Oculomotor Exam Flashcards
(128 cards)
1
Q
Spontaneous Nystagmus =
A
At rest — without any movement
Peripheral lesion (UVH) ➔ spontaneous horizontal nystagmus (fast phase toward healthy ear).
Central lesion ➔ spontaneous vertical or direction-changing nystagmus.
2
Q
Gaze-Evoked Nystagmus =
A
Peripheral nystagmus ➔ stronger when gazing toward fast phase (Alexander’s Law).
Central nystagmus ➔ may change direction depending on gaze.
3
Q
Smooth Pursuits =
A
Normal = smooth, fluid tracking.
Abnormal (saccadic pursuit) = jerky, broken tracking — suggests central pathology (brainstem or cerebellum issue).
4
Q
Saccades =
A
Normal = rapid, accurate eye movements.
Abnormal = overshooting (hypermetric) or undershooting (hypometric) = central lesion (brainstem, cerebellum).
5
Q
VOR Cancellation =
A
Normal = eyes stay fixed on target while you move their head and body together.
Abnormal = eyes can’t stay fixed, suggests central dysfunction (cerebellar issue).
6
Q
In ___ vestibular dysfunction, VOR cancellation is usually normal.
A
peripheral
7
Q
Nystagmus
RED FLAG =
A
Down-beating nystagmus or direction changing nystagmus indicate CNS pathology and need referral/imaging
8
Q
Videonystagmography (VNG)?
A
specialized test that:
Measures eye movements (nystagmus).
Assesses how well the vestibular system (especially the horizontal canals) is working.
9
Q
What is Caloric Testing (part of VNG)?
A
Caloric Testing stimulates the horizontal semicircular canals individually by changing the temperature of the external auditory canal.
Warm or cool water (or air) is flushed into the ear to provoke endolymph flow → triggering nystagmus.
10
Q
Warm water/air =
A
Excites vestibular nerve on that side (causes nystagmus toward the stimulated ear).
11
Q
Cool water/air =
A
Inhibits vestibular nerve on that side (causes nystagmus away from the stimulated ear).
12
Q
COWS =
A
Cold Opposite
Warm Same
(direction of fast phase nystagmus)
13
Q
___ responses asymmetric -> unilateral vestibular hypofunction
A
*>20%
= If one side is weaker by more than 20% compared to the other, that is considered abnormal.
14
Q
If a patient has no nystagmus on caloric stimulation →
A
that side’s vestibular system isn’t working.
15
Q
Caloric Testing
Normal nystagmus
A
Normal peripheral vestibular function
16
Q
Caloric Testing
Reduced or absent nystagmus in one ear
A
Unilateral hypofunction (e.g., vestibular neuritis)
17
Q
Caloric Testing
Reduced/absent responses in both ears
A
Bilateral vestibular hypofunction
18
Q
Caloric Testing
Direction-changing or vertical nystagmus
A
Central pathology
19
Q
Some Vestibular Tests Are Done in Ambient Light (Normal Visual Fixation):
A
Tests are performed in regular lighting (natural light or room lights).
The patient can use their eyes normally to stabilize gaze.
Their visual fixation can suppress nystagmus or compensate for mild vestibular deficits.
20
Q
Examples of tests done in ambient light:
A
Head Impulse Test (HIT)
Dynamic Visual Acuity (DVA)
Smooth Pursuits and Saccades (oculomotor exam)
21
Q
If you test someone in normal light, you might ____ because the patient can suppress it with their eyes.
A
miss mild spontaneous nystagmus
22
Q
Why remove fixation?
A
Vision can hide mild vestibular dysfunction by helping patients stabilize themselves.
Taking away visual fixation forces the vestibular system to show its true weakness — you uncover hidden nystagmus or abnormal eye movements.
23
Q
Equipment that removes fixation:
A
Frenzel lenses (big magnifying goggles that blur vision)
Video infrared goggles (allow examiner to see eye movements in darkness)
24
Q
Examples of tests that require removal of fixation:
A
Spontaneous nystagmus testing (in dark)
Head-shaking nystagmus test
Positional testing (like Dix-Hallpike) sometimes enhanced with goggles
25
When visual fixation is removed =
any underlying spontaneous nystagmus becomes much more obvious
26
___ nystagmus typically increases without fixation.
Peripheral
27
___ nystagmus often persists even with fixation.
Central
28
A patient with vertigo due to a ___ vestibular origin might have no obvious spontaneous nystagmus on clinical examination with the naked eye
peripheral
29
What is Spontaneous Nystagmus?
