Where it is
In the bony orbit, protected by the eyelids and moved by six extraocular muscles. Its wall has three layers: sclera and cornea outside, choroid, ciliary body and iris in the middle, retina inside.
What it does
The cornea and lens focus light, the iris controls how much enters through the pupil, and the retina converts light into nerve signals sent through the optic nerve (cranial nerve II).
Clinical relevance
- Unequal pupils (anisocoria) can be normal for some people, but a new difference is a neurologic warning sign.
- Chemical splash to the eye: irrigate immediately with large amounts of water or saline for at least 15 minutes.
- Penetrating objects should be stabilized, not removed.
Nursing focus
- For a client with visual impairment, introduce yourself, describe the room using clock positions and keep the environment consistent.