Scientific validation of clinical visual scales and Antera 3D™ consistency with derived measurements in the assessment of infantile haemangioma after laser therapy.

BACKGROUND: Laser therapy is a treatment for infantile haemangiomas. The efficacy of laser therapy for red lesions is determined by visual evaluation; however, this assessment is inaccurate and lacks objectivity. OBJECTIVE: To scientifically validate the consistency between pre- and post-treatment visual assessment grades for infantile haemangioma treated with pulsed dye laser (PDL) and the values calculated from images obtained with Antera 3D™. METHODS: This study involved 81 cases of infantile haemangiomas treated with PDL alone from 2012 to 2015 and with Antera 3D™ images of the lesions. Using images obtained before treatment and 4-6 weeks after the last treatment, the lesions were rated using a visual four-step scale. Ratings were categorised as Poor/Fair/Good/Excellent by the degree of improvement in the red colour tone. The red colour ratio was calculated using the haemoglobin distribution in the lesion and surrounding skin, and the improvement difference and improvement rate were then obtained. The correlation between the improvement difference and improvement rate, and visual evaluation was statistically analysed. RESULTS: No serious adverse effects were observed, with an average of 4.3 treatments per patient; 60.1% of the patients achieved Good/Excellent results. There were statistically significant differences in the post-treatment red colour ratio and improvement ratio in each category after visual evaluation classification. The improvement rate and the four visual grades were statistically correlated. CONCLUSION: This study confirmed the scientific validity of visual evaluation and the evaluation criteria calculated from Antera 3D™. This method could objectively determine treatment effectiveness.

Multiple Bowen's disease due to long-term narrow-band ultraviolet B phototherapy: A case report and literature review.

OBJECTIVE: By presenting a case study on multiple instances of Bowen's disease and the consistent use of narrow-band ultraviolet B (NB-UVB) phototherapy over a three-year period, our aim is to enhance the comprehension of domestic clinicians regarding the disease. Additionally, we seek to review existing literature, encouraging dermatologists to consider clinical secondary primary lesion diagnoses. METHOD: Our approach involves analyzing a diagnosed case of multiple Bowen's disease, examining clinical manifestations, histopathology, imaging results, and treatment methods related to NB-UVB phototherapy. We aim to facilitate discussion and understanding through a comprehensive literature analysis. RESULTS: An elderly male with a 30-year history of psoriasis vulgaris initiated continuous NB-UVB therapy three years ago. A year later, he developed red patches and plaques with distinct borders and scaly surfaces on his face, trunk, lower extremities, and scrotum. Histopathological examination confirmed Bowen's disease. Treatment involved liquid nitrogen cryotherapy, with no recurrence observed during the one-year follow-up. CONCLUSION: This case highlights that Bowen's disease, typically solitary, can manifest as multiple instances, especially in individuals with a history of psoriasis vulgaris. While NB-UVB stands as the primary treatment for psoriasis vulgaris, caution is warranted due to the potential risk of skin tumor induction with prolonged high-dose usage. Clinicians should be vigilant in monitoring and assessing the long-term implications of such therapies.

Clinical, histopathological and immunohistochemical evaluation of ultraviolet A1 treatment in early-stage mycosis fungoides.

BACKGROUND/PURPOSE: Mycosis fungoides (MF) is the most common variant of cutaneous T-cell lymphomas primarily involving the skin. Early-stage MF is characterised by non-specific skin lesions and non-diagnostic biopsies. While skin-focused treatments, such as PUVA and narrowband UVB (nbUVB), are the most frequently recommended treatments, the UVA1 efficacy has been researched in recent years. The purpose of this study was to evaluate the clinical, histopathological and immunohistochemical aspects of UVA1 treatment in patients with early-stage MF. METHODS: The modified severity weighted assessment scale (mSWAT) was used for total skin body scoring before and after treatment. Skin punch biopsies were taken from the patients before and after treatment. UVA1 therapy was performed five times each week. RESULTS: This study included 26 patients with early-stage MF. The total number of UVA1 sessions varied between 15 and 34. Complete response was observed in 8 (30.8%) of 26 patients (30.8%). The median mSWAT score decreased statistically significantly from 7.1 to 2.0 after treatment (p < .001). Histopathological complete response was observed in 2 (9.5%) of 21 patients. A statistically significant decrease in dermal interstitial infiltrate was observed on histopathological examination after treatment (p = .039). Epidermal CD4/CD8 levels decreased statistically significantly higher from a median of 2.5-1.2 in the complete clinical response group after treatment (p = .043). CONCLUSION: According to our results, UVA1 treatment has an effect on early-stage MF in terms of clinical, histopathological and immunohistochemistry.

