Word parts
What it means
The oculomotor nerve (cranial nerve III) controls most of the muscles that move the eye, the muscle that lifts the upper eyelid, and the muscle that makes the pupil smaller. When it is damaged or squeezed, the eye may turn down and out, the eyelid may droop and the pupil may be large and slow to react.
For the nurse
Pupil checks are part of every neuro check. In a client with a head injury or brain swelling, a pupil that becomes newly large or sluggish can mean pressure on this nerve: report it at once.
Related terms
intracranial pressure
The pressure inside the skull, made by the brain, the blood and the fluid around the brain.
-ptosis
A word ending that means drooping, sagging or falling down of an organ or part.
craniotomy
Surgery in which a piece of the skull is removed to reach the brain, and usually put back at the end.