In the immediate post-operative period the bond between the newly created flap and the underlying corneal stroma is weak, and the epithelium has just been subjected to the pharmacologic and mechanical stresses noted above. It is imperative that the surface continuity of the epithelium between the edge of the flap and the surrounding surface be restored as rapidly as possible, as reestablishment of an intact epithelial surface minimizes the risks of flap shift, epithelial ingrowth, and infection. For all these reasons, it is a generally accepted standard of care to use aggressive ocular lubrication during the post-operative period in order to maximize the speed of epithelial recovery.