Eye Movements Flashcards
(100 cards)
1
Q
This extraocular muscle rotates the eye medially (intorsion) and contributes to depression
A
Superior oblique
2
Q
This extraocular muscle rotates the eye laterally (extortion) and contributes to elevation
A
Inerior oblique
3
Q
Is superior oblique muscle involved in intorsion or extortion of the eye?
A
Intorsion (towards nose)
4
Q
Is inferior oblique muscle involved in intorsion or extortion of the eye?
A
Extortion (away from nose)
5
Q
This nerve supplies the superior oblique muscle
A
CN IV
6
Q
This nerve supplies the lateral rectus muscle
A
CN VI
7
Q
CN III innervates all extraocular muscles except these two
A
Superior oblique (CN IV)
Lateral rectus (CN VI)
8
Q
This extraocular muscle acts in elevation and intorsion
A
Superior rectus
9
Q
This extraocular muscle acts in depression and extorsion
A
Inferior rectus
10
Q
This extraocular muscle acts in elevation and extorsion
A
Inferior oblique
11
Q
This extraocular muscle acts in depression and intorsion
A
Superior oblique
12
Q
Eye movement that is rapid; change the direction of visual fixation
Ballistic
A
Saccades
13
Q
This is the type of eye movement that occurs during REM sleep
A
Saccades
14
Q
Type of eye movement for slower tracking movements; used to keep fovea on target
A
Smooth pursuit
15
Q
Is saccades eye movement voluntary or reflexive?
A
Can be either
16
Q
Is smooth pursuit eye movement voluntary or reflexive?
A
Voluntary
17
Q
Type of eye movement that align the fovea of each eye with targets located at different distances
Disconjugate movements
A
Vergence
18
Q
Types of eye movements that move the eyes to stabilize gaze relative to the external world
Compensate for head movements
Prevent retinal slipping
A
Vestibulo-ocular and Optokinetic
19
Q
Vestibulo-ocular (VOR) eye movement is based on sensory information from this
A
Semicircular canals
20
Q
Optokinetic (OKN) eye movement is based on this
A
Large portions of the visual field moving
21
Q
This type of eye movement is a physiologic or normal nystagmus
A
Optokinetic (OKN)
22
Q
Saccades eye movements are controlled by local neuron circuits in these two gaze centers
A
Paramedian pontine reticular formation (PPRF or horizontal gaze center)
Rostral interstitial nucleus (RIN or vertical gaze center)
23
Q
This is the horizontal gaze center
A
Paramedian pontine reticular formation (PPRF)
24
Q
This is the vertical gaze center
A
Rostral interstitial nucleus (RIN)
25
The rostral interstitial nucleus (RIN or vertical gaze center) is located in this structure
Midbrain
(next to the oculomotor nucleus)
26
The rostral interstitial nucleus (RIN or vertical gaze center) is located next to this cranial nerve nucleus
CN III
27
Is Paramedian nucleus an example of a nuclear or supranuclear pathway?
Supranuclear
(nuclear would be like abducens nucleus to lateral rectus muscle)
28
Is the Medial longitudinal fasciculus (MLF) a nuclear, supranuclear, or infranuclear pathway?
Infranuclear
(connects the CN VI to the CN III nuclei)
29
Lesions of the neural circuitry underlying saccades and gaze result in this symptom
Dysconjugate gaze
(leading to diplopia)
30
What does the Red glass test determine?
Type of dipolopia
(after lesion to circuitry underlying saccades)
31
This is dysconjugate gaze at rest
Strabismus
32
This cranial nerve palsy can cause horizontal diplopia
CN VI
(from impaired abduction of affected eye)
33
This palsy is impaired abduction of right eye and impaired adduction of left eye, so that the gaze towards the side of the lesion is impaired
Right lateral gaze palsy
34
In Right lateral gaze palsy, is gaze preference ipsilateral or contralateral to the lesion?
