The importance of the precorneal tear film for the quality of optical imaging

Abstract

The optical function of the eye critically depends on the presence of an intact pre-corneal tear film. Abnormalities of the tear film such as those occurring in the dry eye syndrome or in otherwise irritated eyes may interfere with vision. In 30 patients with dry eyes artificial tears were found to produce stastistically significant improvement of vision (p<0·001) while no significant changes were seen in the untreated partner eyes. Static perimetry in another 30 patients using the 'macular programme' of the automatic Humphrey 620 perimeter showed artificial tears to increase mean thresholds significantly (p<0·001) whereas no significant differences were seen in the untreated partner eyes.