Comparison of a 1064-nm neodymium-doped yttrium aluminum garnet picosecond laser using a diffractive optical element vs. a nonablative 1550-nm erbium-glass laser for the treatment of facial acne scarring in Asian patients: a 17-week prospective, randomized, split-face, controlled trial

Research Situation, Hotspots, and Global Trends in Laser Treatment of Acne Scars: A Bibliometric Analysis of Related Research From 2014 to 2024

BACKGROUND

Acne vulgaris is a chronic inflammatory skin condition, commonly resulting in acne scars. Treating acne scars remains a significant challenge in dermatology. With advancements in laser technology, its clinical use for treating acne scars has been increasing annually. However, bibliometric analysis on laser treatment for acne scars is lacking. This study aims to use bibliometrics to comprehensively understand the development trends and research hotspots in laser treatment for acne scars.

METHODS

Using "acne scar" and "laser" as search terms, literature on laser treatment of acne scars from 2014 to 2024 was retrieved from the Web of Science Core Collection (WoSCC) database. The literature data were visualized using VOSviewers, CiteSpace, and R software, generating maps of countries, research institutions, authors, journals, references, and keywords.

RESULTS

The analysis included 536 articles from 46 countries, with the United States and China leading in publications. Publications focusing on laser treatment of acne scars exhibit a consistent growth trend annually. Key research institutions include Mahidol University in Thailand, Cairo University in Egypt, and Hallym University in South Korea. The "Journal of Cosmetic Dermatology" had the highest number of articles in this field, while "Dermatologic Surgery" was the most cited publication. These publications involved contributions from 2135 authors, with Professor Manuskiatti Woraphong from Mahidol University in Thailand being the most prolific author in this field. Research on the efficacy of laser treatment for acne scars is a major focus in this field. Among the different types of lasers, CO2 lasers are the most commonly used. Emerging research focuses include therapies such as platelet-rich plasma, picosecond laser, trichloroacetic acid, and burn scar.

CONCLUSIONS

Treatment efficacy is the primary focus of research in the field of laser treatment for acne scars. Platelet-rich plasma, and novel picosecond lasers, have emerged as hot topics and trends in this research field. However, it is important to note that the impact factors of journals publishing in this field are currently low. Therefore, clinicians must consider and explore strategies for publishing high-quality clinical research in the future.

The 2910-nm Fiber Laser Is Safe and Effective for Improving Acne Scarring

BACKGROUND

Acne scarring results from the inflammation associated with acne papules, which alters dermal collagen, typically producing depressed scars. Lasers have been used to remodel skin improving the texture and appearance of acne scars. Herein, we investigate a new 2910 nm, erbium-doped, fluoride glass, fiber laser for improving acne scars. This novel laser delivers up to 5000 Hz low-energy pulses, providing a unique treatment modality.

METHODS

Fourteen subjects with rolling and/or boxcar acne scars were enrolled in this study. Thirteen subjects completed the final visit and received three treatments with the 2910 nm fiber laser at 6-8-week intervals. Eight subjects were Fitzpatrick type II and five were Fitzpatrick type III. Digital images were taken pre- and 1- and 3-months posttreatment and evaluated by two blinded reviewers in a randomized fashion for improvement. Subjects and the treating physician completed a Global Aesthetic Improvement Scale (GAIS) before treatment and at each visit to subjectively evaluate treatment effect. Histological analysis was performed on ex vivo lower eyelid skin samples. Side effects were evaluated by the treating physician and included erythema, edema, and pinpoint bleeding.

RESULTS

Evaluation of blinded digital images revealed a mean improvement of 47.3% ± 14.2% (mean ± SEM) 3 months following the final treatment. GAIS scores demonstrated improvement as evaluated by both the subjects and the treating physician. Side effects averaged trace-to-mild erythema, edema, and pinpoint bleeding.

CONCLUSION

This study shows that the 2910 nm, erbium-doped, fluoride glass, fiber laser is safe and effective for improving the appearance of acne scars.

Advances in the Application of Noninvasive Skin Imaging Techniques in Acne Scars

Acne scarring is a common sequela of acne vulgaris, which seriously affects facial esthetics. The treatment options for acne scars vary depending on the development stage, color, type, and location of scarring. The objective and precise assessment of acne scars is a prerequisite for treatment, and it is also an important means of monitoring the treatment effect. The traditional methods to evaluate the types and severity grade of acne scars are primarily based on subjective assessment by physicians, which lacks objectivity and accuracy. Novel noninvasive skin imaging techniques, such as skin surface imaging analysis systems, dermoscopy, reflectance confocal microscopy (RCM), high-frequency ultrasound (HFUS), optical coherence tomography (OCT), and multiphoton tomography (MPT), provide new tools for the rapid and objective assessment of acne scars. This article reviews the progress of skin imaging techniques in the diagnosis, classification, and efficacy evaluation of acne scars.

