The Efficacy and Safety of Radiofrequency Microneedling for Melasma: A Systematic Review and Qualitative Evidence Synthesis

Abstract

Melasma is a chronic, relapsing hyperpigmentation disorder that is difficult to treat, particularly in Fitzpatrick skin types III-V, where energy-based devices frequently induce postinflammatory hyperpigmentation (PIH). Radiofrequency microneedling (RFMN) has emerged as a promising alternative because it targets dermal pathology while minimizing epidermal injury. Systematically evaluate the efficacy, safety, and mechanistic rationale of RFMN for melasma. A PRISMA 2020 compliant search of PubMed, Embase, Cochrane CENTRAL, and LILACS (2014-2025) identified clinical studies evaluating RFMN alone or in combination therapies. Risk of bias was assessed using Joanna Briggs Institute tools. Owing to clinical and methodological heterogeneity, a qualitative synthesis was performed. Across 12 included studies, RFMN consistently improved Melasma Area and Severity Index (MASI) or modified MASI scores and melanin indices, with effects maintained up to 6 months. Histological evidence demonstrated reductions in dermal senescence markers and partial restoration of basement-membrane integrity. RFMN also showed a favorable safety profile, with a low incidence of PIH in darker phototypes. Combination treatment, particularly with low-fluence Q-switched Nd:YAG laser produced greater pigment reduction than monotherapy. RFMN is an effective and safe modality for melasma, offering advantages over pigment-directed lasers by addressing dermal mechanisms and limiting PIH risk. It may serve as a first-line energy-based therapy.

Level of Evidence:3 (Therapeutic)

Melasma is a chronic facial hyperpigmentation, common in women with intermediate-to-dark phototypes and associated with significant quality-of-life impairment.¹ Standard care combines broad-spectrum photoprotection with topical lightening agents and oral or topical tranexamic acid. Yet, many patients show incomplete clearance or early relapse, particularly in Fitzpatrick skin types III-VI, where energy-based devices carry a high risk of postinflammatory hyperpigmentation (PIH).² Recent literature reframes melasma as a photoaging-related disorder in which epidermal melanocyte hyperactivity coexists with dermal changes such as basement-membrane disruption, solar elastosis, and a senescent fibroblast milieu that sustains melanogenesis.³

Radiofrequency microneedling (RFMN) delivers fractionated radiofrequency (RF) energy through semi-insulated needles into the dermis while largely sparing the epidermis, promoting dermal remodeling with a theoretically lower risk of postinflammatory dyspigmentation.⁴ Clinical studies have evaluated RFMN as monotherapy and as an adjunct to other therapies in predominantly darker phototypes, reporting reductions in melasma severity with acceptable tolerability.^5-7 However, existing reviews of melasma and microneedling usually pool different microneedling techniques or briefly mention RFMN and lack a PRISMA compliant synthesis focused on RFMN.^8,9

This systematic review, therefore, provides the first focused, PRISMA-based synthesis of the efficacy and safety of RFMN for melasma, particularly in Fitzpatrick skin types III-VI, and integrates these data with current pathophysiological concepts to clarify its role in contemporary melasma management.

METHODS

The protocol for this systematic review was prospectively registered in PROSPERO (CRD420251104345). The review followed PRISMA 2020 guidelines for reporting systematic reviews.

Information Sources and Strategy

We conducted a systematic review of PubMed, Embase, Cochrane CENTRAL, and LILACS for studies published between January 1, 2014, and June 30, 2025. The search strategy combined MeSH/Emtree terms and free-text keywords related to RFMN and melasma (see Appendix A for the complete search strategy). The final search was completed on July 16, 2025.

Study Selection and Screening

Three reviewers independently screened the titles and abstracts of all identified records using the Rayyan web platform. Disagreements at this stage were resolved by consensus or, when necessary, by arbitration with a fourth reviewer.

We retrieved and evaluated the full texts of all potentially eligible studies. Three reviewers independently assessed eligibility against the predefined inclusion and exclusion criteria, focusing on RFMN intervention details, study methodology, reporting of melasma-related outcomes, and the availability of extractable data. Disagreements were resolved through discussion, with a fourth reviewer serving as an arbitrator when needed. Reasons for exclusion were systematically documented.

A complete list of all full-text screened studies, including bibliographic details and specific reasons for exclusion, is provided in Appendix B.

Data Extraction

The lead reviewer performed the initial data extraction into a standardized template. To ensure accuracy, second and third reviewers then cross-checked the extracted data from all studies. The 3 reviewers discussed any instances of disagreement until they reached a consensus. The structured data extraction matrix is available in Appendix B.

Quality Appraisal (Risk of Bias)

The methodological quality and risk of bias of the included studies were assessed by 2 independent reviewers using the Joanna Briggs Institute Critical Appraisal Checklists. The specific checklists for randomized controlled trials, cohort studies, and quasi-experimental studies were applied as appropriate to each study's design. Disagreements between the reviewers were resolved through discussion or by consulting the lead reviewer. The complete results of this assessment for each study are provided in Appendix C.