A retrospective study of 1064-nm Q-switched Nd:YAG laser therapy for acquired bilateral nevus of Ota-like macules.

BACKGROUND: The therapeutic efficacy of laser treatments for acquired bilateral nevus of Ota-like macules (ABNOM) varies among studies, and few studies have evaluated the factors affecting therapeutic effects. AIMS: To evaluate the efficacy and safety of 1064-nm Q-switched Nd:YAG laser (QSNYL) therapy for ABNOM and to identify the factors influencing the outcome. METHODS: A total of 110 patients with ABNOM were retrospectively evaluated and received two-to-nine treatment sessions. The effects of different factors on the therapeutic effect were analyzed on the basis of the number of treatments, age at first treatment, skin type, lesion color, affected area, number of lesion sites, and presence of concomitant melasma. RESULTS: The curative effect was positively correlated with the treatment time and negatively correlated with the increasing age at first treatment (p < 0.05). The curative effect was better in patients with skin type III than those with type IV ( p < 0.05) and in patients with a lesion area of less than 10 cm2 than those with a larger affected area (p < 0.05). Additionally, the treatment effect was poorer in patients with concomitant melasma (p < 0.05). The treatment effect was not significantly correlated with the lesion color or number of affected sites (p > 0.05). Eleven patients (10%) developed postinflammatory hyperpigmentation (PIH). CONCLUSIONS: Early and repeated QSNYL therapy achieved satisfactory results for ABNOM. The risk of PIH after laser treatment is highest among patients with older age, darker lesion color, and darker skin color. For patients with ABNOM with concurrent melasma, low-energy laser therapy is recommended to reduce the risk of melasma aggravation.

Nb-UVB and PUVA therapy in treating early stages of Mycosis Fungoides: A single-center cross-sectional study.

INTRODUCTION: Mycosis fungoides (MF) and Sezary Syndrome are the most common forms of cutaneous T-cell lymphoma. Early-stage MF is known to have an indolent behavior, and the EORTC guidelines recommend treating patients with skin-directed therapies, such as phototherapy, instead of systemic therapies. Phototherapy is a popular therapeutic option, with two commonly used light sources-PUVA and narrow band-nb UVB. PUVA is less commonly used due to its potential carcinogenic role, but it has systemic effects, while nb-UVB has mostly skin-limited effects. There is ongoing debate regarding the role of UVB light, and in 2021, the Cutaneous Lymphoma Italian Study Group reached a consensus on technical schedules for NB-UVB and PUVA for MF. This study aims to analyze and compare the efficacy of the two phototherapy options in treating early-MF patients. MATERIALS AND METHODS: The study included patients diagnosed with stage IA/B MF in the last 10 years, who had at least 12 months of follow-up data and a minimum of 24 phototherapy sessions (PUVA or nb UVB) and treated with topical steroids apart from phototherapy. RESULTS: Results showed that the two phototherapy options were similarly effective in treating early MF, with no significant differences in clinical response, although PUVA was associated with more adverse effects. CONCLUSIONS: The study provides valuable insights into the use of phototherapy in early MF, and the results can be used to guide treatment decisions and improve patient outcomes.

Predictors of adherence to Narrowband ultraviolet B first-month treatment dosage plan.

