Nonablative Fractional Diode Laser Resurfacing (1440 nm and 1927 nm) for Photoaged Skin

Supplemental Digital Content is Available in the Text.

Abstract

BACKGROUND

Nonablative lasers treat photoaged skin and stimulate new collagen formation while sparing epidermal damage.

OBJECTIVE

To evaluate the effectiveness and safety of nonablative fractional diode combination laser skin resurfacing treatment (1440 and 1927 nm) in mild-to-moderate photoaged skin.

MATERIALS AND METHODS

The entire face was treated with both 1440-nm and 1927-nm wavelengths per treatment, with a total of 4 treatments spaced 1 month apart. Follow-up occurred at 1 and 3 months post-treatment. Outcomes were improvement in the appearance of ≥1 measure of photodamage (rhytides, skin texture, dyschromia/pigment, skin radiance, pore size, and overall appearance) at the 3-month (primary) and 1-month (secondary) follow-up visits. Safety was monitored throughout the study.

RESULTS

Participants (N = 28; 89% female; mean age, 40 years) experienced significant mean improvement from baseline in all measures of photodamage with combination laser treatment at 1 and 3 months post-treatment (all p < .001). No serious adverse events occurred. Post-treatment erythema and edema were minimal, and pain levels remained consistent throughout treatment. Most participants (96.4%) considered their overall appearance as improved and expressed satisfaction with treatment outcomes.

CONCLUSION

Nonablative combination laser skin resurfacing treatment was well tolerated and significantly improved measures of photodamage in photoaged skin across diverse skin types.

A nonablative fractional diode laser with a 1440-nm wavelength handpiece (Clear + Brilliant laser system; Solta Medical, Bothell, WA) was approved by the US FDA in 2011 for general skin resurfacing, with additional approval in 2012 for its 1927-nm handpiece (Clear + Brilliant Perméa; Solta Medical, Bothell, WA).¹ The system offers the flexibility to deliver 2 wavelengths through separate handpieces: 1927 nm at a fixed depth of 170 μm and 1440 nm at a depth of 280 to 390 μm.² Separately, both handpieces have shown effectiveness for the rejuvenation of photodamaged skin and clinical improvements in skin tone, texture, rhytides, dyschromia, and reduction in detectable skin pores.³ In 40 patients with photoaged skin, 6 treatments with the 1927-nm wavelength handpiece alone or in combination with aqueous serum resulted in clinician-rated improvements in rhytides, skin texture, and dyschromia.⁴ In addition, the use of the 1927-nm wavelength handpiece demonstrated efficacy in facial resurfacing for participants with postinflammatory hyperpigmentation and melasma, which are exacerbated by ultraviolet light.⁵ In a separate study of 10 participants with Fitzpatrick skin types III to V and facial photodamage, 4 treatments with the 1440-nm wavelength handpiece significantly improved skin roughness, rhytides, and dyspigmentation at 4 weeks post-treatment.⁶

Despite the proven effectiveness of both handpieces, combined treatment in photoaged skin has not been well characterized. In addition, there is a need for further investigation of this technology in patients with diverse skin types. This prospective study assessed the effectiveness and safety of a nonablative fractional combination laser wavelength treatment using both 1440-nm and 1927-nm handpieces in participants with mild-to-moderate photoaging across Fitzpatrick skin types I to V.

Methods

Device Description

The nonablative fractional diode laser combination wavelength system (Clear + Brilliant Touch laser system) consists of a console and 2 versions of the laser handpiece. The console connects to the power source, and the handpieces produce laser energy delivered through disposable treatment tips. The system includes both a 1440-nm (original) and a 1927-nm (Perméa) handpiece, allowing for targeted treatment of different tissue depths. The 2.5 W 1440-nm wavelength handpiece has 3 fixed energy levels: low energy (280 μm depth and 2% coverage, assuming 4 total passes across the treatment area), medium energy (340 μm depth and 3.5% coverage), and high energy (390 μm depth and 4.5% coverage). The 1 W 1927-nm wavelength handpiece has a fixed energy level (5 mJ/pulse) with a depth of 170 μm and coverage of 2.5% (low), 3.75% (medium), or 5% (high), assuming 4 total passes.

