Microneedle Fractional Radiofrequency (MFRF) is a minimally invasive skin rejuvenation and treatment technique that uses arrays of insulated or non-insulated microneedles to deliver radiofrequency energy directly to target tissues in one or more predetermined layers. By combining the thermal effects of radiofrequency with the mechanical micro-injuries from the microneedles, it achieves both cosmetic and therapeutic goals.
In recent years, microneedle fractional radiofrequency technology has been widely adopted in the field of dermatological aesthetics. To standardize its procedures and ensure the safety and efficacy of clinical applications, several professional groups—including the Laser Aesthetics Group and the Skin Aesthetics Group of the Chinese Medical Association’s Medical Aesthetics and Cosmetology Branch, and the Laser Aesthetics Group of the Chinese Association of Plastic and Aesthetic Physicians—have jointly developed the 2025 Expert Consensus on Clinical Applications of Microneedle Fractional Radiofrequency.
1. Basic Principles and Mechanisms of MFRF
Microneedle Fractional Radiofrequency (MFRF) uses microneedles to deliver continuous-type or pulsed-type radiofrequency energy to the epidermis, dermis, and even subcutaneous tissue. This creates localized microthermal zones (MTZs) that immediately tighten collagen fibers. The thermal effects, combined with the mechanical micro-injury from the needles, activate the skin’s wound healing response, inducing the release of multiple growth factors and stimulating the migration and proliferation of keratinocytes and fibroblasts. This promotes the regeneration of collagen and elastin fibers, forming the fundamental principle behind MFRF’s cosmetic and therapeutic skin applications.
Continuous and pulsed radiofrequency energy modes act through different thermal mechanisms in the skin, achieving varied treatment goals. Additionally, MFRF can temporarily disrupt the skin’s stratum corneum barrier, enhancing transdermal absorption of active ingredients and serving as a method for transdermal drug delivery. MFRF offers advantages such as precise depth control, minimal damage to the epidermis and basement membrane, no chromophore-specific absorption, low pain levels, rapid recovery, and minimal downtime.
1.1 Insulated and Non-Insulated Microneedles
MFRF delivers radiofrequency energy through microneedles into targeted tissue layers. Depending on whether the needle body is insulated, the microneedles can be classified as insulated or non-insulated.
1.1.1 Insulated Microneedles
- Mechanism: Only the needle tip emits energy, while the needle shaft remains insulated. This concentrates the thermal effect around the needle tip’s target tissue, ensuring precise energy delivery.
- Treatment Modes:
- Single-layer: Energy is delivered at a predetermined single treatment depth.
- Multi-layer: Energy is delivered at multiple preset treatment depths as the needle is withdrawn, allowing a single insertion to cover different tissue layers. Clinically, this can reduce treatment frequency and improve efficiency.
1.1.2 Non-Insulated Microneedles
- Mechanism: The entire needle body conducts radiofrequency energy, creating a broader heating effect within the skin.
- Relative Advantages: Generates a certain thermal effect on the epidermis.
- Clinical Applications: Used to treat common acne, acne scars, rosacea, and sensitive skin. However, there is an increased risk of scabbing and hyperpigmentation compared to insulated microneedles.
Research has shown that during bipolar radiofrequency treatment with non-insulated microneedles, tissue coagulation begins at the needle tip and gradually forms a tear-shaped thermal coagulation zone as the conduction time increases. This suggests that optimizing the treatment parameters of non-insulated microneedle bipolar radiofrequency can precisely control the thermal effect, thereby reducing the risk of adverse reactions such as scabbing and hyperpigmentation.
1.2 Suction-assisted and Non-Suction Microneedles
MFRF Classification
- Negative Pressure Microneedle Fractional Radiofrequency
- Uses intelligent negative pressure technology to automatically suction and adhere to the skin for treatment
- Suitable for loose skin areas such as around the eyes and neck
- Non-Negative Pressure Microneedle Fractional Radiofrequency
- Foot pedal controlled, stamp-like treatment
- Commonly used in areas with good facial tissue support, facilitating stamp-like application
2. Clinical Applications of MFRF
MFRF is suitable for all skin types and is particularly widely used in Asian populations. Its clinical applications mainly include facial, periorbital, neck rejuvenation, and treatments for enlarged pores, striae distensae (commonly known as stretch marks), as well as improvements in skin conditions such as acne vulgaris, acne scars, bromhidrosis (axillary odor), rosacea, melasma, and sensitive skin.