Data Synthesis

We synthesized the findings using a thematic analysis approach. Findings were analyzed across 5 prespecified domains: (1) efficacy in reducing pigmentation and disease severity, (2) safety and tolerability profile, (3) proposed mechanisms of action, (4) RFMN as a synergistic and adjuvant therapy, and (5) patient-reported outcomes and satisfaction (Table 1). Because of significant heterogeneity, a narrative synthesis was conducted. The confidence in findings was evaluated using the GRADE-CERQual approach. A detailed summary of the CERQual assessments for each key finding is available in Appendix D.

Table 1.

Thematic Synthesis

Theme	Key finding	Magnitude of effect (range)	Supporting studies	Total patients (n)
Efficacy in reducing pigmentation	Significant reduction in MASI/mMASI scores	21.2% to 31% improvement	4/12	n = 127 (4, 6, 12, 17)
	Superior efficacy of RFMN + QSNY laser vs laser alone	Significantly greater mMASI and melanin index reduction	3/12	n = 154 (5, 14, 16)
	Effective maintenance therapy to prevent relapse	Sustained improvement vs relapses to near-baseline on the untreated side	1/12	n = 15 (4)
Safety and tolerability	Incidence of transient erythema/edema	Very common, resolving within hours to 7 days	7/12	n = 254 (5, 6, 10, 11, 12, 14, 17)
	Mean pain score (0-10 VAS)	2.0 to 3.8 (mild to moderate)	4/12	n = 62 (5, 6, 11, 13)
	Incidence of PIH	0% in several studies; rebound hyperpigmentation in 18% (combination) vs 29% (laser only)	6/12	n = 364 (4, 5, 11, 12, 14, 17)
Proposed mechanisms of action	Reduction of dermal senescence (p16INK4A + fibroblasts)	Significant reduction posttreatment	4/12	n = 103 (13, 15, 16, 17)
	Remodeling of dermal structure (↑ collagen, ↑ basement-membrane integrity)	Increased procollagen 1 and type IV collagen	4/12	n = 103 (13, 15, 16, 17)
Synergistic and adjuvant therapy	Patient preference for RFMN + laser over laser alone	Higher patient satisfaction scores	2/12	n = 129 (5, 14)
	Efficacy of RFMN for topical drug-delivery (eg, tranexamic acid and cysteamine)	Significant mMASI improvement with the combination	2/12	n = 44 (7, 13)
Patient-reported outcomes and satisfaction	Patient satisfaction rate	>70% satisfied in the reported studies	3/12	n = 167 (5, 12, 14)
	Tolerability and minimal downtime	Rapid return to daily activities; minimal interference	5/12	n = 117 (5, 6, 12, 13, 15)

Table organizing the key findings of the qualitative synthesis into 5 prespecified domains: (1) efficacy in reducing pigmentation and disease severity, (2) safety and tolerability profile, (3) proposed mechanisms of action, (4) RFMN as a synergistic and adjuvant therapy, and (5) patient-reported outcomes and satisfaction. Each domain includes a summary of the synthesized evidence from the included studies. Data are presented as the range of results reported across the included studies. The denominator for contributing studies is the total number of included studies (n = 12). MASI, Melasma Area and Severity Index; mMASI, modified MASI; PIH, postinflammatory hyperpigmentation; QSNY, Q-switched Nd:YAG; RFMN, radiofrequency microneedling; VAS, visual analog scale.

Assessment of Heterogeneity

We assessed heterogeneity among the included studies by examining variability in several key areas. Substantial clinical heterogeneity was observed, driven by differences in the RFMN devices used (eg, Sylfirm, Secret, and Intensif), treatment parameters (needle depth, energy settings, and number of sessions), and treatment paradigms (monotherapy vs combination with other therapies). Methodological heterogeneity was also present, stemming from the inclusion of different study designs (randomized controlled trials [RCTs], cohort, and quasi-experimental) and variations in outcome measurement. This high degree of heterogeneity precluded a quantitative meta-analysis and was therefore explored narratively through the thematic synthesis.

RESULTS

Study Selection

A total of 148 articles were identified through database searching and additional sources. After removing duplicates and applying inclusion criteria, 12 articles were included in the final synthesis (see PRISMA diagram, Figure 1).

Figure 1.

PRISMA flow diagram. Flow diagram illustrating the study selection process for the systematic review, from initial identification of records through database searching to the final inclusion of studies. The diagram details the number of records identified, duplicates removed, titles/abstracts screened, full-text articles assessed for eligibility, and studies included in the qualitative synthesis. The final database search was completed on July 16, 2025.

Characteristics of Included Studies

This systematic review synthesizes evidence from 12 studies investigating the efficacy and safety of RFMN for the treatment of melasma.^4-7,10-17 The included studies, published between 2018 and 2025, encompass a range of methodological approaches. The evidence base comprises 4 RCTs, with the remainder consisting of prospective cohort studies and clinical trials.^4,6,7 Geographically, the research is predominantly centered in East Asia, with 7 studies conducted in South Korea, 2 in China, and 1 each in Taiwan, Thailand, and Israel, reflecting the condition's higher prevalence in populations with Fitzpatrick skin types III and IV.^{4-7,10,11,12-17}

