Clinical application of radiofrequency technology in the treatment of facial skin wrinkles and laxity

Abstract

BACKGROUND

Aging is an inevitable aspect of human life, characterized by the gradual decline in the function of individual cells and structural components, including bones, muscles, and ligaments.

AIM

To evaluate the clinical effects of radiofrequency technology in treating facial skin wrinkles and laxity.

METHODS

This study included 60 female patients, aged 36-58 years (mean age 47.71 ± 1.56 years), who received focused radiofrequency technology treatment for facial wrinkles and laxity in the Department of Medical Cosmetology at our hospital between January 2021 and June 2022. Each patient underwent three treatment sessions, one every two months. Facial photographs were taken before treatment and one week after the final session. A single physician assessed wrinkle severity using a standardized wrinkle severity scale, and patients completed a satisfaction questionnaire one week after the last treatment.

RESULTS

After three consecutive radiofrequency treatments, performed every two months, patients exhibited significantly reduced wrinkles and skin laxity compared to baseline. One week after the third treatment, the mean facial wrinkle severity score had significantly decreased from 3.00 ± 0.79 to 2.71 ± 0.47 (t = 2.58, P < 0.05). Additionally, 88.24% of patients reported noticeable improvements in facial wrinkles and skin laxity. No serious adverse reactions occurred during or following treatment.

CONCLUSION

Radiofrequency technology demonstrates significant clinical efficacy in improving facial skin wrinkles and laxity.

Key Words: Focusing radio frequency; Facial wrinkles; Loose face; The curative effect; Radiofrequency technology

Core Tip: Radiofrequency technology has a remarkable clinical effect on the improvement of facial skin wrinkles and relaxation. To assess clinical efficacy of radiofrequency for facial wrinkles/laxity, 60 female patients received three focused radiofrequency treatments for facial aging at a medical cosmetology department. Post-treatment, the mean facial wrinkle severity score decreased significantly. 88.24% of patients reported noticeable improvements. No serious adverse events occurred.

INTRODUCTION

Aging is an inevitable aspect of human life, characterized by the gradual decline in the function of individual cells and structural components, including bones, muscles, and ligaments. These changes are particularly prominent in the face. The skin undergoes both intrinsic and extrinsic aging, leading to relaxation, fine lines, rough texture, pigmentation, telangiectasia, and other visible alterations[1]. The pursuit of immortality and eternal youth has fascinated humanity for centuries across various cultures. As medical advancements extend human lifespan, the demand for understanding the aging process and developing technologies to mitigate its effects has surged, with facial skin laxity becoming a focal point of research.

Facial lifting techniques are primarily categorized into surgical and non-surgical methods. Surgical facelifts, aimed at rejuvenating the face by addressing wrinkles, laxity, and muscle atrophy, originated in the early 20^th century. The first generation of these procedures involved local skin excision and suturing. The 1970s saw the introduction of the second generation, which focused on the superficial musculo-aponeurotic system (SMAS). In 1974, Skoog pioneered a method that separated the superficial fascia layer of the face and neck, later known as the SMAS technique[2]. By treating the skin and SMAS as a cohesive unit, significant improvements in the contour of the cheeks and neck were achieved. However, deeper anatomical interventions often resulted in increased complications, limiting the early adoption of SMAS techniques. In 1979, Tessier proposed subperiosteal facelift techniques, advocating for a deeper and safer approach that became known as the third generation of facelifts[3]. Subsequent developments by researchers, including Hamra[4] in 1992, advanced compound facelift techniques that addressed deeper layers, including the zygomatic pad and platysma muscle.

