Evaluation of the safety and efficacy of the dual wavelength picosecond laser for the treatment of benign pigmented lesions in Asians: PICOSECOND LASER FOR BENIGN PIGMENTED LESIONS IN ASIANS

Efficacy and safety of a novel 785 nm picosecond neodymium-doped yttrium aluminum garnet laser for the treatment of facial benign pigmented lesions in Asian skin: a pilot study

BACKGROUND AND OBJECTIVES

Benign pigmented lesions and a general uneven tone in people with skin of color are growing issues that have been presented to dermatologists. To the best of our knowledge, this is the first controlled study to examine the efficacy and safety of using the newly introduced 785 nm neodymium-doped yttrium aluminum garnet (Nd:YAG) picosecond laser to treat facial benign pigmented lesions in Asian patients with diffractive lens array.

MATERIALS AND METHODS

A 785 nm Nd:YAG picosecond laser was used to treat 15 healthy female volunteers older than 18 years who had Fitzpatrick skin types II-IV and facial benign pigmented lesions. Each volunteer received five weekly treatments in dual modes. The clinical improvement was assessed by independent investigators and by objectively measuring the melanin index.

RESULTS

After the treatment, the melanin and erythema indices decreased, and the pigmented lesions showed clinical improvements. No serious adverse effects were observed during the study period.

CONCLUSIONS

A 785 nm Nd:YAG picosecond laser may be safe and effective in treating facial benign pigmented lesions in Asian skin.

Focal point technology: Controlling treatment depth and pattern of skin injury by a novel highly focused laser

BACKGROUND

Selective photothermolysis has limitations in efficacy and safety for dermal targets. We describe a novel concept using scanned focused laser microbeams for precise control of dermal depth and pattern of injury, using a 1550 nm laser that generates an array of conical thermal zones while minimizing injury to the epidermis.

OBJECTIVE

To characterize the conical thermal zones in vivo and determine safe starting parameters to transition to a second phase to explore potential clinical indications.

METHODS

A focused toroidal (ring) laser beam was delivered through a cold sapphire window, sparing epidermal injury in a central zone. Pulse energy, lesion depth, density, and energy delivery were titrated in ex vivo human skin and subsequently on the backs of 21 human subjects.

RESULTS

Histology showed microscale patterns of thermal injury, which varied predictably with laser parameters. Time-course healing through histology and skin surface imaging demonstrated the ability of the device to deliver high energies without sequelae.

LIMITATIONS

Clinical data are currently being collected to further explore the safety and efficacy of the device.

CONCLUSION

The 1550 nm laser with focal point technology enables precise control of lesion depth while simultaneously sparing a large portion of the epidermis, lowering the risk of adverse effects.

Efficacy and Safety of Low-Fluence 730-nm Picosecond Laser in the Treatment of Melasma in Chinese Patients

BACKGROUND

The 730-nm picosecond laser has shown promise in treating various benign pigmentary conditions, and it is yet to be determined whether it is effective and safe for melasma.

OBJECTIVE

The aim of this study was to investigate the potential benefits and risks of using the 730-nm picosecond laser to remove melasma.

MATERIALS AND METHODS

This is a retrospective review of all patients who presented to the clinic between April 2021 and April 2022 for the treatment of melasma with 730-nm picosecond laser alone. The efficacy of the laser was assessed based on the Melasma Area and Severity Index (MASI) score using high-resolution photographs evaluated by blinded dermatologists.

RESULTS

A total of 25 Chinese with Fitzpatrick skin Type II to IV were included. Patients were treated for an average of 3.56 ± 0.77 treatment sessions. The mean MASI scores decreased by 33.7% from 11.38 ± 6.60 to 7.55 ± 6.08 at an average of 8.48 ± 2.16 weeks of follow-up (p < .001). Among the patients, 1 experienced a 79% decrease, 6 had a decrease ranging from 51% to 75%, 10 had a decrease ranging from 26% to 50%, 5 had a decrease of less than 25%, and 3 experienced no changes in MASI scores. No hyper/hypopigmentation was observed.

CONCLUSION

Low-fluence 730-nm picosecond laser is an effective and safe modality for the treatment of melasma in Chinese patients.

Evaluation of a Novel Dermal Cooling System for the Treatment of Benign Pigmented Lesions in Asians

OBJECTIVE

Our study aimed to evaluate the efficacy of this novel dermal cooling system (DCS) in reducing pigmentation in benign pigmented lesions in Asian patients and its potential side effects.

METHODS

It was a prospective open-label single-center study. Asian patients, with the presence of benign pigmented lesions mainly including lentigines, melasma, nevus spilus, ephelides, café au lait, and seborrheic keratosis were recruited for a novel DCS. The DCS provided localized cooling of the epidermal layer below freezing but was less intense than cryotherapy. Each patient received DCS at Week 0 and repeated at 4-week intervals up to 10 sessions. Global aesthetic improvement scores (GAIS) by blinded physicians and subjects were recorded at 2, 6, and 12 months posttreatment follow-up.

