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.

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.

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.

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.

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.

Treatment of Laser-Responsive Dermal Pigmentary Conditions in Type III-IV Asian Skin With a 755-nm Picosecond Pulse Duration Laser: A Retrospective Review of Its Efficacy and Safety.

BACKGROUND: Picosecond lasers have become very popular in the treatment of hyperpigmentation. OBJECTIVE: Evaluating the efficacy and safety of picosecond 755-nm laser in treatment of nevi of Ota (NO) and Hori's nevi (HN) in Asians with Fitzpatrick skin Types III/IV. METHODS: A retrospective review of patient records at the National Skin Center, Singapore, from 2015 to 2017. Three independent blinded dermatologists assessed pre-and-post treatment photographs using the physician's global assessment (PGA) score (0-clear, 1-almost clear, 2-mild, 3-moderate, and 4-severe). RESULTS: There were 18 cases of NO and 11 cases of HN. Mean treatment sessions were 2.22 (NO; range 1-6) and 3.82 (HN; range 1-6). In the NO group, mean pre-and-post treatment PGA scores were 3.1 and 1.3, respectively (1.8 point change, p-value 0.0002), and average fluence used was 2.02 J/cm (range: 1.02-2.38). In the HN group, mean pre-and-post treatment PGA scores were 2.6 and 1.1, respectively (1.5 point change, p-value 0.004), and average fluence was 2.08 J/cm (range: 1.98-3.40). Eleven patients (37.9%) experienced postlaser erythema, and 1 (3.4%) patient developed transient postlaser hypopigmentation. No permanent hyper/hypopigmentation was seen. CONCLUSION: The picosecond 755-nm laser is effective in the treatment of dermal pigmentary conditions in Asians with Fitzpatrick skin Types III/IV, with minimal risk of postlaser complications, and compared with the center's past experience with the Q-switched nanosecond 1064-nm laser, results in faster and more effective pigment clearance.

Clinical characteristics and treatment of 52 cases of phakomatosis pigmentovascularis.

Phakomatosis pigmentovascularis is a rare syndrome characterized by widespread capillary malformation and pigmented nevus. The objective of this study was to evaluate its characteristics and treatment. Fifty-two patients presenting between 2003 and 2017 were retrospectively reviewed. Type IIa (port-wine stain and dermal melanocytosis with oculocutaneous involvement) was most common. Systemic involvement was observed in 17.3% and it was not significantly correlated to extent of capillary malformation or pigmented nevus. However, systemic involvement was significantly frequent in patients with nevus of Ota and in patients with pigmented nevus located on the head and neck (P = 0.004 and 0.035, respectively). Capillary malformation was almost cleared in 28.6% of patients using pulsed dye laser, whereas pigmented nevus was almost cleared in 23.7% and completely cleared in 42.1% of patients using Q-switched neodymium:yttrium-aluminum-garnet laser. Treatment outcome score showed significant inverse correlation with the extent of port-wine stain or pigmented nevus (P = 0.047, ρ = -0.308 and P = 0.011, ρ = -0.410, respectively). Pigmented nevus demonstrated better treatment response to lasers than did capillary malformation. Smaller lesions tended to show better treatment outcomes for both capillary malformation and pigmented nevus.

A retrospective analysis of the clinical efficacies and recurrence of Q-switched Nd:YAG laser treatment of nevus of Ota in 224 Chinese patients.

BACKGROUND: Nevus of Ota can be treated successfully using the Q-switched (QS) laser; but few studies are long-term retrospective of the efficacy and influencing factor, studies on the recurrence is even less. PURPOSE: Retrospective analysis of the clinical characteristics and recurrence of QS Nd:YAG laser treatment of nevus of Ota in 224 Chinese patients at Laser Cosmetology Center of Department of Dermatology, the Second Hospital, Xi'an Jiaotong University. METHODS: The data of 224 patients with nevus of Ota were analyzed retrospectively, which included the correlation among lesion color, treatment sessions, gender, age, lesion types and effect, and all patients were followed up for 2-10 years. RESULTS: Higher number of treatment sessions that were conducted using the QS Nd:YAG laser system was positively associated with better responses to treatment. 99.11% of patients acquired more than 75% improvement with an average of 3.7 sessions. Only eight patients (3.57%) who had been completely cleared developed recurrence at the same site as before. CONCLUSION: The treatment of nevus of Ota with QS Nd:YAG laser is safe and effective with rare recurrence.