Contralateral
(gaze towards the side of the lesion is impaired)
35
Right lateral gaze palsy can be caused by lesion to either of these 2 structures
CN VI nucleus
PPRF (paramedian pontine reticular formation - horizontal gaze center)
36
This is impaired adduction of the left eye (horizontal diplopia), and nystagmus in the right eye
Left internuclear ophthalmoplegia (INO)
37
Lesion to this causes Left internuclear ophthalmoplegia (INO)
Left MLF
38
What causes nystagmus in internuclear ophthalmoplegia (INO)?
Brain tries to compensate for adduction weakness by increasing innervation to the adducting eye
(Hernig's law of equal innervation)
39
This would be a probable cause of internuclear ophthalmoplegia (INO) in older patients
Unilateral stroke
(MS would be suspected in younger patients)
40
One and a half syndrome is due to a unilateral lesion to this structure
Pons
41
One and a half syndrome involves a loss of both voluntary abduction and adduction on the side of the lesion (the “one”) and a loss of adduction or abduction on the contralateral side (the “one-half”)?
Loss of Adduction
42
Does damage to CN III cause medial or lateral strabismus?
Lateral (lateral gaze preference at rest)
43
Damage to this cranial nerve can cause mydriasis
CN III
44
This type of diplopia occurs with CN III damage
Diagonal diplopia
45
This type of diplopia occurs with CN IV damage
Vertical
46
CN IV nucleus lesion affects the ipsilesional or contralesional eye?
Contralateral
47
CN IV nerve lesion affects the ipsilesional or contralesional eye?
Ipsilesional
48
Damage to either of these 2 lobes can result in abnormalities in smooth pursuit eye movements
Occipital and parietal
49
Amount of binocular disparity is used by these regions to determine whether eyes should diverge or converge
Extrastriate
50
Information about location of retinal activity is relayed through this to cortex, where information from the two eyes is integrated
Lateral geniculate nucleus of thalamus
51
Lesions in this CN nucleus or the MLF in this structure will cause bilateral vestibulo-ocular reflex (VOR) deficits
MLF in the pons or CN VI nucleus
52
Lesions in this CN nucleus or the MLF in this structure will cause ipsilesional vestibulo-ocular reflex (VOR) deficits
MLF in the midrain or CN III nucleus
53
In lesions of the MLF in the pons or CN VI nucleus, direction of deficit is towards or away from the side of the lesion?
Towards
54
In lesions of the MLF in the midbrain or CN III nucleus, direction of deficit is towards or away from the side of the lesion?
Away from
55
Does this describe the results of lesion of the MLF in the pons or midbrain:
Bilateral VOR deficits
Pons
56
Does this describe the results of lesion of the MLF in the pons or midbrain:
Direction of deficit towards the side of the lesion
Pons
57
Does this describe the results of lesion of the MLF in the pons or midbrain:
Lesion will be on opposite side to the direction of head turn that revealed the VOR deficit
Pons
58
Does this describe the results of lesion of the MLF in the pons or midbrain:
Loss of VOR in ipsilesional eye
Midbrain
59
Does this describe the results of lesion of the MLF in the pons or midbrain:
Direction of deficit away from side of lesion
Midbrain
60
Does this describe the results of lesion of the MLF in the pons or midbrain:
The lesion is on the same side as the direction of head movement that revealed the VOR deficit
Midbrain
61
Does this describe the results of lesion of the CN III or CN VI nucleus:
Bilateral VOR deficits
CN VI
62
Does this describe the results of lesion of the CN III or CN VI nucleus:
Loss of VOR in ipsilesional eye
CN III
63
Does this describe the results of lesion of the CN III or CN VI nucleus:
Direction of deficit towards the side of the lesion
CN VI
64
Does this describe the results of lesion of the CN III or CN VI nucleus:
Direction of deficit is away from the side of lesion
CN III
65
For involuntary/reflexive saccades, PPRF receives input from this structure
Contralateral superior colliculus
66
Lesions of this structure will result in deficits in involuntary saccades
Superior colliculus
67
For voluntary saccades, gaze centers receive input from this
Contralateral frontal eye field (FEF)
(in frontal cortex)
68
Lesions to this result in impairment of voluntary saccades into contralesional space
Frontal eye fields
69
Do lesions of the frontal eye fields result in gaze preference towards or away from the side of the lesion?
