Migraine-associated vertigo
Vestibular migraine (VM) is vertigo with migraine, either as a symptom of migraine or as a related neurological disorder. A 2010 report from the University of British Columbia published in the journal "Headache" said that Migraine associated vertigo' is emerging as a popular diagnosis for patients with recurrent vertigo" but, "in contrast to basilar artery migraine, is neither clinically nor biologically plausible as a migraine variant." Epidemiological studies indicate a strong link between vertigo and migraine. Signs and symptoms. Vertigo is a medically recognized term for the symptom of a vestibular system disturbance. It may include a  feeling of rotation or illusory sensations of motion or both. The general term dizziness is used by nonmedical people for those symptoms but often refers to a feeling of light-headedness, giddiness, drowsiness, or faintness, all of which must be differentiated from true vertigo, since the latter symptoms might have other causes. Motion sickness occurs more frequently in migraine patients (30–50% more than in controls). Benign paroxysmal vertigo of childhood is an example of migraine-associated vertigo in which headache does not often occur. Basilar artery migraine (BAM) consists of two or more symptoms (vertigo, tinnitus, decreased hearing, ataxia, dysarthria , visual symptoms in both hemifields or both eyes, diplopia, bilateral paresthesias, paresis, decreased consciousness and/or loss of consciousness) followed by throbbing headache. Auditory symptoms are rare. However, a study showed a fluctuating low-tone sensorineural hearing loss in more than 50% of patients with BAM with a noticeable change in hearing just before the onset of a migraine headache. The attacks of vertigo are usually concurrent with a headache and the family history is usually positive. The diagnostician must rule out: TIAs, and paroxysmal vestibular disorder accompanied by headache. There is also a familial vestibulopathy, familial benign recurrent vertigo (fBRV ), where episodes of vertigo occur with or without a migraine headache. Testing may show profound vestibular loss. The syndrome responds to acetazolamide. Familial hemiplegic migraine (FHM) has been linked to mutations in the calcium channel gene. (Ophoff et al. 1966 cf. Lempert et al.) Pathophysiology. The pathophysiology of MAV is not completely understood; both central and peripheral defects have been observed. Diagnosis. By the "Consensus document of the Barány Society and the International Headache Society" on the diagnostic criteria of vestibular migraine, the diagnostic criteria of vestibular migraine are: The diagnostic criteria of "probable vestibular migraine" are: Treatment. Treatment of  migraine-associated vertigo is the same as the treatment for migraine in general. There is not enough evidence to indicate which medications are most effective for preventing vestibular migraine. Epidemiology. The prevalence of migraine and vertigo is 1.6 times higher in 200 dizziness clinic patients than in 200 age- and sex-matched controls from an orthopaedic clinic. Among the patients with unclassified or idiopathic vertigo, the prevalence of migraine was shown to be elevated. In another study, migraine patients reported 2.5 times more vertigo and also 2.5 more dizzy spells during headache-free periods than the controls. MAV may occur  at any age with a female:male ratio of between 1.5 and 5:1. Familial occurrence is not uncommon. In most patients, migraine headaches begin earlier in life than MAV with years of headache-free periods before MAV manifests. In a diary study, the 1-month prevalence of MAV was 16%, frequency of MAV was higher and duration longer on days with headache, and MAV was a risk factor for co-morbid anxiety.