Clinical improvement of photoaging-associated facial hyperpigmentation in Korean skin with a picosecond 1064-nm neodymium-doped yttrium aluminum garnet laser

A comprehensive study of laser use in dermatology: assessing the safety, innovations, and effectiveness of laser technology for skin treatment

OBJECTIVES

The objective of this review article is to provide a general overview of the development of laser technology and its applications in dermatology. It will describe the mechanism, effectiveness, and hazardous characteristics of different laser modalities used for the treatment of skin diseases, such as disorders of pigmentation, vascular malformations, acne scarring, and photoaging.

METHODS

There was a thorough literature review through databases such as Scopus and PubMed, along with Google Scholar. Articles from 2000 to 2023 that were peer-reviewed were included. In addition to pulsed dye lasers, the search terms used in the literature review involved "laser dermatology," "skin treatment," and names of specific lasers such as carbon dioxide (CO2), Er: YAG, and Nd: YAG. Information on adverse effects, long-term effects, clinical outcomes, and patient satisfaction ratings was gathered.

RESULTS

The results show that, in the past 20 years, laser treatment has evolved significantly. Relative to historical approaches, innovations like fractional lasers have been more effective with reduced downtime. For conditions like melasma, as much as acne scars, evaluations show high levels of patient satisfaction from diverse populations. Darker skin types continue to be susceptible to adverse effects like post-inflammatory hyperpigmentation.

CONCLUSIONS

The efficacy and versatility of laser therapy have made it an anchor of dermatologic practice. Laser technology is continually evolving, with the hope of enhanced results at lower risk. To optimize benefit and minimize side effects, future research should aim to design therapy regimens specific to each skin type.

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.

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 1064-nm Nd:YAG picosecond laser using fractional micro-lens array vs. ablative fractional 2940-nm Er:YAG laser for the treatment of atrophic acne scar in Asians: a 20-week prospective, randomized, split-face, controlled pilot study

Background

The 1064-nm Nd:YAG picosecond lasers using fractional micro-lens array (P-MLA) was a promising therapy for skin resurfacing. However, no studies have compared P-MLA with ablative fractional 2940-nm Er:YAG lasers (AF-Er) in the treatment of atrophic acne scars.

Objectives

To evaluate the efficacy and safety of P-MLA and AF-Er for the treatment of atrophic acne scars.

Methods

We performed a prospective, randomized, split-face, controlled pilot study. Thirty-one Asian patients with mild to moderate atrophic acne scars underwent four consecutive sessions of randomized split-face treatment with P-MLA and AF-Fr at 4-week intervals. The efficacy of the two devices were evaluated by Echelle d'Evaluation Clinique des Cicatrices d'acne (ECCA) grading scale, Investigator's Global Assessment (IGA) score and patient's satisfaction. VISIA analysis was also performed to evaluate the pore and skin texture. Adverse events were recorded at each follow-up.

Results

The P-MLA afforded comparable clinical responses in scar appearance as AF-Er based on the investigator's assessments (ECCA percent reduction: 39.11% vs. 43.73%; IGA score: 2.97 ± 0.65 vs. 3.16 ± 0.68; P > 0.05 for both). However, the result of patient satisfaction indicated the AF-Er-treated side achieved a slightly greater improvement in scar appearance (3.97 ± 0.78 vs. 3.55 ± 0.71; P < 0.05). Overall, the two devices did not differ largely in terms of efficacy. VISIA analysis revealed similar changing patterns of the pore and skin texture between two devices. For safety profiles, no serious side effects were reported on both sides. The P-MLA showed lower pain level, shortened duration of crust shed and edema, and less occurrence of PIH (P < 0.05 for all).

Conclusion

Compared with AF-Er, P-MLA afforded comparable effect and more safety profiles in treating atrophic acne scars in Asian patients.

Clinical trial registration

ClinicalTrials.gov, identifier NCT05686603.

Microneedle fractional radiofrequency in the treatment of periorbital dark circles

BACKGROUND

Periorbital hyperpigmentation (POH) is a common disorder in the patients. Women are more upset with POH in compare to males. Several methods have been used to the POH, with different efficacy and adverse reactions.

AIM

The aim of the present study is to evaluate the efficacy of microneedle fractional radiofrequency (MRF) in treating POH.

METHODS

So, nine patients with POH and the age range of 25-57 years, were treated by microneedle fractional radiofrequency (MRF). The outcome was evaluated via biometric assessment. The colorimeter was used to assess the skin lightness. Mexameter was used for evaluated the amount of Melanin in the periorbital skin. Cutometer was used for skin elasticity assessment. The skin ultrasound imaging system was utilized to estimate the epidermis and dermis diameter and density. Furthermore, Visioface was applied to assessed the skin color and wrinkles. Also patient's satisfaction and physician's assessment were evaluated.

