Factors that influence tear meniscus area and conjunctivochalasis: The Singapore Indian eye study

Purpose: Assessment of tear film and conjunctiva is critical to define presence and severity of ocular surface disease. We aimed to characterize tear meniscus area (TMA) and conjunctivochalasis by anterior segment optical coherence tomography (ASOCT) in population-based patients and identify potential factors associated with low TMA and severe conjunctivochalasis.

Methods: Study subjects were enrolled from The Singapore Indian Eye Study, a population-based study of Asian Indian in Singapore. Imaging with ASOCT was performed on three ocular regions (nasal, central and temporal). TMA was obtained by measuring the cross-sectional area of the inferior tear meniscus. Severity of conjunctivochalasis was quantified by measuring the conjunctivochalasis ratio (CCR), the ratio of area of redundant conjunctiva to the TMA. Ocular symptoms and demographic factors were assessed by standardized questionnaires.

Results: A total of 403 participants (52.9% women) 40 years of age and older were included. TMA centrally was 2818 ± 5308 pixel². Female sex and the presence of meibomian gland dysfunction (MGD), but not older age, were associated with a lower TMA (p = 0.031, p = 0.031 and p = 0.956 respectively). In this population, 9.2% had severe conjunctivochalasis (CCR>0.7) whereas 39.0% had mild to no conjunctivochalasis (CCR≤0.3). Conjunctivochalasis was more severe in temporal, followed by nasal and central sections. Older age was associated with severe conjunctivochalasis (p < 0.001).

Conclusion: MGD and female gender were associated with lower TMA, while older age was associated with increased severity of conjunctivochalasis. Objective measurement of TMA and CCR using ASOCT imaging may be useful in the assessment of tear volume and ocular surface tear function.