellow laser in the treatment of pigmented epidermal lesions. METHODS: This study was carried out on 50 patients presented with pigmented epidermal lesions (25 presented with freckles and 25 presented with lentigines). Each patient received four treatment sessions with a 577-nm diode laser at 2-week intervals. RESULTS: There was significant improvement in freckles and lentigines, as 23 out of 50 patients showed marked improvement, 11 patients showed moderate improvement, 10 patients showed mild improvement, and only six patients had no changes. Moreover, 23 patients were very satisfied, 18 patients were satisfied, and nine patients were not satisfied. As regards the safety of the 577-nm yellow laser, there was no significant adverse effect among patients except pain, erythema, and hyperpigmentation, which resolved within one month after treatment. CONCLUSIONS: This study showed that the 577-nm yellow laser is an effective, safe, and well-tolerated device in the treatment of freckles and lentigines.

Correlation between the efficacy of picosecond-domain laser treatment for solar lentigo and the vascularity in the upper dermis using optical coherence tomography angiography in Asian women.

OBJECTIVES: The purpose of this study was to noninvasively confirm the characteristics of the dermal vasculature in patients with solar lentigo (SL) and determine any association with the efficacy of picosecond-domain laser (PSL) treatment. METHODS: Thirteen facial SL lesions in 11 Asian female patients were included in this study and evaluated over 12 weeks. An Nd:YAG laser was used at 532 nm and 750 ps. Skin color and morphological structure were evaluated by ANTERA-3D® and optical coherence tomography (OCT), respectively. To analyze the vascularity in the upper dermis, an OCT angiography (OCTA) algorithm was applied to the OCT data. RESULTS: After PSL treatment, significant improvement in both hyperpigmentation and abnormally thickened epidermis was observed, but the efficacy varied for each lesion. There was a significant correlation between the change in the melanin index due to PSL treatment and preoperative vascular density in the upper dermis. CONCLUSIONS: To the best of our knowledge, this is the first report to demonstrate a correlation between the efficacy of PSL treatment of SL lesions and the vascularity in the upper dermis. Methods to evaluate the vasculature in the upper dermis may be useful for preoperative prediction of the efficacy of PSL treatment for SL lesions.

Picosecond 755-nm alexandrite laser treatment for oral lentiginosis in Peutz-Jeghers disease.

We present the case of a 16-year-old boy with Peutz-Jeghers disease with successful treatment of oral lentiginosis with one session of picosecond 755-nm alexandrite laser. To date, only in one other article picosecond laser is used for lentiginosis in Peutz-Jeghers disease. Other therapeutical options include Q-switched 755-nm alexandrite, 1064-nm Nd:YAG, 532-nm KTP-laser, ruby and intense pulsed light, which generally require more sessions, are less pigment-selective and have overall worse results than picosecond laser treatment.

Clinical Evaluation of Safety and Efficacy of a 670-nm Picosecond Laser for Treatment of Benign Pigmented Lesions in Asians.

BACKGROUND: Picosecond lasers are increasingly being investigated in treating pigmentation disorders because they may provide better treatment efficacy and comfort compared with nanosecond lasers. OBJECTIVE: This study aims to evaluate the efficacy and side effect of a novel 670-nm picosecond laser in the removal of benign pigmented lesions (BPLs) in individuals with Fitzpatrick skin types (FST) III and IV. MATERIALS AND METHODS: Fifteen subjects with solar lentigines and 7 subjects with ABNOMs received a single treatment with a 670-nm picosecond laser. Blinded physicians assessed the pigment clearance using a 5-category grading system scale. All subjects were evaluated at 1 month, 3 month, and 6 month after a single treatment. Adverse events were recorded at every follow-up visit. RESULTS: All subjects with lentigines had complete clearance (95%-100%) of lesions during 3-month follow-up after a single treatment session of 670-nm picosecond laser, whereas 75% of the subjects with ABNOMs noted fair lightning (25%-49%) of lesions. Mild hypopigmentation and hyperpigmentation were observed in 9% and 14% of the subjects, respectively, which resolved within 3 months after the treatment. CONCLUSION: The novel 670-nm picosecond laser is a safe and effective treatment for BPLs in subjects with FST III and IV with low rates of transient adverse effects.