2.1 Indications
2.1.1 Skin Rejuvenation
2.1.1.1 Facial Rejuvenation
- Clinical Manifestations: Facial wrinkles, skin laxity, undefined jawline, dull and rough skin texture.
- Clinical Studies: In a study of 24 patients with facial photoaging who underwent three MFRF treatments, the global scores for photoaging (GSP) significantly decreased. There was a statistically significant reduction in the number of wrinkles and an improvement in skin texture and firmness. Another study confirmed that after treatment, patients with facial laxity showed noticeable skin tightening and wrinkle reduction, with effects lasting at least six months, demonstrating the efficacy of MFRF in facial rejuvenation.
2.1.1.2 Periorbital Rejuvenation
- Clinical Manifestations: Thinning of the epidermis and reduction/degeneration of elastic and collagen fibers in the dermis.
- Clinical Studies: After negative pressure microneedling treatment, patients showed a reduction in periorbital wrinkles and improved skin radiance. Histological studies showed significant dermal thickening, with collagen fibers arranged more orderly and densely. Expression of type I collagen and elastic fibers increased, indicating that MFRF is a safe and effective method to reduce static periorbital wrinkles.
2.1.1.3 Neck Rejuvenation
- Clinical Presentation: Skin laxity, fat accumulation, and deepening neck lines.
- Clinical Research: MFRF promotes collagen contraction and regeneration in neck skin, improves microcirculation, and triggers self-repair, thereby firming the neck skin and reducing wrinkles. In a study of 24 patients with neck laxity treated with negative pressure microneedles, after four months, there was a reduction in neck wrinkles, improved contours, and an 83% satisfaction rate. Additionally, there was an observed increase in elastic and collagen fiber density, significantly improving neck aging.
2.1.1.4 Enlarged Pores
- Clinical Definition: Pores with an area greater than 0.3–0.5 mm².
- Common Areas: Face and scalp.
- Causes: Excess sebum production, inflammation from Propionibacterium acnes, and photodamage-related “aging-type” pores.
- Clinical Research: In a study involving 75 patients, MFRF treatments significantly improved enlarged pores on the nose, cheeks, and forehead, with the nose showing the greatest improvement. Multiple sessions of MFRF provided better results than a single session, with effectiveness increasing with the number of treatments.
2.1.1.5 Stretch Marks (Striae)
- Causes: Rapid weight gain leads to elastic fiber breakdown and collagen fiber rupture, forming “atrophic scars.”
- Common Areas: Thighs, lower abdomen, and breasts.
- Clinical Research: In a study of 10 patients with abdominal stretch marks treated with MFRF, after two months, there was an 80% improvement rate, enhanced skin elasticity, and reduced pigmentation. Another study compared MFRF with fractional laser treatments on both sides of the abdomen in 14 patients and found MFRF was more effective in improving appearance and stimulating collagen and elastic fiber production.
2.1.2 Acne Vulgaris
- Causes: Hormone-induced excessive sebum production, abnormal follicular keratinization, proliferation of Propionibacterium acnes, and inflammation.
- Clinical Presentation: Comedones, papules, pustules, nodules, and cysts.
- Clinical Treatment: Combining oral minocycline hydrochloride with MFRF achieved an 86.6% efficacy rate in moderate to severe facial acne, with a relapse rate as low as 19.2%.
2.1.3 Acne Scars
- Causes: Inflammation, infection, improper management.
- Clinical Types: Atrophic, hypertrophic, and keloid scars. Atrophic scars can be further categorized into rolling, boxcar, and icepick types.
- Clinical Research:
- Ding et al. treated 126 cases of atrophic acne scars with MFRF, finding improvement in all patients. More sessions correlated with better outcomes, especially for those receiving more than three treatments.
- Huang et al. treated 40 cases of various acne scars with MFRF, noting that rolling scars improved fastest, while boxcar scars showed the most significant improvement after three months, with outcomes improving with more sessions.
