Periorbital Skin Rejuvenation of Asian Skin Using Microneedle Fractional Radiofrequency

Abstract

Background

The periorbital area plays an important role cosmetically. Periorbital wrinkles are attributed to long-term, repeated use of orbicularis oris muscles and UV-induced dermal collagen degeneration. Fractional microneedle radiofrequency (RF) treats scars and laxity by creating vertical channels of injury in the dermis, triggering a scarless healing cascade and neocollagenesis.

Objective

To evaluate the effect and safety of a novel fractional microneedle RF device on periorbital wrinkles based on several objective indicators.

Methods

Eleven healthy Korean patients aged 30 to 75 years with periorbital wrinkles were included in this study. Wrinkle grades were evaluated using the Fitzpatrick wrinkle assessment scale (WAS). The melanin and erythema index, transepidermal water loss (TEWL), and three parameters for elasticity were recorded. Skin biopsies were obtained in patients who consented.

Results

All patients exhibited wrinkle improvement in the lateral periorbital area, and two patients also showed efficacy in the lower eyelid area. There was a statistically significant decrease in WAS and a significant improvement in the melanin index of V4 and V5. TEWL also showed a considerable decline on V4 and V5, suggesting that the water content of the skin increased with repeated laser sessions. A peak increase in viscoelasticity and a decrease in retraction time following the first laser application were observed. In the histopathologic examination, the dermis had a denser collagen and elastin content.

Conclusion

Microneedle fractional RF resulted in statistically significant long-term clinical improvement of periorbital wrinkles and enhanced pigmentation and skin hydration.

INTRODUCTION

The periorbital area plays an important role cosmetically because it contributes to initial first impressions of the individual and easy recognition of facial aging¹. Periorbital wrinkles are attributed to long-term, repeated use of orbicularis oris muscles and UV-induced dermal collagen degeneration. Thus, various treatments for periorbital rejuvenation have been introduced, such as surgical lifting, chemical peeling, botulinum toxin, filler injection, and laser treatment²,³,⁴,⁵.

Fractional microneedle radiofrequency (RF) is a percutaneous collagen induction therapy used to treat scars and laxity. The needling device creates vertical channels of injury in the dermis, triggering a scarless healing cascade and neocollagenesis¹. This prospective study evaluated the effect and safety of a novel fractional microneedle RF device on periorbital wrinkles based on several objective indicators.

MATERIALS AND METHODS

Study population

The study included 11 healthy Korean patients aged 30 to 75 years with periorbital wrinkles. Patients with a history of injection with collagen, fat, hyaluronic acid, botulinum toxin, chemical peel, lifting surgery, and nonablative and ablative skin resurfacing laser treatments within three months were excluded. Patients with infectious or inflammatory skin disease, keloid formation, or chronic disease were excluded. All patients were informed of the study objectives, process, benefits, and possible complications, and written consent was obtained before treatment. This study was approved by the institutional review board of Korea University Hospital (2020AS0014).

Treatment protocols

Each patient received microneedle RF therapy on both periorbital areas, including the lower eyelid, temple, and eyebrow area. A fractional microneedle RF (GENIUS^®; Lutronic) device delivers bipolar RF energy into the dermis using a thin rectangular-shaped tip (P14D) consisting of 2 columns and seven rows, including a total of 14 microelectrodes. This device used renovated RF with real-time impedance feedback to facilitate the clinical measurement of energy delivered during each pass. Also, the monitoring system can dynamically calculate the total energy delivered to the skin, suggesting a reasonable and objective treatment endpoint.

The treatment was performed in three sessions at 4-week intervals: baseline (V1), week 4 (V2), and week 8 (V3). The additional visits were made at week 12 (V4) and six months after the final treatment (V5) to evluate the lon-term effects of the microneedle RF. Before every procedure, a topical anesthesia cream (A mixture of Lidocaine 2.5% and Prilocaine 2.5%; Tai Guk Pharm., Seoul, Korea) was applied over the periorbital area. The treatment area was cleansed and thoroughly dried. The procedure was performed at a depth of 1.8 mm with a 60 mJ/pin energy in two passes. A cumulative energy of 100 J was applied on each side of the periorbital area.

Outcome assessments

At every visit (baseline [V1], four weeks [V2], eight weeks [V3], twelve weeks [V4], and six months after the final session [V5]), three-dimensional photographs of both sides of the periorbital areas were acquired under identical settings. Wrinkle grades were evaluated by two well-trained dermatologists who did not participate in the treatment, using the Fitzpatrick wrinkle assessment scale (WAS) based on scores ranging from 1 to 9⁶.

