CNS Causes of Vertigo Workup

Updated: Apr 12, 2022
  • Author: Marcelo B Antunes, MD; Chief Editor: Arlen D Meyers, MD, MBA  more...
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Laboratory Studies

Few laboratory studies facilitate the diagnosis of the CNS causes of vertigo.

If vertigo is accompanied by prolonged nausea and vomiting in elderly patients, monitoring and replacing fluids and electrolytes is prudent.

In the rare case of suspected Lyme neuroborreliosis, serology for Lyme disease with enzyme-linked immunosorbent assay (ELISA), Western blot analysis, and lymphocyte antigen stimulation assay are indicated. Obtain cerebrospinal fluid for Lyme antibody tests and polymerase chain reaction analysis to evaluate for Borrelia burgdorferi DNA.

A prospective, case-control study by Sohn et al of patients with acute-onset vertigo indicated that serum S100 binding protein β (S100β) and neuron-specific enolase (NSE) may aid in the differentiation of central vertigo from peripheral vertigo. The investigators found that serum levels of these brain-specific proteins were significantly higher in patients with central vertigo than in those with the peripheral condition or controls. [36]


Imaging Studies

Imaging studies are indicated when the symptoms are suspected to result from ischemia. MRI and MR angiography are the most helpful studies in assessing posterior circulation disorders and acute infarction. Diffusion-weighted MRI is sensitive and specific for early detection and differentiation between vasogenic and cytotoxic edema in patients with acute neurologic deficits.


Other Tests

Electronystagmography (ENG) is the most used vestibular test. When combined with the patient’s history and examination, the results of the ENG can be used to support a diagnosis of a peripheral or central etiology. [3, 4] Nystagmus patterns may be spontaneous or may be elicited by a change in gaze, head position, or head shake. Patterns of central and peripheral nystagmus were discussed in the Clinical section. Abnormalities in smooth pursuit or saccades are typically central in origin.

See the image below.

Electrode montage for electronystagmography (ENG) Electrode montage for electronystagmography (ENG) testing.

Formal evaluation with vestibular testing is indicated if the diagnosis is not apparent after obtaining a history and performing a physical examination. Vestibular testing can facilitate distinction between central, peripheral, and mixed causes of imbalance and vertigo. The test battery assesses labyrinthine function with caloric testing, rotational chair testing, and vestibular evoked myogenic potential. Oculomotor integrity is evaluated with eye tracking during smooth pursuit, saccades, and optokinetic stimulation. [6] The evaluation of spontaneous and gaze-evoked nystagmus can provide critical clues to central pathology.

Abnormalities found by oculomotor testing that suggest a central balance problem include saccade inaccuracy and smooth pursuit dysmetria. Failure to suppress nystagmus with visual fixation is often a sign of disease that affects the cerebellar flocculus or neural connections between the flocculus and the vestibular nuclei.

Positional testing with infrared oculography can be used to reveal nystagmus and to clearly define nystagmus patterns. Multidirectional nystagmus, spontaneous nystagmus, or positional nystagmus that is downbeat, torsional, or dissociated suggests a central lesion.

If symptoms suggest hypoperfusion, embolic events, or arrhythmia as the cause, perform a complete cardiac and peripheral vascular examination, including ECG, Holter monitoring, echocardiography, and carotid and vertebral Doppler ultrasonography.

A prospective study by Gerlier et al indicated that as used by trained emergency physicians, the HINTS (Head Impulse-Nystagmus-Test of Skew) and STANDING (SponTAneous Nystagmus, Direction, head Impulse test, standiNG) tests are better than the ABCD2 (age, blood pressure, clinical features, duration, diabetes) test for identifying central causes of vertigo in patients with isolated vertigo and unsteadiness. In terms of predicting central vertigo, the ABCD2 test failed in half such cases. [37]