The included studies comprised 394 participants. In the pilot randomized trial by Gulfan et al, 30 women with melasma were enrolled, and 26 completed the 6-month follow-up.⁶ It was included in the per-protocol efficacy analyses, ensuring that the denominator for outcome reporting corresponds specifically to patients with melasma. The cohorts were overwhelmingly female (ranging from 93.3% to 100%), with participant ages spanning from the early 30s to the 60s; however, the mean age in most studies fell within the fourth and fifth decades of life. Fitzpatrick skin types III and IV were most represented, consistent with the epidemiology of melasma. A significant proportion of the studied population had melasma characterized as mixed-type or refractory to previous conventional therapies, such as topical depigmenting agents and laser toning.^6,7,17

The type of microneedle used (insulated, semi-insulated, vs noninsulated) was a distinguishing technical feature among the RFMN studies. As detailed in Table 2, of the 10 studies that utilized an RFMN system, needle type was explicitly reported in 8. Among these, 7 studies employed devices with noninsulated needles, whereas 1 study used a system with insulated needles.^{4,5,9,10,11,14,16,17} The needle type was not specified in 2 RFMN studies.^14,17 The remaining 2 studies utilized noninvasive, contact-based RF devices for which needle classification is not applicable.^10,12

Table 2.

Characteristics of Included Studies (n = 12)

First author (year)	Country	Study design	Participants (n, F/M)	RFMN device	RF needle type/mechanism	Treatment parameters (energy, depth)	Protocol (sessions, interval)	Key outcomes measured
Akerman (2025)13	Israel	Cohort study	14 (14/0)	Intensif (EndyMed)	Noninsulated microneedling	Power: 14 W; depth: 1.5 mm	4 sessions, 3-week intervals	mMASI, erythema, patient satisfaction, and safety
Chen (2025)9	China	Prospective clinical trial	20 (16/4)	INTRAcel (Jeisys)	Insulated microneedling	Power: 12.5 W; depth: 1.5-2.0 mm (area dependent)	2 sessions, 3-month interval	MASI, melanin index, barrier function, and safety
Gulfan (2022)6	Thailand	Randomized controlled trial	30 (30/0)	SYLFIRM (VIOL)	Noninsulated microneedling	Level 2; depth: 1.5 and 0.8 mm (multipass)	3 sessions, 2-week intervals	mMASI, melanin index, erythema index, and skin roughness
Han (2024)4	South Korea	Randomized controlled trial	15 (15/0)	Sylfirm X (VIOL)	Noninsulated microneedling	Pulsed wave (PW2); depth: 0.3 and 0.8 mm (multipass)	Phase 1: bi-weekly (2 months) Phase 2: monthly (6 months)	mMASI, chromameter L* value, relapse rate, and safety
Jung (2019)5	South Korea	Prospective study	15 (14/1)	Secret (Ilooda)	Noninsulated microneedling	Intensity: 50%; depth: 1.0 mm	5 sessions, 2-week intervals	Melanin index, PSI, patient satisfaction, and safety
Kim (2019)11	South Korea	Prospective Study	3 (3/0)	SYLFIRM (VIOL)	Noninsulated microneedling	Level 2; depth: 1.5 mm	5 sessions, 2-week intervals	Chromameter L*, p16INK4a (senescence), procollagen 1
Kwon, H.H. (2019)14	South Korea	Cohort study	114 (109/5)	Secret (Ilooda)	Not specified	Intensity: 20-30; depth: 0.5-1.0 mm	10 sessions, 1-week intervals	mMASI, physician's assessment, and rebound hyperpigmentation
Kwon, S.-H. (2021)10	South Korea	Prospective study	10 (10/0)	Forma (InMode)	Contact RF	Energy: 62 mJ; target temp.: 43°C	3 sessions, 3-week intervals	Melanin index, IGA, and histology (senescence and collagen)
Lee (2021)16	South Korea	Prospective study	25 (25/0)	Sylfirm X (VIOL)	Noninsulated microneedling	Pulsed wave; depth: 0.3 mm	5 sessions, 2-week intervals	Hemi-MASI, melanin index, wrinkle scale, and GAIS
Park (2022)17	South Korea	Prospective study	44 (42/2)	Not specified	Not specified	Energy: 1.39-1.59 J/cm2; depth: 1.0-1.5 mm	5 sessions, 2-week intervals	Melanin index, IGA, PGA, and TEWL
Tsai (2025)7	Taiwan	Randomized controlled trial	30 (30/0)	Sylfirm (VIOL)	Noninsulated microneedling	Level 2; depth: 1.5 mm	4 sessions, monthly intervals	mMASI, VISIA analysis, and safety
Zhang (2025)12	China	Cohort study	38 (38/0)	ARF001 (AMIRO)	Contact RF noninvasive	Home-based device (integrated red light)	Thrice weekly for 4 weeks, then 4-week discontinuation	mMASI, melanin index, VISIA, and dermal thickness

Summary table of the 12 studies included in the systematic review. The table presents key study details, including author(s) and year, country, study design, participant characteristics (number, skin type, and melasma type), intervention and comparator details (RFMN device, parameters, and combination therapies), primary outcomes, and follow-up duration. GAIS, Global Aesthetic Improvement Scale; IGA, Investigator Global Assessment; MASI, Melasma Area and Severity Index; mMASI, modified MASI; PGA, Physician Global Assessment; PIH, postinflammatory hyperpigmentation; RFMN, radiofrequency microneedling; TEWL, Transepidermal Water Loss.

