Flashcards in Ocular-motor Disorders Deck (21):
Indicates weakness of a muscle
If eye is not focused on something, it drifts.
Indicates paralysis of the muscle.
Eye drifts even when focusing on a target
Eye is deviated inward
Eye is deviated outward
Eye is deviated upward
Eye is deviated downward
Which CN constricts the pupil? Sympathetic or parasympathetic?
Parasympathetic fibers of CN III. They supply the ciliary body and sphincter of iris.
Acquired CN III palsy
- Sudden onset of binocular horizontal, vertical or oblique diploplia.
- Ptosis or droopy eyelid.
Congenital CN III Palsy
- Found in young children
- May be able to suppress the second image in diploplia, may not complain.
- Ptosis and strabismus
- Amblyopia is major complication
Complete CN III palsy is usually associated with a large angle _____ and _____?
Exotropia and hypotropia. Down and out.
CN III palsy differential
- HTN, diabetes
CN III Palsy Tx
- Consult a neuroradiologist
- Tx is directed at underlying etiology
- Maximize function
Has longest intracranial course
Only nerve with a dorsal exit from the brainstem
Innervates Superior Oblique (SO4)
CN IV Palsy
- Binocular vertical diploplia/subjective tilting of objects
- Neck pain
What is nasal upshoot?
Ipsilateral Hypertropia. Eye is deviated upward .
CN IV Palsy causes greater hypertropia in _____ gaze.
CN IV Palsy Tx
LP if negative imaging
Treat underlying etiology
Enters orbit via the superior orbital fissure
Innervates Lateral rectus (LR6)
CN VI Palsy
- Binocular horizontal diploplia that worsens with gaze toward defective lateral rectus muscle.
- Strabismus toward paralyzed side.
CN VI Palsy Presentation
- Primary position esotropia
- Eye is turned in (crossed eye)