Fractional picosecond laser treatment of non-acne atrophic scars and scar erythema in Chinese patients

BACKGROUND

Fractional picosecond lasers (FPL) are reported to be effective and safe for atrophic acne scars and post-acne erythema. However, there is no evidence regarding the effectiveness and safety of FPL treatment for non-acne atrophic scars and scar erythema among Chinese patients.

METHODS

In this retrospective study, 12 Chinese patients with non-acne atrophic scars, including nine with scar erythema, were treated with one to three sessions of 1064 nm FPL treatment. Clinical improvement was objectively assessed through blinded evaluations by external physicians. A modified Manchester Scar Scale (mMSS) and the Clinician Erythema Assessment Scale (CEAS) were individually used to evaluate atrophic scars and scar erythema based on photographs. Physician-assessed and subject-assessed Global Aesthetic Improvement Scale (GAIS) were used to assess changes before and after FPL treatment. Patient satisfaction and adverse events were also documented.

RESULTS

Total mMSS scores, as well as three parameters (color, distortion, and texture), were significantly decreased after FPL treatment, with a mean reduction of 3.18 ± 1.60 in total scores (p < 0.05). The CEAS scores were significantly reduced from 2.41 ± 0.98 before treatment to 0.41 ± 0.40 at the final visit (p < 0.05). Based on physician-assessed and subject-assessed GAIS scores, 11 (91.7%) patients were improved after FPL treatment. 33.3% of patients were very satisfied, and 41.7% were satisfied. No serious, prolonged (> 3 weeks) adverse events were observed.

CONCLUSION

Our study suggests that 1064 nm FPL treatment may be a promising option for non-acne atrophic scars, especially with scar erythema. Further studies are needed to confirm our results.

Review of Fractional Nonablative Lasers for the Treatment of Dermatologic Conditions in Darker Skin Phototypes

BACKGROUND

Fractional nonablative lasers (NAFLs) have demonstrated efficacy and safety for treating dermatologic conditions in patients with darker skin phototypes. Nonablative lasers are preferred in darker skin tones due to lower risk of postinflammatory hyperpigmentation.

OBJECTIVE

This review aims to identify the ideal laser options and parameters for treating common dermatologic conditions in patients with skin types IV-VI.

MATERIALS AND METHODS

A comprehensive literature search was conducted on PubMed in May 2023. Of 1,065 articles were identified, and 40 articles met the inclusion criteria. The studies were classified based on design, dermatologic condition, and skin phototype of patients, and assigned levels of evidence according to the Modified Criteria of the Oxford Center of Evidence Based Medicine.

RESULTS

Strong level 1 evidence supports the treatment of melasma and atrophic scars using NAFL. Moderate level 2 evidence was found for using NAFL in acne vulgaris, striae, and skin rejuvenation; 45% of the studies examined skin types III-IV, 20% III-V, 7.5% II-IV, 5% II-V, 5% IV alone, and 2.5% I-IV.

CONCLUSION

Further research is needed to determine the optimal treatment modalities and parameters for skin types V and VI. Appropriate device selection and conservative treatment settings are crucial for optimizing outcomes and minimizing adverse events.

Efficacy and safety of 1064-nm fractional picosecond laser for the treatment of postmastectomy scars in transgender men: A randomized controlled trial

OBJECTIVES

Subcutaneous mastectomy is a crucial component of gender affirmation therapy for transgender men (TM), but the scars that result from this procedure can frequently impair their quality of life. This study aimed to assess the efficacy and safety of 1064-nm fractional picosecond laser (FxPico) treatment for hypertrophic and atrophic postmastectomy scars in TM.

METHODS

Twenty-two patients with a total of 35 pairs of bilateral symmetric mastectomy scars were enrolled. One of each pair of symmetric scars was randomly assigned to receive four FxPico treatments at 4-week intervals. All scars were evaluated using the modified Vancouver Scar Scale (mVSS) and three-dimensional imaging for scar roughness, melanin index, and hemoglobin index before each treatment session and at 1, 3, and 6 months following the last treatment. Additionally, participant-rated scar satisfaction (PSS) and scar improvement (Global Assessment Score, GAS), as well as adverse events were recorded.

