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CENTRAL VS. PERIPHERAL VERTIGO |
Vertigo refers to the subjective
feeling of movement of self or the environment in the absence of true movement.
Vertigo is a frequent symptom that results from a variety of etiologies, some
benign and others serious. One of the more important differentiating features is
determining if the vertigo has a peripheral or central etiology. Making this distinction is very important as the causes, and thus clinical
management of peripheral versus central vertigo, can vary significantly.
Peripheral vertigo generally refers to
vertigo which arises from dysfunction of the vestibular apparatus in the inner
ear (figure below) or its connecting vestibular nerve (CN VIII). In addition to
hearing, the inner contains the bony labryinth where the semicircular canals and
utricle/saccule are located. These structures sense linear and angular motion,
and are essential in the maintenance of balance and various vestibular reflexes. |
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Central vertigo results from dysfunction
of the central connections of the vestibular apparatus including the vestibular
nuclei in the brainstem and their connections, especially to the cerebellum. The
vestibular nerve (CN VIII) is usually considered part of the peripheral
vestibular system (essentially being a peripheral nerve). However, in the case
of an acoustic neuroma of CN VIII, if the neuroma is large, it can compress the
cerebellopontine angle and result in central vertigo as
well. The diagram below summarizes some
of these pathways (you do not need to memorize these for the exam). |
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DIFFERENTIAL DIAGNOSIS OF VERTIGO |
Peripheral |
Central |
Benign Paroxysmal Positional Vertigo (BPPV) |
Vertebrobasilar ischemic stroke (cerebellar, brainstem) |
Labyrinthitis (viral or post-infectious) |
Vertebrobasilar hemorrhagic stroke (cerebellar, brainstem) |
Meniere’s disease |
Demyelinating (multiple sclerosis) |
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Tumor – of the cerebellar-pontine angle, brainstem or
cerebellum. |
CN VIII tumor |
Migraine (vertebrobasilar) |
Perilymphatic fistula |
Partial seizure |
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Infection (abscess) |
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Neurodegenerative disease involving brainstem
and/or cerebellum |
Drug-induced (e.g., aminoglycosides) |
Drug induced (e.g., anticonvulsants) |
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The diagram above illustrates the Dix-Hallpike
maneuver (also known as the Barany
maneuver), a provocative test to try to reproduce the patient’s
vertigo. The findings can be helpful in differentiating a peripheral from
central cause of vertigo. (A) The patient begins in the sitting up position. The
examiner turns the patient’s head 45 degrees from the midline.
(B) Next, with the
head kept 45 degrees from the midline on either side, the patient is leaned back
with head tilted back and one ear directed to the ground. The patient keeps eyes
open during the test. The examiner checks for the following:
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Latency of nystagmus (time to onset of
nystagmus)
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Duration of nystagmus
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Direction of fast phase of nystagmus
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Reproducibility of the patient’s symptoms/signs
(e.g., nausea, vomiting, vertigo, nystagmus)
• Fatiguability
of the response (lessening of provocative response with repetition of the
maneuver)
The table below summarizes the findings from the patient's history,
examination and/or provocative maneuvers that help differentiate peripheral versus central pathology.
CLINICAL DIFFERENTIATION OF
PERIPHERAL VERSUS CENTRAL VERTIGO |
Symptom / Sign |
Peripheral |
Central |
Latency of nystagmus with head movement |
Usually a latency; range 0-40 sec (mean 7.8) |
No latency; begins immediately |
Duration of symptoms |
< 1 minute |
Symptoms may persist |
Fatigability (lessening signs and symptoms with
repetition of provocative maneuver |
Yes |
No |
Nystagmus appearance and direction |
Fixed direction, usually torsional and horizontal |
Changing direction, often pure vertical, horizontal
or torsional |
Intensity of symptoms |
Severe vertigo, marked nystagmus, nausea, vomiting |
Usually mild vertigo, less nystagmus, rare nausea |
Reproducibility |
Inconsistent |
Consistent |
Fixation (eyes open, fixating on a distant object) |
Improves symptoms |
Little effect |
Hearing loss and/or tinnitus |
Common |
Uncommon |
Other brainstem signs (e.g., diplopia, facial
numbness, dysarthria, etc.) |
Absent |
May be present |
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Adopted from Bradley, Daroff et. al, Neurology
in Clinical Practice, 4th Edition. |
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