Treatment of abdominal striae distensae in Fitzpatrick skin types IV to V using a 1064-nm picosecond laser with a fractionated microlens array

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.

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 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.

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.

The efficacy and safety of the innovative cold atmospheric-pressure plasma technology in the treatment of striae distensae: A randomized controlled trial

BACKGROUND

Available current therapeutics modalities for striae distensae (SD) provide inconsistently effective outcomes. There is ongoing research on innovative treatment modalities to find better treatment solutions.

OBJECTIVES

To evaluate the efficacy and safety of innovative cold atmospheric plasma (CAP) technology in the treatment of striae distensae.

METHODS

This study includes twenty-three patients with striae distensae. The body was divided into two halves. One side was randomly treated with CAP biweekly on the same treated side for five sessions with 30 days follow-up after the last session. Another half was left untreated. Efficacy assessment was done using patient and observer scar assessment scale (POSAS), patient satisfaction scales, and Antera 3D® skin imaging system. Safety assessment was evaluated using the visual analog scale (VAS) and adverse effects monitoring.

RESULTS

Patient and observer scar assessment scale, patient and observer overall opinion score, and patient and observer total score in a summary of all rated characteristics, comparing treated and untreated areas, showed a statistically significant reduction in all parameters after one treatment (*p-value <0.05). Patients rated satisfaction as a great improvement in 52.3%, moderate improvement in 39.1%, extreme improvement in 4.3%, and slight improvement in 4.3%. Adverse effects included small scabs, shallow wounds, and rash.

CONCLUSION

Cold atmospheric plasma is a safe and effective, innovative treatment modality for striae distensae with minimal side effects.

New Progress in Therapeutic Modalities of Striae Distensae

Striae distensae (stretch marks/striae gravidarum) is one of the common cosmetic problems that can cause psychological distress and anxiety to patients due to its disfiguring damage, especially for women. The etiology of striae distensae is currently unknown, and risk factors include low maternal age, family history of stretch marks, excessive weight gain during pregnancy, and high neonatal weight. This article reviews the latest literature on the most commonly used, most popular, and novel treatment modalities and analyzes the hot spots and difficulties in striae distensae treatment in recent years. Topical treatment modalities are mainly used as an adjunctive treatment. Ablative lasers and non-ablative lasers are the most popular, among which picosecond has been tried in striae distensae treatment in the last two years. Combined treatment modalities are currently a hot spot for SD treatment, and microneedle radiofrequency and fractional CO₂ laser combined with other treatments are the most common. Microneedle radiofrequency is the most commonly used and achieved therapeutic effect among the combined treatment modalities.

A prospective study to evaluate the treatment effect of pulsed dye laser on thyroidectomy hypertrophic scars using 3D imaging analysis

OBJECTIVES

The pulsed dye laser (PDL) is an effective modality for preventing and improving hypertrophic scars (HSs). However, the heterogeneity of the parameter settings of the laser and subjective scar assessment methods used in most studies resulting in uncertainty with treatment plans. Therefore, we investigated the treatment effect of the PDL (V-beam; Candela Laser Corporation) on HSs in post-thyroidectomy patients using three-dimensional imaging analysis and intended to provide a systemic and optimal treatment protocol.

METHODS

Nineteen patients with HS after thyroidectomy underwent eight treatment sessions with the 595 nm PDL (with the dose gradually increased by 0.5 J/cm² ) at 4- to 6-week intervals. Patients with an elevated lesion also received intralesional corticosteroid (ICS) treatment. After every two treatment sessions, we assessed the patients' HS using the Vancouver Scar Scale (VSS), a patient satisfaction questionnaire, and with a three-dimensional (3D) skin imaging device (Antera 3D™; Miravex Limited).

RESULTS

In repeated-measures analysis of variance, the mean VSS and patient satisfaction significantly improved (p < 0.001), with significant differences in these values observed until the sixth and eighth treatment sessions, respectively. In the quantitative analysis using Antera 3D™, the mean height, pigmentation, and vascularity scores were observed to be significantly improved (p < 0.001). Significant differences in these values were observed until the fourth, second, and eighth treatment sessions, respectively. Subgroup analysis according to ICS treatment showed no significant differences in scar characteristics between those with and without ICS treatment.

CONCLUSIONS

In this study, we found that the PDL was effective in reducing scar height, vascularity, and pigmentation in patients with thyroidectomy HS using 3D imaging analysis. Furthermore, we have suggested a cost-effective treatment plan with the 595 nm PDL.