Intraocular Foreign Body
What is it?
This metal bit, released at high velocity by drilling, penetrated the sclera, bounced off the retina, and came to rest in the vitreous. It has caused vitreous hemorrhage that partially obscures it.
High speed fragmentsmetal bits from drilling or hammering, shotgun or BB pelletsstrike the eye so quickly that the patient may barely notice that something has happened until vision becomess blurred.
Intraocular foreign bodies may lodge within the eye or exit through a posterior hole ("double perforation") and come to rest in the orbit. Corneal entry wounds are usually obvious because they tear and opacify the cornea. Eyelid and scleral entry holes are usually too small to see without magnified examination.
If the missile penetrates the lens, the lens will rapidly opacify. Vitreous bleeding may quickly eliminate the red reflex in the pupil and conceal the fundus from view.
What to do?
The mere history of sudden eye pain after exposure to metal-on-metal drilling or shotgun/BB pellets should suggest an intraocular foreign body. The entry wound may be too small to lower intraocular pressure or deform the globe. Despite a negative examination, put a shield over the orbit and call an ophthalmologist.
Intraocular foreign bodies are removed urgently when this can be done without creating too much damage because they may be infected, leach toxic chemicals, and attract a fibrous cocoon that degrades vision. Those that lodge in the anterior chamber can often be lifted out surgically.