Involuntary rhythmic eye movements at rest, without head movement or position change.
Fast phase in one direction, slow phase in the opposite direction.
It gives clues about whether the issue is peripheral (ear/nerve) or central (brainstem/cerebellum).
Tested with:
Without fixation ideally (Frenzel lenses, infrared goggles).
30
Nystagmus observed in ambient light in conjunction with other tests =
Abnormal smooth pursuit
Abnormal saccadic eye movement
Abnormal VOR cancellation
Patient may have known neurologic condition that clinician is aware of (stroke/TBI)
Patient presents with central vestibular signs and needs MD referral
31
Nystagmus observed with goggles on =
Patient may have acute (not yet compensated by CNS) peripheral hypofunction
Patient presents with central vestibular signs and needs MD referral
32
Spontaneous Nystagmus
Peripheral vs Central
direction:
P: Unidirectional (same direction no matter where patient looks)
C: Can change directions depending on gaze
33
Spontaneous Nystagmus
Peripheral vs Central
type:
P: Mostly horizontal with a slight torsional component
C: Pure vertical (upbeat, downbeat) or pure torsional possible
34
Spontaneous Nystagmus
Peripheral vs Central
behavior:
P: Suppressed with visual fixation (room lights, focusing)
C: NOT suppressed by visual fixation
35
Spontaneous Nystagmus
Peripheral vs Central
example:
P: Acute unilateral vestibular hypofunction (vestibular neuritis)
C: Brainstem or cerebellar lesions
36
Spontaneous Nystagmus
Peripheral vs Central
other:
P: Follows Alexander’s Law (nystagmus gets stronger when looking toward fast phase side)
C: May also have other neuro signs: ataxia, diplopia, dysarthria, weakness
37
_____ = same direction always, horizontal/torsional, suppressed by fixation.
Peripheral
38
____ = vertical or direction-changing, not suppressed by vision.
Central
39
Peripheral Pattern =
Horizontal-torsional nystagmus
Fast phase toward healthy ear (if acute UVH)
Increases when gaze toward fast phase side
Decreases or disappears with fixation
No major neurological signs
40
Peripheral Pattern
seen in:
Vestibular neuritis
Labyrinthitis
Acute stage of Meniere’s attack
41
Central Pattern =
Pure vertical (up-beating or down-beating) nystagmus
Direction-changing nystagmus with gaze changes
No suppression with fixation
Associated neurological deficits (ataxia, dysarthria, weakness)
42
Central Pattern
seen in:
Brainstem stroke
Cerebellar infarct
MS
Tumors
43
Ambient light + abnormal pursuits/saccades/VOR cancel =
Central cause (brain, brainstem)
Refer to MD
44
Only with goggles (no fixation)
=
Peripheral vestibular loss (ear/nerve)
Treat with vestibular rehab
45
What is Gaze-Evoked Nystagmus (GEN)?
Nystagmus that appears only when the patient gazes away from their primary straight-ahead position.
Patient looks left, right, up, or down, and you observe if nystagmus develops or changes.
46
GEN ✅ Big Difference from Spontaneous Nystagmus:
Spontaneous nystagmus = present at rest.
Gaze-evoked nystagmus = only present (or changes) when gazing in a certain direction.
47
Normal Variant (End-Point Nystagmus) =
Mild horizontal nystagmus when looking far lateral (e.g., 30–40°).
Fatigue quickly after a few seconds.
Symmetrical in both directions.
Not pathological — considered a normal finding.
Seen in healthy people, especially when looking far out to the side for a prolonged time.
48
Abnormal Gaze-Evoked Nystagmus (Pathological) =
Nystagmus appears or changes direction depending on gaze.
Stronger and more persistent.
Asymmetrical between sides (strong in one gaze direction, weak or absent in the other).
Does not fatigue quickly.
Can be horizontal, vertical, or torsional.
49
Normal endpoint nystagmus =
Mild, symmetric, fatigues
cause: normal
50
Abnormal gaze-evoked nystagmus =
Strong, persistent, asymmetric, direction-changing
cause: central
51
Gaze-evoked nystagmus that’s persistent, direction-changing, or asymmetric =
is a central sign ➔ needs referral
52
Nystagmus from ___ lesion follows Alexander’s Law
PERIPHERAL
53
Three Main Parts of Alexander’s Law:
Direction of Nystagmus
Gaze Dependency
Effect of Visual Fixation
54
Direction of Nystagmus:
The fast phase of nystagmus beats toward the healthy/uninjured side.
