Treatment of periorbital aging with negative pressure fractional microneedle radiofrequency: A self‐controlled clinical trial

Several treatment modalities are used for the treatment of periorbital rejuvenation with variable results. Recent studies showed that fractional radiofrequency may be an effective treatment modality for periorbital aging. This study aims to determine the efficacy and safety of negative pressure fractional microneedle radiofrequency (NPFMR) as a treatment for periorbital aging.


| INTRODUC TI ON
The first signs of aging are in the periorbital area, where laxity of the orbital septum, herniation of orbital fat, and loss of subcutaneous collagen lead to a series of manifestations such as eyelid bags, periorbital skin laxity, and wrinkles. 1,2The degree of aging depends on internal factors such as genetics, skin type, and external factors such as sun exposure, smoking, environment, and nutritional status. 3 Because of its special anatomy, treatment of periorbital aging is extremely challenging.
Currently, there exists a variety of periorbital antiaging methods, encompassing topical medications, chemical peels, lasers, fat fillers, injections, and surgical interventions, among others.5][6] Therefore, it is crucial to explore a treatment modality that produces positive results while mitigating potential risks.
In 2009, Hantash BM et al. 7 first used bipolar fractional microneedle radiofrequency (FMR) to heat the dermal tissue, which, by regulating the pulse width and precisely controlling the temperature, promoted the initiation of healing mechanisms as well as fiber remodeling in the dermal tissue, confirming that bipolar fractional radiofrequency microneedle not only tightened the deep dermal structures but also minimized epidermal damage.In 2010, Alexiades-Armenakas M et al. 8 compared the effectiveness of minimally invasive fractional radiofrequency with surgery for improving facial skin laxity in a randomized double-blind trial and found that a single fractional radiofrequency microneedle treatment could improve laxity up to 37% of surgical treatment.This suggests that minimally invasive fractional radiofrequency treatment offers an important nonsurgical option for facial rejuvenation.In recent decade, the application of FMR technology in cosmetic medicine has been more and more popular.
The FMR can be divided into insulated and non-insulated according to whether the needle body is insulated or not.The body of the microneedles is wrapped by an insulating material, and the energy is only released at the tip of the microneedles, which is accurately delivered to the target tissue, resulting in powerful thermal stimulation with less damage to the epidermis.Non-insulated microneedles transfer energy along the entire needle body, and the radiofrequency heating area is significantly larger than that of insulated microneedles, resulting in better clinical efficacy.However, a larger heated area may cause epidermal damage, leading to a higher risk of pigmentation, and prolonged downtime. 9,10R is categorized into negative and nonnegative pressure based on the presence or absence of a negative pressure device in the therapeutic hand.2][13][14][15] However, ocular region and areas with loose skin tissue, such as the neck, axilla and abdomen, nonnegative pressure FMR treatment is prone to eye injury and potential complications in the relaxed area, such as excessive compression of the thyroid gland in the neck, scar after burn, etc.The negative pressure technology can solve these problems well.With the help of intelligent negative pressure technology, NPFMR can make the adsorbed skin completely on the same plane, precisely control the depth.The needle can be automatically discharged only after the negative pressure detection reaches the standard after the treatment head is completely attached to the skin.There is no obvious pressure on the treatment area, and the treatment is more relaxed, safe and comfortable, and the related risks are smaller than those of previous radiofrequency devices.
The objective of this study was to assess the efficacy and safety of NPFMR to treat periorbital aging.

| Methods
Twenty-five patients were treated two times with an interval of Operational process: Before treatment, the face is routinely cleaned efficacy analysis, negative pressure fractional microneedle radiofrequency, periorbital rejuvenation, safety evaluation and compound lidocaine cream is applied for about 1 h.After the above operations are completed, the treatment head is routinely installed and the treatment parameters are adjusted.The treatment operation is carried out in a tight, seamless, carpet-like manner, with an overlap rate of approximately 50% and 300 rounds to avoid missing as much as possible.If necessary, local intensive treatment can be carried out for the obvious relaxation area immediately after the operation, levofloxacin hydrochloride eye gel is applied to the treatment place, and a sterile restorative eye mask is applied after the treatment.Tell the patient to moisturize and protect themselves from the sun on a daily basis, and the second treatment will be performed after 1 month.