Intraoral atypical lentiginous melanocytic lesion in a pediatric patient.

We present a rare case of intraoral atypical lentiginous melanocytic lesion affecting a pediatric patient, in which the diagnosis of lentiginous junctional melanocytic nevus with cytologic atypia was favored. The main differential diagnosis is lentiginous melanoma, which is a slowly progressing lesion, affecting mainly older adults, and microscopically presenting lentiginous growth pattern of moderately atypical melanocytes, with focal nesting and pagetoid spread. It is strongly recommended that melanocytic lesions showing features of atypical lentiginous growth pattern should be treated with wide excision; however, the impact of these guidelines on pediatric patients needs to be better defined with the report of further cases.

A Prospective Randomized Controlled Study of Oral Tranexamic Acid for the Prevention of Postinflammatory Hyperpigmentation After Q-Switched 532-nm Nd:YAG Laser for Solar Lentigines.

BACKGROUND AND OBJECTIVES: Q-switched (QS) 532-nm Nd:YAG laser is one of the treatment options for solar lentigines (SLs). However, the high incidence of postinflammatory hyperpigmentation (PIH) is concerning, especially in dark-complexioned skin. Tranexamic acid (TA) can decrease melanogenesis and has been used to treat melasma. The aim of this study is to evaluate the efficacy and safety of oral TA for PIH prevention and clearance in patients with SL treated with QS 532-nm Nd:YAG laser. STUDY DESIGN/MATERIALS AND METHODS: Forty patients with SL treated with QS 532-nm Nd:YAG laser were enrolled in this randomized controlled trial. They were randomly assigned to be receive oral TA 1,500 mg daily or placebo for 6 weeks. Results were evaluated by blinded investigators using digital photographs, dermatoscopy, colorimetry, physician grading scores, and patient satisfaction scores at baseline, 2nd, 4th, 6th, and 12th weeks. RESULTS: The incidence of PIH, relative melanin value, lightness index, and clinical improvement scores were not significantly different between the two groups. However, the TA group had a significantly lower incidence of dermatoscopic finding of pigmented granules, which correspond to PIH at 6th and 12th weeks (P = 0.038 and 0.013, respectively). Homogenous light brown pigmentation under dermatoscopy was significantly associated with higher clinical improvement. CONCLUSIONS: Oral TA therapy starting at the first day postlaser treatment is not effective for PIH prevention after QS 532-nm Nd:YAG laser in SL. However, PIH clearance, as assessed dermatoscopically, is significantly improved by oral TA at 6th and 12th week. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

A Prospective Study in the Treatment of Lentigines in Asian Skin Using 532 nm Picosecond Nd:YAG Laser.

BACKGROUND AND OBJECTIVE: To evaluate safety and efficacy of treatment with the picosecond Nd:YAG 532 nm for lentigines in Asian skin. STUDY DESIGN/MATERIALS AND METHODS: This was a prospective, open-label cohort study, using a novel picosecond 532-nm laser for the treatment of facial lentigines. Subjects received up to three laser treatments every 4-6 weeks and were assessed at 4 and 12 weeks after final treatment. Primary endpoint was degree of improvement in lentigines at 12 weeks after the final treatment, assessed by treating investigator based on Physicians Global Assessment. Secondary end-points included degree of improvement in lentigines at 12 weeks after final treatment, assessed by subject (Subject's Global Assessment), and change in mean relative Melanin index (MI) value at 3 months after final treatment as compared to baseline as assessed by mexameter measurement. RESULTS: A total of 20 patients (3 male, and 17 female) of Asian-descent with Fitzpatrick skin type III and IV, with lentigines on the face were included in this study. A total of 89 lesions were treated with the laser setting of 532-nm, 750 picoseconds, fluence of 0.2-0.5 J/cm 2 , and spot size of 4 mm. One hundred and thirty-seven treatment sessions were given in total. Eighteen patients (90%) achieved a moderate to significant improvement at 12-week follow-up based on a 5-grade physician global assessment scale. The improvement rate of relative MI (MI in the lesion minus normal skin) was 33.30 ± 18.71 and 37.63 ± 19.25% at 4- and 12-week follow-up. Post-inflammatory hyperpigmentation (PIH) occurred in 14 of 137 sessions (10.2%), and hypopigmentation occurred in one patient with five lesions (3.6%). CONCLUSION: This study demonstrates that using picosecond Nd:YAG laser 532 nm for removal of solar lentigines in darker skin type appears to be safe and effective. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc. LIMITATIONS: Small study group.