BACKGROUND: The adherence to a narrowband ultraviolet B (NB-UVB) treatment plan is derived, in large part, from the patient's skin tolerance to the phototherapy dose. At present, the initial and first-month incremental phototherapy doses are determined prior to treatment initiation based on the patient's Fitzpatrick skin phototyping. OBJECTIVES: To identify variables that predict adherence to NB-UVB first-month treatment dosage plan. METHODS: Charts of 1000 consecutive patients receiving NB-UVB at a hospital-based phototherapy unit were retrospectively analyzed. We included patients receiving NB-UVB for atopic dermatitis, psoriasis, vitiligo, and mycosis fungoides. The first-month NB-UVB treatment plan was determined based on the patient's Fitzpatrick phototype. Adherence to treatment was defined as receiving at least 80% of the planned first-month cumulative dose. We compared adherent vs. non-adherent patient groups for age, sex, Fitzpatrick phototype, presence of freckles, nevus count category, and type of dermatological disease. RESULTS: The study included 817 eligible patients, mean age 40 (2-95) years; 54% men; 32% had Fitzpatrick phototype I-II. Distribution by diagnosis was atopic dermatitis (29%), psoriasis (27%), vitiligo (23%), and mycosis fungoides (21%). Adherence to NB-UVB treatment plan was observed in 71% of patients. Adherence decreased with age, with 7% decrease per year (P = 0.03) and was higher among mycosis fungoides patients (77.3%) compared to all other diagnoses (69.8%; P = 0.02). CONCLUSIONS: Adherence to NB-UVB treatment may be related to age and diagnosis. Fitzpatrick phototype-based first-month treatment plans should be modified accordingly.

Aiming to personalized laser therapy for nevus of Ota: melanin distribution dependent parameter optimization.

Aiming to the personalized laser therapy of nevus of Ota (NO), a local thermal non-equilibrium model was employed to optimize laser wavelength, pulse duration, and energy density under different melanin depth and volume fraction. According to our simulation, the optimal pulse duration is between 15 and 150 ns to limit heat transfer inside the hyperplastic melanin, and 50 ns is recommended to decrease the energy absorption by normal melanin in epidermis. Correlations of the minimum and the maximum energy densities are proposed with respect to melanin depth and volume fraction for the 755-nm and 1064-nm lasers. For the same NO type, the therapy window of the 755-nm laser is larger than that of 1064-nm. For NO with shallow depth or low volume fraction, the 755-nm laser is recommended to make the treatment more stable owing to its lager therapy window. For deeper depth or higher volume fraction, the 1064-nm laser is recommended to avoid thermal damage of epidermis. Through comparison with clinical data, the optimized laser parameters are proved practicable since high cure rate can be achieved when energy density falls into the range of predicted therapy window. With developing of non-invasive measurement technology of melanin content and distribution, personalized treatment of NO maybe possible in the near future.

Efficacy of narrowband UVB phototherapy in early-stage mycosis fungoides in Iranian patients.

Narrowband UVB (NB-UVB) has been shown to be effective for the treatment of early mycosis fungoides (MF) in light-skinned patients, but the effect of NB-UVB on patients with darker skin phototypes needs further investigation. The aim of this study was to evaluate the effect of NB-UVB in the treatment of early-stage MF in Iranian patients. In this retrospective study, 24 patients with the diagnosis of early MF (9 stage AI, 15 stage IB) were enrolled. All patients were treated with NB-UVB phototherapy 2-3 times weekly. After achieving complete response, a maintenance treatment was recommended. The response rate, side effects, and recurrence rate in the follow-up period were assessed. The follow-up period was ranged 6 to 24 months. Ten patients (41.7%) had complete remission after a mean number of 42.9 treatment and mean cumulative dose of 58.11 J/cm2. Twelve patients (50%) had partial response, and 2 patients (8.3%) had no response. After discontinuation of maintenance treatment, 4 of 10 patients (40%) with complete remission relapsed within a mean of 5 months. Side effects were limited to erythema (12.5%) and hyperpigmentation (4%). NB-UVB is a safe and effective method for the treatment of early MF, but it seems that more treatment sessions and higher doses of NB-UVB are required for darker skin phototypes.

Risk of skin cancer after ultraviolet phototherapy in patients with vitiligo: a systematic review and meta-analysis.

BACKGROUND: Although ultraviolet (UV) phototherapy is an effective treatment for vitiligo, its effect on the risk of skin cancer remains controversial. AIM: To investigate the association between UV phototherapy and skin cancer risk in patients with vitiligo. METHODS: A systematic review was performed for studies published before 5 May 2021 in the PubMed, Embase, Web of Science and Cochrane Library databases. The primary outcome was the association of UV phototherapy with the risk of skin cancer in patients with vitiligo. A meta-analysis with a random-effects model was conducted. RESULTS: Five retrospective cohort studies covering a total of 228 607 patients with vitiligo (110 038 who had been treated with UV phototherapy and 118 569 patients who had not) were included in the meta-analysis. The risk of nonmelanoma skin cancer [Mantel-Haenszel risk ratio (MHRR) = 0.95; 95% CI 0.44-2.05] and melanoma (MHRR = 1.11; 95% CI 0.33-3.82) did not significantly increase after phototherapy in patients with vitiligo. In the subgroup analysis, we also found no significant association between phototherapy with narrowband UVB phototherapy specifically and risk of skin cancer in patients with vitiligo. There was no significant difference in risk of skin cancer between patients from Europe and those from East Asia and the risk was not affected by the number of narrowband UVB phototherapy sessions. CONCLUSIONS: The findings of this systematic review and meta-analysis suggest that UV phototherapy is a safe treatment for vitiligo with no significant risk of skin cancer.

