Download The 10-minute Examination of the Dizzy Patient

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The 10-minute
Examination of the Dizzy
Patient
The following is a suggested order of examination for eye
movement and posture control abnormalities in dizzy patients.
SPONTANEOUS NYSTAGMUS
Action:
Target fixation in neutral gaze
Frenzel goggles
Normal:
No nystagmus or excessive saccades
Abnormal: Jerk nystagmus: Direction fixed, increases with
Frenzel goggles = PERIPHERAL
Direction changing, increases with fixation =
CENTRAL (periodic alternating nystagmus, congenital)
Pendular = CENTRAL (congenital nystagmus)
GAZE NYSTAGMUS
Action:
Hold eccentric gaze 20–30 degrees for 10 seconds
in horizontal and vertical plane
Normal:
Physiologic end gaze or no nystagmus
Abnormal: Jerk nystagmus (exponentially decreasing slow
phase) in direction of gaze = CENTRAL (flocculus, drug effect, alcohol)
Downbeat nystagmus in lateral gaze = CENTRAL
(Arnold Chiari, midline cerebellum)
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Practical Management of the Dizzy Patient
SMOOTH PURSUIT
Action:
Track finger moving, 60 degrees through
60-degree arc horizontal and vertical
Normal:
Smooth pursuit movements
Abnormal: Saccadic pursuit = CENTRAL (cerebellum, brainstem, parietal lobe)
Irregular tracking = acuity, age, medications,
attention
SACCADES
Action:
Alternate gaze between fingers
Normal:
Rapid, accurate, conjugate eye movements
Abnormal: Overshoots, undershoots = CENTRAL (dorsal
vermis, fastigial nuclei)
Slow saccades = CENTRAL (brainstem)
Late saccades = CENTRAL (frontal lobe, brainstem, Parkinson’s syndrome)
Disconjugate = CENTRAL (MLF syndrome)
HEAD THRUST TEST
Action:
Thrust head 20–30 degrees while fixating on
target
Normal:
No loss of fixation
Abnormal: Refixation saccade = PERIPHERAL (loss of VOR)
HEADSHAKE TEST
Action:
Shake head for 20 seconds at 2 Hz (horizontal and
vertical) eyes closed, then open eyes (Frenzel goggles) and observe for nystagmus
Normal:
No nystagmus
Abnormal: Unidirectional nystagmus in plane of headshake =
PERIPHERAL (toward intact side except hydrops)
Vertical nystagmus after horizontal headshake =
CENTRAL
DYNAMIC VISUAL ACUITY TEST
Action:
Have patient read eye chart with head still then
with 0.2 Hz headshake
Normal:
<3 line drop in acuity with headshaking
Abnormal: <3 line drop with headshaking = PERIPHERAL
(bilateral VOR loss)
The 10-minute Examination of the Dizzy Patient
FIXATION SUPPRESSION TEST
Action:
Have subject fixate on own thumb while rotating
body in exam chair
Normal:
No nystagmus
Abnormal: Nystagmus in direction of rotation = CENTRAL
(flocculus)
POSITION TESTS
Action:
Place the head in left/right Hall pike, left/right
lateral, supine
Normal:
No nystagmus
Abnormal: Torsional (geotropic) nystagmus with upbeat and
ageotropic horizontal components = BPPN
(downmost posterior SCC)
Horizontal (geotropic or ageotropic) paroxysmal
nystagmus = BPPN (downmost lateral canal)
Horizontal sustained nystagmus = PERIPHERAL/
CENTRAL
AURAL PRESSURE/SOUND TESTS
Action:
Stimulate ear with positive pressure (otoscope),
loud sound, mastoid vibration
Normal:
No nystagmus
Abnormal: Upward deviation with ipsilateral eye torsion toward nose or downbeating nystagmus = superior
semicircular canal dehiscence
Horizontal nystagmus = perilymphatic fistula
CEREBELLAR LIMB TESTS
Action:
Finger-to-nose
Heel-shin
Rapid alternating motion
Normal:
Accurate movements
Abnormal: Dysmetria, dysdiadochokinesia
(lateral lobe cerebellum)
=
SOMATOSENSATION TESTS
Action:
128 Hz tuning fork to lateral malleolus
Normal:
Vibration sense present
Abnormal: Loss of vibration sense
Action:
Move great toe up/down
Normal:
Correctly identifies action
Abnormal: Incorrectly identifies action
CENTRAL
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Practical Management of the Dizzy Patient
POSTURE TESTS
Action:
Romberg test
Sharpened Romberg test
Eyes closed foam
Normal:
Minimal sway, no falls
Abnormal: Excessive sway, falls on Romberg = VARIABLE/
APHYSIOLOGIC
Falls on foam eyes closed = PERIPHERAL/
MIXED/APHYSIOLOGIC
GAIT TESTS
Action:
Observation of gait
Fukuda step test
Normal:
Normal gait
<45-degree rotation on Fukuda test
Abnormal: Wide based, ataxic, Parkinsonian, musculoskeletal
gait
>45-degree rotation on Fukuda test