Brimonidine tartrate gel plus topical steroid for the prevention of laser therapy-related postinflammatory hyperpigmentation.

Brimonidine gel, originally approved for the treatment of facial rosacea, causes direct vasoconstriction and possesses extensive utilization in dermatologic fields. A Q-switched (QS) neodymium-doped yttrium aluminum garnet (Nd:YAG) laser is generally used to treat solar lentigo (SL), often leaving unwanted postinflammatory hyperpigmentation (PIH), especially in dark-skinned individuals. A 58-year-old man with Fitzpatrick skin type IV presented to remove solar lentigines from his face. Prior to and after laser treatment, topical brimonidine gel and steroid cream were applied. In this study, we investigated whether topical application of the α-adrenergic receptor agonist brimonidine could reduce PIH after QS laser treatment of lentigine in a dark-skinned patient.

Q-switched double frequency Nd:YAG 532-nm nanosecond laser vs. double frequency Nd:YAG 532-nm picosecond laser for the treatment of solar lentigines in Asians.

Solar lentigines are common pigmentary lesions. Q-switched lasers are effective treatment options but postinflammatory hyperpigmentation (PIH) is common in darker skin. The objective of the study is to compare the efficacy and safety in solar lentigines of Asian skin treated by Q-switched potassium titanyl phosphate (KTP) 532-nm nanosecond laser vs. KTP 532-nm picosecond laser for the treatment of solar lentigines in Asians. Thirty patients with at least 2 solar lentigines on the upper extremities were enrolled. A total of 30 paired lentiginous lesions were randomly treated with a single treatment of either Q-switched KTP 532-nm nanosecond laser vs. KTP 532-nm picosecond laser. In terms of efficacy, mean luminance score was evaluated at baseline, at 6th, and 12th week. Degree of pigment clearance was assessed by a blinded physician and the patients. Satisfaction score was rated by patients using visual analogue scale. Adverse events were also recorded. Twenty-eight patients completed the study. Both lasers showed significant improvement in mean luminance score from baseline (p < 0.05). Likewise, there was no significant difference in pigment clearance between two lasers either assessed by physician or patients. However, patients' satisfaction score was significantly higher with the picosecond laser (p = 0.014). Adverse events and pain were not different between groups. Q-switched KTP 532-nm nanosecond laser and KTP 532-nm picosecond laser are safe and effective for treating solar lentigines in Asians. Based on cost-effectiveness, Q-switched KTP 532-nm nanosecond laser remains the main treatment while KTP 532-nm picosecond laser can be considered as a treatment option.

Subungual atypical lentiginous melanocytic proliferations in children and adolescents: A clinicopathologic study.

