A corneal abrasion (scratched cornea or scratched eye) is one of the most common eye injuries. A scratched cornea often causes significant discomfort, red eye and hypersensitivity to light. Corneal abrasions result from a disruption or loss of cells in the top layer of the cornea, called the corneal epithelium. The cornea is the clear front surface of the eye and part of its job is to focus light, enabling you to see. A healthy cornea is essential for good vision. In addition to disrupting vision, a scratched cornea makes your eye more susceptible to infection. So it’s important you see your eye doctor or visit an emergency room or urgent care center as soon as possible if you suspect you have a corneal abrasion.