Abstract
Purpose :
The tear film's lipid layer, often underexplored compared to aqueous and mucin layers, plays a critical role in ocular surface health. This comprehensive study investigates age-related variations in tear film lipid layer thickness (LLT), meibomian gland morphology, and ocular surface parameters in healthy individuals across different ages, aiming to establish normative reference values for precise clinical assessments.
Methods :
IRB-approved prospective cross-sectional study at LV Prasad Eye Institute, India, comprising 218 eyes (109 individuals) stratified by age groups (18-29, 30-39, 40-49, 50-59, and 60 above) according to DEWS II criteria for asymptomatic healthy individuals with a stable tear film (OSDI score 0-12, NIKBUT > 10 sec). Exclusions included a history of contact lens and drop usage ocular pathology affecting the tear film. Assessment utilized LipiView interferometer and Oculus Keratograph 5M for parameters like LLT, Non-invasive keratographic tear film break-up time (NIKBUT), tear meniscus height (TMH) schirmer's test without anesthesia, meibomian gland morphology(gland loss ) and function by MG expressibility)was scored secretion seen in all central 5 meibomian glands: 0, all glands; 1 (3–4 glands); 2 (1–2 glands); and 3 (no glands). Meibum quality is graded as 0 (clear) 1 (cloudy) 2 (cloudy with debris);3 (inspissated, toothpaste-like).
Results :
Age range of 18-77 (44.07 ± 14.62 SD), male and female (1:1). LLT decreased from 77.05±16.80 nm SD(18-29) to 71.66 ±22.97 nm SD(≥60). NIKBUT decreased from 14.29 ± 3.03s SD (18-29) to 10.93 ± 4.35s SD (≥60). Schirmer's test: 32.21 ± 4.68mm SD (18-29) to 21.8 ± 9.16mmSD (≥60). TMH 0.31 ± 0.09 mm (18-29) to 0.22 ±0.04mm SD (≥60). No gland loss was observed in the 18- 29 group (grade 0) increased to ≥60 age (grade 1, 2). No relationship between age and LLT (sqrt=0.017;p<0.001). While age shows a highly significant association with MGE (p < 0.001) and substantial variation in MGQ (p < 0.001).
Conclusions :
Our study underscores the importance of age-specific considerations for enhanced diagnostic precision in ocular surface assessments, which is crucial for refining diagnostic criteria. However, it's essential to note that gender and overall systemic health in the elderly may influence these findings, highlighting limitations that warrant exploration in future studies.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.