BACKGROUND: Most subungual melanocytic lesions in children are benign, but some are difficult to classify due to prominent lentiginous growth and high-grade cytologic atypia. OBJECTIVE: To characterize the clinicopathologic features of these rare lesions. METHODS: Subungual atypical lentiginous melanocytic proliferations from patients <20 years of age were collected for clinical and histopathologic review. Fluorescence in situ hybridization (FISH) was performed when possible. RESULTS: Eleven patients aged 2-19 years had expanding or darkening longitudinal pigmented streak(s) with or without Hutchinson sign. Microscopically, all revealed predominantly single-cell growth, pagetoid scatter, and poor circumscription. Eight (73%) cases showed focal or poor nesting, and 3 (27%) demonstrated confluence. Nuclear enlargement, hyperchromasia, and angulation were present in 8 (73%) cases, 7 (64%) cases, and 6 (55%) cases, respectively. One of 4 cases tested by FISH was positive. Three lesions recurred locally without other adverse outcome. LIMITATIONS: Small sample size and short clinical follow-up. Two cases were examined in partial biopsies only. CONCLUSION: Some subungual melanocytic lesions in children and adolescents are histologically indistinguishable from adult subungual melanoma in situ. While the biologic potential remains elusive, FISH might aid in risk stratification. Awareness of this rare group of lesions is crucial for facilitating future investigation into its biologic behavior.

Comparison of Q-switched Nd: YAG laser and fractional carbon dioxide laser for the treatment of solar lentigines in Asians.

BACKGROUND/OBJECTIVE: Solar lentigines are benign pigmented lesions that occur mostly on sun-exposed areas. Q-switched and ablative lasers are effective for removing these lesions but the high incidence of postinflammatory hyperpigmentation raises concern in darker skin types. The objective of this study is to compare the efficacy and degree of postinflammatory hyperpigmentation with the Q-switched Nd:YAG and fractional carbon dioxide (CO2 ) laser for treatment of solar lentigines in Asians. STUDY DESIGN: Twenty-five Thai patients (skin phototype III-IV) with at least two lesions of solar lentigines on upper extremities were enrolled in this study. Two lesions were randomly selected for the treatment with a single session of Q-switched Nd:YAG or fractional CO2 laser. Outcomes were evaluated using physician grading scale, colorimeter, and patient self-assessment at 6 and 12 weeks after treatment. Side effects were recorded. RESULTS: A total of 532 nm Q-switched Nd:YAG laser showed significant improvement of pigmentation over fractional CO2 laser at 6th and 12th week by both colorimeter assessment and physician grading scale (P < 0.05). No significant difference in postinflammatory hyperpigmentation from both lasers was observed. In terms of patient self-assessment, 80% of the patients treated with 532 nm Q-switched Nd:YAG laser had excellent results compared to 8% in fractional CO2 laser group. However, fractional CO2 laser treatment had faster healing time and less pain score compared to Q-switched Nd:YAG laser. CONCLUSIONS: Q-switched Nd:YAG is superior to fractional CO2 laser for treatment of solar lentigines but requires longer healing time and produces more pain. The incidence of postinflammatory hyperpigmentation was not significantly different with both lasers. Further studies are needed to obtain the proper parameter and the treatment frequency of fractional CO2 laser in solar lentigines.

Laser treatment of solar lentigines on dorsum of hands: QS Ruby laser versus ablative CO2 fractional laser - a randomized controlled trial.

BACKGROUND: Lentigines solares (LS) on the dorsum of hands are often esthetically disturbing. Q-switched ruby laser treatment is highly effective in the treatment of these lesions. Ablative fractional photothermolysis may be a suitable alternative. We compared the Q-switched ruby laser with ablative CO2 fractional photothermolysis for the treatment of solar lentigines. OBJECTIVE: To evaluate the efficacy and side-effects of 694nm Q-switched ruby laser (Sinon) with the ablative 10,600nm CO2 fractional laser (Quantel Excel O2) in an intra-individual side-to-side comparison in the treatment of LS on the dorsum of hands. MATERIAL AND METHODS: Eleven patients were included in the study. The hands of each patient were randomized for treatment with the two laser systems. Three treatment sessions were scheduled at weeks 0, 4 and 8. Evaluations by patients, treating physician and blinded experts were scheduled at weeks 0, 4, 8, 16 and 24. RESULTS: The Q-switched ruby laser was significantly more efficacious than the ablative CO2 fractional laser for removing LS on the dorsum of hands (p = 0.01). CONCLUSION: In this first study on this topic, the Q-switched ruby laser was superior to the ablative CO2 fractional laser in the treatment of lentigines solares on the dorsum of hands.