RESULTS

The results displayed that the periorbital skin lightness 32.38% ± 5.67 and elasticity of the R2: 40.29% ± 8.18, R5: 39.03 ± 5.38 and R7: 42.03% ± 14.16 were significantly improved after treatment (p < 0.05). Also the melanin content of the skin was decreased (49.41% ± 9.12). The skin layers were denser in the dermis and also in the epidermis (skin density: 30.21% ± 10.16 and skin thickness: 41.12% ± 13.21) (p < 0.05). The results revealed the decrease in the percent change of the skin color (30.34% ± 9.30) and wrinkle (area: 25.84% ± 6.43 and volume: 30.66% ± 8.12) (p < 0.05). Similarly, the physician and patient's assessment were confirmed the obtained outcomes.

CONCLUSION

In conclusion, the microneedle RF technique is practicable, effective and safe method for periorbital dark circles treatment.

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.

A Randomized, Prospective, Split-Face Pilot Study to Evaluate the Safety and Efficacy of 532-nm and 1,064-nm Picosecond-Domain Neodymium:Yttrium-Aluminum-Garnet Lasers Using a Diffractive Optical Element for Non-Ablative Skin Rejuvenation: Clinical and Histological Evaluation

BACKGROUND

The advent of fractionated picosecond (ps) lasers has provided an opportunity to explore new ways of creating microinjuries in the skin to induce skin rejuvenation.

OBJECTIVE

To compare the efficacy and safety of diffractive optical element (DOE)-assisted ps neodymium: yttrium-aluminum-garnet (Nd:YAG) lasers with 532-nm and 1,064-nm wavelengths (532-nm and 1,064-nm Nd:YAG P-DOE) using a novel fractional handpiece for the treatment of photoaged skin.

METHODS

An ex vivo guinea pig skin experiment was performed by evaluating the histology of the skin after 532-nm Nd:YAG P-DOE irradiation. A randomized, prospective, split-face study was performed on eight subjects with 532-nm and 1,064-nm Nd:YAG P-DOE.

RESULTS

Based on the histological evaluation using ex vivo guinea pig skin, a reasonable safety profile and the potential to generate effective skin rejuvenation was observed using the 532-nm Nd:YAG P-DOE. Results demonstrated that both 532- and 1,064-nm Nd:YAG P-DOE were similarly effective in improving skin texture and skin pores; however, 532-nm Nd:YAG P-DOE was more effective in treating dyspigmentation.

CONCLUSION

At a preliminary level, this study revealed that 532-nm and 1,064-nm ps Nd:YAG lasers using DOE fractional technology may improve photoaged skin. In conclusion, 532-nm Nd:YAG P-DOE may be especially beneficial for skin with epidermal pigmentary lesions.

Comparison of the safety and efficacy of low fluence Q-switched 1064-nm and conventional Q-Switched 755-nm lasers in the treatment of café-au-lait macules: A prospective self-controlled trial

BACKGROUND

Conventional high fluence Q-switched (HFQS) Alexandrite 755-nm are widely used in clinical café-au-lait macules (CALMs) treatment. There have been recent concerns regarding the efficacy and safety of low fluence Q-switched (LFQS) Nd: YAG 1064-nm lasers.

OBJECTIVE

To evaluate the efficacy and safety of the conventional HFQS and LFQS laser in the treatment of CALMs.

METHODS

Within 3 months, 20 patients underwent prospective self-controlled split-lesion treatments with HFQS once or twice depending on the recovery rate, and with LFQS six times biweekly. Then the more effective laser was selected for continued treatments. Efficacy outcomes were evaluated by a visual analog scale (VAS) biweekly during the comparative trail. Recovery process, side effects and recurrence were recorded during the trial and follow-up visit. Patient and physician preferences for laser selection were also recorded.

RESULTS

The average VAS scores of areas treated with HFQS and LFQS were 2.92 ± 0.86 and 2.93 ± 1.13, respectively (p > 0.05). The most significant efficacy change of LFQS was after the fourth laser treatment (VAS score: 1.82-2.37, p < 0.001). 11 lesions treated with LFQS and 7 with HFQS achieved an optimal treatment response (3.67 ≤ VAS ≤ 4). Three patients relapsed on one side (one on LFQS, two on HFQS) and five on both sides. Adverse effects included temporary hypopigmentation, hyperpigmentation, uneven pigmentation, and mottled hypopigmentation. Doctors thought 80% of patients were suitable for LFQS. 70% of patients preferred LFQS posttreatment.

