Dellen at Corneal Limbus (Photo)

This photo shows corneal thinning caused by a dellen (local dehydration of the cornea). Despite this “thinning” none of the cornea has been lost, it’s just dessicated.

These occur from excessive localized drying. In this case, a large spontanoues conjunctival hemorrhage has formed under the conjunctiva. The conjunctiva is epecially elevated right at the limbus at 4-oclock. Because of this “bump,” the cornea isn’t sufficiently covered with the eyelid during blinking.

Thus … dehydration and thinning.

The slitlamp beam is especially useful for determining corneal thickness … as you can see in this photo, the corneal stroma is very thin in this area.