Effect of an epidermal growth factor-containing cream on postinflammatory hyperpigmentation after Q-switched 532-nm neodymium-doped yttrium aluminum garnet laser treatment.

BACKGROUND: Topical application of epidermal growth factor (EGF) promotes wound healing and may reduce the risk of laser-induced postinflammatory hyperpigmentation (PIH). OBJECTIVE: To investigate the effect of an EGF-containing cream on the incidence of laser-induced PIH. METHODS: Twenty-five Korean patients with senile lentigines were recruited and underwent 532-nm Q-switched Nd:YAG laser treatment. Postoperatively, patients applied either an EGF-containing cream or a control cream to the laser-treated area. Skin color and transepidermal water loss (TEWL) were measured on Days 0, 3, 7, and 35 using a Mexameter and Tewameter, respectively. RESULTS: The EGF-containing cream resulted in a nonsignificant reduction in the laser-induced increase in TEWL (p = .052 on Day 7) but significantly decreased the melanin index and incidence of PIH on Day 35 (p = .031 and p = .027, respectively). CONCLUSION: Epidermal growth factor-containing creams may be an effective measure to prevent laser treatment-induced PIH in Asian patients.

A split-face, evaluator-blind randomized study on the early effects of Q-switched Nd:YAG laser plus Er:YAG micropeel (combined therapy) versus Q-switched Nd:YAG alone in light solar lentigines in Asians.

Solar lentigines are a common sign of aging in Asians, who often asked for treatment. Various lasers, including Q-switched Nd:YAG and Er:YAG, have been adopted, but the results are not always satisfactory, especially for those who are relatively light in color. Our objective was to compare the early effects as well as side effects of Q-switched Nd:YAG laser plus Er:YAG micropeel (combined therapy) with those of Q-switched Nd:YAG laser (QSNY) alone in light solar lentigines in Asians. This was a split-face, evaluator-blind, randomized controlled study. A single session of treatment was performed on Asian patients with light facial lentigines. A combined treatment with QSNY and Er:YAG micropeel was allocated to one half of the face, and QSNY alone to the other half. The response to therapy was evaluated by two independent dermatologists, with standardized photographs taken 2 weeks and 1 month after the laser treatment. Patients' satisfaction and preference in treatment were also assessed. Fifteen patients completed the study and were analyzed. Overall, a reduction in pigment was observed with both treatment arms during the study period. The degree of pigment reduction following combined therapy and QSNY alone was similar at 2 weeks' follow-up ( = 0.433). However, due to the higher incidence of postinflammatory hyperpigmentation (PIH) with combined therapy (73.3 vs 40%), the degree of pigment reduction in the combined side of the face was found significantly lower than that of the QSNY-alone side at 1-month follow-up (P = 0.014). Although our study results show that both combined therapy and QSNY alone are capable of reducing pigmentation, QSNY alone is considered to have more favorable qualities than combined treatment for light solar lentigines in Asians.

Partial unilateral lentiginosis treated with alexandrite Q-switched laser: case report and review of the literature.

Partial unilateral lentiginosis (PUL) is a rare pigmentary disorder characterized by multiple lentigines grouped within an area of normal skin, often in a segmental pattern and appearing at birth or in childhood. There is no established standard treatment for this condition. We present two cases of PUL succesfully treated with alexandrite Q-switched laser. In our cases, this laser proved to be a safe and effective treatment for cosmetically disfiguring lentigines. Special precautions are needed when treating dark-skinned patients because side effects are more likely. We propose that this modality be considered in the treatment of this rare disorder.