Prevalence of Anterior Extensions of the Parotid Gland and Sonographic Characterization of the Accessory Parotid Gland

This study aimed to determine the presence of anterior extensions of the parotid gland (AEPG) and to characterize the sonographic features of the accessory parotid gland (APG) using ultrasonography. A total of 230 individuals (460 parotid glands) were included in the study. Glandular tissue anterior to the main parotid gland (MPG) was classified as a facial process (FP) when continuous with the MPG or as an APG when no visible continuity was present. The term AEPG was used to describe either an FP or an APG. The APG was characterized in terms of echogenicity, parenchymal echotexture, margin definition, and morphometric parameters. The prevalence of APG, FP, and AEPG was 9.8%, 33.9%, and 43.7%, respectively. Sex was significantly associated with AEPG presence, with a higher proportion of males ( p = 0.022). Body mass index (BMI) showed positive correlations with APG superoinferior dimension and volume and a negative correlation with the APG–main parotid gland distance (all q < 0.05). All identified APGs were isoechoic compared with the MPG parenchyma. No significant association was found between APG margin and parenchymal characteristics and sex, BMI, or age. The consistent morphological features of APGs identified on ultrasonography may facilitate their recognition and help avoid misinterpretation during imaging of the parotid region.