Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia.
Vision Sciences, Glasgow Caledonian University, Glasgow, Scotland, UK.
BMC Ophthalmol. 2023 May 22;23(1):226. doi: 10.1186/s12886-023-02977-3.
The study aimed to assess the efficacy of hydroxypropyl guar (HP) formulation (Systane) to protect tear film parameters under desiccating environment using protection and relief treatment modalities. The subjects were exposed to adverse environmental conditions using a Controlled Environment Chamber (CEC) where the relative humidity (RH) was 5% and the ambient temperature was 21 °C and screened for Tear break-up time (TBUT), Tear film evaporation rate (TFER) and lipid layer thickness (LLT) using the HIRCAL grid, Servomed EP3 Evaporimeter and Keeler's TearScope-Plus respectively. Significant improvement in LLT was noticed in the protection modality. The mean tear film evaporation rate doubled after exposure to the humidity of 5% to a value of 105.37 g/m/h (0.29 µl/min). All subjects displayed a significant reduction in non-invasive tear break-up time (NITBUT) with a mean NITBUT of 7.7 s after exposure to a desiccating environment for 15 min. A significant increase in NITBUT after the instillation of the drops was recorded in both methods. The results obtained from this study showed that a solution containing HP-Guar significantly improves tear film parameters under a desiccating environment. Apart from the tear evaporation rate, all tear parameters showed improvement after the use of HP-Guar eye drops. It is evident that tear film parameters respond differently to the management modalities and using CEC has the potential to provide researchers with a readily available method to evaluate the efficiency of tear supplementation.
本研究旨在评估羟丙基瓜尔胶（HP）配方（Systane）在干燥环境下通过保护和缓解治疗方式保护泪膜参数的疗效。研究对象在相对湿度（RH）为 5%和环境温度为 21°C的受控环境室（CEC）中暴露于不利的环境条件下，并使用 HIRCAL 网格、Servomed EP3 蒸发器和 Keeler 的 TearScope-Plus 分别测量泪膜破裂时间（TBUT）、泪膜蒸发率（TFER）和脂质层厚度（LLT）。在保护模式下，LLT 显著改善。暴露于 5%湿度后，平均泪膜蒸发率增加一倍，达到 105.37 g/m/h（0.29 µl/min）。所有研究对象在 15 分钟的干燥环境暴露后，非侵入性泪膜破裂时间（NITBUT）显著降低，平均 NITBUT 为 7.7 秒。两种方法均记录到滴注后 NITBUT 显著增加。本研究结果表明，含有 HP-瓜尔胶的溶液可显著改善干燥环境下的泪膜参数。除泪液蒸发率外，所有泪液参数在使用 HP-瓜尔胶滴眼液后均有所改善。显然，泪膜参数对管理方式的反应不同，使用 CEC 有可能为研究人员提供一种现成的方法来评估泪液补充的效率。
