Conjunctival epithelium in healing of corneal epithelial wounds

The mitotic rate and goblet cell content of conjunctival epithelium following total or central corneal epithelial removal using n-heptanol was measured to determine how the conjunctival epithelium responds to injury and whether conjuctiva responds to central corneal epithelial loss. One day following a wound that removed corneal, limbal, and 1-2 mm of bulbar conjunctival epithelium, the mitotic rate of the remaining conjunctival epithelium was ten times normal (P less than 0.001), proving that the conjunctiva responds to injury by cellular proliferation. At 1 and 2 days following a limited 10 mm diameter central corneal wound, the mitotic rate of peri-limbal conjunctival epithelium was three to four times normal (P less than 0.01), and even following a 5 mm diameter central wound, it was three to four times normal on day 1 (P less than 0.05). Goblet cell frequency was a less reliable indicator of conjunctival response to corneal injury: it was decreased following the largest and smallest wounds but not affected by the 10 mm diameter wound. These studies demonstrate that conjunctival epithelium peripheral to the cornea is affected by small central corneal wounds, and may therefore play a role in corneal epithelium healing.