Abstract
Purpose :
To compare the limbal structure and limbal epithelial thickness (LET) between a Chinese Han population and a population in the United States using anterior segment optical coherence tomography (AS-OCT).
Methods :
Sixty healthy Chinese subjects (109 eyes, group I) and 39 normal subjects in the United States (65 eyes, group II) were included in this observational comparative study. The central cornea and the superior, inferior, nasal, and temporal limbus of each subject underwent Fourier-domain AS-OCT. Corneal epithelial thickness (CET), the width of limbus, distance between the scleral spur and the thickest part of limbal epithelium (S-T), limbal epithelial area between scleral spur and the end of Bowman's layer (LEA) , the maximum LET and the mean LET were measured.
Results :
The width of limbus was 34.6%, 31.7%, 36.5%, and 34.0% greater in the superior, inferior, nasal and temporal limbus, respectively, in the US group than in the Chinese group. S-T and LEA were also significantly higher in all limbal quadrants in the US group (all P<0.001). The maximum LET and mean LET were 11% and 8.1% thicker at the nasal limbus and 8.1% and 6.0% thicker in the temporal limbus in the US group than in the Chinese group.
Conclusions :
Compared with the Chinese group, the US group had a wider limbus in all quadrants and thicker limbal epithelium in the nasal and temporal quadrants. Investigators conducting studies of the limbus and surgeons performing procedures with the limbal area involved should take into consideration of these anatomic differences.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.