An Analysis of the Factors Influencing Forehead Soft-Tissue Thickness: An Ultrasound Study

Background A detailed understanding the anatomy of the soft tissue layers of the forehead can help guide clinical treatment, but to date there is a lack of large-scale and comprehensive research in this area. Objectives This study aims to evaluate the effects of age, gender, body mass index (BMI), and other factors on the thickness of the soft tissue layers of the forehead. Methods A total of 238 volunteers were examined using ultrasonography, and the thickness of each forehead layer was measured. The effects of age, gender, BMI, and region on the thickness of each layer of forehead were statistically analyzed using an analysis of variance. Results In men, the thickness of the skin, superficial subcutaneous tissue (SST), and frontalis muscle were significantly greater than those in women (skin: 0.95 vs 0.73 mm; SST: 0.75 vs 0.67 mm; frontalis muscle: 0.35 vs 0.25 mm), whereas the thickness of the deep subcutaneous tissue (DST) was significantly thicker in women than in men (1.26 vs 1.42 mm). An increased BMI was associated with increased thickness of the skin, SST, and DST. In addition, as age increases, the thickness of SST also increases. Conclusions Factors such as gender, age, BMI, and the left vs. right sides all affect the thickness of each forehead tissue layer. These findings can provide a treatment reference for the forehead region.