Traditional facelift surgeries can be traumatic, leading to a shift toward “minimally invasive” methods aimed at reducing incision length and scarring. Over the past decade, advancements in medical science and a deeper understanding of facial anatomy have led to the emergence of techniques such as endoscopic facelifts, double-plane facelifts, and small-incision facelifts[5]. The use of linear materials in facelifts has fundamentally transformed traditional approaches, yielding remarkable results, particularly in the lower face[6]. While surgical facelifts can significantly alter the condition of muscles, fascia, and deep tissues, their application must be carefully regulated, typically targeting patients aged 40 to 60. It is important to note that surgery cannot halt the aging process; skin laxity will reoccur with time, and repeated surgeries may cause more harm than benefit. In addition to surgical options, non-surgical treatments - including botulinum toxin injections, soft tissue fillers, lasers, radiofrequency, and focused ultrasound - are gaining prominence. These non-invasive methods are increasingly favored due to their high operability, minimal complications, and patient acceptance[7].

Radiofrequency technology, which operates within a frequency range of 3 kHz to 300 GHz, utilizes principles of induction, electrolysis, and thermal effects. In clinical settings, radiofrequency devices transfer electromagnetic waves that generate heat energy through charged particle collisions, effectively damaging or shrinking target tissues. The micro-thermal damage induced by radiofrequency in the skin and subcutaneous layers can upregulate factors such as transforming growth factor-β and matrix metalloproteinases, leading to both immediate inflammatory responses and long-term collagen proliferation[8,9]. This selective electrothermal effect is crucial for facial rejuvenation and the treatment of conditions like scars and stretch marks. Various radiofrequency devices, including monopolar, bipolar, and multipolar systems, each present unique advantages and drawbacks. Recently developed focused radiofrequency technology offers improved precision, concentrated energy delivery, reduced downtime, and enhanced patient experience.

Radiofrequency therapy has gained popularity for addressing skin laxity by stimulating collagen contraction and regeneration through thermal effects[10]. The high-frequency energy travels through normal soft tissue, generating heat at the positive electrode without raising its temperature, which facilitates its widespread application in cosmetic procedures for skin tightening, body shaping, and the treatment of conditions like atrophic scars, enlarged pores, and acne. Research has indicated that radiofrequency can also decrease fat cell volume by promoting the breakdown of triglycerides into glycerol and free fatty acids in the subcutaneous fat layer, thus improving facial contours[11]. ThermaCool TC radiofrequency, a monopolar radiofrequency device, was the first Food and Drug Administration-approved treatment for skin laxity and wrinkles. The rapid evolution of radiofrequency technology has solidified its role in skin laxity treatment, progressing from earlier single and bipolar devices to the current advanced multipolar systems, including minimally invasive options. Recent studies suggest that combining various cosmetic treatments is a growing trend in facial rejuvenation[12].

The platysma muscle, originating from the deltoid and pectoralis major fascia and inserting at the lower mandible, plays a significant role in facial ptosis. Its contraction, innervated by the facial nerve, contributes to downward skin movement and neck line formation. Radiofrequency therapy can relax the platysma muscle, enhancing the effectiveness of lifting muscles and facilitating an upward pull on the lower face. Furthermore, radiofrequency not only contracts collagen fibers but also stimulates fibroblast proliferation through thermal damage to the dermis, enhancing collagen synthesis and reorganization. This treatment can also lead to partial fat ablation, improving fat accumulation and contouring of the mandible. Given that the effects of single radiofrequency therapy can be limited, our study employed three consecutive sessions to enhance treatment outcomes. We statistically analyzed the clinical effects of radiofrequency on facial wrinkles and laxity, providing valuable insights for clinical practice.

MATERIALS AND METHODS

Clinical data

Sixty female patients aged 36 to 58 years (mean age 47.71 ± 1.56) were selected to undergo comprehensive radiofrequency-focused treatment for facial wrinkles and laxity at the Department of Medical Beauty in our hospital from January 2021 to June 2022. Patients were classified as having skin types III to IV according to the Fitzpatrick scale. All participants exhibited facial signs of aging, including forehead wrinkles, periorbital wrinkles, nasolabial folds, perioral wrinkles, and facial laxity. None of the patients had received facial treatments involving hyaluronic acid, collagen injections, autologous fat injections, laser therapy, intense pulsed light therapy, or radiofrequency therapy within six months prior to treatment. Additionally, they had not taken oral estrogen, retinoic acid, or collagen supplements in the three months preceding the treatment.

