Cornea is the protective membrane covering on eyeball, which should be transparent and clear with full of nerve ends. Because it is full of nerve ends, it is extremely sensitive that if any dust or sand got into eyes or beneath eyelids would make you feel very uncomfortable. Corneal abrasion will cause pain, foreign body sensation, sensitivity to light, excessive tear and squinting. Normally mild abrasion can heal up without any treatment in about 3 days. As to serious case, it take longer to heal up. Because there is no blood vessels on cornea, so any wound on it heals very slow. If anything gets into eyes which caused corneal abrasion, don't rub your eyes but flushing eyes with water. To treat corneal abrasion, you can apply some antibiotics eye drops or ointment to prevent infection and lubricate eyes. Some medication might be prescribed to relieve pain. Don't wear contact lenses until you are completely healed up, because wearing contact lenses might make your abrasion worse. Wear sunglasses while going outside could help reduce the pain from strong light.
