Eye movement disorders - classifications Flashcards Preview

Ocular Disease 3 - Final > Eye movement disorders - classifications > Flashcards

Flashcards in Eye movement disorders - classifications Deck (35)
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1

what are the 4 general categories of eye movement disorders?

binocular diplopia, diplopia sub-type INO, gaze palsy, and nystagmus

2

what is binocular diplopia?

patient see double with both eyes open - goes away when they close one eye (eyes are out of alignment)

3

what is diplopia sub-type INO?

internuclear ophthalmoplegia = specific type of EOM anomaly that may or may not have diplopia in some positions

4

what is a gaze palsy?

fusion is usually present but the eyes cannot move into certain positions of gaze

5

what is nystagmus?

specific type of unsteady fixation characterized by slow movement in one direction and a fast movement in other direction

6

what are the 3 main layers/levels that control eye movements?

supranuclear level, premotor level, and the final common pathway

7

what is the supranuclear level for controlling eye movements?

structures in the cortex for saccades, pursuits, OKN, and VOR (cortical and subcortical) and control pre-motor nuclei

8

what is the pre-motor level for controlling eye movements?

organize eye movements by coordinating the nuclei that control the muscles = riMLF, PPRF, vestibular nuclei

9

what is the final common pathway for controlling eye movements?

the cranial nerves that control movements = CN3, CN4, CN6

10

what are 3 locations that pathology can occur for EOM functions?

in a muscle, in the synapse between a nerve ending and the muscle, and in the orbit

11

what are 3 locations that pathology can occur for a nerve that controls EOMs?

in the brainstem nucleus (midbrain or pons), interstitial compartment in the brainstem, and in the space where the axons exit the brain

12

what are the 4 locations of pathology for the pre-motor structures that control EOM location?

PPRF (horizontal), riMLF (vertical), vestibular nuclei (CN8), MLF (internuclear)

13

what are the 4 locations of pathology for the structures that control and maintain fixation?

semicircular canals, CN8, vestibular nuclei, and cerebellum (especially the flocculonodular lobes)

14

what are the 3 locations of pathology for the higher order supranuclear structures?

superior colliculus, frontal eye fields (frontal lobe - saccades), occipital eye fields (pursuits)

15

what is the general symptom/sign for pathology in the orbit, EOM, or synapse?

diplopia

16

what is the general symptom/sign for pathology in the nucleus or nerve?

diplopia

17

what is the general symptom/sign for pathology in the pre-motor structures?

INO

18

what is the general symptom/sign for pathology in the supranuclear structures?

gaze palsy

19

what is the general symptom/sign for pathology in the vestibular system and CN8?

nystagmus

20

what structures are present in the orbit?

EOMs, nerves, fascia, connective tissue

21

what structures are present in the orbital apex?

superior orbital fissure and optic canal

22

what structures are present in the nerve?

subarachnoid space, circle of willis, cavernous sinus, superior orbital fissure and posterior orbit

23

what structures are present in the nerve nucleus and interstitial axons (midbrain)?

descending pyramidal system rostral to the decussation and red nucleus (motor system)

24

what structures are present in the nerve nucleus and interstitial axon (pons)?

descending pyramidal system rostral to the decussation, vestibular nuclei, and cerebellum is nearby

25

what structures are present in the pre-motor (brainstem)?

MLF, SC, vestibular system, and cerebellum

26

what structures are present in the pre-motor (supranuclear)?

frontal and occipital lobes

27

what structures are present in the vestibular system and CN8?

facial nerve, auditory system, descending pyramidal system rostral to decussation

28

what are the associated signs and symptoms for the orbit?

space-occupying lesion and CN5

29

what are the associated signs and symptoms for the orbital apex?

space-occupying lesion and CN2

30

what are the associated signs and symptoms for the nerve?

aneurysm, space-occupying lesion and inflammation