الفهرس 
Review of LiteratureOnly 14 pages are availabe for public view
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Abstract
7. SUMMARY
The vestibular system is broadly categorized into both peripheral and central components. The peripheral system is bilaterally composed of three semicircular canals (superior, posterior and lateral) and the otolithic organs (saccule and utricle). The semicircular canals detect rotational head movement while the utricle and saccule respond to linear acceleration and gravity respectively. These vestibular organs are in a state of symmetrically tonic activity that when excited stimulate the central vestibular system. This information along with proprioceptive and ocular input is processed by the central vestibular pathways (e.g. vestibular nuclei) and maintains our sense of balance and position.
Falling and loss of balance among the geriatric population is a frequent and serious problem. The reason has been attributed to the progressive deterioration of the anatomical components of the vestibular system.
Peripheral vestibular disorders are the most common cause of vertigo where they include pathology of inner ear vestibular structures as well as the vestibular portion of the eighth cranial nerve. Such pathology diminishes available sensory information regarding head position and movement. These disorders include vestibular neuritis, labyrinthitis, bilateral vestibular loss, Meniere’s disease, benign paroxysmal positional vertigo, vestibular schwannoma, superior canal dehiscence syndrome and vestibulopathy following surgical procedures (e.g. labyrinthectomy and acoustic neuroma).
The diagnosis of the peripheral vestibular disorders depends on history-taking, physical examination and investigations. Specific investigations for peripheral vestibular disorders are multiple including positional and positioning tests, caloric testing and rotatory chair testing recorded by electronystagmography or more recently videonystagmography.
These tests are essential but they only inform the clinician about one of the five pairs of labyrinthic receptors and they fail to establish a full picture of the functionality of the otolith receptors. VEMP testing has become a well established approach for the exploration of the sacculocollic pathways. This test has several advantages compared with other otolithic tests as it studies saccular function and the sacculocollic pathways selectively and never compensates.
VEMP is an otolith-mediated short-latency electromyographic response evoked by intense acoustic stimuli. They are measured in the ipsilateral tonically contracted sternocleidomastoid muscle. The VEMP response is thought to arise from the vestibulocollic (also called sacculocollic) reflex.
We did this study to evaluate the role of VEMP in peripheral vestibular disorders and whether it is a suitable test for differentiation between different types of peripheral vestibular disorders.
The study includes published medical articles concerning the role of VEMP in peripheral vestibular disorders. The search will be limited to articles published in English language on pubmed.
Our study analyzed (24) articles selected from (578) articles and abstracts according to the previously selected inclusion criteria.
Our results in this meta-analysis study as demonstrated in previously mentioned plotting of estimates showed that there is a statistical significance of VEMP test and it is an accurate test for differentiation between patients with peripheral vestibular disorders and healthy subjects and the VEMP test was able to differentiate between patients with peripheral vestibular disorders in subgroups and healthy subjects where the diagnostic accuracy was different according to the disease tested as the test more accurate in superior canal dehiscence syndrome, acoustic neuroma, vestibular neuritis, Meniere’s disease and benign paroxysmal positional vertigo respectively but the VEMP test is unable to differentiate between different types of peripheral vestibular disorders according to the nature of the disease. The results yielded by the search and analyzed by the meta-analysis software.