Inclusion and exclusion criteria

The inclusion criteria were as followed: (1) Clinical skin examination confirmed the presence of skin laxity and fine wrinkles; (2) Patients had not undergone any surgical or non-surgical facial treatments; (3) No metallic implants were present in the treatment area; and (4) Patients were able to cooperate voluntarily with follow-up and regular reviews post-discharge. The exclusion criteria were as followed: (1) History of treatment with pacemakers or other electronic devices; (2) Significant liver or kidney dysfunction, or complications from other serious conditions such as myocardial infarction; (3) Severe allergic constitution or tendency to develop keloids; (4) Patients with wasting diseases, such as tumors, currently using glucocorticoids or cytotoxic drugs; (5) Severe mental illness or cognitive dysfunction; (6) Patients unwilling to participate in the study; (7) Pregnant and lactating women; (8) Thyroid disease; (9) Individuals with other hereditary diseases; and (10) Poor skin condition, accompanied by existing skin diseases.

Treatment methods

The treatment was as followed: (1) Prior to treatment, contact lenses and any metallic items were removed; (2) Treatment equipment: Alma Lasers Ltd., Thermolift 2.0; (3) Treatment system: Accent XL system; and (4) Therapeutic method: Patients received three radiofrequency treatments, each approximately one hour long, with intervals of two months. The UniLarge Tune Face was utilized, with treatment depths set as follows: Level 1 at 4.5 mm; level 2 at 3.5 mm; level 3 at 2.5 mm; level 4 at 1.5 mm.

Treatment approaches based on facial aging types

Low facial fat drooping type: Treatment targeted the cheeks and jaw, with enhancement areas including the anterior tragus, mouth corners, and nasolabial folds. Three lifting lines were established: Upper (starting from deep nasolabial folds along the zygomatic bone to the anterior tragus), middle (from the oral fat sac to the anterior middle tragus), and lower (from the supporting ligament of the jaw along the mandible to beside the earlobe). Three levels of treatment were applied to the treatment area, with two levels in the enhancement area, using low negative pressure and eight overlapping treatments.

Middle and lower facial fat accumulation type: The treatment covered the cheeks, mandible, and submandibular area, with enhancement areas in front of the tragus and at the corners of the mouth. Three lifting lines and one compaction line (starting at the chin and ending at the mandibular angle) were utilized. The treatment area was set to the second treatment level, while the enhancement area was set to the first level, also using low negative pressure.

Therapeutic parameters: The therapeutic power was consistently set at 300 W, with therapeutic energy adjusted by modifying the “On” time between 0.6 to 1.5 seconds, tailored to the patient’s subjective comfort and tolerance levels. Treatment was deemed effective when the skin surface temperature was maintained at 41-42 °C for 1.5 seconds during the “Off” time. The initial energy selection involved starting with a lower time (0.6-0.8 seconds) for the first one or two holistic treatments to help patients acclimate to the radiofrequency heating sensation. The heating time was then gradually extended to reach the desired treatment temperature.

Post-treatment care: Patients were advised to maintain routine moisturizing and sun protection, with a focus on hydration in the two weeks following treatment. Follow-up observations were scheduled monthly for a total of three sessions, with a three-month post-treatment assessment. Patients were also instructed to consult a medical professional regarding the timing of any additional cosmetic procedures, and no special lifestyle or skincare modifications were required during the treatment period.

Efficacy evaluation and criteria

Facial photographs were taken before treatment and one week after the final session. A wrinkle severity rating scale (WSRS) was employed by the same physician to assess facial wrinkles pre-treatment and one-week post-treatment. Additionally, patients completed a satisfaction questionnaire one week after the final treatment. The WSRS consists of five grades: Grade 1 (no obvious wrinkles); grade 2 (mild, fine, and light wrinkles); grade 3 (moderate, deep wrinkles that disappear when stretched); grade 4 (severe, visible long and deep wrinkles with a length of less than 2 mm when stretched); and grade 5 (very severe, extremely deep and long wrinkles, with V-shaped wrinkles of 2 to 4 mm still visible after stretching). The global aesthetic improvement scale (GAIS) was used for the satisfaction assessment, with patients rating their experience one week after the last treatment: 1 (very significant improvement), 2 (significantly improved), 3 (improved), 4 (unchanged), and 5 (worse than before). Total satisfaction was calculated as the number of cases scoring 1, 2, or 3 divided by the total number of cases, multiplied by 100%. Adverse reactions were documented during and immediately after treatment, including pain level, burns, flushing, petechiae, and ecchymosis[13].

