Section 20. Eye Disorders

Chapter 227. Eye Injuries

Topics: Introduction | Blunt Injuries | Foreign Objects | Burns

Foreign Objects

The most common eye injuries are those to the cornea and outer surface of the eye (conjunctiva) caused by foreign objects. Although most of these injuries are minor, some--such as penetration of the cornea or development of an infection from a cut or scratch on the cornea--can be serious.

Perhaps the most common source of surface injuries is contact lenses. Poorly fitting lenses, lenses left in the eyes too long, lenses left in inappropriately during sleep, inadequately sterilized lenses, and forceful or inept removal of lenses can scratch the surface of the eye.

Other causes of surface injuries include glass particles, wind-borne particles, tree branches, and falling debris. People with certain occupations or hobbies are particularly likely to have small particles fly in their faces. For example, hammering a nail or other metal object with a steel hammer produces white-hot particles of steel that resemble sparks. Any of these white-hot particles can enter the unprotected eye and embed themselves deep within it. Protective eyewear (safety glasses) can help prevent injuries.

Symptoms

Injury to the surface of the eye usually causes pain and a feeling that there is something in the eye. It may also produce an increased sensitivity to light, redness, bleeding from blood vessels on the surface of the eye, or swelling of the eye and eyelid. Vision may become blurred.

Foreign bodies that penetrate the inside of the eye or injuries that are contaminated with soil or vegetable matter (for example, an injury caused by a tree branch) are particularly likely to become infected. Prompt diagnosis and appropriate treatment can help prevent infection.

Diagnosis and Treatment

Diagnosis of eye injury is based on the person's symptoms and the circumstances of the injury. Examination of the eye is carried out simultaneously with the procedure to remove the foreign object. Sometimes, additional tests, such as computed tomography (CT), may be needed.

Eye drops containing a dye that glows under special lighting make the object more visible and reveal surface abrasions. The surface of the eye is usually numbed with anesthetic drops. Using a special lighting and magnifying instrument, such as a binocular lens or slit lamp, to view the surface of the eye in detail, the doctor then removes the foreign object. Often the foreign object can be lifted out with a moist sterile cotton swab or flushed out with sterile water. Foreign objects that cannot be dislodged easily can often be removed painlessly with a needle or a special instrument. When metal foreign bodies are removed, they can leave a ring of rust, which may need to be removed with a special burr (a small surgical tool with a tiny, rotating, grinding and drilling surface).

An antibiotic ointment is usually applied for several days. Large abrasions of the cornea may require additional treatment: The pupil is kept dilated with eye drops, and an antibiotic ointment is applied; a patch may be placed over the eye to keep it closed. An abrasion that results from a contact lens or an object that may be contaminated with soil or vegetation is not patched, because patching can worsen the risk of a serious infection of the cornea (corneal ulcer). Fortunately, the surface cells of the eye regenerate rapidly. Even large abrasions tend to heal in 1 to 3 days. Follow-up examination by an ophthalmologist 1 or 2 days after injury is wise. Corneal abrasions are uncomfortable, so drugs to relieve pain are often given by mouth.

When a foreign object has pierced the deeper layers of the eye, an ophthalmologist should be consulted immediately for emergency surgical treatment to remove the object. Prompt removal reduces the risk of infection.