RESULTS

Eighty-one patients were recruited with a total of 305 sessions performed and 1716 lesion sites treated. At 2-month posttreatment, 76.5% and 58.6% treatment sites showed obvious to marked improvement respectively and the improvement sustained at 6 and 12 months. Only minor adverse events were reported. Erythema and edema were the most commonly anticipated effects immediately after treatment. The pain was minimal. Postinflammatory hyperpigmentation was only reported in 2.2% (38/1716) treated sites.

CONCLUSION

To our knowledge, this study was the first study to demonstrate that this novel DCS was an effective, safe, and well-tolerated treatment for benign pigmented lesions in Asians.

Efficacy and Safety of Solid-state Dual-wavelength Lasers for the Treatment of Moderate-to-severe Inflammatory Acne in Asian Populations

Background

Standard treatments for moderate-to-severe acne often require oral medications but are not long-lasting or free from side effects. We aimed to evaluate the efficacy and safety of a solid-state dual-wavelength laser for moderate-to-severe inflammatory acne in an Asian population.

Methods

Forty individuals with moderate-to-severe acne received nightly topical retinoids and two to three weekly treatments with a 1319-nm laser followed by a 589-nm laser (five sessions in total). Patients were evaluated at pretreatment baseline, at monthly intervals, and at 1 month after the last laser for pain, seborrhea, global aesthetic improvements, and satisfaction, using standardized digital photography and global assessment scales. Fifteen patients had an additional evaluation 3 months after the fifth session.

Results

At 1 month, all patients (n = 40) had improved inflammatory acne counts, with 72.5% having greater than 75% reduction in acne count, 7.5% having 51%-75% reduction, 17.5% having 26%-50% reduction and 2.5% having less than 25% reduction. Moreover, GAS evaluations showed that 62.5% of patients improved to almost clear and 37.5% to mild acne (P = 0.0478), while improvements were sustained in patients with 3-month follow-ups. Erythema (n = 29) improved with 65.5% of affected patients having greater than 75% reduction. Patients (n = 17) with pigmentation experienced lightening, with 52.9% of affected patients having a greater than 75% reduction. With low pain scores (mean 3.68 of 10, median 4 of 10), the treatment was well-tolerated. All patients (n = 40) reported acne improvements with 95% having much improved or very much improved, and 95% either satisfied or very satisfied.

Conclusions

Dual-wavelength lasers effectively and safely treat moderate-to-severe inflammatory acne with high patient satisfaction. It is ideal for patients who refuse or are contraindicated to oral medications, and patients with acne-associated pigmentation, erythema and seborrhea.

Picosecond lasers in cosmetic dermatology: where are we now? An overview of types and indications

Q-switched lasers have undeniably revolutionized the field of laser dermatology since four decades ago. Just as the first-generation laser emits its photonic signal in a few nanoseconds, the picosecond laser delivers pulse widths of at least ten times shorter. These devices offer a powerful tool for treating a wide range of skin conditions with a minimal downtime for visible improvement. For the current study, a literature research was performed on the dermatological applications of picosecond laser. The literature searched on this topic between 1999 and 2023 accessible through various platforms produce a result of 62 articles. The included studies have discussed the application of picosecond laser technology in tattoo removal, treatment of epidermal and dermal pigmentation, and collagen remodeling. After sifting the data from the articles into tables, the results were discussed in detail. The study shows a lot of evidence towards the efficacy of picosecond laser, yet it draws attention to its downsides.

Use of Picosecond Laser for Melasma Treatment: A Narrative Review

Background: Melasma results from the imbalance of the mechanisms that regulate skin pigmentation, causing the appearance of hyperpigmented patches. Treatment includes topical and oral agents, chemical peelings, microneedling, and laser therapy. The picosecond laser was developed to minimize pain and skin discoloration, which can sometimes be associated with laser treatments. It emits short pulses of energy that last from 300 to 500 picoseconds, leading to a more significant fragmentation of melanin, with miniminal risk of scarring and thermal lesions in the surrounding skin. Objective: The authors aimed to review the use of picosecond laser in the treatment of melasma and further provide an overview of the other current available options. Conclusions: While the use of picosecond laser for the treatment of melasma has yielded good results, further studies with longer follow-up periods and a higher number of patients are needed.

Comparison of the efficacy and safety of a 730 nm picosecond titanium sapphire laser and a 755 nm picosecond alexandrite laser for the treatment of freckles in Asian patients: A two-center randomized, split-face, controlled trial

OBJECTIVE

The 730 nm picosecond titanium sapphire laser is a novel laser that shows promising results in treating freckles. This study aimed to further investigate the efficacy and safety of the 730 nm picosecond titanium sapphire laser for treating freckles in Asian patients compared with those of the 755 nm picosecond alexandrite laser.

