A foreign body is an object in your eye that shouldn’t be there, such as a speck of dust, wood chip, metal shaving, insect or piece of glass. The common places to find a foreign body are under the eyelid or on the surface of your eye.
Those most at risk are trades people such as labourers, woodcutters, fitters and turners, and boilermakers. Don’t try to remove a foreign body yourself. Go straight to your doctor or the nearest hospital emergency department for help.
Most injuries are minor and usually heal without further problems given the right care. Possible complications include:
Infection and scarring – if the foreign body is not removed from your eye, it may lead to infection and scarring. For example, metal objects react with the eye’s natural tears and rust forms around the metal. This is seen as a dark spot on the cornea (or clear window) of the eye and can cause a scar that may affect your vision. Once it is removed, symptoms should quickly ease.
Corneal scratches or abrasions – a foreign body may scratch the cornea, which is the clear membrane on the front of the eye. With the right care, most corneal abrasions – even large ones – heal within 48 hours. In some cases, however, they can lead to a long-term problem known as recurrent corneal erosion, which may occur even years after the original injury.
Ulcer – sometimes a scratch on the cornea doesn’t heal. A defect on the surface of your eye (ulcer) may form in its place. This could affect your vision or lead to an abscess.
Penetration of the eye – sometimes a projectile object can pierce the eye and enter the eyeball, causing serious injury and even blindness.
Corneal scarring – this can cause some degree of permanent visual impairment.
The doctor or nurse checks your vision.
Once they find the foreign body, they gently remove it after numbing the eye with anaesthetic eye drops. If it is central or deep, they will arrange for you to see an ophthalmologist (specialist eye doctor) to have it removed.
Your eye may be washed with saline (sterile salt water) to flush out any dust and dirt.
X-rays may be done to check whether an object has entered your eyeball.
Your eye is patched to allow it to rest and any scratches to heal.
You should not drive until the eye patch is removed and your vision has returned too normal.
Your doctor will want to see you again to check that your eye is healing and that your vision is all right.
You should not miss this appointment. Even though you may feel better, your eye may not have fully healed. The follow-up is needed to make sure the treatment is working.
If there are any serious problems, or a residual rust ring, you will be sent to an ophthalmologist.