Scanning electron microscopic study on double and single eyelids in Orientals

Area of Science:

• Anatomy
• Ophthalmology
• Cosmetic Surgery

Background:

• The conventional theory attributes double eyelids in Occidentals to levator aponeurosis terminal insertion, contrasting with single eyelids in Orientals.
• Recent reports question this theory, suggesting other anatomical factors contribute to eyelid differences in Orientals.

Purpose of the Study:

• To investigate the precise anatomical direction of the levator aponeurosis in Oriental eyelids.
• To clarify the anatomical basis for single versus double eyelids in the Oriental population.

Main Methods:

• Utilized scanning electron microscopy (SEM) for detailed observation of Japanese eyelids.
• Performed three-dimensional, cross-sectional analysis to visualize the levator aponeurosis structure.

Main Results:

• Confirmed the presence of a levator aponeurosis branch running through the orbicularis oculi muscle in Oriental double eyelids.
• This specific branch, connecting to the levator aponeurosis, was observed similarly to Occidental eyelids but was absent in single eyelids.

Conclusions:

• The study identifies a key anatomical difference in Oriental double eyelids, involving a specific levator aponeurosis branch.
• This novel finding provides a crucial anatomical foundation for understanding and performing double eyelid surgeries in Oriental individuals.