Abstract

Objectives: Typically, methods such as filler injections or fat grafting are commonly chosen to increase facial volume. However, as more patients seek natural results recently, I would like to introduce a method that utilizes an Energy-Based Device (HIFU) to achieve a natural increase in facial volume. Decreased medial cheek fat volume during aging leads to loss of a youthful facial shape. Increasing facial volume by methods such as adipose-derived stem cell (ASC) injection can produce facial rejuvenation. Introduction: High-intensity focused ultrasound (HIFU) can increase adipogenesis in subcutaneous fat by modulating cilia on ASCs, which is accompanied by increased HSP70 and decreased NF-κB expression. We evaluated the effect of HIFU on increasing facial adipogenesis in swine (n = 2) via modulation of ASC cilia. Expression of CD166, an ASC marker, differed by subcutaneous adipose tissue location. CD166 expression in the zygomatic arch (ZA) was significantly higher than that in the subcutaneous adipose tissue in the mandible or lateral temporal areas. Materials / method: HIFU was applied only on the right side of the face, which was compared with the left side, where HIFU was not applied, as a control. HIFU produced a significant increase in HSP70 expression, decreased expression of NF-κB and a cilia disassembly factor (AURKA), and increased expression of a cilia increasing factor (ARL13B) and PPARG and CEBPA, which are the main regulators of adipogenesis. All of these changes were most prominent at the ZA. Facial adipose tissue thickness was also increased by HIFU. Results: Adipose tissue volume, evaluated by magnetic resonance imaging, was increased by HIFU, most prominently in the ZA. In conclusion, HIFU increased ASC marker expression, accompanied by increased HSP70 and decreased NF-κB expression. Additionally, changes in cilia disassembly and length and expression of adipogenesis were observed. These results suggest that HIFU could be used to increase facial volume by modulating adipogenesis. Conclusion: Clinically, we recommend the application of low-energy HIFU (0.1-0.2J, dot-type, approximately 400-800J, 10 sessions per week) to the buccal fat pad and areas with localized volume deficiency. The buccal fat pad contains a rich source of stem cells, and M2 macrophage polarization is predominant in this region.