Hirota Masakazu, Uozato Hiroshi, Kawamorita Takushi, Shibata Yuko, Yamamoto Shinya
Department of Visual Science, Kitasato University Graduate School of Medical Sciences, Kitasato, Kanagawa, Japan.
Optom Vis Sci. 2013 Jul;90(7):650-7. doi: 10.1097/OPX.0b013e31829962ec.
The purpose of this study is to assess changes in tear film stability caused by incomplete blinking.
Eleven subjects (mean age, 21.3 years) participated in this study. All subjects had a visual acuity of 20/20 or better and normal ocular health. The subjects were asked to play a game for 60 min on a personal computer as part of a visual display terminal (VDT) experiment. Each subject's blinking was observed by a Web camera that was attached to the top of the display. Every 15 min, the VDT experiment was interrupted for measurement. An RT-7000 (Tomey Co., Ltd., Nagoya, Japan) was used to measure ring breakup time as a parameter of tear film stability. An OPD-Scan II ARK-10000 (NIDEK Co., Ltd., Aichi, Japan) was used to measure corneal aberrations.
Although the total blink rate changed very little, the complete and incomplete blink rates fluctuated during the VDT experiment. Both types were plotted along symmetrical cubic approximation curves. Noninvasive (ring) breakup time at 30 min (4.33 ± 2.57 s) was significantly shorter (p < 0.01) than that at baseline before the VDT experiment (8.62 ± 1.54 s). After 30 min, the incomplete blink rate began decreasing (fewer incomplete blinks), whereas the complete blink rate began increasing. Ring breakup time increased (improved) after 45 min; however, the incomplete blink rate began to increase again after approximately 50 min.
Even if the total blink rate decreases, the tear film remains stable so long as almost all blinks are complete. The incomplete blinking contributes to tear film instability and is variable with prolonged VDT exposure. Our study indicated that the tear film stability was determined by blinking quality, and the predominance of blinking type relates to tear film stability.
本研究旨在评估不完全眨眼引起的泪膜稳定性变化。
11名受试者（平均年龄21.3岁）参与了本研究。所有受试者视力均为20/20或更好，眼部健康正常。作为视觉显示终端（VDT）实验的一部分，受试者被要求在个人电脑上玩60分钟游戏。通过连接在显示器顶部的网络摄像头观察每个受试者的眨眼情况。每15分钟，中断VDT实验进行测量。使用RT - 7000（日本名古屋多美公司）测量泪膜破裂时间作为泪膜稳定性参数。使用OPD - Scan II ARK - 10000（日本爱知县尼德克公司）测量角膜像差。
尽管总眨眼率变化很小，但在VDT实验期间，完全眨眼率和不完全眨眼率有所波动。两种类型均沿对称三次近似曲线绘制。30分钟时的无创（环形）破裂时间（4.33±2.57秒）明显短于VDT实验前基线时的时间（8.62±1.54秒）（p<0.01）。30分钟后，不完全眨眼率开始下降（不完全眨眼次数减少），而完全眨眼率开始上升。45分钟后环形破裂时间增加（改善）；然而，不完全眨眼率在大约50分钟后又开始增加。
即使总眨眼率下降，只要几乎所有眨眼都是完全的，泪膜仍保持稳定。不完全眨眼会导致泪膜不稳定，并且随着VDT暴露时间延长而变化。我们的研究表明，泪膜稳定性由眨眼质量决定，眨眼类型的优势与泪膜稳定性有关。
