Cranial Nerves III, IV, VI Flashcards
nerves sometimes responsible for deviations of eye alignment
III, IV, VI
primary function of medial longitudinal fasciculus
coordinate eye movements
example of a lesion affecting the MLF
multiple sclerosis
the lobe that controls rapid or darting eye movement
frontal lobe
the lobe that controls smooth or following eye movement
occipital lobe
the result of uncoordinated attempts at controlling eye movements
nystagmus
disease of this nerve causes eyelid ptosis
CN III
disease of this nerve causes difficulty when looking down and in
CN IV
disease of this nerve causes inability to laterally deviate the eye on the same side
CN VI
disease of this nerve will diminish pupil constriction with bilateral symmetry
CN II
disease of this nerve will cause inability to constrict pupil in same eye
CN III
often due to lesions of the neck proximal to the carotid artery bifurcation
Horner’s syndrome
signs of Horner’s syndrome
ptosis, pupilloconstriction, facial anhydrosis, ipsilateral facial vasodilation
often due to lesions that are distal to the carotid artery bifurcation and that are along the internal carotid pathway
pupilloconstriction and ptosis
often due to lesions that are distal to the carotid artery bifurcation and that are along the external carotid pathway
vasodilation and anhydrosis
enophthalmos
inward sinking of the eyeball in the eye socket
3 components of accommodation
convergence, pupilloconstriction, lens thickening
the 3 components of accommodation are dependent on this CN
CN III
clinical findings that accompany nystagmus
nausea, vertigo, vomiting, ataxia
with nystagmus, which is the side with the problem?
the side that has the quick component
the 4 basic areas of the fundus of the eye that should be examined
optic disc, blood vessels, macula, general background