A notable characteristic of the interventions was the significant heterogeneity in RFMN technology and treatment protocols. Devices used included the Sylfirm/Sylfirm X (VIOL, Gyeonggi-do, Korea), Secret (Ilooda, Gyeonggi-do, Korea), INTRAcel (Jeisys, Seoul, Korea), Forma (InMode, Irvine, CA), and Intensif (EndyMed, Freehold, NJ), among others.^{4-7,10,11,13-15} The number of treatment sessions ranged from 2 to 10, administered at intervals of 2 to 4 weeks, with needle depths ranging from a superficial 300 μm to 2.0 mm, often titrated to mild erythema as the endpoint. A dominant theme across the studies was the use of RFMN in combination therapy. This included concurrent applications of topical agents, such as tranexamic acid or cysteamine, immediately postprocedure, use alongside conventional systemic treatments, such as oral tranexamic acid,⁴ or in combination with a low-fluence Q-switched Nd:YAG (QSNY) laser in the same session.^5,7,13,14,16 One study evaluated a novel home-based RF device.¹²

The primary outcome measure across all studies was the change in the Melasma Area and Severity Index (MASI) or modified MASI (mMASI) score. This was consistently supplemented by objective colorimetry using devices such as the Mexameter MX18 to measure melanin and erythema indices, as well as by standardized digital photography. Several studies incorporated patient-reported outcomes, including satisfaction and pain visual analog scales (VAS).^5,12 A key strength of a subset of studies was the inclusion of histological and immunohistochemical analyses, providing mechanistic insights into the effects of RFMN on dermal remodeling and senescence.^5,10,11,16 Follow-up periods ranged from short-term assessments at 2 weeks to more extended observations of 6 to 8 months posttreatment.^4,6

Common limitations observed across the study pool include relatively small sample sizes, with most studies enrolling 30 or fewer participants, and follow-up durations that may be insufficient to evaluate long-term efficacy and relapse rates. Although several RCTs employed blinded outcome assessment to mitigate detection bias, the nature of the intervention often prevented blinding of practitioners and patients, presenting a potential source of performance bias.^4,6,7 Furthermore, industry funding and device provision were reported in several studies, a factor that must be considered when interpreting the reported results.^5,11,12

Therefore, a detailed summary of the characteristics and extracted data from the 12 included studies is provided in Table 2. To facilitate direct comparison of treatment protocols with clinical outcomes, the key parameters, efficacy results, and safety findings are synthesized in Table 3.

Table 3.

Synthesis of Treatment Protocols, Efficacy, and Safety Outcomes

Study (author, year)	RFMN device and key parameters	Combination therapy	Primary efficacy outcome	Key safety findings
Han et al (2024)4	Sylfirm X; depth: 0.3 and 0.8 mm; Levels 4-6 (PW2); monthly maintenance (6 months)	Oral TA + TCC (initial 2 months)	Sustained ΔL* on treated side; 63.6% relapsed on untreated side at 6 months	Mild transient erythema/pain (<30 min); no PIH or scarring
Jung et al (2019)5	Secret; 1.0 mm, 50% intensity; 5 sessions	Low-fluence QS Nd:YAG laser	53.0% ↓ in Mexameter score (vs 39.2% laser alone)	No remarkable side effects; mild pain (VAS: 3.40)
Kwon et al (2019)14	Secret; 0.5-1.0 mm; 20-30 intensity; 10 sessions	Low-fluence QS Nd:YAG laser	ΔmMASI: 2.9 (vs 1.8 laser alone)	Lower RH/MH rate (18% vs 29% laser alone), mild pain
Park et al (2022)17	Pulsed type; 1.2-1.5 mm; 1.39-1.59 J/cm2; 5 sessions	None (monotherapy)	MI ↓ by 21.2% (melasma subgroup); IGA >26% improvement in 90.2%	Immediate erythema/edema (resolves 1-2 h); no dyspigmentation
Lee et al (2021)16	Sylfirm X; 300 μm depth; Levels 4-6; 5 sessions	Low-fluence QS Nd:YAG laser	Significantly greater ↓ in hemi-MASI and MI vs laser alone	Much less pain/erythema vs deeper FMR, well tolerated
Gulfan et al (2022)6	SYLFIRM; 1.5 and 0.8 mm (multipass); Level 2; 3 sessions	Polynucleotides (vs saline)	Significant ↓ in mMASI and MI for both sides at 6 months; no between-side difference	Mild transient erythema; low pain (VAS: 2.0); 10% recurrence rate
Tsai et al (2025)7	Sylfirm; 1.5 mm; Level 2; 4 monthly sessions	In-office and home-based cysteamine	Greatest mMASI ↓ with full combo (in-office + home cysteamine + RFMN)	Mild erythema (20%-27%), scaling, and rare allergic reaction
Akerman et al (2025)13	Intensif; 1.5 mm, 14 W, 50 ms; 4 sessions	Topical 4% tranexamic acid	mMASI ↓ by 31% in 3 months; 93% of patients improved	Mild transient erythema/edema; well-tolerated pain (VAS: 3.5).
Kwon et al (2021)10	Forma (noninvasive); 43°C, 62 mJ; 3 sessions	None (monotherapy)	MI ↓ by 13.7% at week 9; histological dermal improvement	Transient erythema (minutes); no PIH or burns
Kim et al (2019)11	SYLFIRM; 1.5 mm; Level 2; 5 sessions	None (monotherapy)	Increased L* value; ↓ p16INK4A + fibroblasts	Mild pain, transient erythema
Chen et al (2025)9	INTRAcel; 1.5-2.0 mm, 12.5 W; 2 sessions	None (monotherapy)	No significant change in MASI or MI for the melasma subgroup	Transient erythema, irritation, tightness (resolved <7 days)
Zhang et al (2025)12	ARF001 (home based); thrice weekly for 4 weeks	7% Arbutin cream	mMASI ↓ by 25.6% at week 8; MI ↓ by 22.8%	No adverse events reported; well tolerated