RESULTS

During the 6-month follow-up period after the end of laser treatment sessions, the treated scars showed significant reductions in the mVSS compared to the untreated controls (p < 0.001), whereas the melanin index and hemoglobin index were not significantly different. Subgroup analysis of hypertrophic scars demonstrated statistically significant reductions in mVSS at 1 (p = 0.003) and 3 months (p = 0.041) after the end of laser treatments. PSS was significantly higher on the laser-treated scars than the controls (p = 0.008), and a participant-rated GAS of 2.95 ± 0.65 was found. There were no serious adverse events reported.

CONCLUSIONS

1064-nm FxPico could be utilized to treat mastectomy scars among TM, particularly the hypertrophic type.

Cosmetic Considerations in Dark-Skinned Patients

For dermatologists, diversities of human races result in an opportunity to encounter patients with various skin types. Cosmetic procedures have gained more popularity and become more accessible over the past decades. Thus, the selection of appropriate treatment protocol for each patient becomes inevitable. This review will focus on basic knowledge and key points in performing safe cosmetic-related procedures in patients with dark-complexioned skin. In terms of structure and function of the skin, people of color have equal epidermal thickness, corneocyte size and melanocyte number. However, they have more stratum corneum compaction, melanosome dispersion and melanocyte activity than fair skin individuals. Data regarding drug penetration and cutaneous irritation showed conflicting results. Superficial chemical peels and microdermabrasion can be done safely in dark-skinned patients. Medium-depth peel should be used with extreme caution. While deep-depth peel should be avoided at all times due to pigmentary and textural complications. Prolonged treatment interval, use of priming agents and sun protection are recommended. Injectable materials including botulinum toxin and soft tissue augmentation by hyaluronic acid filler can be done harmlessly in dark-skinned patients. Lasers and energy-based devices should be done with caution. Higher melanin dispersion and melanocyte activity acts as competitive chromophore. Pigmentary or textural changes can occur after aggressive treatment protocol. High energy setting, pulse stacking, short wavelength lasers and short treatment interval should be avoided in dark-skinned patients.

Efficacy of combined treatment with human adipose tissue stem cell-derived exosome-containing solution and microneedling for facial skin aging: A 12-week prospective, randomized, split-face study

BACKGROUND

Studies have reported promising results of mesenchymal stem cell therapies for skin aging. However, in the use of mesenchymal stem cells, some drawbacks including rarely possible tumorigenicity and low engraftment rates have limited their widespread clinical use. Adipose tissue stem cell-derived exosomes (ASCEs) are emerging as effective cell-free therapeutic agents.

AIMS

It was evaluated the clinical efficacy of combining the application of human ASCE-containing solution (HACS) with microneedling to treat facial skin aging.

METHODS

A 12-week, prospective, randomized, split-face, comparative study was conducted. Twenty-eight individuals underwent three treatment sessions separated by 3-week intervals and were followed up for 6 weeks after the last session. At each treatment session, HACS and microneedling were administered to one side of the face, and normal saline solution and microneedling were administered to the other side as a control.

RESULTS

The Global Aesthetic Improvement Scale score was significantly higher on the HACS-treated side than on the control side at the final follow-up visit (p = 0.005). Objective measurements obtained by different devices including PRIMOS Premium, Cutometer MPA 580, Corneometer CM 825, and Mark-Vu confirmed greater clinical improvements in skin wrinkles, elasticity, hydration, and pigmentation on the HACS-treated side than on the control side. The results of the histopathological evaluation were consistent with the clinical findings. No serious adverse events were observed.

CONCLUSIONS

These findings demonstrate that combined treatment using HACS and microneedling is effective and safe for treating facial skin aging.

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.

Efficacy and safety of 1565-nm nonablative fractional laser combined with mucopolysaccharide polysulfate cream for erythematous acne scars

PURPOSE

To evaluate the efficacy and safety of 1565-nm nonablative fractional laser (NAFL) combined with mucopolysaccharide polysulfate (MPS) cream in the treatment of erythematous acne scars.

METHODS

A total of 28 subjects with erythematous acne scars from June 2021 to April 2022 were enrolled. One side of each subject's face was randomly assigned to be treated with 1565-nm NAFL (at 2 sessions with four-week intervals) combined with MPS cream (twice daily) for 8 weeks, and the other side with 1565-nm NAFL combined with placebo cream. CBS® images and parameters, dermoscopic images and the quantitative data processed by ImageJ software, and quantitative global scarring grading system (GSS) score were obtained at baseline and after treatment. Subjects' satisfaction assessment was performed after treatment. Adverse events were recorded during treatment.