Eligibility Criteria

Male and female adults aged 18 to 65 years with any Fitzpatrick skin type and mild (I)-to-moderate (II) photoaging classification according to the Glogau Photodamage Scale were eligible for inclusion in this prospective, single-center study. Participants were required to have no more than rhytides and mild elastosis based on the Fitzpatrick wrinkle and elastosis scale (class I–II, score 1–6). Individuals with a history of allergic reaction to lidocaine; recent or active infection; a serious skin condition (e.g., skin cancer, active infection, cold sores, open wounds, rashes, burns, inflammation eczema, psoriasis); an immune-compromising condition; sensitivity to light or photosensitizing agents; use of systemic steroids; recent use of retinoids; current treatment with isotretinoin (or with drugs in a similar class); recovery from a cosmetic procedure within the previous 6 months (i.e., chemical peel, mechanical peel, or laser resurfacing); recent Botulinum toxin injections or dermal fillers; sunburn or recent sun exposure on the treatment area; and who were pregnant, breastfeeding, or planning to become pregnant during the study were excluded.

Study Procedures

Before each treatment visit, participants were instructed to wash their face with CeraVe (L’Oréal S.A., Clichy, France) cleanser and to not apply topical facial products on the morning of treatment. Thirty minutes before each treatment, the face was cleansed with chlorhexidine antiseptic skin cleaner, and a topical anesthetic of 7% lidocaine/7% tetracaine was applied. The anesthetic was then fully wiped off, and the face was cleansed again with chlorhexidine antiseptic skin cleaner and allowed to dry. Each participant was provided protective laser eye shields, and staff wore laser goggles with appropriate protection range for the system laser wavelengths and optical density of ≥5.

At each treatment visit, the participant's entire face underwent treatment using both the 1440-nm and 1927-nm handpieces. The 1440-nm handpiece was used first, followed by the 1927-nm handpiece. A single-use tip was used, and the device was preset for 3200 cm² treatment area coverage or for treatment time of 40 minutes. The treatment zones on the face received 4 passes of both the 1440-nm and 1927-nm handpieces (2 horizontal passes and 2 vertical passes), resulting in a total of 8 passes per zone. Patients were treated with the highest settings, but adjustments could be made to lower settings based on participant tolerance. CeraVe moisturizer and sun protection factor (SPF) 30+ sunscreen were immediately applied to the entire face after treatment. Postcare instructions included washing the face with CeraVe gentle cleansing product only, avoiding the use of abrasive facial cleansers or brushes, and applying daily SPF 30+ and CeraVe moisturizer at least twice daily.

Laser treatment was administered over a period of 4 consecutive monthly visits (Treatment Visits 1–4). Post-treatment follow-up visits were scheduled at 1 and 3 months after the final treatment session. All protocols and study materials were approved by the study center's institutional review boards.

Photography

Standard 2D photographic images were captured through the VISIA CA imaging system (Canfield Scientific, Inc, Parsippany, NJ). The same standardized photography views (right, left, and front-facing) were used throughout the study, and images were taken at baseline; at 1 month after treatments 1, 2, and 3; and at 1 and 3 months after final treatment. Photographs were used to assess improvements in the appearance of photodamage by the investigator and for participant assessment of changes in appearance.

