Microneedle radiofrequency: comparable to CO2 laser, and adding it to a laser did not improve on the laser

A 2025 randomised split-face pilot study in China. Thirty subjects with facial atrophic acne scarring had each side of the face randomly assigned to non-insulated microneedle fractional radiofrequency (NIMFRF) or ablative fractional CO2 laser, one session each. VISIA imaging was taken at baseline and at 1, 2 and 6 months.

The results in order:

• Both showed comparable efficacy on atrophic acne scarring relative to baseline (p < .05).
• About 95% rated their improvement 'satisfied' or 'very satisfied'.
• Pain was more obvious on the CO2 laser side.
• Red area value, melanin index and erythema index increased significantly on the CO2 side.

The last line matters practically. Pigment and erythema measures rising on the CO2 side means the approach that removes the surface carries more downtime and more pigmentation risk. That weighs especially in darker skin.

The limits are clear too. The authors call it a pilot, it is 30 people, and each side received a single session. And the control here is again another device — not a comparison against no treatment.

The 2024 trial asks a good question. When two devices are each known to work, is alternating them better than using one?

The faces of twenty patients with atrophic acne scars were split: one side received non-ablative fractional laser (NAFL) alone, the other NAFL alternating with microneedling radiofrequency (MNRF). Four treatments at four-week intervals. Prospective, single-centre, double-blinded, split-face.

Ninety days after the final treatment:

• Both halves improved significantly from baseline on the acne scar assessment score (ECCA) (p < .001 for both).
• Average improvement at the final endpoint was 20–30% from baseline.
• No significant difference between the halves at any time point.

The authors' conclusion: both are safe and effective, but alternating NAFL and MNRF does not seem to be superior to NAFL alone.

How to read this matters. It does not mean microneedle radiofrequency does not work. It means no additional gain was demonstrated from adding it on top of a laser you are already doing.

The same structure appears on this site's tranexamic acid page: significant against placebo, not significant when added to existing treatment. 'Does it work' and 'is it worth adding' are different questions.

And hold onto the figure 20–30%. That is the average improvement after four sessions.

A 2025 systematic review collected studies of fractional radiofrequency microneedling used as monotherapy for acne scarring, searching up to July 2024.

Sixteen studies, 481 patients. The breakdown:

• Six prospective studies
• Six randomised clinical trials
• Three retrospective studies
• One comparative trial

The authors' conclusion, as written: fractional radiofrequency microneedling is likely an effective treatment for acne scarring when used as monotherapy. But further randomised controlled trials are needed to establish appropriate treatment parameters.

Two things to note.

First, the word 'likely'. Six of the sixteen are randomised; the rest have weaker control. The authors' hedge has a reason behind it.

Second, the open question has moved from whether it works to how to do it. Needle depth, power, exposure time, number of sessions, interval — none of these is settled, which also means a procedure with the same name can be performed under different conditions from clinic to clinic.