Recurrent corneal erosion
Recurrent corneal erosion (RCE) is a disorder of the eyes characterized by the failure of the cornea's outermost layer of epithelial cells to attach to the underlying basement membrane (Bowman's layer). The condition is excruciatingly painful because the loss of these cells results in the exposure of sensitive corneal nerves.
Source: Wikipedia — Recurrent corneal erosion (CC BY-SA 4.0)