Outcomes

Effectiveness of the combination wavelength laser treatment was based on improvement in the appearance of ≥1 measurement of photodamage (rhytides, skin texture, dyschromia/pigment, skin radiance, pore size, and overall appearance) assessed by a quartile improvement scale: 0 = no improvement, 1 = minor/mild (1%–25%) improvement, 2 = moderate (26%–50%) improvement, 3 = marked (51%–75%) improvement, and 4 = very significant (76%–100%) improvement. Investigators assessed improvements at the 1-month (secondary end point) and 3-month (primary end point) post-treatment follow-up visits, compared with a baseline reference photograph. Other end points included participant-rated assessment of changes in appearance from baseline to the 3-month post-treatment follow-up visit, reported using the Subject Modified Global Aesthetic Improvement Scale (GAIS; 1 = very much improved to 7 = very much worse). Participant satisfaction was also reported with a 5-point Likert scale (1 = very dissatisfied to 5 = very satisfied) at 3 months post-treatment.

At each treatment visit, pain and discomfort were measured using a visual analog scale (VAS) from 0 (no pain) to 10 (unbearable pain) within 60 minutes of each treatment, and immediate post-treatment erythema and edema were evaluated on a scale of 0 (none) to 3 (severe). At the 1-month and 3-month post-treatment follow-up visits, skin responses (erythema, edema, dryness/flakiness, hypopigmentation, hyperpigmentation, blistering, and scarring) were evaluated on a scale of 0 (none) to 3 (severe). The frequency of serious adverse events was monitored throughout the study.

Statistical Analysis

The intent-to-treat (ITT) population, comprising all participants who received treatment, participated in ≥1 postbaseline evaluation, and were not otherwise disqualified, was the primary population for all statistical analyses. Investigator quartile improvement scores, safety parameters, VAS scores, and participant satisfaction were reported with descriptive statistical summaries. The Wilcoxon signed-rank test was used to determine the statistical significance of the change in the investigator quartile improvement score from baseline. All statistical tests were 2-sided at α = 0.05 significance level with no corrections for multiple testing. Statistical analyses were performed using SAS software version 9.4 (SAS Statistical Institute, Cary, NC).

Results

Study Population

Overall, 29 individuals were enrolled: 28 individuals were included in the ITT population, and 1 individual discontinued before first treatment because of an adverse event (allergic reaction to hydroquinone). Demographics and baseline characteristics of the 28 study participants (89.3% female; mean age, 39.9 years) are summarized in the Supplemental Digital Content 1 (Table 1, http://links.lww.com/DSS/B497). The proportion of Fitzpatrick skin types was as follows: type I: n = 1 (3.6%); type II: n = 6 (21.4%); type III: n = 13 (46.4%); type IV: n = 6 (21.4%); type V: n = 2 (7.1%). Most participants (82.1%) had moderate photoaging and moderate Fitzpatrick wrinkle (67.9%) and elastosis (71.4%) ratings.

Effectiveness

Statistically significant improvements with nonablative laser combination wavelength treatment were observed in all parameters of photodamage (rhytides, skin texture, dyschromia/pigment, skin radiance, pore size, and overall appearance; p < .001; Figure 1) at 1 and 3 months post-treatment compared with a baseline photograph. At 3 months post-treatment, investigators reported the majority of improvements as “marked” or “very significant” in all parameters. Representative images at baseline and post-treatment are presented in Figure 2 and in Supplemental Digital Content 1 (Figure 1, http://links.lww.com/DSS/B497).

Figure 1.

Mean investigator quartile improvement scores in measures of photodamage at 1 month (secondary end point) and 3 months (primary end point) after the final treatment. All comparisons to baseline were significant as compared with the constant 0 (Wilcoxon signed-rank test, p < .001).

Figure 2.

Representative images of a patient with Fitzpatrick skin type I. Improvements in the appearance of photodamage (rhytides, skin texture, dyschromia/pigment, skin radiance, pore size, and overall appearance) were assessed using the quartile improvement score comparing standard 2D baseline photographs captured through the Canfield VISIA CA system under normal and ultraviolet light. Images provided with patient consent.