| Efficacy evaluations
A researcher who did not participate in the treatment evaluated before treatment and 1, 3, and 6 months after the final treatment.
The VISIA (Canfield Imaging Systems, CANFIELD Technologies Inc.) skin tester detects periorbital wrinkles; the multifunctional test platform MPA10 (Multi Probe Adapter, CK Co., Germany) system connection probes include: Skin-Glossymeter GL200, Mexameter MX18, Corneometer CM825, Tewameter TM300, Skin-pH-Meter PH905, which can respectively detect gloss, melanin, hydration, TEWL and pH value; skin ultrasound (KOLO, Kona Medical Technology Co., Ltd.) detects the dermal thickness of periorbital skin.Three repeated measurements were made on both sides of the periorbital area (at 1 cm from the outer canthus) and the average value of the measured values was used as the index in the analysis.

| Histologic biopsy analysis
A biopsy sample was taken with surgical excision before and after treatment.To ensure as much homogeneity as possible, we selected the skin tissues of the symmetrical parts of the eyebrows on both sides as biopsy samples.Samples were fixed by 10% formalin, sliced, and images were collected.All tissues were first observed at 10×, and then three nonoverlapping areas were randomly selected to acquire 40× images, and the percentage of positive area was calculated for each image, and the results were averaged.HE staining was used to assess dermal collagen proliferation, immunohistochemical staining to assess the expression of type I and type III collagen fibers in the dermis as well as EVG staining to assess the expression of elastin fibers.

| Safety assessments
After each treatment, patients were recorded for any significant adverse reactions, such as edema, bleeding, crusting, pigmentation, etc. Visual analogue scale (VAS) was used to evaluate the pain degree of therapy (0 point: no pain, 1-3 points: mild pain; 4-6 points: moderate pain; 7-10 points: intense pain).

| RE SULTS
Of the 25 subjects enrolled, 22 completed the study.Ten patients had Fitzpatrick skin type III and 12 patients had type IV.The mean age was (47.73 ± 8.06) years with a range of 35-62 years (Table 1).
One subject dropped out due to pain during NPFMR treatment after the first session, and two patients did not complete the follow-up.
Photographs obtained by the VISIA system at baseline and after the therapy are shown in Figure 1.Wrinkles identified by VISIA decreased significantly at 6 months after treatment compared with before treatment.
Different instruments were used to detect various indicators of periorbital skin.The results showed that wrinkle count decreased (p < 0.05), the skin gloss and dermal thickness increased (p < 0.05), and there were no significant differences in hydration, TEWL, melanin, and pH at 1 month after treatment compared with before treatment.At 3 months after treatment, the wrinkle count and TEWL were decreased (p < 0.05), the hydration, pH and dermal thickness value were increased (p < 0.05), the skin gloss was restored to the level before treatment, and there was no significant difference in melanin.At 6 months after treatment, wrinkle count and TEWL continued to decrease (p < 0.05), while the hydration, TA B L E 1 Clinical characteristics of the 22 patients who completed the study.pH and dermal thickness continued to increase (p < 0.05).There was no significant difference in melanin compared with that before treatment (Table 2).
Histopathological evaluation of a 48-year-old male patient with Fitzpatrick type IV.HE staining showed that before treatment, the arrangement of collagen fibers in the dermis was disordered, the collagen bundles were short, curly, broken, and the density distribution was uneven.One month after treatment, it was seen that the collagen fibers were arranged in a rod shape, with a significantly increased number, a significantly smaller collagen fiber gap and a more neat collagen arrangement.At 3 months and 6 months after treatment, the collagen fibers in the dermis were arranged in a wavy shape, neat and orderly, with a more uniform distribution (Figure 2).
Immunohistochemical staining results showed that the expression levels of type I and III collagen fibers (9.84%, 10.84%, respectively) at 1 month after treatment were higher than those before treatment (7.39%, 9.32%, respectively).At 3 and 6 months after treatment, the expression level of type I collagen fibers (11.86%, 16.35%, respectively) continued to increase, while the expression level of type III collagen fibers (6.33%, 8.96%, respectively) decreased and was lower than the level before treatment (Figures 3,4).EVG staining results showed that the expression level of elastic fibers at 1, 3, and 6 months after treatment (14.63%, 23.91%, 26.64%, respectively) was higher than that before treatment (10.09%).Moreover, it continued to increase in 3 and 6 months after treatment compared with 1 month after treatment (Figure 5).
The pain during the treatment was tolerable, the VAS score was

