Radiofrequency to Treat Photoaging

Radiofrequency facial rejuvenation: evidence-based effect.

el-Domyati M, el-Ammawi TS, Medhat W, Moawad O, Brennan D, Mahoney MG, Uitto J.

J Am Acad Dermatol. 2011 Mar;64(3):524-35.

• Lots of electric and laser based devices are promoted as being efficient in rejuvenation. This Egyptian prospective study shows clinically and histologically in a tentatively scientific manner an effect for the application of monopolar radiofrequency (RF) in rejuvenation for photoaging.

Methods:

• In this study 6 volunteers (mean: 51.1 years old +/- 5.5 years) with mild photoagaing with phototypes of Fitzpatrick III & IV as well as Glogau class I and II wrinkles were treated for 3 months (6 sessions at 2 week intervals).  The RF generator produced a 6MHZ alternating current (and was used 90 minutes after application of a 5% lidocaine cream). Treatment at each session was done in 5-8 passes, the first two at 150 Joules (J) and the third one at 200 J. Photographic documentation as well as skin biopsies were performed at the beginning and end of the treatment, as well as 3 months after the last treatment.
• On histology quantification of elastin, collagen I and III, and new collagen were done histometrically and by histochemistry

Results:

• Comparing baseline to 3 months after the last treatment, Clinically (by the volunteers, 2 doctors and 2 observers) showed 35-40% improvement in tightening, 30-35% improvement in skin texture, 40-45% improvement in rhytides (all statistically significant). One volunteer developed erythema and transient hyperpigmentation.
• Comparing baseline to 3 months after treatment, there was a statistically significant increase in:

1. increase in epidermal thickness (from 62.7μm (+/- 2.4) to 79.5μm (+/- 9.8) (also measured for the granular layer and development of the rete ridges)
2. increase of the collagen band in the dermis from 9.8μm (+/- 3) to 15.6μm (+/-2.3)
3. increase of dermal collagen I (percentage of dermis where collagen I is present: from 65.8% (+/- 4.7) to 81.2% (+/- 4.5)
4. increase of dermal collagen III (percentage of dermis where collagen III is present: from 60.9% (+/- 2.5) to 73.6% (+/- 4.8)
5. increase in new dermal collagen (picrosirius red staining: yellow-orange birefringence) (percentage of dermis where new collagen is present: from 15.3% (+/- 4.3%) to 26.9% (+/- 3.7)
6. decrease in elastin (percentage of dermis where elastin is present)(from 53.7% (+/- 7.4) to 42.2% (+/- 3.6).

• The number of patients enrolled is low and was only conducted in one centre, but it does show the beneficial effect of Monopolar Radiofrequency in the treatment of photoaging at least in its mild to moderate forms.

Unfortunately the term “blinded” in the methodology is unclear; it is very difficult to compare collagen quantification differences by using immunohistochemistry. Also the picrosirius staining appear stronger on the after treatment pictures, due to increased holes in the dermis. However these comments are of little value as rigorous peer-review lead to acceptance and publication in the Journal of American Academy of Dermatology.