METHODS

Each face of 86 participants was split into two parts and randomly assigned either one session of 730 or 755 nm picosecond-laser treatment each. Efficacy and safety were determined based on blinded visual evaluations and self-reports at each follow-up visit.

RESULTS

The treatment outcomes of the 730 nm picosecond laser for the treatment of freckles were comparable to those of the 755 nm picosecond laser, with 68.99 ± 7.42% and 69.27 ± 7.75% clearance, respectively (p > 0.05). Participants achieved similar Global Aesthetic Improvement Scale scores (4.04 ± 0.31 vs. 4.02 ± 0.30, respectively [p > 0.05]). Additionally, the 730 nm picosecond laser was perceived to be less painful than the 755 nm picosecond laser (4.69 ± 1.63 vs. 5.65 ± 1.80 nm, p < 0.0001).

CONCLUSION

The 730 nm picosecond laser is safe and effective for the treatment of freckles in Asian patients. Besides, the 730 nm picosecond laser is less painful than the 755 nm picosecond laser.

Treatment of Periorbital Vascularity, Erythema, and Hyperpigmentation

Periorbital hyperpigmentation (POH) is a common aesthetic concern that impacts patients' emotional well-being and quality of life. POH can be difficult to manage as the etiology is often multifactorial or difficult to elucidate. An understanding of different contributing factors and ability to classify hyperpigmentation can aid in the management of POH. Classification of POH is divided into pigmented, vascular, structural, and mixed subtypes. A wide array of treatment options has been proposed belying the challenges inherent to improving POH. Modalities vary from topical therapies, chemical peels, dermal fillers, and lasers, to surgical intervention. Because POH can be multifactorial, successful management of POH will depend on elucidating the etiology and often requires a combination of therapies.

Laser treatment for Cafe-au-lait Macules: a systematic review and meta-analysis

Nowadays, laser is the mainstay treatment for cafe-au-lait macules (CALMs), but no systematic review has been published to demonstrate the overall efficacy and it's still controversial which type of laser is optimal. Thus, we conduct the meta-analysis to evaluate the effectiveness and side effects of various types of lasers in treating CALMs. Original articles reporting the efficacy and side effects for CALMs in laser treatment were identified in PubMed, EMBASE, and Web of Science from 1983 to April 11, 2023. Using R software and the 'meta' package, meta-analysis was conducted for clearance and recurrence for evaluation of efficacy. And the occurrence of hypopigmentation and hyperpigmentation rate was pooled for safety evaluation. We used RoB2 and ROBINS-I tools to assess the risks of bias in RCT studies and non-RCT studies, respectively. The Grading of Recommendations, Assessment, Development and Evaluation system was used to assess the quality of the evidence. Nineteen studies involving 991 patients were included, which had a very low to moderate quality of evidence. The pooled 75% clearance rate was 43.3% (95% CI 31.8-54.7%, I² = 96%), 50% clearance rate was 75% (95% CI 62.2-85.9%, I² = 89%) and the recurrence rate was 13% (95% CI 3.2-26.5%, I² = 88%). The pooled hypopigmentation and hyperpigmentation rates were 1.2% (95% CI 0.3-2.1%, I² = 0%) and 1.2% (95% CI 0.3-2%, I² = 0%), respectively. Subgroup analysis revealed that QS-1064-nm Nd:YAG laser treatment not only achieved more than 75% clearance rate in 50.9% of patients (95% CI 26.9-74.4%, I² = 90%) but also resulted in the lowest hypopigmentation and hyperpigmentation rate of 0.5% (95% CI 0.0-2.5%, I² = 26%) and 0.4% (95% CI 0.0-2.5%, I² = 0%). To draw a conclusion, the laser treatment could reach an overall clearance rate of 50% for 75% of the patients with CALMs, for 43.3% of the patients, the clearance rate could reach 75%. When looking at different wavelength subgroups, QS-1064-nm Nd:YAG laser exhibited the best treatment capability. Laser of all the wavelength subgroups presented acceptable safety regarding of the low occurrence of side effects, namely, hypopigmentation and hyperpigmentation.

Video education improves patients' knowledge and satisfaction in treatment of solar lentigines with picosecond 755-nm alexandrite laser: A retrospective study

Background

Picosecond lasers are widely used in dermatologic and cosmetic practice. In clinical practice, informed consent for laser treatments is critical to ensure patients' understanding of health information.

Objectives

To evaluate whether video-based informed consent improves patient comprehension and satisfaction.

Methods

The study was performed from August 1 to November 30, 2022. Solar lentigines patients who fulfilled the inclusion criteria were included. Before October 1, 2022, traditional informed consent methods were performed. In the subsequent 2 months, a video-based informed consent was used as an adjunct to traditional consenting methods. Finally, patient comprehension of relevant knowledge about laser treatment and client satisfaction were assessed.

