Corneal topography after ocular rubbing.

PURPOSE

To examine the immediate effect of ocular rubbing on corneal topography.

METHODS

Corneal topography and analysis were performed before, immediately after, and 5 minutes after eyelid rubbing in 29 volunteers without ocular disease.

RESULTS

The surface regularity index increased from a baseline of 0.24 to 0.91 ( p< 0.0001) immediately after rubbing and returned to baseline after 5 minutes. The surface asymmetry index increased from 0.27 to 0.89 ( p= 0.0018) immediately after rubbing. There was a small amount of astigmatism induced immediately by rubbing (0.5 diopter) ( p= 0.01).

CONCLUSIONS

Ocular rubbing should be avoided prior to standard corneal topography. The increased surface regularity index may reflect the alterations of the tear film and/or the molding of the corneal surface.