Comparative table detailing the specific RFMN treatment parameters (device, needle type/depth, energy, number of sessions) used in the included studies, alongside the corresponding reported efficacy outcomes (eg, reduction in MASI/mMASI, melanin index) and safety outcomes (eg, adverse events, incidence of PIH). IGA, Investigator Global Assessment; MASI, Melasma Area and Severity Index; MI, Melanin Index; mMASI, modified MASI; PIH, postinflammatory hyperpigmentation; RFMN, radiofrequency microneedling; VAS, visual analog scale.

Efficacy in Reducing Pigmentation and Disease Severity

The collective evidence indicates that RFMN is an effective intervention for reducing the severity of melasma, as measured primarily by reductions in the MASI and mMASI scores.^6,12,17 Efficacy was demonstrated across various device platforms and treatment paradigms.

Significant improvements in mMASI scores were reported in studies using RFMN as monotherapy, with notable decreases from baseline observed at all follow-up points through 6 months.⁶ A 25.6% reduction in mMASI was reported following a regimen of a home-based RF device combined with arbutin cream.¹² Furthermore, the efficacy of RFMN extended to refractory cases, with 1 study demonstrating significant improvement in the Investigator Global Assessment (IGA) in 90.2% of patients, along with a substantial reduction in the objective melanin index.¹⁷

A prominent subtheme is the role of RFMN as a highly effective combination partner, often yielding superior results compared with other standard modalities. This synergistic effect was most consistently demonstrated in combination with low-fluence QSNY laser. A significantly greater reduction in mMASI was achieved with combination therapy compared with QSNY laser alone, a result supported by both statistical graphs (Figure 1) and representative clinical photographs (Figures 2, 3) in that study.¹⁴ This finding was corroborated by split-face studies that demonstrated a significantly greater reduction in the melanin index on the combination side compared with the laser-only side with superior clinical improvement visually documented in representative photographs (Figure 1 in Jung et al).^5,16

Furthermore, RFMN proved effective in a maintenance role, preventing relapses. In a pivotal RCT, the half-face that received monthly maintenance treatments showed clinical improvement after conventional therapy was discontinued (Figure 2 in Han et al for representative clinical photographs).⁴ In contrast, the untreated half-face relapsed to near-baseline levels within 6 months, as quantitatively demonstrated by the decline in ΔL* values (Figure 3 in Han et al).⁴ This suggests RFMN acts on the underlying dermal environment to stabilize melasma and prevent recurrence, representing a novel and significant therapeutic strategy.

Safety and Tolerability Profile

Across the included studies, RFMN was consistently reported as well tolerated in Fitzpatrick skin types III-V. The most common immediate reactions were transient erythema and edema, which occurred in nearly all patients and resolved within hours to, at most, 7 days.^10,14,17 Procedural discomfort was usually rated as mild to moderate on VASs and was effectively managed with topical anesthesia alone.^5,6,11 Importantly, no study reported scarring, hypopigmentation, or long-lasting dyspigmentation.

Concerns about PIH were significantly lower than those typically linked to pigment-focused lasers. Several trials explicitly reported no cases of PIH during follow-up.^4,11,14,17 When pigmentary worsening occurred, it was limited to temporary rebound hyperpigmentation that improved with ongoing management: in the split-face study by Kwon et al, short-term rebound hyperpigmentation was seen in 18% of hemifaces treated with combined RFMN and low-fluence QSNY laser, compared with 29% on the laser-only side, and 2 other studies reported melasma recurrence in a minority of patients without permanent darkening.^6,12 Overall, these findings support a safety profile with minimal downtime and a low rate of severe or ongoing PIH, while noting that short-term rebound hyperpigmentation may occur in some patients.

Proposed Mechanisms of Action

The mechanistic evidence for RF-based treatments in melasma comes from histological and biomarker studies of both RFMN and a continuous, noninvasive RF device. Because these technologies differ in how and where energy is delivered, the effects of fractionated dermal coagulation through needles vs transcutaneous heating are summarized separately.