Results

A total of 106 patients were included. The mean number of correct answers in the comprehension assessment in the video-based informed consent group was significantly higher than that in the traditional informed consent group (4.4 ± 1.2 vs. 3.4 ± 1.1, p < 0.001). Compared to the traditional informed consent group, more correct answers in the video-based informed consent group were provided by older patients (3.9 ± 1.2 vs. 2.9 ± 1.1, p = 0.004) and patients with lower education levels (4.1 ± 1.1 vs. 3.0 ± 1.2, p < 0.001). The mean satisfaction score in the video-based informed consent group was significantly higher than that in the traditional informed consent (27.8 ± 5.7 vs. 24.3 ± 6.2, p = 0.003).

Conclusion

Video-based informed consent helps patients learn clinical literacy more effectively and improves patient satisfaction, especially in those with lower education levels and older ages.

Comparison of the efficacy and safety of picosecond Nd:YAG laser (1,064 nm), picosecond alexandrite laser (755 nm) and 2% hydroquinone cream in the treatment of melasma: A randomized, controlled, assessor-blinded trial

Background

Increasing numbers of studies demonstrated that picosecond lasers (Picos) were effective and safe for melasma. However, A limited number of randomized controlled trials (RCTs) regarding Picos contribute to a modest level of evidence. Topical hydroquinone (HQ) remains to be the first-line therapy.

Objective

To compare the efficacy and safety of non-fractional picosecond Nd:YAG laser (PSNYL), non-fractional picosecond alexandrite laser (PSAL), and 2% HQ cream in the treatment of melasma.

Method

Sixty melasma patients with Fitzpatrick skin types (FST) III-IV were randomly assigned to the PSNY, PSAL, and HQ groups at a 1:1:1 ratio. Patients in PSNYL and PSAL groups received 3 laser sessions at 4-week intervals. The 2% HQ cream was applied twice daily for 12 weeks in patients of the HQ group. The primary outcome, the melasma area and severity index (MASI) score, was evaluated at weeks 0, 4, 8, 12, 16, 20, and 24. The patient assessment score by quartile rating scale was rated at weeks 12, 16, 20, and 24.

Results

Fifty-nine (98.3%) subjects were included in the analysis. Each group showed significant change from baseline in MASI scores from week 4 to week 24. The MASI score in the PSNYL group showed the greatest reduction compared to the PSAL group (p = 0.016) and HQ group (p = 0.018). The PSAL group demonstrated comparable MASI improvement as the HQ group (p = 0.998). The PSNYL group had the highest patient assessment score, followed by the PSAL group and then the HQ group, although only the differences between PSNYL and HQ groups at weeks 12 and 16 were significant. Four patients (6.8%) experienced recurrence. Other unanticipated events were transient and subsided after 1 week to 6 months.

Conclusion

The efficacy of non-fractional PSNYL was superior to that of non-fractional PSAL, which was not inferior to 2% HQ, thus non-fractional Picos providing an alternative for melasma patients with FSTs III-IV. The safety profiles of PSNYL, PSAL, and 2% HQ cream were similar.

Clinical Trial Registration

https://www.chictr.org.cn/showprojen.aspx?proj=130994, ChiCTR2100050089.

Prospective Study of 532-nm Picosecond Laser for the Treatment of Pigmented Lesions of the Face and Dorsal Hands

BACKGROUND

Pigmented lesions from chronic UV photoaging are extremely common on the face and hands.

OBJECTIVE

To evaluate the safety and efficacy of a 532-nm picosecond laser for these types of pigmented lesions.

METHODS

This was a single-center, prospective, open-label clinical trial. Eligible subjects with pigmentation on the face and hands received 3 monthly treatments, with 1 month (1M) and 3 months (3M) follow-up. Change in investigator-graded overall facial and per lesion pigmentation and subject-graded satisfaction and pigmentation improvement was evaluated by a 5-point scale. Immediate skin response and adverse events (AEs) were evaluated post-treatment. The melanin index was measured using a mexameter. Randomized before and after photographs were graded by 3 blinded physicians for degree of pigmentation improvement.

RESULTS

Twenty-five subjects (22F/3M) with Fitzpatrick skin types I-III were enrolled, with 23 subjects completing. Treatments used a 532 nm wavelength, 800 ps pulse duration, 4-6mm spot size, and 0.1 to 0.6J/cm2 fluence. Good-to-excellent clearance at 1M/3M was demonstrated in ≥95% of lesions (n = 116). Only mild treatment-related pain was reported, with transient post-treatment AEs (mean downtime of 2.1 ± 2.0 days) and no serious treatment-related AEs. Subject satisfaction (satisfied or very satisfied) was 95% at 1M and 91% at 3M.

CONCLUSION

Treatment with a 532-nm picosecond laser is safe and highly effective for the treatment of the pigmented lesions of the face and dorsal hands.

