Foreign bodies that penetrate the eyeball are rare but can lead to a serious infection and complications, including a risk of developing blindness.
(See also Overview of Eye Injuries.)
Causes of Intraocular Foreign Bodies
Explosions and any tool with a metal-on-metal mechanism can cause intraocular foreign bodies by causing small particles to fly in a person’s face. For example, using high-speed machines (such as drills and saws) or hammering a nail or other metal object with a hammer can produce high-speed metallic particles. Any of these particles can enter the unprotected eye and become embedded deep within it. Similarly, if a person is accidentally poked in the eye with a pencil, a small piece of the tip could break off and become embedded in the eye.
Foreign bodies that penetrate the inside of the eye can damage the structures within the eyeball and lead to an infection inside of the eye (endophthalmitis).
Symptoms of Intraocular Foreign Bodies
During the first hours after injury, symptoms of intraocular foreign bodies may be similar to those of corneal abrasions and corneal foreign bodies. However, people with intraocular foreign bodies may also have a noticeable loss of vision. Fluid may leak from the eye, but if the foreign body is small, the leak may be so small that the person is not aware of it.
Diagnosis of Intraocular Foreign Bodies
An ophthalmologist's evaluation
Computed tomography (CT)
slit lamp. The dye and slit lamp make visible any small leaks of fluid from the eye as well as puncture marks.
Any foreign bodies outside of the eyeball are removed. If an intraocular foreign body is suspected after the examination, a plain x-ray is sometimes taken. However, a CT is usually done. Magnetic resonance imaging (MRI) is sometimes needed to confirm the presence of an object or clarify its nature. An MRI is not done first because it may cause any metallic objects trapped in the eye to move in the magnetic field of the MRI.
Treatment of Intraocular Foreign Bodies
Antibiotics
Removal of the foreign object, usually with surgery
tetanus vaccine is given as soon as possible.
If necessary, pain and vomiting can be controlled with medications.
As soon as possible, a protective shield (such as a commercially prepared shield or the bottom part of a paper cup) is taped over the eye to avoid unintentional pressure that could further damage the eye. The injured eye should never be patched.
An ophthalmologist should remove the foreign body as soon as possible. Prompt removal reduces the risk of infection. Usually a surgical procedure is needed to remove the foreign body.
Prevention of Intraocular Foreign Bodies
People involved in activities or work using grinders, drills, saws, or hammers, should wear protective eyewear (such as face shields, safety glasses, or goggles) to help prevent intraocular foreign bodies and other eye injuries.
