Surgical anatomy of the Chinese orbit.
OBJECTIVE
To describe the metric measurements and normal anatomic variants in Chinese bony orbits.


METHODS
Orbital osteology was studied in 194 orbits from 97 Chinese skulls. Morphologic observations and metric measurements were made to elucidate the variations of the orbital bony anatomy and to localize important fissures and foramina within the orbit. Sexual dimorphism and side asymmetry of orbital features were analyzed. Results were then compared with data from other populations.


RESULTS
The details of the orbital osteology in Chinese are described. Most orbital features show anatomic variations in terms of their existence, quantity, and location. Anatomic variants including quadruple and extrasutural posterior ethmoidal foramen are described for the first time. Side asymmetry and sexual dimorphism (male larger than female) are demonstrated in some orbital features. Compared with white and American populations, orbital measurements are generally smaller in Chinese, probably related to their smaller orbital size.


CONCLUSIONS
The Chinese orbital osteology demonstrates considerable variability. The newly described anatomic variants found on the posterior ethmoidal foramen may affect surgical procedures related to the medial orbital wall. Sexual dimorphism and ethnic variations of the orbital bony anatomy may affect surgical approach to orbital diseases in different populations.
Cheng
Andy C O
AC
Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong Eye Hospital, Hong Kong Special Administrative Region, Pokfulam, Hong Kong, China. acocheng@gmail.com
Lucas
Peter W
PW
Yuen
Hunter K L
HK
Lam
Dennis S C
DS
So
Kwok-Fai
KF
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019412:Anatomy, Cross-Sectional; D044466:Asian People / Q000208:ethnology; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009915:Orbit / Q000033:anatomy & histology*; D012727:Sex Characteristics