Himebaugh Nikole L, Begley Carolyn G, Bradley Arthur, Wilkinson Jenni A
Indiana University School of Optometry, Bloomington, Indiana 47405, USA.
Optom Vis Sci. 2009 Feb;86(2):E106-14. doi: 10.1097/OPX.0b013e318194e962.
This study investigates the relationship between blinking, tear film break-up, and ocular symptoms for normal and dry eye subjects performing four different visual tasks.
Sixteen control and sixteen dry eye subjects performed four visual tasks (looking straight ahead, watching a movie, identifying rapidly changing letters, and playing a computer game) while blink patterns and fluorescein images of the tear film were videotaped. Pre and posttesting symptom questionnaires, querying the intensity of nine symptoms of ocular irritation, were completed by all subjects. Blink rate and blink amplitude were computed from digitized videos. The percentage of tear film break-up before the blink was calculated.
Dry eye subjects had a significantly higher blink rate (p = 0.017, t-test). Both groups blinked significantly less during the game and letter tasks (p < 0.04, t-test). Partial blinks were common as were clusters or "flurries" of rapid blinks, but there was no significant difference in blink amplitude for control and dry eye subjects. Tear film break-up in normal subjects was typically inferior; whereas dry eye subjects showed more tear break-up centrally and superiorly. Real-time video recording of tear break-up and blink behavior pointed to complex interaction between the two. Dry eye subjects shifted more toward intense ocular symptoms at posttesting (p < 0.05, Wilcoxon signed rank) than controls. Both groups showed a shift toward more corneal staining at posttesting (p < 0.05, Wilcoxon signed rank), which was typically inferior.
Reduced and incomplete blinking along with increased tear film break-up during normal visual tasks may explain the increased level of ocular discomfort symptoms reported at the end of the day, particularly in dry eye patients.
本研究调查正常受试者和干眼受试者在执行四项不同视觉任务时眨眼、泪膜破裂与眼部症状之间的关系。
16名对照受试者和16名干眼受试者执行四项视觉任务（直视前方、观看电影、识别快速变化的字母以及玩电脑游戏），同时拍摄眨眼模式和泪膜的荧光素图像。所有受试者均完成测试前和测试后的症状问卷，询问九种眼部刺激症状的强度。从数字化视频中计算眨眼频率和眨眼幅度。计算眨眼前泪膜破裂的百分比。
干眼受试者的眨眼频率显著更高（p = 0.017，t检验）。两组在玩游戏和字母识别任务期间眨眼均显著减少（p < 0.04，t检验）。不完全眨眼很常见，快速眨眼的簇状或“阵发”也很常见，但对照受试者和干眼受试者的眨眼幅度没有显著差异。正常受试者的泪膜破裂通常较差；而干眼受试者在中央和上方显示出更多的泪膜破裂。泪膜破裂和眨眼行为的实时视频记录表明两者之间存在复杂的相互作用。与对照受试者相比，干眼受试者在测试后更倾向于出现强烈的眼部症状（p < 0.05，Wilcoxon符号秩检验）。两组在测试后均显示角膜染色增加（p < 0.05，Wilcoxon符号秩检验），染色通常在下方。
在正常视觉任务期间眨眼减少且不完全以及泪膜破裂增加，可能解释了在一天结束时报告的眼部不适症状水平增加的原因，特别是在干眼患者中。