Towards
(there is impairment of voluntary saccades into contralesional space)
70
Right way eyes indicate a lesion at this level
Cortical
71
Wrong way eyes indicate a lesion at this level
Brainstem
72
Does lesion at cortical level result in right way or wrong way eyes?
Right way
73
Does lesion at brainstem level result in right way or wrong way eyes?
Wrong way
74
In right way eyes, is gaze preference towards or away from the side of weakness?
Away from
75
In wrong way eyes, is gaze preference towards or away from the side of weakness?
Towards
76
In right way eyes, is gaze preference towards or away from the side of lesion?
Towards
77
Is constriction or dilation of eye pupil controlled by sympathetics?
Dilation
(axons not in CN III - instead in ophthalmic nerve)
78
Is constriction or dilation of eye pupil controlled by parasympathetics?
Constriction
(by CN III)
79
Is constriction of the eyes controlled by sympathetics or parasympathetics?
Parasympathetics (CN III)
80
Is dilation of the eyes controlled by sympathetics or parasympathetics?
Sympathetics (ophthalmic nerve)
81
This muscle adjusts the thickness of the lenses during accommodation
Mediated by Ed-West nucleus of parasympathetic division, carried via CN III
Ciliary muscle
82
Is the ciliary muscle controlled by sympathetics or parasympathetics?
Parasympathetics
(Ed-West nucleus of CN III)
83
Are neurons from posterior hypothalamus involved in sympathetic or parasympathetic control of pupillary reflex?
Sympathetic
84
Is the Ciliospinal center of budge involved in sympathetic or parasympathetic control of pupillary reflex?
(is in the spinal cord, segments C8-T2)
Sympathetic
85
Do neurons synapse onto superior cervical ganglion in sympathetic or parasympathetic control of pupillary reflex?
Sympathetic
86
Is the ophthalmic nerve involved in sympathetic or parasympathetic control of pupillary reflex?
Sympathetic
87
This is a condition where the pupils can be different sizes
Produced by Edinger-Westhphal nucleus or CN III
Anisocoria
88
Lesions to either of these can produce Anisocoria
Edinger-Westphal nucleus or CN III
89
Impaired consensual constriction of the ipsilesional pupil can be caused by lesion to this nerve
CN III
90
Is Anisocoria a sympathetic or parasympathetic lesion of the pupillary reflex?
Parasympathetic
91
Is Horner's syndrome a sympathetic or parasympathetic lesion of the pupillary reflex?
Sympathetic
92
In Horner's syndrome, ptosis occurs due to loss of innervation to this
Smooth muscle in upper lid
93
In Horner's syndrome, miosis occurs due to loss of sympathetic innervation to this
Pupillary dilator muscle
94
In Horner's syndrome, Anhidrosis occurs due to loss of this
Sympathetic innervation
95
Can identify pre vs. post superior cervical ganglion sympathetic lesions of pupil reflex (e.g. Horner's syndrome) using these eye drops
Hydroxyamphetamine
(stimulate NE release)
Eye will dilate if lesion is preganglionic (but not if post)
96
In using hydroxyamphetamine eye drops to assess a sympathetic lesion to the pupil reflex, will the eye dilate if the lesion is pre- or post-ganglionic?
Pre
97
Bilateral lesions of this structure will cause both pupils to be small, but still reactive to light
Pons
98
Accommodation occurs by this muscle
Lens ciliary muscle
99
In accommodation, constriction is activated by visual cortex and related to this same structure used in light reflex
Pretectal nuclei
(parasympathetic/ciliary ganglion)
100
The blink/corneal reflex is often accompanied by parasympathetic activation of this gland
Lacrimal gland (tear reflex)
