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Systematic approach needed to establish cause of vertigo.

Vertigo can be defined as an illusion or hallucination of movement. The control of balance is complicated. Vertigo can be caused by many different pathologies, some of which are potentially life threatening. An important differentiation is whether the symptoms of vertigo originate from a central or peripheral origin. Clues to a central origin are other brainstem symptoms or signs of acute onset such as headache, deafness and other neurological findings. These patients warrant urgent referral and investigation. Red flags in patients with vertigo include: headache; neurological symptoms; and neurological signs. It is useful to categorise vertigo into acute and chronic. The former usually has a single mechanism whereas chronic dizziness is often multifactorial. History is usually the most important part of the assessment. Key questions should be asked and it is vital to establish if the patient is suffering from vertigo or some other complaint such as anxiety or syncope. A neurological and otological examination should be performed, appropriate to the history. Assessment of gait and posture is crucial. If the patient has positional vertigo then a Hallpike test should be performed. Visual acuity should be checked as vision is a vital part of the balance system. The cranial nerves should be tested in particular eye movements for any ophthalmoplegia pointing to focal cranial nerve pathology and for nystagmus. The rest of the neurological examination should exclude evidence of central disease, in particular cerebellar disease, and neuropathy. If syncope is suspected it is wise to perform an extensive systemic examination in particular lying and standing BP, and cardiovascular and respiratory system assessments.