Survival Benefit of Guideline-Concordant Postoperative Radiation for Local Merkel Cell Carcinoma.

BACKGROUND: Postoperative radiation therapy (RT) for early-stage Merkel Cell Carcinoma (MCC) decreases the risk of locoregional recurrence and improve overall survival. However, concordance with RT guidelines is unknown. MATERIALS AND METHODS: The National Cancer Database was queried for stage I/II MCC patients receiving surgical intervention from 2006-2017. The cohort was stratified by patients who had and did not have indication(s) for adjuvant RT of the primary tumor site based on National Comprehensive Cancer Network guidelines. We captured the use of RT, patient demographics, socioeconomic characteristics, and clinical characteristics. Logistic regression, Kaplan-Meier method, and propensity score weighted Cox proportional hazards model examined associations and survival benefits of RT. RESULTS: 2,330 stage I/II MCC patients underwent surgical intervention. 1,858 (79.7%) met National Comprehensive Cancer Network criteria for RT of the primary tumor site, of which 1,062 (57.2%) received RT. 472 (20.3%) did not meet criteria for RT, of which 203 (43.0%) received RT. Five-year overall survival advantage was identified for patients who received RT when it was indicated (P < 0.003). There was no evidence of overall survival advantage when patients received guideline-discordant RT (P = 0.478). CONCLUSIONS: Surgical resection with adjuvant RT of the primary tumor site has an overall survival benefit for local MCC when patients meet criteria for RT. This study found a group who received guideline-discordant RT with no survival advantage. Further investigation is warranted to identify the socio-demographic and oncologic reasons for guideline discordance in the treatment of MCC for both under- and over-treatment.

Novel Application of the 730 and 785 nm Picosecond Titanium Sapphire Lasers for the Treatment of Nevus of Ota.

BACKGROUND AND OBJECTIVES: Nevus of Ota is a benign dermal melanocytosis that may pose significant psychosocial distress to patients. Q-switched nanosecond lasers have traditionally been considered the first-line treatment but pain, bleeding, and postinflammatory pigmentary alteration are common adverse effects. Picosecond devices have been increasingly used to treat nevus of Ota with promising results. We present two cases demonstrating novel applications of the 730 and 785 nm picosecond titanium sapphire lasers for the treatment of nevus of Ota in two patients with types III and IV skin. STUDY DESIGN/MATERIALS AND METHODS: A 730 and 785 nm picosecond titanium sapphire laser with pulse durations of 250 and 300 picoseconds, respectively, were used to treat two cases of nevus of Ota. Four to seven treatment sessions were conducted at monthly intervals, and follow-up evaluation was performed 1-3 months following the final treatment session. RESULTS: Both cases demonstrated greater than 75% clearance following treatment. There were no adverse events or pigmentary alteration noted as a result of picosecond titanium sapphire laser treatment. CONCLUSIONS: The 730 and 785 nm picosecond titanium sapphire lasers are safe and effective for the treatment of nevus of Ota. Lasers Surg. Med. 00:00-00, 2021. © 2021 Wiley Periodicals LLC.

Risk of Skin Cancer among Patients with Chronic Kidney Disease Treated with Ultraviolet B Phototherapy for Uraemic Pruritus: A Nationwide Cohort Study.