| DISCUSS ION
The periorbital area is one of the earliest regions affected by aging that is mainly related to genetics and long-term UV exposure.
Periorbital aging is mainly characterized by periorbital wrinkles, upper eyelid laxity and pigment accumulation, which have negative  Abbreviations: M, month; ITA, individual type angle, representative melanin.a Indicated that 1, 3 and 6 months after treatment were respectively compared with baseline, p < 0.05.
b Indicated that 3 and 6 months after treatment were respectively compared with 1 month after treatment, p < 0.05.
c Indicated the comparison between 6 months after treatment and 3 months after treatment, p < 0.05.
| 1273 effects on the aesthetic and mental health of patients, for which there are various treatment options.
NPFMR is a new type of treatment device that combines fractional mode, microneedle stimulation and radiofrequency technology under the effect of negative pressure attraction.This technique, using insulated or noninsulated microneedles that penetrate the skin and emit radiofrequency energy, stimulates collagen denaturation, contraction, and fibroblast proliferation. 11,16Because the surface of the microneedle is plated with gold, it is also known as "gold microneedle radiofrequency" or "gold microneedle".Different from traditional radio frequency, FMR has the dual effects of mechanical damage of microneedle and radiofrequency heat transmission, and when it acts through the epidermis to the deep dermis, most of the energy is retained during transmission, reducing the risk of burning the epidermis and reducing the occurrence of adverse reactions such as post-operative erythema and hyperpigmentation.
In our study, different instruments were used to noninvasively detect various indicators of periorbital skin.Wrinkle count identified by VISIA system showed a continuous trend of reduction after treatment, which confirmed the significant and long-lasting effect of NPFMR in wrinkle removal.Healthy skin barriers are characterized by relatively high skin hydration levels and low water loss. 17 thereby promoting the recovery of skin elasticity, increasing skin moisture, and reducing skin water loss.The hydration of periorbital skin continued to increase and the TEWL continued to decrease after treatment in this study, from which it can be inferred that the skin barrier was healthier after NPFMR treatment.Although the pH was elevated, it remained within the normal range.In addition, there was no significant change in melanin before and after treatment, confirming that the treatment is safe for dark-skinned people.
Meanwhile, our study concluded that the periorbital dermal thickness was significantly thickened after NPFMR treatment.
To enhance the objectivity of the results, histological analysis of the periorbital skin of one patient was obtained for this study.It has been shown that the collagen content of the dermis increased by 7.9% after radiofrequency treatment compared with the non-treated side. 18Similarly, enhanced fibroblast activity, new collagen production, and dermal thickening have been shown in animal studies in hairless mice. 19Previous studies have confirmed that radiofrequency causes a collagen remodeling process in the dermis of the skin lasting 4-6 months through collagen denaturation, contraction and stimulation of fibroblasts. 20Consistent with this report, in our study, it was found by HE staining that the number of collagen fibers in the dermis increased at 1, 3, and 6 months after NPFMR, and the dermal collagen fibers were neatly arranged in a wavy pattern with uniform distribution.This indicates that negative pressure FMR can maintain  to the fact that radiofrequency energy reaches the dermis directly and is not absorbed by melanin.PIH was seen in a few participants with dark skin types treated with FMR. 23In our study, one subject developed reversible PIH after NPFMR treatment, and the pigmentation diminished after 1 month of topical medication.Considering that this subject has an underlying melasma and has been engaged in outdoor work for a long time after treatment without strict sun protection.Previous studies have shown that FMR can reduce the risk of PIH while treating melasma, and it can also be used as a percutaneous drug delivery system for combination drug delivery therapy. 24,25It is worth noting that postoperative care such as moisturizing and sun protection are also an important factor affecting the efficacy.At the same time, some drugs, such as tranexamic acid and vitamin C, can be introduced to prevent hyperpigmentation when melasma patients use FMR to treat periorbital aging in the future. 26,27Noteworthy, the pain scores of the subjects in this study belong to moderate pain, which is tolerable, but the intraoperative pain is indeed a key problem to be solved, because it is an important factor in determining whether patients can cooperate with treatment.Tang et al. 28 pointed out in their study that FMR thus releases two to three times more energy at target tissues than traditional devices, resulting in much higher pain ratings in the RF-treated side compared with the non-ablative fractional laser-treated side.This also requires clinicians to think about how to relieve pain in future operation, such as oral acesodyne or by delivering ultrasound-guided anesthetic.
This study still has some limitations.On the one hand, the number of subjects is small and the follow-up time is only half a year.To further confirm the reliability of these results, a randomized trial with a larger sample size and a longer follow-up can be designed in the later stage.On the other hand, there is a lack of blank or positive control in this study.Although this limitation could be improved by a splitface study, ethically it is difficult to ask participants to be included in a study where half of their periorbital areas will be treated and the other half will receive placebo or another treatment, resulting in different outcomes on the same face.At present, there are few research reports on the treatment of periorbital aging with NPFMR, and more well-designed prospective studies are needed to further explore it, which is also the direction we need to work on in the future.

