Innervations Flashcards
CN I fiber type
SVA (special visceral afferent)
CN II fiber type
SSA Special somatic afferent fibers
Lesion to the right visual cortex (before the crossing of chiasm)
Right side total blindness
Unilateral inopsia right side
Right side blindness
Lesion to the optic chiasm
Bilateral hemianopsia (loss of peripheral vision)
Lesion to right side of optic tracts (after optic chiasm)
homonymous hemianopsia (loss of vision on left side of eyes)
What optic nerve fibers cross?
What optic nerve fibers don’t cross?
Nasal fibers cross in the optic chiasm (peripheral vision)
Temporal fibers do not cross (central vision)
Why is thinking about the optic vision fields so confusing?
Bc visual fields are seen contralaterally. Right visual field is seen by the left visual cortex. Left visual field of that eye is seen by the right visual cortex.
Nasal fibers see the peripheral vision (later cross)
Temporal fibers see your central vision (never crosses)
What 3 cranial nerves move your eye around?
CN III, CN IV, and CN VI
Remember LR6SO4
Extraoccular conjugate movement means?
eyes move at equal rate and same direction
Strabismus means ?
Cross-eyed
(lateral rectus muscle)
CN ?
Ptosis and/or Blephratosis mean what ?
Drooping eyelid
(levator palpebra superioris)
CN ?
What 5 motor muscles does CN III innervate?
AND
with what type of fibers does it do this with?
Levator palperal superioris
Superioris rectus
Medial rectus
Inferior rectus
Inferior oblique
SVE= special visceral efferent
Cranial nerve to skeletal muscle
What two parasympathetic functions/muscles does CN III control.
AND
with what type of fibers?
GVE- General visceral efferent
fibers from the cranium to autonomic system
Cilliary muscles
Sphincter pupillare muscle.
What is the only CN that emerges dorasally?
Also the only CN that crosses inside the cranium
CN 4 Trochlear nerve