2.1.4 Axillary Odor (Bromhidrosis)
- Causes: Sex hormones, nervous system mechanisms, and diet.
- Clinical Presentation: Underarm odor with excessive sweating.
- Clinical Research: In 48 patients treated with MFRF, the improvement rate was 93.75%. Compared to surgery, patients had higher one-month satisfaction rates, lower Dermatology Life Quality Index (DLQI) scores, lower relapse rates, no serious adverse events, and no need for post-procedure immobilization.
2.1.5 Rosacea
- Clinical Presentation: Flushing, transient redness, persistent erythema, papules, pustules, and telangiectasia.
- Clinical Treatment: Monotherapy often fails to stabilize disease or prevent relapse, and long-term use may cause side effects. MFRF is an emerging energy-based treatment option.
- Clinical Research: In a study of 21 rosacea patients receiving two MFRF treatments (one month apart) on one side of the face, immunohistochemical staining showed reduced inflammation, innate immune markers, and angiogenesis markers, with significant clinical symptom improvement.
2.1.6 Melasma
- Clinical Presentation: Symmetrical light to dark brown patches on the face.
- Mechanism of Action: MFRF stimulates extracellular matrix remodeling, rejuvenates aging fibroblasts, and accelerates epidermal turnover. It also promotes dermal collagen regeneration, disrupts abnormal melanocytes, and repairs the damaged basement membrane to prevent persistent pigmentation.
- Clinical Research: In 124 patients, MFRF significantly reduced the modified Melasma Area and Severity Index (mMASI), with 65.32% showing moderate to significant improvement, high patient satisfaction, and no serious side effects. Another study found that MFRF helped maintain improvements in patients after two months of drug therapy, reducing relapse risk.
2.1.7 Sensitive Skin
- Mechanism of Action: MFRF stimulates dermal collagen rearrangement, increases dermal thickness and tolerance, and downregulates transient receptor potential vanilloid (TRPV) channels involved in neural sensation and inflammation, improving symptoms like redness and burning.
- Clinical Research: MFRF significantly improved rosacea patients’ redness, flushing, papules, and facial burning without damaging the epidermal barrier.
2.1.8 Other Uses
MFRF can also be used for hyperhidrosis, seborrheic keratosis, hand rejuvenation, facial overfilling syndrome, post-mesotherapy nodules, hair loss (androgenetic alopecia, alopecia areata), dorsocervical fat pad (“buffalo hump”), neurodermatitis, senile purpura, chronic eczema, and port-wine stains.
2.2 Clinical Parameter Selection
- Comprehensive assessment of skin thickness, treatment indications, patient tolerance, and device specifications is needed before choosing parameters.
- Lower energy and shallower penetration are recommended for thinner skin areas (forehead, around the eyes).
- For cheeks, neck, and abdomen, higher power, pulse width, and penetration depth can be used.
2.3 Combining MFRF with Other Aesthetic Treatments
2.3.1 Topicals and Injectables
Combining with mesotherapy products, salicylic acid, regenerative injectables, or minoxidil immediately post-procedure can enhance effects for wrinkles, elasticity, scars, and hair loss.
2.3.2 Precautions
- When combined with injectables, carefully consider thermal effects, inflammation, and impact on product safety and efficacy.
- When using botulinum toxin, perform MFRF first, waiting at least three days before injections.
2.3.3 Energy-Based Combination
- When combined with CO₂ lasers for acne scars, MFRF compensates for laser depth limitations, improving efficacy and satisfaction.
- When combined with Q-switched lasers for melasma, it significantly reduces pigmentation and relapse risk.
2.4 Contraindications
- Pacemakers or implantable defibrillators
- Pregnancy
- Uncontrolled local skin infections
- Bleeding disorders or systemic diseases
- Malignant or suspicious skin tumors in the treatment area
- Ongoing chemotherapy or radiotherapy
- Neurological or psychiatric disorders that hinder cooperation
- Metal foreign bodies, unknown injectables or fillers in the treatment area
- Other physician-assessed contraindications
3 Treatment Methods
3.1 Pre-Treatment
- Consultation and history-taking
- Explain procedure and risks, sign informed consent
- Take pre-treatment photos (front, 45°, 90° angles after cleansing)
3.2 Preparation
- Wear disposable mask and cap
- Disinfect equipment and handpieces
- Apply topical anesthesia to treatment area
- Remove anesthetic and disinfect the area
3.3 Procedure
- Principles:
- Sterile technique
- “Stamping” mode: 20% overlap for non-negative pressure, 50% for negative pressure. Repeat or intensify in tolerable areas.