For RFMN, multiple studies have shown that treatment changes key dermal features involved in melasma development. Histological analyses showed a reduction in p16^INK4A-positive senescent fibroblasts after RFMN, along with increased procollagen 1 expression, indicating new collagen production and partial reversal of a senescent dermal environment.^13,15,17 RFMN also appears to strengthen the dermal–epidermal junction, with increased Type IV collagen and improved basement-membrane continuity, structures often disrupted in melasma. Critically, these dermal changes are linked to direct effects on epidermal pigmentation. Electron microscopy analysis of biopsy specimens reveals that RFMN can induce cytoplasmic shrinkage and melanocytic loosening of intercellular spaces, suggesting reduced melanocytic activity and facilitating trans-epidermal elimination of melanin.⁵ This is supported by immunohistochemical analysis of biopsy specimens showing significant posttreatment reductions in both Melan-A-positive melanocytes and Fontana silver-stained melanin within the epidermis (Figure 3B, C in Park el al for representative histology).¹⁷ Furthermore, RFMN downregulates key melanogenic paracrine signaling factors originating from the dermis, such as endothelin-1 (ET-1), basic fibroblast growth factor (bFGF), and stem cell factor, which are known to drive melanocyte hyperactivity.¹⁷ Therefore, RFMN appears to reduce visible pigmentation by combining direct cytoreductive effects on melanocytes with an indirect downregulation of the promelanogenic dermal microenvironment.

Additional data suggest that the anti-inflammatory and protective effects against light damage decrease in CD68⁺ macrophages, ET-1, and bFGF have been reported, along with increased heat-shock proteins and stromal-derived factor-1, which may aid in tissue repair and stress resilience.¹⁶ A shallow-depth protocol also suggests RFMN can lower UV-induced DNA damage and senescence markers (p16, p21) in epidermal keratinocytes, potentially reducing promelanogenic signaling.¹⁵

Complementary insight comes from a temperature-controlled, noninvasive RF device evaluated in melasma.¹⁷ Although it does not create needle-based microthermal zones, this technology also reduces markers of dermal senescence and improves Collagen IV expression. Supporting the broader concept that controlled RF-mediated dermal remodeling can ameliorate the promelanogenic microenvironment. However, these findings should not be extrapolated directly to specific RFMN treatment parameters; instead, they reinforce a shared mechanistic framework in which RF-induced remodeling of senescent, photo-damaged dermis contributes to durable pigment control.

Overall, the mechanistic data suggest that RFMN works beyond just targeting pigment. By reducing dermal senescence, strengthening the basement membrane, and modulating inflammatory and stress-response pathways, with direct evidence of reducing melanogenic activity and epidermal melanin, RFMN may address key drivers of melasma's chronicity.

Radiofrequency Microneedling (RFMN) as a Synergistic and Adjuvant Therapy

The evidence consistently underscores that RFMN is most effectively used as part of a combined treatment strategy, functioning both as a primary biostimulator and as a potent adjuvant that enhances the efficacy of other therapeutic agents.

One of the most compelling applications is its combination with laser therapy. Notably, pairing RFMN with a low-fluence QSNY laser consistently outperformed laser treatment alone across several studies.^5,14,16 The proposed explanation for this synergy is persuasive: the laser effectively targets and fragments epidermal pigment, whereas RFMN concurrently remodels the promelanogenic dermal environment. Ultrastructural evidence supporting this mechanism, including melanocyte shrinkage and intercellular loosening, is provided by electron microscopy (Figure 2 in Jung et al).⁵ This dual-pathway approach not only improves efficacy but may also crucially mitigate the common risk of rebound hyperpigmentation that can affect laser-only protocols.¹⁴

The utility of RFMN as a drug-delivery enhancement system also holds significant promise, although the results are agent specific. The technique facilitates trans-epidermal delivery of topicals, such as tranexamic acid and cysteamine.^7,13 However, it is essential to note that not all combinations are equally effective. For instance, the addition of topical polynucleotides failed to provide a significant benefit over RFMN alone in a well-designed trial, suggesting that the choice of adjuvant topical is critical.⁶ On the other hand, a more complex regimen combining RFMN with both home-based and center-based cysteamine showed the most pronounced improvement, hinting at a potential dose-response relationship for specific agents.⁷

Perhaps the most innovative application of RFMN is in long-term maintenance. A RCT demonstrated a novel use for technology; instead of focusing on initial clearance, RFMN was used to preserve the results of conventional therapy.⁴ Their finding that monthly RFMN sessions successfully prevented relapses for 6 months provides valuable insight into long-term melasma management, positioning RFMN as a potential key to maintaining remission.

Patient-Reported Outcomes and Satisfaction

Beyond clinical metrics, patient-reported outcomes offer a key window into the real-world acceptability and impact of RFMN treatment for melasma. Available data, although not uniformly reported, paint a generally positive picture of tolerability and satisfaction, closely tied to the procedure's favorable safety profile and tangible results.

Tolerability emerged as a key strength. Through studies, patients consistently reported procedural pain as mild to moderate, typically rating it between 2.0 and 3.8 on a 10-point VAS, and found it easily managed with topical anesthesia.^5,6,13 Perhaps as importantly, the minimal downtime was frequently highlighted as a significant benefit. The rapid resolution of transient side effects, such as erythema and edema, often within hours to days, meant patients could return to daily activities almost immediately, a practical advantage that likely increased overall acceptance.^12,15

Satisfaction levels were generally high, particularly in studies that used RFMN in combination with other modalities. Patients often expressed a clear preference for combination therapy over laser treatment alone, reporting higher satisfaction scores when the 2 modalities were paired.^5,14 One study of a home-based device regimen reported that over 70% of participants were satisfied with their overall results.¹² However, 1 trial revealed a notable disconnect between objective measurement and patient perception. Despite significant improvements in mMASI scores, the patients’ own assessments did not reflect a statistically significant perception of improvement across all groups.⁷ This finding serves as an important reminder that patient satisfaction is multifaceted and may not be fully captured by physician-graded scales alone, being influenced by factors such as expectations, overall skin texture, and the burden of the treatment protocol itself.

