Evoked potentials during active horizontal head rotations in patients with vertigo

Area of Science:

• Neuroscience
• Vestibular System Research
• Electroencephalography (EEG)

Background:

• Vertigo is a major symptom requiring accurate diagnosis.
• Differentiating causes of vertigo, including central and peripheral lesions, is clinically important.
• Evoked potentials offer a potential tool for neurophysiological assessment.

Purpose of the Study:

• To determine if evoked potentials from active head rotation can verify and differentiate vertigo patients.
• To identify specific electrophysiological markers associated with different vertigo etiologies.
• To assess the utility of evoked potentials in localizing brain lesions causing vertigo.

Main Methods:

• Analysis of evoked potentials in 24 healthy subjects and 43 patients with infratentorial or supratentorial brain lesions.
• Utilizing active horizontal head rotations as a stimulus.
• Identifying and analyzing specific peaks in the electroencephalogram (EEG) pattern, focusing on P155.

Main Results:

• Normal subjects exhibited a six-peak evoked response.
• The P155 component of the evoked potential was identified as the most stable and significant.
• P155 latency was found to be dependent on the trigger point and acceleration.
• P155 latencies were not significantly altered in peripheral vestibular disorders, cerebellar, or diffuse supratentorial lesions.
• Significant increases in P155 latency were observed in pontine lesions (homolaterally) and contralateral space-occupying tumors.

Conclusions:

• Active horizontal head rotations stimulate vestibulocortical pathways, providing a method for vertigo analysis.
• P155 latency changes in evoked potentials can help differentiate specific neurological lesions causing vertigo.
• This technique shows promise for improving the diagnostic accuracy of vertigo patients with central nervous system involvement.