配戴角膜接触镜加重注视VDT对泪膜功能损害

The impact of contact lens wear on tear film function of visual display terminal workers

目的研究长时间注视视频终端（VDT）并且配戴角膜接触镜（CL）对泪膜功能的影响。方法前瞻性病例对照研究。将研究对象分为三组：A组56例（112只眼），每日注视VDT〉5h且配戴cL≥1年；B组45例（90只眼），每日注视VDT〉5h，未配戴CL；C组39例（78只眼），每日注视VDT〈2h，配戴CL≥1年。观察三组人群SchirmerI试验（Sit），泪膜破裂时间（BUT），角膜荧光素（FL）染色，比较三组之间差异是否有统计学意义。结果A组、B组、c组的BUT分别为（6．2±2．9）s、（7．2±4．0）s、（8．0±4．3）s，三组间差异有统计学意义（P=0．005），两两比较中，A组和B组，A组和C组之间差异有统计学意义，B组和c组之间差异无统计学意义。Sit和FL染色结果差异无统计学意义。结论长时间注视VDT会损害泪膜功能，配戴cL加重注视VDT对泪膜功能的损害。

Objective To study the effects of contact lens wear on tear film function of visual display terminal （VDT） workers. Methods In this prospective casecontrol trial, a total of 140 pa tients （280 myopic eyes） were divided into three groups： group A （56 cases ） that were engaged in VDT work no less than 5 hours a day and had wore contact lenses at least one year, group B （45 cases） that were engaged in VDT work no less than 5 hours a day and had never wore contact lens es, and group C （39 cases ） that were engaged in VDT work less than 2 hours a day and had wore contact lenses at least 1 year. Schimer I test （Sit）, tear break up time （BUT） and fluorescein （FL） stain were measured among three groups. Results The BUT value was 6.22.9s in group 1, 7.2±4.0s in group 2, 8.0±4.3s in group 3 （P =0.005）. The BUT value in group A was significantly lower than that in group B and group C, there were no significant differences between group B and group C. There were no significant differences in Sit and FL stain among three groups. Conclu sions Longterm VDT work impairs the function of tear film. People who wear contact lenses suffer more changes on tear film function than those who never wear contact lenses when they are en gaged in longterm VDT work.