In summary, the patient experience of RFMN is characterized by high tolerability and minimal interference with daily life. Although satisfaction is generally positive, its complex relationship to clinical improvement highlights a critical need for future studies to formally measure what matters to patients, such as their satisfaction, quality of life, and perceived improvement, alongside traditional physician-graded scales.

Confidence in Review Findings

The CERQual approach was used to assess confidence in each review finding. We have high confidence in several key conclusions. The finding that RFMN significantly improves melasma severity is supported by consistent, statistically significant improvements in MASI scores and melanin indices across all studies. Similarly, there is high confidence that RFMN has a favorable safety profile with a low risk of PIH, based on coherent adverse event reporting across studies in relevant populations (Fitzpatrick skin types III-V). The synergistic effect with QSNY laser also merits high confidence, as it is a direct, replicated result from robust comparative studies.

We have moderate confidence in 2 findings because of more limited evidence. The conclusion that RFMN's mechanism involves targeting dermal senescence is highly coherent but relies on a smaller subset of histological studies with methodological limitations. The finding that RFMN is effective as a maintenance therapy is powerful but is currently supported by a single, high-quality RCT, requiring further confirmation.

No findings were graded as low or very low confidence, indicating a reliable evidence base for the review's conclusions. A detailed summary of qualitative findings table is available in Appendix D.

DISCUSSION

This systematic review demonstrates that RFMN fundamentally redefines the approach to treating melasma, particularly in patients with darker skin phototypes. Unlike traditional laser therapies, which primarily target epidermal pigments and carry a significant risk of PIH, RFMN appears to confer its benefits through dermal remodeling. The consistent findings across diverse devices and protocols suggest that the mechanism of action, fractional dermal remodeling, is more critical than any specific device parameter, offering a versatile and effective treatment option.

The most distinguishing advantage of RFMN is its exceptional safety profile, particularly its notably low incidence of PIH, which was consistently reported across the included studies.^4,6,10,12-14 This finding, characterized by only transient erythema and edema and minimal downtime, stands in stark contrast to the established profile of fractional nonablative lasers.^5,10,12,13 This stark contrast positions RFMN as a potential first-line energy-based modality for a patient population that has historically had limited and high-risk options.^4,14 Its high patient tolerability further enhances its practicality, addressing significant barriers to treatment adherence.^5,6,10 However, this potential must be balanced against practical considerations of cost, the need for multiple sessions, and access to trained operators, which are current barriers to widespread adoption.

The evidence further solidifies RFMN's role as a synergistic partner. Its consistent superiority when combined with a low-fluence QSNY laser suggests a powerful dual-pathway strategy: the laser targets epidermal pigment, whereas RFMN stabilizes the unstable dermal foundation that drives melanocyte hyperactivity.^5,14,16 This synergy is likely key to mitigating the rebound hyperpigmentation that often plagues laser-only treatments.¹⁴ Furthermore, its utility in enhancing the transdermal delivery of topical agents like tranexamic acid, although efficacy is agent specific, this approach offers a versatile tool for personalized regimens.^7,13

Perhaps the most paradigm-shifting application of RFMN is its potential role as maintenance therapy. The protocol evaluated in a recent RCT is conceptually innovative.⁴ The study demonstrated that after achieving initial clearance with conventional agents, periodic monthly RFMN sessions effectively maintained clinical improvement and prevented relapse over 6 months. This approach proposes a shift from continuous, often irritating, topical therapy to a device-based strategy to sustain dermal homeostasis, moving the therapeutic goal from mere suppression of pigment to sustained remission.

These encouraging findings must be interpreted within the significant constraints of the current evidence base. The preponderance of small sample sizes and the lack of large-scale, multicenter RCTs limit the statistical power and generalizability of the results. The marked heterogeneity of devices and treatment protocols must also be considered when applying these findings to clinical practice. The included studies used different platforms (monopolar or bipolar systems with insulated or noninsulated needles), a wide range of energy settings, pulse durations, penetration depths, tip configurations, and session numbers, and in several cases combined RFMN with topical bleaching agents or other energy-based devices. This variability complicates direct comparisons between studies and makes it challenging to define evidence-based recommendations on optimal parameters, the number of sessions, or ideal candidates. The available descriptions of device settings and protocols across the included trials, therefore, provide helpful guidance and illustrative examples but should not yet be regarded as prescriptive, standardized treatment regimens. Although industry funding is common for device studies, its presence here requires a considered interpretation of the positive results.^5,11,12 Finally, the observed dissociation between objective clinical scores and patient-reported perceptions underscores the need for future studies to incorporate validated patient-centered outcome measures to capture the treatment's impact on quality of life fully.