Successful and safe use of Q-switched lasers in the treatment of nevus of Ota in children with phototypes IV-VI.

OBJECTIVE: Nevus of Ota represents congenital dermal melanocytosis in a trigeminal distribution, most commonly occurring in Asian individuals and other individuals with skin of color. Evidence suggests early treatment is beneficial. Multiple reports have shown efficacy and safety of Q-switched laser treatment in adults. There is little data on children and in non-Asian skin types. This series was done to demonstrate safe and effective use of Q-switched laser therapy in children of multiple skin types. STUDY DESIGN: Retrospective case series. METHODS: This was a chart review of patients under 18 years old who presented to our practice from 2002 to 2015 with a clinical diagnosis of nevus of Ota who were treated with Q-switched lasers (694 and 1,064 nm). Patients were treated without the use of general anesthesia or sedation, and corneal shields were used in appropriate cases. Percentage of improvement as well as side effects were rated by five physicians independently. Improvement, when present, was rated in quartiles (1-25%, 26-50%, 51-75%, and 76-100% improvement). RESULTS: Twenty-four children were included. The average age at the start of treatment was 3.9 years old (range of 3 months to 12.4 years), and patients had Fitzpatrick skin types IV through VI. The mean number of treatments was 9.3. Assessment revealed excellent response (76-100% improvement) in 70% of patients and good to excellent response (51-100% improvement) in 86%. Two patients (8%) had post-inflammatory hyperpigmentation, one of whom also had focal hypopigmentation. CONCLUSION: Treatment of nevus of Ota with Q-switched lasers in children with skin of color, without general anesthesia or sedation, is safe and effective. Early intervention should be encouraged for better efficacy and to prevent psychosocial distress in later childhood and adulthood. Lasers Surg. Med. 50:56-60, 2018. © 2017 Wiley Periodicals, Inc.

Comparison of clinical efficacy and complications between Q-switched alexandrite laser and Q-switched Nd:YAG laser on nevus of Ota: a systematic review and meta-analysis.

Although the application of Q-switched lasers on nevus of Ota (OTA) is well demonstrated, debates about clinical option between Q-switched alexandrite laser (QSA) and Q-switched Nd:YAG laser (QSNY) still remain. This systematic review and meta-analysis estimated the overall successful rate of OTA pigment clearance and complication rate of QSA and QSNY and evaluated which laser could produce a better result. English articles evaluating pigment clearance and complications of QSA and/or QSNY on OTA were screened through predetermined inclusion and exclusion criteria and analyzed. The successful rate of pigment clearance and complication rate of QSA and QSNY were respectively calculated using a random-effects or fixed-effects model, depending on the heterogeneity of the included studies. The successful rate and complication rate of QSA and QSNY were compared statistically. Of the 140 articles searched, 13 met inclusion criteria. Totally, 2153 OTA patients treated by QSA and 316 patients treated by QSNY were analyzed. In QSA and QSNY groups, respectively, the successful rate of OTA pigment clearance was 48.3% (95% confidence interval (CI) 19.9-76.8%) and 41% (95% CI 9.7-72.2%), while the complication rate was 8.0% (95% CI 3.9-12.2%) and 13.4% (95% CI 7.7-19.0%). When compared with QSNY, QSA had a significantly higher successful rate (P = 0.017), and a lower complication rate (P = 0.000). According to this review, QSA may surpass QSNY in treatment for OTA as it had a superior successful rate of pigment clearance and a lower complication rate than QSNY did.

Induction of melasma by 1064-nm Q-switched neodymium:yttrium-aluminum-garnet laser therapy for acquired bilateral nevus of Ota-like macules (Hori nevus): A study on related factors in the Chinese population.

