RESUMO
Lateral medullary syndrome is one of the most well known and best characterized vascular syndromes of the vertebrobasilar circulation. This syndrome is most often caused by unilateral occlusive disease of the ipsilateral vertebral artery or its posterior inferior cerebellar artery branch. Bilateral lateral medullary syndromes are rare and the prognosis of this condition is grave. A 70-year-old hypertensive, diabetic woman developed sudden dizziness and gait ataxia. On neurologic examination, she had dysarthria, hoarseness, nystagmus, absent gag reflex, sensory changes on the right hemibody, and left limb and gait ataxia. Brain MRI revealed left middle and inferior lateral medullar infarction. Brain MR angiography revealed occlusion of the right vertebral artery and mild stenosis at the origin of the left vertebral artery with distal occlusion. Seven months later, she developed right lateral medullary syndrome. Repeated brain MRI revealed right upper lateral medullar and cerebellar infarction. We report a case of bilateral lateral medullary syndromes due to two consecutive medullary infarcts.