Dermalab combo (Coretex^®) was used to measure skin color, water content, and elasticity. The melanin and erythema index, transepidermal water loss (TEWL), and three parameters for elasticity were recorded. Air pressure adjusted to 150 mbar (soft) for 1.0 mm skin thickness was applied three times at a distance of 1.5 cm lateral to the eye, and the average value was measured as elasticity. During the final long-term follow-up, patients were asked to rate their overall satisfaction on each side and to report any side effects. The satisfaction scale was as follows: 1=not satisfied, 2=slightly satisfied, 3=satisfied, and 4=very satisfied.

Additionally, skin biopsies using a 2-mm-sized punch were obtained before and after three laser sessions only in patients who consented. Hematoxylin-eosin staining, Masson trichrome (M-T) staining, and elastin staining were performed to compare the long-term histopathologic effects of microneedle RF.

Statistical analysis

Based on the initial visit, the Friedman test for repeated measures was performed to determine significant differences between the parameters documented at each session. Wilcoxon signed-rank test was performed to the statistical significance of the changes in the various indices. We used R version 4.1.1 (R Foundation for Statistical Computing) for statistical analysis. p-values of less than 0.05 were considered significant.

RESULTS

Patient demographics

Nine of the eleven subjects enrolled completed the study. Eight subjects were female (88.9%), and one was male (11.1%). The mean age was 48.1±13.1 years, with a range of 33 to 72 years. One subject dropped out due to pain during microneedle RF treatment after the second session, and one patient did not complete the follow-up. Six patients showed Fitzpatrick skin type III, and three had type IV (Table 1, Supplementary Fig. 1).

Table 1. Baseline characteristics of subjects of the study.

		Value (total no.=9)
Sex
	Male	1 (11.1)
	Female	8 (88.9)
Age (yr)		48.1±13.1 (33~72)
Fitzpatrick skin type
	III	6 (66.7)
	IV	3 (33.3)

Values are presented as number (%) or mean±standard deviation (range).

Clinical improvement

The degree of periorbital wrinkling was compared with the baseline at every visit and assessed according to Fitzpatrick’s WAS. Among the static periorbital wrinkles, the shallow ones were effectively treated with microneedle RF. All patients exhibited wrinkle improvement in the lateral periorbital area, and two patients also showed efficacy in the lower eyelid area. Representative clinical photographs are shown in Fig. 1. We received the patient’s consent form about publishing all photographic materials. Compared with the baseline, three sessions of needle RF showed clinical improvement in periorbital wrinkles. Significantly, shallow static wrinkles were reduced, and the festooned bag on the lower eyelid also decreased. Six months after the final session, patients showed significant periorbital rejuvenation, suggesting that the treatment efficacy of microneedle RF can be maintained long-term.

Fig. 1. Clinical improvement of periorbital wrinkles. Compared with the baseline (A, D), three sessions of needle radiofrequency (RF) showed clinical improvement of periorbital wrinkles (B, E). Significantly, shallow static wrinkles were reduced (E), and the festooned bag on the lower eyelid also decreased (B). Six months after the final session, patients showed significant periorbital rejuvenation (C, F), suggesting that the treatment efficacy of microneedle RF can be maintained long-term.

Paired comparison by the Friedman test for repeated measures and Wilcoxon signed-rank test showed a statistically significant decrease in WAS according to the laser treatment sessions (V3, 4, 5) (Fig. 2).

Fig. 2. Fitzpatrick wrinkle assessment scale (WAS) change during needle radiofrequency (RF) treatment. Compared with the baseline (V1), Fitzpatrick WAS decreased according to the needle RF treatment sessions, showing statistical significance at eight weeks (V3), 12 weeks (V4), and six months after the final session (V5). ^*Statistically significant (p<0.05).

Melanin and erythema index, TEWL, and elasticity

The average melanin index showed a rapid decrease after the first laser treatment and after long-term follow-up. When each session was compared with the baseline, there was a statistically significant improvement in the melanin index of V4 and V5 (p=0.027 and p=0.003). However, the erythema index did not show significant differences regardless of the number of laser treatments. TEWL also showed a significant decrease on V4 and V5 (p=0.009 and p=0.004), suggesting that the skin's water content increased with repeated laser sessions (Fig. 3).

Fig. 3. Changes in melanin, erythema index, and transepidermal water loss (TEWL) change according to needle radiofrequency (RF) sessions. Compared with the baseline (V1), melanin index and TEWL showed a statistically significant decrease at the last needle RF session (12 weeks, V4) and long-term follow-up visit (6 months, V5) (p=0.027, 0.003, and 0.009, 0.004 respectively). However, the erythema index did not show significant differences between the treatment sessions and long-term follow-up. ^*Statistically significant (p<0.05).