RESULTS

In CBS® parameters, the red area, red area concentration, and smoothness were improved more significantly on the 1565-nm NAFL combined with MPS cream side than on the 1565-nm NAFL combined with placebo cream side after treatment (p = 0.015, p = 0.013, and p = 0.021). For dermoscopy, both scar area and scar redness achieved a significantly greater percentage of improvement on the side of 1565-nm NAFL combined with MPS cream than the side of 1565-nm NAFL combined with placebo cream after treatment (p = 0.005 and p = 0.041). The reduction of quantitative GSS score and Subjects' satisfaction assessment were similarly superior on the 1565-nm NAFL combined with MPS cream side. Temporary erythema was experienced by all subjects after each 1565-nm NAFL treatment. No subject reported intolerance or allergy to the cream during follow-up.

CONCLUSIONS

The combined application of 1565-nm NAFL and MPS cream could be an effective and safe treatment for erythematous acne scars. ImageJ software enables quantitative evaluation of dermoscopic images of acne scars.

Efficacy and safety of fractional 1064-nm picosecond laser for atrophic traumatic and surgical scars: A randomized, single-blinded, split-scar-controlled study

OBJECTIVE

A fractional 1064-nm picosecond laser is an efficient and safe treatment for atrophic acne scars. However, evidence of using a picosecond laser for atrophic posttraumatic and surgical scar therapy is lacking. This study aimed to evaluate the efficacy and safety of using a 1064-nm picosecond laser with a microlens array (MLA) for the treatment of atrophic posttraumatic and surgical scars.

METHODS

This was a prospective, intraindividual, single-blinded, randomized split-lesion-controlled trial. Twenty-five subjects with atrophic traumatic or surgical scars that existed for more than 1 year were enrolled. All atrophic scars were divided at the midline into two halves and randomly assigned to a treatment or control side. The treatment group was treated with a 1064-nm picosecond laser with an MLA handpiece (spot size: 6-8 mm, fluence: 1.0-1.2 J/cm² , repetition rate: 5 Hz, three passes) for 3 monthly sessions. The scar volumes were objectively measured using a three-dimensional (3D) photograph at baseline, 1 month after the first and second treatments, and 3 and 6 months after the final treatment. Subjective assessments were conducted by a blinded dermatologist and patients' self-assessment to evaluate improvements at 3 months after the final treatment.

RESULTS

The treated sides exhibited a significant volume reduction, with statistically significant improvements over the control group at 1 month after the first and second treatments and at 3 months after the final treatment (p = 0.024, 0.005, and 0.019, respectively). At 3 months after the final treatment, a blinded dermatologist correctly identified the treated side in 24 of 25 patients (96%). The patients rated the improvements as excellent (>75%) and marked (50%-75%) in 36% and 48% of patients, respectively.

CONCLUSION

At 3 months, the 1064-nm picosecond laser with a fractionated MLA can significantly reduce the posttraumatic and postsurgical atrophic scar volume in patients with Fitzpatrick skin types III-V. Insufficient data preclude inferences regarding efficacy at 6 months.

[Picosecond lasers in dermatology]

BACKGROUND

The picosecond laser is one of the latest laser systems in dermatology and was originally developed to optimize tattoo removal. Advances in this technology has expanded the use of the picosecond laser to numerous other indications.

OBJECTIVES

This article provides an overview of the technical background as well as the indications of the picosecond laser in dermatological laser medicine and elucidates the possibilities and limits of this laser system.

MATERIALS AND METHODS

The article is based on a review of the current literature as well as experience from clinical practice in a university laser department.

RESULTS

The picosecond laser enables a particularly gentle and effective treatment due to ultra-short pulses and the principle of laser-induced optical breakdown. Compared to Q‑switched lasers, the picosecond laser has fewer side effects and is associated with lower pain intensity and shorter downtime. In addition to the removal of tattoos and pigmentary disorders, it is also used in the treatment of scars and rejuvenation.

CONCLUSIONS

The picosecond laser has a wide range of indications in dermatological laser medicine. The current data indicate that the laser is an effective method with few side effects. Further prospective studies have to be conducted to assess the efficacy, tolerability and patient satisfaction in an evidence-based manner.

Energy-based devices in the treatment of acne scars in skin of color

BACKGROUND

Acne scarring is disfiguring and psychologically taxing on patients. Many energy-based modalities have emerged and been studied for the treatment of acne scarring; however, there is a paucity of these studies in skin phototypes IV-VI.

