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- 2018
Peripheral Vestibular Evaluation - A New Horizon SciDoc Publishers | Open Access | Science Journals | Media PartnersDOI: http://dx.doi.org/10.19070/2572-732X-170002e Keywords: n/a Abstract: Vertigo, imbalance, and dizziness are reported with a 1-year prevalence in the adult population of 48.3%, 39.1%, and 35.6% respectively [1]. Falls in the elderly represent 2.8 million emergency departments visits each year [2]. Reportedly, 5-8% of children will experience vertigo in the general population [3-5]. These statistics exemplify a significant public health issue with significant implications across populations. There is universal agreement that any investigation for reported vertigo, imbalance, and dizziness begins with a thorough medical evaluation. Regardless of the patient population or presenting symptoms it is imperative to firstdetermine if any acute or chronic underlying medical conditions exist. This is, of course, not a simple task as the sheer number of possible pathologies resulting in vertigo, dizziness, and imbalance is daunting. Often, quantitative evaluations can be quite valuable in guiding medical management decisions. Peripheral vestibular evaluation specifically can provide quantitative information as part of the overall medical evaluation for patients reporting vertigo, dizziness, and/or imbalance. Electronystagmography (ENG), videonystagmography (VNG) and rotary chair testing (RCT) comprise a typical peripheral vestibular evaluation. Electrophysiologic measures such as auditory brainstem response (ABR) and electrocochleography (ECOG) may also be useful in the evaluation of select peripheral vestibular disorders. These protocols, in the absence of additional techniques, provide information about peripheral vestibular function and in many cases, prove effective and efficient. Of course, these techniques also have inherent challenges that can limit their overall effectiveness across a wide range of populations in both the clinic and in the scientific community. When assessing for peripheral vestibular hypofunction, either to confirm or rule out dysfunction, ENG/VNG and RCT only assess the horizontal semicircular canals (SCCs) and the superior division of vestibular nerve of the VIII cranial nerve. Additionally, caloric irrigation is an evaluation of non-physiologic low-frequency stimulation of the horizontal SCCs with RCT representing lowto mid-frequency stimulation. Neither caloric irrigation or RCT provide high-frequency stimulation. ABR evaluations can be quite valid for use in assessing patients for acoustic neuroma/ vestibular schwannoma (AN/VS), however imaging studies can also confirm AN/VS and it is exceedingly rare, reported to occur with 19 tumors per million per annually [6]. ECOG testing, used specifically in
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