Elasticity parameters included retraction time (RT) and viscoelasticity (VE). Although there was a peak increase in VE and a decrease in RT following the first laser application, there was no statistical significance between the treatment sessions.

Patient satisfaction score and adverse events

There were no serious adverse events, and the pain score, according to the numeric rating scale (NRS), was an average of 5.33. One patient showed immediate erythema and wheals at the needle insertion site, which subsided in a day. Patient satisfaction varied: one very satisfied (4), five satisfied (3), and three slightly satisfied, averaging 2.78. All patients showed periorbital rejuvenation on the lateral area, and two patients reported additional effects on the lower eyelid area involving wrinkles and festooned eyebags (Fig. 1A~C).

Histopathologic examination

Two patients agreed with a skin biopsy. After three sessions of microneedle RF, the collagen content was denser in the dermis, especially around the sebaceous unit in the M-T stain. Elastin staining also showed denser elastin content in the dermis.

DISCUSSION

Treatment modalities for photoaged skin include ablative resurfacing, laser treatments, and surgical face-lifting. However, the periorbital area is especially sensitive with anatomical vulnerability and increased adverse events⁷. In this regard, minimally invasive microneedle RF for periorbital wrinkles represents a safe and effective treatment choice.

The microneedle RF system can penetrate the skin with microneedles and deliver thermal energy into the dermis. This physical stimulation induces wound healing of the dermal collagen contributing to its regeneration and remodeling, resulting in skin tightening and improved skin laxity, and fewer wrinkles⁸,⁹. The extremely thin microneedles and thermal coagulation limited to the tip of the electrode increase the effectiveness of dermal remodeling and rejuvenation, thereby avoiding unnecessary epidermal damage.

For optimal energy delivery, a few new microneedle RF devices have been recently introduced⁸,¹⁰. The device used in this study is an insulated fractional microneedle RF device with a real-time impedance feedback system. The RF generator produces smooth flat power to the tissue, and this intelligent feedback loop ensures that for each pulse at each layer of tissue, tissue coagulation is achieved at the most appropriate temperature. Additionally, with a feedback system of this type, the longer the energy can be delivered within this range, the larger the volumetric coagulation zone that can be created. This results in a tunable injury size, free from the risk of overheating and undesired tissue response around the electrodes.

The precise energy delivered through the needles is dynamically accumulated while using the device, allowing for the optimization of energy by the physician. This means consistency of energy delivery, leading to higher treatment efficacy. Not only is measuring but also knowing the amount of energy deposited per treatment. Therefore, it is a valuable tool for maintaining safety and consistency between treatments and patients, and no other RF needle device has this measurement or accuracy.

A review of the literature listed in the PubMed database revealed that some microneedle RF studies focused on periorbital wrinkles. Kim et al.¹¹ reported that fractionated microneedle RF (FRMF) was effective and safe for the treatment of periorbital wrinkles in 11 Korean female patients, especially showing long-term effects in a 3-month follow-up. Lee et al.² also showed the clinical efficacy of FRMF on periorbital wrinkles in 20 dark-skinned Korean patients. However, few studies measured the objective indicators of treatment outcome and long-term follow-up lasting more than three months.

In our study, skin rejuvenation in the periorbital area was assessed using the Fitzpatrick WAS and based on the melanin index, erythema index, TEWL, and elasticity index. All patients showed progressive improvement in Fitzpatrick WAS after microneedle RF application, showing a statistically significant decrease in wrinkle scale scores in subsequent sessions (Fig. 2). Further, the number of deep wrinkles decreased, and skin laxity of the intraorbital area also improved, as seen in Fig. 1. VE and RT showed peak improvement at V2 after the first laser treatment. However, the peak increase in VE and decrease in RT plateaued following repeated sessions. Despite clinical improvement, none of the elasticity-related indexes showed statistical significance (Fig. 4).

Fig. 4. Change in elasticity according to needle radiofrequency (RF) sessions. Both viscoelasticity (VE) and retraction time (RT) showed peak improvement in elasticity at eight weeks (V2), but the change was reversed eventually. Compared with the clinical improvement shown in Fig. 2 and 3, the objective indicators did not show statistical significance.

Interestingly, melanin index and TEWL were notably reduced in V4 and V5, which means that the pigmentation and water loss of periorbital skin were enhanced by microneedle RF (Fig. 3). Several studies using a combination of topical agents or other laser devices in patients with melasma were reported. A study by Cameli et al.¹² used monopolar RF and transdermal 1% kojic acid for the treatment of melasma patients. Kwon et al.¹³ investigated the efficacy of fractional RF combined with Q-switched Nd:YAG laser in melanosis. Both studies showed a reduction in melasma area and severity index. The present study showed that microneedle RF alone improved pigmentation and water content, an essential factor contributing to the perception of skin texture improvement and rejuvenation.