Statistical analysis

Data analysis was performed using SPSS 20.0 statistical software. The χ²-test was utilized for comparative analysis of categorical data, while measurement data were expressed as mean ± SD. The t-test was applied for comparisons between two groups, and analysis of variance was employed for comparisons among multiple groups. All statistical analyses were conducted using bilateral tests, with significance defined as P < 0.05.

RESULTS

WSRS scoring results

One week after completing three treatments, the WSRS scores were significantly lower compared to pre-treatment levels, indicating a reduction in wrinkles (including forehead lines, periorbital wrinkles, and nasolabial folds) with statistically significant differences (P < 0.05, Table 1, Figure 1).

Figure 1 Female patient before and after treatment. A: Significant improvement in facial sagging and fat accumulation, with a clearer overall facial contour; B: Substantial improvement in the drooping appearance of the mid and lower face, with a more defined facial contour and significant improvement in periorbital fine lines, upper eyelid laxity, and enhanced definition of the double eyelid line.

Table 1 Comparison of wrinkle severity scores of patients before treatment and one week after three treatments.

Duration of treatment	Cases	Score	t	P value
Before treatment	60	3.00 ± 0.79	2.58	0.02
One week after three treatments	60	2.71 ± 0.47

GAIS scoring results

Based on GAIS scores evaluated one week after three treatments, outcomes indicated improvement in most patients compared to their pre-treatment status: 7 patients were rated as 4 (no change), 25 patients as 3 (improved), 18 patients as 2 (significantly improved), and 10 patients as 1 (remarkable improvement). A total of 53 patients expressed satisfaction with their results (Table 2).

Table 2 Comparison of global aesthetic improvement scale scoring results one week after three treatments.

Duration of treatment	Cases	The improvement is remarkable	A marked improvement	Have an improvement	No change	Worse than before
One week after three treatments	60	10	18	25	7	0

Occurrence of adverse reactions

During treatment, patients mainly reported tolerable pain and a sensation of heat. Mild diffuse flushing commonly appeared in the treated facial area immediately post-treatment, which subsided naturally within four hours. Additionally, five patients exhibited purple petechiae or small ecchymoses (miliary-sized) in the mid and lower face, which resolved naturally within 3-5 days. No patients experienced burns or severe pain, nor was treatment interrupted for any patient.

DISCUSSION

As we age and are continuously exposed to external environmental factors, the synthesis of dermal collagen decreases, while the transcription of matrix metalloproteinases increases, leading to the denaturation and deposition of elastic fibers. These changes culminate in the appearance of wrinkles, pigmentation, and skin sagging[14]. Facial aging primarily affects appearance, which can impact mood and quality of life. With improvements in living standards, the public’s interest in and demand for external beauty have risen sharply. According to a 2017 report by the American Society for Aesthetic Plastic Surgery, over 3.239 million people in the United States opted for non-surgical medical cosmetic procedures in 2017, marking a 4.2% increase from 2016[15]. This trend highlights the growing acceptance of non-invasive and effective facial rejuvenation among patients.

Among various anti-aging therapies, laser and radiofrequency treatments are among the least invasive. However, lasers may not significantly improve facial wrinkles or sagging due to their shallow penetration depth. Consequently, patients often prefer radiofrequency therapy for non-invasive wrinkle and sagging treatment. Current radiofrequency options include monopole, bipolar, microneedle, and dot-array systems. While microneedle and dot-array techniques are minimally invasive and typically require local anesthesia, monopole radiofrequency is more effective, albeit associated with greater discomfort.