CONCLUSIONS

The efficacy difference between the LFQS 1064-nm laser and HFQS 755-nm laser in treating CALMs in a 3-month comparative trial was statistically insignificant. LFQS is preferred by doctors and patients and is likely to help more patients achieve treatment efficacy than the HFQS within a short time, with fewer temporary adverse reactions, and a more even pigmentation. But it can cause mottled hypopigmentation. The LFQS had obvious lesion clearance after the fourth treatment.

A Prospective Trial of the Microneedle Fractional Radiofrequency System Application in the Treatment of Infraorbital Dark Circles

Background

Infraorbital dark circles (IDC) are commonly consulted in aesthetic practice. There is not yet a multifactorial approach to facilitating their treatment.

Objective

To investigate the safety and efficacy of the microneedle fractional radiofrequency (MRF) system for the treatment of IDC.

Methods

A prospective, split-face, evaluator-blind clinical trial was conducted to study the change in the overall appearance, color, and wrinkles in 21 female patients with mixed type IDC before and after MFR treatment.

Results

Both patients and independent evaluators found significant improvement on the global aesthetic scales after the MFR treatment, especially on periorbital wrinkles (p=0.031). Trends in decreased melanin density in the IDC area were found, but no statistical differences were established. No side effects were observed.

Conclusion

MFR is a safe and effective modality for improving mixed type IDC by correcting the structural factors.

The Low-Fluence Q-Switched Nd:YAG Laser Treatment for Melasma: A Systematic Review

Melasma is a common pigmentary disorder with a complex pathogenesis, of which the treatment is challenging. Conventional treatment often leads to inconsistent results with unexpected pigmentary side effects and high recurrence rates. Recently, the low-fluence Q-switched Nd:YAG laser (LFQSNY) has been widely used for treating melasma, especially in Asia. We reviewed literatures on the LFQSNY treatment of melasma published between 2009 and May 2022 to evaluate the efficacy and adverse events, including its combination therapy. A systematic PubMed search was conducted and a total of 42 articles were included in this study. It was hard to summarize the heterogenous studies, but LFQSNY appeared to be a generally effective and safe treatment for melasma considering the results of previous conventional therapies. However, mottled hypopigmentation has been occasionally reported to develop and persist as an adverse event of LFQSNY, which may be associated with the high accumulated laser energy. When used aggressively, even LFQSNY can induce hyperpigmentation via unwanted inflammation, especially in darker skin. Although few studies have reported considerable recurrence rates three months after treatment, unfortunately, there is a lack of the long-term follow-up results of LFQSNY in melasma. To enhance the effectiveness and reduce the adverse events, LFQSNY has been used in combination with other treatment modalities in melasma, including topical bleaching agents, oral tranexamic acid, chemical peeling, or diverse energy-based devices, which generally reduced side effects with or without significant superior efficacy compared to LFQSNY alone.

A single-blinded, randomized, controlled trial comparing efficacy between low-fluence alexandrite 755-nm picosecond laser and low-fluence neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm picosecond laser for the treatment of ultraviolet B-induced hyperpigmentation

BACKGROUND

Hyperpigmentation is a common concern of patients in dermatology clinics. Although there are many treatment options, lasers are considered a promising therapy for various hyperpigmentary conditions.

OBJECTIVES

This study aims to evaluate the efficacy of alexandrite 755-nm picosecond and neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm picosecond lasers for the treatment of ultraviolet B (UVB)-induced hyperpigmentation in Asians.

MATERIALS AND METHODS

A randomized, single-blinded study was conducted. UVB-induced hyperpigmentation was performed in three spots by narrowband UVB. After 2 weeks, these three spots were allocated into 755-treated, 1064-treated, and control sites. Patients received weekly laser treatments for five sessions. Follow-ups were scheduled at 1 and 2 months after the last session.

RESULTS

Twenty patients attended the study. Overall, 755-nm and 1064-nm picosecond lasers showed a significant improvement in the mean lightness index (L*) compared to the control site, which started at Day 49 and Day 77, respectively. The mean L* of the 755-nm-treated site was also higher than that of the 1064-nm-treated site at Day 105 (p ≤ 0.001). Initially, the mean L*, physician's visual analog scale (VAS), and patient satisfaction with the 1064-nm picosecond laser were better than those with the 755-nm picosecond laser. Nevertheless, an inversion of the mean L* and VAS was noted at Day 49, whereas the mean patient satisfaction was noted at Day 77. In the subgroup analysis, a 755-nm picosecond laser effectively treated Fitzpatrick skin types (FPTs) III and IV. However, the mean L* of the 1064-nm picosecond laser was not significantly different from that of the control for FPT4.

CONCLUSION

The alexandrite 755-nm picosecond and Nd:YAG 1064-nm picosecond lasers appear to be effective and safe modalities for treating UVB-induced hyperpigmentation. With the setting employed in this study, the outcome after the 755-nm picosecond laser treatment seemed superior to that of the 1064-nm picosecond laser treatment, especially for FPT4.

