RESUMO
BACKGROUND: Many consumers use cosmetic eye products to counteract age-related changes in appearance. Measurements of eyelid shape in Asian women have been reported in the frontal view or 45-degree profile only. The aim of this study was to describe morphological characteristics of the upper eyelid in Japanese and Chinese females from the frontal and profile aspects and examine morphological changes with age. MATERIALS AND METHODS: Standardized digital photographs of 772 Japanese and 346 Chinese women (15-79 years of age) were acquired in frontal and 90-degree profile aspects. Eleven upper eyelid parameters (e.g., width, length, depth, aperture, and curvature) were measured using image analysis to determine age-related changes and compare by ethnicity. RESULTS: Eyelid width, area between eyebrow and eyelid, and eyelid curvature were comparable for both ethnicities under age 40, but the aging effect was more pronounced in Chinese subjects. Eyelid height, depth, and upper eyelid aperture angle were also comparable for both ethnicities under age 40, but the aging effect was more evident in Japanese subjects. Upper eyelid incline angle, eye orientation, and upper eyelid protrusion angle changed comparably with age for both ethnicities. No prominent age-related changes were evident for eyelid length or area between eyebrow and eye with the eye closed. CONCLUSION: Upper eyelid morphology changes with age in Japanese and Chinese females, starting around 40 years of age. Ethnic differences are limited in younger age groups but become more prominent with age. The findings suggest that aging affects some upper eyelid features earlier than others.