OBJECTIVE

To review the medical literature and discuss the most significant studies regarding safety and efficacy of energy-based devices (ablative lasers, non-ablative lasers, and radiofrequency microneedling) in the treatment of ethnic skin (skin phototypes IV-VI).

METHODS

A literature search was conducted using the PubMed database and bibliographies of relevant articles.

RESULTS

Ablative and non-ablative lasers have proven to be effective for treatment of acne scars in ethnic skin. The risk of developing adverse effects such as post-inflammatory hyperpigmentation is contingent upon several factors including skin phototype, laser device, fluence, and moreso density settings. Non-ablative fractional lasers have been considered first line for the treatment of acne scars in skin of color due to their better safety profile; however, they are less efficacious and require more treatments compared to ablative lasers. Studies regarding efficacy and safety of radiofrequency microneedling for treatment of acne scarring in skin of color are limited, but are promising.

CONCLUSION

Ablative lasers, non-ablative lasers, and radiofrequency microneedling are all useful treatments for acne scarring in ethnic skin when appropriate settings are used. Further head-to-head studies are needed to evaluate their efficacy and safety in darker skin phototypes V-VI.

Efficacy and safety of low-dose oral isotretinoin monotherapy versus combined therapy with picosecond laser for the treatment of acne scars in Asian population

PURPOSE

Acne scars are common in patients with moderate to severe acne. Isotretinoin is the first-line treatment for those patients, but whether oral isotretinoin can improve acne scar is not clear. Picosecond lasers (FxPico) has been reported to improve acne scars. In the present study, we evaluated the clinical efficacy of low-dose isotretinoin with or without FxPico treatment for acne scars.

MATERIALS AND METHODS

A total of 48 patients with acne scars were enrolled and were randomly assigned to receive low dose oral isotretinoin or not. For all the patients in both treatment groups, one side of face were randomly assigned to be treated with picosecond laser. Assessments, including photos, échelle d'évaluation clinique des cicatrices d'acné (ECCA) and Global Acne Grading System (GAGS) score, the number of lesions, melanin and erythema indexes, transepidermal water loss were assessed at 0, 1, 2, and 3 month. Side effects, Dermatology Life Quality Index (DLQI) and satisfaction were recorded before and after the study.

RESULTS

A total of 44 patients completed the study (24 received oral low dose isotretinoin and 20 did not). Low dose oral isotretinoin treated group showed significant improvement on ECCA (from 112.5 [50-180] to 105 [50-160]), GAGS score (from 12.6 ± 3.3 to 10.1 ± 3.0), the count of papules (from 4.3 ± 3.7 to 1.0 ± 1.5) than the blank group, and higher improvement were noticed after isotretinoin combined with FxPico. All the side effects were temporary and tolerable, no adverse effects were observed. Higher DLQI and patients' satisfaction were achieved by oral isotretinoin alone and isotretinoin combined with FxPico.

CONCLUSIONS

This is the first paper showing the improvement of scars by early low dose-isotretinoin intervention with or without the combination of picosecond laser. Early intervention with oral low-dose isotretinoin is effective for the treatment and prevention of acne scars, the combined therapy with FxPico can achieve better outcome.

Morphologic and molecular biologic analyses of the skin rejuvenation effect of the fractional 1064-nm picosecond laser: An animal study

OBJECTIVES

Application of the picosecond laser in the field of dermatology has expanded from tattoo removal to skin rejuvenation on a clinical basis. Although various mechanisms of pigment removal have been elucidated, the molecular changes associated with skin rejuvenation have yet to be identified. The aim of this study was to explore the theoretical basis and to evaluate the efficacy of skin rejuvenation using a 1064-nm fractional picosecond laser in a mouse model.

METHODS

We conducted an in vivo study using a fractional picosecond laser on the skin of old and young female hairless mice and performed topographical, histological, micro-, and electron microscopic assessments.

RESULTS

The topography of the skin surface was enhanced and showed increased dermal thickness on histological examination. Electron microscopy revealed disarranged collagen bundles with microspaces and vascular leakage in the upper dermis. Levels of collagen synthesis markers and various inflammatory cytokines, such as procollagens, interleukin-1β, tumor necrosis factor-α, and heat shock proteins, were elevated in the laser-treated skin.

CONCLUSIONS

This study provides a possible mechanism for the skin rejuvenation effect of fractional picosecond laser that has been reported previously in clinical observations. Based on our findings, the fractional picosecond laser could be widely applied in clinical settings where dermal regeneration and promotion of skin rejuvenation is required.

