Anthropometry of the External Ear in Korean Adults: A Multicenter Study

Background: Numerous anthropometric studies on the auricle have been conducted in diverse populations, and variations in ear morphology associated with age, sex, and ethnicity have been identified. This study aimed to establish standard anthropometric data for the external ear within the Korean adult population. Methods: This study included 631 subjects (331 males and 300 females) aged 20 to 92 years, who underwent three-dimensional computed tomography (3D-CT) of the face for various medical purposes at six hospitals in Korea. Soft-tissue landmarks on the ears and face were obtained from 3D-CT reconstruction images. Ear lobule types were classified into the following categories: tapering (≤ 69°), square (70–109°), and pendulate (≥ 110°). The classification was based on the angle between the base of the auricle and a line drawn from the superior otobasion to the inferior otobasion. Age correlations and differences according to sex were analyzed for all measured variables. The average ear length and width were compared with data from previously published reports on other ethnic groups. Results: Compared with females, males presented greater ear length, ear width, protrusion at the superaurale and tragal levels, and lobular length. All measurements were symmetric on both sides, except for the auricle distance from the inferior orbital rim (IOR). All length measurements (insertion/ear/conchal/lobular length), lobular width, and auricle distance from the IOR were positively correlated with age. The pendulate lobule type was the most prevalent configuration in both sexes, followed by the square and tapering types. Koreans had shorter ear lengths than Indians and Caucasians but longer ear lengths than Africans and Chinese individuals. Conclusion: Our age-specific auricular anthropometric data for Koreans will serve as a valuable reference for diagnosing congenital abnormalities and guiding surgical reconstructions in the Korean population.