Efficacy of a laser with a pulse duration of 300 ps in skin rejuvenation and treatment of pigmentation disorders in Asians: a series of four cases

The photothermal effect of lasers is minimized and the photoacoustic effect is maximized as the pulse duration is shortened. Therefore, picosecond lasers with a short pulse and high peak power can be used to effectively treat various pigment disorders by reducing tissue damage. The first picosecond lasers were used for tattoo removal; they are also widely used for pigment treatment because of their reduced side effects compared with nanosecond lasers. Recently, picosecond lasers have been shown to be effective in the treatment of various skin conditions such as acne scars and large pores. There are many studies on picosecond lasers; however, there are no studies on a laser with a pulse duration of 300 ps. This report describes the use of a 300 ps Nd:YAG laser for treating pigment disorders and for skin rejuvenation in four Asians, with no side effects. Determining the clinical significance of the 300 ps pulse duration through comparative studies with various picosecond lasers is needed.

Treatment of facial and non-facial lentigines with a 730 nm picosecond titanium: Sapphire laser is safe and effective

Objective

A 730 nm picosecond‐domain laser was developed to improve the clearance of pigmented lesion and reduce adverse events. This study assessed the safety and efficacy of this system for the clearance of lentigines and explores how the short picosecond pulses interact with tissue via histology.

Study Design and Methods

Twenty subjects with Fitzpatrick skin types II–IV were enrolled in this prospective, IRB‐approved study. Four treatments were administered using a 730 nm picosecond‐domain laser. Pre‐ and posttreatment photos were assessed by blinded reviewers at 4‐ and 12‐week follow‐up visits, using a 5‐point clearance scale. Subject satisfaction was measured using a 5‐point scale. Investigator Global Improvement Score (IGIS) was performed at the 4‐ and 12‐week follow‐up visits, using an 11‐point clearance scale. Subject pain level was measured using an 11‐point scale (no pain [0], extreme pain [10]). Histology of 730 and 532 nm picosecond pulses was compared with 755 and 532 nm nanosecond pulses.

Results

Sixteen subjects with a total of 118 discontinuous treatment areas, each comprised of 1–20 lesions, completed all study visits. Thirty body regions were studied, including arms (6), hands (16), scalp (1), forehead (2), face (3), and back (2). Spot sizes ranging from 2 to 5 mm diameters were used with fluences ranging from 0.8 to 4.0 J/cm². Mean pain score was 3.6 of 10 for all four treatments. Ninety‐nine percent of randomly paired 4‐week posttreatment images and 100% of 12‐week posttreatment images were correctly identified from their respective baseline images by three blinded reviewers. Mean IGIS demonstrated scores of 6.7 and 7.0 at 4‐ and 12‐week follow‐up visits, respectively. At the 4‐ and 12‐week follow‐up visits, 76% and 73% of subjects, respectively, were satisfied to highly satisfied. The mean clearance score for all 118 treatment areas was 3 of 4 in follow‐up visits. At 12‐week follow‐up, 36% of 118 treatment areas had a clearance score of 4, and 38% had a clearance score of 3. Post treatment, there was typical erythema, edema, dryness, crusting, and itching but negligible purpura, no pinpoint bleeding, blistering or scarring, and no significant hyperpigmentation or hypopigmentation. Histology showed diffuse, focal epidermal vacuolization ~5–10 µm in diameter and mild extravasation of erythrocytes with 730 nm picosecond pulses, while diffuse epidermal vacuolization was observed with coalescence of vacuoles (~20–100 µm), junctional clefting and mild extravasation of erythrocytes with 755 nm nanosecond pulses. Picosecond pulses of the wavelength of 532 nm produced diffuse, focal epidermal vacuolization and larger dermal vacuoles to depths of 500 µm, while 532 nm nanosecond pulses produced diffuse epidermal vacuolization with coalescence of vacuoles and marked dermal hemorrhage.

Conclusion

This study demonstrated the potential of a new 730 nm picosecond‐domain laser for the clearance of lentigines. The results showed good clearance with no adverse events and good subject satisfaction in patients with skin type II–III. Additional studies need to be conducted on darker skin types. The histopathologic findings demonstrate that the picosecond 730 nm laser produces excellent selectivity for pigment with minimal disruption of the dermal–epidermal junction and may therefore reduce healing times and the risk of adverse events.

Incident Fluence Analysis for 755-nm Picosecond Laser Treatment of Pigmented Skin Lesions Based on Threshold Fluences for Melanosome Disruption

Background and Objectives

In this study, the threshold fluences for disrupting the melanosomes for pigmented skin lesion treatment were determined using a 755‐nm picosecond laser for clinical use. Based on the melanosome disruption thresholds, incident fluences corresponding to the target lesion depths were evaluated in silico for different laser spot sizes.

