The cornea is the clear front window of the eye. It transmits light to the interior of the eye allowing us to see clearly. Corneal injury, disease, or hereditary conditions can cause clouding, distortion, and scarring. Corneal clouding, much like frost on a glass windowpane, blocks the clear passage of light to the back of the eye, reducing sight sometimes even to the point of blindness. In addition, corneal injury and disease can be painful, sometimes the most intense pain we can experience.

While not as common as corneal disease, cornea injuries can be quite serious. Knives, pencils, and other sharp objects can cause severe injury to the cornea. Fireworks, exploding batteries, and toxic chemicals, especially alkalis, can also result in severe scarring of the cornea. In fact, protection of the cornea is the reason emergency washing of the eye is absolutely necessary when the eye is exposed to toxic chemicals. Most corneal injuries are preventable with protective glasses and proper precautions when dealing with hazardous substances.