Additionally, this study involved a 6-month follow-up to evaluate the long-term effect of microneedle RF. The clinical photograph showed significant improvement in periorbital wrinkles and festooned infraorbital eye-bag, and the effect was maintained until the last visit (Fig. 1C, F). The values of Fitzpatrick WAS, melanin index, and TEWL were most reduced at V5, compared with previous visits (Fig. 3). This finding suggests the long-term effect of microneedle RF devices in skin rejuvenation. All patients were satisfied with the treatment without serious adverse events.

Previous studies reported the efficacy of RF devices for periorbital tissue tightening. Fitzpatrick et al.¹⁴ studied the 6-month progress of a nonablative RF device (0.25 or 1 cm² RF treatment tip). It showed a single treatment produced at least 1 point of improvement in Fitzpatrick wrinkle score and more tightening effects over 2 to 6 months by subsequent regeneration of new collagen. Biesman et al.¹⁵ reported eyelid tightening and reduction of hooding in 71% to 86% of subjects using a monopolar RF device (0.25 cm² treatment tip).

Those monopolar RF skin tightening methods, where the delivery electrode is placed over the target tissue and the return electrode is usually a sizeable rectangle-type electrode, inducing bulk heating and targeting a temperature level of 42℃ to 55℃. However, the RF device used in our study with the novel tissue-building approach, which uses a fractional tip, induces more optimal coagulation because the temperature of the dermal layer is raised to around 65℃ to 80℃ within milliseconds to seconds. A volumetric coagulation zone can be acquired at this ideal temperature range, inducing effective coagulation of protein denaturation and degradation, leading to neocollagenesis and neoelastogenesis. It could be the reason for better results at the 6-month follow-up of subjects. Additionally, by using the fractional tip, it might be possible to deliver thermal energy more evenly and deeply than the existing reported RF method.

A high-intensity focused ultrasound (HIFU) for noninvasive skin tightening device has also been used. One study¹⁶ showed that HIFU induces neocollagenesis in the deep reticular dermis level and shows heating availability comparable to RF. The RF device used in our study requires needling and insertion, unlike HIFU, which can potentially cause pain to patients due to mechanical damage. However, the advantage is that by performing needling, the heat energy can be delivered precisely to the controlled depth in the dermal layer of the skin desired by the operator.

Further, histologic evaluation in the tissue obtained by performing a two mm-sized punch on the periorbital area was done in this study. M-T and elastin staining after three treatment sessions showed denser collagen and elastin content in the dermal layer compared with the baseline (Fig. 5). Seo et al.¹⁷ reported similar results, including increased procollagen-1 and collagen content at four weeks after three sessions of microneedle RF. RF device is known to create thermal, biochemical, and mechanical effects to induce dermal remodeling and thereby increase collagen, elastin, and hyaluronic acid content to improve the elastic properties of the skin. Also, controlled thermal injury can cause neocollagenesis and neoelastogenesis, which this study confirmed via histologic analysis using a special stain¹⁸.

Fig. 5. Histologic changes of baseline and long-term follow-up on the periorbital area. (A) H&E stain and Masson trichrome stain before treatment and (B) elastin staining before treatment (baseline histology). (C) H&E stain and Masson trichrome stain after treatment and (D) elastin staining after treatment (200× magnified images). After three needle radiofrequency (RF) sessions, notably denser collagen and elastin staining in a dermal layer is consistent with neocollagenesis and neoelastogenesis reported in previous studies.

The study limitation relates to the small sample of the population investigated. Since the periorbital area is a sensitive structure with an important function, the patients were more concerned about study enrollment. Also, pain during the procedure was minimized by applying topical anesthetic cream, yet yielding a pain NRS score of 5.33 out of 10. Thus, another attempt is required, such as prolonged topical anesthesia under the occlusion or nerve blocks during the treatment.

In conclusion, fractional microneedle RF is effective for periorbital skin rejuvenation in Asian patients with darker skin types. The treatment resulted in statistically significant long-term clinical improvement of wrinkles and enhanced pigmentation and skin hydration. Further studies with a bigger population and diverse treatment parameters are necessary to validate the various applications of microneedle RF treatment.

DATA SHARING STATEMENT

The data that support the findings of this study are available from the corresponding author upon reasonable request.

SUPPLEMENTARY MATERIALS

Supplementary data can be found via http://anndermatol.org/src/sm/ad-22-217-s001.pdf.

Supplementary Fig. 1

Flowchart of the study.