So if the right ear is damaged, the nystagmus beats to the left (healthy side).
✅ (Remember: nystagmus is named for the fast phase direction.)
55
Gaze Dependency:
The nystagmus gets stronger when gazing toward the fast phase (healthy side) and
➔ Gets weaker or disappears when gazing toward the slow phase (injured side).
56
if it’s a right ear injury:
Looking to the left (healthy side) → nystagmus gets stronger.
Looking to the right (injured side) → nystagmus gets weaker.
57
The amplitude of the nystagmus is ___
gaze-dependent
58
Effect of Visual Fixation:
➔ Visual fixation suppresses nystagmus.
➔ When fixation is removed (e.g., using infrared goggles), nystagmus becomes stronger.
59
___ movements allow the eyes to smoothly track a moving target.
Smooth pursuit
60
How to test smooth pursuits:
Move your finger or pen horizontally and vertically slowly (~20° per second).
Patient follows the target with only their eyes — no head movement.
61
Smooth pursuits
Normal finding:
Smooth, steady, continuous eye movement following the target without jerks.
61
Smooth pursuits
Abnormal finding:
Saccadic intrusions (little "catch-up" jerks as the eye tries to follow).
Eyes jump instead of gliding smoothly.
62
Abnormal smooth pursuits suggest ___
central pathology (brainstem or cerebellar dysfunction)
63
___ is the inward movement of both eyes toward each other when focusing on a near object (e.g., bringing a finger closer to the nose).
Convergence
64
How to test Convergence:
Hold a pen or finger about 18–24 inches away and slowly move it toward the patient's nose.
Ask them to keep focusing on it.
65
Convergence
Normal finding:
Both eyes move inward symmetrically and maintain fixation until the object is very close (~5–10 cm from nose).
66
Convergence
Abnormal finding:
One or both eyes drift outward instead of maintaining inward focus.
Diplopia (double vision) may occur if convergence breaks down too early.
67
Abnormal convergence suggests ____
central dysfunction — often midbrain problems (where convergence reflex pathways are located).
68
When you check smooth pursuits, you are assessing:
Is the movement smooth or jerky?
Smooth = normal
Jerky (saccadic intrusions) = abnormal (points toward central nervous system dysfunction).
69
Smooth pursuit requires coordination of:
Brainstem (pons, midbrain)
Cerebellum
Cortical areas (frontal eye fields)
70
When you check convergence, you are assessing:
Can both eyes move inward smoothly and symmetrically?
At what distance does the patient report double vision (diplopia)?
71
Normal near point of convergence:
About 5–10 cm from the tip of the nose.
72
CN III (Oculomotor) =
Controls most of the eye muscles, especially convergence (medial rectus muscles pulling eyes inward)
73
CN IV (Trochlear) =
Assists with vertical eye movement (superior oblique muscle — important for pursuits when looking downward)
74
CN VI (Abducens) =
Controls lateral eye movement (lateral rectus muscle — outward gaze, smooth pursuits side-to-side)
75
CN for smooth pursuits:
CN III, IV, VI
75
CN for convergence:
CN III (Oculomotor)
76
___ are quick, simultaneous movements of both eyes between two points of fixation
Saccades
77
How to Perform the Saccadic Eye Movement Test:
PT stands about 18 inches (45 cm) away from the patient.
Hold up two targets (e.g., index fingers, thumbs, or small objects) about 12–18 inches apart horizontally or vertically.
78
abnormal saccades =
Eye takes multiple small movements ("steps") to get to target
Overshooting target (hypermetric) or undershooting (hypometric)
79
Overshoot (hypermetric saccades):
Eyes go too far, then correct backward.
80
Undershoot (hypometric saccades):
Eyes fall short, then correct with a second movement
80
What is VOR Cancellation?
VOR Cancellation tests whether a person can inhibit (cancel) their vestibulo-ocular reflex (VOR) while the head and body are moving together.
81
Why test VOR Cancellation?
Normally, if you turn your head, your eyes reflexively move in the opposite direction to keep gaze stable (VOR).
But sometimes (like tracking a moving object while turning your head) you need to suppress VOR and keep your eyes moving with your head.
