Dual-frequency noninvasive monopolar radiofrequency was associated with statistically significant improvement in facial laxity and lower face lifting at 30 and 90 days, with 92% of the treated patients rated as improved or better at 90 days and no persistent adverse events, according to a prospective multicenter study.
In the per-protocol population of 39 patients, clinician-scored Global Aesthetic Improvement Scale (GAIS) response rates of 3 or higher were achieved by 85% (n = 33) of the participants at 30 days and 92% (n = 36) of them at 90 days following the final treatment. The responder rates exceeded a predefined 70% reference proportion using a one-sided exact binomial test. Mean GAIS scores increased from 3.26 at 30 days to 3.46 at 90 days.
Patient-reported satisfaction was concordant. On a 6-point patient satisfaction score, 80% (n = 31) of the participants reported scores of 4 or higher at 30 days and 85% (n = 33) of them reported these scores at 90 days.
Study Design and Treatment Parameters
The Institutional Review Board–approved study enrolled 39 patients (37 female, 2 male) aged 28 to 70 years (mean age = 54.4 years) across four US sites. Fitzpatrick skin types I through IV were represented. The patients underwent two treatment sessions spaced 4 weeks apart, although the protocol allowed up to three sessions.
The investigational device delivered radiofrequency energy at 6.78 MHz for superficial-to-intermediate dermal heating and 2.0 MHz to support deeper subdermal heating. Treatments were administered at shallow, middle, or deep settings based on facial zone and treatment goals. Adjustable cryogen cooling and automatic shutoff at surface temperatures above 43° C were incorporated.
Across the sessions, total shot counts ranged from 300 to 677 (mean = 568.8), and total delivered energy ranged from approximately 28,739 J to 92,996 J (mean = 56,391.2 J), corresponding to a mean of 101 J per shot. Mean procedural pain was 4.2 on an 11-point numerical rating scale without anesthesia.
Safety and Clinical Assessments
No long-lasting adverse events were reported. Mild erythema and edema occurred and resolved without treatment.
The assessments were based on standardized clinical photography at baseline and at 30 and 90 days following the final treatment. GAIS evaluations were performed by the treating researchers and were not blinded; independent blinded photographic review wasn't conducted. No adjustment for confounders or repeated-measures modeling was performed.
Limitations
The researchers noted several limitations, including the absence of a control or comparator arm, lack of blinding, and follow-up limited to 90 days. Tissue-level depth of effect wasn't directly measured in humans, and inferences regarding deeper structural targeting were based on preclinical porcine data. The small sample size precluded meaningful subgroup analyses and limited generalizability, particularly to male patients and those with Fitzpatrick skin types V and VI.
“[D]ual-frequency [noninvasive monopolar radiofrequency] using depth-dependent settings was associated with short-term improvement in the clinical appearance of facial wrinkles and laxity, high patient satisfaction, and no persistent adverse events through 90 days after the final treatment,” noted lead study author Robert A. Weiss, of the Maryland Laser, Skin, and Vein Institute, and colleagues.
Cynosure Lutronic supplied the investigational device and related materials and provided limited research funding to participating sites but had no role in study conduct or manuscript preparation. The study authors reported no current financial relationships, none within the previous 3 years with any organizations that might have an interest in the submitted work, and no other relationships or activities that could be perceived as influencing the study.
Source: Cureus
