Ethnic variation in deep lateral orbital anatomy and its implications on decompression surgery

Area of Science:

• Anatomy
• Anthropology
• Medical Imaging

Background:

• The deep lateral orbital wall, specifically the orbital trigone, plays a critical role in orbital structure and surgical approaches.
• Understanding ethnic variations in orbital anatomy is essential for safe and effective surgical interventions, particularly in decompression procedures.

Purpose of the Study:

• To quantitatively compare the dimensions of the deep lateral orbital wall (trigone) and orbital depth across different ethnic groups: Chinese, Malay, Indian, and Caucasian.
• To identify significant anatomical differences that may influence surgical outcomes.

Main Methods:

• A retrospective Computed Tomography (CT)-based study involving 20 subjects per ethnic group (Chinese, Malay, Indian, Caucasian), matched for gender and age.
• Measurements included deep lateral wall length, thickness, volume, and orbital depth, analyzed using specialized imaging software and statistical analysis.

Main Results:

• Indian subjects demonstrated significantly smaller trigone thickness and volume compared to Chinese and Malay subjects.
• Caucasian subjects also showed smaller trigone dimensions than Chinese and Malay subjects, though less pronounced than in Indian subjects.
• Indian subjects exhibited shallower orbital depths (both perpendicular and diagonal) compared to other ethnic groups.

Conclusions:

• Indian and Caucasian populations possess smaller orbital trigones, with Indian subjects also having shallower orbits.
• These ethnic-specific anatomical variations necessitate careful consideration during orbital decompression surgery to minimize complications.