CN III: Oculomotor Nerve Flashcards
1
Q
Path
A
Interpeduncular fossa –> Superior orbital foramen
2
Q
Motor functions
A
- medial rectus (rotates eye in)
- superior rectus (rotates eye up)
- inferior rectus (rotates eye down)
- inferior oblique (rotates eye diagonally and up)
- levator palpebrae superioris (opens eyelid)
3
Q
Parasympathetic functions
A
- constrictor pupillae/pupillary sphincter (causes pupil to constrict)
- ciliary muscle (lens thickens; distance accommodation)
4
Q
How to test?
A
cardinal eye movement
5
Q
Pathology/disorders?
A
- bilateral external strabismus (wall-eyed)
- ptosis (sagging eyelid)
- pupils dilated
6
Q
Upper division of CN III
A
- levator palpibrae superioris
- superior rectus
7
Q
Lower division of CN III
A
- medial rectus
- inferior rectus
- inferior oblique
8
Q
CN III is one of FOUR cranial nerves that carry parasympathetic functions. What are the other three?
A
- Facial (CN VII)
- Glossopharyngeal (CN IX)
- Vagus (CN X)
9
Q
CN III is one of THREE cranial nerves that helps with conjugal deviation. What are the other two?
A
- Trochlear (CN IV)
- Abducens (CN VI)
10
Q
What could result on the contralateral side of a subdural hematoma?
A
uncal herniation
11
Q
What could an uncal herniation cause?
A
pinching of the CN III nerve
