Tao Aizhu, Cai Chunyan, Shen Meixiao, Wang Jianhua, Chen Zhao, Xu Suzhong, Li Ming, Lu Fan
School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang, China.
Optom Vis Sci. 2011 Dec;88(12):1433-8. doi: 10.1097/OPX.0b013e3182303631.
To determine the effect of overnight wear of contact lenses (CL) on tear meniscus, tear film stability, and subjective comfort.
Sixty asymptomatic subjects were divided into three groups. The control group was composed of 20 non-CL wearers. Twenty inexperienced and 20 experienced CL wearers were enrolled as group 1 and group 2. For each subject in groups 1 and 2, a hydrogel and a silicone hydrogel CL were randomly assigned to each eye. Optical coherence tomography was used to determine volumes of the upper and lower tear menisci. Tear film stability was determined by non-invasive tear break-up time (NITBUT) measured by tearscope. A previously used questionnaire assessed dry eye symptoms. Subjects were evaluated during an 11-h period, including immediately before and after sleeping.
Compared with the presleep levels, tear meniscus volume in the control group increased immediately after awakening and recovered by 1 hour later (p < 0.05). In contrast, tear meniscus volume in lens wearers increased on eye opening and recovered by 10 min later (p < 0.05). Tear meniscus volumes in CL wearers were less than those in controls at eye opening. NITBUT and comfort scores decreased immediately after CL insertion (p = 0.00). After eye opening, NITBUT was larger than the presleep levels until 10 min later. The comfort score was lower than the presleep values until 5 min later.
Dynamic changes in the tear menisci, NITBUT, and comfort level were evident in both inexperienced and experienced CL wearers during and after overnight wear. Decreased tear meniscus volumes and tear film stability may contribute to lower eye comfort for extended CL wearers. The tearing on eye opening may facilitate improvement of ocular comfort and tear refreshment for a reconditioning of the tear system and the CL.
确定隐形眼镜过夜佩戴对泪液半月皱襞、泪膜稳定性和主观舒适度的影响。
60名无症状受试者分为三组。对照组由20名不佩戴隐形眼镜者组成。20名无经验的隐形眼镜佩戴者和20名有经验的隐形眼镜佩戴者分别作为第1组和第2组。对于第1组和第2组的每位受试者，每只眼睛随机分配一副水凝胶隐形眼镜和一副硅水凝胶隐形眼镜。使用光学相干断层扫描来确定上下泪液半月皱襞的体积。通过泪液镜测量的非侵入性泪膜破裂时间（NITBUT）来确定泪膜稳定性。使用先前使用的问卷评估干眼症状。在11小时期间对受试者进行评估，包括睡觉前后即刻。
与睡前水平相比，对照组泪液半月皱襞体积在醒来后即刻增加，并在1小时后恢复（p<0.05）。相比之下，佩戴隐形眼镜者的泪液半月皱襞体积在睁眼时增加，并在10分钟后恢复（p<0.05）。佩戴隐形眼镜者在睁眼时的泪液半月皱襞体积小于对照组。插入隐形眼镜后NITBUT和舒适度评分即刻下降（p = 0.00）。睁眼后，NITBUT在10分钟前大于睡前水平。舒适度评分在5分钟前低于睡前值。
过夜佩戴期间及之后，无经验和有经验的隐形眼镜佩戴者的泪液半月皱襞、NITBUT和舒适度水平均出现明显的动态变化。泪液半月皱襞体积减小和泪膜稳定性降低可能导致长时间佩戴隐形眼镜者的眼部舒适度降低。睁眼时的流泪可能有助于改善眼部舒适度和泪液更新，以修复泪液系统和隐形眼镜。