✅ Cancellation is a brain task, not an ear task — it requires a healthy cerebellum (especially the flocculus/paraflocculus).
82
How to Perform the VOR Cancellation Test:
Patient sits upright.
Hold your thumbs or small object at arm’s length in front of them.
Ask the patient to fix their gaze on their own thumbs (or a small object).
83
What is the Head Impulse Test (HIT)?
A quick passive head movement test that checks whether the VOR (vestibulo-ocular reflex) is functioning properly.
Specifically tests the horizontal semicircular canals and superior vestibular nerve function.
84
How to Perform the Head Impulse Test:
Patient sits upright, looking at your nose (a fixed target).
Tell them:
➔ "Keep your eyes on my nose — no matter what."
The patient must relax their neck.
You move their head, not them.
Hold the patient's head firmly on both sides.
Turn the head quickly and unpredictably about 10–20 degrees to the left or right.
Movements must be small and sharp — like a sudden "jerk," not slow.
85
Eyes jump back to target after head turn (corrective saccade) =
Abnormal HIT → indicates peripheral hypofunction on the side you turned toward
86
If the head is thrust to the right and you see a corrective saccade, the ___ vestibular system is weak.
right
87
Corrective saccades can be:
Overt: Big visible eye jump after head movement.
Covert: Tiny corrective eye movements during the head movement (harder to catch without high-speed video).
88
Head Impulse Test: Interpretation
Positive test: eyes will move off target, delay in returning to target
delay will occur on impaired side
Unilateral (or bilateral) peripheral hypofunction
89
What is Head Shaking Nystagmus (HSN)?
A test where you shake the patient's head rapidly back and forth to "stress" the vestibular system —
then stop suddenly to see if nystagmus appears.
Reveal asymmetric vestibular function between the two sides.
If one vestibular system is weak, head shaking will unmask it.
90
How to Perform the Head Shaking Test:
Patient sits upright.
Patient's eyes are either:
Closed (preferred) during the shaking.
Or using infrared goggles to block visual fixation.
Hold the patient’s head.
Flex the neck forward about 30° (this puts the horizontal semicircular canals in the optimal plane).
Oscillate (shake) the head rapidly side-to-side (yaw plane) at about 2 Hz (2 cycles per second) for 20 cycles.
91
If After Shaking...
Horizontal nystagmus (toward healthy side) =
Peripheral hypofunction (UVH)
92
If After Shaking...
No nystagmus =
Normal vestibular system
93
If After Shaking...
Vertical or direction-changing nystagmus =
Central disorder
94
Head Shaking Nystagmus: Interpretation
Positive: nystagmus beats towards the intact neural side
Contralateral side has hypofunction
Typically coincides with positive head thrust test and patient history
Unilateral hypofunction
95
What is Dynamic Visual Acuity (DVA)?
DVA tests how well a patient can maintain clear vision while their head is moving.
It indirectly measures vestibulo-ocular reflex (VOR) function.
Identify gaze instability (oscillopsia) caused by vestibular hypofunction.
96
If ___ is weak → the eyes can’t stabilize images → vision blurs when head moves.
VOR
97
How to Perform the Dynamic Visual Acuity Test:
Patient sits 15-20 ft from eye chart
Ask patient to read lowest line they can clearly see
Manually move patient’s head quickly side to side at speed of 2HZ or 120 beats/min as they read from top to bottom
Note the difference between static (head sable) line and dynamic (head moving line)
98
DVA: Interpretation
Normal: 2 or less line difference
Abnormal: 3 lines of greater
Decreased VOR
Possible peripheral hypofunction
Possible underlying central dysfunction
99
What is Hyperventilation Induced Nystagmus (HIN)?
Hyperventilation: ventilation that exceeds metabolic needs
Increases serum pH, lowers the concentration of ionized calcium
reduces both the cerebral and inner ear circulation and reduces the tissue oxygenation
lowers both middle ear pressure and intracranial pressure
can be used in the bed-side examination of vertiginous patients to reveal latent cerebellar or vestibular disease/dysfunction (Hyperventilation Induced Nystagmus (HVIN) in normal subjects is low )
100
How to Perform the Hyperventilation Test:
Patient is seated upright.
Ask them to breathe deeply and rapidly (about 1 breath every 2 seconds) for 30–60 seconds.
Observe the patient's eyes for nystagmus.
