Radiofrequency (RF) skin tightening: how it works and its limits

How does RF treatment work?

RF treatment is classified as a physical biostimulation that uses electromagnetic waves to raise the temperature of tissue ^[1]. Even devices that go by the same name differ greatly in energy, wavelength, and handpiece design, and for some devices the treatment method is only partly defined ^[1].

A 2022 systematic review pooled the results of 354 patients treated in 21 studies, and although the type of device and its settings varied widely between studies, the treatment temperature was relatively consistent, between 38 and 44°C ^[3]. Another systematic review of face and neck treatment observed changes in the tissue after treatment, including a healing response along with the formation of new collagen (neocollagenesis) and elastic fibers ^[2].

However, it has been pointed out that the explanation that thermal injury produces the treatment effect is still a hypothesis that needs further discussion, and that terms such as "nonsurgical" and "nonablative" are also open to question ^[1].

Types of devices and how they differ

RF devices are divided by how the electric current flows into monopolar and bipolar or multipolar types, and the way energy spreads through the tissue differs by type ^[1]. A 2014 review assessed bipolar and multipolar devices as an option with less downtime and less pain than monopolar devices or other nonablative devices ^[4].

Radiofrequency microneedling, which delivers RF energy directly into the skin through very fine needles, is also widely used. This method adjusts how deep the needles go and the target temperature, and it is used to treat mild to moderate wrinkles and sagging on the face and neck ^[5]. Minimally invasive RF devices that do not remove skin, such as fractional, microneedling, and temperature-controlled devices, have been used on their own or as maintenance treatment after surgery ^[6].

Among the studies included in the 2022 systematic review, fractional RF was used most often, followed by nonablative RF ^[3].

What results to expect

A 2022 systematic review of RF treatment of the face and neck examined 121 publications and summarized that RF treatment improved skin laxity, elasticity, and the overall cosmetic condition of the skin ^[2]. Studies that used objective measurements also reported a lifting effect, improved elasticity and collagen, and fewer wrinkles ^[2].

However, satisfaction was higher among people who were hoping for a moderate degree of improvement ^[2]. That is why it is important to agree with your doctor before treatment on how much change you can expect.

In a 2021 review of 42 relatively high-quality studies of RF microneedling, 14 dealt with skin rejuvenation ^[7]. The authors considered that dermal remodeling and collagen production progress slowly, so the skin continues to improve even 6 months after treatment, and summarized that the treatment can be repeated and has been used safely in people with darker skin tones ^[7].

Side effects and precautions

The 2022 systematic review listed the main temporary side effects as discomfort, pain, redness (erythema), pigmentation, scabbing, swelling, edema, a purplish appearance of the skin, and acne-like breakouts ^[3].

Another systematic review of face and neck treatment found that RF treatment was generally safe, but reported that one patient developed a fistula (an abnormal channel in the tissue) in the neck ^[2]. The same review also reported a loss of facial fat volume after RF treatment ^[2]. If you are concerned about having a thin face, it is a good idea to discuss this during your consultation.

Results depend as much on patient selection and the practitioner as on the device. It has been stressed that appropriate patient selection, a thorough explanation, and treatment by an experienced doctor are important for a satisfying result ^[4]. It has also been pointed out that the treatment method needs to be adjusted to the device and the patient, and that the possibilities and limits of each device need to be understood ^[1].

How much evidence is there?

The evidence for RF treatment is still uneven. The 2021 review started from the concern that the effectiveness and safety of RF microneedling, and where it stands compared with other energy-based devices, were unclear ^[7]. The 2014 review also stated that larger studies are needed to obtain data on newly introduced devices ^[4].

The fact that the type of device and its settings varied widely between studies also makes the results difficult to compare ^[3]. For these reasons, it is difficult to say for certain that any one device is better than another, and no established standard for the number of treatments or the interval between them could be found in the research summaries reviewed for this article.

What to check during your consultation

RF treatment does not involve cutting or removing skin, but results and recovery vary from person to person depending on the condition of the skin, the device, and its settings. It is a good idea to check the following during your examination.

• The type of device to be used (monopolar, bipolar or multipolar, or microneedling) and why it was chosen
• Whether the degree of your sagging is within the range treatment can be expected to address
• The temporary reactions and recovery time to expect
• What to consider if you have little fat in your face
• When results appear and whether additional treatments are needed