Diagnosis of vertebrobasilar insufficiency: time to rethink established dogma?

As isolated symptoms, vertigo, dizziness and imbalance are not regarded by neurologists as reflections of transient ischemia in the vertebrobasilar circulation. The purpose of this retrospective study was to demonstrate that these symptoms can and do occur in isolation. To this end, we analyzed the symptoms, stroke risk factors and diagnostic algorithms in 27 patients with a diagnosis of transient vertebrobasilar ischemia. None of the 27 patients included in the review complained of any associated neurologic symptoms. Against the reference standard of brain imaging, the site of the pathologic lesion was defined in the brainstem/cerebellum with the Torok monothermal caloric test, with a sensitivity greater than 86%. Vestibular decruitment and hyperactive caloric responses were of particular diagnostic value. Thus, we recommend that the neurologic dogma with regard to brainstem cerebellar ischemia be rethought.