The safety of ultraviolet B (UVB) phototherapy with respect to cutaneous carcinogenesis has not been established for patients with chronic kidney disease. To investigate this issue, a nationwide cohort study of 10,805 patients with advanced chronic kidney disease was conducted using data from the National Health Insurance of Taiwan, the Taiwan Cancer Registry, and the national death registry. After a median follow-up of 75 months, 16 of 2,161 patients in the UVB group and 63 of 8,644 patients in the non-UVB group developed skin cancers. Compared with the non-UVB group, patients in the UVB group did not show an increased risk of skin cancer (hazard ratio 1.066; 95% confidence interval 0.584-1.944), non-melanoma skin cancer (hazard ratio 1.067; 95% confidence interval 0.571-1.996), or cutaneous melanoma (hazard ratio 1.009; 95% confidence interval 0.115-8.879). In addition, patients who received more UVB phototherapy did not show an increased risk of skin cancer. UVB phototherapy appears to be a safe treatment for uraemic pruritus in patients with chronic kidney disease.

Comparative transcriptome analysis of gene expression patterns on B16F10 melanoma cells under Photobiomodulation of different light modes.

Cutaneous melanoma is one of the aggressive cancers. Recent studies have shown that Photobiomodulation (PBM) can inhibit the proliferation of melanoma cells. However, it is not clear that the effect of PBM light mode on the inhibition of melanoma cells. Herein, we investigated the difference of influence between continuous wave (CW) and Pulse PBM on B16F10 melanoma cells. Our results suggested that Pulse mode had a more significant inhibition on the viability of B16F10 melanoma cells than CW mode under the PBM light parameter of wavelength, dose, and average irradiance at 457 nm, 1.14 J/cm2, and 0.19 mW/cm2. Besides, we revealed the differentially expressed genes of B16F10 melanoma cells under the various treatments of PBM light mode (not PBM treatment, CW mode, and Pulse mode) by RNA sequencing. Together, our data suggested that Pulse-PBM can improve the effect of PBM on cells significantly and there may be different molecular mechanisms between Pulse and CW mode including anti-proliferative and cell necrosis. The study shed new light on investigating the molecular mechanisms of various PBM light modes on B16F10 melanoma cells.

Long-Term Follow-Up for Q-Switched Nd:YAG Treatment of Nevus of Ota: Are High Number of Treatments Really Required? A Case Report.

Objective: Q-switched laser is considered a gold standard treatment for Nevus of Ota (NO). We report how few laser sessions in long intervals of time may achieve satisfying outcomes reducing the rate of possible procedure-linked side effects such as burning, cornea injuries, or hyperpigmentation. Background: NO represents a congenital dermal melanocytosis in the trigeminal distribution majorly occurring in Asian individuals. Multiple reports have shown efficacy and safety of Q-switched laser for the treatment of this condition, but they were based on an empiric regimen, often leading to unnecessary overtreatments. At the best of our knowledge, no long-term follow-up observations of single laser sessions have been conducted to assess the proper intervals and number of treatments. Materials and methods: A 36-year-old Asian woman, Fitzpatrick skin type IV with clinical diagnosis of NO, was treated with 1064 nm 6 ns Q-switched laser one session per year for a total of two sessions. Clinical result was valued by two physicians independently using standardized and polarized light. No use of general anesthesia or sedation was needed in our experience. Corneal shields have been used. Results: After only two sessions of the Q-switched laser performed 1 year apart, the result was excellent with a 95% of clinical response. No side effect was observed. Conclusions: In our experience, Q-switched Nd:YAG laser is an effective treatment for NO with no necessity of high number of treatments. A larger population is needed to confirm this preliminary result.

Hypopigmented Mycosis Fungoides: A Clinical and Histopathology Analysis in 9 Children.

BACKGROUND: Hypopigmented mycosis fungoides (HMF) is an uncommon variant of mycosis fungoides. AIMS: To study the clinical and histopathology presentation in children with HMF. METHOD: We reviewed 9 children diagnosed with HMF. The clinical data were collected and analyzed. RESULT: Eight boys and 1 girl were included, with a median onset age of 7.4 year old and median age of diagnosis of 10.5 year old. Multiple hypopigmented patches were observed in all patients, and 5 patients exhibited multiple scaly erythema at the center of hypopigmented patches. Histopathology showed atypical lymphocytes with hyperchromatic, irregular, and cerebriform nuclei, infiltrated in the epidermis and dermis. Pautrier's microabscesses was noted in 6 of 9 patients, and papillary dermal fibroplasia was noted in 6 of 9 patients. CD8 predominance was detected in 4 of 6 patients. Four patients were simultaneously subjected to skin biopsy on hypopigmented patches and scaly erythema simultaneously. Compared with hypopigmented specimens, erythema biopsy detected deeper and denser infiltration of atypical lymphoid cells in 3 of 4 patients, higher CD4+/CD8+ ratio in 4 of 4 patients, more CD5 loss in 2 of 4 patients, and more CD7 loss in 2 of 4 patients. TCR gene monoclonal rearrangement was detected in 2 of 5 patients. Narrowband ultraviolet B phototherapy was applied in 7 patients. One of 7 patients achieved complete response, and 6 of 7 patients achieved partial response. No recurrence was noted with the median follow-up period of 6 months. CONCLUSION: HMF could occur in young patients, with indolent and benign course. HMF could gradually seem as scaly erythema based on hypopigmented patches. The histopathology indicated a more advanced stage of the scaly erythema lesions than hypopigmented patches.