Study Design/Materials and Methods

Melanosome samples were isolated from porcine eyes as alternative samples for human cutaneous melanosomes. The isolated melanosomes were exposed to 755‐nm picosecond laser pulses to measure the mean particle sizes by dynamic light scattering and confirm their disruption by scanning electron microscopy. The threshold fluences were statistically determined from the relationships between the irradiated fluences and the mean particle sizes. Incident fluences of picosecond laser pulses for the disruption of melanosomes located at different depths in skin tissue were calculated through a light transport simulation using the obtained thresholds.

Results

The threshold fluences of 550‐ and 750‐picosecond laser pulses were determined to be 2.19 and 2.49 J/cm², respectively. The numerical simulation indicated that appropriate incident fluences of picosecond laser pulses differ depending on the depth distribution of the melanosomes in the skin tissue, and large spot sizes are desirable for disrupting the melanosomes more deeply located within the skin tissue.

Conclusion

The threshold fluences of picosecond laser pulses for melanosome disruption were determined. The incident fluence analysis based on the thresholds for melanosome disruption provides valuable information for the selection of irradiation endpoints for picosecond laser treatment of pigmented skin lesions. Lasers Surg. Med. © 2021 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals LLC

Treatment of benign hyperpigmentations and pigmented scars by 755 alexandrite laser comparing the Single Pass versus MultiPass (MoveoPL) emission in skin types I-IV

Lasers are effective treatments for benign hyperpigmentations but may be difficult especially in darker skin type. In this randomized split-face controlled study on benign hyperpigmentations and pigmented scars, we compare the standard Single Pass (SP) emission with the MultiPass emission (MoveoPL) 755 alexandrite laser. Patients, skin types I-IV, with solar lentigines and ephelides of the face, chest, and hands and patients with pigmented scars of the legs, underwent laser treatment, by treating one side of the body or half scar using the SP and the other side using MoveoPL. Improvements according to a grading score system, side effects, and patient satisfaction were recorded. About 63 patients were enrolled. An overall improvement of benign hyperpigmentations and pigmented scars was recorded, with a grading score (±SD) of 2.8 ± 0.8 for SP and 3.6 ± 0.5 for MoveoPL (range, 0-4). SP emission showed best results in skin types I-II whereas MotusPL obtained successfully results in all the phototypes analyzed (types I-IV). Patients preferred MoveoPL as it was associated with fewer side effects. Both standard SP and MoveoPL emission are effective and safe. MoveoPL showed a higher efficacy and safety profile for the treatment of hyperpigmentations.

Fractional 1064 nm Picosecond Laser in Treatment of Melasma and Skin Rejuvenation in Asians, A Prospective Study

BACKGROUND AND OBJECTIVES

Facial melasma is a disfiguring pigmentation and occurs frequently with aging skin. Topical treatment alone was often suboptimal. A recent study showed that fractional picosecond laser has promising result in benign pigmentary lesions. This study aims to investigate the efficacy and safety of 1064 nm picosecond laser in treatment of facial melasma and skin rejuvenation in Asian skin.

STUDY DESIGN/MATERIALS AND METHODS

Patients of Asian descent seeking treatment for facial melasma and skin rejuvenation were screened and recruited. Each patient received up to nine laser treatments at 4-6 weeks intervals with a fractionated nonablative 1064 nm picosecond laser. Baseline and posttreatment modified Melasma Area Severity Index (mMASI) and Global Aesthetic Improvement Scale (IGAS) were assessed by blinded investigators based on the clinical photographs. Subject overall satisfaction was assessed by the questionnaires after treatment. All adverse events were documented.

RESULTS

Twenty patients were recruited with a median age of 52.7 ± 8.2 years. Three subjects had Fitzpatrick skin type III and 17 had skin type IV. All subjects received nine laser sessions. Over 70% of patients were satisfied with the treatment outcomes. There was a statistically significant improvement in mMASI which reduced from 10.8 at baseline to 2.7 and 3.6 at 6 and 12 weeks post-treatment, respectively (both P < 0.01). For skin rejuvenation, 70% reported at least a moderate improvement at 6 weeks of post-treatment. No major side-effect was reported. Erythema was the most frequent transient response, while some reported edema (1.1%). Both resolved spontaneously. None reported hypo- or hyperpigmentation after treatment. The overall mean pain scare (VAS) was 1.92.

CONCLUSION

Fractionated non-ablative 1064 nm picosecond laser was effective in treatment of melasma and skin rejuvenation. It was also safe and well tolerated. Importantly, there was no hypo or hyperpigmentation reported. Lasers Surg. Med. 00:00-00, 2021. © 2021 Wiley Periodicals LLC.

