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• Corneal Disorders
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The cornea is the domed, transparent covering in the front of the eye that protects the iris and lens and helps focus light on the retina. It is composed of cells, protein, and fluid. The cornea looks fragile but is almost as stiff as a fingernail. However, it is very sensitive to touch.

Corneal disease or damage can cause pain, tearing, and loss of vision. A slit lamp, which shows the cornea with magnification, is usually used to examine the cornea (see Diagnosis of Eye Disorders: Slit-Lamp Examination). A doctor may apply eye drops that contain a dye called fluorescein, which temporarily stains areas of the cornea where cells are damaged, making these areas easier to identify.

Last full review/revision October 2008 by Melvin I. Roat, MD. FACS