An update on fractional picosecond laser treatment: histology and clinical applications

Picosecond lasers have a very short pulse duration and a high peak power density. When fractional optical delivery systems are attached to picosecond lasers, they generate an array of concentrated microspots with a high fluence surrounded by areas with a low fluence. This article discusses the histologic characteristics and clinical applications of fractional picosecond laser treatment. Fractional picosecond laser produces laser-induced optical breakdown (LIOB) and laser-induced cavitation (LIC) in the epidermis and dermis respectively, and can encourage skin regeneration and dermal remodeling. It has been shown that fractional picosecond laser has a positive effect on facial photoaging, enlarged facial pores, dyspigmentation, wrinkles, and atrophic scars. Further research is still needed to confirm the benefits of fractional picosecond lasers.

Early acne scar intervention with 1064 nm picosecond laser in patients receiving oral isotretinoin: a randomized split-face controlled pilot study

Early acne scar intervention is important. Oral isotretinoin is widely used in patients with moderate to severe acne. Picosecond laser has shown a promising effect on scar clearance. However, there is a lack of reports on the efficacy and safety of early acne scar management by using 1064-nm picosecond laser in patients receiving low-dose oral isotretinoin. Twenty-four patients with atrophic acne scars of Fitzpatrick skin type III to V were enrolled. All patients were receiving low-dose oral isotretinoin (0.12-0.22 mg/kg/day) during the treatment. The face of the participants was randomly assigned to receive 2 sessions of fractional picosecond 1064 nm Nd: YAG laser (FxPico) treatment and 2 follow-ups, with an interval of 1 month (month 0-3). Clinical efficacy and safety were assessed by photographs, ECCA grading scale, the number of scar lesions melanin and erythema indexes (MI and EI), TEWL, DLQI, and patient satisfaction and the adverse events were recorded on every visit. FxPico significantly decreased the ECCA score and showed higher improvement in the ECCA score. FxPico treated side achieved a significant reduction in all acne scar types, while only boxcar scars and rolling scars showed higher improvement. TEWL but not MI or EI were significantly improved. DLQI and patient satisfaction were higher with the FxPico-treated side than control side. No adverse effects were observed and all the side effects observed were temporary and tolerable. Early intervention by FxPico on patients receiving low-dose oral isotretinoin is a safe and effective modality to improve atrophic acne scars.

Enhancement of gold nanorods-assisted photothermal treatment on cancer with laser power in stepwise modulation

OBJECTIVES

Photothermal therapy (PTT) is a minimally invasive or noninvasive method by destructing cancer cells through selective thermal decomposition. However, a long period of laser irradiation to achieve coagulative necrosis often causes unfavorable thermal damage to the surrounding healthy tissue. The current study aims to evaluate the feasibility of temporal power modulation to improve the treatment efficacy of gold nanorods-assisted PTT against tumor tissue.

MATERIALS AND METHODS

A total of 25 µg/ml of PEGylated gold nanorods (PEG-GNR) was used as an absorbing agent during 1064 nm laser irradiation for PTT. Temperature monitoring was conducted on the aqueous solution of PEG-GNR for dosimetry comparison. For in vivo tests, CT-26 tumor-bearing murine models with PEG-GNR injected were treated with three irradiation conditions: 3 W/cm² for 90 s, 1.5 W/cm² for 180 s, and 3 W/cm² for 60 s followed by 1.5 W/cm² for 60 s (modulated). Ten days after the treatments, histology analysis was performed to assess the extent of coagulation necrosis in the treated tissues.

RESULTS

The temporal power modulation maintained the tissue temperature of around 50°C for a longer period during the irradiation. Histology analysis confirmed that the modulated group entailed a larger coagulative necrosis area with less thermal damage to the peripheral tissue, compared to the other irradiation conditions.

CONCLUSION

Therefore, the power-modulated PTT could improve treatment efficacy with reduced injury by maintaining the constant tissue temperature. Further studies will examine the feasibility of the proposed technique in large animal models in terms of acute and chronic tissue responses and treatment margin for clinical translations.

