目的：研究短时间内大量摄入咖啡因对健康成年人眼表泪膜动力学的影响。方法：受试者为12名健康的成年人(20~30岁)，没有既往眼表疾病史。受试者在恒定的常规条件下摄入5.0 mg/kg咖啡因(取咖啡粉剂按浓度预调)。在摄入咖啡因前后2 h进行泪膜参数评估和泪液收集。受试者接受了泪河高度、泪膜破裂时间、Schirmer I试验、眼压和平均脂质层厚度的测量。结果：摄入大量咖啡因后，泪河高度、泪膜破裂时间和眼压的检测值显著增加，而平均脂质层厚度的检测值与摄入咖啡因之前相比显著下降。摄入咖啡因后，Schirmer试纸收集的泪液量改变无明显统计学意义，未观察到咖啡因对泪液分泌的影响中的性别差异。结论：在大量摄入咖啡因后，眼表泪液动力学发生显著改变且咖啡因可以刺激健康的非干眼受试者的泪液分泌。
Objective: To investigate the effects of high caffeine intake in a short period on tear film dynamics in healthy adults. Methods: The participants were 12 healthy adults (20–30 years old) with no history of ocular surface disease. Participants were given 5.0 mg/kg caffeine (preset the coffee powder according to the concentration)under constant routine conditions. Tear film parameters were assessed and tear collection was performed 2 h before and after caffeine intake. The tear meniscus height, non-invasive tear break-up time, Schirmer I test, intraocular pressure and average lipid layer thickness were all measured after a large amount of caffeine intake. Results: The tear meniscus height, non-invasive tear break-up time and intraocular pressure were significantly increased after caffeine intake, while the average lipid layer thickness was significantly lower than that before caffeine intake. The amount of tear fluid collected by Schirmer’s I test paper was not statistically significant, and there was no gender difference in the effects of caffeine on tear secretion. Conclusion: After high caffeine intake, ocular tear dynamics are significantly altered and caffeine can stimulate tear secretion in healthy, non-dry-eyed subjects.
泪膜的不同组成成分通过相互作用共同维持眼球表面的湿润，从而维持眼部健康。当这些组成成分出现病理性改变，将会不同程度的影响泪膜稳态，从而导致干眼的发生。而瞬目运动一定程度上影响着泪膜组成成分的分布，随着对干眼相关机制研究的逐步深入，以泪膜为导向的诊断(tear-film-oriented diagnosis，TFOD)的新概念被提出，并被逐渐被接受。我们可以通过泪膜破裂方式来确定眼球表面所缺乏的组成成分，并在此基础上对干眼进行诊断，从而定向补充泪膜缺失成分，重新恢复泪膜稳态。本文将着重分析瞬目、泪膜形成及泪膜破裂机制之间的关系，从而进一步明确泪膜定向诊断的新概念及发展方向。
Different components of the tear film work together to maintain the wettability of the ocular surface, thus maintaining eye health. When the pathological changes of these components occur, the tear film homeostasis will be affected to varying degrees, leading to dry eye. Blinking movement affects the distribution of tear film components to some extent. With the continuous development of research and understanding of the concept and mechanism of dry eye, new concepts of tear-film-oriented diagnosis (TFOD) have been gradually proposed and widely accepted. We can determine the components lacking on the surface of the eye through the tear film breakup patterns (BUPs). On this basis, dry eye is diagnosed, so as to replenish the lacking components of tear film directionally and restore the stability of tear film. This paper will focus on analyzing the relationship between blinking, tear film formation and tear film break-up mechanism, so as to further clarify the new concept and development direction of tear-film oriented diagnosis.
泪膜是覆盖于眼球表面的一层液体薄膜，从内而外分为黏液层、水液层和脂质层，每层成分的改变都会导致泪膜不稳定，进而导致干眼的发生。在研究泪膜破裂方式及相关泪液成分改变的基础上，学者Yokoi及其团队分别在2012年和2013年提出了有关干眼治疗和诊断的新概念，称为泪膜导向治疗(tear film-oriented therapy，TFOT)和泪膜导向诊断(tear film-oriented diagnosis，TFOD)，就是根据泪膜破裂模式(tear film break-up pattern，TFBUP)的不同，推断出相应的泪膜成分改变，补充不足的泪膜成分，这种诊疗方法目前正逐渐被接受。本文对不同泪膜破裂方式与泪膜成分改变的关系做了汇总分析，旨在为干眼的诊断和治疗提供更为科学实用的指导方案。
Tear film is a layer of fluid film covering the surface of eye global, which is divided into mucus layer, aqueous layer and lipid layer from inside to outside. The change of each layer composition will lead to tear film instability, resulting in the occurrence of dry eye. On the basis of numerous studies on the correlation between tear composition and tear film break-up patterns, Yokoi and his team proposed new concepts on the diagnosis and treatment of dry eye called tear film-oriented therapy (TFOT) and tear film-oriented diagnosis (TFOD) in 2012 and 2013. That is according to different tear film break-up patterns (TFBUP), so changes in tear film composition can be deduced and supplemented, and this diagnosis and treatment method is gradually being accepted. In this paper, we summarized and analyzed the relationship between different tear film break-up patterns and changes in tear film composition to provide a more scientific and convenient guidance program for the diagnosis and treatment of dry eye.
