Examination methods
It is especially important to take the patient's history carefully and to perform neuro-ophthalmological and neuro-otological examinations when a patient ambiguously reports feeling "dizzy".The history and the clinical examination should first differentiate between peripheral vestibular and central vestibular forms of vertigo.
Other additional laboratory tests are in most cases of less clinical importance.
Most disorders of the oculomotor system, the peripheral or central vestibular systems, and the control of stance and posture can be identified during a careful examination, even without recording the eye movements. These disorders can also be attributed topographically to the correct site. The following figures illustrate details of the examination procedure, the essential findings, and their interpretation. The important questions to be asked in the neuro-ophthalmological examination are the following:
1. Does a spontaneous nystagmus (e.g., upbeat nystagmus due to a medullary lesion or horizontal-rotatory nystagmus in vestibular neuritis), or positioning nystagmus (e.g., BPPV) occur?
2. Are there signs of vestibular disorders or disorders of the ocular motor system (e.g., double vision, saccadic pursuit, slowed or dysmetrical saccades, gaze-evoked nystagmus) or other neurological symptoms (e.g., facial paresis, perioral paresthesias, dysarthrophonia, dysphagia) that indicate a central origin of the disorder?
Examination procedure for the oculomotor and vestibular systems |
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Type of examination |
Check for |
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Determine: |
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| Body and head posture |
tilt or turn of the head / body postural anomaly |
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Position / motility of the eyes: |
Check for |
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Position of the eyes during gaze straight ahead Cover test Examination of the eyes in eight end positions (binocular and monocular)
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misalignment nystagmus misalignment and latent nystagmus, the range of eye movements, end-point and nystagmus |
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Gaze-holding function: |
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Gaze in a 10-40 degree horizontal direction or 10-20 degree vertical direction and back to zero
Smooth pursuit:Horizontal and vertical |
gaze-evoked nystagmus, rebound nystagmus saccadic smooth pursuit |
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Saccades |
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Horizontal and vertical saccades when looking around and when directed at targets
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latency, speed, accuracy, and conjugate movements |
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Optokinetic nystagmus (OKN): |
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Horizontal and vertical nystagmus when looking at an optokinetic drum or tape |
inducible, beating direction, and phase (reversal?) |
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Peripheral vestibular function: |
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Clinical testing of the vestibulo-ocular reflex (VOR) Halmagyi's head-impulse test: rapid turns of the head while fixating stationary target
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unilateral or bilateral peripheral vestibular lesion
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Fixation suppression of the vestibulo-ocular reflex: |
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| Turns of the head while fixating a spot moving with the same velocity | disturbance of fixation suppression |
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Examination with Frenzel's glasses: |
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Gaze straight ahead, to the right, to the left, downwards, upwards and head-shaking test
Eye movements induced by changes in middle-ear pressure (with Politzer balloon) |
spontaneous nystagmus
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Positioning maneuver (with Frenzel's glasses): |
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To the left and to the right in head-hanging position, during turns around the longitudinal axis of the body
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positioning nystagmus, central positional nystagmus
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Stance and posture control: |
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Romberg test |
swaying, tendency to fall |
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