Laser treatment has emerged as a common treatment modality for acquired bilateral nevus of Ota-like macules (ABNOM). To identify the ratio of melasma induction and exacerbation before and after laser therapy for ABNOM and to observe the risk factors related to the induction and exacerbation of melasma by laser therapy, we analyzed related factors of 1268 adult Chinese patients who underwent 1064-nm Q-switched neodymium:yttrium-aluminum-garnet (Nd:YAG) laser (QNYL) treatment using case series and case-control studies. Overall, 24.0% of the ABNOM patients had mixed melasma. Among the ABNOM patients without melasma, after laser therapy the development of melasma was more frequently noted in patients older than 35 years (P < 0.0001), as well in patients whose ABNOM was less than 10 cm(2) (P = 0.027), ABNOM were light (similar to yellow-brown) in color (P = 0.021) and skin types were closer to type IV (P < 0.0001). New melasma lesions also appeared most frequently in the zygomatic region (P < 0.0001). Among the ABNOM patients with melasma, 89.5% experienced worsening of their melasma, irrespective of their related factors above. We concluded that the risk of inducing melasma is great after 1064-nm QNYL treatment in ABNOM patients, and particularly in the patients with both ABNOM and melasma. ABNOM patients should be treated as early as possible and before the age of 35 years.

Treatment of nevus of Ota using low fluence Q-switched Nd:YAG laser.

BACKGROUND: Nevus of Ota, caused by dermal melanocytosis, is cosmetically troublesome in Asian patients. The destruction of dermal melanocytosis using Q-switched laser systems carries a high risk of postinflammatory hyperpigmentation/hypopigmentation. METHODS: To determine the usefulness, safety, and adverse problems of low fluence 1064 nm Q-switched Nd:YAG laser in the treatment of nevus of Ota, 19 Korean patients (five male and 14 female; Fitzpatrick skin type IV) who were clinically diagnosed as having nevus of Ota were enrolled in the present study. Low fluence laser treatments were performed with a collimated Q-switched Nd:YAG laser at intervals of two weeks. The fluence of laser treatments was set at 2.5 J/cm(2) and adjusted based on patient response to the previous treatment session and sensitivity to pain. Treatment was applied until the lesions showed mild erythema. RESULTS: The mean number of total treatment sessions was 17.1 (range 6-32). Among the 19 patients, 18 reached near total improvement, while one patient failed to reach near total improvement after 11 treatment sessions. The mean fluence of treatment was 2.5 J/cm(2) (range 2.0-5.0 J/cm(2) ). Five patients complained of delayed eyelid response. Post-therapy hyperpigmentation was observed in one patient. CONCLUSION: Low fluence 1064 nm Q-switched Nd:YAG laser is an effective modality for the treatment of nevus of Ota with a low incidence of side effects. It is an easy to perform treatment with low downtime.

[Lasers]. / Lasers.

Lasers are a very effective approach for treating many hyperpigmented lesions. They are the gold standard treatment for actinic lentigos and dermal hypermelanocytosis, such as Ota nevus. Becker nevus, hyperpigmented mosaicisms, and lentigines can also be successfully treated with lasers, but they could be less effective and relapses can be observed. However, lasers cannot be proposed for all types of hyperpigmentation. Thus, freckles and café-au-lait macules should not be treated as the relapses are nearly constant. Due to its complex pathophysiology, melasma has a special place in hyperpigmented dermatoses. Q-switched lasers (using standard parameters or low fluency) should not be used because of consistent relapses and the high risk of post-inflammatory hyperpigmentation. Paradoxically, targeting the vascular component of the melasma lesion with lasers could have a beneficial effect. However, these results have yet to be confirmed. In all cases, a precise diagnosis of the type of hyperpigmentation is mandatory before any laser treatment, and the limits and the potential side effects of the treatment must be clearly explained to patients.

A retrospective study of q-switched alexandrite laser in treating nevus of ota.