Radiofrequency technology operates on the principle of generating thermal effects by acting on water molecules in tissues. In this process, polar water molecules rotate rapidly in an alternating electric field, generating heat through friction without requiring the ablation of the epidermis and dermis. This precise control over penetration depth makes it suitable for various skin types, offering wide applicability and enhanced comfort. Radiofrequency therapy can smooth wrinkles, shrink pores, melt fat, promote skin firmness and lift, and reshape facial and body contours[16]. Radiofrequency, an electromagnetic wave with a frequency range of 3 kHz to 300 GHz, emits energy in the form of radiation or current. While radiofrequency ablation and cryoablation are utilized for minimally invasive treatments in conditions such as sleep apnea, heart disease, and liver tumors[17], non-ablation radiofrequency energy is primarily employed for skin tightening and enhancement in cosmetic surgery[18]. The thermal effect generated by the current flowing through tissues promotes collagen shrinkage and denaturation, facilitating the synthesis of new collagen and elastin[19]. Research indicates that radiofrequency currents may upregulate sirtuins 6 (SIRT6) expression and downregulate SIRT1, SIRT3, SIRT4, SIRT6, and SIRT7, creating a favorable environment for collagen deposition and extending fibroblast lifespan[20]. Northem imprinting analysis has demonstrated significantly higher mRNA expression levels of type I collagen in radiofrequency-treated skin compared to untreated skin[21]. Furthermore, radiofrequency energy can penetrate deep into the dermis and adipose tissue, enhancing lipase secretion and adipocyte metabolism, which aids in reducing localized fat deposits[22].

In our study, we utilized the Accent XL system (Alma Lasers, Ltd., Thermolift 2.0), which features converged radiofrequency technology with two handpieces designed for facial and periorbital treatment. Under a 40.68 MHz electromagnetic field, intermolecular resonance heating raises the temperature of the target area to 55-65 °C[23]. This immediate thermal effect denatures collagen by disrupting the hydrogen bonds in its triple helix structure[24]. Additionally, it enhances local blood flow, stimulates fat metabolism, and promotes lipase-mediated degradation of triglycerides, leading to localized fat reduction[25]. The skin probe incorporates a cooling system that maintains a temperature of 35-45 °C to prevent burns. Utilizing phase shifting and waveform compression techniques allows for more precise and concentrated energy delivery. The treatment parameters included depths of 1.5 mm, 3 mm, and 4.5 mm for various settings[26]. Patients reported immediate tightening sensations, enhanced facial contours, and improved skin elasticity without experiencing erythema, edema, burns, or pigmentation as adverse reactions; the optimal effects were observed at three months post-treatment. Dermatologists confirmed significant improvements in facial aging conditions through comparative photography, and objective analysis with the Visia skin analyzer indicated statistically significant reductions in wrinkle scores (P < 0.05).

During the treatment, it is crucial to consider individual differences in heat tolerance across various facial areas, select appropriate parameters, and continuously monitor skin temperature to avoid adverse reactions like burns. By combining ring bipolar and wave-phase monopole radiofrequency techniques, different depths of subcutaneous tissue can be effectively heated and tightened in a single session, promoting collagen proliferation. Periocular treatments utilized a monopole handpiece, alternating between 15 seconds of heating and 5 seconds of cooling. Anesthesia is typically unnecessary, and at least one treatment course is required to maintain results. Any post-treatment burning sensations or erythema typically resolve within 24 hours. The long-term effects of facial lifting and objective assessment criteria warrant further investigation.

CONCLUSION

Radiofrequency technology offers a promising solution for treating facial aging due to muscle relaxation and subcutaneous fat atrophy. Its strong penetration capability makes it suitable for all skin tones. However, the treatment course can be lengthy, and while it is effective for static and fine lines, its impact on dynamic and moderate to severe wrinkles may be limited[27,28]. Clinical observations indicate that thermoplastic radiofrequency therapy for facial rejuvenation is effective, safe, painless, and requires no recovery time, making it a valuable option for clinical application. For patients with severe facial aging stemming from multiple causes, combining two or more treatment methods may also be beneficial.