Laser-Assisted Drug Delivery of Tranexamic Acid by Picosecond Laser in Postinflammatory Hyperpigmentation: A Split-Area Double Blind Randomized Prospective Study

Background: Tranexamic acid has been reported to benefit the treatment of postinflammatory hyperpigmentation (PIH). Laser-assisted drug delivery (LADD) could facilitate the efficacy of topically applied drugs into the dermis. This split-area randomized prospective study aims to assess whether early utilization of the LADD procedure with tranexamic acid delivery followed by picosecond lasers can attenuate the PIH better than the utilization of picosecond lasers alone. Patients and methods: Ten post-traumatic cases of PIH in 10 patients (8 female and 2 male) with an average age of 34.2 ± 11.2 years were included in this clinical trial. Using block randomization to determine the treatment side, one side of each area of the PIH was separated from the midline into two halves belonging to the control and tranexamic acid groups. The half area of the tranexamic acid group was further topically applied with 10% tranexamic acid solution. This procedure was repeated every 6 weeks, four times in total. Results: The self-assessment of the hyperpigmentation and overall satisfaction of the treatment outcome were not significantly different between the treatment and control sides. Conclusions: This split-area study revealed that, compared with picosecond alone, there was no significant difference adopting tranexamic acid in LADD after nonablative fractional picosecond laser for PIH.

Synergistic Effect of 300 μm Needle-Depth Fractional Microneedling Radiofrequency on the Treatment of Senescence-Induced Aging Hyperpigmentation of the Skin

Aging-associated dermatological pigmentary diseases are associated with accumulation of senescence cells and the disruption of basement membrane due to chronic ultraviolet radiation (UVR) exposure. Our study is on the synergistic effect of the novel 300 μm needle-depth fractional microneedling radiofrequency (FMR) treatment and conventional Q-switched ND:YAG laser on aging-associated hyperpigmentation of the skin. The prospective controlled clinical trial of 25 Asian women revealed significantly higher improvements not only on wrinkles, but also on hyperpigmentation. Additional ex vivo study revealed significant reduction of pro-melanogenic markers as well as senescent keratinocytes, while increased expression of collagen type IV on the epidermal basement membrane, after additional FMR treatment on UV-irradiated human tissues. These results demonstrate that 300 μm needle-depth FMR might effectively remove senescent keratinocytes that secrete pro-melanogenic markers, and repair disrupted basement membrane, therefore preventing constant hyperpigmentation of the aged skin.

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.

Objective and Long-Term Evaluation of the Efficacy and Safety of a 1064-nm Picosecond Laser With Fractionated Microlens Array for the Treatment of Atrophic Acne Scar in Asians

BACKGROUND AND OBJECTIVE

Fractional 1064-nm picosecond-domain laser has recently been utilized for the treatment of atrophic acne scars and showed promising results. However, data on the safety and efficacy of this procedure in dark-skinned patients are limited. This prospective, self-controlled study was conducted to objectively evaluate the safety and efficacy of a 1064-nm picosecond laser coupled with a microlens array (MLA) for the treatment of atrophic acne scars on Asian skin.

STUDY DESIGN/MATERIALS AND METHODS

Twenty-six subjects of Fitzpatrick skin types (FSTs) III and IV with atrophic acne scars were enrolled. All subjects were treated with a 1064-nm picosecond laser (spot size of 8 mm, fluence of 1.0 J/cm² , a repetition rate of 10 Hz) in combination with the MLA handpiece for an average of three passes, for 6 monthly sessions. Objective (measurement of scar volume using three-dimensional (3D) photography and skin roughness analysis using ultraviolet A-light video camera) and subjective (clinical evaluation by two blinded dermatologists) assessments were obtained at baseline and at 1, 3, and 6 months after the final treatment.

RESULTS

Statistically significant reduction of the scar volume from baseline at 1, 3, and 6 months after the final treatment were observed by 3D photography and ultraviolet A-light video camera. At the 6-month follow-up, 50% (13 of 26) of the subjects were rated as having at least 50% improvement of the scars. The rate of improvement significantly increased from the 1-month follow-up to the 6-month follow-up (P = 0.013). Similarly, at the 6-month follow-up, the scar volume (P = 0.024) and skin roughness (P = 0.001) also significantly improved, in comparison with the baseline. Mild postinflammatory hyperpigmentation (PIH) was observed to develop in approximately 18% of all the treatment sessions. All cases of PIH were temporary and resolved within 4 weeks on average.

CONCLUSIONS

The 1064-nm picosecond laser with MLA is a safe therapeutic alternative for the treatment of atrophic acne scars in dark-skinned individuals. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.