The most important differentiating facts are peripheral vertigo presents with predominant vestibulocochlear signs and symptoms of vertigo, tinnitus and/or hearing impairment whereas central vertigo is often associated with other brainstem signs and symptoms. Occlusion can occur as a result of atherothrombosis or an embolism (e.g., cardioembolism or plaque from the vertebral arteries). Occlusion of the system, therefore, can result in either central or peripheral vertigo, depending on the specific artery affected. The vertebrobasilar arterial (VBA) system supplies blood to the brainstem, cerebellum, and peripheral labyrinths. Very often, the central oculomotor neuro-integrators (medial vestibular nucleus and the nucleus prepositus hypoglossi) are involved resulting in impairment of visual fixation and the clinical sign of nystagmus. The diagnosis is often made when other causes of vertigo were ruled out.Īny lesion affecting the central vestibular apparatus will present with vertigo as the main presenting symptom. Neuroimaging studies are generally normal. These patients usually present with recurrent vertigo lasting for a few hours without any other ENT symptoms nor focal neurological signs or symptoms. It is probably more commonly diagnosed in ENT practice versus internal medicine practice. Vertigo as a presentation of migraine is not uncommon, yet the actual incidence is unknown due to differences among physicians in their diagnosis. Migraine occurs in 12% of the adult population (6% men and 18% women). Multiple sclerosis, on the other hand, affects three times as many women as men.Īdditional causes of vertigo include multiple sclerosis, which has an incidence of approximately 10 to 80 cases per 100,000 individuals in the United States per year. Central vertigo is the most predominant symptom. Men tend to experience cerebrovascular disease more frequently than women, at a rate of about 2:1. The most common posterior circulation stroke is lateral medullary syndrome (Wallenberg), which arises as a result of occlusion of the posterior inferior cerebellar artery or more commonly the vertebral artery. Among all ischemic infarctions, 20% affected the posterior circulation. In the United States, approximately 800,000 individuals per year experience a stroke. The maintenance of visual fixation also requires the normal function of the oculomotor central neural integrator which consists mainly of the medial vestibular nucleus and the nucleus prepositus hypoglossi.Īny lesion affecting the vestibular nuclei or their projections especially those to and from the cerebellum will result in symptoms of vertigo and associated signs of nystagmus. maintaining visual fixation through the vestibulo-ocular reflex with changing head and body positions in space and extended or erect body posture. With these neuroanatomic arrangements, it will be easy to understand the functions of the vestibular system i.e. The vestibular nucleus on each side is divided into 4 sub-nuclei with three lateral nuclei and one medial nuclear column, they are labeled as the superior vestibular nucleus, lateral vestibular nucleus, medial vestibular nucleus, and descending vestibular nucleus. Some nuclei receive only primary vestibular afferents, but most receive afferents from the cerebellum, reticular formation, spinal cord, and contralateral vestibular nuclei. The projections from the vestibular nuclei extend to the cerebellum, extraocular nuclei, and spinal cord. The neuroepithelial hair cells within the peripheral vestibular apparatus send projections to the vestibular nuclei in the caudal pons and rostral dorsolateral medulla by way of the vestibular division of the VIIIth cranial (vestibulocochlear nerve). The peripheral vestibular system consists of the saccule, utricle, and semicircular canals. This is different from the light-headed "dizziness" which is more commonly secondary to global impairment of cerebral perfusion. The patient complains typically of dizziness with hallucination or sense of spinning. Central vertigo is a clinical condition in which an individual experiences hallucinations of motion of their surroundings, or a sensation of spinning, while remaining still, as a result of dysfunction of the vestibular structures in the central nervous system (CNS).
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