Implications and Future Directions

The findings of this review have direct implications for clinical practice, suggesting RFMN should be considered a first-line energy-based option for melasma, especially in patients with Fitzpatrick skin types III-V. However, to translate these promising results into definitive clinical guidelines, future research must address several critical gaps. Priority should be given to large, well-designed, multicenter RCTs that directly compare RFMN with other standard active treatments, such as oral tranexamic acid or triple combination cream. Furthermore, dose-finding studies are essential for establishing standardized, optimized treatment parameters across different devices and patient populations. Future trials must also incorporate more extended follow-up periods exceeding 12 months to truly assess the durability of the treatment response and long-term relapse rates. Finally, research should integrate correlative clinical-histological endpoints and validated patient-reported outcome measures to comprehensively evaluate both efficacy and the patient experience.

Publication Bias and Selective Reporting

The potential for publication bias was assessed narratively. A formal statistical evaluation using funnel plots was not feasible because of significant clinical heterogeneity in treatment protocols and outcomes across the included studies.

The search was restricted to English-language publications. Although this may introduce language bias, the consistent, positive findings for both efficacy and safety replicated across multiple independent studies from diverse geographic regions strengthen the credibility of the core conclusions. The primary concern remains the universal limitation of unpublished negative studies. However, the convergence of results from this body of literature indicates a reliable treatment effect for RFMN in melasma management.

Sensitivity Analysis

Because of the qualitative nature of the synthesis and significant clinical heterogeneity, a traditional statistical sensitivity analysis was not feasible. Instead, we assessed the strength of the review's key findings narratively.

The overall synthesis proved to be strong. The central conclusions, significant efficacy in reducing pigmentation and a notably low incidence of PIH, were consistent when examining only the studies with the lowest risk of bias. These findings remained consistent across different device types and study designs.

In contrast, the evidence supporting the proposed mechanism of action (targeting cellular senescence) was less robust, as it was derived from fewer studies using specialized methodologies. This indicates that although the core clinical outcomes are reliable, the underlying mechanistic evidence requires further validation.

Limitations and Future Perspective

This review has some limitations that should be considered when interpreting the findings. In addition to the relatively small, mainly single-center samples, follow-up periods were generally short for a chronic, relapsing disease such as melasma. In several studies, outcomes were assessed within 4 to 8 weeks of the last session, and in 1 trial as early as 2 weeks, which may not fully capture the long-term stability of response. The evidence base also shows some typical methodological constraints of emerging interventions, such as variable reporting of randomization and allocation procedures, limited blinding of outcome assessors, and inconsistent use of validated, melasma-specific patient-reported outcome measures. Information on concomitant skincare, photoprotection, and maintenance strategies was not always detailed, despite their potential influence on outcomes. Taken together, these factors suggest that although the available data support RFMN as a safe and clinically useful option in appropriately selected patients, the conclusions should be interpreted with appropriate caution and viewed as a foundation for future, more definitive studies.

Proposed Clinical Treatment Protocol

Based on the qualitative synthesized evidence from this review, a conjectural yet evidence-informed protocol for treating melasma with RFMN, particularly in Fitzpatrick skin types III-V, can be proposed. This approach positions RFMN primarily as an adjuvant and maintenance therapy, targeting the dermal microenvironment implicated in melasma's chronicity.¹⁶ An initial series of 3 to 5 monthly sessions is a common, effective framework.⁶ Needle depth should be tailored: a superficial depth of 0.3 to 0.5 mm specifically targets senescent keratinocytes at the epidermal–dermal junction and is associated with significantly better tolerability, whereas a deeper setting of 1.5 to 2.0 mm may be used for broader dermal remodeling, with energy titrated to immediate, mild erythema.¹⁶ The strongest evidence supports combining RFMN with a low-fluence QSNY laser in the same session, a regimen consistently shown to produce superior pigment reduction compared with laser therapy alone and potentially mitigate rebound hyperpigmentation.^5,16 For maintenance and relapse prevention, a critical challenge in melasma management, the evidence suggests that periodic (eg, quarterly) RFMN sessions can help sustain clinical improvement after initial clearance.⁹ Throughout, a favorable safety profile with transient erythema and minimal downtime is expected, although strict, lifelong photoprotection remains the non-negotiable cornerstone of any melasma therapy.⁵ This protocol is a synthesis of heterogeneous studies and is proposed as a practical framework for clinicians and as a hypothesis for future standardized trials.

CONCLUSIONS

Current evidence suggests that RFMN is a promising energy-based option for melasma, particularly in patients with darker phototypes and in those for whom pigment-targeted lasers have failed or are considered too high risk for PIH. Its favorable safety profile, minimal downtime, and mechanistic plausibility as a dermal-remodeling strategy support its use as part of an individualized, multimodal approach rather than as a stand-alone solution. Nevertheless, given the small, heterogeneous studies and short follow-up periods available to date, RFMN cannot yet be recommended as a first-line energy-based modality. Adequately powered, well-designed trials with standardized protocols, longer follow-up, and robust patient-reported outcomes are needed before definitive clinical recommendations can be made.

Supplemental Material

This article contains supplemental material located online at https://doi.org/10.1093/asjof/ojag075.

Disclosures

Dr Kumar head of Global Medical Affairs, Jeisys Medical Inc. (Seoul, Republic of Korea). All other authors declare no personal conflicts of interest.

Funding

Jeisys Med Inc., Seoul, Republic of Korea, funded the APC for the manuscript.