Acute and sub-acute toxicity profile of ultra-hypofractionated low-dose total skin electron beam with two 4 Gy fractions for cutaneous T cell lymphoma.

PURPOSE: Low-dose total skin electron beam therapy (TSEBT) over 3 weeks has proved to be a safe and effective treatment for cutaneous T cell lymphomas (CTCL). In this prospective trial, we examined the feasibility of ultra-hypofractionated low-dose TSEBT regimen in two fractions with 4 Gy combined with systemic therapy to minimize the number of visits to radiation centers. PATIENTS AND METHODS: Six patients with mycosis fungoides (MF) or Sézary syndrome (SS) received TSEBT with a total radiation dose of 8 Gy in two fractions between April 2020 and June 2020. Patient and treatment characteristics, tumor burden, the impact on the quality of life using Skindex-29 questionnaires, and acute toxicities were analyzed. RESULTS: During TSEBT, all patients developed grade 1 toxicities while two patients developed grade 2 toxicities. One patient experienced sepsis. The most common adverse effects were erythema and edema. All grade 2 toxicities regressed after 4 weeks following TSEBT. Based on the reported symptoms measured by Skindex-29, we detected a significant reduction in total Skindex-29 score after 8 weeks of radiation (P = 0.03), particularly in the symptoms (P = 0.01) and emotional domains (P = 0.04). CONCLUSION: Ultra-hypofractionated low-dose TSEBT followed by systemic therapy seems to be a safe and feasible alternative to conventional fractionated TSEBT for patients with MF/SS. The skin tumor burden and the health-related quality of life have been significantly improved within 8 weeks following radiotherapy.

A Prospective, Split-Face, Randomized Study Comparing Picosecond to Q-Switched Nd: YAG Laser for Treatment of Epidermal and Dermal Pigmented Lesions in Asians.

BACKGROUND: Whether picosecond lasers outperform Q-switched lasers in treating pigmented lesions has not been clearly evaluated. OBJECTIVE: To compare the efficacy and safety of picosecond and Q-switched lasers in treating epidermal and dermal pigmented lesions in Asians. METHODS: Eight subjects with lentigines and 6 subjects with acquired bilateral nevus of Ota-like macules were enrolled. Subjects was randomly treated with a picosecond laser on one side of the face and a Q-switched laser on the other side. Subjective assessments on pigment clearance, and adverse effect were obtained at Weeks 0, 4, 12, and 24 after the final treatment. RESULTS: Clinical improvement differed between the 2 laser systems at Week 4 (p = .034), Week 12 (p = .039), and Week 24 (p = .027), with 85.7% of picosecond and 57.2% of Q-switched laser sites showing >50% improvement at 6 months. There was no significant difference in the incidence of side effect and healing time, but picosecond laser was significantly associated with a lower treatment discomfort (p = .05). CONCLUSION: The picosecond laser seems to be more effective and better tolerated than Q-switched laser for the treatment of pigmented lesions in Asians.

Successful and quick treatment of nevus of Ota with 755nm picosecond laser in Chinese.

Nevus of Ota, also known as nevus fusco-caeruleus ophthalmo-maxillaris, is a benign dermal melanocytosis. In the past, this disease was usually treated by Q-switched laser therapy, but the course of treatment was relatively long. In recent years, it has been reported that 755nm picosecond laser, which was firstly reported to treat tattoos, is also effective in the treatment of nevus of Ota. Here, we report six cases of nevus of Ota which were treated with 755nm picosecond laser in Chinese people. We find amazingly that these lesions almost disappeared after only one or two sessions of treatment.