A corneal ulcer

An open sore or epithelial defect with underlying inflammation of the cornea, the clear structure in the front of the eye. The cornea overlies the iris, which is the colored part of the eye, and is separated from the iris by the aqueous fluid in the anterior chamber of the eye.A corneal ulcer will often appear as a gray-to-white opaque or translucent area on the normally clear and transparent cornea. Some corneal ulcers may be too small to see without adequate magnification and illumination.

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