The effect of tear substitute and silicone oil on re-epithelisation of the cornea.

PURPOSE

An animal model study was conducted to compare the effects of recurrent applications of an artificial cellulosic tear substitute and silicone oil on corneal reepithelisation.

METHODS

A controlled wound was inflicted to the corneas of two groups of rabbits; one group was treated with tear substitute (5 eyes), while the other group received silicone oil (5 eyes). The left eye served as the control in both groups (10 eyes). The rate of re-epithelisation was measured at intervals of 6 h until complete wound closure was observed. After complete wound closure, the rabbits were killed and histological examinations were performed.

RESULTS

The wounds of eyes treated with tear substitute closed at a statistically significant faster rate (at 24, 44, 80 h; p < 0.05) than those treated with silicone oil or the untreated eyes. At 48 h after re-epithelisation, the eyes treated with tear substitute presented a normal epithelium while the untreated and silicone-treated eyes presented an abnormally structured epithelium.

CONCLUSION

This study demonstrates a favourable effect of tear substitute on corneal re-epithelisation in an animal model, in terms of both rate of re-epithelisation and histological aspects of the new epithelium.