The Application of High-frequency Ultrasonic Imaging in Identifying Fillers in the Temporal Region.

Background: This study aimed to evaluate the ultrasonic manifestations of diversified corium fillers in the temporal region and to provide clinicians with suggestions for diagnosis and treatment.

Methods: The facial ultrasound images of 116 patients, including 110 women and six men, 20-61years of age, were analyzed at the Chinese Academy Medical Sciences and Peking Union Medical College from November 2014 to November 2021.

Results: We identified 48 cases of polyacrylamide, 31 cases of fat, 27 cases of hyaluronic acid, seven cases of hydroxyapatite, two cases of silicone oil, and one case of prosthesis. Polyacrylamide mainly showed irregular flocculent hypoechoic or fine punctate hypoechoic in ultrasound; it could be aggregated as a cystic hypoechoic area or diffused in the tissue space, and the probe could be pressurized to see the echo floating or dislocation flow. Fat mainly showed lobulated hypoechoic deposition with some hyperechoic linear intervals. Hyaluronic acid mainly showed an anechoic structure with a clear boundary, uniform internal echo, and no obvious blood flow signal. If diffused in the surrounding tissues, it was mainly characterized by anechoic or low-echo areas in the stratified tissues. Hydroxyapatite mainly showed strongly hyperechoic patch areas with posterior acoustic shadowing artifacts. Silicone oil was mostly found under the epidermis, showing a high echo in the form of clouds and causing unclear displays of deep tissue. Prosthesis showed hypoechoic prosthesis structure.

Conclusion: High-frequency ultrasound had a certain significance in the identification of the fillers of the temporal region.