- Dedicated, single-use electrodes.
- Electrode Setup:
- Wear sterile gloves, install electrodes in a clean environment without touching the needle area. Negative pressure electrodes should have the filter pipe fully inserted and secured.
- Electrode Operation:
- Non-Negative Pressure: Keep handpiece perpendicular and tight to the skin, pedal-controlled for continuous treatment.
- Negative Pressure: Lightly touch treatment area, allow suction, lift to smooth skin, auto-needle deployment, quickly remove to avoid repeated suction.
3.4 Post-Treatment Care
- Immediate:
- Soothe with hydrogel dressings
- Use repair masks, low-level laser therapy (LLLT), or topical growth factors
- Apply antibiotic ointments to prevent infection; corticosteroid ointments if needed
- At Home:
- Wash face with water after 24 hours
- Normal skincare can resume after 2–3 days
- Moisturize and apply physical sun protection
4 Adverse Reactions & Prevention
4.1 Swelling and Redness
- Clinical Manifestation
- Symptoms: Mild swelling and diffuse redness with slight exudation are visible immediately after treatment.
- Influencing Factors:
- Treatment energy density
- Individual patient differences
- Immediate post-treatment care
- Resolution Time: Gradually resolves on its own within 2–7 days.
- Treatment Strategies:
- Immediate: Application of medical-grade hydrogel dressings
- Combined: Low-level light therapy (LLLT) and repair products such as recombinant collagen
4.2. Petechiae or Bruising
- Clinical Manifestation: Localized petechiae occasionally appear on the skin.
- Common Sites: Around the eyes and other thin, vascular-rich skin areas.
- Cause: Improper operation of the negative-pressure microneedle electrode.
- Resolution Time: Typically fades on its own within 5–7 days.
4.3. Reactive Acneiform Lesions
- Clinical Manifestation: Small local pustules, with occasional isolated nodules.
- Treatment Strategies: Managed according to standard acne treatment protocols. Exclude allergic reactions and secondary infections.
4.4. Hyperpigmentation
- Causes:
- Inflammatory response
- UV exposure
- Impaired skin barrier function
- Improper post-care
- Poor adherence of non-insulated microneedles
- Resolution Time: Generally fades within approximately 3–7 days.
- Treatment Strategies: Strict physical sun protection, introduction of tranexamic acid, or combined use of laser therapy to accelerate fading.
4.5. Scarring
- Cause: Excessive energy release in the epidermal layer.
- Preventive Measures: Avoid improper operation and parameter settings.
- Treatment Measures: Anti-scar treatments.
5. Basic Requirements for Medical Institutions and Operators
5.1 Requirements for Medical Institutions
5.1.1 MFRF treatment can only be performed in hospitals or medical aesthetic institutions with medical qualifications, and relevant management systems must be established and improved.
5.1.2 There must be consultation rooms and photography rooms, with a system in place for preoperative discussions and signed informed consent forms. A complete patient medical record should be established.
5.1.3 A dedicated treatment room must be set up, storing MFRF treatment devices, consumables, medications, etc. Proper disinfection and isolation should be carried out, with essential emergency equipment and drugs available.
5.2 Qualifications of Supervising Physicians and Operators
5.2.1 Medical staff performing MFRF procedures must hold medical licenses in dermatology, plastic surgery, or medical aesthetics, or possess a main aesthetic physician license. They must undergo relevant training and pass competency assessments. Supervising physicians must hold a medical license and have relevant procedural experience.
5.2.2 Personnel involved in MFRF treatments should undergo professional skills training, mastering knowledge of indications, contraindications, basic equipment and drug principles, fundamental operational procedures, perioperative care, expected outcomes, potential adverse effects, and basic prevention and management strategies.
✰ The content of this article is for academic discussion only and is intended for medical professionals.
