Inclusion Criteria:  patients with vertigo of central origin, syncopal attacks, frequent imbalance that not related to aural origin. clinical examination and imaging (MRI or CT) with the diagnosis standard of vertebrobasilar insufficiency including vertebrobasilar stroke and vertebrobasilar TIA. patients with abnormal lipogram and cervical spondylosis patients aged > 45 years old of both sex.  Exclusion Criteria:  subjective complain of aural vertigo or test to exclude aural vertigo. patients with malignant tumor. pregnant or lactating women. cognitive impairment and mental illness.