BACKGROUND: The Q-switched alexandrite laser (QSAL) has been clinically proven to be effective in treating nevus of Ota, but a large-scale retrospective study with long-term follow-up has never been performed. OBJECTIVE: To evaluate the efficacy of the QSAL in treating nevus of Ota, the laser's long-term side effects, complications associated with the treatments, and the recurrence rate. MATERIALS AND METHODS: Eight hundred six patients (651 female, 155 male) with a diagnosis of nevus of Ota who had received a series of QSAL (wavelength 755 nm) treatments were recruited. The typical settings were fluences of 3.8 to 4.8 J/cm(2) and a spot size of 3 mm. Follow-ups were conducted via questionnaire with 590 patients who had completed the treatment at least 3 years earlier. RESULTS: Overall, 93.9% of patients achieved complete clearance after an average of 5.2 sessions. All recurrences (0.8%) appeared beyond the previously treated sites. No long-term adverse effects, including hypopigmentation, hyperpigmentation, textural changes, and malignant transformation, were observed. CONCLUSION: The QSAL is a safe and effective modality for treating nevus of Ota. Recurrence was rare and appeared beyond the previously treated sites. The authors have indicated no significant interest with commercial supporters.

Effect of cold air cooling on the incidence of postinflammatory hyperpigmentation after Q-switched Nd:YAG laser treatment of acquired bilateral nevus of Ota like macules.

OBJECTIVE: To investigate the effect of cold air cooling on the incidence of postinflammatory hyperpigmentation (PIH) after laser treatment in Asian patients. DESIGN: Randomized, controlled, split-face study. SETTING: Skin laser center of a university hospital. PATIENTS: Twenty-three Thai women with acquired bilateral nevus of Ota-like macules. INTERVENTIONS: Patients were treated using a 1064-nm Q-switched Nd:YAG laser at an average fluence of 7.0 J/cm(2) using a 3-mm spot size. The same laser fluence was used on both sides of the face in individual patients. One randomly selected face side of each patient was cooled using a cold air cooling device during and 30 seconds before and after laser irradiation, and the other side was irradiated without cooling. MAIN OUTCOME MEASURES: Occurrence of PIH was objectively evaluated by measuring the melanin index using a spectrometer, and it was subjectively assessed by 2 nontreating physicians before treatment and once weekly for 4 weeks. RESULTS: Of the 21 patients who completed the study, 13 (62%) and 5 (24%) developed PIH on the cooled and uncooled sides, respectively. One patient (5%) had PIH on both the cooled and uncooled sides, and 2 (10%) did not experience PIH. The cooled sides were significantly more likely to become hyperpigmented after laser irradiation than the uncooled sides (relative risk, 2.6; 95% confidence interval, 1.13-6.00; P = .03). The clinical evaluation corresponded to the spectrometer reading. CONCLUSION: Epidermal cooling with cold air is associated with an increased risk of PIH after Q-switched Nd:YAG laser treatment. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00287001.

Analysis of 602 Chinese cases of nevus of Ota and the treatment results treated by Q-switched alexandrite laser.

BACKGROUND: Nevus of Ota is a congenital or acquired pigmentary disorder of the skin and mucous membranes, which are areas innervated by the first and second branches of the trigeminal nerve. Nevus of Ota is very common in Asia. Nevus of Ota was effectively treated with Q-switched alexandrite (755 nm) laser, but no detailed report existed on many Chinese cases treated with Q-switched alexandrite laser. OBJECTIVE: The objective was to gauge clinical and treatment data and material statistics for 602 cases of nevus of Ota and analyze its pathogenic mechanism and therapeutic results. METHODS: A total of 602 cases of clinical data on nevus of Ota were collected by means of clinical registration, photo verification, and telephone inquiry or correspondence. CONCLUSIONS: There are some differences in sex, age, and local regions in nevus of Ota. Nevus of Ota can combine with other diseases. The treatment of Nevus of Ota by a Q-switched alexandrite laser is safe and effective. Additional treatment will achieve good results. The results correlate to the eyelids and Tanino's classification.