Treatment of pigmentary disorders using picosecond laser in Asian patients: A meta-analysis and systematic review

There were many studies evaluating the effect of picosecond (PS) lasers, but no meta-analysis examined the effects of PS laser in the treatment of pigmentary disorders in Asians. The aim of this article was to review the before-after effect of PS laser in Asians for the treatment of pigmentary disorders. PubMed, Embase, and Cochrane library were searched for articles published up to May 2020. The evaluations were summarized into a 4-point scale that ranged from <25% (poor), 25%-50% (fair), 50%-75% (good), and 75%-100% (excellent). Effect sizes (ESs) were calculated according to laser wavelengths and lesion types. There were two randomized controlled trials, three single-arm trials, and three case series, with 200 patients. At 3 months after treatment, of all included patients, 3% (95%CI: 1%-6%) were evaluated as poor or worse, 9% (95%CI: 2%-21%) as fair, 29% (95%CI: 12%-50%) as good, and 56% (95%CI: 28%-83%) as excellent. The 532 and 1064, and 755 nm PS lasers had similar ESs across all four response groups. This meta-analysis suggested that 56% of Asian patients who underwent PS laser for the treatment of pigmentary disorders were evaluated as "excellent" about the pigment clearance by a dermatologist at least 3 months after 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.

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/cm² (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/cm² (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.

Comparative Effectiveness of 755-nm Picosecond Laser, 755- and 532-nm Nanosecond Lasers for Treatment of Café-au-Lait Macules (CALMs): A Randomized, Split-Lesion Clinical Trial

BACKGROUND AND OBJECTIVES

Many types of lasers have been used to treat café-au-lait macules (CALMs) since the introduction of the selective photothermolysis theory. However, the efficacy and safety of picosecond lasers, compared with those of nanosecond lasers, have not been researched. To compare the efficacy and safety of 755 nm picosecond laser (PS-755 nm), Q-switched (QS) Alexandrite 755 nm nanosecond laser (QS-755 nm), and QS Nd:YAG 532 nm nanosecond laser (QS-532 nm) for treating CALMs.

STUDY DESIGN/MATERIALS AND METHODS

Forty-one patients received several treatments at 3-month intervals. Lesions were divided into two or three approximately equal parts, which were randomly treated with PS-755 nm, QS-755 nm, and QS-532 nm. The safety and efficacy of three lasers were determined based on blinded visual assessments and self-reports of patients three months after the comparative trial.

RESULTS

Visual assessment 3 months after the comparative trial revealed that there was no statistically significant difference among the sites treated by QS-755 nm (2.84 ± 1.11), QS-532 nm (2.63 ± 1.06), and PS-755 nm (2.74 ± 1.05) lasers. Five (26.32%) of 19 patients showed lesion recurrence. Adverse effects included acneiform miliaris, hypopigmentation, and hyperpigmentation, which were resolved within 12 months. Five (26.32%) of 19 patients who showed lesion recurrence 1-5 months after laser treatment had lightened or cleared at least 50% of the lesion. 46.67% of patients were satisfied or very satisfied with the outcome of the overall treatment.

CONCLUSIONS

PS-755 nm, QS-755 nm, and QS-532 nm laser treatments were equally effective in treating and improving CALMs. PS-755 nm caused fewer adverse effects. Individuals can react differently to different types of lasers. Patch tests should be conducted before the treatment. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Safety and Efficacy of a Novel 730 nm Picosecond Titanium Sapphire Laser for the Treatment of Benign Pigmented Lesions

BACKGROUND AND OBJECTIVES

Picosecond lasers in dermatology were originally focused on optimizing the removal of unwanted tattoos. Subsequent advances in this technology have expanded its clinical indications to include treatment of benign pigmented lesions, photodamage, melasma, and scar revision. In this retrospective review, we evaluate a novel 730 nm picosecond titanium sapphire laser in treating benign pigmented lesions.

STUDY DESIGN/MATERIALS AND METHODS

This is a retrospective review of all patients who presented to our institution between December 2019 and March 2020 for treatment of their benign pigmented lesions with a 730 nm picosecond titanium sapphire laser. All Fitzpatrick skin types (I-VI) were included. Absolute and relative evaluations were conducted by two blinded board-certified dermatologists using high-resolution photographic images.

RESULTS

Twenty-two of 64 patients satisfied inclusion and exclusion criteria. Patients received 1.1 ± 0.3 treatment sessions. The absolute average pigmentation score prior to treatment was 2.04 ± 0.7 versus 1.39 ± 0.6 after treatment (P < 0.05). Improvement in pigmentation was observed in 86% of the patients, while 3% had no improvement and 11% had worsening of pigmentation. No other adverse events were observed. Downtime consisted of 1-2 days of mild edema and erythema followed by 3-5 days of mild pigment darkening and superficial crust.

CONCLUSION

The novel 730 nm picosecond titanium sapphire laser is a safe and effective treatment for benign pigmented lesions. Future prospective randomized control studies would be beneficial to further clarify its role in the treatment of benign pigmentation. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Effective removal of solar lentigines by combination of pre- And post-fluorescent light energy treatment with picosecond laser treatment

We present a novel treatment for removal of SL that is efficient and enables removal or lesions not immediately visible. Kleresca® FLE technology combined with picosecond laser treatment removes SL lesions and improves skin quality and appearance.

