Before the Ophthalmologist removes the corneal foreign body, the vision has to be measured to make sure that there is no visual disturbance and the eye gently examined at the slit lamp with the help of some fluorescein drops to show whether there are any scratches. Occasionally, the corneal foreign body is in fact embedded in the upper eyelid on the tarsal conjunctiva, which is the undersurface of the top lid and is causing tell-tale scratches across the upper part of the front of the eye of the cornea. If those tell-tale scratches are seen with the fluorescein eyedrop and using the blue light, the ophthalmic specialist will then evert the upper lid and see if there is a conjunctival foreign body called a sub-tarsal conjunctival foreign body stuck beneath and then remove that either with a cotton bud or a fine needle.
Once the corneal foreign body is removed safely, it is customary to check the rest of the eye and make sure that no other foreign bodies have been missed and that there are no penetrating foreign bodies. The patient will then be either padded over with an eye pad for 24 hours and told to start antibiotic drops the day after, or not padded and told to start antibiotic drops the very same day. There is also a risk of infection with a corneal foreign body. Therefore four to five days of antibiotic drops are indicated afterwards. Drops are most commonly used during the day, but ointment can be employed instead, and patients could use the cream at night.
Corneal foreign bodies can be exquisitely painful and are subtle. They often cannot be seen by the naked eye by the patient or another observer and require an ophthalmic specialist with specialised equipment called the slit lamp, which magnifies the surface of the eye to visualise and remove the corneal foreign body. Sometimes the foreign body or object feels as though it is on the cornea at the front of the eye, but in fact is stuck underneath the eyelid and then the upper eyelid has to be everted, and conjunctival foreign body gently brushed off. Usually, recovery from a corneal foreign body or object or subconjunctival foreign body is very rapid within 24 hours. However, if the ophthalmologist has recommended you have the antibiotic drops for a few more days even though it may feel normal, those instructions are best followed to prevent infection.
Occasionally the corneal foreign body leaves a small coloured superficial rust ring that can cause irritation unless also removed. Therefore it is common that the Ophthalmologist will want to review the eye after a few days to make sure that the cornea has fully healed and that there is no residual rust ring.