A systematic review of evaluating the efficacy of acne scar treatment by Fractional Laser with or without using adjunctive treatments

Fractional laser (FL) resurfacing has proved its effectiveness in acne scars treatments. To evaluate the efficacy of Fractional laser systems for treatment of acne scars as a monotherapy, and as adjunctive therapy with other treatment types. A systematic literature review was performed by searching the electronic databases PubMed, Google Scholar, and Embase. Fractional laser has proven therapeutic efficacy of over 26% in treating acne scars, with minor and transient side effects, and well-tolerant pain. The application of PRP not only accelerated recovery and reduced adverse events, but also enhanced localized collagen neogenesis and redistribution. The addition of surgical treatments to Fractional Laser Systemes (FLS) therapy delivers the best treatment results for Icepick scars. Fractional laser is an effective tool for treating acne scars. The degree of effectiveness varies according to the laser parameters, the number of treatment sessions, skin photo type, the severity and the type of scars. The application of Platelet-Rich Plasma (PRP) and Fractional Radiofrequency Microneedle (FRM) in addition to the FL treatment improves the therapeutic efficacy and reduces the appearance of Post Inflammatory Hyper-Pigmentation (PIH), and is the ideal treatment for dark-skinned patients. FL therapy along with surgical methods such as subsicion and punch techniques provided the best improvements for deep scars.

Energy-based devices for the treatment of acne scars: 2021 international consensus recommendations

BACKGROUND AND OBJECTIVES

Acne scars are one of the most distressing and long-term consequences of acne vulgaris, with damaging effect on a person's physical, mental, and social well-being. Numerous treatment options are available including surgical and nonsurgical techniques, depending on the clinical presentation. Although considerable advances in the development of new treatment technologies and applications have been made in the last decade, international treatment guidelines and reimbursement schemes have not yet caught up with current knowledge and practice in many centers. The authors intend to highlight the potential utility of energy-based devices (EBDs) for acne scarring, offer recommendations for safe and efficacious treatment, and provide consensus-based EBD treatment options based on varying presentations demonstrated in a series of real-life clinical photographs.

STUDY DESIGN/MATERIALS AND METHODS

An international panel of 24 dermatologists and plastic surgeons from 12 different countries and a variety of practice backgrounds was self-assembled to develop updated consensus recommendations for the treatment of acne scars. A two-step modified Delphi method took place between March 2020 and February 2021 consisting of two rounds of emailed questionnaires. The panel members approved the final manuscript via email correspondence.

RESULTS

The manuscript includes a comprehensive discussion and panel recommendations regarding the following topics: 1. the role of EBD in mitigating and treating acne scars in a patient with active acne, 2. the use of various EBDs for the treatment of different acne scar types with special focus on commonly used laser platform such as vascular lasers, ablative fractional lasers (AFLs) and non-AFLs (NAFLs), 3. treatment combinations, and 4. acne scar treatments in skin of color. The last part comprised of 10 photos of real-life clinical cases with the panel recommendation treatment plan to achieve best aesthetic outcome.

CONCLUSION

Panel members were unanimous in their view that EBDs have a role in the management of acne scars, with AFLs, NAFLs, vascular lasers, and RF devices preferentially selected by most of the panel experts. EBDs are considered a first-line treatment for a variety of acne scar types and patients without access to these treatments may not be receiving the best available care for optimal cosmetic results. Future high-quality research and updated international treatment guidelines and reimbursement schemes should reflect this status.

Dependence of laser-induced optical breakdown on skin type during 1064 nm picosecond laser treatment

The current study aims to evaluate the dependence of laser-induced optical breakdown (LIOB) on skin types by using 1064 nm picosecond laser with micro-lens arrays (MLA) and diffractive optical elements (DOE). Both black and white skin tissues were examined to comparatively assess the LIOB effects in the skin in terms of laser-induced vacuolization. The black skin irradiated at 3.0 J/cm² demonstrated that MLA yielded a deeper distribution (180-400 μm) of laser-induced vacuoles with a size of 67 μm, compared to DOE (180-280 μm; 40 μm in size). However, the white skin presented that MLA created larger vacuoles (134 μm in size) in a smaller number at deeper distributions (125-700 μm) than MLA with the black skin. DOE generated no laser-induced vacuolization in the white skin. The white skin tissue with inherent higher scattering could be responsible for deeper vacuolization after the picosecond laser treatment. Further investigations are expected to determine the optimal treatment conditions for various skin types.

Efficacy and Safety of Treatment with Fractional 1,064-nm Picosecond Laser with Diffractive Optic Element for Wrinkles and Acne Scars: A Clinical Study

Background

Fractional picosecond lasers is effective for the treatment of wrinkles or acne scars.

Objective

To investigate the safety and efficacy of treatment with a fractional 1,064-nm picosecond laser with a diffractive optic element for facial wrinkles and acne scars.

Methods

This prospective open-labeled trial comprised 22 subjects with facial wrinkles or acne scars. Subjects received three laser treatments with a fractional 1,064-nm picosecond laser at 3-week intervals. The efficacy and safety were evaluated at every visit and 2 months after the final treatment (14 weeks from the first treatment session). Global photographic assessments were performed by three blinded dermatologists and the subjects. Skin profilometry was performed using three-dimensional digital photographs; viscoelasticity was measured.

