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

<b><i>Purpose</i></b>: 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. <b><i>Methods</i></b>: 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. <b><i>Results</i></b>: 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&gt;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 <b><i>Conclusion</i></b>: 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.

**研究目的**：评估泪膜（tear film）与结膜（conjunctiva）状态，对明确眼表疾病（ocular surface disease）的存在及严重程度具有关键意义。本研究旨在基于人群的患者队列中，借助眼前节光学相干断层扫描（anterior segment optical coherence tomography, ASOCT）对泪河面积（tear meniscus area, TMA）与结膜松弛症（conjunctivochalasis）进行特征分析，并筛选与低泪河面积、重度结膜松弛症相关的潜在影响因素。

**研究方法**：研究受试者招募自新加坡印度裔眼部研究（The Singapore Indian Eye Study），该项研究为针对新加坡亚裔印度裔人群的人群队列研究。采用眼前节光学相干断层扫描（ASOCT）对鼻侧、中央、颞侧三个眼部区域进行成像。通过测量下泪河的横截面积计算得到泪河面积（TMA）。结膜松弛症的严重程度通过结膜松弛症比值（conjunctivochalasis ratio, CCR）进行量化，该比值为冗余结膜面积与泪河面积的比值。通过标准化问卷评估受试者的眼部症状与人口统计学特征。

**研究结果**：最终纳入403名40岁及以上的受试者，其中女性占比52.9%。中央区域的泪河面积为2818±5308像素²。女性性别与睑板腺功能障碍（meibomian gland dysfunction, MGD）的存在均与较低的泪河面积相关，而年龄增长与泪河面积无显著关联（分别对应p=0.031、p=0.031与p=0.956）。在本研究队列中，9.2%的受试者存在重度结膜松弛症（CCR>0.7），39.0%的受试者存在轻度至无结膜松弛症（CCR≤0.3）。结膜松弛症的严重程度依次为颞侧最高，其次为鼻侧与中央区域。年龄增长与重度结膜松弛症相关（p <

**结论**：睑板腺功能障碍与女性性别均与较低的泪河面积相关，而年龄增长则与结膜松弛症的严重程度升高相关。借助眼前节光学相干断层扫描（ASOCT）成像对泪河面积（TMA）与结膜松弛症比值（CCR）进行客观测量，或可用于泪液体积与眼表泪液功能的评估。