AIM To determine the characters of contrast sensitivity of dry eyes and influence of instillation of artificial tears, to discuss the possibility of application contrast sensitivity in the evaluation of tear film quality, and find out the theory for instill ion of artificial tears.

Methods The study comprised volunteers in whom dry eye had been diagnosed, and normal subjects which were diagnosed from 8-12, in 2007. Their SIT 、 BUT and Tear film interference pattern results were collected. All patients were given a contrast sensitivity testing at low 、 moderate、high spatial frequencies using the OPTEC 6500.BUT, SIT, Tear film interference pattern, low, moderate, and high score were collected. The analyzed the results with software of SPSS 12.0.

Results Classified the eyes by the diagnosis, which was made on the basis of the symptoms of dry eye, SIT, BUT and Tear film interference pattern. There were no significant differences in the mean ages of two groups. Contrast sensitivity score in the dry eye group at low, moderate and high frequencies higher than the control group. In the dry eye group, there was a statistically significant increase in contrast sensitivity scores at low, moderate and high frequencies after application of artificial tears (p<0.05).In the control group, although there was a significant increase in low 、moderate frequency scores after artificial tear application (p<0.05), there was not a significant change in dry eye group after application of artificial tears and the coutrol group.(p>0.05).
Conclusions The decreased contrast sensitivity in dry eyes improves with application of artificial tears. Therefore, the impeded quality of vision seen in dry eye patient could be restored closer to normal with artificial tear therapy. Beside, contrast sensitivity testing could be used in the follow –up of artificial tear therapy.