One may see rainbows around headlights or streetlights. When severe, corneal edema can substantially blur the vision. This usually affects both eyes. Prior eye surgery, such as cataract surgery, can lead to temporary corneal edema. If the cornea was not healthy prior to surgery, an intraocular procedure can cause the cornea to fail, and severe edema can result.
Eye trauma can cause corneal damage and edema.
Acute glaucoma, with very high eye pressure, can cause corneal edema as well as pain. Contact lens overuse can lead to corneal edema, and is a risk factor for infection. Treatment of corneal edema sometimes depends on its cause. This draws fluid out of the cornea and into the tears, and helps to clear the cornea. Sometimes a corneal transplant is combined with cataract extraction, a lens implant exchange, or removal of vitreous material, if these are also problems.