Treatment Satisfaction

At the 3-month post-treatment assessment, all participants reported having a favorable appearance (GAIS score of 1, 2, or 3) compared with before treatment. Specifically, 29% (8/28) of participants rated themselves as very much improved, 53.6% (15/28) as much improved, and 17.9% (5/28) as improved. At the same assessment, nearly all participants (96.4%) expressed satisfaction with the treatment outcome, while 1 (3.6%) was neither satisfied nor dissatisfied. Among the 27 participants who expressed satisfaction, 17 (63.0%) were “very satisfied” and 10 (37.0%) were “satisfied.”

Safety

The mean participant-reported pain levels remained consistent throughout the treatment phase and ranged from 4.39 (Treatment Visit 1) to 4.89 (Treatment Visit 4). Numerical reductions in mean erythema and edema severity scores were observed at both the 1-month and 3-month post-treatment follow-up visits compared with the treatment phase (see Supplemental Digital Content 1, Figure 2, http://links.lww.com/DSS/B497). At 3 months post-treatment, no participants reported events of erythema or edema. No events of dryness/flakiness, hypopigmentation, hyperpigmentation, blistering, or scarring were reported at the 1-month or 3-month post-treatment follow-up visits. No serious adverse events were reported at any point during the treatment or post-treatment periods.

Discussion

Nonablative fractional diode lasers are effective for resurfacing photodamaged skin,^4,6 but the efficacy of combined treatment with both 1440-nm and 1927-nm handpieces has not been well characterized. Furthermore, it is crucial to evaluate the efficacy and safety of this treatment across diverse skin types, as patients with darker skin types experience disproportionate rates of melasma and postinflammatory hyperpigmentation related to photoaging and may be more susceptible to side effects from dermatologic treatments, including laser resurfacing.⁷ Accordingly, this study adds to the existing literature by evaluating the effectiveness and safety of nonablative fractional diode laser combination wavelength treatment (1440-nm and 1927-nm handpieces) in participants with Fitzpatrick skin types I to V and mild-to-moderate photoaging. Significant improvements were observed in parameters of photodamage, including rhytides, skin texture, dyschromia/pigmentation, skin radiance, and pore size, at 1 and 3 months after the final treatment. In addition, the procedure had substantial participant satisfaction and a favorable safety profile. These parameters were selected because they represent signs of photoaging,^8,9 and resolution of these features is often the goal for patients undergoing skin resurfacing.⁹

Nonablative laser combination wavelength treatment was designed to address the limitations of traditional ablative lasers by utilizing fractional photothermolysis to rejuvenate and resurface the skin while sparing surrounding tissues.³ Nonablative fractional lasers create “microislands” of thermal injury (microthermal treatment zone) that spare surrounding tissues without removing the epidermis and provide therapeutic effects.^3,10–12 As such, by treating only a percentage of the affected area and using a specific density of microscopic lesions, fractional photothermolysis produces less total tissue damage and downtime.^3,11,12 Thermal damage to the stratum corneum is further reduced by using midinfrared wavelengths (1320–1927 nm), which target water as a chromophore.³ Compared with the 1440-nm handpiece, the 1927-nm wavelength confers a higher absorption coefficient for water, resulting in wider, shallower microthermal treatment zones and preservation of the stratum corneum.³

As a class, nonablative lasers generally produce a few thermal side effects, but choice of system, wavelength, and settings will dictate efficacy and safety outcomes.¹³ For instance, through a single handpiece, the nonablative, fractionated 1550-nm erbium-doped glass/1927-nm thulium laser system offers higher power, greater density, and more variable energy settings than the 1440-nm/1927-nm diode laser system described here.^3,13 With its ability to produce a broader selection of spot sizes and higher densities, the 1550-nm erbium-doped glass/1927-nm thulium laser system addresses a wider range of skin concerns with more effective results and longer downtime. Comparatively, the 1440-nm/1927-nm diode laser system is less disruptive to the stratum corneum and epidermis and is designed to address milder skin concerns with a lower peak power and depth range. These reduced thermal effects are particularly beneficial for patients with darker skin types or skin conditions that require less thermal damage, such as postinflammatory hyperpigmentation and melasma.¹³ In this study, treatment with the 1440-nm/1927-nm diode laser system was well tolerated, with no serious adverse events and noticeable reductions in erythema and edema. No dryness/flakiness, hypopigmentation, hyperpigmentation, blistering, or scarring occurred during or after treatment. Thus, nonablative fractional diode lasers may be preferred by both practitioners and patients because of their convenience and safety.