Ask if they feel increased dizziness or vertigo symptoms.
101
Hyperventilation changes blood pH (respiratory ___).
alkalosis
102
Hyperventilation Test
Results:
Horizontal nystagmus or vertigo appears = Possible peripheral vestibular hypofunction (especially acoustic neuroma)
Vertical or strong torsional nystagmus = Possible central pathology
No symptoms or nystagmus = normal
103
____ can cause nystagmus to emerge after hyperventilation.
Peripheral vestibular weakness (e.g., vestibular schwannoma, demyelination of vestibular nerve)
104
_______ can also cause abnormal responses — but look for vertical/torsional or very strong unusual patterns.
Central lesions
105
You will NOT perform Hyperventilation Testing in your PT exams.
t's a medical diagnostic tool used occasionally at the bedside —
Not part of typical PT vestibular screening or treatment protocols.
106
What is the Fukuda Step Test?
A standing balance test where the patient marches in place with eyes closed, to see if they rotate or drift toward one side.
It assesses for asymmetrical vestibulospinal reflex function.
107
How to Perform the Fukuda Step Test:
Patient stands upright with arms extended straight out in front at shoulder level.
Eyes closed.
Head held neutral (don't tilt up/down).
Shoes off if possible for better proprioception elimination.
Ask the patient to march in place, lifting their knees about 30°, for 50 steps (takes about 60 seconds).
Do NOT give corrections while they're moving.
Ideally, place markers or have them start in a defined spot.
108
Fukuda Step Test
Results:
Rotates more than 30 degrees to one side = Suggests unilateral vestibular hypofunction (turns toward weaker side)
Drifts laterally = Could also suggest unilateral dysfunction or somatosensory/vestibular imbalance
Minimal/no rotation = normal
109
Fakuda test:
Patients rotate ___ the side of the vestibular lesion.
toward
110
Main Goals of Balance and Gait Testing for Vestibular Patients:
Static postural control (standing still)
Dynamic postural control (moving, changing direction, walking)
Functional gait (speed, quality, stability during ambulation)
Patient’s self-perceived balance confidence and dizziness handicap
111
Static Postural Control Testing
Key Tool:
Modified Clinical Test of Sensory Interaction on Balance (mCTSIB)
112
What is mCTSIB?
Assesses how well a patient uses vision, vestibular input, and somatosensory input for balance.
Four conditions:
Firm surface, eyes open
Firm surface, eyes closed
Foam surface, eyes open
Foam surface, eyes closed (vestibular reliance condition)
113
Difficulty on foam with eyes closed suggests ___ dysfunction.
vestibular
114
Dynamic Postural Control / Gait Testing
Key Tools:
Functional Gait Assessment (FGA)
Dynamic Gait Index (DGI)
115
What is FGA?
Expanded version of the DGI — includes tougher tasks (like walking with eyes closed, walking backwards).
10 tasks scored 0–3 each (higher = better).
116
What is DGI?
Tests functional gait by challenging balance during walking:
Gait with head turns
Stepping over obstacles
Speed changes
117
Difficulty with head turns during gait → suggests ___ impairment.
vestibular
118
Fall Risk Cut-Offs:
FGA ___ = increased fall risk
DGI ___ = increased fall risk
FGA <22/30 = increased fall risk
DGI <19/24 = increased fall risk
119
Self-Perceived Outcome Measures (Patient-Reported Questionnaires)
Key Tools:
Dizziness Handicap Inventory (DHI)
Activities-specific Balance Confidence Scale (ABC Scale)
Vestibular Disorders Activities of Daily Living Scale (VADL)
120
Dizziness Handicap Inventory (DHI) =
Measures perceived impact of dizziness on physical, emotional, and functional levels
121
Activities-specific Balance Confidence Scale (ABC Scale) =
Measures patient's confidence in performing daily tasks without losing balance.
122
Vestibular Disorders Activities of Daily Living Scale (VADL) =
Measures perceived difficulty in self-care, mobility, and instrumental activities.
123
Main Goals of Therapy for UVH:
Gaze stability (via VOR retraining)
Postural control (dynamic balance)
Symptom reduction (decrease dizziness, motion sensitivity)
Functional mobility (return to safe ambulation and activities)
124
VORx1:
➔ Head moves, eyes stay locked on a stationary target (e.g., letter on a wall).
125
VORx2:
➔ Head and target move in opposite directions (much harder — usually later phase rehab).
