Abstract
Purpose :
Asian ethnicity has been identified as a consistent risk factor for meibomian gland dysfunction (MGD) and dry eye disease, although the reasons for this are unclear. Blink completeness is believed to play a role in MGD development, and a link between a difference in blink completeness and meibomian gland drop out between Asian and Caucasian eyes in a study of age-matched young adults, supports this hypothesis. Whether meibomian gland drop out differences between Asian and Caucasian eyes exist from a much younger age is unknown. This study compared an age-matched paediatric Asian and Caucasian population to establish if changes in MG dropout and blink quality exist in childhood.
Methods :
Seventy age-matched paediatric participants (aged 5-17 years) were recruited. Tear film quality, dry eye symptomatology, and ocular surface characteristics, including percentage meibomian gland drop out and morphological characteristics, were evaluated in a single clinical session. Metrics were compared across different eyelid shapes; Asian single lid featuring no lid crease (ASL) (n=24), Asian double lid (ADL) (n=21), and Caucasian double lid (CDL) (n=25).
Results :
No significant intergroup differences in tear film quality, dry eye symptomatology or percentage meibomian gland drop out were observed (all p>0.05), except lid wiper epitheliopathy in the lower lid which was significantly greater in the ASL than the ADL group (p=0.011). Incomplete blinking was more common in the ASL and ADL groups than CDL group (both p<0.05). Gland drop out increased with age across all participants (R=0.3356, p=0.005) being negligible at age 5 years and rising to a median of 12% by 17 years of age. Gland morphology varied with ethnicity such that the Asian eyelids featured significantly more gland truncation than Caucasian lids (p=0.013) while the Caucasian lids exhibited more pronounced tortuousity (p<0.0001).
Conclusions :
Ethnic differences in meibomian gland drop out levels that are reported in early adulthood do not exist in childood. The higher incomplete blinking rate previously demonstrated to exist in adult Asian eyes is apparent from a young age and may be a factor in predisposing the Asian eye to MGD. Differences in eyelid tension may contribute to ethnic variations observed in gland morphology and warrant further study.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.