Patient satisfaction is the predominant factor in determining the success of a cosmetic intervention.¹⁴ In this study, participant self-assessment revealed a positive perception of overall appearance at 3 months post-treatment, with most (96.4%) expressing satisfaction with the treatment outcome. These findings support previous reports of high patient satisfaction with the 1440-nm and 1927-nm handpieces. For instance, in a study of 78 participants with diverse skin types and mild-to-moderate photodamage and/or dyspigmentation, 86% of participants reported satisfaction 2 weeks after treatment with the 1927-nm wavelength handpiece in combination with topical serum.¹⁵ Another study of 40 women treated with the 1927-nm wavelength handpiece reported ongoing post-treatment satisfaction through 12 weeks.⁴ In addition, a study of 32 participants with Fitzpatrick skin types III and IV who had rosacea and acne scars treated with the 1440-nm wavelength handpiece found that 73.3% were satisfied or highly satisfied after 3 treatments and that overall satisfaction was high (average score of 3.8 on a 1–5 scale).¹⁶ In another study of the 1440-nm handpiece across diverse skin types, participant satisfaction was high (average score of 4.3 on a 1–5 scale) and was significantly associated with improvement in overall facial appearance.¹⁷

Because epidermal melanin behaves as a chromophore, patients with diverse skin types require modifications to laser parameters when undergoing resurfacing procedures, such as lower treatment densities.¹⁸ Historically, patients with photoaged darker skin types present with pigmentation-related challenges, including melasma and postinflammatory hyperpigmentation, and have been shown to be more susceptible to side effects from high-powered resurfacing treatments, including postprocedural hyperpigmentation or hypopigmentation.^7,18 Because nonablative fractional lasers target water molecules, not melanin, they spare epidermal melanin and result in improved safety and less pigmentary abnormalities for patients with darker Fitzpatrick skin types compared with ablative treatment.³ In this study, which comprised nearly 30% Fitzpatrick skin types IV or V, no adverse effects typically associated with darker skin types (e.g., pigmentation changes) occurred during or after treatment. Coupled with high patient satisfaction, these findings support the use of fractional diode lasers in an expanded patient population compared with historical (e.g., ablative) options.

Limitations of this study include a small participant population (N = 28) and lack of a control arm. Future studies should enroll a broader range of participants, including those with severe photoaging and an equal proportion of Fitzpatrick skin types, to assess the generalizability and effectiveness of nonablative laser treatment system in diverse populations, which could contribute to a more comprehensive understanding of its applications in clinical practice. Further research should also implement photonumeric scales to grade specific manifestations of photoaging in diverse skin types. In addition, studies should establish standard treatment protocols (e.g., number of sessions and intervals between treatments) to help clinicians achieve optimal outcomes in patients with photoaged skin. While not included in this study, concomitant topical regimens may enhance rejuvenation outcomes and should be explored in this patient population.

Despite these limitations, this study supports the effectiveness of nonablative fractional diode laser combination wavelength treatment (1440-nm and 1927-nm handpieces) for the treatment of mild-to-moderate photoaged skin and across diverse skin types. The post-treatment resolution of erythema and edema suggests reduced downtime, and participants reported high rates of satisfaction after treatment. Taken together, these results add to a growing literature that supports the effectiveness and safety of combination skin resurfacing treatment regimens featuring nonablative fractional lasers across skin types and in photoaged skin. Clinicians may use this evidence to inform treatment decisions for patients with mild-to-moderate photoaged skin, including those with darker Fitzpatrick skin types.

Supplementary Material

ds-51-52-s001.docx ^{(1.8MB, docx)}