Fascia of the facial area is contiguous between fat tissues of the subcutaneous and connective tissue layers and does not envelope the muscle surface like other parts of the human body. This structure is called the superficial musculoaponeurotic system (SMAS), which is accepted as an international anatomical terminology. This special structure is commonly used to pull facial muscles during plastic surgeries such as a face lift. Most reports regarding the facial subcutaneous tissue structure including SMAS are in the field of plastic surgery, and only a few studies from a morphological perspective has been reported. Since the facial fascia does not envelope the muscular surface layer which is different from the deep fascia found on the general skeletal muscle surface, a clear definition of this structure has not been established yet. The purpose of this study was to clearly identify the basic morphological structure of the subcutaneous tissue layer containing the SMAS three-dimensionally through a scanning electron microscope using dissected specimen rather than living subjects. Moreover, this study explores structural differences among seven aging facial areas; thereby further clarifying the properties of the structure and add clinical significance and considerations.

面部筋膜位于皮下脂肪组织和结缔组织层之间，不像人体其他部位那样包裹肌肉表面。这种结构被称为浅表肌肉腱膜系统（SMAS），它被接受为国际解剖学术语。这种特殊的结构通常用于在整容手术（如面部提升）期间拉动面部肌肉。包括SMAS在内的面部皮下组织结构的报道大多属于整形外科领域，仅从形态学角度进行的研究很少。由于面部筋膜不包覆肌肉表层，这与一般骨骼肌表面的深筋膜不同，因此对该结构的定义尚未明确。本研究的目的是通过扫描电子显微镜使用解剖标本而不是活体对象来清晰地识别包含 SMAS 的皮下组织层的基本形态结构。此外，这项研究探讨了七个老化面部区域之间的结构差异；从而进一步阐明结构的特性并增加临床意义和考虑因素。