When the cornea swells it may lose its clarity or cause blisters to appear on its surface, or both. The causes of corneal swelling include:

  • Corneal dystrophies (Fuch’s dystrophy)
  • Injury
  • Surgical damage (cataract surgery, other intra-ocular surgery)
  • Sudden increase in intra-ocular pressure (acute glaucoma)

Some corneal edema can be treated medically. If the eye pressure is high, it can be lowered. Edema resulting from surgical damage may improve over time. If the swelling is limited to the surface epithelium, concentrated NaCl (salt) eye drops are used to osmotically remove fluid out of the cornea and improve the vision.

A corneal transplant is needed if the swelling can not be treated adequately with eye drops and there is significant visual loss from the swelling.