Results

The overall mean global improvement scores assessed by the dermatologists at weeks 3, 6, and 14, were 1.8±1.46, 2.5±1.88, and 3.5±1.84, respectively, and those assessed by the subjects were 2.7±2.08, 4.1±2.24, and 5.0±2.52, respectively. Skin profilometry showed significant improvements in the skin wrinkles, texture, depressions, and pores. The gross elasticity and skin firmness significantly improved by 10.96% and 9.04%, respectively. The major adverse reactions were erythema, pruritus, and petechiae, which disappeared within 2~3 days.

Conclusion

The fractional 1,064-nm picosecond laser is an effective and safe therapeutic modality for skin rejuvenation.

Comparison of fractionated frequency-doubled 1,064/532 nm picosecond Nd:YAG lasers and non-ablative fractional 1,540 nm Er: glass in the treatment of facial atrophic scars: a randomized, split-face, double-blind trial

Background

Laser treatment of acne scars is common, but quality evidence on its efficacy is still needed. Our study aimed to compare picosecond laser and non-ablative fractional laser’s efficacy and safety in treating acne atrophic scars.

Methods

This was a randomized, split-face double-blind trial recruiting patients with acne atrophic scars. Facial halves were randomly divided and treated with fractionated frequency-doubled 1,064/532 nm picosecond Nd:YAG laser or non-ablative fractional 1,540 nm Er: glass laser. ECCA score (echelle d'evaluation clinique des cicatrices d’acne) and skin flatness measured with a non-invasive phaseshift rapid in vivo measurement of skin (PRIMOS) system were evaluated one month after the last treatment.

Results

Twenty-two Fitzpatrick skin type IV patients were included in this study, with an average age of 29.68 years, an average duration of acne scars of 8.8 years. Picosecond laser impacted all acne scar types (before and after treatment; P=0.000 for all types, P<0.001 for V-type, P=0.002 for U-type, and P=0.021 for M-type) and more pronounced effect on ECCA score than non-ablative laser for V-type and U-type acne scars. After treatment, each treatment site’s height was significantly lower than that before treatment (P=0.041) in the picosecond group but not in the non-ablative group (P=0.785). The reported erythema rate was higher in patients treated with a picosecond laser, while edema, exudation, purpura, pain, and long-term AEs were similar between the groups.

Conclusions

Fractionated frequency-doubled 1,064/532 nm Picosecond Nd: YAG laser showed better efficacy in treating acne atrophic scars than the alternative and provided satisfactory safety with added improvement in pores and the glossiness of the skin.

Registration number

ChiCTR2100045982 (comparison of fractionated frequency-doubled 1,064/532 nm picosecond Nd: YAG lasers and nonablative fractional 1,540 nm Er: glass in the treatment of facial atrophic scar: a randomized, split-face, double-blind controlled trial).

Outcomes and adverse effects of ablative vs nonablative lasers for skin resurfacing: A systematic review of 1093 patients

It is generally believed that ablative laser therapies result in prolonged healing and greater adverse events when compared with nonablative lasers for skin resurfacing. To evaluate the efficacy of ablative laser use for skin resurfacing and adverse events as a consequence of treatment in comparison to other modalities, a PRISMA-compliant systematic review (Systematic Review Registration Number: 204016) of twelve electronic databases was conducted for the terms "ablative laser" and "skin resurfacing" from March 2002 until July 2020. Studies included meta-analyses, randomized control trials, cohort studies, and case reports to facilitate evaluation of the data. All articles were evaluated for bias. The search strategy produced 34 studies. Of 1093 patients included in the studies of interest, adverse events were reported in a total of 106 patients (9.7%). Higher rates of adverse events were described in nonablative therapies (12.2% ± 2.19%, 31 events) when compared with ablative therapy (8.28% ± 2.46%, 81 events). 147 patients (13.4%) reported no side effects, 68 (6.22%) reported expected, transient self-resolving events, and five (0.046%) presented with hypertrophic scarring. Excluding transient events, ablative lasers had fewer complications overall when compared with nonablative lasers (2.56% ± 2.19% vs 7.48% ± 3.29%). This systematic review suggests ablative laser use for skin resurfacing is a safe and effective modality to treat a range of pathologies from photodamage and acne scars to hidradenitis suppurativa and posttraumatic scarring from basal cell carcinoma excision. Further studies are needed, but these results suggest that ablative lasers are a superior, safe, and effective modality to treat damaged skin.