| CON CLUS IONS
NPFMR can significantly improve periorbital aging, reduce periorbital wrinkles, with high safety and low incidence of side effects, which is worthy of clinical promotion.
After passing the ethical review, 25 patients with periorbital aging were included as the research objects.The inclusion criteria included 35-65 years old, meeting the diagnosis of periorbital aging, with Wrinkles and laxity as the main symptoms.The exclusion criteria were: (1) Patients who had received periorbital aging therapy within 6 months prior to enrollment, such as laser, injection, and surgery; (2) Patients with traumatic periorbital lesions, infection, serious eye diseases or serious systemic diseases; (3) Scar diathesis patients; (4) Pregnant and lactating women.All subjects signed informed consent.

1
month.All patients were treated with NPFMR (high-frequency electrocautery, United II, Shenzhen Peninsula Medical Co.), The specific methods were as follows: (1) Periorbital treatment areas: The upper boundary is 2 cm above the eyebrow, the lower boundary is the line of the midpoint of the bilateral tragus, about level with the zygomatic arch, and the left and right borders are the bilateral temporal regions.The area was treated with MicroRF negative pressure handle.(2) Treatment parameters: Needle insertion to 1.1-1.5 mm depth, power 4-6 W, and duration 100-330 milliseconds.(3) SPSS 23.0, statistical software is used for analysis.All continuous data are tested for normality.When the data meet the normal distribution, they are expressed by mean ± SD (x±s) and analyzed by one-way repeated measures ANOVA; The data that do not conform to the normal distribution are expressed by quartile, the rank-sum test of paired design data are used; The difference was statistically significant (p < 0.05).

( 4 .
05 ± 1.26).Erythema disappears within 1 day, and complete recovery from edema within 2-3 days.One subject developed mild PIH after the first treatment due to lack of sun protection, and the hyperpigmentation diminished after 1 month of topical drugs.No obvious adverse reactions were observed in the rest.

F I G U R E 1
Treatment side VISIA images of typical patients (54-year-old female, Fitzpatrick skin type IV) at baseline (A, C) and 6 months after the second treatment (B, D).The green lines represent wrinkles identified by VISIA system.TA B L E 2 Comparison of periorbital skin indicators at different times.
FMR heats the dermal layer of the skin, stimulates the regeneration of collagen, and promotes the secretion of growth factors and cytokines, F I G U R E 2 HE staining biopsy specimens from the same patient, 40×.(A) Baseline; (B) 1 month after treatment; (C) 3 months after treatment; (D) 6 months after treatment.F I G U R E 3 Immunohistochemical staining biopsy specimens from the same patient, type I collagen fibers, 40×.(A) Baseline; (B) 1 month after treatment; (C) 3 months after treatment; (D) 6 months after treatment.

F I G U R E 4
Immunohistochemical staining biopsy specimens from the same patient, type III collagen fibers, 40×.(A) Baseline; (B) 1 month after treatment; (C) 3 months after treatment; (D) 6 months after treatment.F I G U R E 5 EVG staining biopsy specimens from the same patient, elastic fibers, 40×.(A) Baseline; (B) 1 month after treatment; (C) 3 months after treatment; (D) 6 months after treatment.long-term efficacy.Meanwhile, we observed that the collagen quantity in the dermis of periorbital skin before treatment was low, loosely arranged, and unevenly distributed, which is consistent with the clinical understanding of skin photoaging.Immunohistochemical staining and EVG staining showed a significant increase in the expression levels of type I collagen fibers and elastic fibers in the periorbital skin after NPFMR treatment, suggesting that collagen fibers were renewed and remodeled after NPFMR, and the increase of elastic fibers is an important factor in reducing wrinkles and improving skin texture.Differently, the expression level of type III collagen fibers in this study increased in the early stage and showed a decreasing trend in the later stage, probably because dermal collagen fiber remodeling is a process that occurs over time and biopsies at different times may show different stages of remodeling.