A Systematic Review of Picosecond Laser in Dermatology: Evidence and Recommendations

BACKGROUND AND OBJECTIVES

The use of picosecond laser in dermatology was originally focused on optimizing the removal of unwanted tattoos. Subsequent advances in this technology have broadened its clinical indications to include treatment of benign pigmented lesions, photodamage, melasma, and scar revision. In this systematic review, evidence-based recommendations are developed for the use of picosecond laser in dermatology.

STUDY DESIGN/MATERIALS AND METHODS

A comprehensive search of the English language literature was performed up to and including November 2019. Relevant citations were individually evaluated, synthesized, and categorized based on the Level of Evidence. With the addition of the authors' combined clinical experience, clinical recommendations were developed.

RESULTS

After application of inclusion and exclusion criteria, a total of 77 unique studies were evaluated. Treatment of benign pigmented lesions was associated with level I-IV evidence; rejuvenation was associated with level II evidence; melasma was associated with level II evidence; scar revision was associated with level II-III evidence; tattoo removal was associated with level I evidence.

CONCLUSION

Picosecond laser is a safe and effective treatment modality for an increasing range of dermatologic indications. Further development of this technology is warranted. Lasers Surg. Med. © 2020 Wiley Periodicals, Inc.

In vivo reflectance confocal microscopy for evaluating common facial hyperpigmentation

BACKGROUND

In clinical settings, atypical facial hyperpigmentation such as nevus of Ota, acquired bilateral nevus of Ota-like macules (ABNOM), melasma, and café-au-lait spots are often missed and misdiagnosed. Summarizing in vivo reflectance confocal microscopy (RCM) features of the hyperpigmentation is helpful in the diagnosis of ambiguous lesions.

METHODS

We recruited 196 patients referred for unequivocal facial hyperpigmentation, including 55 patients with nevus of Ota, 45 patients with ABNOM, 62 patients with melasma, and 34 patients with café-au-lait spots. The RCM images were evaluated at the epidermis, the dermis-epidermis junction (DEJ), and the upper papillary dermis from both hyperpigmented patches and normal skin.

RESULTS

In the superficial and middle dermis, 41 of 55 patients (74.5%) with nevus of Ota were characterized by a cord-like or lumpy structure between the collagen fibers. And there was no melanin deposition detected in the dermis in 14 of 55 (25.5%) patients. In ABNOM, 37 of 45 (82.2%) patients were characterized by a cord-like or lumpy structure in the superficial dermis and 8 of 45 patients (17.8%) was no melanin deposition detected in the dermis. The epidermis was no difference between nevus of Ota, ABNOM, and the normal skin. Melasma was detected increased cobblestone pattern in the epidermis of all patients, branching architecture in 21 of 62 patients (33.9%), and focally aggregated round to triangular cells in the upper dermis of 18 of 62 patients (29.0%). In all patients with afé-au-lait spots, increased cobblestone pattern in the epidermis and regular and increased density of ringed pattern in the DEJ were visualized.

CONCLUSIONS

Our findings indicate that RCM may be useful in the auxiliary diagnosis of nevus of Ota, ABNOM, melasma, and café-au-lait spots.

Treatment of Café-Au-Lait Spots Using Q-Switched Alexandrite Laser: Analysis of Clinical Characteristics of 471 Children in Mainland China

Background and Objectives

Café‐au‐lait spots, also known as café‐au‐lait macules (CALMs), are a common pigmentary disorder. Although various laser modalities have been used to treat CALMs, the efficacy of laser treatment in children differs from that in adults. We investigated the efficacy, safety, and clinical factors of the treatment of CALMs using Q‐switched alexandrite laser (755 nm) therapy in children.

Methods

In total, 471 children with CALMs underwent Q‐switched alexandrite laser therapy at a treatment interval of 3–12 months. The safety and efficacy of the laser treatment were evaluated by reviewing clinical records and photographs before and after treatments.

Results

Of the 471 patients, 140 (29.72%) were cured completely, 124 (26.33%) showed substantial improvement, 110 (23.35%) showed improvement, and 97 (20.60%) showed no improvement after one to nine treatments. The overall treatment success rate was 79.41%, and the treatment efficacy was positively correlated with the number of laser treatments (rs = 0.26, P < 0.0001). Sex and the interval of laser treatments were also associated with significant differences in treatment outcomes (P < 0.05). No obvious adverse effects were observed. Multivariate logistic regression analysis showed that the number of treatments influenced the treatment efficacy (odds ratio, 2.130; 95% confidence interval, 1.561–2.908).

Conclusions

Q‐switched alexandrite laser (755 nm) therapy is safe and highly effective for CALMs in children, and the number of treatments affects the treatment efficacy. Lasers Surg. Med. © 2019 The Authors. Lasers in Surgery and Medicine Published by 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.